PYLORIC STENOSIS• Incidence:1 in 2000• Male > female (first male child)• Preterm = full term• Etiology:Autonomic N system imbalance & humeral disorder(?)• Pathology : gross thickening of circular smooth muscle of pylorus---gradual obstruction of gastric outlet.
PYLORIC STENOSIS• Diagnosis: clinical: projectile vomits, mass in upper abd. (‘olive in abdomen’) upper G.I.series with barium Ultrasound• Anaesthetic concerns: - dehydration - acid-base abnormalities -risk of aspiration
PYLORIC STENOSIS• Pathophysiology: Hypochloremia, hypokalemia, hyponatremia & metabolic alkalosis.• Preparation: Medical emergency- parameters for surgery: normal skin turgor, Na>130mg/l k at least 3meq/l, Cl <85 meq/l urine output 1-2ml/kg/hr Resucitation c balanced salt soln, pot chlor after urination.
PYLORIC STENOSIS• Induction of Anesthesia: -preoxygenation with 100% O2 - Ryles tube asspiraton -Pentathol – 5 mg/kg. -Suxa2mg/kg…intubation -surgeon needs relaxation twice a) at the time of delivery of pylorus b)at the time of putting pylorus into abdomen
– Atracurium 0.5 mg/kg-best nondepolarizing relaxant after induction followed by caudal epidural 1.25ml/kg bupivacaine 0.25% with 1:200000 adrenaline. – Reversal as usual• Post-op care:respiratory depression is common.
Tracheo - Esophageal Fistula,with/without Esophageal Atresia1. Incidence-1:3-4.5000 births 20-25% assoc. with VSD,ASD,TOF,Coarctation of aorta. another 20-25% with TEF are premature wt<2kg
Tracheo Esophageal Fistula,• Anatomy/Classification: – Mostly TEF &EA occur together – 90% lesions are type’C’ – i.e. fistula between trachea & lower esophagus above carina.upper esophagus ends blindly.
Tracheo Esophageal Fistula,• Associated anomalies: – TEF with other anomalies in 30-50% pts. – VATER association – 1973 by Quan & Smith • V- vertebral defect / VSD • A- anal defect • T-TEF • E- atresia • R- radial dysplasia / renal dysplasia
Tracheo Esophageal Fistula• Diagnosis: – Early diagnosis is imp.to prevent pulmonary complications- which determines prognosis. – In utero-polyhydramnios- – At delivery-pt.has excessive salivation,drooling, cyanotic spells, cough-relieved by suction. – Resp.depression – Inability to pass a catheter(feeding tube#8) – X-ray-radioopaque cath ending in proximal esophagus- simple & diagnostic
Tracheo Esophageal Fistula,• Pre-op management: – ‘has the baby suffered any pulmonary insult’? Aspiration pneumonia-more morbidity-delay the procedure; stomach decompression by gastrostomy – Avoid feeding – Nurse in propped up position – Intermittent suction – Antibiotic therapy & physiotherapy – Hydration
Tracheo Esophageal Fistula,• Surgical management: – Primary repair in 24-48 hrs. – Gastrostomy under LA, delay thoracotomy for 48-72 hrs.,which allows proper hydration & assessment of resp. & CVS.• Anesthetic considerations: – Pre-medication:inj.atropine IM. – OT- AC off, warmers kept ready,(heat loss is more in thoracotomy). – Monitors:ECG,BP,FIO2,pulse oximetry,rectal temp,arterial line,foley cath,precardial steth.
Tracheo Esophageal Fistula – Induction /intubation. • Decompression of stomach (gastrostomy tube allowed to vent, & kept at head end of patient), • Pre-oxygenation • Awake/anesthetic intubation • Correct position of ETT • Induction with N2O+O2+ halothane • IPPV cautiously attempted before NMJ blocker. – ETT might enter fistula during intubation,or during surgery difficulty in ventilation saturation and ETCO2
Tracheo Esophageal Fistula,• Maintenance: – Continue inhalational agents.discontinue N2O if gastric dilatation occurs – Non depolarising muscle relaxant , conc of halothane –less CVS depression – O2 conc by ABG sampling. High FiO2 if pulmonary pathology is present. – Manual ventilation best- changes can be detected easily. Airway obstruction can occur during surgery & due to accumulation of blood & secretions in tube. – Blood loss 20-30%. If Hct <30,and EBL >10-15%,vol. replacement with blood. – IV fluids for maintenance
Tracheo Esophageal Fistula,• PostOperative care: – Analgesia by caudal 0.25% bupivacaine1.25ml/kg with epinephrine1:200000.Postop. ventilation if necessary (prematurity, RDS, CHD)• Complications: – Esophageal dysmotility,esophageal stricture,recurrent URI&LRI, tracheomalacia, gastroesophagreal reflex.
CONGENITAL DIAPHRAGMATIC HERNIA• Incidence: 1:4000 live births mortality with heroic post-op measures-30% (earlier 40-50%)• Def: herniation of abdominal contents into chest through a defect in the diaphragm. – Types: Lt.posterolateral defect in foramen of Bochdalek(75-85%) - commonest – anterior opening (foramen of Morgagni) -rarely
CONGENITAL DIAPHRAGMATIC HERNIA…• Associated anomalies: still borns c CDH – 95% of other anomalies live borns –20% CVS (esp. PDA) defects• Clinical presentation: variable – Early hernia,pressure on lung bud small lung – Hernia in late fetal life normal lung,but compressed infants c severe hypoplasia symptoms in 1st hour less severe forms symptoms in 24 hrs.
CONGENITAL DIAPHRAGMATIC HERNIA…• Diagnosis: antenatal:1) 30% c polyhydramnios 2) ultrasound after delivery: x-ray chest• Anesthetic considerations: delay surgery till infant stabilises (24-48hrs.to 1week)…levin 1987
1. Pre-op care:– Decompress c nasogastric tube– Don’t ventilate c mask– Awake intubation paralyse, sedate, ventilate c 100% O2– Lowest possible inflation pressure (30cmH2O) used (vs.-in pneumothorax)– Tr.of acidosis-ventilation,soda bicarb,improve circulation by fluids& inotropes
CONGENITAL DIAPHRAGMATIC HERNIA… 2.anesthetic management: – Intubation & paralyses before arrival to OT,or preoxygenation-rapid sequence awake intubation-low airway pressure & high resp.rate – Frequent blood gas estimations,ET CO2 & pulse oximetry-maintain effective ventilation – Prevent hypothermia – Low conc.of inhalational agent c high inspired O2 or high doses of narcotics (fentanyl). Avoid N2O – Primary closure of abdomen,or chimney prosthesis,or silastic pouch – Continue paralysis & controlled ventilation post-op, except in infants c small defects & good gas exchange .
CONGENITAL DIAPHRAMATIC HERNIA… Options: – in infants c severe lung dysplasia,tr. c ECMO preop, wean then schedule for surgery – Repair defect when on ECMO & maintain ECMO post-op for 30 days – Neonates c CDH have surfactant deficiency, using ECMO will improve surfactant
CONGENITAL DIAPHRAGMATIC HERNIA… – Pts. given ECMO with NO before & after ECMO & after surgery. NO was ineffective pre-ECMO. NO after ECMO followed by surgery was able to increase oxygenation. (Karamanaoukian et al.) – UK study- pts. c CDH not treated c ECMO but c preop stabilisation & supportive care had same results as c ECMO therapy. – ‘what is the best time to operate? operation should be postponed till PVR is decreased as revealed by Doppler EchoCardiography.
CONGENITAL DIAPHRAMATIC HERNIA…• Post-Op problems: – Determination of outcome • a) extent of Pulmonary Hypoplasia • b) degree of pulmonary hypertension Infants with post-op PaCo2 < 40mm.Hg. who could be hyperventilated c airway pressure < 20 cm. H2O , & who had a resp.rate < 60 /mt. survived well.(Bohn.,J.Paediatrics,1984) Reducing PVR & prevention of Rt.to Lt. Shunt is accomplished by ----- hyperventilation, ligation of PDA & drugs include tolazoline, PGE1, & ECMO.
INTESTINAL OBSTRUCTION• Upper GI obstruction: – Persistent bilious or non-bilious vomiting deficit of fluids & electrolytes.(Stomach contains 100-130 meq/l/Na.,& 5-10 meq/l of K. – To prevent aspiration, awake / RSI.• Anesthetic considerations: – Pre-op preparation- • Correction of dehydration • Correction of electrolytes • Ryles tube decompression
INTESTINAL OBSTRUCTION• Anesthesia: – Awake, rapid sequence intubation – Repair of congenital defect & closure of abdominal defect. – N2O can be used.• Extubation – Possible only with good g.c. – Patient debilitated,extensive surgery,big incision, – Post-op ventilation c PEEP.
INTESTINAL OBSTRUCTION• Lower GI obstruction: – Problem develops between 2-7 days – Incomplete anus can be evident after birth – Vomiting secondary to obstruction electrolyte or fluid disturbances.Large fluid sequestration within GI tract, (ECF c high Na+ content) – Na must be >130meq/l , & urine volume of 1.2ml/kg/hr.
INTESTINAL OBSTRUCTION• Anesthetic considerations: – Decompression of stomach – Electrolyte & fluid management – Awake, rapid sequence intubation – N2O should not be used. – Adequate relaxation – If patients g.c. is good,reverse & extubated with post- op O2 supplementation – If patients g.c. is not good, post-op ventilation is continued c PEEP.
OMPHALOCELE & GASTROSCHISISOmphalocele:• herniation of intestine into base of umbilical cord.Gastroschisis:• defect of abdominal wall lateral to base of umbilicus• Incidence: omphalocele-1:10000 births gastroschisis – 1: 30000 births boys : girls 1:1 25-30% are premature or LBW
OMPHALOCELE & GASTROSCHISISOmphalocele:• membrane covering peritoneum inside, amniotic membrane outside.• Sac may be small or large containing liver,spleen etc.• Prematurity 25-30%• Associated anomalies:77%
OMPHALOCELE & GASTROSCHISISGastroschisis:• Eviscerated abdominal contents,involves small or large lntestines• Umbilical cord is to left of defect• Prematurity is 58%Anesthetic considerations:• Pre-op management: – Search for associated anomalies, – Ruptured omphalocele is a surgical emergency.
• Fluid resuscitation: – Fluid loss is high, – 3rd space loss,protein loss, increased fluid requirements – 150-300 ml / kg / day RL or 5% Albumin is used. – Correct acid – base status – Insensible loss – wrapping the child in polythene bag filled c warm saline.
OMPHALOCELE & GASTROSCHISIS• Atropine• Temperature regulation• Hypoglycemia & hyperglycemia are avoided.• Nasogastric tube for decompression of stomach.
OMPHALOCELE & GASTROSCHISIS• Peri-operative management: – Monitoring – Induction c I.V. inhalation – Awake intubation• Maintenance: – FiO2 to maintain saturation of 95-97% – N2O should be avoided, – Maintenance by balanced anesthesia, – Airway pressure to be monitored – Post-op ventilation for 24-48 hrs. – Excellent skeletal muscle relaxation – Repair is staged if primary closure is not possible
OMPHALOCELE & GASTROSCHISIS• Post-op complications: – Respiratory insufficiency – Ileus, – Venacaval compression due to tight closure. – Sepsis is major cause of mortality & morbidity – Temperature regulation
NECROTISING ENTEROCOLITIS• Clinical Signs: – Retained gastric secretions, – Vomiting , bloody , mucoid diarrhea, – Thermal instability, – Abdominal distension c bloody, sticky stools – Signs appear in first few days of life/2or 3 days after feeding – Lethargy & apnea, metabolic acidosis, jaundice, – DIC c prolonged PT & APTT. – X-ray abdomen: early – distended gas filled loops, – Late gas in the bowel., (pneumatosis intestinalis ).
NECROTISING ENTEROCOLITIS…• Non – surgical management: – Decompression of stomach, – Cessation of feeding, broad spectrum antibiotics, – Fluid & electrolyte therapy – Ionotropic agents, steroids in septic shock• Indications for surgery: – Peritonitis, air in portal system, ascitis,progressive deteriotion.
CONGENITAL LOBAR EMPHYSEMA…..• Anesthesia: – Crying, struggling amount of trapped air – IPPV emphysema – Halothane + O2 c mask , intubation c or c out relaxation. – IPPV postponed until thorax is opened.( cote,1978) – Extubated at the end of lobectomy. – Humidity, coughing mininises atelectasis in post-op period, – Results are good.
REFERENCES• 1. Wylie & Churchill Davidsons : – ‘A practice of anesthesia’ ; 6th Ed.,Chapter 30th by James.M.Steven & John Downes.• 2. Physiology of the neonate of importance to anesthesiologists , by Frederic.A.Berry, M.D., 42nd anesthesiology review course lectures.• 3. Emergency neonatal surgery , by Frederic.A.Berry, M.D., 42nd anesthesiology review course lectures.• 4. Anesthetic management of neonatal emergencies, by Anna Lucia Pappas, M.D., asst.prof. Loyola University Medical Centre.