Admission plasma vasopressin levels in children with meningococcal septic shock.

OBJECTIVE: Vasopressin (AVP) response has been reported to be inappropriately low in adult established septic shock. We studied admission AVP levels in children with meningococcal septic shock (MSS). PATIENTS AND METHODS: All children with meningococcal infection admitted to our PICU between May 2001 and August 2002 were classified as MSS (persistent hypotension despite fluid therapy, with perfusion abnormalities and the need for vasoactive drug infusion for at least 24 h or until death), or meningococal infection without shock (fever and purpura, with or without meningitis). Blood samples were collected at admission and AVP levels were subsequently determined using Nichols Institute Diagnostics vasopressin assay. Eighteen of 19 children with MSS (7 deaths) and 15 without shock (no death) were included.
RESULTS: In children with MSS median admission AVP level was 41.6 pg/ml (1.4-498.9) and in those without 3.3 pg/ml (1.6-63.8). In children with MSS the AVP level was not correlated with duration of shock and fluid expansion prior to AVP sampling, or with age-adjusted blood pressure and natremia at the time of blood sampling. AVP levels were higher in nonsurvivors, but not significantly so. Only one nonsurvivor had an admission AVP level below 30 pg/ml.
CONCLUSIONS: In our children with established MSS who died the admission AVP level Delta were not inappropriately low. Further studies including serial AVP level assessments are needed before concluding that AVP administration is of little interest in children with MSS.