Characteristics that increase the risk for pain on propofol injection

Background: Propofol for anesthesia has become increasingly popular for endoscopic procedures. However, pain on propofol injection (POPI) remains an issue with administration. The primary endpoint of this study was to identify patient characteristics and factors, such as IV site and gauge, that could predict the occurrence of POPI.

Methods: This was a prospective chart review study of 291 patients undergoing endoscopic procedures. The patient's demographics, intravenous (IV) site, and gauge were extrapolated. POPI was scored 0-3: 0 for no pain, 1 for minimal discomfort or awareness of sensation, 2 for discomfort but manageable/tolerable, and 3 for severe discomfort with writhing.

Results: 291 patient charts were reviewed. One patient was excluded for a lower extremity IV site. 225 (77.6%) had no pain, 48 (16.6%) grade 1 pain, 16 (5.5%) grade 2 pain, and 1 (0.3%) grade 3 pain. 137, 13, and 140 patients respectively had antecubital (AC), forearm, and hand IVs. Zero patients with an AC IV experienced a score greater than 1. Compared to AC, forearm IVs with pain of 2-3 had a univariate odds ratio (OR) of 11.3 (0.66,1.92; p-value < 0.001), and hand IVs had a univariate OR of 18.8 (2.46,143.3; p-value < 0.001) with a multivariable OR 15.2 (1.93,118.9; p-value 0.004). Patients with anxiety/depression and pain had a univariate OR 2.31 (1.09, 7.27; p-value 0.031) with a multivariable OR 2.85 (1.06, 7.74; p-value 0.039). SSRI/SNRI use had a univariate OR 1.56 (0.57,4.28; p-value 0.38). Alcohol use had a univariate OR 1.24 (0.39,3.91; p-value 0.71). Narcotic use had a Univariate OR 6.18 (1.49,25.6; p-value 0.012). Diabetic patients had a univariate OR of 1.42 (0.45,4.48; p-value 0.55). Chronic pain had a univariate OR of 3.11 (1.04,9.28; p-value 0.042). Females had a univariate OR 0.98 (0.37,2.63; p-value 0.95).

Conclusion: This study identified potential characteristics for having POPI. The incidence of POPI was statistically significant in patients with hand and forearm IVs compared to AC IV sites, larger IV gauges, history of depression/anxiety, history of chronic narcotic use, fibromyalgia, and chronic pain syndromes. This shows the potential of premedicating with analgesics or using AC sites on these select patients to help reduce the risk of POPI.