Programmpunkt

10:23–10:31

Titel: Increased postoperative dexamethasone and gabapentin reduces opioid consumption after total knee arthroplasty
ID: KV 19
Art: Kurzvortrag
Redezeit: 6 + 2 min
Session: Kurzvorträge – Endoprothetik Knie

Referent: Felix Wunderlich (Mainz)


Abstract - Text

Introduction

Postoperative pain after total knee arthroplasty (TKA) has been shown to impede early recovery after surgery and lead to poor patient satisfaction. While reliably alleviating severe pain, opioid analgesics are well known to cause nausea, obstipation, sedation and have a relevant addiction potential. Dexamethasone and gabapentin are used in multimodal pain management protocols to reduce postoperative pain after total knee arthroplasty (TKA). For both analgesic adjuvants the optimal dose regimen to reduce opioid usage is still unclear.

In this study we aimed to investigate whether a postoperative high-dose dexamethasone and gabapentin protocol reduces the opioid consumption after TKA when compared to a low-dose protocol.

Methods

We retrospectively compared the opioid consumption of patients undergoing primary unilateral TKA before and after a change of the analgesic adjuvant medication in our protocol (old protocol (old): 4 mg of dexamethasone daily for 2 days, 600 mg gabapentin daily for one week; new protocol: 10 mg dexamethasone daily for 2 days, 300 mg gabapentin every 8 hours for one week). All surgeries were performed under spinal anesthesia. Peri- and postoperative pain medication regimens remained unchanged. The study was performed at a high volume arthroplasty center using fast track surgery principles and all surgeries were performed by a single surgeon. Institutional review board approval was granted.

Results

186 patients who received TKA between 11/29/2016 and 06/09/2017 were screened.  6 patients who had general anesthesia, 4 patients who had simultaneous bilateral TKA and 16 patients with ongoing opioid consumption at the time of surgery were excluded, leaving 80 patients in each group. There were no differences in patient characteristics among the two groups.

Opioid consumption within 24h (mean morphine equivalents in mg: 50.5, standard deviation (SD) 30.0 (old) vs. 39.8, SD 24.2 (new); P=0.0470]), 48h (97.3 (SD 64.4) vs. 70.4 (SD 51.2) P=0.0040) and 72h (108.1 (SD 79.5) vs. 82.5 (SD 72.6) P=0.0080) was significantly lower for patients treated after the change of the protocol.

When only analyzing patients who were treated per protocol, opioid consumption in the new protocol group was again significantly lower at 48h (90.1 (57.3) old vs. 69.8 (55.5) new P=0.0179) and 72h (98.4 (62.2) old vs. 82.8 (80.3) new P=0.0261) but did not reach the level of significance at 24h (46.5 (29.9) old vs. 40.5 (26.1) new P=0.2980).

Conclusion

Increased postoperative administration of Dexamethasone and Gabapentin after TKA is associated with lower opioid consumption. Within the first 48h after TKA up to about 25% of opioids can be spared when comparing high-dose to low-dose protocols.  To our knowledge, this study is the first to assess the effect of a prolonged and increased administration of these analgesic adjuvant medications on opioid consumption. Our results encourage further investigation of high-dose dexamethasone and gabapentin in randomized controlled trials.