Efficacy of Pregabalin in Acute Postoperative Pain Under Different Surgical Categories: A Meta-Analysis

An Update on Nonopioids: Intravenous or Oral Analgesics for Perioperative Pain Management

Despite an appreciation for many unwanted physiologic effects from inadequate postoperative pain relief, moderate to severe postoperative pain remains commonplace. Although treatment options have evolved in recent years, the use of nonopioid analgesics agents can reduce acute pain-associated morbidity and mortality. This review focuses on the importance of effective postoperative nonopioid analgesic agents, such as acetaminophen, nonsteroidal anti-inflammatory agents, gabapentinoid agents, NMDA antagonists, alpha 2 agonists, and steroids, in opioid sparing and enhancing recovery. A careful literature review focusing on these treatment options, potential benefits, and side effects associated with these strategies is emphasized in this review.

Pregabalin can decrease acute pain and morphine consumption in laparoscopic cholecystectomy patients: A meta-analysis of randomized controlled trials

BACKGROUND

Pregabalin has been used as an adjunct for the management of acute pain in laparoscopic cholecystectomy. This meta-analysis aimed to illustrate the efficacy and safety of pregabalin for pain management following laparoscopic cholecystectomy.

METHODS

In March 2017, a systematic computer-based search was conducted in PubMed, EMBASE, Web of Science, Cochrane Database of Systematic Reviews, and Google databases. Data on patients prepared for laparoscopic cholecystectomy in studies that compared pregabalin versus placebo were retrieved. The primary endpoints were the visual analog scale (VAS) score with rest or mobilization at 6, 12, and 24 hours and total morphine consumption. The secondary outcomes were the morphine-related complications (i.e., nausea, vomiting, dizziness, somnolence, headache, pruritus, urine retention, respiratory depression, and blurred vision). Continuous outcomes were expressed as the weighted mean difference (WMD) with a corresponding 95% confidence interval (CI), and discontinuous outcomes were expressed as a risk ratio (RR) with a corresponding 95% CI.

RESULTS

Twelve clinical studies with 938 patients (gabapentin group = 536, control group = 402) were ultimately included in the meta-analysis. Pregabalin was associated with reduced pain scores with rest at 6, 12, and 24 hours, which corresponded to a reduction of 11.27 points at 6 hours, 9.46 points at 12 hours, and 3.99 points at 24 hours on a 100-point VAS. Moreover, pregabalin was associated with reduced pain scores with mobilization at 6, 12, and 24 hours, which corresponded to a reduction of 8.74 points, 5.80 points and 6.37 points at 6, 12, and 24 hours, respectively, on a 110-point VAS. Furthermore, pregabalin reduced the occurrence of nausea and vomiting. There were no significant differences in the occurrence of respiratory depression, pruritus, dizziness, blurred vision, and headache.

CONCLUSIONS

Pregabalin was efficacious in the reduction of postoperative pain, total morphine consumption, and morphine-related complications following laparoscopic cholecystectomy. In addition, a high dose of pregabalin was more effective than a low dose. The dose of pregabalin differed across the studies, and the heterogeneity was large. More studies are needed to verify the optimal dose of pregabalin in laparoscopic cholecystectomy patients.

The efficacy of pregabalin for the management of postoperative pain in primary total knee and hip arthroplasty: a meta-analysis

Objective

A systematic review of randomized controlled trials (RCTs) was conducted to evaluate the efficacy of pregabalin for the management of postoperative pain in patients undergoing primary total knee arthroplasty (TKA) and primary total hip arthroplasty (THA).

Method

The PubMed, Embase, Cochrane Central Register of Controlled Trials, and Google Scholar databases were searched for related articles using search strategy. RevMan 5.3 software was selected to conduct the meta-analysis.

Results

Seven RCTs were included in our meta-analysis. There were significant differences in visual analogue scale (VAS) at 24 and 48 h with rest, knee flexion degree, mean morphine consumption, and postoperative side effects (nausea, vomiting, pruritus, and dizziness) when comparing the pregabalin group to the placebo group after TKA and THA. However, the differences in VAS at 72 h with rest and at 24 h on movement were not significant between the two groups.

Conclusions

Pregabalin was found to improve pain control at 24 and 48 h with rest, reduce morphine consumption, improve the knee flexion degree, decrease the incident rate of nausea, vomiting, and pruritus, and increase the incident rate of dizziness after TKA and THA but could not improve the pain control at 72 h with rest. In summary, the use of pregabalin may be a valuable asset in pain management within the first 48 h after TKA and THA. However, future studies regarding doses and pregabalin medication are required.

Investigation of the predictive validity of laser-EPs in normal, UVB-inflamed and capsaicin-irritated skin with four analgesic compounds in healthy volunteers

AIMS

The aim of the present study was to assess the predictivity of laser-(radiant-heat)-evoked potentials (LEPs) from the vertex electroencephalogram, using an algesimetric procedure, testing the anti-nociceptive/anti-hyperalgesic effects of single oral doses of four marketed analgesics (of different compound classes) vs. placebo, in healthy volunteers with three skin types.

METHODS

This was a randomized, placebo-controlled, single-blind, five-way-crossover trial. Twenty-five healthy male/female Caucasians were included (receiving celecoxib 200 mg, pregabalin 150 mg, duloxetine 60 mg, lacosamide 100 mg or placebo) in a Williams design, with CO₂ laser-induced painful stimuli to normal, ultraviolet (UV) B-inflamed and capsaicin-irritated skin. LEPs and visual analogue scale ratings were taken at baseline and hourly for 6 h postdose from all three skin types.

RESULTS

In normal skin, the averaged postdose LEP peak-to-peak-(PtP)-amplitudes were reduced by pregabalin (-2.68 μV; 95% confidence interval (CI) -4.16, 1.19) and duloxetine (-1.73 μV; 95% CI -3.21, -0.26) but not by lacosamide and celecoxib vs. placebo. On UVB-irradiated skin, reflecting inflammatory pain, celecoxib induced a pronounced reduction in LEP PtP amplitudes vs. placebo (-6.2 μV; 95% CI -7.88, -4.51), with a smaller reduction by duloxetine (-4.54 μV; 95% CI -6.21, -2.87) and pregabalin (-3.72 μV; 95% CI -5.40, -2.04), whereas lacosamide was inactive. LEP PtP amplitudes on capsaicin-irritated skin, reflecting peripheral/spinal sensitization, as in neuropathic pain, were reduced by pregabalin (-3.78 μV; 95% CI -5.31, -2.25) and duloxetine (-2.32 μV; 95% CI -3.82, -0.82) but not by celecoxib or lacosamide vs. placebo, which was in agreement with known clinical profiles. Overall, PtP amplitude reductions were in agreement with subjective ratings.

CONCLUSIONS

LEP algesimetry is sensitive to analgesics with different modes of action and may enable the effects of novel analgesics to be assessed during early clinical development.

Gabapentenoids in pain management in urological chronic pelvic pain syndrome: Gabapentin or pregabalin?

AIMS

To compare efficacy of gabapentin and pregabalin in patients with urological chronic pelvic-pain syndrome (UCPPS).

METHODS

Design-retrospective, setting-urology outpatient services of a secondary-care private hospital, inclusion criteria-men 18-50 years, presenting with pelvic pain (lower abdomen, groin, scrotum, perineum, low-back, hip) with or without lower urinary tract symptoms for at least 3 months duration. Hospital database was searched using keywords for neuropathic pain (ICD9-729.2, 719.45) and prostatitis (ICD9-601.1, 601.9). Clinical data were retrieved from patient-records, laboratory and radiology data, and analyzed using SPSS-19 statistical software.

RESULTS

Between Mar 2013 and Oct 2015, data of consecutive 119 patients fulfilling the above criteria was analyzed. Median age of patients was 35 years (IQR 29-43) and median duration of symptoms 12 months (IQR 6-24 months). Before treatment median VAS (0-10) pain score was 5 (IQR 4-6). Gabapentin was significantly more effective in controlling pain compared to pregabalin. Three fourth of patients on gabapentin alone (47/62) reported at least 50% improvement in pain compared to only 40% on pregabalin alone (12/30) (P = 0.0012; χ²  = 9.765. NNT 2.9, 95%CI 1.8-6.5). Twenty patients who were initially put on pregabalin had to switch to gabapentin for lack of efficacy. Forty four percent of patients on pregabalin required amitriptyline (24/54) compared to only 13.6% of those on gabapentin (10/72) required the same (P value of difference 0.0001; χ²  = 14.622. NNT 4, CI 95% 2.2-6.6).

CONCLUSIONS

Gabapentin may be more effective than pregabalin in UCPPS.

Pregabalin in Monitored Anesthesia Care for Ear-nose-throat Surgery

Aim:

The aim of this study was to determine intraoperative sedative and perioperative analgesic requirement and associated side effects of pregabalin (150 mg) for monitored anesthesia care during ear-nose-throat (ENT) surgeries.

Materials and Methods:

The study design was randomized and single-blinded; fifty patients undergoing elective ambulatory ENT surgeries under monitored anesthesia care were randomly allocated to receive either placebo (Group P) or pregabalin (Group PG) 150 mg, orally 1 h before surgery. All patients were then given intravenous (i.v.) midazolam 2 mg and fentanyl 1 μg/kg and local anesthesia at the site. Sedation was induced by administering an i.v. bolus of propofol 0.8 mg/kg and was maintained by continuous infusion of propofol. Level of sedation was assessed by Ramsay scale, and propofol infusion was titrated accordingly. Intraoperative pain was assessed by verbal rating scale (VRS) score. Patient having VRS >4 or complaint of pain was given fentanyl (0.5 μg/kg) i.v. bolus. Intraoperative sedative and analgesic requirement were recorded. Postoperative visual analog scale scores and requirement of analgesics were recorded for the first 24 h after surgery. Diclofenac 75 mg intramuscular (i.m.) was administered as rescue analgesic. Side effects (nausea/vomiting, sedation, dizziness, blurred vision) were also recorded.

Results:

Intraoperative propofol (212 ± 11 mg vs. 174 ± 9 mg; P = 0.013) and fentanyl (120 ± 8 μg vs. 94 ± 6 μg; P = 0.02) consumption was significantly lower in Group PG. Time to first analgesic request was longer (6.1 ± 0.4 h vs. 9.5 ± 1.2 h) with lesser requirement of analgesics (diclofenac) in the postoperative period. Incidence of side effects (sedation, nausea, vomiting) was found to be similar in both the groups.

Conclusion:

Premedication with pregabalin (150 mg) reduces intraoperative sedative and perioperative analgesic requirement in patients undergoing ENT surgeries under monitored anesthesia care with tolerable side effects.

Comparative study between 2 different doses of pregabalin and lidocaine on pain following propofol injection: A double-blind, randomized clinical consort study

BACKGROUND

Propofol, an intravenous anesthetic, often causes pain on injection, which can be very distressful to patients. We investigated the analgesic effect of pregabalin on pain following propofol injection, compared with lidocaine.

METHODS

In a randomized, double-blind, prospective trial, 120 patients were randomized into 3 groups of 40 each; who received oral placebo and intravenous lidocaine 40 mg with venous occlusion for 1 minute (group L, n = 40), oral pregabalin 75 mg and intravenous normal saline with venous occlusion for 1 minute (group LP, n = 40), and oral pregabalin 150 mg and intravenous normal saline with venous occlusion for 1 minute (group HP, n = 40) as pretreatment, followed by administration of 1% propofol 0.5 mg/kg. Pain intensity was measured on a 4-point scale (0 = no, 1 = mild, 2 = moderate, and 3 = severe pain). Any side effects associated with pretreatment substances were recorded during the first 24 hours after surgery.

RESULTS

A total of 120 patients completed this trial. Demographic data were similar between groups. The incidence of pain following propofol injection was significantly reduced in group HP (50%) and group L (55%) compared with group LP (92.5%) (P < 0.05, respectively). The incidences of moderate pain in group HP (12.5%) and group L (15%) were significantly decreased compared with group LP (37.5%; both, P < 0.05). There were no significant differences in the incidence of side effects such as headache and dizziness between groups.

CONCLUSION

Pretreatment with oral pregabalin 150 mg and intravenous lidocaine 40 mg with venous occlusion equally reduced pain from propofol injection.

Preoperative pregabalin prolongs duration of spinal anesthesia and reduces early postoperative pain: A double-blind, randomized clinical CONSORT study

BACKGROUND

The administration of oral pregabalin preoperatively has been reported to reduce acute postoperative pain. However, no clinical study to date has yet fully investigated whether or not pregabalin premedication affects sensory and motor blocks using spinal anesthesia and its effect upon early postoperative pain management. This prospective, randomized, and double-blind clinical study was designed to evaluate the efficacy of a single dose of pregabalin in terms of spinal blockade duration and its potential opioid-sparing effect during the first 24 hours subsequent to urogenital surgery.

METHODS

Forty-four patients scheduled for urogenital surgery under spinal anesthesia were randomly allocated to 2 groups: group C (no premedication; orally administered placebo 2 hours before surgery) and group P (orally administered 150 mg pregabalin 2 hours before surgery).

RESULTS

The duration of sensory and motor blockade was significantly prolonged in group P patients when compared with that in group C patients, and the pain scores at postoperative 6 and 24 hours were significantly lower in group P patients. Requests for analgesics during the first postoperative 24 hours were lower among group P patients.

CONCLUSION

Premedication with a single dose of 150 mg pregabalin before surgery promoted the efficacy of intrathecal bupivacaine and improved postoperative analgesia in patients undergoing urogenital surgery under spinal anesthesia.