Gabapentin for acute and chronic post-surgical pain

Pain after surgery remains a significant clinical problem as it impairs recovery adversely and may lead to the transition to chronic pain. Opioid medications are far from ideal agents in suppressing postoperative pain. Gabapentin -an anticonvulsant with antihyperalgesic properties- originally efficacious against neuropathic pain seems to be very promising for the management of pain after surgery as well. Gabapentin, by decreasing noxious stimulus-induced excitatory neurotransmitter release at the spinal cord, may attenuate central sensitization, and eventually decrease postoperative late pain. Furthermore, different sites of action may be pertinent to a synergistic effect with opioids. Both actions (antihyperalgesic effect and synergy with opioid analgesia) may manifest as analgesia and/or opioid-sparing effect after surgery. This has been confirmed by a variety of clinical studies, in a variety of settings. Most of these studies have shown that either single preoperative or repeated doses of gabapentin, continued for up to a few days after surgery, decrease acute postoperative pain and/or need for postoperative opioids. This has been shown for procedures such as abdominal and vaginal hysterectomy, breast surgery for cancer (mastectomy or lumpectomy), lumbar discectomy and spinal fusion, laparoscopic cholecystectomy and other, such as ENT surgery. Finally, a few studies indicate that perioperative gabapentin may as well decrease chronic pain several weeks after surgery

Sciatic lateral popliteal block with clonidine alone or clonidine plus 0.2% ropivacaine: effect on the intra-and postoperative analgesia for lower extremity surgery in children: a randomized prospective controlled study

<p>Abstract</p> <p>Background</p> <p>The effect of adding clonidine to local anesthetics for nerve or plexus blocks remains unclear. Most of the studies in adults have demonstrated the positive effects of clonidine on intra- and postoperative analgesia when used as an adjunctive agent or in some cases as a single to regional techniques. In the pediatric population, there are only few trials involving clonidine as an adjunct to regional anesthesia, and the analgesic benefits are not definite in this group of patients. The evidence concerning perineural administration of clonidine is so far inconclusive in children, as different types and volume of local anesthetic agents have been used in these studies. Moreover, the efficacy of regional anesthesia is largely affected by the operator's technique, accuracy and severity of operation.</p> <p>Methods</p> <p>The use of clonidine alone or combined with 0.2% ropivacaine for effective analgesia after mild to moderate painful foot surgery was assessed in 66 children, after combined sciatic lateral popliteal block (SLPB) plus femoral block. The patients were randomly assigned into three groups to receive placebo, clonidine, and clonidine plus ropivacaine. Time to first analgesic request in the groups was analyzed by using Kaplan-Meier and the log-rank test (mean time, median time, 95% CI).</p> <p>Results</p> <p>In our study, clonidine administered alone in the SLPB seems promising, maintaining intraoperatively the hemodynamic parameters SAP, DAP, HR to the lower normal values so that no patient needed nalbuphine under 0.6 MAC sevoflurane anesthesia, and postoperatively without analgesic request for a median time of 6 hours. In addition, clonidine administered as adjuvant enhances ropivacaine's analgesic effect for the first postoperative day in the majority of children (p = 0.001). Clonidine and clonidine plus ropivacaine groups also didn’t demonstrate PONV, motor blockade, and moreover, the parents of children expressed their satisfaction with the excellent perioperative management of their children, with satisfaction score 9.74 ± 0.45 and 9.73 ± 0.70 respectively. On the contrary all the patients in the control group required rescue nalbuphine in the recovery room, and postoperatively, along with high incidence of PONV, and the parents of children reported a low satisfaction score (7.50 ± 0.70).</p> <p>Conclusions</p> <p>Clonidine appears promising more as an adjuvant in 0.2% ropivacaine and less than alone in the SLPB plus femoral block in children undergoing mild to moderate painful foot surgery, with no side effects.</p> <p>Trial registration</p> <p>ClinicalTrials.gov, <a href="http://www.controlled-trials.com/ISRCTN90832436">ISRCTN90832436</a>, (ref: CCT-NAPN-20886).</p

Systemic Opioids Enhance the Spread of Sensory Analgesia Produced by Intrathecal Lidocaine

The effect of different doses of fentanyl and nalbuphine on the spread of spinal analgesia produced by lidocaine was studied in 68 patients undergoing transurethral resection of the prostate (TURP) under spinal anesthesia. Patients were randomly assigned to six groupsfentanyl A, B, or C (FA, FB, FC) or nalbuphine A, B, or C (NA, NB, NC), which received intravenous (IV) 50, 100, or 150 μg of fentanyl or 10, 15, or 20 mg of nalbuphine, respectively, 20 min after spinal anesthesia with lidocaine. We tested the level of spinal analgesia with pinprick sensation 20 min after spinal anesthesia and 10 min after the opioid administration, when 0.4 mg of naloxone was administered IV. The levels of sensory analgesia were reassessed 10 min after naloxone. Ten minutes after fentanyl or nalbuphine, the level of analgesia increased (1.8 ± 1.7, 3.1 ± 1.2, and 4.1 ± 1.5 cm, in the FA, FB, and FC groups and 1.9 ± 0.9, 2.6 ± 1.4, and 3.7 ± 2.2 cm in the NA, NB, and NC groups, respectively). The increases in the level of analgesia differed significantly between the fentanyl groups (F = 8.0939; df = 2,35; P < 0.001), the increase produced by 150 μg being significantly higher than produced by 50 μg of fentanyl (limits of confidence −4.236809 and −0.4431909; P < 0.01). Naloxone reversed the effect of fentanyl and 10 min after its administration the fentanyl groups did not differ with regard to the level of spinal analgesia. Nalbuphine also enhanced the spread of sensory analgesia produced by lidocaine, but the nalbuphine groups did not differ significantly between them with regard to the level of analgesia 10 min after its administration as well 10 min after naloxone treatment. Naloxone completely antagonized the effect of fentanyl on spinal analgesia but only partially the effect of nalbuphine. Fentanyl 100 and 150 μg significantly increased the level of analgesia when compared with equipotent doses of nalbuphine 10 and 15 mg (P < 0.02 and P < 0.05, respectively). We conclude that systemic fentanyl and nalbuphine enhance the spread of spinal analgesia in a dose-dependent manner. This effect is antagonized by naloxone, and may be clinically important when a spinal block dissipates before completion of surgery

Pretreatment with nitrous oxide enhances induction of anesthesia with sevoflurane: A randomized controlled trial

Background: Inhalation anesthesia with sevoflurane may be enhanced by several drugs or techniques. The aim of the present study was to investigate the effect of nitrous oxide (N2O) pretreatment on the speed of anesthesia induction with sevoflurane. Materials and Methods: Eighty patients scheduled for hysteroscopy under general anesthesia were randomly assigned to inhale for 10 min before induction 50% N2O in oxygen or air via a facemask. Anesthesia was induced with 7-8% sevoflurane in oxygen via a facemask. Bispectral index (BIS), end-tidal carbon dioxide (EtCO2) tidal volume, respiratory rate, oxygen saturation (SpO2), and heart rate were recorded every minute during the 10 min pretreatment periods and every 30 s during the first 300 s of induction with sevoflurane. During induction of anesthesia inspired and end-tidal sevoflurane concentrations were also recorded. Results: During the 10 min of inspired 50% N2O or air BIS, EtCO2, tidal volume, respiratory rate and heart rate values did not differ between the two groups except for the SpO2, which was higher in the N2O group (P <0.001). During induction of anesthesia the N2O group exhibited lower BIS values (P = 0.001), being significant at 60-150 s (P <0.001, P <0.001, P = 0.002, P = 0.014) as well as at 270 s (P = 0.004). EtCO2and tidal volume were consistently lower in the N2O group (P = 0.001, P = 0.041 respectively) and respiratory rate was higher (P = 0.007). Conclusion: Our results show that pretreatment of the patients with 50% N2O for 10 min enhances the speed of induction with sevoflurane as assessed by the BIS monitoring

Multimodal analgesia with gabapentin and local anesthetics prevents acute and chronic pain after breast surgery for cancer

We evaluated the effect of multimodal analgesia on acute and chronic pain after breast surgery for cancer. Fifty patients scheduled for breast cancer surgery were blindly randomized to receive gabapentin, eutectic mixture of local anesthetics cream, and ropivacaine in the wound or three placebos. Pain (visual analog scale) and analgesics were recorded in the postanesthesia care unit (PACU) 3, 6, and 9 h and 8 days after surgery. Three and 6 mo later, patients were assessed for chronic pain. The treatment group consumed less paracetamol in the PACU (469 versus 991 mg; P < 0.002) and less Lonalgal (1.0 versus 4.4 tablets; P = 0.003) than the controls, exhibited lower visual analog scale scores at rest in the PACU (P = 0.001) and on postoperative Days 1, 3, and 5 (P = 0.040, P = 0.015, and P = 0.045, respectively), and after movement in the PACU (P = 0.001) and on postoperative Days 2, 4, and 8 (P = 0.028, P = 0.007, and P = 0.032, respectively). Three and 6 mo after surgery, 18 of 22 (82%) and 12 of 21 (57%) of the controls reported chronic pain versus 10 of 22 (45%) and 6 of 20 (30%) in the treatment group (P = 0.028 and P = 0.424, respectively); 5 of 22 and 4 of 21 of the controls required analgesics versus 0 of 22 and 0 of 20 of those treated (P = 0.048 and P = 0.107, respectively). Multimodal analgesia reduced acute and chronic pain after breast surgery for cancer

Physiological and operative severity score for the enumeration of mortality and morbidity scoring systems for assessment of patient outcome and impact of surgeons' and anesthesiologists' performance in hepatopancreaticobiliary surgery

Context: The physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM) is a scoring system used to predict morbidity and mortality. Aims: We compared the physiological and operative risk, the expected morbidity and mortality, and the observed postoperative mortality among patients operated by different surgeons and anesthetized by different anesthesiologists. Settings and Design: This was a retrospective, single center study. Subjects and Methods: The anesthetic records of 159 patients who underwent hepatopancreaticobiliary surgery were analyzed for the physiological and operative severity, POSSUM morbidity, POSSUM and Portsmouth POSSUM (P-POSSUM) mortality scoring systems, observed mortality in 30-days, 3, 6, and 12 months postoperatively, duration of surgery, and units of packed red blood cells (PRBC) transfused. These variables were compared among patients operated by five different surgeons and anesthetized by seven different anesthesiologists. Statistical Analysis: One-way analysis of variance was used for normally and Kruskal–Wallis test for nonnormally distributed responses. Differences in percentages of postoperative mortality were assessed by Chi-squared test. Results: The physiological severity, POSSUM morbidity, POSSUM and P-POSSUM mortality scores, and observed mortality at 1, 3, 6, and 12 months postoperatively did not differ among patients operated by different surgeons and anesthetized by different anesthesiologists. Duration of surgery (P < 0.001), PRBC units transfused (P = 0.002), and operative severity (P = 0.001) differed significantly among patients operated by different surgeons. Conclusions: The physiological severity score, POSSUM and P-POSSUM scores did not differ among patients operated by different surgeons and anesthetized by different anesthesiologists. The different operative severity scores did not influence the observed mortality in the postoperative period