Assessing Hemorrhage Severity with Continuous Automatic Heart-Rate-Complexity Monitoring in Swine
Abstract
Learning Objectives: Heart-rate-complexity (HRC) calculated off-line was associated with injury severity, mortality, and the performance of life-saving interventions in animal and human studies. We hypothesized that real-time automatic HRC measurements by the Aesculon monitor (Cardiotronic-Osypka Medical, USA) are associated with hemodynamic status and mortality. Methods: Spontaneously breathing consciously sedated swine were shed 65% of blood volume over 1 hour, then were randomized to 3 groups: control (C, n=7); transfusion of shed blood (TSB, n=7); or endovascular balloon occlusion of the aorta (REBOA) (Pryor Medical, Arvada, CO) for up to 60 minutes followed by TSB (n=21). Epinephrine boluses were given if mean arterial pressure (MAP) < 40 mmHg in the TSB and REBOA groups. After resuscitative interventions, animals were followed for 240 min or death. Aesculon monitor performed continuous, real-time measurements of HRC, i.e. sample entropy (SampEn) and multiscale entropy (MSE). At 30 minutes after all interventions, heart rate (HR), MAP, Lactate (Lac), and HRC metrics were assessed for their association with death using logistic regression and receiver-operating-characteristic (ROC) curve analysis. Results: All animals died in group C, 2/7 in group TSB, and 1/21 in group REBOA. SampEn and MSE decreased with hemorrhage and increased after interventions (TSB or REBOA+TSB). After resuscitative interventions, HRC metrics individually were associated with death: SampEn p=0.0002, area under the curve (AUC) =.88; MSE p=0.002, AUC=.83; both SampEn and MSE together p=0.0005, AUC=.90. Traditional vital signs were also associated with death: HR, p=0.02, AUC .72; MAP, p=0.01, AUC .85; Lac p=0.05, AUC=.69; and for all three metrics together p<0.03, AUC=0.85. When traditional and HRC variables were combined into a single model the overall AUC was .93, p=0.003.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 02, 2014
- Accession Number
- ADA621471
Entities
People
- Andriy I. Batchinsky
- Bryan Jordan
- Josè Salinas
- Leopoldo Cancio
- Michael Dubick
- Slava Belenkiy
- Timothy Park
- William Baker
Organizations
- United States Army Institute of Surgical Research