Neonatology - Lecture Note

Neonatology Teratogens Rubella (before 8/40) à PDA / peripheral pulmonary stenosis, cataracts, deafness Fetal alcohol syndrome à upto 70% cardiac lesions = ASD/VSD/ToF, Coarc + facies (long, featureless philtrum) + developmental delay Phenytoin à craniofacial anomalies, nail anomalies, cardiac lesions (AS/PS, coard & PDA) SLE à heart block Lithium à Ebstein’s Anomaly = abnormal tricuspid valve with leaflets stuck to ventricular wall, ASD, inlet of RV becomes aterialised. Cyanosed infant with FTT & prone to SVTs. Long systolic murmur + diastolic murmur. May require Nitrous oxide or duct reopening. Neonatal presentation = poor prognosis Perinatal Mortality Includes still births > 22/40 (Total mortality / live + still births) x 1000 Size at Birth Large for date (over 90th centile) Usually maternal DM à fetal hyperinsulinaemia, increased risk of congenital abnormality, birth injuries, hypoglycaemia, RDS, jaundice. Tend to be jittery à feeding problems Low Birth Weight (under 10th centile) 60% stillborn, 70% die in 1st week, can be due to prem, maternal drug/alcohol, multiple pregnancy, poor placental function, intrauterine infection etc. Small for Date Increased risk of perinatal hypoxia & hypoglycaemia, can à learning difficulties Birth Injuries Caput seccedaneum Oedematous bruising to head/face – usually clears spontaneously in few days If in face can à bloated, blue, bruised with retinal & conjunctival haemorrhages + possibility of traumatic cyanosis with cord around neck Cephalohaematoma Denting / # of skull ~ size of hens egg – may take months to disappear Supaponeurotic Haemorrhage Bleed spreads rapidly over head, can be significant volume of blood Tentorial Tear Due to severe compression/extreme moulding à permanent damage/death Erbs Palsy Damage to brachial plexus – usually transient (resolves in approx 10 days) Polyhydramnios Maternal DM Rh Incompatibility 20% will have some form of defect 22% congenital heart disease 40% GI tract malformations e.g. duodenal / oesophageal atresia 26% NTD Twin –Twin transfusion Syndrome Placenta vascular anastomosis ONLY occurs with monochorionic twins 5g/dl difference in Hb AND 20% difference in birth weight Survivor may develop DIC RX – digoxin / selective termination / laser ablation of anastomosis Respiratory Problems Lung Mechanics DONOR Oligohydramnios Small Prem Malnourished & low BMs Pale Anaemia Hypovolaemia Small glomeruli Thin wall arterioles RECIPENT polyhydramnios Large Prem Well nourished Plethoric Polycythaemic Increased vol & cardiac failure Large glomeruli Thick walled arterioles La Place Law P = 2T / r Therefore pressure to keep an alveolus open is related to Tension (i.e. compliance) and inversely related to radius (therefore if lung collapses V down à needs more pressure to reopen Compliance Low compliance area = poor change in V for high P If over stretched à also poor compliance Aim to keep ventilator pressure in area of linear compliance Ventilators & Blood Gases pH pO2 pCO2 BE Bicarb Sats CPAP 7.35 – 7.45 (anything >7.25 is acceptable) 8 – 10 aim for maximum 10 in prems 4–8 If too low à vasoconstriction à brain ischaemia upto -7 18-25 88-95% to avoid excess pO2 re ROP (re O2 dissociation curve) Continuous Positive Airways Pressure = splints airway open. Usually use pressure between 4 & 8 cm Can use SiPAP – sets 2 levels, patient triggered = better step down from vent Works better in prems – term babies tend to fight Works well via nasal prongs as babies are obligate nasal breathers Uses Resp distress – but exclude pneumothorax 1st CLD Weaning from ventilator Contraindications Severe apnoeas Needing FiO2 > 60% Upper airway abnormality (e.g. choanal atresia, TOF) CVS instability Unstable resp drive Complications Pneumothorax Gastric distension ( CPAP belly) & vomiting Hypercapnia Pressure necrosis from prongs / mask P Cerebellar haemorrhage & skull deformity if tight mask Nasal secretions & mucus plugs Nasal septal erosions Weaning CPAP Shown to be better to wean pressure rather than length of time off CPAP EVIDENCE COIN – CPAP v Intubation + surfactant – No diff in death / CLD. CPAP has higher pneumothorax but lower CLD. 46% tried on CPAP will need ET CURPAP – CPAP v Intubation + surfactant – NO difference in need for mechanical support. CPAP has LESS pneumothorax, 50% tried on CPAP will need ET SUPPORT – CPAP v Inubate & surfactant – No difference in death or CLD. No difference in pneumothorax. CPAP showed more alive & less on support at 7d & overall shorter vent. Also less need for PN steroid VENTILATION Pressure limited – set maximum pressure, therefore tidal volume depends on compliance Volume limited –set a tidal volume, pressure will increase accordingly V Pressure limited Above PIP will lead to volutrauma Below PEEP will lead to atelectruma (collapse & reopening sheering forces) Therefore try to keep within the 2 à oval flow volume loop V P V Volume limited PEEP PIP P Constant high pressure à overdistension Asynchrony – out of sync with ventilator Venturi’s Law The sum of the colliding forces in a linear tube is inversely proportional to pressure laterally on wall Therefore working against vent à pressure on walls à air leaks, inadequate gas exchange & higher thoracic pressure on vessels à raised BP à IVH due to poor cerebral autoregulation 10cmH2O Sum = 2 12cmH2O 10cmH2O Sum = 6 16cmH2O To avoid asynchrony à paralyse baby (& use IMV) or use synchronised ventilator (uses pressure / flow sensors / neural sensory (NAVA)) SIMV P Synchronous Intermittent Mandatory Ventilation Only supports a maximum number of ventilations Forces breath in, allows breath out Always maintains PEEP (+ve end expiratory pressure) PTV = Patient Triggered Vent (SIPPV = Assist = PTV (diff brands)) Synchronised Intermittent PPV Supports ALL breaths baby tries to take Therefore less time at PEEP thereforeless atelectrauma Typical starting settings • 18/5 (PIP / PEEP) • Rate 60 • Ti 0.35 therefore... • Te=0.65 • FiO2 as required Pressure support – Baby controls Ti, Rate & onset. Machine gives pressures as set Volume guarantee – set tidal volume. Vent adjusts pressure to deliver vol = weans own pressure as lungs improve compliance Adjusting Ventilators Increasing PEEP à decreased tidal volume à increased CO2 Low pO2 Increase FiO2 Then increase Mean Airway Pressure = area under ventilator curve Increase PIP & PEEP Avoid increasing rate >60 as à barotraumas High CO2 Increase minute volume = rate x volume Increasing PIP will increase tidal volume (usually 4-6mls/kg) Weaning ventilator Decrease pressure Then rate (minimum 20) Then give caffeine to stimulate respiration Then extubate onto CPAP High Frequency Venitilator (HFOV) Small tidal volumes (0.1 – 5 mls / kg) & pressure (0.1 – 20mmH2O) Rapid rate (180 to 1200) High end expiratory lung volume Inhaled Nitric Oxide Therapy For hypoxaemic respiratory failure Causes potent pulmonary vasodilatation (without affecting systemic BP) No evidence for use in Prems NO can be synthesised from GTN, Nitroprusside & from L-arginine By macrophages, lymphocytes & endothelial cells Is a neurotransmitter as well as vasodilator Has short T1/2 when given inhaled Acts via cGMP (PgI2 acts via cAMP & causes plt aggregation) ExtraCorporeal Membrane Oxygenation (ECMO) Artificial lung circuit allows lung rest Passive drainage from RA Veno-venous à increases O2 content, returns blood to RA Veno-arterial à can also increase cardiac output, Uses R IJV & Common carotid (Often ligated as part of procedure) UAC / UVC UAC – avoid tip at renal / celiac axis (L1) therefore L2-5 = safe or T6-10 is ideal UVC - Respiratory Distress <60 breaths/min, recession, flaring, grunting, head bobbing, cyanosis in air Must be 2 or more for > 4 hours Transient Tachypnoea of Newborn Commonest cause of respiratory distress (1-2% of all babies) Benign, self limiting, usually fully resolved within 48 hours “Wet lung” = Delay in clearance of amniotic fluid, Cause – failure to absorb fluid (should be squeezed out or absorbed by lymphatics & capillaries) Risk factors C-section babies (within 4 hrs) esp if not in labour – as catecholamines aid reabsorption Early gestation (“late preterm” 34-38 weeks) Male Maternal DM or asthma Fetal asphyxiation Breech S&S: tachypnoea, grunting, cyanosis, RR > 40, may require supplemental O2, usually start to improve within 6 hours CXR – streaky shadows from mediastinum + fluid in horizontal fissure, sometimes also pleural effusion & cardiomegaly Treatment - Usually settles rapidly in few hrs, mild O2 requirement. Occasionally needs CPAP to force fluid out, can restrict fluid to 60mls/kg until resolving Intrauterine Pneumonia Consolidation @ birth, assoc with prolonged membrane rupture/fetal hypoxia Organisms – 60-70% are GBS, others inc E.coli, H.Influ, S. Pneum, Listeria CXR – patchy consolidation Difficult to differentiate initially with other causes therefore treat everyone Meconium Aspiration Meconium present at 10% term deliveries MAS = 2/1000 – more likely if Afro / asian, postmature or fetal compromise S&S: tachypnoea, hypoxia, hypercapnia, cyanosis soon after delivery CXR patchy collapse & consolidation (meconium plugs airways) Complications Air leak – ball valve effect – 15-30% PPHTN – 67% Death – 5-12% Also causes chemical irritation to airways Prevention Aim to delay 1st breath until suctioned NB: aspiration usually occurs in utero due to gasping action of stressed fetus Treatment Avoid ventilation as à hyperinflation Supplemental O2 (aim for Sats >95%) Suction Maintain BP > 45mmHg May require extre surfactant (mec inactivates surfactant) If severe may need inhaled Nitric Oxide or ECMO Milk aspiration Common in preterm babies / with cardiac or neuro problems Respiratory distress syndrome Previously known as Hyaline Membrane disease Pathophysiology = Insufficient surfactant production (should be stimulated by uternine contractions, can be artificially produced with steroids) Surfactant From type II pneumocytes = phospholipid, stored in lamellar bodies. Main active component is Lecithin à reduces surface tension Lung maturity can be measured by L/S ration of amniotic fluid (from amnio/ gastric lavage). If <1.5 = 70% RDS, 15-2.0 = 40% RDS Produced from 30-32 weeks Risk Factors Usually in pre-terms (but not exclusive, can get surfactant deficient genes) Infant of diabetic mother APH 2nd Twin Hypoxia, acidosis & shock – all reduce surfactant Male Pre-labour C-sect Clinical Course Obvious within 1st 6 hours, infant tires due to effort of re-expanding lungs Copious pharyngeal secretions Increasing O2 requirement Apnoea = late sign & can indicate infection Initial oliguria with increasing peripheral oedema At approx 48hrs has dieresis with clinical improvement CXR Ground glass appearance on CXR with air bronchogram Rx Antenatal steroids stimulate surfactant production Exogenous surfactant via ET tube (porcine / bovine) Use as prophylaxis / rescue treatment Complications Air leak Bronchopulmonary dysplasia PDA & pulmonary HTN Cerebral haemorrhage & periventricular leucomalacia NEC ROP (due to O2 treatment) Prognosis If < 500g = 100% incidence = 10% survival 500g-1kg = 80% incidence but 80% survival 1-1.5kg = 55% incidence, 95% survival >1.5kg = 20% incidence but 100% survival Chronic Lung Disease / Bronchopulmonary dysplasia Healing phase of premature lung problems – mostly RDS but can be anything requiring ventilation Diagnosis – O2 requirements and CXR changes by 28 days old OR at 36 weeks corrected Severe = pressure dependent (CPAP etc) Mild = <30% O2 Risk factors / Causes Low birth weight 34% if <750g 20% if 750 – 1000g 5% if 1kg – 1250 3% is 1250 - 1500 More common in boys, lower incidence in black babies Ventilator trauma – Pressure & Vol trauma à inflammation & cytokine release COIN trial showed in 25-28/40 CPAP vs Vent makes no difference to CLD Oxygen toxicity – immature cells have low anti-oxidants therefore free radical damage Inflammation & Infection – often reason for prem is chorioamnionitis – placenta infection, raised maternal CRP & Temp à activates mum’s cytokines à cross placenta à lungs Ureaplasma infection – certain strains à 3x higher risk of CLD PDA – fluid overload to lungs à inflammation & damage Antenatal steroids are partially protective Relates back to stages of lung development • Canalicular = 16-24 wks –mesenchyme proliferation à growth on bronchioles • Terminal Sac stage = 22wks onward – formation of alveoli with gas exchange surface à thinning of blood-gas barrier. o Type 2 pneumocytes produce surfactant from 24 wks • Alveolar from 29/40 Clinical Features – persistent chest retractions, crepitations & rhonchi. Hyperinflation of chest & increased AP diameter Mostly have PDA & may develop cor-pulmonale Histological changes Hyaline membranes, Eosinic infiltration, Collapsed air spaces & congested vessels Progresses to fibrosis with muscle hypertrophy in media layer, irregular aeration, decreased septation of alveoli à smaller surface area Graded by radiology 1 – Day 2-3, Acute RDS, Granuloreticular pattern, air bronchograms or white out 2 – Day 4-10, period of regeneration, near / total opacification 3 – Day 10-20, period of transition, small cystic infiltrates, chronic disease 4 - >4 weeks, chronic disease, hyperlucency, strand like infiltrates, enlargement of cysts Treatment Early surfactant Diuretics – reduces interstitial lung fluid (pulmonary oedema). Start after 2-3 weeks, monitor U&Es. Short term improve O2 & gas exchange. Poor evidence for long term use Dexamethasone – reduces O2 requirement in babies with CLD. Use after 2/52 old if remaining ventilator dependent due to neuro side effects (increased risk of CP). ALSO increases sugar & BP, infections risk and decreases growth Prednisolone – used to wean from CPAP or High flow O2 Inhaled steroids – DONT WORK Inhaled nitric oxide – NO evidence Reducing oxygen toxicity BOOST I trial showed: In <30/40 babies 91-94% O2 v 95-98% O2 Made no difference to growth But less O2 meant less time in hospital & £££ BOOST II (Benefits Of Oxygen Saturation Targeting) In <28/40, randomised at <12hrs old (up-to 24 if home birth) Does 85-89% v 91-95% affect... • Death / severe disability @ 2yrs • And 20 outcomes of ROP, CLD etc Prospective meta-analysis trial to prevent bias from studies not published due to not proving hypothesis No difference in lower O2 sats in lung outcomes but better side effects (ROP etc) Antioxidants e.g. vit A shown to reduce BPD & death. Optimise nutrition – need to grow therefore start TPN early BPD spells – episodes of rapid desaturation requiring bagging. Occur if out of synchrony with ventilator. Likely due to bronchomalacia / tracheomalacia. Manage by sedate & intubate then rewake slowly. Will improve with age Prognosis – often have viral wheeze. Majority asymptomatic by 2 years with normal CXR by 23 yrs. Resp function tests are abnormal for years. Increased risk lower airways infection in 1st year , esp bronchiolitis. Use Palivisumab as prophylaxis Persistent Pulmonary Hypertension Failure of adaptations at birth à R à L shunts remain in place à pulmonary resistance remains high Can be secondary to diaphragmatic hernia, idiopathic, hypoxia or acidosis Rx – O2 à decreases pulmonary vascular resistance Pulmonary Hypoplasia Can be due to failure of fetal breathing e.g. neuromuscular, obstruction e.g. hernia or lack of liquor (oligohydramnios / Potters) Resp distress from birth with hypoxia, hypercapnia & metabolic acidosis Diaphragmatic Hernia 1/2200, 80% are left sided Failure of muscle to develop à persistent plueroperitoneal canal Diagnosis Often diagnosed antenatally, otherwise presents within 24hrs of birth Mediastinal shift, scaphoid abdomen, CXR=bowel loops in chest (usually LHS) Assoc with malrotation & cardiac problems Rx: NOT bag&mask (resp distress as air swallowed), intubate & ventilate, NG tube to empty stomach surgical repair Prognosis – Survival dep on degree of pulmonary hypoplasia. If resp distress in 1st 6 hrs = 70% mortality If presents 6-24hrs = 10-15% mortality Pulmonary Haemorrhage Assoc with asphyxia, hypothermia, surfactant therapy Starts around d3-6 Cardiovascular collapse with blood stained fluid from mouth Usually fatal Causes Haemodynamic – e.g. large PDA à increased pulmonary flow Haematological e.g. DIC (assoc with other bleeds e.g. brain) Rx: Only remove ETT if blocked (keep ventilated – PEEP will reduce further bleeds), Volume expansion FFP & transfusion Diuretic Apnoeic attacks Common in prems & sick neonates CPAP / ET tube if prolonged • Sepsis • Reflux • Electrolyte disturbance • Anaemia • Convulsion • IVH • Prematurity (diagnosis of exclusions) Pneumothorax Occur in 1% of all infants, 10% of these are symptomatic (= 1 in 1000) Due to high pressures First few breaths extreme pressures (Inspiratory pressure 52.3cmH2O, Expiratory 71.3cmH2O) Ventilators Can rarely be due to underlying bullae Risk factors Stiff lungs (e.g. hyaline) Hyperinflation (e.g. meconium) Hypoplastic lungs (e..g Potters) Mechanical Ventilation / CPAP (esp prolonged Ti, high PIP & asynchrony) Diagnosis Clinical - asymmetry, mediastinal shift and respiratory distress Diagnose by cold light illumination, CXR is not essential Management Can be conservative 100% O2 (nitrogen washout) will speed reabsorption, but risk of eye damage If tension pneumothorax will need decompression & drainage (2nd IC mid clav) Can also get pneumomediastinum, pericardium, pulmonary interstitial emphysema (air in interstitium) or air embolus Effusions Can be isolated e.g. chlothorax Or Generalised e.g. Hydrops (generalised oedema + involvement of 2 mucosal surfaces) Tracheo-oesophageal Fistulae Assoc with oesophageal atresia Approx 1 in 4000 births Symptoms - Choking & drooling, maternal polyhydramnios if no connection for oesophagus (60%), Milk aspiration Diagnosis – X-ray with 10F NG in situ to show blockage (will stop approx 10cm). Check AXR for gas – indicates if any connection Complications – aspiration of bile & gastric contents into lungs à pneumonia & collapse Can be assoc with other developmental anomalies e.g. VACTERL (vertebral, anal, cardiac, tracheal, oesophagus, renal & limb Management – nurse 60 degree head up. TPN until surgery Congenital Cystic Adenomation Malformation (CCAM) Males > Females Abnormal differentiation à can have abnormal vascular / cystic elements. Lined by cuboids / bronchial epithelium Associated with polyhydramios, hydrops, prematurity & stillbirth Diagnosis – often found antenatally, DONT show on CXR Can à high output failure & respiratory distress Type 1 = 70%, single / multiples large cysts in 1 lobe Type 2 = 18% multiple medium sized cysts Type 3 = 10% = large bulky lesion with evenly distributed small cysts Rx – lobectomy even if asymptomatic as risk of Ca. Can be treated with fetal surgery! Congenital Lobar Emphysema Intrinsic air trapping with bronchial narrowing Due to cartilage deficiency of lobar bronchus Can be acquired to mucus plug Difficult to diagnose before birth m>f 1/3 present at birth Can be acquired e.g. post RSV infection 50% = Left Upper Lobe, 24% Right Middle, 18% Right Upper 30% assoc with congenital heart disease e.g. Fallots, VSD or TAPVD Symptoms – collapse slowly over 2-3 weeks due to lung collapse around affected lobe Diagnosis Hyperlucent distended lobe & mediastinal shift Decreased breath sounds & hyperresonant percussion NO perfusion on VQ scan Rx lobectomy if problematic – NOT premalignant Choanal atresia Anterior nares fail to form Crying à pink, settle à blue RX - surgery Pierre-Robin Syn Triad of • Midline posterior cleft palate • Hypoplastic mandible • Upper airway obstruction secondary to tongue position Mild cases will improve if laid prone. Try NP airway. May need tracheostomy Usually resolve as jaw enlarges with growth GI Problems Necrotising Enterocolitis Acquired bowel disease Inflammatory disease with ulceration & can à perf Most commonly affectes terminal ileum / sigmoid Pathophysiology Mucosal injury Asphyxia PDA (à steal syndrome) Polycythaemia (slow flow) Anaemia – poor O2 to gut Severe IUGR / VLBW – compromised flow during development Absent / reverse end diastolic flow UVC & UAC Cyanotic heart disease Hirschsprung’s – due to local mucosal ischaemia Enteral feeds NEC almost never if never fed More common if formula (rather than EBM ? protective effect of IgA etc) More common if rapidly increased feed volumes Infection Organisms such as coliforms, staph, clostridium & rotavirus seem to predispose Gas forming organisms invade bowel wall à air in wall Clinical Features Non specific – Lethargy, Apnoeas, Brady’s, Failure to maintain temp, irritable Gastro - Abdo distension with visible loops & discolouration, Bilious aspirates, discoloured stools, Blood & mucus in stool Systemic – shock, resp failure Circulatory collapse Complications DIC Septicaemia (1/3 of cases) Bowel perf à peritonitis or local abscess à football sign with air in biliary tree Bowel obstruction Gangrenous bowel Lactose intolerance & malabsorption in recovery period Relapse after restarting feeds Intra-hepatic cholestasis (due to TPN) Investigations X-ray – intramural gas (pneumatosis interinosus) & distension à signs of perf FBC – neuts up or down, thrombocytopenia Micro – faeces & blood Diagnosis – definitive only at autopsy / histology from surgery Classification 1 – Suspected (a. Non specific GI Sx, b. + blood in stool) 2. Definite (a. + intermural gas, b. + systemic sx) 3. Advanced (a. + severe systemic sx, b. + perf) Prevention Antenatal steroids à less RDS à less ischaemia Delay milk feeds in high risk babies Use breast milk over formula NO EVIDENCE for oral Abx or oral Ig Possible probiotics – under study at present Treatment NBM, TPN & 10d Abx Optimise O2, FBC & clotting etc If continue to deteriorate / perf à SURGERY Complications of surgery include short bowel, stricture, latose intolerance & recurrence Complications Death (up to 40%) Short Gut Relapse Stricture Complications of prolonged TPN Neuro impairment (linked to surgery – CP, neuro dev delay etc) Congenital diaphragmatic hernia 1/2000, 80% on LHS (30% have other abnormalities inc malrotation & heart defects) Often detected with US antenatally Respiratory distress as air swallowed à compression of lung and mediastinal shift RX: plan delivery in centre with ECMO. NG tube to deflate stomach à surgical repair. Can be poor prognosis if pulmonary hypoplasia Intestinal obstruction Assoc with polyhydramios Suspect if can aspirate more than 25 mls from stomach at birth Symptoms Bile stained vomiting = obstruction below D2 Distension – more common with lower obstruction Visible peristalsis Delayed meconium Dehydration à collapse Oesophageal Atresia 1/2500 – assoc with tracheo-oesophageal fistula Must be excluded if hydramnios, assoc with anorectal & cardiac probs Dx: Pass NG tube, air in stomach = confirms fistula, unable to swallow saliva Duodenal obstruction If complete à Early vomiting Intrinsic Duodenal atresia – 50% assoc with T21, rest have CVS / anorectal anomalies Duodenal stenosis – can be due to septum or membrane Extrinsic Malrotation / annular pancreas Diagnosis Plain film shows double bubble If air beyond = suggests Malrotation Treatment Surgical repair. Often poor motility after anastomosis à TPN req Malrotation (volvulus neonatorum) Due to incomplete fixing & rotation after 8-10/40 3 main features: Duodeno-jejunal junction to RIGHT of vertebral column Ileocaecal junction near midline & higher than normal Fixed by avascular Ladd’s bands across D2 è small bowel is abnormally mobile à volvulus with occlusion of SMA à strangulation & Ladds bands obstruct D2 80% occur in-utero / neonatal period Symptoms Episodic obstruction with distension, bilious vomits, pallor & a vague abdominal mass Diagnosis X-ray shows double bubble with distal gas Contrast shows corkscrew duodenum with abnormal caecal position US shows abnormal vascular arrangement Treatment – urgent laparotomy Jejunal Atresia ½ of intestinal atresia are jejunum (commonest) or ileum Can be one or more segment missing Often found on antenatal scan Sx – rapid distension Xray – multiple loops & fluid levels. Peritoneal calcification = meconium peritonitis Rx – resect & anastomose Colonic atresia < 10% of bowel atresia Present in 2nd or 3rd day Contrast enema shows microcolon Anorectal malformations 1/5000, M> F Assoc – with GU / vertebra / upper gut anomalies Can be high (above levator ani) or low (below) Girls often have fistula to vagina, boys to bladder Ix – X-ray spine & sacrum for bony errors. IVU / Other contrast study Mx – Low = good prognosis with local reconstruction 1/3 have normal continence 1/3 have acceptable continence with some soiling 1/3 are incontinent High = poor prognosis Colostomy followed by rectoplasty at 6-12 months Often have incontinence Large Bowel Obstruction Hirschsprungs (aka congenital aganglionic megacolon) Absence of ganglion cells in myenteric plexus (plexus of Auerbach) - derived from neural crest à tonic contraction of a bowel segment (starts at internal anal sphincter & runs proximal) è dilatation of section of bowel è increased intraluminal pressure è decreased blood flow & decreased mucosal barrier function è statis of gut contents è increased bacterial load è enterocolitis & sepsis with obstruction Commonest cause of large intestinal obstruction in neonates = failure to pass 1st meconium in 48 hours (90% of babies will pass mec in 48hrs) or thin stringy stools Only 15% cases present as neonates 1/4500 births Short segment – 85-90% cases M:f = 4:1, usually rectum / sigmoid Long segment – 10-15% M:f = 1:1 with high familial risk (12.5% if sibling = Chr 10) 20% Assoc with other syndromes: Downs Lawrence-moon-bardet-biedl syndrome Smith-Lemli-Opitz syndrome Waardenburg sysndrome Cardiovascular anomalies Central hypoventilation Presentation On examination – PR à normal anal tone & explosive release of foul smelling faeces & flatus In older children can present as constipation with overflow NEVER have normal bowel habit Ix: anorectal manometry / unprepared Ba enema (shows narrowed segments), suction biopsy (shows increased ACh activity. Rx: colostomy to excise the anglionic segment, with anastomosis later Comps: entercolitis is common pre and post-surgery. Meconium plug syndrome Obstruction à passage of white plug of meconium à recovery Can be hirschsprungs / IUGR / CF Meconium Ileus 90% of meconium ileus is CF 10-15% of CF presents as meconium ileus After surgery, IRT falls rapidly therefore can get false negative on CF screening. So take screening test before surgery Rx – gastrograffin enema / surgical decompression Anterior Abdominal Wall Defects Exomphalos (omphalocele) 1/6000 Defect occurs around 18/40 when bowel fails to return to abdo Peritoneal covering & cord from apex of defect = THROUGH umbilicus 60-80% have associated defects e.g. CHD, Trisomies 13 or 18, Beckwith-Wiedermann syndrome (+ large tongue & low BMs) Diagnosis – on US, also raised alpha feto-proetin. à chromosomes Management – plastic wrap to keep bowel warm & moist. NGT & IVI at 1.5 x maintenance. Surgery 2-4 hours after birth. < 5cm à primary closure, > 5cm may need staged repair Complications – splinting of diaphragm on returning bowel to abdo, also compression of vena cava & renal failure Gastroschisis 1/3800 More common in young primips Rarely assoc with other syndromes Protrusion of bowel through abdo wall – usually RHS of umbilicus. NO peritoneum à bowel is scarred & matted from contact with amniotic fluid. Often adhesions, strictures, atresias & poor motility Management – bowel into saline filled bag at birth & surgery ASAP Problems – IUGR, failure to thrive & short gut. Often need TPN PR bleeding in neonates Swallowed maternal blood à Apt’s Test to tell fetal from maternal blood Rectal / anal fissure (from thermometer / PR / constipation) NEC - xray Benign haemorrhagic colitis Assoc with mucus. Mainly formula fed infants, due to cow’s milk intolerance Malrotation / intussusecption - xray Meckels – isotope scan Gastroenteritis – rotavirus / shigella / salmonella / e.coli - cultures Rectal polyp Haemorrhagic disease of newborn – ensure IM vit K Most settle with no cause found CNS problems Causes of brain injury in Term infants Hypoxic Ischaemic Encephalopathy (birth asphyxia) Biochemical e.g. persistent hypoglycaemia True BM < 2.6 Can à jittery / floppy, irritable, convulsions High risk if growth retardation / prem / DM mum / mum on B blocker e.g. hyperbilirubinaemia à kernicterus e.g. metabolic errors e.g. galactosaemia, urea cycle disorders Infection – e.g. meningitis, encephalitis e.g. herpes can à SEM disease, CNS disease or disseminated disease Vascular – bleeds Inflammation Birth Asphyxia Hypoxia + hypoperfusion à acidosis & local tissue damage Can affect any organ e.g. renal – acute tubular necrosis e.g. liver – coag disorders e.g. gut – increased risk of NEC e.g. myocardial ischemia à decreased cardiac output à worsens ongoing hypoperfusion e.g. brain à HIE Monitoring for asphyxia CTG / scalp pH (pH should be > 7.25, if < 7.2 à deliver baby urgently) Cord Gases (no accepted normal values. Generally accepted pH < 7.1 = bad) Apgars Subsequent neurology e.g. movements, tone etc Newborn response to asphyxia: Apgar 0-3 at >5min Neurological sequelae (early encephalopathy, hypotonia, seizures, coma) Multi-organ system dysfunction (e.g. kidneys, liver, heart) Cord pH <7.0 (arterial) Cord arterial base excess >16mmol/L Birth Asphyxia severe enough to cause cerebral palsy ** Only 10% of CP is due to birth asphyxia Evidence of metabolic acidosis at delivery (pH < 7, BE > -12) Early onset of encephalopathy Spastic / dyskinesia pattern to CP Exclusion of other causes To demonstrate occurred in labour to a previously healthy baby Sentinel event e.g. APH, cord prolapse, fluid embolism etc Fetal distress (on CTG or scalp pH) Evidence to exclude other causes (e.g. infection, metabolic & intracranial events) For parents to prove liability Prove could be detected An unnecessary delay occurred Another mechanism of delivery would have been faster WITHOUT major risk to mother Causes of Neonatal Depression Drugs à resp depression e.g. anaesthetics, opiates, MgSO4 Placental Failure à Hypoxia & acidosis e.g. PET, IUGR, Praevia Haemorrhage à hypovolaemia e.g fetomaternal transfusion, Abruption Developmental à cardiac / pulmonary insufficiency e.g. diaphragm hernia Oligohydramnios à pulmonary insufficiency e.g. PROM / Potters Physical / mechanical à interrupted blood supply e.g. cord entrapment, cord prolapsed Severe immaturity à pulmonary insufficiency e.g. RDS / poor resp effort Post maturity à meconium / placental deterioration e.g. PPHTN, Mec Environmental à Hypothermia e.g. unplanned home birth Iatrogenic à hypoxia, vagal stimulation, excessive ventilation e.g. pulmonary air leak, incorrect intubation Extrinsic pulmonary compression à pulmonary insufficiency e.g. pleural effusion, pulmonary hypoplasia Precipitate delivery à birth trauma e.g. intracranial haemorrhage PPROM à Perinatal infection, pneumonia Sequelae of birth asphyxia Metabolic Metabolic acidosis – can mimic RDS Inappropriate ADH secretion Respiratory RDS – increases severity & reduces surfactant deficiency TTN – worsens Meconium aspiration Cardiac Myocardial ischaemia – with tricuspid insufficiency & congestive failure. Flat / inverted T waves, ST depression, abnormal Q waves & sometimes complete bundle block. Raised cardiac enzymes PPHNT Patent Ductus Arteriosus CNS = HIE (Sarnat & Sarnat grading) Grade 1 = Mild 1.6% à death / severe handicap Increasing irritability, poor tone, poor suck. Appear hyper-alert but feed poorly NORMAL EEG Recovers COMPLETELY by 3 days Grade 2 = Moderate 24% à death / severe handicap Marked lethargy, lack of interest in feeding. 70% will have Mild seizures develop between 12 & 24 hours. Hypotonia, proximal weakness, low resting HR Small pupils, copious secretions EEG abnormal MUST IMPROVE during 1st week to be allocated to this group Grade 3 = Severe 78% à death / severe handicap Initially breathe normally but rapids ventilator dependent Profound low tone Multiple seizures, difficult to control Areflexia ABNORMAL EEG with decreased background Renal Treatment Optimise oxygenation Treat correctable items e.g. sepsis, coagulopathy Aim to reduce / prevent cerebral oedema Hypothermia for 72 hours can be protective 33-34°C for 72 hours as shown in TOBY trial. Requires CFM monitoring before & during NB: 30% of cerebral palsy due to birth asphyxia Commonly oliguria (<1m/kg/hr) If extreme à anuria Also haematuria & proteinuria with raised creatinine GI – Increased NEC risk Prevention: Recognise high risk Monitoring e.g. Doppler, HR Use of antenatal steroids Treatment Supportive – BM, acidosis, seizures, respiratory Treat – DIC, Renal failure Cautious feeds to avoid NEC COOLING 33-34oc, for 72 hours, starting within 6 hours of birth è 20% risk reduction of HIE Cerebral Function Monitoring (CFM) Used to assess severity of HIE, assess response to cooling and confirm HIE seizures Uses 3 or 4 electrodes à single channel of EEG Interpreting Amplitude = upper and lower margin of dense section (exclude brief spikes) Normal Upper limit > 10mV, Lower limit > 5mV Moderate abnormal (broad) Upper > 10mV but lower < 5mV Severe abnormal (narrow) Upper < 10mV lower < 5mV Seizures Sudden rise & narrowing of trace with regular wave on EEG trace Periventricular leukomalacia “softening of the white matter” MAJOR risk factor for developing CP Due to damage to oligodenroglial cells in Periventricular white matter during 26-34 / 40 Causes Thought to be due to ischaemic brain injury occurring in watershed areas of MCA (adjacent to lateral ventricles – can also affect corticospinal tract). Risk factors – TTTS, Maternal chorioamnionitis (cytokins as neurotoxins), severe asphyxia e.g. cord prolapsed, severe lung disease e.g. tension pneumothorax, hypocarbia, NEC & Dexamethaone given in 1st 96 hours Diagnosis – US shows echodense areas in white matter. Can resolve / progress to cysts / cavities. Intracranial Haemorrhage Common finding at autopsy (70%) 5 types 1. subarachnoid Most commonly 2o to IVH tracking through ventricles 1o SAH is common & usually & benign in prems &terms (due to hypoxia / trauma). Sx – usually no Sx, but can have seizures / apnoeas Dx – US = Poor, MRI / CT better. CSF heavily bloodstained & doesn’t clear Prognosis – good if minimal Sx & predisposing injury is mild. 90% of those with seizures will be normal on FU Rx – check Coag, shunting rarely required 2. Subdural Previously common due to birth trauma, now rare Due to rapid changes in head shape during delivery Common incidental finding in ventouse babies Can be due to: • tentorial laceration (with rupture of straight sinus) à intratentorial • falx cerebri laceration & rupture of inferior sagittal sinus à haematoma of longitudinal fissure • rupture of superficial cerebral veins with subdural over temporal lobe (usually assoc with SAH) Predisposing factors include – rigid birth canal, large head, rapid / prolonged labour, abnormal presentation, difficult forceps, ventous Clinical features - tense fontanelle, hypotonia, lethargy, facial palsy. If posterior fossa then apnoea & bradycardia. Can also be asymptomatic Ix – US if large. MRI / CT better Rx – subdural tap may be required 3. Intraventricular Blood in ventricles May be due to germinal matrix haemorrhage or choroid plexus haemorrhage. Vascular area around ventricles = sub-ependymal germ layer. Present until 32 weeks. Capillary bleeds into this area = PVH Incidence - 33% in < 1500g, rare in term babies Risk factors – prem, RDS, IPPV, hypercapnia, metabolic acidosis, coag disorder Due to poor cerebral autoregulation Features • 60% have no major Sx. Can have subtle tone change / slow nystagmus • Intermittent deterioration over several days with apnoeas, bradys, metabolic acidosis & seizures • Massive collapse – shock & coma = rare. More likely to be sepsis Diagnosis – US = Ix of choice Grading 1. Subependymal germinal matrix haemorrhage 2. IVH with no ventricular dilatation 3. IVH with ventricle distended by blood 4. Intraparenchymal Complications Porencephalic cysts (due to grade 4 PVH). Healing à fluid filled spaces with communicate with the ventricles. Development affected based on location Post haemorrhage hydrocephalus – blood affects drainage à blockage. Rx with diuretics, acetazolamide and isosorbide Treatment / prevention No Rx available Prevention = control of risk factors 4. Intracerebral 80% due to venous infarct 2o to IVH or rebleed into veriventricular ischaemic areas. Otherwise due to coag / cerebral aretery occlusions / TORCH / thalamic haemorrhage / AV malformation ro tumour 5. Intracerebellar Only in 5% of infants = rare Neonatal seizures Most occur secondary to hypoxia, electrolyte imbalance, infection or bleed Types can be subtle (e.g. chewing / sucking / cycling), tonic, clonic, tonic-clonic or myoclonic Causes The neonatal brain is predisposed to seizures (excess of excitatory & deficiency of inhibitory neurotransmitters) Hypoxia disrupts pathway à increased risk Immature myelination & axonal development à increased risk HIE – 50% of cases. can be subtle with lip smacking, cycling limbs or generalised. Clues in birth history. At risk of renal and hepatic problems. Usually improve & cease by d5 Intracranial haemorrhage – If SAH will be neuro normal between. Infection – most commonly Gr –ve bacilli, GBS & TORCH Withdrawal – in < 10% of withdrawal Metabolic – can occur early or late Mainly low BM or low Na or Low Ca. Can be kernicteric If > 72 hrs consider inborn errors of metabolism Neonatal stroke – often protein C / protein S deficiency 5th day fits – benign condition, unknown cause. Self limiting. Seizure syndromes Ix – Hx, OE, BM, electrolytes, LP, Septic screen, US, Urine & Serum AA, U.org acids, serum lactate & ammonia, Gal-1-put Rx – ABC Is the child well ? (Buys time to Ix) Is the child Dysmorphic? Treat underlying cause. If life threatening 20-30mg/kg phenobarbitone Then phenytoin if no effect. 3rd line usually midazolam Neural Tube Defects (1/1000) – See neurology notes for more details Post natal US = 86% sensitive, 93% specific. MRI is better Anencephaly Absence of brain tissue, most stillborn / die in a few days Cranium Bifidum Defects Defect in skull (with/without protruding meninges/brain) Spina Bifida Occulta Usually Asymptomatic & present in up to 20% of normal individuals Hairy patch / birthmark / Dimple with non visible base Can à mild spastic gait / bladder problems Spina Bifida Cystica Meningocele = lumbosacral, good prognosis, surgery in first few days Myelomeningocele = prognosis dep on severity, can be no functioning distal Often lower limb anaesthesia & paralysis, neuopathic bladder & bowel Hydrocepalus without Spina Bifida Due to aqueduct stenosis or infection/haemorrhage (inc NAI) Monitor head circumference, Shunt fluid to atria / peritoneum NB Sacral dimple = common finding in natal cleft. NOT assoc with OSD (occult spinal dysraphism). DONT require FU or Ix Cleft Lip & Palate Cleft Lip 1/1000, m>f, Unilateral (70% are Left side) or Bilateral Risks Polygenic (occasionally AD), 3-5% sibling risk, increased in older mums Assoc with Alcohol & anticonvulsants Assoc with 35% have associated anomalies If severe midline cleft à risk of holoprosencephally (assoc with T13) Management Counselling etc. Surgery approx 6-12 weeks Cleft Palate 70% also have cleft lip Variations Complete hard & soft palate Submucous cleft – often with bifid uvula Simple soft palate Features Poor feeding, with milk from nose Aspiration à pneumonitis Management Council parents, feeding aids(teat & squeezy bottle) Ensure hearing screen - frequent ear infections Repair lip at approx 3 month & palate at 9-12 month (before speech) Pierre Robin Syndrome Hypoplasia of mandible with 2o cleft palate Assoc with airway obstruction. Nurse the baby prone Jaw grows rapidly, then surgically repair cleft Treacher Collins syndrome Micrognathia, deformed ears (80%) and deafness (40%) Also CATCH 22 (Di George), Goldenhaar Syn & Fetal Phenytoin syn Infections Group B Streptococcus If symptomatic infection à 10-20 % mortality Can cause: meningitis, Pneumonia à 50% ground glass appearance, 30% patchy pneumonia Pneumothorax, PFC, ARDS, Arthritis, Osteomyelitis Conjunctivitis is rare 95% of late infections are caused by GBS type III Neonatal antibiotic choices AVOID ceftriaxone as displaces bilirubin from albumin Cefotaxime has good CSF penetration (but poor listeria action) Ampicillin = good listeria action Gentamycin = gram negative cover Congenital CMV Periventricular calcification Jaundice Choroidoretinitis, microcephaly, deafness, purpura, pneumonitis Diagnosis by serum IgM & urine virus Hydrops Fetalis Severe & generalised oedema & fluid in at least 2 visceral cavities Immune – Rh / ABO incompatibility Non-Immune Severe chronic anaemia in utero – feto-maternal haemorrhage, homozygous a-thalassaemia, chronic fetomaternal transfusions / TTTS Cardiac failure – severe congenital malformation, premature closure of FO, large AV malformation, fetal SVT Hypoproteinaemia – renal disease e.g. nephrosis, renal vein thrombosis, congenital hepatitis Infections (intrauterine) – syphilis, toxo, CMV, parvovirus (via anaemia) Congenital malformations – CCAM of lung, obstructive uropathy, achondroplasia, pulmonary lymphangiectasia, gauchers Genetic abnormality – T21, 13 or 18, Turners, Triploidy, Noonans Miscellaneous – maternal DM, umbilical . chorionic vein thrombosis, fetal neuroblastomatosis, Chagas, choriocarcinoma Idiopathic = 50% Management Full investigations of above causes Paracentesis Overall poor prognosis Sodium & Potassium Balance Sodium Metabolism Term infant needs 2-3mmol/kg/day Prems need more due to immature renal tubules à loss (5-6mmol/kg/day for 1st week) Hyponatraemia <125 mmol/l Can à apnoea & convulsions Causes Maternal Hyponatraemia due to IV fluids in labour Inadequate intake D&V Excess inappropriate IVI for baby Inappropriate ADH CCF (e.g. in PDA) Diuretics Indometacin Renal failure Sepsis CF Bowel obstruction CAH (salt losing variety) Rx – depends on cause If excess water – fluid restrict If loss then replace Na required (mmol) = 135-actual Na x wt x 0.5 Hypernatraemia Sodium > 150mmol/L Causes Reduces renal excretion - more likely if prem Excess water loss – usually transdermal Excess Na in IVI Dehydration D&V Bowel obstruction (NEC) Osmotic dieresis (hyperglycaemia) Excessive NaBicarb Congenital hyperaldosteronism Faulty making up of formula Treatment – slow correction with IVI Hyperkalaemia K+ > 6.5mmol/l If > 7.5 can à arrhythmias Causes – renal failure, acidosis, shock, hypoxia, blood transfusion Treatment calcium resonium enema if > 7.5 Salbutamol infusion Insulin infusion if > 8 (0.1U / kg AND 1g/kg of IV glucose) Hypokalaemia <2.5 Causes Diuretic treatment Alkalosis Inadequate intake of potassium D&V CAH Rx - replace Vitamin K deficiency Either presents early (first few days) Or late (around 3/12)