Return of consciousness during ongoing cardiopulmonary resuscitation: A systematic review

Abstract

Objectives: Cardio-pulmonary resuscitation (CPR) may generate sufficient cerebral perfusion pressure to make the patient conscious. The incidence and management of this phenomenon are not well described. This systematic review aims to identifying cases where CPR-induced consciousness is mentioned in the literature and explore its management options. Methods: The databases Medline, PubMed, EMBASE, Cinahl and the Cochrane Library were searched from their commencement to the 8th July 2014. We also searched Google (scholar) for grey literature. We combined MeSH terms and text words for consciousness and CPR, and included studies of all types. Results: The search yielded 1997 unique records, of which 50 abstracts were reviewed. Nine reports, describing 10 patients, were relevant. Six of the patients had CPR performed by mechanical devices, three of these patients were sedated. Four patients arrested in the out-of-hospital setting and six arrested in hospital. There were four survivors. Varying levels of consciousness were described in all reports, including purposeful arm movements, verbal communication, and resuscitation interference. Management strategies directed at consciousness were offered to six patients and included both physical and chemical restraints. Conclusion: CPR-induced consciousness was infrequently reported in the medical literature, and varied in management. Given the increasing use of mechanical CPR, guidelines to identify and manage consciousness during CPR are required.