Risk Factors for Adverse Outcome in Peripartum Hemorrhagic Shock (HS). 1032

Abstract

Rationale: Data in the perinatal animal and adult trauma patient suggest that the timing and severity of blood volume (BV) loss and rapidity and degree of BV replacement are important determinants of outcome in HS. Objective: To identify and analyze the importance of risk factors for adverse outcome. Methods: Retrospective data collection on 34 cases admitted from 1985-1994 (HSC) and 10 cases from 1988-1994 (MSH, WCH). Inclusion criteria: ≥34 wks gestation and HS at birth defined as severe pallor with reduced or absent pulses despite a HR of >100 bpm and a calculated BV loss of >25% (21 mls/kg). Exclusions: internal hemorrhage, chronic blood loss, or hemolysis. Adverse outcome included death or survival with severe neurological disability. Univariate analyses compared groups by adverse or good outcome. Results: Are expressed as median values(interquartile range). GA was 40 (37-40) wks, BW 3135 (2707-3535) g and the calculated BV loss was 48 (39-57) mls/kg. Five patients were lost to follow up and 19 of 39 (49%) had adverse outcomes: 11 died, 6 had severe CP and 2 had severe cognitive delay. Etiology of HS (cases with adverse outcome/total) included: placental abruption (5/14), fetomaternal hemorrhage (3/5), vasa praevia (4/4), umbilical cord tears (2/2), twin-to-twin transfusion (2/2), placenta praevia (1/2), tight nuchal cord (0/2), placental incision (0/2) and indeterminate (2/10). Group differences in Obstetrical factors (presence and timing of CTG abnormalities, occurrence of APH), and volume and timing of BV replacement were not statistically significant. Patients with adverse outcomes had greater blood losses of 54 vs. 44 mls/kg (p=0.03), a lower 5 minute Apgar score of 1 vs. 4 (p=0.006), greater base deficit of 21 vs. 12 mmol/l(p=0.006), and tended to have a longer interval from onset of HS to first volume replacement of 410 vs. 106 mins (p=0.19). Severe encephalopathy, seizures, DIC, myocardial ischemia, and severe renal dysfunction were strongly associated with adverse outcomes. Conclusions: Risk factors for adverse outcome included the magnitude of blood loss, severity of metabolic acidosis and depression at birth, and the presence of severe organ dysfunction. Length of time from onset of HS to first volume replacement, although not statistically significant, is likely to be a risk factor for adverse outcome.