Methods: Retrospective analysis of all patients with in-hospital cardiac arrest and return of spontaneous circulation (ROSC) in the ICU of the cardiologic department of the University Hospital of Halle (Saale) between 1999 and 2009. Results: During the observation period, 169 patients with in-hospital cardiac arrest and information regarding temperature measurements were treated. Invasive therapeutic temperature management (TTM+) was applied in 64 patients (37.9%), while 105 patients (62.1%) underwent no therapeutic temperature management (TTM−). TTM+ and TTM− showed no relevant differences regarding patient age (TTM+: 67.6 ± 12.6 years; TTM−: 69.8 ± 12.6 years; p = 0.257), comorbidities and the initial rhythm; however, there were more men in the TTM+ group (76.6% vs. 58.1%; p = 0.015). All patients had been intubated. Time until ROSC in TTM+ was significantly longer (25.9 ± 25.8 min vs. 15.0 ± 12.4 min; p < 0.005). TTM+ resulted in a lower 30-day survival and an unfavourable neurologic outcome (Glasgow outcome scale I or II: 75% TTM+ vs. 55.2% TTM−). This negative effect persisted after adjustment for age of the patients, but not after adjustment for age and duration of reanimation (nonadjusted odds ratio for adverse neurologic outcome under TTM+: 0.411 (p = 0.011); odds ratio after adjusting for age: 0.361 (p = 0.09); odds ratio after adjusting for age and duration of the reanimation: 0.505 (p = 0.121)).