Non-opioid analgesic modes of pain management are associated with reduced postoperative complications and resource utilisation: a retrospective study of obstructive sleep apnoea patients undergoing elective joint arthroplasty.

BACKGROUND: Studies on the effectiveness of multimodal analgesia, particularly in patients at higher perioperative risk from obstructive sleep apnoea (OSA), are lacking. We aimed to assess the impact of multimodal analgesia on opioid use and complications in this high-risk cohort. METHODS: We conducted a population-based retrospective cohort study of OSA patients undergoing elective lower extremity joint arthroplasty (2006-16, Premier Healthcare database). Multimodal analgesia was defined as opioid use with the addition of one, two, or more non-opioid analgesic modes including, nonsteroidal anti-inflammatory drugs (NSAIDs), cyclooxygenase-2 inhibitors, paracetamol/acetaminophen, peripheral nerve blocks, steroids, gabapentin/pregabalin, or ketamine. Multilevel multivariable regression models measured associations between multimodal analgesia and opioid prescription (primary outcome; oral morphine equivalents). Secondary outcomes included opioid- and OSA-related complications, and resource utilisation. Odds ratios (OR) or % change and 95% confidence intervals (CI) are reported. RESULTS: Among 181 182 OSA patients included, 88.5% (n = 160 299) received multimodal analgesia with increasing utilisation trends. Multivariable models showed stepwise beneficial postoperative outcome effects with increasing additional analgesic modes compared with opioid-only analgesia. In patients who received more than two additional analgesia modes (n = 64 174), opioid dose prescription decreased by 14.9% (CI -17.0%; -12.7%), while odds were significantly decreased for gastrointestinal complications (OR 0.65, CI 0.53; 0.78), mechanical ventilation (OR 0.23, CI 0.16; 0.32), and critical care admission (OR 0.60, CI 0.48; 0.75), all P<0.0001. CONCLUSIONS: In a population at high risk for perioperative complications from OSA, multimodal analgesia was associated with a stepwise reduction in opioid use and complications, including critical respiratory failure.

Postoperative delirium in total knee and hip arthroplasty patients: a study of perioperative modifiable risk factors.

BACKGROUND: Postoperative delirium continues to pose major clinical difficulties. While unmodifiable factors (e.g. age and comorbidity burden) are commonly studied risk factors for delirium, the role of modifiable factors, such as anaesthesia type and commonly used perioperative medications, remains understudied. This study aims to evaluate the role of modifiable factors for delirium after hip and knee arthroplasties. METHODS: We performed a retrospective study of 41 766 patients who underwent hip or knee arthroplasties between 2005 and 2014 at a single institution. Data were collected as part of routine patient care. Multivariable logistic regression models assessed associations between anaesthesia type and commonly used perioperative medications (opioids, benzodiazepines, and ketamine) and postoperative delirium. Odds ratios (OR) and 95% confidence intervals (CI) are reported. Various sensitivity analyses are also considered, including multiple imputation methods to address missing data. RESULTS: Postoperative delirium occurred in 2.21% (n=922) of all patients. While patients who received neuraxial anaesthesia were at lower risk for postoperative delirium (compared with general anaesthesia; epidural OR 0.59 CI 0.38-0.93; spinal OR 0.55 CI 0.37-0.83; combined spinal/epidural OR 0.56 CI 0.40-0.80), those given intraoperative ketamine (OR 1.27 CI 1.01-1.59), opioids (OR 1.25 CI 1.09-1.44), postoperative benzodiazepines (OR 2.47 CI 2.04-2.97), and ketamine infusion (OR 10.59 CI 5.26-19.91) were at a higher risk. CONCLUSIONS: In this cohort of hip and knee arthroplasty patients, anaesthesia type and perioperative medications were associated with increased odds for postoperative delirium. Our results support the notion that modifiable risk factors may exacerbate or attenuate risk for postoperative delirium.