Elevated central venous pressure is associated with increased mortality in pediatric septic shock patients

Abstract

Background: Central venous pressure (CVP) is an important factor affecting capillary blood flow, and it is associated with poor outcomes in adult septic shock patients. However, whether a similar association exists in pediatric patients remains unclear. Methods: We retrospectively analyzed data from patients admitted to our pediatric intensive care unit (PICU) between February 2009 and July 2015. Patients were divided into two groups-survivors and nonsurvivors-according to 28-day mortality. The associations between (a) mortality and CVP at 6, 24, 48, and 72h after initiating treatment for established septic shock was analyzed and (b) initial serum lactic acid levels and 6-h CVP. Results: Two hundred twenty-six patients were included in this study, and the mortality rate was 29.6% (67 deaths, nonsurvivor group). Initial serum lactic acid levels, Pediatric Risk of Mortality (PRISM) III score, and Vasoactive-Inotropic Score (VIS) within 24h after PICU admission were significantly higher in the nonsurvivors than in survivors (1.3 [0.9, 2.4] vs. 3.9 [1.6, 8.0] mmol/l, 11.0 [7.0, 15.0] vs. 17.0 [10.0, 21.5], 12.0 [7.0, 25.0] vs. 22.5 [8.0, 55.0], respectively with p-values <0.001, <0.001, and 0.009, respectively). In addition, compared to survivors, a greater percentage of nonsurvivors required mechanical ventilation (92.5% vs. 51.6%, p< 0.001) and showed a greater extent of fluid overload at 48h after admission (3.9% vs. 1.9%, p=0.006), along with higher 6-h CVP (10.0 [7.0, 16.0] vs. 8.0 [5.0, 11.0] mmHg, p< 0.001). Patient survival according to levels of CVP (CVP<8mmHg, CVP 8-12mmHg, or CVP>12mmHg) showed that the CVP>12-mmHg group had significantly greater mortality rates (50.0%, p=0.002) than the other groups (21.3% and 27.5%). Furthermore, multivariate analysis identified significant associations of CVP>12mmHg, serum lactic acid levels, and the need for mechanical ventilation with mortality (OR: 2.74, 1.30, and 12.51, respectively; 95% CI: 1.11-6.72, 1.12-1.50, and 4.12-37.96, respectively). Conclusions: Elevated CVP is an independent risk factor for mortality in pediatric septic shock patients.