A comparison of core and surface cooling techniques in cardiac arrest survivors

Abstract

(p < 0.001), but not in hippocampus (p = 0.23). There was no difference in TNF levels between CA6 and CA8 in any brain region. In CA6 and CA8, TNF levels were highest in the striatum (p = 0.004, p < 0.001, striatum vs. other brain regions). No regional differences could be detected in the sham group. Conclusions: While the role of neuroinflammation after CA is not yet fully elucidated, our results show a distinct regional pattern of early TNF production, with highest levels in the striatum. Inflammation in the striatum could be a novel target for antiinflammatory therapies. The source of TNF and its role remains to be defined in future experiments. Purpose of the study: In a pilot study, to evaluate the blood levels of tau protein as a prognostic marker for the neurological outcome after 6 months in patients treated with hypothermia after cardiac arrest. Materials and methods: 22 Unconscious patients resuscitated after cardiac arrest were treated with mild hypothermia (32-34 ◦C) for 26 h. Blood samples were collected at 2, 6, 12, 24, 48 and 96 h after cardiac arrest. Tau protein was analyzed. Neurological outcome was assessed with the Glasgow-Pittsburgh cerebral performance category (CPC) scale at intensive care unit (ICU) discharge and after six months. The better of the two CPC scores was used. Results: At ICU discharge 21/22 patients were alive, of whom 10 had a good (CPC 1-2) outcome. After six months, 15/22 patients were alive, of whom 14 had a good outcome. Tau protein levels were higher among those with a poor outcome at 48 and 96 h. At 96 h, tau could predict a poor outcome (CPC 3-5) with a sensitivity of 71% and a specificity of 93%. Conclusions: Tau protein is a prognostic marker for prediction of the neurological outcome after hypothermia treatment after cardiac arrest. Purpose of the study: Mild therapeutic hypothermia after out-of-hospital cardiac arrest (OHCA) is usually achieved either by surface cooling or core cooling via the patient's bloodstream. The clinical effect of surface versus core cooling is uncertain, as modern cooling devices usually have been compared to either no cooling or only basic cool- ing (cold air, icepacks, etc). We compared modern core (Coolgard ® ) and surface (Arctic Sun®) cooling devices, with a zero hypothesis of equal cooling effectiveness and patient outcomes.Materials and methods: A non-randomize single center observational study comparing 165 OHCA patients receiving either core to surface cooling. Adjusted odds ratios (OR) with 95% confidence interval were calculated in a multiple logistic regres- sion model using a forward variable selection procedure including pre- and in-hospital prognostic factors and complications.Results: There was no significant unadjusted dif- ference survival with good neurological function between core (34/75, 45%) and surface (34/90, 38%) cooled patients (p = 0.345), and time from cardiac arrest to target tempera- ture was similar with both devices (surface: 273 min, IQR 158-330; core: 270 min, IQR 190-360; p-value: 0.479). The factors found to significantly affect survival with good neurological function by the logistic regression were; lower than median response time OR 3.42 (1.37-8.53, p = 0.008), age of patient OR 0.94 (0.90-0.97, p < 0.001), an initial shockable rhythm OR 15.70 (4.05-60.94, p < 0.001), patients shivering OR 3.13 (1.12, 8.71, p = 0.029), having seizures OR 0.07 (0.02-0.28, p < 0.001) or needing insulin therapy OR 0.19 (0.07-0.49, p = 0.001) during ICU stay, and patients having a preexisting neurologi- cal disease prior to cardiac arrest OR 0.13 (0.02-0.88, p = 0.037). Adjusted OR for cooling method (Surface/core) in the model was 0.89 (0.36-0.220; p = 0.800).Conclusion: In this study surface and core cooling of OHCA patients resulted in similar time to target temper- ature and no significant difference in survival to hospital discharge with good neurological