Warm intranasal saline irrigation reduces intraoperative blood loss during functional endoscopic sinus surgery: a...

To evaluate whether warm intranasal saline irrigation (38-40 °C) during functional endoscopic sinus surgery (FESS) is associated with reduced intraoperative bleeding compared with standard cold irrigation (18-21 °C).

We performed a single-centre retrospective cohort study of consecutive FESS procedures under inhalational general anaesthesia (January 2017-December 2022). After exclusions, 1,990 cases were eligible. One-to-one propensity score matching (age, sex, ASA class, and type of inhaled anaesthetic) yielded 409 warm and 409 cold cases. Primary outcomes were estimated blood loss and blood loss >50 mL. Secondary outcomes included anaesthesia duration, intraoperative medication requirements, and lowest recorded temperature. Multivariable logistic regression adjusted for BIS monitoring utilisation, intravenous fluid rate, and intraoperative antihypertensive medication use.

Median blood loss was 50 mL (IQR 50-50) with warm irrigation versus 50 mL (IQR 50-100) with cold irrigation (p = 0.001). Blood loss >50 mL occurred in 18.6% versus 32.0%, respectively (p < 0.001). Warm irrigation remained independently associated with lower odds of blood loss >50 mL (adjusted OR 0.45, 95% CI 0.31-0.66; p < 0.001). BIS monitoring was also protective (adjusted OR 0.57, 95% CI 0.37-0.87; p = 0.009). Warm irrigation was associated with shorter anaesthesia duration (median 2.82 vs 3.38 h; p < 0.001) and a slightly higher nadir temperature (35.6 vs 35.5 °C; p = 0.007).

Warm intranasal saline irrigation at 38-40 °C was associated with fewer clinically significant bleeding events during routine FESS and may represent a simple, low-cost adjunct to perioperative haemostatic management.