Small dose of naloxone as an adjuvant to bupivacaine in intrapleural infiltration after thoracotomy surgery: a prospective, controlled study

Abstract

Background Severe pain always develops after thoracotomy; intrapleural regional analgesia is used as a simple, safe technique to control it. This study was performed to evaluate whether a small dose of naloxone with local anesthetics prolongs sensory blockade. Methods A prospective, randomized double-blinded controlled study was conducted on 60 patients of American Society of Anesthesiologists statuses I and II, aged 18 to 60 years, scheduled for unilateral thoracotomy surgery. After surgery, patients were randomly divided into two groups: through the intrapleural catheter, group B received 30 ml of 0.5% bupivacaine, while group N received 30 ml of 0.5% bupivacaine with 100 ng of naloxone. Postoperative pain was assessed using the visual analog pain scale (VAS). Time for the first request for rescue analgesia, total amount consumed, and incidence of postoperative complications were also recorded. Results The VAS score significantly decreased in group N, at 6 h and 8 h after operation ( P < 0.001 for both). At 12 h after injection, the VAS score increased significantly in group N ( P < 0.001). The time for the first request of rescue analgesia was significantly longer in group N compared to group B ( P < 0.001). The total amount of morphine consumed was significantly lower in group N than in the bupivacaine group ( P < 0.001). Conclusions Addition of a small dose of naloxone to bupivacaine in intrapleural regional analgesia significantly prolonged pain relief after thoracotomy and delayed the first request for rescue analgesia, without significant adverse effects.

A Low Dose of Naloxone Added to Ropivacaine Prolongs Femoral Nerve Blockade: A Randomized Clinical Trial

“…The authors reported that naloxone increased the sensory block duration by approximately 3 h. Recovery of the sensory block was slower in the naloxone mixed group than in the control group. Similarly, Amer and Omara [ 14 ] showed that a low dose of naloxone prolonged intrapleural infiltration after surgery involving thoracotomy. Based on the previous studies, we applied it for the first time to the femoral nerve block with a low dose of naloxone to a ropivacaine solution.…”

“…Previous studies examining the use of naloxone to alleviate pain when added in small amounts to LA in various neural blockade procedures have been published [ 11 – 14 ]. Movafegh et al [ 12 ] studied the effect of appending a low dose of naloxone to a lidocaine solution for axillary blockade and reported that this combination prolongs motor and sensory blockade, with a significantly increased interval to the first sensation of postoperative pain in the naloxone group.…”

“…First, our results regarding secondary outcomes were only able to be generalized in the context of systemic multimodal analgesia and LIA, and the results may be different in the absence of any multimodal analgesic interventions. Second, since this is the first time that low-dose naloxone with FNB was administered, the value (258 min difference) extracted from the results of a previous study [ 14 ] was used to calculate the sample size. Each included group was relatively small and underpowered to detect significant differences that could be caused by a difference from the value (133 min difference) of this study.…”

“…The sample size was calculated based on a previous study in which the patient received a similar postoperative analgesia regimen. In that study, the time of first rescue analgesia was 402 ± 54 min in the placebo group and 660 ± 48 min in the intervention group [ 14 ]. The study power was 90%, and the alpha level was 0.05.…”

“…Based on accumulating evidence, excitatory effects of opioids are selectively blocked by naloxone [ 9 , 10 ]. This drug has been administered in low doses as an additive to local anesthetic (LA) medications to prolong motor and sensory nerve blocks during supraclavicular and axillary brachial plexus blockade and intrapleural infiltration [ 11 – 14 ].…”