Shivering is a common side effect of targeted temperature modulation and general anesthesia. Antishivering strategies often employ a stepwise approach involving both pharmacological and physical interventions. However, approaches to treat shivering are often empiric and vary widely across care environments. We evaluated the quality of published antishivering protocols and guidelines with respect to methodological rigor, reliability, and consistency of recommendations.
Using 4 medical databases, we identified 4027 publications that addressed shivering therapy, and excluded 3354 due to lack of relevance. After applying predefined eligibility criteria with respect to minimal protocol standards, 18 protocols/guidelines remained. Each was assessed using a modified Appraisal of Guidelines for Research and Evaluation II (mAGREE II) instrument containing 23 quality items within 6 domains (maximal score 23). Among 18 protocols/guidelines, only 3 incorporated systematically reviewed recommendations, whereas 15 merely targeted practice standardization. Fifteen of 18 protocols/guidelines addressed shivering during therapeutic cooling in which skin counterwarming and meperidine were most commonly cited. However, their mAGREE II scores were within the lowest tertile (1 to 7 points) and the median for all 18 protocols was 5. The quality domains most commonly absent were stakeholder involvement, rigor of development, and editorial independence. Three of 18 protocols/guidelines addressed postanesthetic antishivering. Of these, the American Society of Anesthesiologists guidelines recommending forced-air warming and meperidine received the highest mAGREE II score (14 points), whereas the remaining 2 recommendations had low scores (<5 points).
Current published antishivering protocols/guidelines lack methodological rigor, reliability, and strength, and even the highest scoring of the 18 protocols/guidelines fulfilled only 60% of quality items. To be consistent with evidence-based protocol/guideline development processes, future antishivering treatment algorithms should increase methodological rigor and transparency.