Study Question: Can active local warming of the lower abdomen and back reduce the symptoms of renal colic?

Setting: Emergency department

Study Design: Randomized controlled trial (single-blinded)

Synopsis: Acute renal colic is one of the most unbearable forms of pain—the only time men can have an idea of how labor pains feel. An effective form of pain relief that can be administered before reaching the hospital would be welcomed, especially by patients with recurrent stones. Investigators enrolled 100 patients, 19 to 40 years of age, with a history of kidney stones who presented to the emergency department with intense pain consistent with renal colic.

Participants were covered on the lower abdomen and lower back with an electric heating blanket and then randomly assigned (concealed allocation) to an active heating (blanket turned on) or a passive warming (no electricity) group. Pain, anxiety, and nausea were measured using visual analog scales and were assessed by persons blinded to treatment group assignment.

Seventy-four of the original 100 patients eventually were diagnosed with true urolithiasis and only these participants were included in the final data analysis. Thus, we cannot be certain that the results would be similar for all patients presenting with renalcolic–type pain. All patients in the active warming group reported a decrease in pain of 50 percent or more compared with almost no change in pain scores reported by patients in the passive warming group (P < .01). Similar improvements were noted in the active warming group for anxiety and nausea compared with little, if any, improvement in the passive warming group.

Bottom Line: Local active warming with an electric heating blanket to the lower abdomen and back reduces the pain, anxiety, and nausea caused by renal colic secondary to urolithiasis. This is certainly worth trying on the way to the hospital or the pharmacy. (Level of Evidence: 2b)