A prospective, randomized trial of liposomal bupivacaine compared to conventional bupivacaine on pain control and postoperative opioid use in adults receiving adductor canal blocks for total knee arthroplasty

Table 1 Demographic and clinical characteristics of the study group, stratified by treatment arm

Variable^a	Bupivacaine type used in adductor canal block (treatment arm)
Variable^a	Liposomal^b	Conventional
N	40	40
Age (years)	68.0 ± 9.0	69.1 ± 8.8
BMI (kg/m²)	29.8 ± 4.6	28.8 ± 5.6
Male sex	20 (50.0%)	16 (40.0%)
Race/ethnicity
White	39 (97.5%)	40 (100.0%)
Black or African American	1 (2.5%)	0 (0.0%)
Active Smoking	2 (5.0%)	1 (2.5%)
ASA class
1	2 (5.0%)	1 (2.5%)
2	29 (72.5%)	33 (82.5%)
3	9 (22.5%)	6 (15.0%)
Comorbidities
Depression	10 (25.0%)	16 (40.0%)
Anxiety/PTSD	12 (30.0%)	10 (25%)
Chronic pain	2 (5.0%)	4 (10.0%)
Fibromyalgia	1 (2.5%)	0 (0.0%)
Pre-operative medications
Opioids < 90 MME/day	2 (5.0%)	1 (2.5%)
Antidepressants	7 (17.5%)	12 (30.0%)
Anti-anxiety	4 (10.0%)	1 (2.5%)
Gabapentin	1 (2.5%)	1 (2.5%)
Initial anesthesia type
General	3 (7.5%)	1 (2.5%)
Spinal	37 (92.5%) ^c	39 (97.5%)
Intraoperative pain management
Opioids
Received intraoperative opioids, n (%)	10 (25.0%)	10 (25.0%)
Total opioid dose if received (MME)	30 (15–47.5)	22.5 (10–32.5)
Non-opioids
Received ketorolac, n (%)	2 (5.0%)	0 (0.0%)
Ketorolac dose if received (mg)	15, 15	None
Ketamine
Received ketamine, n (%)	25 (62.5%)	24 (60.0%)
Ketamine dose if received (mg)	40 (22.5–50)	50 (31.9–50)
Time to perform block (min)	2.2 ± 0.4	2.0 ± 0.2
Duration of anesthesia (h)	1.6 ± 0.2	1.6 ± 0.2

ASA American Society of Anesthesiologists, PTSD post-traumatic stress disorder, MME morphine milligram equivalents
^aData shown as n (%) or as mean ± standard deviation
^bOne patient received an adductor canal block with liposomal bupivacaine and 0.5% (instead of 0.25%) conventional bupivacaine
^cOne patient was subsequently converted to general anesthesia, as could not place spinal

ISSN: 2524-7948