Cognitive dysfunction and health-related quality of life after a cardiac arrest and therapeutic hypothermia J. TORGERSEN 1,2 , K. STRAND 3 , T. W. BJELLAND 4 ,P.KLEPSTAD 4,5 , R.KVA ˚ LE 1 , E. SØREIDE 3 , T. WENTZEL-LARSEN 6 and H. FLAATTEN 1,2 1 Department of Anaesthesiology and Intensive Care Medicine, Haukeland University Hospital, Bergen, Norway, 2 Section for Anaesthesiology and Intensive Care, Department of Surgical Sciences, University of Bergen, Bergen, Norway, 3 Department of Anaesthesiology and Intensive Care Medicine, Stavanger University Hospital, Stavanger, Norway, 4 Department of Circulation and Medical Imaging, Medical Faculty, Norwegian University of Science and Technology, Trondheim, Norway, 5 Department of Intensive Care Medicine, St Olav’s University Hospital, Trondheim, Norway and 6 Centre for Clinical Research, Haukeland University Hospital, Bergen, Norway Background: Evidence-based treatment protocols includ- ing therapeutic hypothermia have increased hospital survival to over 50% in unconscious out-of-hospital cardiac arrest survivors. In this study we estimated the incidence of cognitive dysfunctions in a group of cardiac arrest survivors with a high functional outcome treated with therapeutic hypothermia. Secondarily, we assessed the cardiac arrest group’s level of cognitive performance in each tested cognitive domain and investigated the relationship between cognitive function and age, time since cardiac arrest and health-related quality of life (HRQOL). Methods: We included 26 patients 13–28 months after a cardiac arrest. All patients were scored using the Cerebral Performance Category scale (CPC) and Mini-Mental State Examination (MMSE). Twenty-five of the patients were tested for cognitive function using the Cambridge Neu- ropsychological Test Automated Battery (CANTAB). These patients were tested using four cognitive tests: Motor Screening Test, Delayed Matching to Sample, Stockings of Cambridge and Paired Associate Learning from CANTAB. All patients filled in the Short Form-36 for the assessment of HRQOL. Results: Thirteen of 25 (52%) patients were classified as having a cognitive dysfunction. Compared with the refer- ence population, there was no difference in the perfor- mance in motor function and delayed memory but there were significant differences in executive function and episodic memory. We found no associations between cog- nitive function and age, time since cardiac arrest or HRQOL. Conclusion: Half of the patients had a cognitive dysfunc- tion with reduced performance on executive function and episodic memory, indicating frontal and temporal lobe affection, respectively. Reduced performance did not affect HRQOL. Accepted for publication 18 January 2010 r 2010 The Authors Journal compilation r 2010 The Acta Anaesthesiologica Scandinavica Foundation P ATIENTS admitted to hospital after successful resuscitation from an out-of-hospital cardiac arrest (OHCA) have reported survival rates to discharge between 25% and 56%. 1–3 Therapeutic hypothermia (TH), percutaneous coronar interven- tion and strict regulation of vital and biochemical parameters, such as blood pressure and serum glucose, have become important parts of modern post-resuscitation intensive care. 1,3–5 The func- tional outcome in patients discharged alive from hospital varies from severe neurological and neu- ropsychological disability caused by brain damage to an outcome equal to the pre-arrest function level. 6,7 Studies have shown that 75–100% of the survivors have a good functional outcome. 1–3 TH is a part of acute-phase treatment after OHCA. 8–10 During TH, the body temperature is reduced to 33–34 1C for 24–48 h. This reduces the metabolism and oxygen consumption and is be- lieved to have a protective effect on brain cells. Cerebral Performance Category (CPC) is used to categorize the functional outcome after cerebral damage. 11 There is increasing evidence that TH has contributed to the increased survival rate and improved overall neurological outcome in OHCA patients when measured with CPC. 12,13 There is, however, still no evidence that TH reduces the risk of cognitive dysfunctions. Studies on cardiac arrest survivors treated with TH suggest that a mild cognitive decline is still common in this group, 721 Acta Anaesthesiol Scand 2010; 54: 721–728 Printed in Singapore. All rights reserved r 2010 The Authors Journal compilation r 2010 The Acta Anaesthesiologica Scandinavica Foundation ACTA ANAESTHESIOLOGICA SCANDINAVICA doi: 10.1111/j.1399-6576.2010.02219.x