OBJECTIVES: Hypothermia of 32 degrees C-34 degrees C induced after resuscitation from cardiac arrest improves neurologic recovery, but the optimal depth of cooling is unknown. Using a rat model, the authors tested the hypothesis that cooling to 35 degrees C between hours 1 and 24 after resuscitation would improve neurologic outcome as much as cooling to 33 degrees C. METHODS: Halothane-anesthetized rats (n = 38) underwent 8 minutes of asphyxial cardiac arrest and resuscitation. Cranial temperature was maintained at 37 degrees C before, during, and after arrest. Between one and 24 hours after resuscitation, cranial temperature was maintained at 33 degrees C, 35 degrees C, or 37 degrees C using computer-controlled cooling fans and heating lamps. Neurologic scores were measured daily, and rats were killed at 14 days for histologic analysis. Neurons per high-powered field were counted in the CA1 region of the anterior hippocampus using neuronal nuclear antigen staining. RESULTS: After 14 days, 12 of 12 rats (100%) cooled to 33 degrees C, 11 of 12 rats (92%) cooled to 35 degrees C, and ten of 14 rats (71%) cooled to 37 degrees C survived, with hazard of death greater in the rats cooled to 37 degrees C than in the combined hypothermia groups. Neurologic scores were worse in the rats cooled to 37 degrees C than in the hypothermia groups on days 1, 2, and 3. Numbers of surviving neurons were similar between the groups cooled to 33 degrees C and 35 degrees C and were higher than in the group cooled to 37 degrees C. CONCLUSIONS: These data illustrate that hypothermia of 35 degrees C or 33 degrees C over the first day of recovery improves neurologic scores and neuronal survival after cardiac arrest in rats. The benefit of induced hypothermia of 35 degrees C appears to be similar to the benefit of 33 degrees C.
OBJECTIVES:Hypothermia of 32 degrees C-34 degrees C induced after resuscitation from cardiac arrest improves neurologic recovery, but the optimal depth of cooling is unknown. Using a rat model, the authors tested the hypothesis that cooling to 35 degrees C between hours 1 and 24 after resuscitation would improve neurologic outcome as much as cooling to 33 degrees C. METHODS:Halothane-anesthetized rats (n = 38) underwent 8 minutes of asphyxial cardiac arrest and resuscitation. Cranial temperature was maintained at 37 degrees C before, during, and after arrest. Between one and 24 hours after resuscitation, cranial temperature was maintained at 33 degrees C, 35 degrees C, or 37 degrees C using computer-controlled cooling fans and heating lamps. Neurologic scores were measured daily, and rats were killed at 14 days for histologic analysis. Neurons per high-powered field were counted in the CA1 region of the anterior hippocampus using neuronal nuclear antigen staining. RESULTS: After 14 days, 12 of 12 rats (100%) cooled to 33 degrees C, 11 of 12 rats (92%) cooled to 35 degrees C, and ten of 14 rats (71%) cooled to 37 degrees C survived, with hazard of death greater in the rats cooled to 37 degrees C than in the combined hypothermia groups. Neurologic scores were worse in the rats cooled to 37 degrees C than in the hypothermia groups on days 1, 2, and 3. Numbers of surviving neurons were similar between the groups cooled to 33 degrees C and 35 degrees C and were higher than in the group cooled to 37 degrees C. CONCLUSIONS: These data illustrate that hypothermia of 35 degrees C or 33 degrees C over the first day of recovery improves neurologic scores and neuronal survival after cardiac arrest in rats. The benefit of induced hypothermia of 35 degrees C appears to be similar to the benefit of 33 degrees C.
Authors: Patrick J Coppler; Keith A Marill; David O Okonkwo; Lori A Shutter; Cameron Dezfulian; Jon C Rittenberger; Clifton W Callaway; Jonathan Elmer Journal: Ther Hypothermia Temp Manag Date: 2016-06-01 Impact factor: 1.286
Authors: Cindy H Hsu; Bryce E Haac; Mack Drake; Andrew C Bernard; Alberto Aiolfi; Kenji Inaba; Holly E Hinson; Chinar Agarwal; Joseph Galante; Emily M Tibbits; Nicholas J Johnson; David Carlbom; Mina F Mirhoseini; Mayur B Patel; Karen R OʼBosky; Christian Chan; Pascal O Udekwu; Megan Farrell; Jeffrey L Wild; Katelyn A Young; Daniel C Cullinane; Deborah J Gojmerac; Alexandra Weissman; Clifton Callaway; Sarah M Perman; Mariana Guerrero; Imoigele P Aisiku; Raghu R Seethala; Ivan N Co; Debbie Y Madhok; Bryan Darger; Dennis Y Kim; Lara Spence; Thomas M Scalea; Deborah M Stein Journal: J Trauma Acute Care Surg Date: 2018-07 Impact factor: 3.313
Authors: Ericka L Fink; Robert S B Clark; Patrick M Kochanek; Michael J Bell; R Scott Watson Journal: Pediatr Crit Care Med Date: 2010-01 Impact factor: 3.624
Authors: Fei Han; Manuel Boller; Wenhui Guo; Raina M Merchant; Joshua W Lampe; Thomas M Smith; Lance B Becker Journal: Resuscitation Date: 2009-11-18 Impact factor: 5.262
Authors: Laurence M Katz; Jonathan E Frank; Gerald McGwin; Alex Finch; Christopher J Gordon Journal: Ther Hypothermia Temp Manag Date: 2012-06 Impact factor: 1.286
Authors: Clifton W Callaway; Ramiro Ramos; Eric S Logue; Amy E Betz; Matthew Wheeler; Melissa J Repine Journal: Neurosci Lett Date: 2008-08-13 Impact factor: 3.046