Beneficial effect of mild hypothermia and detrimental effect of deep hypothermia after cardiac arrest in dogs.
- 1 October 1992
- journal article
- research article
- Published by Wolters Kluwer Health in Stroke
- Vol. 23 (10) , 1454-1462
- https://doi.org/10.1161/01.str.23.10.1454
Abstract
Mild cerebral hypothermia (34 degrees C) induced immediately after cardiac arrest improves outcome. Deep postarrest hypothermia (15 degrees C) has not been studied. We used our dog model of normothermic ventricular fibrillation (no blood flow) of 12.5 minutes, reperfusion by brief cardiopulmonary bypass, controlled ventilation to 20 hours, and intensive care to 72 hours. Head surface cooling and bypass cooling were performed from start of reperfusion to 1 hour. Five groups of six dogs each were compared: group I, normothermic controls; group II, deep hypothermia (15 degrees C); group III, moderate hypothermia (30 degrees C); group IV, mild hypothermia (34 degrees C); and group V, mild hypothermia with head surface cooling begun during no flow. In control group I, five dogs remained comatose (overall performance category [OPC] 4) and one severely disabled (OPC 3). In group II, four dogs achieved OPC 4 and two dogs OPC 3 (NS versus group I). Compared with group I, OPCs were better in group III (p less than 0.05), group IV (p less than 0.05), and group V (p less than 0.05). Neurological deficit scores were also better in groups III, IV, and V than in groups I or II (p less than 0.05). Total brain histological damage scores were better in group III (p = 0.02), group IV (p = 0.06), and group V (p less than 0.05) than in group I. In group II, OPC and neurological deficit scores were the same and histological damage scores numerically worse than in group I and all were worse than in groups III, IV, and V (p less than 0.05). Cardiovascular complications and myocardial morphological damage in groups II and III were worse than in groups I, IV, and V (p less than 0.05). Mild or moderate cerebral hypothermia induced immediately after cardiac arrest improves cerebral outcome, more likely when initiated during arrest, whereas deep postarrest hypothermia can worsen cerebral and cardiac outcome.Keywords
This publication has 27 references indexed in Scilit:
- IMMEDUATE BUT NOT DELAYED MILD RESUSCITATIVE CERRBRAL HYPOTHERMIA IMPROVES OURCOEM AFTER CARDIAC ARRESTAnesthesiology, 1992
- RESUSCITATIVE MODERATE CEREBRAL HYPOTHERMIA AFTER EPIDURAL BRAIN COMPRESSION IN A CANINE OUTCOME MODELCritical Care Medicine, 1992
- Marked Protection by Moderate Hypothermia after Experimental Traumatic Brain InjuryJournal of Cerebral Blood Flow & Metabolism, 1991
- Mild Cerebral Hypothermia during and after Cardiac Arrest Improves Neurologic Outcome in DogsJournal of Cerebral Blood Flow & Metabolism, 1990
- Postischemic moderate hypothermia inhibits CA1 hippocampal ischemic neuronal injuryNeuroscience Letters, 1989
- Small Differences in Intraischemic Brain Temperature Critically Determine the Extent of Ischemic Neuronal InjuryJournal of Cerebral Blood Flow & Metabolism, 1987
- Cardiopulmonary bypass after prolonged cardiac arrest in dogsAnnals of Emergency Medicine, 1987
- Sympathetic nervous system “switch off” with severe hypothermiaCritical Care Medicine, 1983
- TEMPERATURE GRADIENTS DURING HYPOTHERMIAAnnals of the New York Academy of Sciences, 1959
- A CAUSE OF THE THROMBOCYTOPENIA AND LEUKOPENIA THAT OCCUR IN DOGS DURING DEEP HYPOTHERMIAJournal of Clinical Investigation, 1958