Hypertension and health outcomes in the PICU

Reports of the burden of hypertension in hospitalized children are emerging, but the prevalence and significance of this condition within the PICU are not well understood. The aims of this study were to validate a definition of hypertension in the PICU and assess the associations between hypertension and acute kidney injury, PICU length of stay, and mortality. Single-center retrospective study using a database of PICU discharges between July 2011 and February 2013. All children discharged from the PICU with length of stay more than 6 hours, aged 1 month through 17 years. Exclusions were traumatic brain injury, incident renal transplant, or hypotension. None. Potential definitions of hypertension utilizing combinations of standardized cutoff percentiles, durations, initiation or dose escalation of antihypertensives, and/or billing diagnosis codes for hypertension were compared using receiver operator characteristic curves against a manual medical record review. Multivariable logistic and linear regression analyses were conducted using the selected definition of hypertension to assess its independent association with acute kidney injury and PICU length of stay, respectively. A definition requiring three systolic and/or diastolic readings above standardized 99th percentiles plus 5 mm Hg over 1 day was selected (area under the curve, 0.91; sensitivity, 94%; specificity, 87%). Among the 1,215 patients in this analysis, the prevalence of hypertension was 25%. Hypertension was independently associated with acute kidney injury (odds ratio, 2.89; 95% CI, 1.64-5.09; p < 0.01) and increased PICU length of stay (1.50 d; 95% CI, 0.94-2.05; p < 0.01) in multivariable analyses. Deaths were rare-0 in the normotension group and 3 (1%) in the hypertension group-but were statistically different (p = 0.02). Hypertension is common in the PICU and is associated with worse clinical outcomes. Future studies are needed to confirm these results.