Low Incidence of Postoperative Respiratory Depression with Oliceridine Compared to Morphine: A Retrospective Chart Analysis

Figure 3

Incidence of opioid-induced respiratory depression (primary outcome). Using the Inverse probability weighting (IPW) approach patients in the CO cohort were balanced with those in the oliceridine cohort in several prespecified characteristics, including age, sex, site, illness comorbidities, American Society of Anesthesiologists (ASA) status, and type of surgical procedure. The IPW approach weights patient observations based on a propensity score, which is defined as the weighted probability of a patient belonging to a specific cohort. Propensity scores were estimated using a multivariate logistic regression model conditional on the observed baseline covariates (surgical procedure type, ASA status, age, sex, race [characterized as white/nonwhite], and BMI). Matched cohort consisted of 95 subjects in either cohort with a direct one-to-one (1 : 1) matching approach on the same observed matching variables used in the complete IPW balanced sample. For the oliceridine cohort, OIRD events were prespecified, as defined in the original study protocol for all patients based on verbatim clinical terms coded using adverse event methodology defined in MedDRA reporting terminology (MedDRA, version 19.0). For the CO cohort, ICD-9 and ICD-10 codes were obtained as recorded in each patient’s chart review and entered into their accompanying Electronic Medical Record (EMR). A total of 206 patients (91.6%) in the CO cohort received other opioids concomitantly or after treatment with IV morphine. Incidence of respiratory events was significantly lower in the oliceridine cohort.