Neonatal Sepsis NICU Night Team Curriculum

Sepsis: Objectives Define Sepsis Review common pathogens causing sepsis in a neonate Review clinical findings Review the initial work up of an infant suspected of having sepsis Review initial management of neonatal sepsis

While on call in the NICU… The nurse pages: A 6 hr-old 36 wk female has developed apenic and bradycaridic episodes Infant was born to G1P1 mother via NSVD who developed a temperature of 39.1 shortly before the fetus was delivered. Maternal serologies were negative except for a GBS positive urine culture at 20 weeks GA. Mom received 1 dose of antibiotics secondary to a precipitous delivery. Pregnancy was otherwise unremarkable. Infant has been in NICU x 6 hours receiving Ampicillin and Gentamicin

Physical exam T:36.5C, P:170, RR:62, MAP:33, SpO2: 92% on 1LNC Gen/Head: AFOSF, atraumatic CV: Tachycardic rate with observed episodes of bradycardia during exam with lowest observed heart rate of 85, NL S1/S2, No murmur. Cap refill ~3 sec Pulm: Tachypnic rate, subcostal retractions observed. No crackles, no rales/rhonchi. Abd: Soft, non-tender, non-distended. Skin: No rash, petechiae or purpura.

Neonatal Sepsis Definition: –A clinical syndrome in an infant 28 days of life or less, manifested by systemic signs of infection and/or isolation of a bacterial pathogen from the blood stream (Edwards, 2004) Further Classification: –Early-onset: Onset of symptoms in first 6 days of life –Late-onset: Onset of symptoms after first week of life

Pathogenesis Early-onset sepsis: –Vertical transmission Contaminated amniotic fluid Vaginal bacteria –Increased risk with maternal chorioaminitis Late-onset sepsis: –Vertical transmission causing neonatal colonization that later results in infection –Horizontal Transmission Environmental exposures Introduction from instrumentation –Increased risk with any interruption of fetal immune system

Clinical Findings Subtle changes in baseline behavior and feeding patterns Fetal distress during delivery Most common findings: –Hyperthermia –Respiratory distress –Poor feeding –Vomiting –Jaundice –Hepatomegaly –Lethargy Less frequently seen: –Cyanosis –Hypothermia –Irritability –Apnea –Abdominal Distension

Back to the patient… You are at the bedside and the patient is continuing to have bradycardic episodes throughout the exam What are your first steps in evaluation? How would you treat this patient?

Evaluation Culture all body fluids –Blood Positive blood culture is the only method of truly diagnosis neonatal sepsis –CSF –Urine Not necessary in infants <6 days as UTIs are rarely the source of sepsis –Any other sites of infection (pustules, purulent eye drainage) CBC –Increased suspicion with: WBC count <5000/microL Absolute neutropenia Elevation of immature white blood cells when compared to PMNs (I:T ratio) (Newman, 2010) CRP –Value of > 1.0 mg/dL has a 90% sensitivity of detecting sepsis (Pourcyrous, 2003) but is not specific and increases in response to many other factors (maternal fever, hypoxia, IVH) –Most value when trend is followed over time Chest x-ray with signs of respiratory distress

Management Antibiotic Therapy –Empiric coverage for common pathogens Early-onset –Ampicillin and Gentamicin Late-onset –Ampicillin and Gentamicin –Vancomycin subsituted for Ampicillin for those with possible CONS or MRSA infection –Clindamycin for those with suspected anaerobic infections –Narrow coverage after organism is identified –Duration depends fluid from which organism was isolated Supportive Care –Fluid resuscitation Crystalloid Colloid –Pressor support in those who do not respond to fluid –Electrolyte replacement –Ventillatory support when necessary

References Edwards MS, Baker CJ. Sepsis in the Newborn. Krugman's Infectious Diseases of Children, 11th, Gershon AA, Hotez PJ, Katz SL (Eds), Mosby, Philadelphia p.545. Newman TB, Puopolo KM, Wi S, Draper D, Escobar GJ. Interpreting complete blood counts soon after birth in newborns at risk for sepsis. Pediatrics. 2010;126(5):903. Pourcyrous M, Bada HS, Korones SB, Baselski V, Wong SP. Significance of serial C-reactive protein responses in neonatal infection and other disorders. Pediatrics. 1993;92(3):431.