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Acs0507 Surgical Treatment Of Morbid Obesity 2008
- 1. © 2008 BC Decker Inc ACS Surgery: Principles and Practice
5 GI TRACT AND ABDOMEN 7 SURGICAL TREATMENT OF MORBID OBESITY — 1
7 SURGICAL TREATMENT OF
MORBID OBESITY
Eric J. DeMaria, MD, FACS, and Christopher J. Myers, MD
It is clear that severe obesity is associated with a significant anastomotic leakage). The ensuing discussion begins by
increase in morbidity1 and a decreased life expectancy.2 focusing on issues that the surgeon should carefully consider
Morbid obesity—defined as (a) a body weight that exceeds when operating on an extremely overweight patient.
the ideal body weight by 100 lb or more or (b) a body mass
index (BMI) greater than 35 kg/m2—has been shown to have
a significant genetic basis.3,4 To date, attempts to manage Much has been written about the increased health risks
morbid obesity with medical weight reduction programs have inherent in central (android) fat deposition as compared with
met with an unacceptably high incidence of recidivism.5 The peripheral (gynoid) fat deposition. It is thought that in the
approach that has had the greatest and longest-lasting success former, the increased metabolic activity of mesenteric fat
is associated with increased metabolism of amino acids to
in achieving weight loss is bariatric surgery.
sugar, which leads to hyperglycemia and hyperinsulinism.
Hyperinsulinism gives rise to increased sodium absorption
Preoperative Evaluation and hypertension. Furthermore, central obesity has been
linked to hypercholesterolemia. Hence, these patients have
Many surgeons are afraid to operate on the morbidly
a significantly higher incidence of diabetes, hypertension,
obese patient because they presuppose a marked increase in hypercholesterolemia, and gallstones8—which explains the
perioperative morbidity and mortality. It is now possible, higher mortality of the apple distribution of body fat in com-
however, to stratify the mortality risk for patients undergoing parison with the pear distribution. In the past, fat distribution
gastric bypass (GBP) by using a scoring system known as the was measured on the basis of the waist-to-hip ratio; however,
Obesity Surgery Mortality Risk Score (OS-MRS), which computed tomographic scanning has shown that abdominal
includes five independent variables that can be identified pre- circumference is a more accurate measurement of central fat
operatively: (1) BMI greater than or equal to 50 kg/m2, (2) distribution.9 Morbidly obese women have significantly
male gender, (3) hypertension, (4) pulmonary embolus risk increased intra-abdominal pressure (IAP), and this increase
(including previous thrombosis, pulmonary embolus, inferior is associated with stress and urge overflow urinary inconti-
vena cava [IVC] filter, right-side heart failure, and obesity nence.10 With weight loss comes a significant decrease in
hypoventilation syndrome [OHS]), and (5) patient age greater bladder pressure and correction of incontinence. IAP, as
than or equal to 45 years. These factors were associated with reflected in bladder pressure, appears to be closely correlated
a greater 90-day mortality in a prospective study of 2,075 with sagittal abdominal diameter and waist circumference but
patients who underwent GBP at a single institution,6 which not with waist-to-hip ratio (many morbidly obese patients
was the basis for the initial proposal of this scoring system. have both central and peripheral obesity). The increased IAP
The OS-MRS was subsequently validated in a multicenter associated with central obesity may give rise to other comorbid
study involving four institutions and 4,431 patients.7 With the factors as well, including venous stasis ulcers, OHS [see
Respiratory Insufficiency of Obesity, below], gastroesophageal
presence of each variable equal to 1 point, each patient’s
reflux, and inguinal and incisional hernias.
potential score ranged from 0 to 5. Patients with a score of 0
or 1 had a low mortality risk (group A; mortality, 0.2%); those
with a score of 2 or 3 had an intermediate mortality risk (group
Obese patients are at risk for respiratory difficulties, which
B; mortality, 1.1%); and those with a score of 4 or 5 had a
may be present before operation or may be exacerbated by an
high mortality risk (group C; mortality, 2.4%). These findings operation. The term pickwickian syndrome (which derives
suggest that the OS-MRS is a valuable tool that can be from The Posthumous Papers of the Pickwick Club, by Charles
effectively used to stratify risk and facilitate surgical decision Dickens) was resurrected from the late 1800s to describe a
making and patient discussion regarding bariatric surgery. morbidly obese 52-year-old man who fell asleep in a poker
Although the morbidly obese patient is certainly at greater game while holding a hand containing a full house.11 He was
risk, this risk can be markedly reduced by paying careful taken to the hospital by friends who presumed he was ill.
attention to detail in preoperative and postoperative care. The The pickwickian syndrome is now known to comprise two
increased risks encountered in these patients include wound pulmonary syndromes associated with morbid obesity: SAS
infection, dehiscence, thrombophlebitis, pulmonary embolism and OHS.12
(PE), anesthetic calamities, acute postoperative asphyxia in
patients with obstructive sleep apnea syndrome (SAS), acute Sleep Apnea Syndrome
respiratory failure, right ventricular or biventricular cardiac SAS is a potentially fatal complication of morbid obesity.
failure, and missed acute catastrophes of the abdomen (e.g., A diagnosis of SAS should be suspected when there is a
DOI 10.2310/7800.2008.S05C07
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5 GI TRACT AND ABDOMEN 7 SURGICAL TREATMENT OF MORBID OBESITY — 2
history of loud snoring, frequent nocturnal awakening with or have additional pulmonary problems, such as asthma,
shortness of breath, and daytime somnolence. It is estimated sarcoidosis, idiopathic pulmonary fibrosis, or recurrent PE.
that 2% of middle-aged women and 4% of middle-aged men One study of patients who underwent operation for morbid
in the US workforce have SAS, and the incidence is markedly obesity showed no statistically significant difference in weight
higher in the severely obese.13 Patients will often admit to between those who had OHS and those who did not.12
falling asleep while driving and waking up with their car on Chronic, severe hypoxemia is associated with three com-
the road’s median strip or bumping its guardrail. It is plications that put patients with OHS at risk: polycythemia,
extremely important that trauma surgeons be aware of the pulmonary arterial vasoconstriction, and pulmonary hyper-
relation between obesity and somnolence should a morbidly tension. The polycythemia further increases the already signifi-
obese patient be seen in the emergency department after an cant risk of venous thrombosis and PE. If the hemoglobin
automobile accident in which he or she fell asleep at the (Hb) concentration is 16 g/dl or greater, phlebotomy to a
wheel. Patients with SAS suffer from repeated attacks of concentration of 15 g/dl should be performed to reduce the
upper airway obstruction during sleep. The cause is probably postoperative risk of venous thrombosis. If the pulmonary
related to a large, fat tongue, as well as to excessive fat depo- arterial pressure (PAP) is 40 mm Hg or higher, consideration
sition in the uvula, pharynx, and hypopharynx. The normal should be given to prophylactic insertion of an IVC filter
genioglossus reflex is depressed, but this depression may be because of the high risk of a fatal pulmonary embolism in
secondary to the excessive weight of the tongue. These these patients.16 Placement of an IVC filter can be a challenge
patients are notorious snorers. As a result of inadequate stage because the appropriate landmarks cannot be identified in
IV and rapid eye movement (REM) sleep, they are markedly the operating room with fluoroscopy. It is necessary, before
somnolent during the day. operation, to tape a quarter to the patient’s back over the
Patients with SAS are at high risk for acute upper airway second lumbar vertebra with the aid of fixed radiographs
obstruction and respiratory arrest when undergoing an opera- and then, during operation, to aim for the quarter with the
tion and general anesthesia. Therefore, any patients with sus- insertion catheter, using fluoroscopy. Because these patients
pected SAS should undergo preoperative polysomnography are usually too heavy for angiography tables, the filter
at a sleep center to confirm the diagnosis. Medications are usually cannot be inserted percutaneously in the radiology
usually ineffective. Stimulants, such as methylphenidate department.
hydrochloride (Ritalin), should not be used. If a patient has Chronic hypoxemia also leads to pulmonary arterial vaso-
a respiratory disturbance index (RDI) greater than 25— constriction and severe pulmonary hypertension and eventu-
indicating more than 25 apneic or hypopneic episodes per ally to right-side heart failure or cor pulmonale with neck
hour of sleep—or has cardiac dysrhythmias in association vein distention, tricuspid valvular insufficiency, right upper
with apnea, treatment by nocturnal nasal continuous positive quadrant tenderness secondary to acute hepatic engorge-
airway pressure (nasal CPAP) should be provided. With ment, and massive peripheral edema.17,18 Such patients may
this technique, air flowing through a nasal mask against a also have a significantly elevated pulmonary artery wedge
constant airway resistance enters the nasal pharynx and pressure (PAWP), which suggests left ventricular dysfunc-
pushes the tongue forward to prevent recurrent obstruction.14 tion.17 Morbidly obese patients with a history of pulmonary
The pressure can be adjusted for each patient. Unfortunately, disease or a BMI greater than 50 kg/m2 should have pre-
many patients cannot tolerate the device, because it is cum- operative determinations of blood gas values. If arterial
bersome and noisy and tends to dry out the upper airway, blood gas (ABG) measurement reveals severe hypoxemia
though dryness can be prevented with an inexpensive room (i.e., arterial oxygen tension [PaO2] f55 mm Hg), severe
humidifier. If the patient has severe SAS with an RDI greater hypercapnia (arterial carbon dioxide tension [PaCO2] g47
than 40 and does not respond with elimination of the apneic mm Hg), or both, the patient should undergo Swan-Ganz
episodes or cannot tolerate nasal CPAP, a tracheostomy catheterization. If the PAWP is 18 mm Hg or greater, intra-
should be considered. An extra-long tracheostomy tube is venous furosemide should be administered for diuresis before
usually necessary because of the depth of the trachea in the elective operation. However, some patients may require a
morbidly obese patient. high ventricular filling pressure. A low cardiac output and
hypotension may follow diuresis, necessitating volume
Obesity Hypoventilation Syndrome reexpansion.
OHS is a condition associated with morbid obesity in which It is highly probable that some of the elevated PAP and
a person suffers from hypoxemia and hypercapnia when PAWP measurements are caused by the increased IAP in the
breathing room air while awake but resting.15 Spirometry morbidly obese patient [see Figure 2]).19,20 The high IAP leads
reveals decreases in forced vital capacity, residual lung to an elevated diaphragm, which in turn increases intrapleural
volume, expiratory reserve volume, functional residual capa- pressure and thereby PAP and PAWP; if the pleural pressure
city, and maximum minute volume ventilation, usually with- is measured with an esophageal transducer, the transmyocar-
out obstruction of airflow [see Figure 1]. The most profound dial pressure can be estimated. For this reason, these patients
decrease is that in expiratory reserve volume; it is probably may require a markedly elevated PAWP to maintain an
secondary to increased IAP and a high-riding diaphragm. adequate cardiac output, and excessive diuresis may lead to
Thus, these patients have a restrictive rather than an obstruc- hypotension. The same reasoning may be applied to a patient
tive pulmonary disease. The decreased expiratory reserve with a distended abdomen resulting from peritonitis and pan-
volume implies that many alveolar units are collapsed at end- creatitis in whom what seem to be unusually high cardiac
expiration, which leads to perfusion of unventilated alveoli, filling pressures are necessary. Therefore, one must rely
or shunting. Patients with OHS often are heavy smokers on relative changes in cardiac output in response to either
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5 GI TRACT AND ABDOMEN 7 SURGICAL TREATMENT OF MORBID OBESITY — 3
100 Figure 1 Impaired
pulmonary function
in the morbidly
* * obese improved
*
* * significantly
80
after weight loss
(% of predicted Value)
Pulmonary Function
* induced by gastric
operation.12
60 ERV = expiratory
reserve volume;
FEV1 = forced
expiratory volume
in one second; FRC
40
= functional
residual capacity;
FVC = forced vital
capacity; MVV =
20 maximal voluntary
ventilation; TLC =
FVC FEV1 MVV ERV FRC TLC total lung capacity.
Before Operation After Weight Loss
*p < .01 Compared with Preoperative Values
volume challenge or diuresis to determine the optimal PAWP open upper abdominal operations, when patients experience
in morbidly obese patients. a decrease in incisional pain.21
Patients with OHS respond rapidly to supplemental oxygen. It is important to emphasize that morbidly obese patients,
However, oxygen administration is occasionally associated especially those with respiratory insufficiency, should be
with significant CO2 retention, which necessitates intubation placed in the reverse Trendelenburg position to maximize
and mechanical ventilation. Because their pulmonary disease diaphragmatic excursion and to increase residual lung
is restrictive rather than obstructive, these patients are usually volume.22 These patients will often complain of air hunger
easy to ventilate without high peak airway pressures. ABG and respiratory distress when they lie supine. So-called break-
measurements need not return to normal values before ing of the bed at the waist may exacerbate the problem
extubation; it is only necessary that they return to their by pushing the abdominal contents into the chest, thereby
preoperative values. These values are achieved early after raising the diaphragm and further reducing lung volumes.
laparoscopic procedures and, on average, 4 days after major Placing these patients in the leg-down position may predis-
pose them to venous stasis, phlebitis, and PE; this tendency
should be offset with intermittent venous compression boots
[see Thrombophlebitis, Venous Stasis Ulcers, and Pulmonary
4.5 35
Embolism, below].23
Both SAS and OHS can be completely corrected with
Wedge Pressure (mm Hg)
Cardiac Index (L/min/m2)
weight reduction after gastric operation for morbid obesity:
3.5
* 25 the nocturnal apneas resolve, the PaO2 rises, and the PaCO2
* falls to normal as lung volumes improve.12
*
2.5 15 Morbidly obese patients are at significant risk for coronary
* * artery disease as a result of an increased incidence of systemic
hypertension, hypercholesterolemia, and diabetes. Because
RESUS of this increased risk for cardiac dysfunction, preoperative
1.5 5
electrocardiography should be performed on all obese patients
0 5 10 15 20 25 30 30 years of age or older.
Abdominal Pressure (mm Hg above Baseline)
Cardiac dysfunction in the morbidly obese patient is
Cardiac Index Wedge Pressure usually associated with respiratory insufficiency of obesity,
*p < .05 versus Baseline especially OHS.11 An elevated PAP in these patients may
be secondary to hypoxemia-induced pulmonary arterial vaso-
Figure 2 In a porcine model, raising intra-abdominal
pressure (IAP) caused cardiac index to fall and pulmonary constriction, to elevated left atrial pressures secondary to left
artery wedge pressure (PAWP) to rise. At an IAP of 25 mm ventricular dysfunction, or to a combination of these; it may
Hg, saline was given to restore intravascular volume; cardiac also be secondary to the increased pleural pressures arising
index returned to baseline levels, but PAWP remained from an elevated diaphragm secondary to increased IAP.17,20,23
elevated.20 It is unusual for morbidly obese patients without respiratory
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5 GI TRACT AND ABDOMEN 7 SURGICAL TREATMENT OF MORBID OBESITY — 4
insufficiency to experience significant cardiac dysfunction in and at appropriate intervals thereafter (depending on the
the absence of severe coronary artery disease. Morbidly obese type of heparin used) for at least 2 days or until the patient
patients often have systemic hypertension, which can aggra- is ambulatory. Because respiratory function in the morbidly
vate left ventricular dysfunction; however, mild left ventricu- obese patient is greatly enhanced with the reverse Trendelen-
lar dysfunction can be documented in many morbidly obese burg position, intermittent sequential venous compression
patients in the absence of systemic hypertension.24,25 Circulat- boots should be used to counteract the increased venous
ing blood volume, plasma volume, and cardiac output increase stasis and the propensity for clotting. It is important that
in proportion to body weight.25 Massively obese patients may the intermittent venous compression boots be used before
occasionally present with acute heart failure: it is reasonable induction of anesthesia and throughout the operative proce-
to assume that the enormous metabolic requirements of such dure. Such boots are usually part of a standard preoperative
patients can present a greater demand for blood flow than protocol in gastric procedures for weight control; their use
the heart can provide. Vigorous diuresis often corrects such should not be unintentionally neglected in preparation for
acute heart failure. Significant weight loss corrects pulmonary other elective or emergency procedures on morbidly obese
hypertension [see Figure 3], as well as the left ventricular patients. Patients with severe venous stasis disease (e.g.,
dysfunction associated with respiratory insufficiency.17,26 pretibial stasis ulcers or bronze edema) are at significantly
increased risk for fatal PE.29 Prophylactic insertion of an IVC
, , filter should be considered in these patients (as for patients
with OHS and a high PAP). All patients should make every
Morbidly obese individuals have difficulty walking, tend to attempt to walk during the evening after operation. Bariatric
be sedentary, have a large amount of abdominal weight rest- surgery–induced weight loss will correct the venous stasis
ing on their IVC, and have increased intrapleural pressure disease in most cases.29
(which impedes venous return).18,20 All of these conditions Venous stasis ulcers can be quite difficult to treat in a thin
increase the tendency toward phlebothrombosis. Patients are person; they are almost impossible to cure in a patient with
most at risk when immobilized in the supine position for long morbid obesity [see Figure 4]. The most important goal in
periods in the OR. These patients have been shown to have the management of these ulcers is weight loss, which almost
low levels of antithrombin, which may increase their tendency invariably leads to healing of the ulcer, probably as a result of
toward venous thrombosis.27 It has also been suggested that decreased IAP.29
starvation, particularly in the postoperative period, may be
associated with high levels of free fatty acids, which may pre-
dispose to perioperative thrombotic complications.28 Patients Approximately one third of morbidly obese patients either
with severe OHS often have a noticeably elevated PAP, which have had a cholecystectomy or may have had gallstones noted
can lead to right-side heart failure and can increase the risk at the time of another intra-abdominal operative procedure
of venous stasis and thrombosis. Investigators have noted that (e.g., a gastric operation for morbid obesity). Preoperative
patients with primary idiopathic pulmonary hypertension are evaluation of the gallbladder may be technically quite difficult
at significant risk for fatal PE.13 in morbidly obese patients because ultrasonography may
The risk of deep vein thrombosis (DVT) increases with fail to visualize gallstones. Intraoperative ultrasonography
a prolonged operation or a postoperative period of immobili- is probably much more accurate. Should symptomatic gall-
zation, and it increases even further in the morbidly obese stones be present in a patient undergoing a gastric procedure
patient. Standard or low-molecular-weight heparin should be for obesity, the gallbladder should be removed if the surgeon
administered subcutaneously 30 minutes before operation judges it safe to perform this additional procedure. If
80
Pulmonary Arterial Pressure (mm Hg)
70
60
50
40
30
20
10
0
Before 3–9 Months
Operation after Operation
Figure 3 Mean pulmonary arterial pressure was signifi- Figure 4 This chronic venous stasis ulcer was present for
cantly improved in 18 patients 3 to 9 months after gastric several years in a morbidly obese patient. Healing followed
surgery–induced weight loss of 42% P19% of excess weight. weight loss induced by a gastric operation.
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5 GI TRACT AND ABDOMEN 7 SURGICAL TREATMENT OF MORBID OBESITY — 5
placement of an adjustable gastric band is contemplated, the and sodium pentobarbital induction. One person elevates the
cholecystectomy should be undertaken first and the indwell- jaw, hyperextends the neck, and ensures a tight fit of the
ing device placed only in the absence of intra-abdominal bile mask, using both hands. To ensure adequate oxygen delivery,
spillage during the procedure. a second person compresses the ventilation reservoir bag,
In past studies, rapid weight loss led to the development using two hands because of the resistance to air flow from
of gallstones in 25 to 40% of patients who underwent GBP. the poorly compliant, heavy chest wall. After ventilation with
The risk of cholelithiasis in this setting can be reduced to 100% oxygen for several minutes, intubation is attempted.
2% by administering ursodeoxycholic acid, 300 mg orally If difficulties are encountered within 30 seconds, the steps
twice daily.30 Laparoscopic cholecsytectomy at the time of above should be repeated until the patient has been suc-
laparoscopic gastric bypass can be technically challenging; cessfully intubated. A volume ventilator is required during
consequently, many surgeons prefer to take an expectant operation. Placing the patient in the reverse Trendelenburg
approach to the gallbladder rather than complicate the bar- position expands total lung volume and facilitates ventila-
iatric procedure with a simultaneous cholecystectomy (unless tion22; however, the reverse Trendelenburg position increases
cholecystectomy is clearly indicated in a particular patient). lower-extremity venous pressure and therefore mandates the
use of intermittent sequential venous compression boots. It is
helpful to monitor blood gases through a radial arterial line
Pseudotumor cerebri is an unusual complication of morbid or a digital pulse oximeter.
obesity that is associated with benign intracranial hyperten-
sion, papilledema, blurred vision, headache, and elevated
cerebrospinal fluid pressures.31 It has been our experience
that patients with pseudotumor cerebri are not at any addi- Bariatric surgical procedures, like most other general surgi-
tional perioperative risk and that CSF need not be removed cal procedures, have undergone a transition from an open
before anesthesia and major abdominal operations. There is approach to one that places more emphasis on minimally
some theoretical concern that gastrointestinal contamination invasive or laparoscopic techniques. Laparoscopic GBP was
during GBP may cause shunt infection in patients who have first described in 1994 and became widely accepted in 1999,
been previously treated with indwelling shunts to relieve though it was not until 2004 that, according to a national
elevated CSF pressures. Successful weight reduction cures audit of bariatric surgery performed at academic centers, the
pseudotumor cerebri.32,33 number of laparoscopic GBP procedures performed exceeded
the number of open GBP procedures.
At present, the laparoscopic approach to GBP is favored
Degenerative osteoarthritis of the knees, hips, and back is because it achieves a comparable degree of weight loss
a common complication of morbid obesity. Weight reduction while possessing some notable advantages over its open coun-
alone may greatly reduce the pain and immobility that afflict terpart.21 Open GBP is performed through an upper midline
these patients. In some cases, the damage may be so extensive incision, whereas laparoscopic GBP is performed through five
that a total joint replacement is desirable; however, joint or six small incisions. Abdominal wall retractors and mechan-
replacement in patients who weigh more than 250 lb is ical retraction of the abdominal viscera, which are necessary
associated with an unacceptable incidence of loosening.34 for adequate exposure during an open procedure, are not
Weight reduction by means of a gastric bariatric operation required during a laparoscopic procedure, which makes use
may be the most sensible initial approach, to be followed by of gas insufflation (for pneumoperitoneum) and the effects
joint replacement after weight loss if pain and dysfunction of body positioning and gravity to facilitate intraoperative
persist. exposure. With the elimination of the large surgical incision
and mechanical retraction, the laparoscopic GBP patient
experiences less operative trauma, less postoperative pain,
Operative Planning and fewer wound-related complications. In addition, laparo-
scopic GBP yields less impairment of immediate postopera-
tive pulmonary function and a lower systemic stress response.
A 2007 study of 22,422 patients who underwent Roux-en-Y
Morbidly obese patients can be intimidating to the anes- GBP for treatment of morbid obesity compared the outcomes
thesiologist because they are at significant risk for com- of laparoscopic procedures (n=16,357) with those of open
plications from anesthesia, especially during induction. The procedures (n=6,065).35 The mean length of hospital stay
risk is particularly great for obese patients with respiratory was significantly lower in the laparoscopic group (2.7 days
insufficiency. An obese patient often has a short, fat neck and versus 4.0 days), as were the overall complication rate (7.4%
a heavy chest wall, which make intubation and ventilation versus 13.0%), the 30-day readmission rate (2.6% versus
a challenge. If endotracheal intubation proves difficult, 4.7%), the in-hospital mortality (0.1% versus 0.3%), and the
however, such a patient can usually be well ventilated with a mean cost ($13,743 versus $14,585 [US]).
mask. Awake intubation can be performed, with or without
fiberoptic aids, but is quite unpleasant and rarely necessary.
It is extremely important that at least two anesthesia The gastric operations performed for morbid obesity
personnel be present during induction and intubation for include both GBP procedures and gastric restrictive proce-
patients with respiratory insufficiency of obesity. An oral dures (i.e., gastroplasty and gastric banding). Randomized,
airway is inserted after muscle paralysis with succinylcholine prospective trials have conclusively shown that GBP is as
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5 GI TRACT AND ABDOMEN 7 SURGICAL TREATMENT OF MORBID OBESITY — 6
effective for weight control as the malabsorptive jejunoileal has been associated with a high incidence of deficiencies of
(JI) bypass is, while resulting in significantly fewer complica- fat-soluble vitamins, hypocalcemia-induced osteoporosis, and
tions.36,37 JI bypass is associated with a substantial incidence protein-calorie malnutrition.50 These nutritional deficiencies
of both early complications (e.g., acute cirrhosis, electrolyte may be more common in the United States, where fat intake
imbalance, and fulminant diarrhea)38 and late complications is high, than in many other countries. In Italy, for example,
(e.g., cirrhosis, interstitial nephritis, arthritis, enteritis, neph- starch intake (as in pasta) probably outstrips fat intake; still,
rocalcinosis, and recurrent oxalate renal stones).39 If evidence a number of Italian patients have had to be readmitted for
of cirrhosis, renal failure secondary to interstitial nephritis, or parenteral nutrition and extension of the common absorptive
other complications mandates reversal of a JI bypass, the intestinal tract because of refractory malnutrition. In some
patient, if not extremely ill, should be converted to a GBP; patients, it might be possible to convert a failed proximal
otherwise, all the lost weight is sure to be regained, and the GBP into a modified BPD with a 150 cm absorptive
obesity-related comorbidity will return. Admittedly, however, ileal limb (a procedure often referred to as distal GBP); how-
some patients have done well after JI bypass and do not need ever, these patients must also be monitored carefully for
to have the operation reversed. deficiencies of fat-soluble vitamins, for osteoporosis, and for
Several randomized, prospective trials have found that hor- malnutrition.
izontal gastroplasty yields poorer results than GBP.40-42 Fail- Superobese patients—defined as those whose weight is
ure of horizontal gastroplasty has generally been attributed to 225% of ideal body weight or greater or whose body mass
technical causes (e.g., enlargement of the proximal pouch or
index (BMI) is 50 kg/m2 or higher—will lose, on average,
the stoma or disruption of the staple line). Vertical banded
only about half of their excess weight, rather than two-thirds,
gastroplasty (VBG) was developed in the hope that it would
after standard GBP. In these patients, a 150 cm proximal
solve these technical problems and yield weight loss compa-
Roux-en-Y procedure (so-called long-limb GBP [see Open
rable to that seen after GBP without incurring the significant
Proximal Gastric Bypass, Operative Technique, below])
risk of iron, calcium, and vitamin B12 deficiencies associated
may increase weight loss in the first few years after operation
with GBP. In the 1990s, a procedure known as adjustable
without causing an increase in nutritional complications.51
silicone gastric banding was developed, which involved
placement of a restrictive ring around the proximal stomach In choosing the appropriate surgical approach, it is impor-
to create a small gastric pouch. In this restrictive procedure, tant to take into account the tremendous surgical revolution
which can be done laparoscopically in the vast majority that laparoscopy has brought about in the treatment of morbid
of patients, weight loss can be enhanced and vomiting obesity. Now that every operation performed to treat obesity
minimized by adjusting the ring diameter via transcutaneous can be done laparoscopically, laparoscopic bariatric surgery
access to the subcutaneous reservoir. is not only common but, in many centers, predominant.
Although VBG and, presumably, other restrictive proce- For this reason, as well as because laparoscopic obesity treat-
dures appear to be excellent from a technical point of view,43 ment requires advanced technical skills, minimally invasive
multiple randomized, prospective trials have found such bariatric procedures have become a cornerstone of training
approaches to be significantly less effective than standard for surgeons now learning laparoscopic surgery.
GBP. In one comparison trial, patients addicted to sweets
lost much more weight after GBP than after VBG because
Vertical Banded Gastroplasty
they experienced symptoms of dumping syndrome when
ingesting sweets.44 The failure rate was high after VBG
because these patients experienced no difficulties when eating
The first step in VBG is to make a circular stapled opening
candy or drinking nondietetic sodas. Subsequent random-
in the stomach 5 cm from the esophagogastric junction. A
ized, prospective trials confirmed the superiority of GBP.45,46
90 mm bariatric stapler with four parallel rows of staples is
Furthermore, maintenance of successful weight loss after
then applied once between this opening and the angle of His.
GBP appears to continue for as long as 14 years after opera-
(At this point, according to Mason, the originator of the
tion: in the average patient, weight loss amounts to about
two-thirds of excess weight at 1 to 3 years after operation, procedure, the volume of the pouch should be measured by
three-fifths at 5 years, and more than half in years 5 through means of an Ewald tube placed by the anesthetist; ideally,
10.47,48 It has been suggested that standard (i.e., proximal) pouch volume should be 15 ml.)
GBP will fail in 10 to 15% of patients because these patients Next, a strip of polypropylene mesh is wrapped around the
will frequently nibble on high-fat snacks (e.g., corn chips, gastrogastric outlet on the lesser curvature and sutured to
potato chips, and buttered popcorn). Such patients may have itself—but not to the stomach—in such a way as to create
to be converted to a combined restrictive and malabsorptive an outlet with a circumference of 5 cm for the small upper
procedure, such as partial biliopancreatic diversion (BPD).49 gastric pouch [see Figure 5a]. Some surgeons have used a
The original BPD procedure involves hemigastrectomy and stomal outlet 4.5 cm in circumference, but this smaller outlet
anastomosis of the distal 250 cm of intestine to the stomach; has not led to better weight loss; in fact, many patients
the bypassed small intestine is reanastomosed to the ileum with the 4.5 cm outlet exhibit maladaptive eating behavior,
50 cm from the ileocecal valve. BPD with duodenal switch is drinking high-calorie liquids because meat tends to get caught
a variant of the original procedure in which a linear gastric in the small stoma.
tube based on the lesser curvature is created (sleeve gastrec- Silastic ring gastroplasty [see Figure 5b] is a variant of VBG
tomy), with the pylorus left intact, and an ileal Roux limb is that uses a vertical staple line and a stoma reinforced with
brought up for anastomosis to the proximal duodenum. BPD Silastic tubing.
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a b
Figure 5 Vertical banded gastroplasty (VBG). Depicted are (a) standard VBG and (b) Silastic ring gastroplasty, a variant of
VBG in which the stoma is reinforced with a Silastic tube.
Laparoscopic Adjustable Gastric Banding
Complications of VBG include erosion of the polypro- Gastric banding is another form of gastroplasty, in which a
pylene mesh used to restrict the gastroplasty stoma into the synthetic band is placed around the stomach just below the
gastric lumen, enlargement of the pouch, stomal stenosis, esophagogastric junction. In several series, gastric banding
reflux esophagitis, and mild vitamin deficiencies.52 To date, has yielded markedly variable results with respect to achieve-
mesh erosion has been infrequently observed after VBG. ment of weight loss. Furthermore, it has been associated with
Pouch enlargement is fairly common with horizontal gastro- slipping or kinking of the banded stoma, obstruction at the
plasty but is much less likely to occur with VBG, in which the band, and intractable vomiting.
vertical staple line is placed in the thicker, more muscular Laparoscopic adjustable gastric banding (LAGB) is signifi-
part of the stomach. In addition, stomal diameter remains cant advance over open gastric banding procedures, primarily
fixed with the mesh band. If mesh erosion, pouch enlarge- because of the adjustability of the band. Open gastric banding
ment, stomal stenosis, disabling GI reflux, or recurrent procedures have used a variety of materials to constrict the
vomiting occurs, it is probably best to convert the patient to gastric lumen and carry a recognized risk of postoperative
GBP. In particular, patients with a Silastic ring VBG may nausea and vomiting that do not respond to any treatment
exhibit intractable vomiting of solid foods with no evidence short of reoperation. The adjustable gastric bands available
of mechanical obstruction. In our experience, conversion of for use in LAGB [see Figure 6] are silicone devices with an
these patients to GBP yields good results and eliminates inflatable reservoir that can be inflated or deflated postopera-
the vomiting problem. Finally, vitamin deficiencies can tively through a subcutaneous port placed deep in the abdom-
usually be prevented by having VBG patients take a standard inal wall for percutaneous access. Saline is injected into or
multivitamin daily for life. withdrawn from the reservoir to adjust gastric luminal diam-
eter. These diameter changes can be measured by means of
barium contrast evaluation, but currently, most adjustments
are made without x-ray guidance. If intractable vomiting
develops, saline can be removed from the band to alleviate
the problem; similarly, if the patient fails to lose weight after
operation, additional saline may be injected into the band to
narrow the gastric lumen further.
Use of the laparoscopically placed adjustable gastric band
(Lap-Band, Allergan Corp., Irvine, CA) was approved by the
US Food and Drug Administration in June 2001. Key data
on safety and effectiveness were provided by a prospective,
single-arm trial involving 299 patients at eight centers in the
United States. In this study, patients who completed 36
months of follow-up achieved a mean reduction in BMI of
Figure 6 Laparoscopic adjustable gastric banding. Shown is 39% and a mean overall loss of 18% of baseline body weight.
the adjustable gastric banding device used in the procedure. However, 28% of patients lost less than 10% of their initial
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body weight (a clear definition of failed weight loss). More
than half (62%) of these patients lost more than 25% of their
excess weight. Most patients (76%) experienced at least one
adverse event, and 33% of patients required removal of the
banding system.
Subsequent studies have yielded similar results. A 2007
review of two multicenter prospective, single-arm surgical
trials evaluating a total of 485 patients who underwent place-
ment of a gastric band (92% laparoscopically) between June
1995 and June 2001 suggested that the procedure was as
effective as was previously believed.53 The change in mean
BMI (kg/m2) was 38 to 47% at 1 year and 39% at 3 years.
The percentage of initial body weight lost was 17 to 18% at
1 year and 18% at 3 years. Similarly, most patients (66 to
76%) experienced upper GI symptoms at 1 year. In one of
the trials, 33% of the patients (96/292 patients) had had their
bands removed at 9 years, either because of complications or
because of inadequate weight loss.53
In a 2006 study comparing outcomes, LAGB proved to
be just as safe as, cheaper than, and almost as effective
as laparoscopic Roux-en-Y gastric bypass (LRYGB).54 This
retrospective review of 590 bariatric procedures (120 LRYGB,
470 LAGB) performed between November 2000 and July
2004 suggested that both operating time and duration of Figure 7 Laparoscopic adjustable gastric banding. Once in
hospitalization were significantly shorter in LAGB patients. the correct position on the proximal stomach, the adjustable
Complication rates and reoperation rates were similar in the band is locked into place.
two groups. Patients who underwent LRYGB initially lost
weight more rapidly: their mean percentage of excess body
weight lost (%EBWL) was 65% during postoperative year 1,
buckle—so as to hold the device in position. The band tubing
compared with 39% for LAGB patients. Thereafter, weight
is brought through the left midclavicular trocar port, which is
loss slowed, remaining nearly unchanged at 3 years (63%).
placed via the left midclavicular line subcostal trocar incision
Patients who underwent LAGB initially lost weight more
slowly, but the ongoing weight loss was continuous, eventu- and fixed to the abdominal wall fascia with sutures. The
ally approaching that of LRYGB. At 3 years, the %EBWL for tubing is connected to the reservoir, which is filled with
LAGB patients was 55%. saline.
LAGB is performed by using a five-port technique. Initial It is essential to place the band properly during the initial
abdominal access is obtained via a supraumbilical trocar, and procedure. The results to date suggest that the proximal
the remaining ports are placed sequentially along the right pouch must be very small to optimize weight loss. In
and left costal margins. The liver is retracted via the subxi- addition, proper placement minimizes—though it does not
phoid port, and the proximal stomach is visualized with a eliminate—the risk of band slippage and the complications
laparoscope inserted through the umbilical port. thereof.
Subsequent steps are done according to the pars flaccida Several techniques have been suggested for posterior
technique. A retrogastric tunnel for band insertion is created fixation of the band, but they are more difficult than anterior
at the posterior confluence of the diaphragmatic crura in a fixation techniques. With the pars flaccida technique,
plane of dissection that is easily developed with minimal posterior fixation of the band is not necessary to prevent band
blunt dissection after electrocauterization of the peritoneal slippage. Anterior fixation, however, is routinely performed,
membrane. This tunnel is placed cephalad to the posterior with interrupted sutures of nonabsorbable material placed
peritoneal reflection, so that the free space of the lesser sac between the distal and the proximal stomach to allow tissue
posterior to the stomach is not entered. Additional dissection to be apposed over the band and held in place.
is then carried out laterally at the angle of His to open the Although LAGB appears easier than many of the proce-
peritoneum and start clearing a plane behind the proximal dures done to treat obesity, there is a definite learning
stomach. curve. A number of surgical misadventures have been
A specially designed implement is inserted behind the reported, including gastric perforation, splenic injury, and
stomach from the lesser curvature to the angle of His and malpositioning of the band.
used to grasp the tubing of the banding device and pull it
around the stomach. The banding device is then locked
into place at the chosen location on the proximal stomach Band slippage (anterior, posterior, or concentric) may
[see Figure 7]. Gastrogastric sutures are placed to create a occur even after proper placement, resulting in intolerance of
tunnel of stomach overlying the banding device—but not the oral intake and vomiting. Such complaints are an indication
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for an upper GI series, which usually reveals dilatation of the
proximal pouch and rotation of the band [see Figure 8]. Initial How successful LAGB is at achieving weight loss over the
treatment consists of evacuating all saline from the band. long term remains unclear. The adjustability and reversibility
Frequently, however, the proximal pouch does not return of the operation, as well as the decreased disability that
to its normal size, and symptoms recur or fail to resolve. results, make it attractive to both patients and physicians.
Laparoscopic or open revision of the banding procedure is The procedure appears to avoid some of the major post-
then required; if the patient also has not lost a sufficient operative complications associated with open GBP (e.g.,
amount of weight, conversion to GBP may be recommended. incisional hernia, marginal ulcer, and stomal stenosis). Band
It is noteworthy that band erosion into the stomach, a not slippage remains a major postoperative concern, however,
infrequent complication of the use of mesh in VBG or in the though the incidence of slippage does appear to decrease as
Angelchik prosthesis for gastroesophageal reflux treatment, the surgeon’s experience with the procedure increases. More
has not been frequently reported. Longer follow-up is significant, there appears to be a high frequency of failed
necessary to evaluate the true extent of this risk. weight loss—as high as 15 to 20% of all patients undergoing
As after any form of gastroplasty, the patient may fail to the procedure and possibly even higher. European data
lose weight or may regain lost weight. Inappropriate eating confirm that there is a significant failure rate but also suggest
behaviors (e.g., intake of high-calorie sweets) are the most that the remaining patients achieve a degree of weight loss
likely cause. If obesity-related comorbid conditions persist, approaching that seen with proximal GBP. Whether these
conversion to proximal GBP is appropriate. reports will withstand the scrutiny of long-term follow-up
remains to be seen.
Open Proximal Gastric Bypass
a Proximal GBP results in greater weight loss than the gastric
restrictive procedures (see above) and carries a lower inci-
dence of weight regain; consequently, it is often considered
the gold standard for bariatric surgery. Compared with the
version of GBP performed at our institution, the original
GBP created a much larger proximal gastric pouch and a
much wider anastomotic opening, and it was often associated
with inadequate weight loss. In the later version, three super-
imposed 55 or 90 mm staple lines are placed across the prox-
imal stomach in such a way as to create a gastric pouch no
larger than 30 ml with a Roux limb at least 45 cm long and
a stoma no larger than 1 cm [see Figure 9]. This anatomic
situation is largely replicated when GBP is done laparoscopi-
cally, but an isolated gastric pouch is created with stapled
transection of the stomach.
b
Step 1: Initial Incision and Abdominal Exploration
Once the patient is anesthetized, the abdomen receives a
thorough, careful cleansing with povidone-iodine and is
draped in a sterile fashion. An upper midline incision is made
and extended through the fascia alongside the xiphoid pro-
cess to facilitate cephalad exposure. The incision is routinely
carried down to the supraumbilical area. The deep layer of
subcutaneous fat can often be separated bluntly with aggres-
sive lateral traction applied by the surgeon and the assistant,
and the midline usually can then be identified for fascial
incision. The electrocautery is used to enter the abdominal
cavity, and a thick layer of subfascial preperitoneal fat is
often encountered before entry into the peritoneal cavity.
Abdominal exploration is undertaken in every patient, includ-
ing examination of the liver for possible signs of liver disease.
Other incidental findings may become apparent as well.
Figure 8 Laparoscopic adjustable gastric banding. Contrast Troubleshooting Unexpected significant liver disease is
studies illustrate (a) a normally positioned laparoscopic occasionally discovered at the time of operation. If the patient
adjustable gastric band and (b) a slipped band. has cirrhosis without portal hypertension, one should perhaps
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Troubleshooting If dissection is too low laterally, it may
result in blunt injury to the short gastric vessels, bleeding, and
the need for urgent splenectomy, which is no easy task in a
morbidly obese patient. In addition, it may lead to creation
of an inappropriately large pouch by keeping the surgeon
from recognizing that some of the stomach is above the level
at which the encircling rubber drain is placed.
Step 3: Division of Mesentery and Dissection around Stomach
Once the esophagus is mobilized, the assistant’s left hand
is placed through the gastrohepatic omental opening behind
the stomach wall on the lesser curvature. The space between
the first and second branches of the left gastric artery is then
identified as a landmark for location of the gastric staple line,
both to ensure that the pouch created is no larger than 30 ml
and to prevent injury to the left gastric artery, which usually
runs cephalad to this location. With the surgeon’s posterior
finger pressing anteriorly to place tension on the tissue, a fine-
tip right-angle clamp and the electrocautery pencil are used
to divide the mesentery carefully at this level immediately
alongside the stomach wall so as to create a mesenteric
opening that will admit a large right-angle clamp.
The avascular tissue on the posterior wall of the stomach
is then bluntly dissected between the opening in the gastro-
hepatic omentum and the lateral angle of His, which is
identified by the encircling rubber drain. The blunt tip of a
Figure 9 Open proximal gastric bypass. Depicted is the large 28 French red rubber tube is placed behind the stomach
completed procedure. in a medial-to-lateral direction along this dissected path to
encircle the stomach [see Figure 10]. The open end of the red
proceed with bypass if the patient’s comorbid conditions rubber tube is subsequently brought through the previously
make it mandatory; liver transplantation carries increased created mesenteric opening with a large right-angle clamp.
risk in morbidly obese patients. The gallbladder should be The stomach is now ready for stapling, and the red rubber
palpated for gallstones, which, if found, may be an indication tube serves as a guide for introduction of the stapler. At this
for cholecystectomy at the time of the bypass procedure. If point, all intraluminal tubes and devices (e.g., the nasogastric
there are no visual or palpable gallbladder abnormalities, tube and the esophageal stethoscope) are removed from the
intraoperative ultrasonography may be used to examine the esophagus by the anesthetist.
gallbladder.
It is not unusual to discover other previously unrecognized Troubleshooting When a tube is inadvertently stapled
conditions during GBP, primarily because symptoms may within the stomach, excising it from the nontransected
not be obvious in morbidly obese patients and because their
large size tends to make radiologic imaging difficult or even
impossible. For example, intraoperative discovery of pelvic
cysts and tumors is not uncommon in obese female patients.
Such lesions may be excised during GBP; on occasion, if they
appear benign and their location prevents safe excision, they
may be managed with careful follow-up.
Step 2: Mobilization of Esophagus
The bypass procedure itself is begun by mobilizing the
distal esophagus and encircling it with a soft rubber drain
0.5 in. in diameter. The gastrohepatic omentum is bluntly
entered at a point overlying the caudate lobe, with care taken
to look for and avoid injury to an aberrant left hepatic artery.
The phrenoesophageal ligament overlying the anterior and
lateral distal esophagus is sharply incised to facilitate subse-
quent blunt mobilization of the distal esophagus. To prevent
esophageal injury, the nasogastric tube is carefully palpated
within the lumen of the esophagus during mobilization, Figure 10 Open proximal gastric bypass. After dissection of
and blunt dissection proceeds widely around this important the avascular tissue on the posterior gastric wall, a red rubber
landmark. Laterally, dissection must be at the level of the catheter is passed through the resulting space to encircle the
esophagus or higher. stomach.
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gastric staple line can be a technical challenge. To remove the
stapled tube, it is generally necessary to use a stapler to tran-
sect the stomach, thereby creating the potential for significant
injury to the gastric tissue unless the transection is precisely
superimposed over the previous staple line. The tube can
then be excised from each side (proximal and distal) of the
divided gastric staple lines.
Step 4: Creation and Mobilization of Roux Limb and
Jejunojejunostomy
The ligament of Treitz is identified, and the jejunum is
measured to a point 45 cm beyond the ligament—or some-
what more distally to enhance mobilization of what will
become the Roux limb if the mesentery appears foreshort-
ened—at which point the jejunum is divided with a stapler.
An 8 to 12 cm segment of jejunum may be resected at this
Figure 11 Open proximal gastric bypass. The stomach is
point to create a larger mesenteric defect, which should stapled to create the small proximal pouch. The stapler is
facilitate mobilization of the limb to the proximal stomach. fired three times to create three superimposed staple lines,
Mesenteric dissection is carried posteriorly in fat with the thereby decreasing the risk of staple line disruption.
sequential application of clamps until further dissection
appears either unnecessary for mobilization or unwise (i.e.,
likely to cause mesenteric vascular injury or ischemia of the
A 1 cm anastomosis is created between the proximal stom-
Roux limb).
ach pouch and the Roux limb. We prefer a handsewn anas-
A side-to-side jejunojejunostomy is then created with a
tomosis for this procedure, using an outer layer composed
60 mm linear stapler at least 45 cm beyond the initial point
of interrupted 2-0 or 3-0 silk sutures and an inner layer
of jejunal division for standard proximal GBP. Some sur-
composed of a continuous absorbable 3-0 polyglycolic acid
geons perform this anastomosis 150 cm downstream for the
(Dexon) suture. When the posterior aspect of the anastomo-
long-limb modification of the procedure used in superobese
sis is complete, a 30 French dilator is placed orally by the
patients [see Operative Planning, Choice of Surgical Proce-
anesthetist and is guided through the anastomosis by the sur-
dure, above] or even further distally for the distal GBP
geon to ensure that the stoma has the appropriate diameter
modification, which greatly enhances malabsorption. It is
[see Figure 12]. The anterior aspect of the anastomosis is then
important not to narrow the efferent lumen at the jejunoje-
completed.
junostomy site, particularly with the longer-limb modifica-
tions, in which the lumen at the distal end of the Roux limb
Troubleshooting A significant concern for many bariat-
may be quite small. The enterotomies made to allow place-
ric surgeons has been a high incidence of staple line disrup-
ment of the stapler can usually be closed with a 55 mm
tion causing failed weight loss or weight regain; in one series,
stapler loaded with 3.5 mm staples; however, if stapling
the incidence of such disruption was 35%. To minimize
would cause undue narrowing of the lumen, the closures
this risk, some surgeons advocate transecting the stomach.
should be handsewn instead.
Currently, this step is routinely carried out as part of a
Troubleshooting It may be preferable to mobilize the
Roux limb before committing to stapling the stomach so that
it can be determined whether the limb can be extended
to reach the proximal stomach without being placed under
tension. In those rare cases in which the mesentery is too
foreshortened to permit the limb to reach the proximal stom-
ach, it is advisable to change the procedure to VBG or gastric
banding rather than create a gastrojejunal anastomosis under
tension and thereby incur the increased risk of leakage.
Step 5: Gastric Stapling and Gastrojejunostomy
The Roux limb is brought through the mesentery of the
transverse colon with blunt dissection and then brought up to
the proximal stomach. The 55 or 90 mm stapler, loaded with
4.8 mm staples, is guided behind the stomach by inserting
its open-mouthed end into the lumen of the previously posi-
tioned red rubber tube. Once it is determined that the staple
line will reach completely across the stomach and that the Figure 12 Open proximal gastric bypass. When the posterior
stomach is not folded on itself, the stomach is stapled aspect of the gastrojejunal anastomosis has been completed, a
three times in such a way that the three staple lines are 30 French dilator is placed through the stoma to confirm that
superimposed [see Figure 11]. the opening is correctly sized.
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laparoscopic GBP. In an open GBP, one may transect the feeding if a fistula develops. Fortunately, such fistulas are
stomach either by applying a linear cutting stapler with 3.5 or rare. When they do occur, they often heal if (1) they are well
4.8 mm staples (depending on the estimated gastric wall drained, (2) there is no distal obstruction or local abscess,
thickness) or by inserting two parallel noncutting transverse and (3) the patient is receiving nutritional support with no
anastomosis (TA)–90 staplers and cutting between them with oral intake. A gastrostomy tube should also be placed in the
a scalpel after the staplers are fired. Other surgeons, however, distal gastric pouch when extensive adhesions from a previous
prefer to leave the stomach undivided and oversew the staple procedure or a difficult gastric reoperation increase the risk of
line. In our version of open GBP, we find that placing three postoperative gastric distention.
or four precisely superimposed staple lines reduces the
incidence of staple line disruption to less than 2%. Step 7: Closure
Another advantage of gastric transection besides reduction When the absence of leakage is confirmed or when any
of staple line disruption is that it allows the Roux limb to leaks identified have been controlled, the tip of the nasogas-
be brought up to the gastric pouch via a retrocolic and retro- tric tube may be positioned further down in the Roux limb
gastric tract, which is substantially shorter and places less and left to continuous suction overnight. All mesenteric
tension on the limb. This approach is particularly helpful defects—at the jejunojejunostomy, at the mesocolon, and
in severely obese patients with a fatty and foreshortened behind the Roux limb (Peterson hernia)—are then closed
mesentery, in whom it is difficult to free the Roux limb to prevent an internal hernia. The abdominal fascia is reap-
sufficiently to reach the proximal stomach without tension. proximated with a continuous double-looped No. 2 suture,
The possibility that gastric transection may prove helpful subcutaneous tissues are irrigated with a crystalloid solution,
in a specific patient is another reason why it is advisable to and the skin is closed with skin staples. No subcutaneous
delay stapling the stomach until the Roux limb has been sutures or drains are used in routine cases.
mobilized.
Step 6: Assessment of Anastomosis Proximal GBP is associated with a significant incidence
When the entire anastomosis is complete, the dilator is of stomal stenosis and with marginal ulcer.55 The former
removed and an 18 French nasogastric tube is advanced by responds to endoscopic stomal dilatation, and the latter
the anesthetist while the tip is carefully guided through the usually responds to proton pump inhibitor (PPI) therapy.
anastomosis by the surgeon. The Roux limb is occluded with Addition of sucralfate to this regimen may be helpful. The
the assistant’s left hand or with an atraumatic intestinal risk of marginal ulcer appears to be increased in smokers and
clamp, and the esophagus is occluded by placing tension on in patients who consume nonsteroidal anti-inflammatory
the rubber drain surrounding it while the anesthetist injects a drugs (NSAIDs). We routinely discourage NSAID use after
series of 10 ml aliquots of methylene blue dye through the GBP. Perforation of the proximal gastric pouch, probably
nasogastric tube to determine whether the anastomosis is arising from perforation of a deep ulcer, has been seen with
leaking. A total of 30 to 60 ml of methylene blue must usually administration of high-dose NSAIDs or with untreated ulcer
be injected; lesser amounts will not stress the suture line diathesis.
enough to constitute an adequate test. Alternatively, the Iron, vitamin B12, and folic acid deficiencies may occur
anastomosis can be tested by performing intraoperative but can usually be corrected with oral supplementation52;
gastroscopy. If leakage is present, the air insufflated during accordingly, GBP patients, like VBG and gastric banding
the procedure will be visible bubbling from the leaking patients, should be advised to take a multivitamin daily for
areas when the air-distended anastomosis is submerged in life. Compared with gastroplasty and gastric banding, GBP
irrigation fluid. results in significantly lower serum hemoglobin and iron
concentrations. This is primarily a problem in menstruating
Troubleshooting When an intraoperative leak is identi- women. All menstruating women who have undergone GBP
fied, the area of leakage should be oversewn with silk sutures should be treated prophylactically with supplemental oral
until injection of additional methylene blue dye via the naso- ferrous sulfate, 325 mg/day. As many as six iron tablets a day
gastric tube yields no further leakage. The most difficult area may be required if menstrual bleeding is heavy. Hormonal
to repair is the posterior suture line, which is quite close to therapy to control or temporarily eliminate menses may be
the gastric staple line. Posterior leaks are usually repaired by helpful. On occasion, intramuscular iron injections or, rarely,
reinforcing the posterior suture line with additional sutures hysterectomy may be necessary. The risk of vitamin B12
between the excluded stomach and the jejunal limb; often, deficiency is higher after GBP than after gastroplasty or
the entire posterior suture line is oversewn. In addition, a gastric banding, but this condition can be prevented with
viable pedicle of omentum may be mobilized and placed supplemental oral vitamin B12, 500 mg/day. A few patients
around the anastomosis for further reinforcement. Closed may require (or prefer) monthly B12 injections, which they
suction drains may also be placed in this area, both to detect can learn to administer themselves.
possible postoperative leakage and to control a postoperative Concerns have been expressed that GBP can lead to other
leak or fistula. divalent cation deficiencies. Our group has not encountered
Finally, a gastrostomy tube may be placed in the excluded zinc deficiencies 5 to 9 years after GBP, though we have
portion of the stomach. This measure provides postoperative observed calcium deficiencies leading to osteoporosis, which
decompression, which should prevent the development may take many years to become manifest and may not
of undue tension on the Roux limb as a result of gastric be biochemically evident because of normal serum calcium
distention. In addition, it establishes a route for enteral levels. It is therefore recommended that all GBP patients
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5 GI TRACT AND ABDOMEN 7 SURGICAL TREATMENT OF MORBID OBESITY — 13
take oral calcium supplements. Some may require vitamin D Laparoscopic Gastric Bypass
supplementation. Magnesium deficiencies should be treated Laparoscopic GBP is currently the most popular bariatric
with MgSO4 supplementation. procedure in the United States, both because of the rapid
Although nutritional deficiencies do not appear to be a
weight loss it achieves and because of the strong overall surgi-
greater problem with long-limb GBP than with standard
cal trend toward minimally invasive approaches. As noted [see
proximal GBP, monitoring patients for possible malabsorp-
Operative Planning, Laparoscopic versus Open Approach to
tion of the fat-soluble vitamins A, D, and E after long-limb
Bariatric Surgery, above], laparoscopic GBP achieves the
GBP is advisable.
same weight-loss results as open GBP but yields less pain,
BPD may be associated with all of the complications seen
reduced disability, and a shorter duration of hospitalization.
after GBP. In addition, patients who undergo BPD may
Physiologically, laparoscopic GBP results in less operative
experience diarrhea, severe protein malnutrition (manifested
trauma than open GBP, less impairment of pulmonary func-
as hypoalbuminemia), and deficiencies of vitamins A (mani-
tion, and a less pronounced stress response. In addition, the
fested as severe night blindness), D (manifested as severe
laparoscopic technique is associated with lower incidences of
osteoporosis), and E.50 Hypoalbuminemia may respond to
oral pancreatic enzymes but often must be treated with total major wound infections and incisional hernias. Accordingly,
parenteral nutrition. In some patients, it may prove necessary we recommend laparoscopic GBP over any other bariatric
to lengthen the absorptive intestinal tract from 50 cm to procedure.
200 cm. Laparoscopic GBP poses significant technical challenges,
even for surgeons with advanced laparoscopic skills. Most
of the variations seen at different institutions are related to
A series of 672 open proximal GBP procedures reported various techniques for creation of the gastrojejunal anastomo-
a 1.2% incidence of anastomotic leakage with peritonitis, sis, with some groups using a circular stapler, others a linear
a 4.4% incidence of severe wound infections (defined as stapler, and still others a handsewn technique. The anvil of
infections serious enough to delay hospital discharge), an the circular stapler may be placed within the proximal gastric
11.4% incidence of minor wound infections and seromas pouch either by means of flexible upper GI endoscopy,
(which were easily treated at home), a less than 1% incidence through an approach similar to the snare-and-wire technique
of gastric staple line disruption with the use of three superim- used for placement of a percutaneous endoscopic gastros-
posed applications of a 90 mm linear stapler, a 15% incidence tomy (PEG) tube [see 5:18 Gastrointestinal Endoscopy], or by
of stomal stenosis, a 13% incidence of marginal ulcer, a means of a gastrotomy of the stomach before pouch creation
16.9% incidence of incisional hernia, and a 10% incidence for intra-abdominal anvil placement, followed by staple
of cholecystitis necessitating cholecystectomy.47 Gallstones closure of the gastrotomy. Peroral placement of the stapler’s
developed in 32% of the GBP patients who had a normal anvil can be problematic: even the small 21 mm anvil is hard
intraoperative gallbladder sonogram within 6 months of to pass through the proximal esophagus in some patients.
surgery, and sludge was observed in another 10%. In a mul- To facilitate esophageal passage, a “flip-top” anvil design has
ticenter randomized, prospective trial, the incidence of been introduced. With this design, a 25 mm anvil can gener-
gallstones within 6 months of GBP was reduced from 32% to ally be passed without undue difficulty, thereby lowering the
2% by giving patients ursodeoxycholic acid, 300 mg twice risk of postoperative stenosis. We routinely use the linear
daily.56 Gallstone formation beyond 6 months is uncommon. stapling method to create the gastrojejunal anastomosis; it is
The operative mortality in this series was less than 1%. easier than circular stapling in this setting, and there is no risk
Patients with respiratory insufficiency of obesity had an oper- of esophageal trauma from anvil passage.
ative mortality of 2.2%, whereas those without pulmonary
dysfunction had an operative mortality of 0.4%.
Neither the data from this randomized, prospective trial
Step 1: Initial Access and Trocar Placement
nor the data from selective studies support the contention
that VBG is safer than GBP. Although GBP includes one Initial access to the abdomen is obtained through a small
more anastomosis than VBG, complications such as leaks and left subcostal incision. Gas is insufflated into the abdomen via
peritonitis occur with both operations. A common criticism a Veress needle to a pressure of 15 mm Hg; on occasion, a
of GBP is that it is difficult to evaluate the distal gastric pouch pressure of 18 to 20 mm Hg may be necessary. A dilating
and duodenum after the operation. Such evaluation, how- 5 mm trocar is then placed in this location. Many surgeons
ever, can be done in 75% of patients by means of retrograde use commercially available trocars that allow direct vision
passage of an endoscope into the duodenum and the stomach through the scope during passage of a 12 mm trocar. We
and in other patients by means of percutaneous distal disten- encourage preinsufflation of the abdominal cavity before such
tion gastrography. Bleeding from either the distal gastric a device is employed so as to enhance identification of the
pouch or a duodenal ulcer is rare. Gastric mucosal metaplasia peritoneal sac and avoid organ injury. Additional trocars
of the bypassed portion of the stomach may occur in some are placed in specific locations [see Figure 13]. The liver is
5% of patients after retrograde endoscopy, a finding that has retracted with a metal Nathanson liver retraction device
raised concerns regarding the risk of carcinoma arising at that anchored to the bed, which is inserted after a 5 mm sharp
location. To date, however, although many thousands of trocar is used to develop a tract into the abdominal cavity
these procedures have been performed over the past four in the subxiphoid position and removed. If the left lateral
decades, few cases of cancer in the bypassed stomach have section of the liver is very large (as in patients with steatosis),
been reported. additional liver retractors may be necessary.
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