Introduction: Although common, the clinical relevance of changes in blood pressure (BP) in neonates with late-onset bloodstream infection (LBSI) are not well established. Our objective was to investigate the association between systolic (SBP), diastolic (DBP) and mean blood pressures (MBP) and organ dysfunction (ODF) and mortality in premature neonates with LBSI.
Methods: This retrospective study, conducted over 6 years, included neonates 72 hours of age, positive for a non-coagulase-negative staphylococcus organism. Lowest recorded non-invasive BP between 24-48 hours before (baseline BP), and for each 12-hour period after LBSI-onset were compared between: a) Infants with and without ODF [defined as any of the following: renal dysfunction (creatinine ≥100mmol/L or urine output ≤1ml/kg/h for 8 hours), base deficit ≥8mEq/L, severe hypoxemia (invasive ventilation with FiO2 1.0 for ≥2 hours) or cardiac arrest]; and b) those who died ≤7 days after LBSI vs. survived. Absolute BPs and change from baseline were compared using mixed effect model with repeat measures, adjusted for relevant variables. Area under the curve (AUC) were calculated for ODF (using pre-ODF BPs) and death (using first 12 hours post-LBSI-onset BPs).
Results: Of the 147 neonates included, 70 (48%) developed ODF after LBSI (Table 1). Post-LBSI BPs were lower for ODF neonates vs. non-ODF (Figure1, Table 2), and those who died vs. survived, with maximum drop seen in SBP (Table 3). The AUCs for SBP, DBP and MBP for predicting ODF and death were 0.63, 0.65, 0.63, and 0.83, 0.78, 0.81 respectively (Figure 2).
Conclusion: A drop in BP after LBSI is associated with ODF and mortality, while low SBP may identify neonates at highest risk of mortality from LBSI, early in illness.
Michelle Baczynski– Respiratory Therapy Practice Resource, Mount Sinai Hospital
Ashraf Kharrat– Neonatologist, Mount Sinai Hospital
Philip Ye– Statistician, Mount Sinai Hospital
Dany Weisz– Neonatologist, Sunnybrook Health Sciences
Amish Jain– Neonatologist, Mount Sinai Hospital