Preincisional intravenous low-dose ketamine and local infiltration with ropivacaine reduces postoperative pain after laparoscopic cholecystectomy

Efficacy and Safety of Different Preemptive Analgesia Measures in Pain Management after Laparoscopic Cholecystectomy: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

INTRODUCTION

The purpose of this systematic review and network meta-analysis was to evaluate the efficacy and safety of different preemptive analgesia measures given before laparoscopic cholecystectomy (LC) for postoperative pain in patients.

METHODS

We conducted a comprehensive search in databases including PubMed, Web of Science, Embase, and the Cochrane Library up to March 2024, and collected relevant research data on the 26 preemptive analgesia measures defined in this article in LC surgery. Outcomes included postoperative Visual Analogue Scores (VAS) at different times (2, 6, 12, and 24 h), opioid consumption within 24 h post-operation, time to first rescue analgesia, incidence of postoperative nausea and vomiting (PONV), and incidence of postoperative headache or dizziness.

RESULTS

Forty-nine articles involving 5987 patients were included. The network meta-analysis revealed that multimodal analgesia, nerve blocks, pregabalin, and gabapentin significantly reduced postoperative pain scores at all postoperative time points and postoperative opioid consumption compared to placebo. Tramadol, pregabalin, and gabapentin significantly extended the time to first rescue analgesia. Ibuprofen was the best intervention for reducing PONV incidence. Tramadol significantly reduced the incidence of postoperative headache or dizziness. Subgroup analysis of different doses of pregabalin and gabapentin showed that compared to placebo, pregabalin (300 mg, 150 mg) and gabapentin (600 mg, 300 mg, and 20 mg/kg) were all more effective without significant differences in efficacy between these doses. Higher doses increased the incidence of PONV and postoperative headache and dizziness, with gabapentin 300 mg having a lower adverse drug reaction (ADR) incidence.

CONCLUSIONS

Preemptive analgesia significantly reduced postoperative pain intensity, opioid consumption, extended the time to first rescue analgesia, and decreased the incidence of PONV and postoperative headache and dizziness. Multimodal analgesia, nerve blocks, pregabalin, and gabapentin all showed good efficacy. Gabapentin 300 mg given preoperatively significantly reduced postoperative pain and ADR incidence, recommended for preemptive analgesia in LC.

TRIAL REGISTRATION

PROSPERO CRD42024522185.

Single-shot regional anesthesia for laparoscopic cholecystectomies: a systematic review and network meta-analysis

BACKGROUND

Different regional anesthesia (RA) techniques have been used for laparoscopic cholecystectomy (LC), but there is no consensus on their comparative effectiveness. Our objective was to evaluate the effect of RA techniques on patients undergoing LC using a network meta-analysis approach.

METHODS

We conducted a systematic review and network meta-analysis. We searched PubMed, the Cochrane Central Register of Controlled Trials (CENTRAL), Scopus, and Web of Science (Science and Social Science Citation Index) using the following PICOS criteria: (P) adult patients undergoing LC; (I) any RA single-shot technique with injection of local anesthetics; (C) placebo or no intervention; (O) postoperative opioid consumption expressed as morphine milligram equivalents (MME), rest pain at 12 h and 24 h post-operation, postoperative nausea and vomiting (PONV), length of stay; and (S) randomized controlled trials.

RESULTS

A total of 84 studies were included. With the exception of the rectus sheath block (P = 0.301), the RA techniques were superior to placebo at reducing opioid consumption. Regarding postoperative pain, the transversus abdominis plane (TAP) block (-1.80 on an 11-point pain scale) and erector spinae plane (ESP) block (-1.33 on an 11-point pain scale) were the most effective at 12 and 24 h. The TAP block was also associated with the greatest reduction in PONV.

CONCLUSIONS

RA techniques are effective at reducing intraoperative opioid use, postoperative pain, and PONV in patients undergoing LC. Patients benefit the most from the bilateral paravertebral, ESP, quadratus lumborum, and TAP blocks.

Association of Acute Postoperative Pain and Cigarette Smoking With Cerebrospinal Fluid Levels of Beta-Endorphin and Substance P

Objectives: Cigarette smoking is associated with postoperative pain perception, which might be mediated by beta-endorphin and substance P. These effects on postoperative pain perception have never been investigated in human cerebrospinal fluid (CSF), which reflects biochemical alterations in the brain. Therefore, we investigated the associations among cigarette smoking, postoperative pain, and levels of beta-endorphin and substance P in human CSF. Methods: We recruited 160 Chinese men (80 active smokers and 80 nonsmokers) who underwent lumbar puncture before anterior cruciate ligament reconstruction, and 5-ml CSF samples were collected. Pain visual analog scale (VAS) scores, post-anesthetic recovery duration (PARD), and smoking variables were obtained. CSF levels of beta-endorphin and substance P were measured. Results: Compared to non-smokers, active smokers had significantly higher pain VAS (2.40 ± 0.67 vs. 1.70 ± 0.86, p < 0.001) and PARD scores (9.13 ± 2.11 vs. 7.27 ± 1.35, p = 0.001), lower CSF beta-endorphin (33.76 ± 1.77 vs. 35.66 ± 2.20, p = 0.001) and higher CSF substance P (2,124.46 ± 217.34 vs. 1,817.65 ± 302.14, p < 0.001) levels. Pain VAS scores correlated with PARD in active smokers (r = 0.443, p = 0.001). Conclusions: Cigarette smoking is associated with increased postoperative pain intensity, shown by delayed pain perception, higher pain VAS scores, and lower beta-endorphin and higher substance P levels in the CSF of active smokers. The more extended postoperative pain perception is delayed, the more pain intensity increases.

Perioperative intravenous ketamine for acute postoperative pain in adults

BACKGROUND

Inadequate pain management after surgery increases the risk of postoperative complications and may predispose for chronic postsurgical pain. Perioperative ketamine may enhance conventional analgesics in the acute postoperative setting.

OBJECTIVES

To evaluate the efficacy and safety of perioperative intravenous ketamine in adult patients when used for the treatment or prevention of acute pain following general anaesthesia.

SEARCH METHODS

We searched CENTRAL, MEDLINE and Embase to July 2018 and three trials registers (metaRegister of controlled trials, ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP)) together with reference checking, citation searching and contact with study authors to identify additional studies.

SELECTION CRITERIA

We sought randomised, double-blind, controlled trials of adults undergoing surgery under general anaesthesia and being treated with perioperative intravenous ketamine. Studies compared ketamine with placebo, or compared ketamine plus a basic analgesic, such as morphine or non-steroidal anti-inflammatory drug (NSAID), with a basic analgesic alone.

DATA COLLECTION AND ANALYSIS

Two review authors searched for studies, extracted efficacy and adverse event data, examined issues of study quality and potential bias, and performed analyses. Primary outcomes were opioid consumption and pain intensity at rest and during movement at 24 and 48 hours postoperatively. Secondary outcomes were time to first analgesic request, assessment of postoperative hyperalgesia, central nervous system (CNS) adverse effects, and postoperative nausea and vomiting. We assessed the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

We included 130 studies with 8341 participants. Ketamine was given to 4588 participants and 3753 participants served as controls. Types of surgery included ear, nose or throat surgery, wisdom tooth extraction, thoracotomy, lumbar fusion surgery, microdiscectomy, hip joint replacement surgery, knee joint replacement surgery, anterior cruciate ligament repair, knee arthroscopy, mastectomy, haemorrhoidectomy, abdominal surgery, radical prostatectomy, thyroid surgery, elective caesarean section, and laparoscopic surgery. Racemic ketamine bolus doses were predominantly 0.25 mg to 1 mg, and infusions 2 to 5 µg/kg/minute; 10 studies used only S-ketamine and one only R-ketamine. Risk of bias was generally low or uncertain, except for study size; most had fewer than 50 participants per treatment arm, resulting in high heterogeneity, as expected, for most analyses. We did not stratify the main analysis by type of surgery or any other factor, such as dose or timing of ketamine administration, and used a non-stratified analysis.Perioperative intravenous ketamine reduced postoperative opioid consumption over 24 hours by 8 mg morphine equivalents (95% CI 6 to 9; 19% from 42 mg consumed by participants given placebo, moderate-quality evidence; 65 studies, 4004 participants). Over 48 hours, opioid consumption was 13 mg lower (95% CI 10 to 15; 19% from 67 mg with placebo, moderate-quality evidence; 37 studies, 2449 participants).Perioperative intravenous ketamine reduced pain at rest at 24 hours by 5/100 mm on a visual analogue scale (95% CI 4 to 7; 19% lower from 26/100 mm with placebo, high-quality evidence; 82 studies, 5004 participants), and at 48 hours by 5/100 mm (95% CI 3 to 7; 22% lower from 23/100 mm, high-quality evidence; 49 studies, 2962 participants). Pain during movement was reduced at 24 hours (6/100 mm, 14% lower from 42/100 mm, moderate-quality evidence; 29 studies, 1806 participants), and 48 hours (6/100 mm, 16% lower from 37 mm, low-quality evidence; 23 studies, 1353 participants).Results for primary outcomes were consistent when analysed by pain at rest or on movement, operation type, and timing of administration, or sensitivity to study size and pain intensity. No analysis by dose was possible. There was no difference when nitrous oxide was used. We downgraded the quality of the evidence once if numbers of participants were large but small-study effects were present, or twice if numbers were small and small-study effects likely but testing not possible.Ketamine increased the time for the first postoperative analgesic request by 54 minutes (95% CI 37 to 71 minutes), from a mean of 39 minutes with placebo (moderate-quality evidence; 31 studies, 1678 participants). Ketamine reduced the area of postoperative hyperalgesia by 7 cm² (95% CI -11.9 to -2.2), compared with placebo (very low-quality evidence; 7 studies 333 participants). We downgraded the quality of evidence because of small-study effects or because the number of participants was below 400.CNS adverse events occurred in 52 studies, while 53 studies reported of absence of CNS adverse events. Overall, 187/3614 (5%) participants receiving ketamine and 122/2924 (4%) receiving control treatment experienced an adverse event (RR 1.2, 95% CI 0.95 to 1.4; high-quality evidence; 105 studies, 6538 participants). Ketamine reduced postoperative nausea and vomiting from 27% with placebo to 23% with ketamine (RR 0.88, 95% CI 0.81 to 0.96; the number needed to treat to prevent one episode of postoperative nausea and vomiting with perioperative intravenous ketamine administration was 24 (95% CI 16 to 54; high-quality evidence; 95 studies, 5965 participants).

AUTHORS' CONCLUSIONS

Perioperative intravenous ketamine probably reduces postoperative analgesic consumption and pain intensity. Results were consistent in different operation types or timing of ketamine administration, with larger and smaller studies, and by higher and lower pain intensity. CNS adverse events were little different with ketamine or control. Perioperative intravenous ketamine probably reduces postoperative nausea and vomiting by a small extent, of arguable clinical relevance.

Randomized controlled study of intraincisional infiltration versus intraperitoneal instillation of standardized dose of ropivacaine 0.2% in post-laparoscopic cholecystectomy pain: Do we really need high doses of local anesthetics-time to rethink!

BACKGROUND

Earlier studies done to compare the efficacy of use of local anesthetics at intraperitoneal location versus intraincisional use had utilized equal amount of drugs at the two locations, usually 10-20 ml. Using this large amount of drug in the small space of intraincisional location as compared to similar amount of drug in large intraperitoneal space created an inadvertent bias in favor of patients receiving the drug intraincisionally so these patients naturally experienced less pain.

AIMS AND OBJECTIVES

To conduct a randomized, triple-blind, placebo-controlled study by standardizing dose of local anesthetic, to compare the effectiveness of intraperitoneal against intraincisional use of ropivacaine 0.2% for post-laparoscopic cholecystectomy pain relief.

MATERIALS AND METHODS

294 patients underwent elective 4-port laparoscopic cholecystectomy. Patients were triple blindly randomized. All patients received ~ 23 ml of solution, of which 20 ml was given intraperitoneally (1 ml/cm; 16 ml along right hemi-dome and 4 ml in gall bladder fossa) and ~ 3 ml intraincisionally (1 ml/cm of length of incision). Solution was either normal saline or drug (0.2% ropivacaine) depending on the group [controls (n = 86), intraperitoneal group (n = 100), and intraincisional group (n = 108)]. 5 different pain scales were used for assessment of overall pain. Pain scores were assessed at 5 points of time.

RESULTS

Patients in intraincisional group showed significantly less overall pain and rescue analgesia requirement (p < 0.05). Intraincisional group showed significantly less overall pain (p < 0.05) as compared to intraperitoneal group; however, use of rescue analgesia was comparable in the two groups (p > 0.05); and shoulder pain was significantly less in intraperitoneal group (p < 0.05).

CONCLUSION

The intraincisional use of injection ropivacaine at its minimum concentration of 0.2% in minimal doses of 1 ml/cm at the end of procedure provides significantly more post-operative analgesia as compared to intraperitoneal group and controls. However, for controlling shoulder pain, the use of intraperitoneal ropivacaine is desirable.

Effect of preemptive ketamine administration on postoperative visceral pain after gynecological laparoscopic surgery

The pain following gynecological laparoscopic surgery is less intense than that following open surgery; however, patients often experience visceral pain after the former surgery. The aim of this study was to determine the effects of preemptive ketamine on visceral pain in patients undergoing gynecological laparoscopic surgery. Ninety patients undergoing gynecological laparoscopic surgery were randomly assigned to one of three groups. Group 1 received placebo. Group 2 was intravenously injected with preincisional saline and local infiltration with 20 mL ropivacaine (4 mg/mL) at the end of surgery. Group 3 was intravenously injected with preincisional ketamine (0.3 mg/kg) and local infiltration with 20 mL ropivacaine (4 mg/mL) at the end of surgery. A standard anesthetic was used for all patients, and meperidine was used for postoperative analgesia. The visual analogue scale (VAS) scores for incisional and visceral pain at 2, 6, 12, and 24 h, cumulative analgesic consumption and time until first analgesic medication request, and adverse effects were recorded postoperatively. The VAS scores of visceral pain in group 3 were significantly lower than those in group 2 and group 1 at 2 h and 6 h postoperatively (P<0.05 and P<0.01, respectively). At 2 h and 6 h, the VAS scores of incisional pain did not differ significantly between groups 2 and 3, but they were significantly lower than those in group 1 (P<0.01). Groups 1 and 2 did not show any differences in visceral pain scores at 2 h and 6 h postoperatively. Moreover, the three groups showed no statistically significant differences in visceral and incisional pain scores at 12 h and 24 h postoperatively. The consumption of analgesics was significantly greater in group 1 than in groups 2 and 3, and the time to first request for analgesics was significantly longer in groups 2 and 3 than in group 1, with no statistically significant difference between groups 2 and 3. However, the three groups showed no significant difference in the incidence of shoulder pain or adverse effects. Preemptive ketamine may reduce visceral pain in patients undergoing gynecological laparoscopic surgery.

Evaluation of postoperative pain scores following ultrasound guided transversus abdominis plane block versus local infiltration following day surgery laparoscopic cholecystectomy-retrospective study

Background and Aims:

Postoperative pain for day surgery laparoscopic cholecystectomy has traditionally been managed with the surgeon infiltrating the wound with local anesthetic (LA). However, transversus abdominis plane (TAP) block has recently been used, although its superiority over LA remains uncertain. The primary aim was to compare LA and TAP block pain scores and analgesia used. The secondary aim was to assess satisfaction score and cost.

Material and Methods:

This retrospective study was commenced after ethics committee approval and ANZ clinical trial registry (ACTRN: 12612000737831). The data were collected from the theatre database and medical records of patients presenting for day case laparoscopic cholecystectomy. The sample included patients who received either bilateral port site LA infiltration with 20 ml of 0.25% Bupivacaine or bilateral TAP block with 20 ml of 0.5% ropivacaine and fentanyl postoperative pain protocol. The patients with incomplete medical records were excluded as were those admitted to an inpatient ward. Demographics and clinical characteristics were obtained from the hospital record along with pain score and postsurgery analgesia use. Postoperative pain satisfaction scores were collected by telephonic interview 30-180 days postsurgery.

Results:

Of 51 patients analyzed, 19 were in TAP group 29 in LA group. There were no significant differences between the LA and TAP groups with respect to postoperative pain scores (P = 0.31) or patient satisfaction scores (1 and 2+) (P = 0.36). However, fentanyl consumption in the recovery room was significantly lower in TAP group (P = 0.0079.). The consumables cost were >3 times higher in the TAP when compared to LA group.

Conclusion:

The performance of the TAP block with respect to pain management was comparable to LA. However, LA remains more cost effective.

WITHDRAWN: Perioperative ketamine for acute postoperative pain

This review has been amended to include further information on Menigaux 2000 pre pre and Menigaux 2000 post included studies.

At July 2014, this review is out of date and has been withdrawn. This review is correct as of the date of publication. The latest version is available in the ‘Other versions’ tab on The Cochrane Library, and may still be useful to readers.

The editorial group responsible for this previously published document have withdrawn it from publication.

Preoperative low-dose ketamine has no preemptive analgesic effect in opioid-naïve patients undergoing colon surgery when nitrous oxide is used - a randomized study

BACKGROUND

The analgesic properties of ketamine are associated with its non-competitive antagonism of the N-methyl-D-aspartate receptor; these receptors exhibit an excitatory function on pain transmission and this binding seems to inhibit or reverse the central sensitization of pain. In the literature, the value of this anesthetic for preemptive analgesia in the control of postoperative pain is uncertain. The objective of this study was to ascertain whether preoperative low-dose ketamine reduces postoperative pain and morphine consumption in adults undergoing colon surgery.

METHODS

In a double-blind, randomized trial, 48 patients were studied. Patients in the ketamine group received 0.5 mg/kg intravenous ketamine before surgical incision, while the control group received normal saline. The postoperative analgesia was achieved with a continuous infusion of morphine at 0.015 mg∙kg-¹∙h-¹ with the possibility of 0.02 mg/kg bolus every 10 min. Pain was assessed using the Visual Analog Scale (VAS), morphine consumption, and hemodynamic parameters at 0, 1, 2, 4, 8, 12, 16, and 24 hours postoperatively. We quantified times to rescue analgesic (Paracetamol), adverse effects and patient satisfaction.

RESULTS

No significant differences were observed in VAS scores between groups (P>0.05), except at 4 hours postoperatively (P=0.040). There were no differences in cumulative consumption of morphine at any time point (P>0.05). We found no significant differences in incremental postoperative doses of morphine consumption in bolus, except at 12 h (P =0.013) and 24 h (P =0.002). The time to first required rescue analgesia was 70 ± 15.491 min in the ketamine group and 44 ± 19.494 min in the control (P>0.05). There were no differences in hemodynamic parameters or patient satisfaction (P>0.05).

CONCLUSIONS

Preoperative low-dose-ketamine did not show a preemptive analgesic effect or efficacy as an adjuvant for decreasing opioid requirements for postoperative pain in patients receiving intravenous analgesia with morphine after colon surgery.

Wound infiltration with local anaesthetic agents for laparoscopic cholecystectomy

BACKGROUND

While laparoscopic cholecystectomy is generally considered to be less painful than open surgery, pain is one of the important reasons for delayed discharge after day surgery resulting in overnight stay following laparoscopic cholecystectomy. The safety and effectiveness of local anaesthetic wound infiltration in people undergoing laparoscopic cholecystectomy is not known.

OBJECTIVES

To assess the benefits and harms of local anaesthetic wound infiltration in patients undergoing laparoscopic cholecystectomy and to identify the best method of local anaesthetic wound infiltration with regards to the type of local anaesthetic, dosage, and time of administration of the local anaesthetic.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and Science Citation Index Expanded until February 2013 to identify studies of relevance to this review. We included randomised clinical trials for benefit and quasi-randomised and comparative non-randomised studies for treatment-related harms.

SELECTION CRITERIA

Only randomised clinical trials (irrespective of language, blinding, or publication status) comparing local anaesthetic wound infiltration versus placebo, no intervention, or inactive control during laparoscopic cholecystectomy, trials comparing different local anaesthetic agents for local anaesthetic wound infiltration, and trials comparing the different times of local anaesthetic wound infiltration were considered for the review.

DATA COLLECTION AND ANALYSIS

Two review authors collected the data independently. We analysed the data with both fixed-effect and random-effects meta-analysis models using RevMan. For each outcome, we calculated the risk ratio (RR) or mean difference (MD) with 95% confidence interval (CI).

MAIN RESULTS

Twenty-six trials fulfilled the inclusion criteria of the review. All the 26 trials except one trial of 30 participants were at high risk of bias. Nineteen of the trials with 1263 randomised participants provided data for this review. Ten of the 19 trials compared local anaesthetic wound infiltration versus inactive control. One of the 19 trials compared local anaesthetic wound infiltration with two inactive controls, normal saline and no intervention. Two of the 19 trials had four arms comparing local anaesthetic wound infiltration with inactive controls in the presence and absence of co-interventions to decrease pain after laparoscopic cholecystectomy. Four of the 19 trials had three or more arms that could be included for the comparison of local anaesthetic wound infiltration versus inactive control and different methods of local anaesthetic wound infiltration. The remaining two trials compared different methods of local anaesthetic wound infiltration.Most trials included only low anaesthetic risk people undergoing elective laparoscopic cholecystectomy. Seventeen trials randomised a total of 1095 participants to local anaesthetic wound infiltration (587 participants) versus no local anaesthetic wound infiltration (508 participants). Various anaesthetic agents were used but bupivacaine was the commonest local anaesthetic used. There was no mortality in either group in the seven trials that reported mortality (0/280 (0%) in local anaesthetic infiltration group versus 0/259 (0%) in control group). The effect of local anaesthetic on the proportion of people who developed serious adverse events was imprecise and compatible with increase or no difference in serious adverse events (seven trials; 539 participants; 2/280 (0.8%) in local anaesthetic group versus 1/259 (0.4%) in control; RR 2.00; 95% CI 0.19 to 21.59; very low quality evidence). None of the serious adverse events were related to local anaesthetic wound infiltration. None of the trials reported patient quality of life. The proportion of participants who were discharged as day surgery patients was higher in the local anaesthetic infiltration group than in the no local anaesthetic infiltration group (one trial; 97 participants; 33/50 (66.0%) in the local anaesthetic group versus 20/47 (42.6%) in the control group; RR 1.55; 95% CI 1.05 to 2.28; very low quality evidence). The effect of local anaesthetic on the length of hospital stay was compatible with a decrease, increase, or no difference in the length of hospital stay between the two groups (four trials; 327 participants; MD -0.26 days; 95% CI -0.67 to 0.16; very low quality evidence). The pain scores as measured by the visual analogue scale (0 to 10 cm) were lower in the local anaesthetic infiltration group than the control group at 4 to 8 hours (13 trials; 806 participants; MD -1.33 cm on the VAS; 95% CI -1.54 to -1.12; very low quality evidence) and 9 to 24 hours (12 trials; 756 participants; MD -0.36 cm on the VAS; 95% CI -0.53 to -0.20; very low quality evidence). The effect of local anaesthetic on the time taken to return to normal activity between the two groups was imprecise and compatible with a decrease, increase, or no difference in the time taken to return to normal activity (two trials; 195 participants; MD 0.14 days; 95% CI -0.59 to 0.87; very low quality evidence). None of the trials reported on return to work.Four trials randomised a total of 149 participants to local anaesthetic wound infiltration prior to skin incision (74 participants) versus local anaesthetic wound infiltration at the end of surgery (75 participants). Two trials randomised a total of 176 participants to four different local anaesthetics (bupivacaine, levobupivacaine, ropivacaine, neosaxitoxin). Although there were differences between the groups in some outcomes the changes were not consistent. There was no evidence to support the preference of one local anaesthetic over another or to prefer administration of local anaesthetic at a specific time compared with another.

AUTHORS' CONCLUSIONS

Serious adverse events were rare in studies evaluating local anaesthetic wound infiltration (very low quality evidence). There is very low quality evidence that infiltration reduces pain in low anaesthetic risk people undergoing elective laparoscopic cholecystectomy. However, the clinical importance of this reduction in pain is likely to be small. Further randomised clinical trials at low risk of systematic and random errors are necessary. Such trials should include important clinical outcomes such as quality of life and time to return to work in their assessment.

Addition of ketamine to propofol-alfentanil anesthesia may reduce postoperative pain in laparoscopic cholecystectomy

OBJECTIVE

The aim of this study was to assess whether intravenous anesthesia supplemented with ketamine reduces postoperative pain after elective laparoscopic cholecystectomy.

MATERIALS AND METHODS

Forty patients were enrolled and randomized 1:1 into one of 2 groups: the propofol group (received propofol and alfentanil supplemented with saline) and the ketamine group (received propofol and alfentanil with ketamine). The study was double-blind. The number and amount of the intraoperative additional alfentanil doses were recorded. Pain assessments and cumulative analgesic consumption at postanesthesia care unit (PACU) admission, PACU discharge, postoperative 24th hour, and hospital discharge were recorded.

RESULTS

The visual analog scale scores at PACU admission, PACU discharge, postoperative 24th hour, and hospital discharge were significantly lower in the ketamine group than the propofol group. The pain visual analog scale ≥ 75 at the postoperative 24th hour for the propofol group was also significantly lower (P<0.035) than that of the ketamine group. The difference in analgesic consumption between groups was statistically significant (P<0.001).

CONCLUSIONS

Our study showed that ketamine supplemented with propofol and alfentanil produced better analgesia intraoperatively and postoperatively and decreased analgesic consumption compared with the propofol group after laparoscopic cholecystectomy.

Comparison of ketamine and fentanyl for postoperative pain relief in children following adenotonsillectomy

Adenotonsillectomy has a high incidence of postoperative pain. Therefore, the purpose of this study was to evaluate the effectiveness and safety of either ketamine or fentanyl for postoperative pain relief in children following adenotonsillectomy. Sixty children aged 3-12 years, scheduled for adenotonsillectomy, were enrolled in this randomized, double-blind study. Patients were divided into two groups of 30 cases and received intravenous ketamine (0.5 mg kg(-1)) or fentanyl (1 microg kg(-1)). Modified Hannallah pain scale or Observational Pain Scores (OPS), nausea, vomiting, bleeding, rescue analgesia, sedation and post-anesthesia recovery scores were recorded both at first and 15th minute postoperatively. Moreover, patients receiving ketamine (group 1) or fentanyl (group 2) had comparable OPS and sedation score both on arrival and at 15th minute in the recovery room (p > 0.05). Although rescue analgesics were similarly required in both groups (p > 0.05), the time to reach rescue analgesia was shorter in group 1 (p = 0.001). Only one patient in fentanyl group had nausea and vomiting in the first 15 min that needed antiemetic in the recovery room. In conclusion, intravenous fentanyl (1 microg kg(-1)) compared with intravenous ketamine (0.5 mg kg(-1)) might provide extended time to first analgesic in children undergoing adenotonsillectomy. Interestingly, fentanyl and ketamine did not differ in post-operative vomiting.

Effect of implanting fibrin sealant with ropivacaine on pain after laparoscopic cholecystectomy

AIM: To investigate the safety and efficacy of implanting fibrin sealant with sustained-release ropivacaine in the gallbladder bed for pain after laparoscopic cholecystectomy (LC).

METHODS: Sixty patients (American Society of Anesthesiologists physical status was I or II and underwent LC) were randomly divided into three equal groups: group A (implantation of fibrin sealant in the gallbladder bed), group B (implantation of fibrin sealant carrying ropivacaine in the gallbladder bed), and group C (normal saline in the gallbladder bed). Postoperative pain was evaluated, and pain relief was assessed by visual analog scale (VAS) scoring.

RESULTS: The findings showed that 81.7% of patients had visceral pain, 50% experienced parietal, and 26.7% reported shoulder pain after LC. Visceral pain was significantly less in group B patients than in the other groups (P < 0.05), and only one patient in this group experienced shoulder pain. The mean VAS score in group B patients was lower than that in the other groups.

CONCLUSION: Visceral pain is prominent after LC and can be effectively controlled by implanting fibrin sealant combined with ropivacaine in the gallbladder bed.

The preventative analgesic effect of preincisional peritonsillar infiltration of two low doses of ketamine for postoperative pain relief in children following adenotonsillectomy. A randomized, double-blind, placebo-controlled study

BACKGROUND

In literature, the use of ketamine for the preventative analgesia in the management of postoperative pain is controversial. The purpose of the present study was the clinical assessment of the efficacy of preincisional peritonsillar infiltration of two doses of ketamine on postoperative pain relief compared with peritonsillar saline in children undergoing adenotonsillectomy.

METHODS/MATERIALS

Seventy-five ASA physical status I and II patients, aged 3-12 years, scheduled for adenotonsillectomy were enrolled in this randomized, double-blind, placebo-controlled study. Patients were divided into three groups of 25 each and received a local peritonsillar infiltration of 0.9% saline (group S), ketamine 0.5 mg x kg(-1) (group K1), or ketamine 1 mg x kg(-1) (group K2). All medications were 2 ml in volume which was applied 1 ml per tonsil 3 min prior to tonsillectomy. The Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) and Wilson sedation scale were used to evaluate pain levels and sedative conditions, respectively.

RESULTS

Group S had significantly higher CHEOPS scores than group K1 and K2. Both K1 and K2 groups had comparable scores, which were not statistically significant (P > 0.05). During 24 h after surgery, 16 patients in group S and no patients in groups K1 or K2 needed analgesics (P < 0.001).

CONCLUSIONS

A 0.5 or 1 mg.kg(-1) dose of ketamine given at approximately 3 min before surgery by peritonsillar infiltration provides efficient pain relief during 24 h after surgery without side-effects in children undergoing adenotonsillectomy.

Preincisional and intraperitoneal ropivacaine plus normal saline infusion for postoperative pain relief after laparoscopic cholecystectomy: a randomized double-blind controlled trial

BACKGROUND

A clinical trial was designed to assess the use of preincisional and intraperitoneal ropivacaine, combined or not with normal saline, to reduce pain after laparoscopic cholecystectomy (LC).

METHODS

For this trial, 120 patients were randomly assigned to six groups. For all the patients, preincisional local infiltration of ropivacaine around the trocar wounds was performed. Group A had infusion of ropivacaine at the beginning of the LC. Group B had infusion of ropivacaine at the beginning of the LC plus normal saline infusion at the end. Group C had normal saline infusion and ropivacaine at the end of the LC. Group D had infusion of ropivacaine at the beginning of the LC plus normal saline infusion at the end and a subhepatic closed drain. Group E had ropivacaine at the end of the LC. Group F (control group) had neither ropivacaine nor normal saline infusion. Shoulder tip and abdominal pain were registered at 2, 4, 6, 12, 24, 48, and 72 h postoperatively using a visual analog score (VAS).

RESULTS

Significantly lower pain scores were observed in group B than in group A at 2, 4, 6, 12, and 24 h or in groups C, D, E, and F at 2, 4, 6, 12, 24, and 48 h. Group A also had significantly lower pain scores than groups C, D, E, and F at 2, 4, 6, 12, 24, and 48 h. Requests for analgesics also were significantly less in group B than in group A at 2, 4, 6, 12, and 24 h or in groups C, D, and E at 2, 4, 6, 12, 24, and 48 h. Demand for additional analgesia was less in group B than in groups A, C, D, E, and F at 2, 4, 6, 12, and 24 h and in group A than in groups C, D, E, and F at 2, 4, 6, and 12 h.

CONCLUSION

Preincisional local infiltration plus intraperitoneal infusion of ropivacaine at the beginning of LC combined with normal saline infusion at the end of the procedure is a safe and valid method for reducing pain after LC.

Prospective, Double-Blinded, Randomized, Placebo-Controlled Comparison of Local Anesthetic and Nonsteroidal Anti-Inflammatory Drugs for Postoperative Pain Management after Laparoscopic Surgery

Compared with the open approach, laparoscopy has been shown to significantly reduce postoperative pain. Improving postoperative analgesia in laparoscopic surgery is an area of continued interest. The goal of this study was to compare the efficacy of local anesthetic infiltration with or without preoperative nonsteroidal anti-inflammatory drugs. Patients undergoing elective laparoscopic cholecystectomy were enrolled in an Institutional Review Board-approved, prospective, double-blinded, randomized, placebo-controlled comparison study. Patients were randomized into four groups: Group I, preoperative oral administration of a placebo medication and prein cision local infiltration of 40 mL of 0.5 per cent bupivicaine at trocar sites; Group II, preoperative oral administration of 50 mg of rofecoxib; Group III, preoperative oral administration of 50 mg of rofecoxib and preincision local infiltration of 40 mL of 0.5 per cent bupivicaine into skin, muscle, and peritoneum; and Group IV, preoperative oral administration of a placebo medication. Postoperative pain scores were assessed at 4 hours, 8 hours, 12 hours, and 24 hours using a visual analog scale. Postoperative analgesic use, complications, and length of stay were recorded. Statistical significance was defined as P < 0.05. Fifty-five patients (46 women and 9 men) were enrolled in this study and underwent a standardized, elective, laparoscopic cholecystectomy for mild, symptomatic cholelithiasis (96.4%) and gallbladder polyps (3.6%). No patient had pain immediately before surgery. Postoperative analgesic requests, visual analog scale results, incidence of postoperative vomiting at 4 hours, 8 hours, 12 hours, and 24 hours, in addition to length of stay, were not statistically different between the four groups. No complications occurred. The use of preoperative rofecoxib, 0.5 per cent bupivicaine infiltration, or both for postoperative analgesia did not decrease postoperative pain or decrease length of stay after laparoscopic cholecystectomy compared with placebo. Preoperative administration of an oral anti-inflammatory pain medication, infiltration of a local anesthetic, or both had no greater effect than placebo in controlling discomfort after a laparoscopic cholecystectomy. The challenge of preempting postoperative pain continues and will require further investigation.

Perioperative ketamine for acute postoperative pain

BACKGROUND

Postoperative pain management is often limited by adverse effects such as nausea and vomiting. Adjuvant treatment with an inexpensive opioid-sparing drug such as ketamine may be of value in giving better analgesia with fewer adverse effects.

OBJECTIVES

To evaluate the effectiveness and tolerability of ketamine administered perioperatively in the treatment of acute postoperative pain in adults.

SEARCH STRATEGY

Studies were identified from MEDLINE (1966-2004), EMBASE (1980-2004), the Cochrane Library (2004) and by handsearching reference lists from review articles and trials. The manufacturer of ketamine (Pfizer) provided search results from their in-house database, PARDLARS.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of adult patients undergoing surgery, being treated with perioperative ketamine or placebo. Studies where ketamine was administered in addition to a basic analgesic (such as morphine or NSAID) in one study group, and compared with a group receiving the same basic analgesic (but without ketamine) in another group, were also included.

DATA COLLECTION AND ANALYSIS

Two independent reviewers identified fifty five RCTs for potential inclusion. Quality and validity assessment was performed by two independent reviewers. In the case of discrepancy, a third reviewer was consulted. Patient reported pain intensity and pain relief was assessed using visual analogue scales or verbal rating scales and adverse effects data were collated.

MAIN RESULTS

Thirty-seven trials were included (2240 participants). Eighteen trials were excluded.Twenty-seven of the 37 trials found that perioperative subanaesthetic doses of ketamine reduced rescue analgesic requirements or pain intensity, or both. Quantitative analysis showed that treatment with ketamine reduced 24 hour PCA morphine consumption and postoperative nausea or vomiting (PONV). Adverse effects were mild or absent.

AUTHORS' CONCLUSIONS

Ketamine in subanaesthetic dose (that is a dose which is below that required to produce anaesthesia) is effective in reducing morphine requirements in the first 24 hours after surgery. Ketamine also reduces postoperative nausea and vomiting. Adverse effects are mild or absent.

Peri-operative ketamine for acute post-operative pain: a quantitative and qualitative systematic review (Cochrane review)

BACKGROUND

Post-operative pain management is usually limited by adverse effects such as nausea and vomiting. Adjuvant treatment with an inexpensive opioid-sparing drug such as ketamine may be of value in giving better analgesia with fewer adverse effects. The objective of this systematic review was to evaluate the effectiveness and tolerability of ketamine administered peri-operatively in the treatment of acute post-operative pain in adults.

METHODS

Studies were identified from MEDLINE (1966-2004), EMBASE (1980-2004), the Cochrane Library (2004) and by hand searching reference lists from review articles and trials. The manufacturer of ketamine (Pfizer AS, Lysaker, Norway) provided search results from their in-house database, PARDLARS. Randomized and controlled trials (RCTs) of adult patients undergoing surgery, being treated with peri-operative ketamine, placebo or an active control were considered for inclusion.

RESULTS

Eighteen trials were excluded. Thirty-seven trials were included. Twenty-seven out of 37 trials found that peri-operative ketamine reduced rescue analgesic requirements or pain intensity, or both. Quantitative analysis showed that treatment with ketamine reduced 24-h patient-controlled analgesia (PCA) morphine consumption and post-operative nausea and vomiting (PONV). Adverse effects were mild or absent.

CONCLUSION

In the first 24 h after surgery, ketamine reduces morphine requirements. Ketamine also reduces PONV. Adverse effects are mild or absent. These data should be interpreted with caution as the retrieved studies were heterogenous and the result of the meta-analysis can not be translated into any specific administration regimen with ketamine.

Kétamine à faibles doses : antihyperalgésique, non analgésique

Recent data in animal experiments as in clinical trials have clearly reported that pain modulation is related to an equilibrium between antinociceptive and pronociceptive systems. Therefore, the apparent pain level could not only be a consequence of a nociceptive input increase but could also result from a pain sensitization process. Glutamate, via NMDA receptors, plays a major role in the development of such a neuronal plasticity in the central nervous system, leading to a pain hypersensitivity that could facilitate chronic pain development. By an action on NMDA receptors opioids also induce, in a dose dependent manner, an enhancement of this postoperative hypersensitivity. "Antihyperalgesic" doses of ketamine, an NMDA receptor antagonist, were able to decrease this central sensitization not only in painful animal but also in human volunteers exposed to different pain models, or in the postoperative period. Many studies have reported that ketamine effects are elicited when this drug is administered the following manner: peroperative bolus (0.1 to 0.5 mg/kg), followed by a constant infusion rate (1 to 2 microg/kg per min) during the peroperative period and for 48 to 72 hours after anaesthesia. Those ketamine doses improved postoperative pain management by reducing hyperalgesia due to both surgical trauma and high peroperative opioid doses. This antihyperalgesic action of ketamine also limited the postoperative morphine tolerance leading to a decrease in analgesic consumption and an increase in the analgesia quality.

A procedure-specific systematic review and consensus recommendations for postoperative analgesia following laparoscopic cholecystectomy

BACKGROUND

Laparoscopic cholecystectomy has advantages over the open procedure for postoperative pain. However, a systematic review of postoperative pain management in this procedure has not been conducted.

METHODS

A systematic review was conducted according to the guidelines of the Cochrane Collaboration. Randomized studies examining the effect of medical or surgical interventions on linear pain scores in patients undergoing laparoscopic cholecystectomy were included. Qualitative and quantitative analyses were performed. Recommendations for patient care were derived from review of these data, evidence from other relevant procedures, and clinical practice observations collated by the Delphi method among the authors.

RESULTS

Sixty-nine randomized trials were included and 77 reports were excluded. Recommendations are provided for preoperative analgesia, anesthetic and operative techniques, and intraoperative and postoperative analgesia.

CONCLUSIONS

A step-up approach to the management of postoperative pain following laparoscopic cholecystectomy is recommended. This approach has been designed to provide adequate analgesia while minimizing exposure to adverse events.

Local anaesthesia for pain relief after laparoscopic cholecystectomy—a systematic review

Local anaesthetics (LA) are increasingly being used intraoperatively for the prevention of postoperative pain. The efficacy of local anaesthetic infiltration into incision sites has only been shown in patients undergoing inguinal herniorrhaphy. However, in one meta-analysis of the literature, intraperitoneal LA have been shown to be effective for pain relief following laparoscopic cholecystectomy (LC). The present review of the literature was done to summarise current knowledge on the effects of LA following LC. The Medline database was searched via PubMed to identify relevant randomised clinical trials in patients undergoing LC and where LA was used for pain management. The literature was restricted to adults (> 19 years) and humans. Abstracts of all articles were searched to determine if the trial was a comparison between LA and placebo injected intraperitoneally or infiltrated locally, with relevant postoperative data on pain scores, analgesic consumption and side effects. A total of 31 relevant studies were identified from which data could be extracted. Postoperative pain, in general, was mild to moderate after LC, worst at the incision site or intra-abdominally. Five of six studies in which LA were injected locally found beneficial effects on postoperative pain but not analgesic consumption for up to 24 hours postoperatively. When injected intraperitoneally, 14 of 23 studies found a reduction in pain scores in the LA group but only 9 of 21 found a reduction in analgesic consumption. A meta-analysis of only three studies with extractable data found no difference in abdominal pain during 0-24 hours between the LA and placebo groups. Side effects were few but some studies reported toxic plasma concentrations of LA in some patients, although no symptoms of LA toxicity were seen in these patients. In conclusion, LA have some beneficial effects when infiltrated locally and intraperitoneally. Although side effects are rare, the dose of LA should be monitored closely to avoid toxicity. Future studies should be directed towards determining whether the analgesic effects of LA are via peripheral mechanisms or systemic absorption. The explanation for the wide interindividual variation in pain following LC should also be better investigated.

Ketamine and postoperative pain – a quantitative systematic review of randomised trials

Ketamine, an N-methyl-D-aspartate receptor antagonist, is known to be analgesic and to induce psychomimetic effects. Benefits and risks of ketamine for the control of postoperative pain are not well understood. We systematically searched for randomised comparisons of ketamine with inactive controls in surgical patients, reporting on pain outcomes, opioid sparing, and adverse effects. Data were combined using a fixed effect model. Fifty-three trials (2839 patients) from 25 countries reported on a large variety of different ketamine regimens and surgical settings. Sixteen studies tested prophylactic intravenous ketamine (median dose 0.4 mg/kg, range (0.1-1.6)) in 850 adults. Weighted mean difference (WMD) for postoperative pain intensity (0-10 cm visual analogue scale) was -0.89 cm at 6 h, -0.42 at 12 h, -0.35 at 24 h and -0.27 at 48 h. Cumulative morphine consumption at 24 h was significantly decreased with ketamine (WMD -15.7 mg). There was no difference in morphine-related adverse effects. The other 37 trials tested in adults or children, prophylactic or therapeutic ketamine orally, intramuscularly, subcutaneously, intra-articulary, caudally, epidurally, transdermally, peripherally or added to a PCA device; meta-analyses were deemed inappropriate. The highest risk of hallucinations was in awake or sedated patients receiving ketamine without benzodiazepine; compared with controls, the odds ratio (OR) was 2.32 (95%CI, 1.09-4.92), number-needed-to-harm (NNH) 21. In patients undergoing general anaesthesia, the incidence of hallucinations was low and independent of benzodiazepine premedication; OR 1.49 (95%CI 0.18-12.6), NNH 286. Despite many published randomised trials, the role of ketamine, as a component of perioperative analgesia, remains unclear.

A Qualitative Systematic Review of the Role of N-Methyl-d-Aspartate Receptor Antagonists in Preventive Analgesia

We evaluated in a qualitative systematic review the effect of N-methyl-D-aspartate (NMDA) receptor antagonists on reducing postoperative pain and analgesic consumption beyond the clinical duration of action of the target drug (preventive analgesia). Randomized trials examining the use of an NMDA antagonist in the perioperative period were sought by using a MEDLINE (1966-2003) and EMBASE (1985-2003) search. Reference sections of relevant articles were reviewed, and additional articles were obtained if they evaluated postoperative analgesia after the administration of NMDA antagonists. The primary outcome was a reduction in pain, analgesic consumption, or both in a time period beyond five half-lives of the drug under examination. Secondary outcomes included time to first analgesic request and adverse effects. Forty articles met the inclusion criteria (24 ketamine, 12 dextromethorphan, and 4 magnesium). The evidence in favor of preventive analgesia was strongest in the case of dextromethorphan and ketamine, with 67% and 58%, respectively, of studies demonstrating a reduction in pain, analgesic consumption, or both beyond the clinical duration of action of the drug concerned. None of the four studies examining magnesium demonstrated preventive analgesia.

IMPLICATIONS

We evaluated, in a qualitative systematic review, the effect of N-methyl D-aspartate antagonists on reducing postoperative pain and analgesic consumption beyond the clinical duration of action of the target drug (preventive analgesia). Dextromethorphan and ketamine were found to have significant immediate and preventive analgesic benefit in 67% and 58% of studies, respectively.

Current status of pre-emptive analgesia

PURPOSE OF REVIEW

The controversy over preemptive analgesia continues unabated, with studies both supporting and refuting its efficacy. The timing of an analgesic intervention and presence of a placebo control may have significant impact on the interpretation of results and may have led to the premature conclusion that preemptive analgesia is of limited clinical utility. A review of the recent literature using strict definitions of preemptive and preventive analgesia is required in order to clarify the broader issue of the benefits of perioperative analgesia.

RECENT FINDINGS

A total of 27 studies, published from April 2001 to April 2002, were found to evaluate preemptive (n = 12) or preventive analgesia (n = 15). Evidence for a benefit of preventive analgesia was strong, with 60% of studies finding reduced pain or analgesic consumption beyond the clinical duration of action of the analgesic intervention. Evidence for a benefit of preemptive analgesia was equivocal, with 41.7% of studies demonstrating that preincisional treatment reduces pain or analgesic consumption to a greater extent than does postincisional treatment.

SUMMARY

Studies that used a preventive design had a greater likelihood of finding a beneficial effect. The application of preventive perioperative analgesia (not necessarily preincisional) is associated with a significant reduction in pain beyond the clinical duration of action of the analgesic agent, in particular for the N-methyl-D-aspartate antagonists. The classical definition of preemptive analgesia should be abandoned in favor of preventive analgesia. This will broaden the scope of inquiry from a narrow focus on preincisional versus postincisional interventions to one that aims to minimize postoperative pain and analgesic requirements by reducing peripheral and central sensitization arising from noxious preoperative, intraoperative and postoperative inputs.