Introduction: To ensure good rehabilitation and improved outcomes following total hip arthroplasty (THA), optimal pain control is necessary. Newer methods of pain control have been advocated, as current modalities have been associated with undesirable side effects and serious complications. One such modality is liposomal bupivacaine, which provides long-acting, slow-release analgesia. The purpose of this study was to evaluate: (1) lengths of hospital stay and (2) the discharge status of patients who underwent THA with liposomal bupivacaine compared to a cohort who received standard analgesic regimens.
Materials and methods: We utilized a hospital discharge database from July 1, 2013 to June 30, 2014, which included 7,704,919 patients for our analysis. We selected patients aged 18 years or older who had an inpatient stay for THA using ICD-9 procedure code (ICD-9-CM = 81.51), which resulted in 55,129 THA patients. Patients who had a nerve block in the time period from the surgery date to the discharge date were then excluded, which resulted in 54,604 THA patients. The THA cohort who received liposomal bupivacaine suspension consisted of 5,267 patients (2,907 women; 2,360 men) who had a mean age of 64 years, while the THA without injections or nerve block consisted of 49,337 patients who had a mean age of 65 years that consisted of 27,530 women and 21,807 men. We analyzed length-of-stay by controlling for race, region, age, sex, Charlson Index, and operating time using a log link linear model with a negative binomial distribution. The discharge status to home compared to short-term nursing facility or rehabilitation was analyzed using logistic regression while controlling for the aforementioned covariates.
Results: The mean lengths of stay, after adjusting for covariates, for the liposomal bupivacaine cohort was significantly shorter than the no injection cohort. The distribution of patients being discharged to home compared to a short-term nursing facility or a rehabilitation facility was higher in the liposomal bupivacaine cohort compared to the cohort who did not receive liposomal bupivacaine. Multivariate logistic regression analyses demonstrated a higher likelihood of being discharged to home in liposomal bupivacaine cohort when compared to no injection.
Conclusion: Liposomal bupivacaine appears to be an effective pain relief modality that leads to reduced lengths of hospital stay and increased rates of discharge to home. This may be an appropriate addition for the analgesic armamentarium in patients who undergo THA.