Various surgical and anesthesiological risks

Various surgical and
anesthesiological risks
OSA,delirium,transfusion in orthop
surgery,difficult
spi,hypothermia,mental
illness,blindness,hypotension during
C/S

Frances Chung, Balaji Yegneswaran, Pu Liao, Sharon A. Chung,
Santhira Vairavanathan, Sazzadul Islam, Ali Khajehdehi, Colin M.
Shapiro, STOP Questionnaire.#A Tool to Screen Patients for
Obstructive Sleep Apnea .Anesthesiology 2008; 108:812–21
• Background: Obstructive sleep apnea (OSA) is a major risk factor for
perioperative adverse events. However, no screening tool for OSA has been
validated in surgical patients.
• This study was conducted to develop and validate a concise and easy-to-use
• questionnaire for OSA screening in surgical patients.
• Methods: After hospital ethics approval, preoperative patients aged 18 yr or
older and without previously diagnosed OSA were recruited. After a factor
analysis, reliability check, and pilot study; four yes/no questions were used to
develop this screening tool. The four questions were respectively related to
• snoring, tiredness during daytime, observed apnea, and high blood pressure
(STOP). For validation, the score from the STOP questionnaire was evaluated
versus the apnea–hypopnea index from monitored polysomnography.

Stop questionnaire .A Tool to Screen
Patients for Obstructive Sleep Apnea
• Results: The STOP questionnaire was given to 2,467 patients,
27.5% classified as being at high risk of OSA. Two hundred eleven
patients underwent polysomnography, 34 for the pilot test and
177 for validation. In the validation group, the apnea– hypopnea
index was 20 6. The sensitivities of the STOP questionnaire with
apnea–hypopnea index greater than 5, greater than 15, and
greater than 30 as cutoffs were 65.6, 74.3, and 79.5%,
respectively. When incorporating body mass index, age, neck
circumference, and gender into the STOP questionnaire,
sensitivities were increased to 83.6, 92.9, and 100% with the same
apnea–hypopnea index cutoffs.
• Conclusions: The STOP questionnaire is a concise and easyto- use
screening tool for OSA. It has been developed and validated in
surgical patients at preoperative clinics. Combined with body
mass index, age, neck size, and gender, it had a high sensitivity,
especially for patients with moderate to severe OSA.

STOP Questionnaire.A Tool to Screen Patients for
Obstructive Sleep Apnea .Anesthesiology 2008;
108:812–21
• OBSTRUCTIVE sleep apnea (OSA) is the most prevalent
breathing disturbance in sleep, affecting 2–26% of the
general population depending on sex, age, and the
definition of criteria.
• OSA is associated with significant morbidity, including
excessive daytime sleepiness, loud snoring during
sleep, refractory hypertension, and impaired quality of
life.
• Studies have also shown that OSA is associated with a
high risk for traffic accidents and cardiovascular
disease.

108:812–21
• It is estimated that nearly 80% of men and 93% of women
with moderate to severe sleep apnea are undiagnosed.
• Undiagnosed OSA may pose a variety of problems for
anesthesiologists. A number of case reports have
documented an increase in the incidence of postoperative
complications and deaths among patients suspected of
having OSA.
• Untreated OSA patients are known to have a higher
incidence of difficult intubation, postoperative
complications, increased intensive care unit admissions,
and greater duration of hospital stay.
• Identifying patients with OSA is the first step in preventing
postoperative complications due to OSA

S.T.O.P.:snore,tired,observed(stopped
breathing),pressure
• (STOP Q1–4)
• related to snoring, tiredness during the daytime,
stopped breathing during sleep, and hypertension
were designed.
• S—“Do you snore loudly (louder than talking or loud
enough to be heard through closed doors)?”
• T—“Do you often feel tired, fatigued, or sleepy during
daytime?”
• O—“Has anyone observed you stop breathing during
your sleep?
• ” P—“Do you have or are you being treated for high
blood pressure?

Stop tradotto:quasi corrisponde
• S—“Do you snore loudly (louder than talking or loud enough to be
heard through closed doors)?”Russi forte,+ che parlare a voce alta
tanto da essere udito a porta chiusa?Sornacchiare
• T—“Do you often feel tired, fatigued, or sleepy during daytime?”ti
senti stanco,affaticato o sonnolento durante il giorno? Tirato……..
• O—“Has anyone observed you stop breathing during your sleep?
Nessuno ti ha osservato fermare il respiro durante il sonno?
osservato
• ” P—“Do you have or are you being treated for high blood pressure?
Hai o sei stato in terapia per ipertensione?Pressione

clinical diagnosis of OSA
• The clinical diagnosis of OSA was defined as
AHI(apnea /hypopnea) greater than 5
with fragmented sleep and daytime
sleepiness.
• According to the American Academy of Sleep
Medicine practice guideline, the severity of
OSA is determined by the AHI: 5–15, mild;
greater than 15–30, moderate; greater than
30, severe.

Stop Bang
• incorporating BMI, age, neck circumference,
and gender into the STOP scoring (STOP-
Bang), the sensitivity and NPV significantly
increased. They were both more than 90% for
the patients with moderate and severe OSA.

108:812–21
• Appendix 1: STOP Questionnaire
• Height _____ inches/cm Weight _____ lb/kg
• Age _____ Male/Female BMI _____
• Collar size of shirt: S, M, L, XL, or _____
inches/cm
• Neck circumference* _____ cm

Appendix 2: STOP-Bang Scoring
Model
• 1. Snoring Do you snore loudly (louder than talking or loud enough to be
heard through c losed doors)? Yes No
• 2. Tired Do you often feel tired, fatigued, or sleepy during daytime? Yes
No
• 3. Observed Has anyone observed you stop breathing during your sleep?
Yes No
• 4. Blood pressure Do you have or are you being treated for high blood
pressure? Yes No
• 5. BMI BMI more than 35 kg/m2? Yes No
• 6. Age Age over 50 yr old? Yes No
• 7. Neck circumference Neck circumference greater than 40 cm? Yes No
• 8. Gender Gender male? Yes No
• High risk of OSA: answering yes to three or more items
• Low risk of OSA: answering yes to less than three items

108:812–21• Studies have documented an increased incidence of coronary artery diseases,
hypertension, cerebrovascular accidents, gastroesophageal reflux disease,
congestive heart failure, and myocardial infarction in OSA patients.
• It is estimated that the average life span of an untreated OSA patient is 58 yr,
which is 20 yr shorter than the average life span of the general population
(men, 79 yr; women, 83 yr).
• OSA is also associated with an increased incidence of postoperative adverse
events. Undiagnosed OSA in surgical patients have a serious impact on the
postoperative outcome.
• Identifying patients with a high risk of OSA is the first step for the prevention
of adverse health events, adverse perioperative outcomes, and its treatment.
Screening tools work as a filter to separate the patients with a high risk of OSA
from the patients with a low risk of OSA. A good screening tool should be
validated in the target population against an accepted standard. It should be
easy to use and have a high sensitivity and acceptable specificity.

108:812–21
• Most screening tools for OSA so far have been validated in patients referred to sleep clinics or
sleep laboratories.
• Seven predictive models, based on the different combinations of witnessed apneas, snoring,
gasping, BMI, age, gender, and hypertension were developed and validated in the patients from
sleep centers.16,18,19,21,23,24,39,40
• The Sleep Disorders Questionnaire,41 Apnea Score,25 and Global Sleep Assessment Questionnaire
were all tested in patients mainly from sleep centers.42 Patients referred to sleep centers are
suspected of having sleep related disorders, especially OSA. They are preselected patients.
Screening tools for OSA developed and validated in the sleep center patient population cannot be
applied to other patient populations without validation in the target patient population.
• The Berlin questionnaire is one of the few questionnaires that have been validated in primary care
patients.30 However, instead of monitored polysomnography in a sleep laboratory, home portable
sleep monitoring was used for the validation of the Berlin questionnaire. Home portable sleep
monitoring has not been accepted as the standard for the diagnosis of OSA. The STOP
questionnaire is currently the only questionnaire developed and validated in surgical patients.
• Although there was some self-selection from the patients’ perspective, our study was designed to
include all surgical patients in our preoperative clinics regardless of their score of the STOP
questionnaire to avoid selection biases

Apolipoprotein E e4 Allele Increases
the Risk of Early
Postoperative Delirium in Older
Patients Undergoing
Noncardiac Surgery

Apolipoprotein E e4 Allele Increases the Risk of Early
Postoperative Delirium in Older Patients Undergoing
Noncardiac Surgery Leung, JM , Sands LP, Yun Wang , Poon A, Kwok P, Kane JP,
Pullinger CR. Anesthesiology 2007; 107:406–11
• Methods: The authors conducted a nested cohort study to include patients aged > 65 yr
who were scheduled to undergo major noncardiac surgery requiring
anesthesia. A structured interview was conducted preoperatively and for the first 2 days
postoperatively to determine the presence of delirium, defined using the Confusion
Assessment Method.
• Blood was drawn for measurement of the apolipoprotein genotypes. Bivariate tests of
association were conducted between delirium and apolipoprotein genotypes and other
potentially important risk factors.
• Variables that had significant bivariate association with postoperative delirium were entered in
a forward multivariable logistic regression model.
• Results: Of the 190 patients studied, 15.3% developed delirium on both days 1 and 2 after
surgery. Forty-six patients (24.2%) had at least one copy of the apolipoprotein e4 allele.
• The presence of one copy of the e4 allele was associated with an increased risk of early
postoperative delirium (28.3% vs. 11.1%; P 0.005). Even after adjusting for covariates, patients
with one copy of the e4 allele were still more likely to have an increased risk of early
postoperative delirium (odds ratio, 3.64; 95% confidence interval, 1.51–8.77) compared with
those without the e4 allele.
• Conclusions: Apolipoprotein e4 carrier status was associated with an increased risk for early
postoperative delirium after controlling for known demographic and clinical risk factors.
• These results suggest that genetic predisposition plays a role and may interact with
anesthetic/surgical factors contributing to the development of early postoperative delirium.

Importance of the E4 allele of the
apolipoprotein E(APOE) gene
• Genetic studies in population-based investigations2,3 have demonstrated a
relation between certain genotypes and the risk of dementia and cognitive
decline. Specifically, elevated risk of Alzheimer disease has been demonstrated
among individuals with the E4 allele of the apolipoprotein E(APOE) gene in many
populations.4,5 The E4 allele of APOE is associated with a shift to an earlier age at
onset of Alzheimer disease.6 However, the APOE E4 genotype is neither necessary
nor sufficient for the occurrence ofAlzheimer disease.6 The APOE polymorphism
also affects response to trauma, age-related cognitive decline,7 and several other
disorders.8–10
• APOE is a polymorphic protein associated with plasma lipoproteins.
Three major isoforms can be recognized, designated as APOE2, APOE3,
and APOE4, according to their relative position after isoelectric
focusing.11 APOE is unique among apolipoproteins in that it has a special
relevance to nervous tissue.12
• APOE is involved in the mobilization and redistribution of cholesterol in
repair,growth, and maintenance of myelin and neuronal membranes
during development or after injury.13–15 Whether patients who
subsequently develop postoperative delirium have a genetic predisposition that
renders them at risk for early postoperative delirium has not been determined.

• The covariates included:
• age,
• education,
• amount of alcohol intake
• History of central nervous system disorders,
• preoperative depressive symptoms,
• preoperative functional status
• pain levels.
• amount of alcohol intake (more than 2 drinks vs. 2 drinks or fewer per day)
• depression,
• functional status.
• Depression was measured using the Geriatric Depression Scale and defined as the presence of six or more symptoms
of depression.23
•
• Preoperative demographics included
• age,
• highest education level achieved,
• perioperative blood pressure measurements.
• Other perioperative data :
• type of surgery;
• the American Society of Anesthesiologists physical status,26 which incorporates
• the number and severity of preoperative comorbid conditions;
• the type of anesthesia (general, regional, or combined).
• Surgical risk was estimated using the guidelines from the American College of Cardiology and American Heart
Association update for the perioperative cardiovascular evaluation for noncardiac surgery, which takes into
consideration the type and duration ofsurgery, and intraoperative blood loss.2

patients who developed postoperative delirium that
persisted for 2 days after surgery
Apolipoprotein E e4 Allele Increases the Risk of Early Postoperative Delirium in Older Patients Undergoing
Noncardiac Surgery Leung, JM , Sands LP, Yun Wang , Poon A, Kwok P, Kane JP, Pullinger CR.
Anesthesiology 2007; 107:406–11
• were older
• Dependent in one or more independent activities of daily living
• Had a history of central nervous system disorder
• had lower systolic postoperative blood pressures on postoperative day 1
• had increased pain levels at rest on postoperative day 1
• Patients who had postoperative delirium that persisted for 2 days after
surgery had significantly longer hospital stay than those without delirium
(8.1 6.7 vs. 5.1 3.5 days; P 0.0008).
• Of the 190 patients studied, 46 (24.2%) had at least one copy of the e4 allele. The presence of
one copy of the e4 allele was associated with an increased risk of postoperative delirium that
persisted for 2 days after surgery (28.3% vs. 11.1%; P 0.005). Even after adjusting for covariates
associated with postoperative delirium, which included age, change in postoperative pain levels,
history of central nervous disorders, and so on, patients with at least one copy of the e4 allele
were still more likely to have an increased risk of postoperative delirium

Factors associated with postop delirium
Apolipoprotein E e4 Allele Increases the Risk of Early Postoperative Delirium in Older Patients
Undergoing Noncardiac Surgery Leung, JM , Sands LP, Yun Wang , Poon A, Kwok P, Kane JP, Pullinger
CR. Anesthesiology 2007; 107:406–11

• What is the possible mechanism between apolipoprotein and
postoperative delirium? Previous studies suggest that the
effects of APOE are mediated through alterations in lipid
transport in regenerating neurons,proinflammatory cytokine
release from activated microglia,amyloid precursor protein
metabolism, increasedblood brain carrier permeability,
alterations in plateletfunction, and systemic
inflammation.41,42,43 One hypothesized mechanism is
that APOE e4 allele diminishes the capacity for
repair in cases of cerebral injury or capacity for
homeostasis/maintenance.

Prevedibilità delle trasfusioni in
chirurgia protesica ortopedica
• Anesth Analg. 2004 Oct;99(4):1239-
44,Predicting allogeneic blood transfusion use
in total joint arthroplasty.Rashiq S, Shah M,
Chow AK, O'Connor PJ, Finegan BA.
• essa si basa su un semplice punteggio derivato
da età,sesso,peso,Hb,ASA,e se
revisione o no:

Anesth Analg. 2004 Oct;99(4):1239-44,Predicting allogeneic
blood transfusion use in total joint arthroplasty.Rashiq S,
Shah M, Chow AK, O'Connor PJ, Finegan BA
punteggio Rischio di trasfusione %
0-100 10 o meno
100-150 10-30
150-200 30-50
>200 >50

Equazione completa ricavata dalla tavola
Anesth Analg. 2004 Oct;99(4):1239-44,Predicting allogeneic blood transfusion use in total joint arthroplasty.
Rashiq S, Shah M, Chow AK, O'Connor PJ, Finegan BA

Anesth Analg. 2004 Oct;99(4):1239-44,Predicting allogeneic blood
transfusion use in total joint arthroplasty.Rashiq S, Shah M, Chow AK,
O'Connor PJ, Finegan BA
punteggio Rischio di trasfusione %
0-100 10 o meno
100-150 10-30
150-200 30-50
>200 >50

Predicibilità di anestesia spinale difficile
Br J Anaesth. 2004 Mar;92(3):354-60. Epub 2004 Jan 22.Development
of a difficulty score for spinal anaesthesia.Atallah MM, Demian AD,
Shorrab AA.

Prevedibilità dell’ipotermia in anestesia generale
Anesth Analg. 2002 Nov;95(5):1381-3, Preoperative risk factors of
intraoperative hypothermia in major surgery under general anesthesia.
Kasai T, Hirose M, Yaegashi K, Matsukawa T, Takamata A, Tanaka Y
• modello: Z = -15.014 + 0.097 x (Age) + 0.263 x
(Height) - 0.323 x (Weight) - 0.055 x
(Preoperative systolic blood pressure) - 0.121 x
(Preoperative heart rate).
• La probabilità di andare incontro ad ipotermia
può poi essere stimata secondo: = 1/(1 + e(-)(Z)).
• La core temp.infatti ha dimostrato un decremento significativo in pazienti con
P >0.7.Quindi aumenti di età e altezza e decrementi nella formula peso * PAS
e FC(peso,PAS e FC + bassi) sono in grado di fornire una discreta stima della
evenienza della ipotermia intraop. durantre chirurgia maggiore.

Il rischio perioperatorio nei malati mentali
Ann Surg. 2008 Jul;248(1):31-8.Postoperative complications in the seriously mentally ill: a systematic review of the literature.
Copeland LA, Zeber JE, Pugh MJ, Mortensen EM, Restrepo MI, Lawrence VA
• Da quel poco che è stato pubblicato la schizofrenia emerge come
fattore di rischio per mortalità e morbilità,quest’ultima
peculiare per frequenza di ileo paralitico postop e confusione mentale.
• questi pazienti sembrerebbero resistenti al dolore .
• Pazienti affetti da disordini depressivi seri presentano una
elevata incidenza di delirio postop e di confusione
mentale.
• Da notare che tali complicanze sono più frequenti quando si
sospendono le terapie abituali nel periodo preop.
– Ann Surg. 2008 Jul;248(1):31-8.Postoperative complications in the seriously mentally ill: a systematic review of the literature.
Copeland LA, Zeber JE, Pugh MJ, Mortensen EM, Restrepo MI, Lawrence VA

Il rischio di perdita della vista
• Durante chirurgia oftalmica:
• 3% di tutte le controversie legali raccolte dall’ASa Closed claim
• Gild W,Posner K,Kaplan R,Cheney F. Eye Injuries Associated with Anesthesia A Closed
Claims Analysis. Anesthesiology. 76(2):204-208, February 1992.
• danno corneale(35%),raramente (16%) definitivo
• Danno globale dell’occhio(30%),derivante dal movimento
improvviso del paziente durante anestesia o sedazione e con
esito invariabile in perdita delle visione.
• durante altre chirurgie
• Perioperative Visual Loss After Nonocular surgery.Amer.J.Ophtalmology 2008,145:604-
10.Newmann J.
• 0.002 - 0.2% di tutte le procedure
• Rischio aumentato in : chirurgia cardiaca, chir colonna vertebrale e del
collo e per posizione prona.L’eziologia è sconosciuta,ma è attribuita a
ischemia del nervo ottico,da ipotensione,vasocostrizione,aumento della pressione
venosa,ipossia,oltre a fattori anatomici e fisiologici locali propri del paziente.

Prevedibilità della ipotensione da
spinale nel cesareo
• Int J Obstet Anesth. 2007 Apr;16(2):128-34. Prediction of hypotension during spinal
anesthesia for Cesarean section and its relation to the effect of crystalloid or colloid
preload.Dahlgren G, Granath F, Wessel H, Irestedt L.
• supine stress test with measurement of maternal heart rate, blood pressure,
right uterine artery pulsatility index and symptoms in the left lateral and
supine positions.
• stress test was positive in 36%
• The sensitivity and specificity of the stress test for clinically significant hypotension
(symptomatic hypotension) for patients randomized to the crystalloid group (n=25)
were 69 and 92% respectively.
• Patients with a positive stress test receiving a crystalloid preload showed a higher
frequency of hypotension compared to all other groups, 90% vs. 33%, (P=0.003) and
also a greater need for ephedrine, mean dose (SD): 20.0 (9.7) vs. 8.4 (9.0) mg (P=0.002).
• CONCLUSIONS: Pregnant women with a positive preoperative supine stress test
constitute a subset at increased risk for clinically significant hypotension during
cesarean delivery under spinal anesthesia. These women seem more likely to benefit
from prophylactic colloid solution than women with a negative stress test.

Heart rate variability predicts severe
hypotension after spinal anesthesia
• Heart rate variability predicts severe hypotension after spinal anesthesia. Anesthesiology.
2006 Mar;104(3):537-45
• Hanss R, Bein B, Weseloh H, Bauer M, Cavus E, Steinfath M, Scholz J, Tonner PH.
• low to high frequency ratio (LF/HF) before SA.
• Sensitivity and specificity of LF/HF for prediction of decrease of SBP greater 20% of baseline
were tested.
• Retrospective analysis showed differences of LF/HF depending on the degree of hypotension
after SA.
• Prospective analysis demonstrated significant differences of SBP after SA depending on
baseline LF/HF (mean +/- SD): low LF/HF (1.3 +/- 0.7) = > SBP: 91 +/- 8% of baseline versus
high LF/HF (5.5 +/- 2.4) = > SBP: 66 +/- 10% of baseline (P < 0.05). Baseline LF/HF as
well as high frequency and proportional decrease of SBP
after SA correlated significantly, A receiver operator curve characteristic
analysis showed a sensitivity and specificity of LF/HF > 2.5 of 85% to predict SBP decrease of
greater than 20% of baseline after SA. CONCLUSIONS: Heart rate variability analysis before
SA may predict hypotension after SA with high sensitivity and specificity. LF/HF may be a tool
to detect patients at high risk of hypotension due to SA. This indicates that the predictive
value of LF/HF is superior to established predictors.

Heart rate variability predicts severe hypotension after spinal
anesthesia. Anesthesiology. 2006 Mar;104(3):537-45
Hanss R, Bein B, Weseloh H, Bauer M, Cavus E, Steinfath M,
Scholz J, Tonner PH.
• Heart rate variability analysis was performed according to the Task Force recommendations.13 Five-
minute recordings of the fast peaks of R waves on the electrocardiogram were detected with a sample
rate of 1,024 Hz (TF4; Varia Cardio, Olomouc, Czech Republic). The beat to- beat
variability of consecutive R waves of the sinus rhythm was measured. Data were
investigated based on time as well as frequency domain analysis. For time domain
analysis, the mean interval of consecutive beat to- beat intervals and the SD of mean beat-to-beat
intervals were investigated, both known to reflect parasympathetic activity.14,15 Frequency domain
analysis was based on fast Fourier transformation. Power spectrum densities were calculated for low
frequencies (LF: 0.04– 0.15 Hz) and high frequencies (HF: 0.15– 0.4 Hz) in normalized units, defined as the
LF or HF proportional part of the total power. Breathing was controlled at a rate of 14–16 breaths/min as
recommended for HRV measurements.16

• Patients demonstrated significant differences of SBP
after SA depending on LF/HF at DOS-BL (fig. 1B). SBP
of LF/HF 2.5 patients decreased to 91 8% of
baseline,whereas SBP of LF/HF 2.5 patients
decreased significantly to 66 10% of baseline (P 0.05
vs.baseline; P 0.05 vs. LF/HF 2.5). LF/HF 2.5
patients required no vasopressor intervention,
whereas in LF/HF 2.5 patients, a mean of 1.0 0.1 ml
was administered to restore blood pressure (P 0.05).

1. Hemodynamic data. Decrease of systolic blood pressure (SBP) demonstrated as proportional
decrease from baseline (BL). (A) SBP, retrospective groups. (B) SBP, prospective groups. DOS-PRE day of
surgery after prehydration; LF/HF < 2.5 baseline low to high frequency ratio less than 2.5; LF/HF > 2.5
baseline low to high frequency ratio greater than 2.5; LOW lowest value after spinal anesthesia; MILD
mild hypotension; MOD moderate hypotension; SA5 5 min after spinal anesthesia; SA15 15 min
after spinal anesthesia; SEV severe hypotension. Data are presented as mean SD. * P < 0.05 MILD
versus MOD as well as SEV. P < 0.05 versus changes within group versus baseline. # P < 0.05 LF/HF < 2.5
versus LF/HF > 2.5.

Heart rate variability predicts severe hypotension after
spinal anesthesia. Anesthesiology. 2006 Mar;104(3):537-45
.Hanss R, Bein B, Weseloh H, Bauer M, Cavus E, Steinfath
M, Scholz J, Tonner PH.
• We conclude that LF/HF of 2.5 may be a cutoff value
independent from underlying individual conditions. To
evaluate its predictive value, preoperative LF/HF was
correlated with the degree of SBP decrease after SA. A
significant correlation was demonstrated, and a high
sensitivity and specificity of LF/HF 2.5 to predict
hypotension was shown. In addition, baseline HF
(reflecting vagal activity) was correlated with the
percentage decrease of SBP

Various surgical and anesthesiological risks

Empfohlen

Empfohlen

Weitere ähnliche Inhalte

Was ist angesagt?

Was ist angesagt? (19)

Andere mochten auch

Andere mochten auch (10)

Ähnlich wie Various surgical and anesthesiological risks

Ähnlich wie Various surgical and anesthesiological risks (20)

Mehr von Claudio Melloni

Mehr von Claudio Melloni (20)

Kürzlich hochgeladen

Kürzlich hochgeladen (20)

Various surgical and anesthesiological risks