1、Approach to the sick Infant,Arun Abbi MD,Neonatal Physiology/Anatomy,Infants have different Physiology and anatomy than adultsThey are dependant on their primary caregiver for hydration and nutritionThey are also unable to communicate to adults and therefore often present later in the course of an i
2、llness They have less cardiorespiratory reserve than adults,Airway,1. Primarily a Nasal Breather This is relevant when an infant presents with URI Sx and has trouble breathing due to nasal congestion 2. Larger tongue Makes intubation harder prone to upper airway obstruction when bagging and when inf
3、ant becomes obtunded,Breathing,Normal Respiratory rate for Newborns - 30 - 60 /min Infants (1-6 months) - 30 - 50 /minTachypnea, Accessory muscle use and Grunting are signs of Respiratory distressFEEDING is the most physically demanding thing that infants do.When they present with diseases causing r
4、espiratory compromise, they stop feeding - this is a sign of a SICK INFANTBRADYCARDIA - late sign of hypoxia,Circulation,Normal HR - Neonate- 90 - 150 Infant - 100 -130 BP - (70 + 2 X age) Neonate - 60 - 80 - syst Infant - 80 - 100Infants can not increase their stroke volume. They increase their car
5、diac output by becoming tachycardic (compensatory mechanism of shock),Circulation,The Ductus closes in the first 2 weeks of life Infants with right to left shunts will present with cyanosis. Infants with left to right shunts will present with CHF (coarctation of the Aorta, VSD, ASD),Circulation,Sign
6、s of Shock 1. LETHARGY 2. POOR FEEDING 3. DELAYED CAP REFILL 4. HYPOTHERMIA 5. TACHYCARDIA 6. HYPOTENSION (Late Sign),Metabolic,The infant has diminished glycogen stores and a high metabolic rate. Hypoglycemia is a common symptom for a sick infant when they are not feeding CHECK A CHEMSTRIP in an in
7、fant who has not been feeding for 12 hrs and is lethargic Hypoglycemia - glucose 4 cc/kg of D10WInfants have a high surface area to body weight ratio This predisposes them to hypothermia due to much greater heat loss,Approach to the sick infant,Perform an initial brief assessment and determine LOC a
8、nd stability Get a chemstrip quickly while getting the history Hx from time of discharge till ED presentation Discharge weight/gestational age Length of labour Rupture of Membranes Group B step? FEEDING HX (how much and how often),Assessment,Overall appearance Alert versus lethargic Vital signs Font
9、analle Cardiac exam/peripheral pulses Abdomen Tender Palbable liver? Genitals Any ambiguous genitalia?,Differential Diagnosis,There are a multitude of different causes for a SICK APPEARING INFANT 1. Infection 2. Cardiac diseases 3. Metabolic disorders 4. Gastrointestinal disorders 5. Child abuse,PNE
10、UMONIC FOR SICK INFANT,THE MISFITS T rauma H eart disease and Hypovolemia E ndocrine M etabolic (electrolyte disturbance) I nborn Errors of Metabolism S epsis F ormula Mishaps (under/overdilution) I ntestinal Catastrophes (volvulus,intussusception,NEC) T oxins and poisons S eizures,Case 1,6 day old
11、male presents with increased lethargy and decreased feeding for 24 hours Mother brings in child to ER Patient born at term NSVD (no complications,Exam,Child appears mildly jaundiced Child is slightly lethargic but not irritable Vitals RR - 46 P - 144 BP 73/35 T - 36.2 Sat 95% (RA),Labs,BGL - 4.4 WBC
12、 - 13.2 Neuts 9.5 Lymphs - 3.6 CH6 - normal Bili - 404 (normal 340),What do you want to do?,1. Phototherapy 2. Send home and encourage more breast feeding with formula supplementation 3. More tests,Tests,Cath Urine Moderate bacteria 10 - 20 wbcCXR - nil acute,LP,WBC - 150 RBC - 1 Gram Stain - gram n
13、eg rods,Treatment,Ampiciliin - 50mg/kg/dose Q6hCefotaxime - 50mg/kg/dose Q6hConsider acyclovir 10mg/kg if conerned about neonatal herpesNo Dexamethasone for neonates,Infection,Bacterial UTI, pneumonia, Meningitis. Group B strept, Listeria, E Coli, StaphViral RSV, enterovirus, neonatal herpes,Infecti
14、ons,Infants will present with lethargy, poor feeding, tachycardia and tachypnea They may have a fever (38.0 C) or be hypothermicInfants do not have the ability to localize infections till about 3 months of age. Meningitis cant be ruled out clinically 3 months of age,Infections,UTI is the most common
15、 infection Get a catheter specimen if an infant is sickRespiratory infections present with tachypnea, grunting/wheezing (RSV)Meningitis will have nonspecific signs and will be diagnosed on LP Bugs - Group B Strept, E coli, Listeria,Infections,Treat infants if they appear sick Drugs -Amp/Gent Cefotax
16、ime/ampicillin,Case 2,10 day old male who presents to the ER with decreased feeding for 24 hours Mother states the child has only taken 4 oz in the last 24 hours Child had one bloody mucousy BM Born at term and no complications,Case 2 Exam,Child appears lethargic Pt is tachypneic with some accessory
17、 muscle use,Case 2 Contd,Any Concerns?What do you want to check?What else do you want to know?,BGL - 1.1,Treatment of hypoglycemia,Give 4 cc/kg of D10W (10% glucose) and reassess BGL Q 30 minutes,CXR,Mild increased perhilar markings,DDX,Query pneumonia versus cardiacPatient has a palpable liver and
18、has diminished pulses peripherally,Case 2,Cardiac Diseases,The Patent Ductus Arteriosis closes and 7 - 14 days. Infants with Right - Left shunts present with cyanosis - not relieved with oxygenInfants with Left - Right shunts/ Coarct present with signs of CHF,Cardiac Diseases,Other presentations can
19、 include SVT - causing CHF. The rate is usually around 240 and there is minimal variation (239 - 241)Viral myocarditis can present at any age with cardiogenic shock,Cardiac Diseases - CHF,Infants presenting with CHF will have signs of 1. Respiratory distress Tachypnea, indrawing, accessory muscle us
20、e, crackles 2. Hepatomegaly 3. JVD 4. Peripheral edema CXR will show signs of CHF- usually increased perihilar markings with an enlarged heart A Cap gas is useful to determine if the infant is in shock,Cardiac Diseases- Treatment CHF,1. Oxygen 2. If BP is low - initiate inotropes - dopamine or epine
21、phrine 3. Lasix 1mg/kg iv 4. PGE 1 - 0.05 - 0.1 units/kg 5. Intubate if infant is in persistent shock 6. Arrange for echocardiogram,Cardiac Diseases - Right to Left Shunt,These infants present with cyanosis that is unresponsive to oxygen. Oxygen saturations will be lowTreatment is PGE 1 - 0.05 - 0.1
22、 units/kg/min to keep the ductus open Transfer to a centre where a permanent shunt can be inserted in the heart,Case 3,2 week old child presents with lethargy and fatigue Patient has been vomiting for 16 hours and mother is concerned about dehydration Nurse places child on the monitor,Exam,Child is
23、dehydrated Child is lethargic and had decreased cap refill Chest is clear Abdomen is soft and nontender,Concerns?,DDX Get a stat Cap gas to look at the K+ Will see low Na+ with a high K+ and a normal anion gap,Metabolic Disorders,1. Dehydration - hypernatremia, hyponatremia2. Congenital adrenal hype
24、rplasia3. Urea cycle defects4. Hypothyroidism5. Toxins - ASA, ETOH,Metabolic Disorders,1. Dehydration - Will see delayed cap refill. Decreased skin turgor, lethargy, tachycardia, dry mucous membranes Tx - fluids - 20 cc/kg of NS - then reassess,Metabolic Disorders,2. Congenital Adrenal Hyperplasia W
25、ill see ambiguous genitalia in females but males may have a hyperpigmented scrotum 1 - fluids 20 cc/kg- fluids2. - Insulin/glucose for K+ (often resolves with fluids) 3. Dexamethasone 0.2 mg/kg iv 3. Urea Cycle Defects Check the glucose - need to draw an “ammonia” level, serum ketones, Urine for red
26、ucing substances, ketones and pH, serum lactate,Case 4,2 day old presents with vomiting after feeding Patient was sent home day of birth and presents 36 hours later as he is vomiting with feeding for the last 12hours,Case 4,Child is alert and looking around Chest is clear Abdomen is mildly distended
27、 and moderately tender,DDX?,Gastrointestinal disorders,1. Gastroenteritis 2. Pyloric Stenosis 3. Intussusception 4. Appendicitis 5. Necrotizing Enterocolitis 6. Midgut volvulus 7. Duodenal atresia,Initial Management,Check BGL Start IV D10W NS at 4 cc/kg/hr Check Urine If abdomen is quite tender - su
28、rgical consult If not sure - then get Upper GI/US of abdomen Start antibiotics (cefotaxime),Gastrointestinal,1. Gastroenteritis -presents with vomiting and diarrhea Rotavirus is a common cause Tx - oral rehydration if possible - otherwise IV2. Pyloric stenosis - presents with projectile vomiting. Of
29、ten bilious. 3- 6 weeks of age Diagnosis is made by US,Gastrointestinal,3. Intussusception Usually 6 months - 18 months of age.Sx Vomiting, poor feeding, bloody stools Abdominal pain that is intermittent May see a paucity of gas in the RLQ Diagnosis - air contrast enema - also a good therapeutic man
30、euver,Gastrointestinal,4. Neonatal Appendicitis High mortality Presents with poor feeding and abdominal pain/tenderness. Abdominal distension5. Necrotizing Entercolitis Seen in premature infants who have anoxic insults at birth Bloody stools Distended abdomen Pneumatosis intestinalis on X-ray,Gastro
31、intestinal,6. Midgut volvulus Presents similar to neonatal appendicitis - pain, distension, lethargy and poor feeding High mortality as it leads to necrosis of most of the small bowel,Case 5,Patient is a 4 week old female who was born at 34 weeks (38 weeks corrected) Child was DC home after 10 days
32、due to some feeding difficulties,Exam,Child is lethargic and has poor tone Chest is clear with no accessory muscle use Abdomen is soft and nontender CVS - normal heart sounds/pulses and no murmers,Labs,Cath urine - clean CXR - nil acute CBC WBC - 12.7 HgB - 114 (slightly low) Platelets - 240,Concern
33、s?,Further Tests?,LP,WBC - 30 RBC - 12 000 Glucose 5.5 Protein -normal,Child Abuse,Can present at any age In infants - will appear as a septic infant without a fever Lethargy is usually due to intra-cerebral hemorrhages Retinal hemorrhages are diagnostic of Shaken baby syndrome Other signs of abuse
34、are often rare Diagnosis often made with LP - bloody,KEY POINTS,1. Infants have diminished reserve 2. Feeding is their most physically demanding activity. Any cardiorespiratory illness will lead to diminished feeding 3. If lethargic - check a CHEMSTRIP 4. If child is ill and no focus is found, think of child abuse,
