Swallowing Impairment During Propofol Target-Controlled Infusion

BACKGROUND:

Sedatives can impair the swallowing process. We assessed the incidence and severity of swallowing impairment in patients sedated with propofol at clinically relevant doses. We also identified factors that were predictive of swallowing impairment.

METHODS:

In 80 patients scheduled to undergo elective gastrointestinal endoscopy under target-controlled infusion (TCI) propofol sedation, swallowing was evaluated by glottis videoendoscopy, using the Dysphagia Severity Score (DSS) and the Penetration and Aspiration Scale (PAS). The level of sedation was assessed with the Observer’s Assessment of Alertness/Sedation (OAAS) scale. Evaluations were obtained within each patient at 3 target effect-site propofol concentrations of 2, 3, and 4 μg/mL (Marsh model).

RESULTS:

At 2 μg/mL TCI, the OAAS score was 2 in 21 (26.25%) patients and 1 in 59 (73.75%). The OAAS score was 1 in all patients at 3 and 4 μg/mL TCI target. At 3 μg/mL TCI target, 19 (24.36%) patients had a DSS = 3 and 18 patients (23.08%) had a PAS = 7–8 (severe swallowing impairment). DSS was associated with increasing age (5-year odds ratio [OR] 1.53 [1.22–1.93]; P < 0.001), body mass index (BMI; OR 1.24 [1.08–1.42]; P = 0.002), and TCI target (OR 15.80 [7.76–32.20]; P < 0.001). In an alternative model incorporating OAAS instead of TCI target, DSS was associated with increasing age (5-year OR 1.13 [1.02–1.24]; P = 0.014) and BMI (OR 1.08 [1.02–1.15]; P = 0.006) and decreasing OAAS (OR 0.05 [0.006–0.36]; P = 0.003). PAS was associated with increasing age (5-year OR 1.09 [1.04–1.15]; P < 0.001), BMI (OR 1.23 [1.07–1.41]; P = 0.003), and TCI target (OR 15.23 [7.45–31.16]; P < 0.001). In an alternative model incorporating OAAS instead of TCI target, PAS was associated with increasing age (5-year OR 1.14 [1.04–1.26]; P = 0.007) and BMI (OR 1.09 [1.02–1.15]; P = 0.006) and decreasing OAAS (OR 0.05 [0.006–0.41]; P = 0.005).

CONCLUSIONS:

Aspiration due to swallowing impairment may occur during deep sedation produced by propofol at commonly used TCI targets. TCI targets are predictors of swallowing impairment; increased age and high BMI are concomitant risk factors.