Unmasking the Confounder: The Inherent Physiologic Variability of Swine During an Automated Experimental Model of Ischemia-Reperfusion Injury.
Am Surg
; 88(8): 1838-1844, 2022 Aug.
Article
in En
| MEDLINE
| ID: mdl-35392677
ABSTRACT
BACKGROUND:
We sought to determine the magnitude of the inherent inter-animal physiologic variability by automating a porcine Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) protocol to minimize external influences that might alter physiology and confound experimental results.METHODS:
Swine (n = 42) underwent a controlled 30% blood volume hemorrhage followed by 30 minutes of REBOA (ie, ischemic phase). The animals were weaned from REBOA autonomously over 15 minutes, beginning the reperfusion phase, while continuing to provide partial flow balloon support to maintain a target proximal mean arterial pressure (pMAP) of 65 mmHg. Simultaneously, shed blood was re-transfused as part of the resuscitation efforts. Physiologic data were continuously recorded, and serum samples were serially collected. Baseline characteristics, variance in vital signs, and 8-isoprostane levels were quantified during hemorrhage, REBOA, and reperfusion phases.RESULTS:
There was no significant difference in baseline physiology across animals (P > .05). Hemodynamic variability was highest for pMAP during the ischemic phase (P = .001) and for distal mean arterial pressure (dMAP) during the weaning/reperfusion phase (P = .001). The latter finding indicated the variable physiologic response to ischemia-reperfusion injury, as the automated balloon support required by each animal to maintain pMAP was highly variable. Circulating 8-isoprostane variance was significantly higher following the start of reperfusion compared to baseline levels (P = .001).DISCUSSION:
Despite subjecting animals to a highly consistent ischemia-reperfusion injury through automation, we noted significant variability in the hemodynamic and biochemical response. These findings illustrate the inherent physiologic variability and potential limitations of porcine large animal models for the study of shock.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Shock, Hemorrhagic
/
Reperfusion Injury
/
Balloon Occlusion
/
Endovascular Procedures
Type of study:
Prognostic_studies
Limits:
Animals
Language:
En
Journal:
Am Surg
Year:
2022
Document type:
Article
Affiliation country:
Estados Unidos