The Influence of Ongoing Opioid Use in Patients with Ultrasound

Guided Blocks for Shoulder and Knee Surgeries, a 6-Month Review

C. Gibbs, M. Fredericks S. Ahmadzadeh, K. Skidmore, D. Duplechin, C. Rodriguez, S. Shekoohi, A. Kaye

Department of Anesthesiology, Louisiana State University Health Shreveport

 

INTRODUCTION

Opioid prescriptions postoperatively have

increased over the last several decades. While

effective at treating acute pain following surgery,

prolonged use is associated with risks of

tolerance, addiction, and overdose. The opioid

crisis has pushed legislature and medical

groups to investigate alternative methods to

control acute postoperative pain. The literature

shows that regional anesthesia is strongly

associated with reduced opioid use in the

immediate 72 hours postoperatively, but little

research tracks how opioid consumption varies

long term (1, 2).

This study tests the hypothesis that regional

anesthesia utilization is associated with a

sustained reduction in opioid consumption at 1, 3,

and 6 months postoperatively.

 

GOALS AND OBJECTIVES

We hypothesize that controlling acute pain after

orthopedic surgeries reduces the incidence of

chronic opioid use. To examine whether there is a

dose-response effect, we built upon the fact that

the peripheral nerve block (PNB) we utilize before

upper body orthopedic surgery (interscalene

nerve block) may be more effective than our most

performed PNB before lower body surgery

(adductor canal). This stems from the FDA

indication allowing long-acting local anesthetic

injection in the interscalene PNB, while not in the

adductor canal block. Additionally, the adductor

canal block often misses additional pain fibers. To

control for confounding variables, we examined if

patients were preoperatively prescribed opioids,

along with other baseline characteristics.

 

MATERIALS & METHODS

We obtained IRB approval from Louisiana State

University Health Sciences Shreveport for our

retrospective study of electronic medical records.

All patients undergoing orthopedic surgery in the

ambulatory center at St Mary Medical

Center between July 2021 and July 2024 were

included for screening. The inclusion criteria

included total shoulder arthroplasty (TSA), reverse

total shoulder arthroplasty (TRSA), or knee

arthroscopy. The primary outcome was an opioid

refill prescription at 1 month, 3 months, and 6

months postoperatively. The confounding variables

examined were preoperative prescription of opioids,

age, sex, race, obesity, diabetes, hypertension,

chronic pulmonary disease, arthritis, and the

identity of the prescribing surgeon. The primary

research variable was placement of a PNB. A

secondary research variable was upper or lower

body surgery. Chi square analysis was used for

one-month opioid refill incidence of the primary and

secondary variables, as well as the preop

confounding variables using SAS software.

 

RESULTS

Of 522 patients who underwent a TSA, TRSA, or

knee arthroscopy, 56 (10.73%) did not receive a

preoperative PNB. Among this "placebo" group,

5.36% required opioid refills at 1 month, 3.57% at 3

months, and 0% at 6 months. Of those who

received a PNB, postoperatively, 15.07% required

opioid refills at one month, 2.95% at 3 months, and

0.91% at 6 months. Statistical analysis by SAS

software and t-test showed opioid use declined

after 1 month. No significant difference in opioid

consumption among patients with comorbidities

 

RESULTS (CONTINUED)

was detected, although one surgeon prescribed significantly more

opioids. PNB was associated with an increased use of opioids at 1

month, although not significantly (p=0.057 with Yates' correction).

14.12% of patients having upper body surgery with a PNB required

opioid refills at 1 month compared to 20.8% of patients having lower body

surgery with a PNB (p=0.0807).

 

DISCUSSION

While not all the data at the 3- and 6-month points could be collected

yet, these pilot data indicate 18% of patients required at least one opioid

refill within 6 months of TSA, RTSA, or knee arthroscopy, despite

receiving a PNB. Chronic opioid use postoperatively at one month was

not significantly related to age, sex, race, or comorbidities. Data is

currently pending in 5.6% and 15.9% of patients for the 3- and 6-month

points, respectively. When comparing the upper and lower body surgery

 

DISCUSSION (CONTINUED)

groups at 1 month, the lower body group demonstrated an absolute 6.68

percentage points higher incidence in opioid prescription. This could be

because Exparel(R)'s long-acting bupivacaine FDA indications limit use

to upper body one-shot PNB. Additionally, knee surgery is notoriously

nearly the most painful surgical site and is fed by sciatic nerve branches

missed by our most common PNB, adductor canal.

One limitation of this study is sample size. To prove a drop in

incidence in opioid refills at one month, an increase to n1=892 and

n2=298 is needed for upper and lower body surgery, respectively.

 

CONCLUSIONS

Our results suggest PNB prior to orthopedic surgery does not

significantly reduce opioid use at one month postoperatively. However,

the location and duration of the medications in the PNB may influence

the need for opioid refills.

Our future research in this study group will include searches for why

the patients without a PNB requested fewer opioid refills, such as

different preoperative opioid regimen or nonopioid techniques. One

possibility is the severe rebound pain after a short-acting-one shot PNB

wears off can stimulate a high incidence of opioid refills at 1 month.

 

REFERENCES

1. Ozen M, Inan N, Tümer F, Uyar A, Baltaci B. The effect of 3-in-1

femoral nerve block with ropivacaine 0.375% on postoperative morphine

consumption in elderly patients after total knee replacement

surgery. Agri. 2006;18(4):44-50.

2. Vijittrakarnrung C, Freshman R, Anigwe C, Lansdown DA, Feeley BT,

Ma CB. Periarticular injection in addition to interscalene nerve block can

decrease opioid consumption and pain following total shoulder

arthroplasty: a comparison cohort study. J Shoulder Elbow

Surg2023;32(12):e597-e607. doi:10.1016/j.jse.2023.05.009