Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
An Overview of Neonatal Emergencies Dr. JUNAID M KHAN MBBS.MD.FRCP.FAAP AL-RAHBA HOSPITAL, ABU DHABI, UAE Objectives: 1. To discuss some common baby-killers. 2. To discuss some basic terms. Introduction • For this talk, neonates will refer to infants aged 0-28 days. – Just think of them as “little children.” • They can have pathology of virtually any organ system. Metabolic Cardiac Sepsis Endo Toxins Heme GI Classification • There are many different ways to organize the neonatal emergencies. • This talk will focus on “THE MISFITS” approach. “THE MISFITS” – A Mnemonic • • • • • • • • • • • Trauma/Abuse (NAI) Heart and Lung Endocrine Metabolic disturbances Inborn errors of metabolism Sepsis Formula Intestinal Toxins Trisomies Seizures NAI • • Non-accidental injury (NAI) is the most common cause of infant death outside the neonatal period. The abuser is a related caretaker in 90% of cases. NAI • Signs suggestive of NAI include: – – – – – Caregivers who are intoxicated or high. Inconsistent or implausible history. Multiple (or different aged) fractures. Posterior rib fractures. Unusually shaped/distributed bruises or burns. – Bite marks. NAI • Head injury is the leading cause of death in NAI. • The initial neonatal examination may be surprisingly normal. • Non-specific clues to IC haemorrhage may include: - altered LOC - irritability - FTT - vomiting - seizures - decreased mm tone • Retinal haemorrhages are virtually pathognomonic of NAI in the neonate. Retina hemorrhages “THE MISFITS” • • Trauma/Abuse (NAI) Heart and Lung Heart and Lung • There are numerous cardiac and pulmonary entities which cause neonatal morbidity and mortality. • Many pulmonary issues (eg. RDS, croup, bronchiolitis, pneumonia, etc.) • The focus will be on congenital heart disease. Heart • Congenital heart disease (CHD) occurs in 1/125 live births. • Neonates may present with a variety of non-specific findings, including: - tachypnea - pallor - FTT - cyanosis - lethargy - sweating with feeds • More specific findings include: - pathological murmurs - hypertension - abnormal pulses - syncope Congenital Heart Disease • Neonates with CHD often rely on a patent ductus arteriosus and/or foramen ovale to sustain life. • Unfortunately for these neonates, both of these passages begins to close following birth. – The ductus normally closes by 72hrs. – The foramen ovale normally closes by 3 months. CHD • • That being said, in the presence of hypoxia or acidosis (generally present in ductus-dependent lesions), the ductus may remain open for a longer period of time. As a result, these patients often present to the ED during the first 1-3 weeks of life. – i.e. as the ductus begins to close. Classifying CHD • There are many different classification systems for CHD. – None are particularly good. • I will be discussing the Pink/Blue/Grey-Baby system: 1. Pink Baby – Left to right shunt 2. Blue Baby – Right to left shunt 3. Grey Baby – LV outflow tract obstruction Pink Baby (L R shunt) • L R shunts cause CHF and pulmonary hypertension. • This leads to RV enlargement, RV failure, and cor pulmonale. • These babies present with CHF and respiratory distress. – They are not typically cyanotic. Pink Baby (L R shunt) • These lesions include (among others) ASD’s, VSD’s, and persistently patent ductus arteriosus. VSD ASD Pink Baby (L R shunt) Persistently patent ductus arteriosus Pink Baby (L R shunt) • Diagnosing L R shunts depends on: 1. Examination findings: • Non-cyanotic infant in resp distress. • Crackles, widely-fixed second heart sound, elevated JVP, cor pulmonale. 2. CXR: • Increased pulmonary vasculature (suggestive of CHF). • RA and/or RV enlargement. 3. EKG: • RAE and/or RVH. Pink Baby (L R shunt) • Initial management should be directed at reducing the pulm edema. – Adminster Lasix 1mg/kg IV. • Peds Cardiology/ PICU should be consulted urgently regarding use of: – – – – Morphine Nitrates Digoxin Inotropes Blue Baby (R L shunt) • • • R L shunts cause hypoxia and central cyanosis. Neither hypoxia or cyanosis tend to improve with 100% oxygen. R L lesions include (among others): – – Tetralogy of Fallot (TOF) Transposition of the Great Arteries (TGA) Tetralogy of Fallot • Characterized by: 1. 2. 3. 4. • Pulmonary a OTO RV hypertrophy VSD Over-riding aorta With severe pulmonary OTO... bloodflow to the lungs may be highly ductus-dependent. * * * * Tetralogy of Fallot • • The classic CXR finding in TOF is the boot-shaped heart. Pulmonary vasculature is typically decreased. Transposition of the Great Arteries • • TGA is the most common cyanotic lesion presenting in the first week of life. Anatomically: – – • RV aorta LV pulmonary aa To be compatible with life, mixing of the two circulations must occur via an ASD, VSD, or PDA. Transposition of the Great Arteries • • The CXR findings in TGA are typically less dramatic than in TOF. Pulmonary vasculature is typically increased. Blue Baby (R L shunt) • Hypoxia and cyanosis (unresponsive to oxygen) in the neonatal period suggests a ductus-dependent lesion. • Treatment is a prostaglandin-E1 (PGE1) infusion. – Dosing discussed momentarily • This should obviously be accompanied by urgent Peds Cardiology and consultation. Grey Baby (LVOTO) X • Left-ventricular outflow tract obstructions (LVOTO’s) lead to cyanosis, acidosis, and shock early in the neonatal period. • Complete obstruction is universally fatal unless shunting occurs through an ASD, VSD, or PDA. • Examples of these lesions include: – Severe coarctation of the aorta – Hypoplastic left heart syndrome (HLHS) Grey Baby (LVOTO) • Treatment: – Any neonate presenting with shock unresponsive to fluids +/- pressors has a LVOTO until proven otherwise. – As with the Blue babies, appropriate management is an urgent PGE1 infusion and emergent consultation. Prostaglandin-E1 • • • PGE1 promotes ductus arteriosus patency. Use an IV infusion at 0.05-0.1 ug/kg/min. A response should be seen within 15 min. – If ineffective, try doubling the dose. – If effective, try halving the dose. • The lowest possible dose should be used– as adverse-effects of PGE1 can include: - fever - diarrhea - flushing - periodic apnea (be ready to intubate) RDS • Respiratory Distress Syndrome • Immaturity of Lungs • Need Surfactant • Need Ventilation Reticugranular (Ground Glass) Air Bronchogram “THE MISFITS” • • • Trauma/Abuse (NAI) Heart and Lung Endocrine Endocrine • Several endocrine emergencies can present in the neonatal period. • We will briefly discuss three: 1. Hypoglycemia 2. Thyrotoxicosis 3. Congenital adrenal hyperplasia (CAH) Neonatal Hypoglycemia • This is most commonly seen in the neonates born to diabetic mothers. • During pregnancy, maternal hyperglycemia crosses the placenta to cause fetal hyperglycemia. • The fetal pancreas responds by increasing insulin production. • Following delivery, the hyperglycemic stimulus is instantly removed—but insulin production may take longer to slow down. Neonatal Hypoglycemia • Neonatal hypoglycemia therefore typically arises in the nursery, but could still be seen in the ED. • As with any patient, check a chem strip in any neonate presenting with: - decreased LOC - seizures - resp distress - weak tone - hypotension - cardiac failure Neonatal Hypoglycemia • Glucose < 40(in a symptomatic neonate) or < 30 (in an asymptomatic neonate) should be treated. • Can use 2cc/kg of D10W (repeated prn). • This should be followed by: 1. Searching for an etiology (if not obvious) 2. Repeated glucose monitoring Neonatal Thyrotoxicosis • This is a very uncommon condition— occurring in about 1% of pregnancies of mothers with Graves disease. – The risk in babies born to euthryoid mothers is negligible. • Caused by the placental passage of stimulating TSH-receptor antibodies from the mother to the fetus. Neonatal Thyrotoxicosis • All neonates are screened for thyroid function at birth. – As such, it would be unusual for neonatal thyrotoxicosis to present to the ED. • That being said, potential findings could include: - goiter HR > 160 shock hyperthermia - proptosis dysrhythmias CHF pallor Neonatal Thyrotoxicosis • Appropriate treatment (preferably in consultation with Peds Endo) includes: 1. Beta-blockade – Propanolol 0.1mg/kg IV 2. Blocking thyroxine production – PTU 5-10mg/kg PO 3. Blocking thyroxine release – Potassium-iodide 1-4 drop PO – Only give > 1 hr after giving PTU 4. Decreasing T4 T3 conversion – Dexamethasone 0.1mg/kg IV Congenital Adrenal Hyperplasia • CAH refers to any one of several autosomally-inherited disorders. • These disorders involve a defect in the adrenal production of cortisol, mineralocorticoid, or both. • These defects are caused by a missing or malfunctioning enzyme. • “21-hydroxylase deficiency” accounts for 90-95% of all cases – It wil be the focus of this section. Epidemiology • 21-hydroxylase deficiency is present in ~ 1 in 3500 births. • Because of variable penetrance, clinical effects in the neonate are probably seen in only ~ 1 in 10,00020,000 births. • The incidence of CAH can be 10-100 fold higher in certain populations. – e.g. Ashkenazi Jews CAH • Lack of 21-hydroxylase causes: 1. A build-up of the immediate precursor (“17-hydroxyprogesterone”). • Instead of being converted into cortisol, this precursor is converted into androgens. 2. Another precursor metabolite, progesterone, is prevented from being converted into aldosterone. 21-hydroxylase deficiency • A highly-simplified schematic is shown here. 21-hydroxylase deficiency • Because of variable penetrance of the disease, a neonate with 21hydroxylase deficiency may present with any or all of the following: 1. Cortisol deficiency hypoglycemia, hypotension, and shock. 21-hydroxylase deficiency • Because of variable penetrance of the disease, a neonate with 21hydroxylase deficiency may present with any or all of the following: 2. Aldosterone deficiency hyponatremia, hyperkalemia, and dehydration. 21-hydroxylase deficiency • Because of variable penetrance of the disease, a neonate with 21hydroxylase deficiency may present with any or all of the following: 3. Androgen excess virilization of female genitalia. - Male genitalia are typically unaffected at birth—but may be unusually small. CAH • Other forms of CAH may present similarly to 21-hydroxylase deficiency • However, because of different defects, findings may also include: 1. Androgen deficiency potentially causing lack of virilization of male genitalia. 2. Mineralocorticoid excess potentially causing hypertension and hypokalemia. Treatment of CAH • Patients suspected of 21-hydroxylase deficiency should have the following bloodwork sent: 1. 2. 3. 4. 5. Electrolytes Glucose 17-hydroxyprogesterone levels Cortisol levels Aldosterone and renin levels. Treatment of CAH • After drawing appropriate bloodwork: 1. Pt’s with dehydration, hyponatremia, or hyperkalemia should receive a bolus of isotonic crystalloid to restore volume. 2. Hypoglycemic patients should receive a dextrose bolus +/- infusion. 3. Pt’s suspected of adrenal insufficiency should be treated with steroids empirically (i.e. rather than waiting for the results of confirmatory studies). Treatment of CAH • When administering steroids: – Use an initial dose of HC 1-2 mg/kg IV (followed by q6h dosing) • The disadvantage of hydrocortisone is that it will confound any ACTH-Stim testing. • The advantage of hydrocortisone is that it is a complete steroid—with both glucocorticoid and mineralocorticoid activity. “THE MISFITS” • • • • Trauma/Abuse (NAI) Heart and Lung Endocrine Metabolic disturbances Metabolic disturbances • Remember to send the following bloodwork in any toxic neonate: 1. 2. 3. 4. 5. LFT’s and coagulation parameters Lipase Ammonia Lactate levels pH • Okay... moving on. “THE MISFITS” • • • • • Trauma/Abuse (NAI) Heart and Lung Endocrine Metabolic disturbances Inborn errors of metabolism Inborn Errors of Metabolism • • The inborn errors of metabolism are a group of diverse disorders—usually caused by the lack of a specific enzyme. They include: 1. Urea Cycle Defects 2. Organic Acidurias 3. Galactosemias • • These disorders are rare—affecting only 1 in 100,000-200,000 live births. Unfortunately, they typically present during the neonatal period—and cause irreparable brain injury if missed. “THE MISFITS” • • • • • • • • • • Trauma/Abuse (NAI) Heart and Lung Endocrine Metabolic disturbances Inborn errors of metabolism Sepsis Formula Intestinal Toxins Seizures Sepsis • Much too broad a topic to tackle here. • I will discuss five guidelines pertinent to the ED resuscitation of pediatric severe sepsis and/or septic shock. – Based on Pediatric recommendations from the 2003 “Surviving Sepsis Campaign.” Sepsis 1. Early intubation. – Neonates with severe sepsis may benefit from early mechanical ventilation. – Similar lung protective strategies apply to the neonate once he or she is on the ventilator. – High FiO2’s should be avoided in premies (if at all possible) to prevent retinopathy Sepsis 2. Aggressive fluid resuscitation. – This is fundamental to survival in pediatric septic shock. – There is no strong evidence for the use of colloid over crystalloid (or vice-versa) – Use 10mL/kg IV bolus(es) of crystalloid prn given over 5-10mins. Sepsis 3. Vasopressors/inotropes should be used in septic shock only after appropriate volume resuscitation. – If required, the appropriate vasopressor /inotrope will depend on assessment of CO and SVR. Sepsis 4. Endpoints to resuscitation: a) b) c) d) e) f) g) Normal LOC Cap refill < 2 sec Normal pulses Warm extremities Urine output > 1mL/kg/hr Decreased lactate Increased pH Sepsis 5) Steroids. – No clear consensus for the role of steroids in pediatric septic shock. – Should be reserved for refractory hypotension or known adrenal insufficiency. – Use Hydrocortisone 1-2mg/kg IV (followed by q6h dosing as per Peds Endo). “THE MISFITS” • • • • • • • Trauma/Abuse (NAI) Heart and Lung Endocrine Metabolic disturbances Inborn errors of metabolism Sepsis Formula and Feeding Formula and Feeding Mishaps • Neonates are ideally breastfed. • The neonatal breastfeeding schedule should be “on-demand.” – ~10mins/breast, ~q3h, but ++variable. • The neonate should be allowed ample time to fully drain each breast. – The final dregs of breastmilk (or “hindmilk”) are felt to contain more fat. • The mother’s breasts should feel “empty” following a full feed. Formula and Feeding Mishaps • If formula is used, the feeding schedule is approximately the same – ie. on demand, ~q3h, highly variable. • Hard to make mistakes with jarred baby food (i.e. “insert into baby”). • With powdered formula, make sure it is being mixed appropriately. – Typically a 1:1 ratio. Formula and Feeding Mishaps • Irrespective of the type of feeding, neonatal signs of satiety should be sought after a meal. • These can include: 1. Decreased irritability. 2. Falling asleep. 3. No longer “rooting” or sucking. Formula and Feeding Mishaps • Always ask about potentially dangerous feeding behaviours: 1. Feeding the neonate inappropriate substances (i.e. pop, juice, Coffeemate). 2. Feeding the neonate water. – Neonates should not get any – supple-mentary water until 6 months (or older) – Water lacks nutritional content but causes satiety decreased food intake. 3. Lack of money to afford proper food. “THE MISFITS” • • • • • • • • Trauma/Abuse (NAI) Heart and Lung Endocrine Metabolic disturbances Inborn errors of metabolism Sepsis Formula Intestinal Intestinal Emergencies • At last count, there were ~ 1 million pediatric intestinal emergencies. • I will focus on one such emergency specific to the neonate: necrotizing enterocolitis (NEC). • NEC is characterized by the mucosal or transmucosal necrosis of part of the intestine. • The exact etiology is unknown. Necrotizing Enterocolitis • NEC is the most common intestinal medical/surgical neonatal emergency. – It affects 1-2 neonates per 1,000 births. – Most commonly seen in preemies—but can also be seen in term neonates. – Mortality ranges from 0%-100% depending on the stage of prematurity and severity of disease. Necrotizing Enterocolitis • Premies remain at risk for NEC for several weeks after birth. – Onset is typically while the neonate is on advancing enteral feeds. • With term babies, the onset of NEC is generally in the first 1-3 days of life. – Term neonates who get NEC are usually already ill from another condition. – e.g. congenital heart disease, lung disease, metabolic abnormalities, etc. Necrotizing Enterocolitis • Initial symptoms can include: • feeding intolerance • abdominal distension • +/- hematochezia • This can progress to: • • • • lethargy apnea DIC shock and cardiovascular collapse Necrotizing Enterocolitis • Lab findings can include: • • • • • abnormal WBC thrombocytopenia hyponatremia elevated PT/PTT metabolic acidosis Necrotizing Enterocolitis • The mainstay of ED imaging studies is the abdominal X-ray. • It can reveal a variety of non-specific findings including: – dilated bowel loops. – thickened bowel walls. • However, the finding of pneumatosis intestinalis is pathognomonic for NEC. • • Pneumatosis intestinalis is the presence of air bubbles within the bowel wall (caused by extravasation of air from the lumen.) It has a characteristic train-track lucency appearance on AXR. Necrotizing Enterocolitis • Free air is not pathognomonic for NEC. – In the context of NEC, however, free air indicates the need for urgent surgery. • Free air in the neonate may be best detected with a left lateral decubitus (ie. left side down) view. – Look for free air above the liver shadow. Intestinal Emergencies • Management of NEC depends on the severity of illness. • The Bell staging criteria have been developed to help guide therapy. – Stage 1: Suspected disease • Mild, non-specific clinical and radiological findings. • +/- grossly bloody stool. – Treatment is NPO and antibiotics for 3d. Intestinal Emergencies • Management of NEC depends on the severity of illness. • The Bell staging criteria have been developed to help guide therapy. – Stage 2: Definite disease (Medical NEC) • Pt is mildly to moderately ill • Findings can include abdominal pain, mild acidosis, pneumatosis intestinalis - Treatment is NPO and antibiotics for 7 14 days Intestinal Emergencies • Management of NEC depends on the severity of illness. • The Bell staging criteria have been developed to help guide therapy. – Stage 3: Severe disease (Surgical NEC) • Pt has severe findings that can include gross peritonitis, hematological abnormalities, free air, et cetera. - Treatment is NPO x 14d, ICU support, +/- paracentesis or open laparotomy. “THE MISFITS” • • • • • • • • • Trauma/Abuse (NAI) Heart and Lung Endocrine Metabolic disturbances Inborn errors of metabolism Sepsis Formula Intestinal Toxins Toxins • There’s lots of them. • It takes less of them to kill a neonate. • Remember to consider: a) Maternal toxins (ie. if breastfeeding). b) Environmental toxins (eg. cigarette smoke, carbon monoxide). c) Abuse (ie. Munchausen by proxy). “THE MISFITS” • • • • • • • • • • Trauma/Abuse (NAI) Heart and Lung Endocrine Metabolic disturbances Inborn errors of metabolism Sepsis Formula Intestinal Toxins Seizures Seizures • There have been few striking new developments in the world of acute neonatal seizure management. • First line medications remain BZP’s. • Phenobarb is preferred as a 2nd-line agent over phenytoin in patients under the age of 1-2 yrs. – Phenytoin has a myocardial depressant effect and unpredictable metabolism in the neonate. Seizures • Other investigations and management strategies include: • Stat ABG/VBG (with lytes, Hb, & lactate). • Full set of labwork including LFT’s, ammonia, urine and blood cultures. • Empiric antibiotics +/- Acyclovir prn. • Head U/S or CT Seizures • There are several forms of benign neonatal convulsions—but these are unlikely to be diagnosed. • Remember that the differential of seizures in a neonate essentially includes all of the other MISFITS. Trisomies • Trisomy 21 (Down’s Syndrome) • Trisomy 18 (Edward’s Synd) • Trisomy 13 (Patau’s Synd) Putting It All Together 1. Basics. – IV, O2, monitors, vitals, foley, +/- NG 2. Stat chem strip and ABG/VBG (with the works). 3. Stat EKG and CXR. Putting It All Together 4. Labwork. – If possible, draw bloodwork at the start of the resuscitation. – Remember blood and urine cultures. – Remember ammonia and lactate levels. • Both of these must be stored on ice and rushed to lab. – Remember to draw a “red-top tube” if an inborn error of metabolism is suspected. Putting It All Together 5. Administer empiric antibiotics. – Make sure all cultures are drawn first. – LP’s are typically postponed in the acute phase. – A reasonable empiric regimen might be: • Ampicillin 100mg/kg IV • Cefotaxime 50/mg kg IV • Acyclovir 20mg/kg IV Putting It All Together 6. Examine EKG. – If a life-threatening rhythm is present, treat as per PALS guidelines. 7. Examine sats. – If sats are <85% despite 100% O2 (especially if centrally cyanotic), start a PGE1 infusion at 0.05-0.1ug/kg/min. Putting It All Together 8. CHF suspected? – If CXR or clinical examination reveal evidence of CHF, give Lasix 1mg/kg IV. – Consult Peds Cardio regarding: • Use of digoxin, nitrates, inotropes. • Admission. Putting It All Together 9. NAI suspected? – Order a skeletal survey +/- CT of the head/ab/pelvis. 10. Clinical jaundice or bilirubin > 340? – Arrange admission for phototherapy. Putting It All Together 11. Inborn error of metabolism suspected? – If not already done, draw a red-top tube. – Begin IV fluids and glucose. – Consult Peds Metabolics. Putting It All Together 12. CAH suspected? – Draw cortisol, 17-hydroxyprogesterone, aldosterone, and renin levels. – Begin IV fluids and glucose. – Treat elevated K as necessary. – Give hydrocortisone 1-2mg/kg IV. Putting It All Together 13. Suspicion of NEC or history of bilious vomiting? – Order an abdominal x-ray. – Consult Peds GI or Peds Surgery. Putting It All Together 14. Continue resuscitation as necessary. – Consider additional fluid bolus(es). – Consider inotrope/pressor support. – Consider PRBC 5-10mg/kg (if blood loss is suspected). – Consult as appropriate.