Comparison of Compensatory Reserve Index Before and After Analgesia
Abstract
Prehospital assessment of cardiovascular stability during hemorrhage is unpredictable because standard vital signs do not predict cardiovascular shock until it is too late for the medic to respond with a life‐saving intervention. In an effort to improve survival from hemorrhage, a machine learning algorithm has been developed as an early predictor of cardiovascular shock. The algorithm is able to detect reductions in central blood volume during blood loss, and assess the individual's capacity to compensate for blood loss by calculating beat‐ to‐beat compensatory reserve index (CRI) from a finger photoplethysmography waveform. CRI=100 represents normovolemia and CRI=0 represents hypovolemia at the point of cardiovascular decompensation. The algorithm has been validated in blood loss studies in animals and humans; however these studies were conducted in the absence of other confounding factors associated with blood loss such as trauma and pain. The current study was designed to determine if pain, in the absence of trauma, affects CRI by comparing CRI before and after epidural anesthesia to provide analgesia during childbirth. The purpose of this study was to test the hypothesis that pain or analgesia does not affect CRI.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Apr 01, 2017
- Source ID
- 10.1096/fasebj.31.1_supplement.1029.1
Entities
People
- Carmen Hinojosa‐laborde
- Corinne D. Nawn
- Gary W. Muniz
- Jessie Renee D. Fernandez
- John T. Hardy
- Kathy B. Porter
- Rebecca K. Burns
- Thuan H. Le
- Victor A Convertino
Organizations
- San Antonio Military Medical Center
- United States Army Institute of Surgical Research
- United States Army Medical Research and Development Command