Hypotension During Vasopressor Infusion Occurs in Predictable Clusters: A Multicenter Analysis

Abstract

AbstractRationalePublished evidence indicates that mean arterial pressure (MAP) below a goal range (hypotension) is associated with worse outcomes, though MAP management failures are common.ObjectivesCharacterize hypotension occurrences in ICUs and consider the implications for MAP management.MethodsObservational study of three retrospective and one prospective cohorts of adult ICU patients during continuous vasopressor infusion. Three cohorts of general, mixed ICU patients; one cohort of acute spinal cord injury patients. Hypotension clusters were defined wherever ≥50% of MAP measurements were hypotensive with ≥10 minutes of total hypotension. Trend analysis was performed (predicting future MAP using 14 min of preceding MAP data) to understand which hypotension clusters could likely have been predicted by clinician awareness of MAP trends.Measurements and Main ResultsIn cohorts of 155, 66, 16, and 10 subjects, respectively, hypotension occurred 12.9%, 5.5%, 21.5%, and 3.9% of the time. Hypotension occurred overwhelmingly within temporal clusters. MAP trend analysis predicted most substantial hypotension clusters (range: 66.6% to 80.0% sensitivity) prior to continuous hypotension occurring, usually before the occurrence of any hypotension at all. When MAP trend analysis predicted hypotension, positive predictive value ranged from 56% to 77% (probability of subsequent temporal cluster of hypotension or vasopressor up-titration).ConclusionsHypotension usually occurred in temporal clusters that can typically be predicted by extrapolation from trends. This implies that clinicians may be slow to identify incipient hypotension. In Cohort 4, analysis was performed in real-time, establishing a proof-of-principle for a computational tool with possible clinical utility.Statement of Clinical SignificanceThis analysis found that hypotension was relatively common in the bottom quartiles in each of four ICU cohorts, occurring in temporal clusters that could usually be predicted by trend extrapolation. This implies that clinicians may be slow to identify incipient hypotension in ICU patients. In one cohort, hypotension prediction was performed in real-time, establishing a proof-of-principle for future clinical usability.