Health-related quality of life after tricompartment knee arthroplasty with and without an extended-duration continuous femoral nerve block: a prospective, 1-year follow-up of a randomized, triple-masked, placebo-controlled study.
BACKGROUND
We previously provided evidence that extending an overnight continuous femoral nerve block to 4 days after tricompartment knee arthroplasty (TKA) provides clear benefits during the perineural infusion in the immediate postoperative period. However, it remains unknown if the extended infusion improves subsequent health-related quality of life between 7 days and 12 mo.


METHODS
Patients undergoing TKA received a femoral perineural infusion of ropivacaine 0.2% from surgery until the following morning, at which time patients were randomized to either continue perineural ropivacaine (n = 25) or normal saline (n = 25) in a double-masked fashion. Patients were discharged with their catheter and a portable infusion pump, and catheters were removed on postoperative day 4. Health-related quality of life was measured using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index preoperatively and then at 7 days, as well as 1, 2, 3, 6, and 12 mo after surgery. The WOMAC evaluates three dimensions of health-related quality of life: pain, stiffness, and physical functional disability. For inclusion in the analysis, we required a minimum of 4 of the 6 time points, including day 7 and at least 2 of mo 3, 6, and 12.


RESULTS
The two treatment groups had similar WOMAC scores for the mean area under the curve calculations (point estimate for the difference in mean area under the curve for the two groups [overnight infusion group-extended infusion group] = 1.2, 95% confidence interval: -5.6 to +8.0; P = 0.72) and at all individual time points (P > 0.05).


CONCLUSIONS
We found no evidence that extending an overnight continuous femoral nerve block to 4 days improves (or worsens) subsequent health-related quality of life between 7 days and 12 mo after TKA. (ClinicalTrials.gov number, NCT00135889.).
Ilfeld
Brian M
BM
Department of Anesthesiology, UCSD Center for Pain Medicine, 9300 Campus Point Dr.-MC 7651, LA Jolla, CA 92037-7651, USA. bilfeld@ucsd.edu
Meyer
R Scott
RS
Le
Linda T
LT
Mariano
Edward R
ER
Williams
Brian A
BA
Vandenborne
Krista
K
Duncan
Pamela W
PW
Sessler
Daniel I
DI
Enneking
F Kayser
FK
Shuster
Jonathan J
JJ
Maldonado
Rosalita C
RC
Gearen
Peter F
PF
D000577:Amides / Q000008:administration & dosage* / Q000009:adverse effects; D000700:Analgesics / Q000627:therapeutic use; D000779:Anesthetics, Local / Q000008:administration & dosage* / Q000009:adverse effects; D019645:Arthroplasty, Replacement, Knee; D002404:Catheterization; D004185:Disability Evaluation; D004334:Drug Administration Schedule; D005267:Femoral Nerve; D005500:Follow-Up Studies; D006801:Humans; D007260:Infusion Pumps; D009407:Nerve Block; D020370:Osteoarthritis, Knee / Q000503:physiopathology / Q000601:surgery*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000517:prevention & control*; D011446:Prospective Studies; D011788:Quality of Life; D020127:Recovery of Function; D000077212:Ropivacaine; D013997:Time Factors; D016896:Treatment Outcome
D000577:Amides; D000700:Analgesics; D000779:Anesthetics, Local; D000077212:Ropivacaine