Risk Factors for Airway Management-Related Lip Injuries in Surgery: A Prospective Matched Case-Control Study
Thitima Chinachoti MD*, Wiriya Maisat MD*, Thunshuda Sumphaongern MD*
Affiliation : * Department of Anesthesiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Objective : To prospectively investigate data specific to 9 risk factors for significant association with airway management-
related lip injuries during surgery.
Material and Method: Two hundred and seventy patients (90 cases and 180 controls) who underwent surgeries at Siriraj
Hospital from September 2015 to July 2016 were enrolled. Ninety patients (injured group) sustained lip injury after surgery.
Each case was matched with two cases without lip injury by gender, age, and operation date. One hundred and eighty patients
without lip injury were recruited as control group. Data specific to 9 risk factors were evaluated for significant association
with airway management-related lip injuries during surgery.
Results : Most patients recovered from their lip injury within three days after operation, but 8 patients or 8.4% required as
long as 5 days for their lip injury to completely heal. Predisposing factors associated with airway management-related lip
injuries in univariate analysis were Mallampati grade >1, dental problems, performed by nurse anesthetist, training duration
<3 months and 3 to 6 months, and oral procedure. Significant factors associated with airway management-related lip injuries
in multivariate analysis were dental problems (OR 8.9, 95% CI 1.46 to 4.21, p = 0.001), training duration <6 months (OR
16.2, 95% CI 4.2 to 62.5, p<0.001) and oral procedure (OR 19.3, 95% CI 3.5 to 105.8, p = 0.001).
Conclusion : Preexisting dental problems, oral procedures, and airway management performed by an operator with less
than six month training are risk factors for airway management related injuries. Careful protection and closed observation
should be particularly concerned.
Keywords : Lip injuries, Anesthesia, Risk factors
