ASA SCORE AND OBESITY, BUT NOT AGE, INCREASE COMPLICATIONS OF ENDOSCOPIST-BASED PROPOFOL SEDATION FOR EUS

Aims The aim of our study was to study risk factors, safety and complications of endoscopist-guided propofol sedation for upper EUS in patients with comorbidities, obese or age>65.

Methods Patients referred for EUS from January-2011 to May-2019 were included. We compared complications between patients under 65 years-old and older than 65, BMI< 35 and above 35, and patients classified as ASA 1-2, and the ones with ASA 3-4. Baseline characteristics such as pulse or oxygen saturation were compared. Complications such as hypoxemia, hypotension or cardiac rhythm abnormalities were also compared. Propofol dosages were studied.

Results 2975 patients (48,6% male) were included. 1338 (45%) were older than 65 years, 743 (25%) were ASA III-IV and 27 (1%) were obese. Older patients had a lower basal oxygen saturation (97%vs98,5%; p< 0,0001), so did ASA3-ASA4 patients (96,7%vs.98,1%; p=0,005). No differences were found in heart rate between those groups, nor in obese/lean patients. Propofol doses were lower in old patients (p< 0,0001), and ASA3-ASA4 (p< 0,0001). In obese individuals, induction doses were different with respect to lean patients, but not reinjection doses (p< 0,0001). The bivariate analysis showed that older patients (3.6% vs. 2%; p< 0.008), ASA3-ASA4 patients (4.6%vs.2.19%; p< 0.001), and obese patients (26%vs.4.7%; p< 0.01) suffered desaturation more frequently. ASA3-ASA4 patients had an increase rate of bradycardia (0.7% vs. 0.13%; p=0.014). When considered all complications related to sedation (desaturation, bradycardia and hypotension) in a logistic regression analysis, obesity (OR: 8.57; CI95%: 3.62-20.28; P< 0.0001) and comorbidities (ASA3-ASA-4) (OR: 2.04; CI95%: 1.44-3.01; p< 0.0001) were independently related with them, but not age, when corrected by the two other risk factors.

Conclusions Comorbidities and obesity are risk factors for adverse events when sedating patients for EUS. Older patients need lower doses of sedatives, being the other two factors but not age itself risk factors for complications.