Warming Injections Lowers Pain
"Warming an injection is a cost-free step that emergency physicians can take to reduce pain from a shot," said Anna Taddio, MD, of the University of Toronto in Canada, and lead author of the study: Systematic Review and Meta-Analysis of the Effect of Warming Local Anesthetics on Injection Pain.
"Patients often dread the sight of a needle, but doing something as simple as warming the injection to body temperature can make a painful part of an emergency department visit more tolerable," Taddio said.
Taddio reviewed 18 previous studies involving 831 patients, and found that warming injections consistently produced a "clinically meaningful reduction in pain" regardless of whether the anesthetic had been buffered or not, regardless of whether the shot was administered subcutaneously or intradermally and regardless of whether the amount being injected was small or large.
Injections were warmed using controlled water baths, incubators, fluid warmers, baby food warmers, a warming tray and a syringe warmer. Some emergency physicians warm injections in their hands prior to administering them, the research found.
"Future research should examine the effects of warming local anesthetics for dental procedures and for procedures specifically involving children," Taddio said. "This is an area where a small change may make a big difference for a patient."