1. NEONATAL SURGICAL
EMERGENCIES & ANAESTHETIC
MANAGEMENT
Dr.Narasimha Reddy, M.D.,DA
Professor & H.O.D,
Dept. of Anaesthesiology,
Kurnool Medical College ,
Kurnool

2. PART I
PHYSIOLOGICAL
CONSIDERATIONS
&
ANAESTHETIC
IMPLICATIONS

3. • Neonatal surgical emergencies are common
in developing countries.
– High birth rate
– Consanguinity
– Infections during pregnancy
– Multiple pregnancies
– malnutrition

4. Some terminologies:
• Fetus: intrauterine period
• Newborn: upto 12 hrs after birth
• Neonate: upto 30 days after birth
• Infant: first 12 months of age.
• Gestational age:time from conception to
birth
• Post-natal age:time from birth to present time
• Post-conceptual age:from conception to present
age (G.A+post natal age)

5. CNS
• Gets 1/3rd of CO
• Autoregulation present, but not effective
• Myelination incomplete, senses are active
• Can feel pain , can smell & hear
• Blood – brain barrier
– Immature,hydrophilic & lipophilic cross the barrier
– Autonomic regulation good
– Parasympathetic domination
– Less number of receptors & variant protein binding

6. CNS…..
• InterVentricular hemorrhage:
– Surgical stimulation,
– inadequate analgesia,
– Airway instrumentation,
– Excessive transfusion,
prematures are more prone,
stressed neonate lacks autoregulation,
Fluctuations in CPP

7. CVS
• Heart contractile mass 30%,
• Ventricles less compliant,
• CO 350- 400ml/kg/mt.
• CO depends on heart rate & SV
• O2 consumption is 7 ml/kg/mt.
• Bradycardia is due to hypoxia, low CO,
vagal stimulation in anesthesia

8. AUTONOMIC NERVOUS SYSTEM
• Baroreceptors are immature & sensitive to
anesthetics
• Sympathectomy due to spinal or epidural-
no fall in B.P.(as sympathetic system is
immature).
• Fall of BP & HR due to sympathetic
blockade is offset by inhibition or
withdrawal of cardiac vagal activity.

9. RESPIRATORY SYSTEM
• Neonate has a large head, small weak
neck,obligate nose breather, large tongue,
U-shaped epiglottis,
funnel shaped larynx,
Subglottic portion is the narrowest
larynx is anterior & cephalad
cricoid is complete ring,
tracheal length is 2-5 cms.

10. • Respiratory centre is immature & sensitive to
depressant drugs
• More in prematures, apnoeic episodes are
common
• Lung volumes
– Tidal volume is small, 6 ml/kg 15 ml/kg
– O2 consumption is 7-9 ml/kg
– Resp.rate & alveolar vent. 2-3 times adult.
– FRC/VA ratio in neonates is 0.23,
– Changes in FiO2 causes rapid changes in oxygenation,
– MV/FRC is 5:1
– Less number of underdeveloped alveoli, surfactant less
– Ventilation is better controlled in infants < 3/12 of age

11. BLOOD
• Hb 18-19 gm/dl.
• PCV 60%
• Fetal Hb 70-90%
• ODC shifted to left
• Blood volume 80 ml/kg
• Cardiac index ,i.e CO/BSA is more

12. KIDNEYS
1. Decreased renal blood flow& decreased GFR
Days 6-24 mths
Urine vol. 1.5 2.4
ml/kg/hr
Osmolality 40-900 50-1400
EC vol.(%B.W) 42 34
Body fluid vol./ 82-107 70-75
ml/kg
Higher BSA & immature skin-evaporative losses

13. Metabolism & Thermal
Homeostasis
• O2 consumption is 7 ml/kg/mt – 7th day
• Temperature control is the most imp.
Consideration in pediatric anesthesia
• Metabolism drives MV & CO by increasing rate.
• Resting energy requirements is double that of
older child.
• Glucose is primay substrate for heart & brain

14. Metabolism & Thermal Homeostasis……
• Neonate has core temp. of 370C
– Increasing metabolic demands,
– Decreased stored carbohydrates,
– Decreased liver function,
– Increasing tendency to hypoglycemia
– Heat production by non shivering mech.

15. Metabolism & Thermal Homeostasis…..
• Neutral thermal state: minimal O2 consumption
when the difference of core & skin temp.is <
2-40C.
• Hypothermia leads to-
– catecholamines- O2 consumption
– pulmonary & peripheral vasoconstriction
– metabolic acidosis, resp.depression
– depressed conscious state, delayed recovery
– prolonged action of drugs,reduced surfactant
– dysarrythmias & cardiac depression

16. Fluid & Electrolyte Balance
• Initial fluid replacement must be low
• Overhydration can cause pulmonary edema
• Neonate requires Na: 2-3 meq/kg/day
• K : 2-3meq/kg/day
• Hypocalcemia is common in premature, sick &
acidotic
• Daily maintenance of Ca 500mg/kg/day
• Hypoglycemia is common in prematures
< 20mgs/dl

17. PAC & OPTIMISATION
• Keep in mind
– Neonatal problems
– Surgical problems
– Associated congenital problems
• Maintain
– Clear airway
– O2 therapy to achieve PaO2 of 50-70mm.Hg
– Stomach decompression
– Keep the baby warm at 370 C.
– I.V.line
– Correct acidosis if pH is < 7.3 with soda bicarb.
1-2meq/kg, slow infusion over 10-30 mts.

18. PAC & OPTIMISATION…..
– Ventilate if PaCO2 is > 50mm.Hg.
– Correct dehydration ( crystalloids),
• Insensible loss
• GI losses
• Others
– Correct hypovolemia ( colloids)
• Albumin, plasma, RBC, & whole blood if
necessary.
– Arterial line in critically ill patients.

19. MONITORING
• Precordial stethoscope or esophageal steth.
• ECG lead II
• BP cuff, oscillometer, arterial cath
• CVP – int.jugular, cubital vein
• Temp., thermister probe –
rectal,esophageal
or nasopharyngeal

20. MONITORING…..
• Ventilation
– Airway pr.monitoring,
– O2 analyser
– Mass spectrography
– Infra red capnograph
• Blood gases-
– SPO2, ETCO2, blood glucose & electrolytes

21. MONITORING…..
• Blood loss
– Small vol.suction traps,
– Swab weighing,
– Serial Hct estimation
• Urine volume
– Urinary catheter & collecting bag
• Above all, trained anesthesiologists eyes , hands &
ears are indispensible.

22. ANESTHESIA
• Major decision is whether or not the neonate needs
post-op ventilation & resuscitation.
• If post-op ventilation is needed, anesthesia
technique is of little importance, any tech. which
maintains BP & oxygenation is acceptable.
• If extubation is planned, anesthesia tech. is very
crucial.
• GA + Regional tech. with epidural Bupivacaine
0.25 %, 1 ml./kg with adrenaline is good.

23. ANESTHESIA….
• Regional block reduces doses of muscle relaxants,
narcotics & recovery will be good.
• Post-op pain relief can be planned
• All new borns must be intubated unless it is a
very minor procedure
• Consider them always ‘full stomach’
• Rapid sequence induction- no need of priming
with NDMR before DM. No fasciculations, no rise
of pressure with DMR.

24. INDUCTION
• It is to eliminate stress,
• CVS stability,
• To secure airway & ventilation,
• To prevent aspiration.
• Gastric pH at birth is 6.0; after 6 hrs. it is
2.5

25. INTUBATION
• It can be awake, or anesthetised.
• Indications for awake intubation:
– Very sick patients
– Anesthesiologist inexperienced in pediatric
anesthesia
– H/o apnoea or respiratory distress,
– Full stomach.

26. INTUBATION…..
• Complications of awake intubation:
– Arterial hypertension,
– IVH
– Apnoea,
– Obstruction to breathing,
– Desaturation & bradycardia
• Deep inhalational induction & 2% xylocaine spray
followed by intubation
• Intubation after paralysing with SUXA 2mg/kg
(controversial) , or NMDR & cricoid pressure.

27. INTUBATION…..
• Preoxygenation for 2 mts.is a must,
uncuffed ET , 20-40 cm/H2O pressure, no
pillow under the head & head extended.
• MAINTENANCE:
• Good oxygenation, prevention of stress due to pain
by short acting narcotics, intermittent inhalational &
muscle relaxants.

28. Maintenance…
– Intra – op fluid therapy:
• 0.2 % saline with 5% dextrose closely resembles the
obligatory fluid of neonate
• 4 ml/kg/hr. ( hyponatremia if given more)
• Better to use 0.45 % saline c 5% Dx.
• RL for 3rd space losses
• More 5% Dx causes hyperglycemia which leads to IVH due to
diuresis, cell dehydration & severe hyperosmolality.
• 5% Dx should not exceed 15-20ml/kg
• Serial estimation of glucose is necessary.

29. Maintenance…
• 3rd space losses in NEC, Omphalocele &
gastroschisis can exceed patients blood volume.
• CDH , congenital heart patients may not tolerate
larger vol.
• Interstitial edema develops
• Serial estimation of Hct , proteins , osmolality ,
electrolytes & urine output help in accurate
replacement of fluids.
• Neonate can tolerate 10% of blood loss
• Transfusion reactions like coagulation defects,
temp. changes, metabolic problems occur early in
neonates

30. RECOVERY
• Recovery is quick ,
• Extubation without good recovery causes
laryngeal spasm,
• Rx with IPPV , head extension , mandible thrust.
• If desaturation occurs ( < 85% ) IV suxa &
intubation.
• Don’t wait for cyanosis & bradycardia!
• Strong inspiratory efforts c obstruction causes pul.
edema,
• NMJ block must be reversed fully until active
movements of all 4 limbs occur
• Temp. must be > 35 0 C before reversal.

31. POST-OP PERIOD
• Most vulnerable period ,
hypoxia ,
laryngospasm &
cardiac arrest are common.
• Respiratory depression: Due to
– Apnoea
• Prematurity , narcotics , anesthetics , incomplete reversal ,
hypothermia , concomitant antibiotics &
hypermagnesemia –(PIH)
apnoea is more common below 41 weeks of PCA
upto 4th mth.

32. POST-OP PERIOD…
Hypoxemia due to
– Hypothermia , sepsis & acidosis.
• Rx:
FiO2 for 1st 24 hrs., monitor SaO2
• In conditions c reduced FRC like peritonitis,
int.obstruction, massive transfusions, correction of
omphalocele & gastroschisis-
minimum of CPAP should be provided

33. POST-OP PERIOD…
• Pre-op lung problems like RDS , pulmonary
dysplasia needs active ventilation.
• NMJ transmission impairment
• Hypotension may be due to hypovolemia or
residual inhalational agents
• Metabolic complications: hypocalcemia,
hypo & hyperglycemia.

34. Keep your eyes wide open …