Hypertension and Health Outcomes in the PICU

Abstract

Objectives Reports of the burden of hypertension in hospitalized children are emerging, but the prevalence and significance of this condition within the pediatric intensive care unit (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 (AKI), PICU length of stay (LOS), and mortality. Design and Setting Single center retrospective study using a database of PICU discharges between July 2011 and February 2013. Patients All children discharged from the PICU with LOS > 6 hours, aged 1 month through 17 years. Exclusions were traumatic brain injury, incident renal transplant, or hypotension. Measurements and Main Results 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 AKI and PICU LOS, respectively. A definition requiring 3 systolic and/or diastolic readings above standardized 99th percentiles plus 5 mmHg 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 AKI (OR 2.89, 95% CI 1.64–5.09, P<0.01) and increased PICU LOS (1.50 days, 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). Conclusions Hypertension is common in the PICU and is associated with worse clinical outcomes. Future studies are needed to confirm these results.

Acute Kidney Injury In Children Admitted In Pediatric Intensive Care Unit

“…Hypotension is a common cause of renal hypoperfusion leading to acute tubular necrosis. The diagnosis is suspected when AKI develops after a hypotensive event, severe sepsis, or drug exposure and is distinguished from prerenal AKI by laboratory testing and response to volume expansion (28). Interestingly; it was observed that hypertension in PICU children was associated with AKI (29).…”

Validation of the KDIGO acute kidney injury criteria in a pediatric critical care population

“…That is to say if the SCr rose from 0.1 to 0.2 mg/dL or from 0.1 to 0.4 mg/dL each did not qualify as AKI (SCr was not above 0.5 mg/dL), but if the SCr rose from 0.4 to 0.6 mg/dL or from 0.3 to 0.6 mg/dL this did qualify as AKI (SCr was above 0.5 mg/dL). This was utilized to account for the precision of our assay locally and has been utilized successfully in previous reports [18][19][20] to prevent a bias toward classifying AKI as present in young infants [21]. A modified Jaffe reaction is utilized for SCr measurement at the University of Michigan.…”

Case–control study exploring the short-term association of bronchiolitis with high blood pressure and hypertension in hospitalized children

“…The more conservative estimates come from studies where the diagnosis was established retrospectively, based on a billing code diagnosis of HTN at discharge; the more liberal estimates are from studies using single emergency room admission BP measurements [ 13 , 14 ]. Studies suggest that critical illness is a risk factor for acutely elevated BP; Ehrmann et al [ 15 ] found the prevalence of HTN to be 25% among pediatric ICU patients when defining HTN as at least three SBP and/or DBP readings above the 99th percentile over 1 day. Most importantly, this study correlated HTN using this definition to clinical outcomes such as increased odds of acute kidney injury and increased length of stay [ 15 ].…”

“…Studies suggest that critical illness is a risk factor for acutely elevated BP; Ehrmann et al [ 15 ] found the prevalence of HTN to be 25% among pediatric ICU patients when defining HTN as at least three SBP and/or DBP readings above the 99th percentile over 1 day. Most importantly, this study correlated HTN using this definition to clinical outcomes such as increased odds of acute kidney injury and increased length of stay [ 15 ].…”