Context: During surgery, many patients become hypothermic. Health complications resulting from hypothermia lead to longer hospital stays and increased healthcare costs. Objective: To identify in empirical research results the active warming systems that proved to be most effective in the pre and intraoperative periods to prevent perioperative hypothermia. Methodology: The search was performed using the following keywords: Hypothermia, perioperative nursing, anaesthesia and rewarming. Publications from the last five years (2007-2012), with full text, and written in English, Spanish or Portuguese were included. Articles on pregnant women, neurocritical patients, induced hypothermia and the variables affecting hypothermia were excluded. Results: A total of 30 articles were obtained, seven of which were selected for analysis. Conclusion: Active warming methods are effective measures for the prevention of hypothermia; the combination of warming methods is more effective than an isolated use; and, finally, the forced-air system and circulating water garments proved to be the most effective active warming methods.