Abstract
Purpose:
To investigate treatment patterns and efficacy of postoperative strong opioids in patients who underwent total knee arthroplasty (TKA) in Korea
Methods:
A prospective, non-interventional study of 301 patients who underwent TKA and received strong opioids following patient controlled analgesia (PCA) was conducted by reviewing patient charts and diaries from 19 teaching hospitals. Clinical characteristics, strong opioid treatment patterns, efficacy of strong opioid on a scale of 0–10, and opioid-related adverse events (AEs) were investigated during hospitalization and at first outpatient visit. Safety analysis was conducted on 301 patients, and efficacy analysis was conducted on full analysis set (FAS) which consisted of all the patients who had at least 1 efficacy result among 301 patients.
Results:
Among the FAS population of 298 patients, 86.9% were female, and mean age was 68.7 ± 7.5 years. Average duration of PCA was 4.3 ± 1.7 days, and average length of hospital stay including surgery was 16.3 ± 7.6 days. The mean duration of strong opioid prescription on a regular basis between PCA discontinuation and discharge was 10.3 ± 6.7 days. At the initial treatment with strong opioid following PCA, mean pain intensity score was 6.1 ± 2.1 upon movement and 4.2 ± 2.4 at rest. At discharge, mean pain intensity score was 4.1 ± 1.9 upon movement and 2.3 ± 1.8 at rest. Meanwhile, pain intensity score at the first outpatient visit was assessed only in 146 patients (49.0%) treated with opioid, and mean pain intensity scores upon movement and at rest were 3.5 ± 2.1 and 1.7 ± 1.8, respectively. Most frequently prescribed opioid was oral oxycodone (47.4%), followed by pethidine injection (17.2%), oral oxycodone/naloxone (12.6%), and transdermal fentanyl (12.0%). Additionally, the most frequently prescribed opioid on a regular basis was oral oxycodone (53.3%), and that on a PRN (pro re nata) basis was pethidine injection (48.4%). Among treatments, mean duration and mean daily dose of oral oxycodone during hospitalization were 6.1 ± 5.6 days and 13.9 ± 8.2 mg, 1.6 ± 1.2 days and 45.5 ± 24.5 mg for pethidine injection, 7.3 ± 5.3 days and 16.2 ± 7.3 mcg/hr for transdermal fentanyl, and 9.4 ± 8.0 days and 23.2 ± 16.8 mg/11.6 ± 8.34 mg for oral oxycodone/naloxone. At discharge, 150 patients (50.3%) were prescribed opioids. The most frequently prescribed strong opioid as discharge medications and their mean daily dose were 17.9 ± 10.5 mg of oxycodone (56.6%), 26.8 ± 17.0 mg/13.4 ± 8.5 mg of oxycodone/naloxone (17.1%), and 15.9 ± 6.1 mcg/hr of fentanyl (11.4%). Of 301 patients, 36 opioid-related AEs were reported in 26 patients (8.6%); the most frequently reported opioid-related AEs were nausea/vomiting in 13 patients (4.3%) experiencing 17 events, constipation in 10 patients (3.3%) experiencing 10 events, and sedation in 3 patients (1.0%) experiencing 3 events.
Conclusion:
The first nationwide non-interventional study was conducted to investigate treatment patterns and efficacy of strong opioids in patients who underwent TKA. Among these patients, strong opioids provided favorable pain relief and were well tolerated at relatively low dose following PCA till the first outpatient visit.
