A. Somaney1,2, G. Harea1, D. Wendorff1, J. Callahan1, H. Kill1,2, M. Angela1,2, G. Haden1,2, M. Batchinsky1, B. Beely1, R. Teryn1,2, J. Weidling3, M. Keating3, E. Botvinick3,4, A. Batchinsky1,2 1Autonomous Reanimation And Evacuation Research Institute and Innovation Center, San Antonio, TX, USA 2Department of Translational Medicine, University Of The Incarnate Word School Of Osteopathic Medicine, San Antonio, TX, USA 3Beckman Laser Institute, University Of California Irvine, Irvine, CA, USA 4Edwards Lifesciences Center for Advanced Cardiovascular Technology, University Of California Irvine, Irvine, CA, USA
Introduction: Lactate (LAC) accumulates in the blood under conditions like tissue hypoperfusion, sepsis, and trauma, serving as a biomarker for evaluating the severity of these pathologic states. LAC quantification and expediency of clearance from blood, offer prognostic value, facilitating clinical decision-making and guiding therapeutic interventions. This study evaluated a new wearable Continuous Lactate Monitor (CLM) currently undergoing preclinical validation in porcine models of combat-relevant trauma at our Institute. The CLM comprises an optical probe inserted via a needle under the skin, an optical detector attached to the skin surface above the probe, and a data acquisition and control system. We evaluated CLM performance in a model of severe combat-relevant trauma in swine. Purpose: Assess the feasibility, reliability and accuracy of CLM vs. direct measurement of LAC in blood by arterial blood gas analysis. Hypothesis: CLM LAC values significantly correlate with arterial LAC during multi-day testing in a swine undergoing large swings in resuscitation.
Methods: Female Yorkshire swine (50-60 kg, n=8) were anesthetized, mechanically ventilated, and received bilateral pulmonary contusion (PC) using a captive bolt device with or without traumatic brain injury (TBI) and severe hemorrhage (n=8 PC, n=2 TBI; n=3 hemorrhage) treated with immediate application of veno-venous extracorporeal life support (ECLS) (HLS 7.0 [Getinge/Maquet, Rastatt, Germany] or XLung [Fresenius Medical Care, Bad Homburg, Germany]) via 23 Fr. dual-lumen jugular cannulation. Two CLMs were placed on the skin in the lower abdomen. CLM data was compared to blood LAC measured by arterial blood gas (GEM Premier 4000, Werfen, Bedford, MA). Pearson Correlation Coefficient was calculated to compare the two measurements for every paired point CLM and ABG data. Bland-Altman analysis was performed to assess the agreement of CLM data to blood LAC measurements before and after injury up to 72 hours yielding 196 paired measurements.
Results: CLM showed significant correlation with ABG LAC, Pearson correlation coefficient = 0.78, p < 0.0001. Bland-Altman showed good agreement with loss of agreement at LAC values above 13 mmol/L.
Conclusion: CLM significantly correlated with ABG LAC numbers in the 0-13 mM range of values. Utilization of CLM may significantly enhance real-time monitoring and management of critical patients with promising early decision-making implications in trauma.