Objective: The objective of this review was to systematically review and evaluate available literature describing the effect of nicotine replacement therapy (NRT) on mortality and other outcomes in nicotine-dependent critically ill patients admitted to the intensive care unit (ICU).
Data sources: A systematic search of the following databases was performed: MEDLINE (1948-August 2011), EMBASE (1980-August 2011), Cochrane Database of Systematic Reviews, International Pharmaceutical Abstracts (1970-August 2011), Google, and Google Scholar.
Study selection: Studies that reported outcomes associated with any form of NRT in any intensive care setting were included. Studies were included regardless of design or number of participants reported. Studies published in languages other than English were excluded.
Data extraction: Data from each study were extracted using a standardized data extraction tool. Information included the study design, number of patients, classification of ICU, baseline characteristics, outcomes assessed, and overall results.
Data synthesis: Our search identified 8 studies, of which 7 met the inclusion criteria. These 7 studies were qualitatively reviewed and critically appraised for methodological quality, robustness of results, and internal and external validity. The results of similar studies and populations were compared in order to draw conclusions pertaining to specific intensive care settings.
Conclusions: We conclude that NRT should not be routinely prescribed to patients admitted to intensive care settings. With only equivocal evidence of efficacy and signals suggesting increased toxicity, we believe that its use should be limited to selected patients where the potential benefit clearly outweighs the risk. There is a need for adequately powered randomized controlled trials to confirm the benefits and risks of NRT in the ICU overall but also in its unique subpopulations.
Keywords: NRT; critical illness; nicotine; nicotine dependence; smoking; substance withdrawal syndrome.