Local heating of the wound with dressings soaked in saline at 42 °C can reduce postoperative bleeding: a single-blind, split-mouth, randomised controlled clinical trial

Control of bleeding is essential during oral procedures. Although various chemical agents have been introduced and tested, hot water dressing has not to our knowledge been assessed before. Studies of operations for epistaxis or sinus conditions have suggested that irrigation with hot water can reduce bleeding, so we hypothesised that it might be effective in reducing bleeding after extraction too. Ten patients who required bilateral extractions took part in this split-mouth, randomised, single-blind, controlled clinical trial. After extraction, sockets were packed with similar gauze dressings soaked in normal saline 4 ml at room temperature (control) and warmed to 42 °C (experimental). The extent of bleeding on each side was measured by subtracting the original weight of the gauze from its weight after absorption of blood. The difference between the weights was compared using Student's paired t test (α = 0.05, β < 0.05). Mean (SD) weights were 22.1(2.2) g and 18.4 (2.5) g in the control and experimental groups, respectively, indicating an 18% reduction in the experimental group (p = 0.002). Soaking gauze in normal saline heated to 42 °C can reduce bleeding after extraction.