Comparison of effects of intraoperative nefopam and ketamine infusion on managing postoperative pain after laparoscopic cholecystectomy administered remifentanil

Opioid-sparing anesthesia and patient-reported outcomes after open gynecologic surgery: a historical cohort study

PURPOSE

Dexmedetomidine and ketamine may be administered intraoperatively as continuous infusions to provide opioid-sparing anesthesia. Recent evidence has yielded controversial results regarding the impact of opioid-free anesthesia on postoperative complications, and there is a gap in knowledge regarding patient-reported outcomes (PROs). This study aimed to determine the impact of opioid-sparing anesthesia and opioid-based anesthesia on PROs among gynecologic patients within an enhanced recovery after surgery (ERAS) program.

METHODS

We formed a single-center historical cohort from patients enrolled in another study who underwent open gynecologic surgery on an ERAS program from November 2014 to December 2020 (n = 2,095). We identified two cohorts based on the type of balanced anesthesia administered: 1) opioid-sparing anesthesia defined as the continuous infusion of dexmedetomidine and ketamine (adjuvants) during surgery or 2) opioid-based anesthesia (no adjuvants). We measured the quality of postoperative recovery using the MD Anderson Symptom Inventory (MDASI), a 29-item validated tool that was administered preoperatively, daily while admitted, and weekly after discharge until week 6. The primary outcome was interference with walking. We matched both cohorts and used a multilevel linear mixed-effect model to evaluate the effect of opioid-sparing anesthesia on the primary outcome.

RESULTS

In total, 498 patients were eligible (159 in the opioid-sparing anesthesia cohort and 339 in the opioid-based anesthesia cohort), of whom 149 matched pairs were included in the final analysis. Longitudinal assessment showed no significant or clinically important difference in interference with walking (P = 0.99), general activity (P = 0.99), or other PROs between cohorts. Median [interquartile range (IQR)] intraoperative opioid administration (expressed as morphine milligram equivalents [MME]) among matched patients in the opioid-sparing anesthesia cohort was 30 [25-55] mg vs 58 [8-70] mg in the opioid-based anesthesia cohort (P < 0.01). Patients in the opioid-sparing anesthesia cohort had a lower opioid consumption in the postanesthesia care unit than those in the opioid-based anesthesia cohort (MME, 3 [0-10] mg vs 5 [0-15] mg; P < 0.01), but there was no significant difference between cohorts in total postoperative opioid consumption (MME, 23 [0-94] mg vs 35 [13-95] mg P = 0.053).

CONCLUSIONS

In this single-center historical cohort study, opioid-sparing anesthesia had no significant or clinically important effects on interference with walking or other PROs in patients undergoing gynecologic surgery compared with opioid-based anesthesia. Opioid-sparing anesthesia was associated with less short-term opioid consumption than opioid-based anesthesia.

The Comparison of Postoperative Pain, Nausea, and Vomiting between Veress Needle Entry and Direct Trocar Entry Methods in Patients Undergoing Laparoscopic Cholecystectomy

BACKGROUND

Postoperative pain, nausea, and vomiting are the most common side effects of laparoscopic cholecystectomy (LC). In the present study, we investigated the differences in postoperative pain, nausea, and vomiting between Veress needle and direct trocar entry methods among patients undergoing LC.

METHODS

96 patients with gallstones were studied. They were randomly divided into two groups: the patients in the first group (n = 48) were insufflated 8.1 liters per minute CO₂ gas by direct trocar port, and the patients in another group (n = 48) were insufflated 2.1 liters per minute CO₂ gas by Veress needle. Pain intensity, nausea, and vomiting were assessed at 20 minutes, 4 hours, and 12 hours after the operations.

RESULTS

The duration of CO₂ gas insufflation in Veress needle was 88.7 ± 10.7 seconds and indirect trocar was 16.6 ± 1.6 seconds. Visual analog scale (VAS) score significantly reduced in Veress needle compared with direct trocar (0.39 ± 0.98 vs. 1.68 ± 1.48) at 20 min after the operation, while there was no difference at 4 hours and 12 hours after the operation. The requirement and dose of pethidine injection were significantly lower in Veress needle than direct trocar. In addition, nausea and vomiting occurred in Veress needle less than direct trocar at 20 min, 4 hours, and 12 hours after LC.

CONCLUSION

Pain intensity just in the short term after LC in the group with CO₂ gas insufflation in Veress needle was significantly less than the other group, while nausea and vomiting were significantly less during the whole follow-up periods in the group with CO₂ gas insufflation in Veress needle.

An Analysis of Prolonged, Continuous Ketamine Infusions

INTRODUCTION

Opioids carry high risk of dependence, and patients can rapidly build tolerance after repetitive dosing. Low-dose ketamine is an analgesic agent alternative that provides more hemodynamic stability. We sought to describe the effects of prolonged ketamine use in non-burn patients.

MATERIALS AND METHODS

We queried the electronic health system at the Brooke Army Medical Center for patient encounters with ketamine infusions lasting >72 hours. We abstracted data describing demographics, vital signs, ketamine infusion dose and duration, and discharge diagnoses potentially relevant to ketamine side effects.

RESULTS

We identified 194 subjects who met the study inclusion criteria. The median age was 39 years, most were male (67.0%), and most were primarily admitted for a non-trauma reason (59.2%). The mean ketamine drip strength was 43.9 mg/h (95% CI, 36.7-51.1; range 0.1-341.6) and the mean drip length was 130.8 hours (95% CI, 120.3-141.2; range 71-493). Most subjects underwent mechanical ventilation (56.1%) at some point during the infusion and most survived to hospital discharge (83.5%). On a per-day basis, the average heart rate was 93 beats per minute, systolic blood pressure was 128 mmHg, diastolic blood pressure was 71 mmHg, oxygen saturation was 96%, and respiratory rate was 22 respirations per minute.

CONCLUSIONS

We demonstrate that continuous ketamine infusions provide a useful adjunct for analgesia and/or sedation. Further development of this adjunct modality may serve as an alternative agent to opioids.

Analgesic Efficacy of Nefopam as an Adjuvant in Patient-Controlled Analgesia for Acute Postoperative Pain After Laparoscopic Colorectal Cancer Surgery

Despite rapid advancements in laparoscopic surgical techniques and perioperative management, postoperative pain remains a significant clinical issue. We examined the analgesic efficacy of nefopam as an adjuvant in patient-controlled analgesia (PCA) for acute postoperative pain in patients undergoing laparoscopic colorectal cancer surgery. We retrospectively analyzed the medical records of 120 patients who did or did not receive 80 mg of nefopam as an adjuvant in fentanyl PCA; they were allocated to the nefopam (n = 60) or non-nefopam group (n = 60). The demographic, clinical, and anesthetic data, with data on pain severity and opioid administration at the postoperative anesthesia care unit (PACU) on postoperative days (PODs) 1, 3, and 5, were compared between the groups. The pain score and opioid administration did not differ at the PACU or on PODs 1, 3, or 5. The day of PCA discontinuation, time to pass flatus, length of the hospital stay, and incidence of nausea/vomiting, dizziness, and headache also did not differ between the groups. Fentanyl PCA with 80 mg of nefopam as an adjuvant did not have a superior analgesic effect after laparoscopic colorectal cancer surgery.

Analgesic efficacy of intravenous nefopam after spine surgery: a randomized, double-blind, placebo-controlled trial

Background: The incidence of moderate to severe pain is high among patients undergoing spinal surgery. Nefopam can be used as an adjuvant analgesic postoperatively after spine surgery. The study aimed to assess the analgesic efficacy and side effects of nefopam on 24-hour postoperative morphine consumption after spine surgery. Methods: The study is a randomized, double-blinded, placebo-controlled trial. A total of 96 patients were randomized into 4 treatment groups, 24 each. In group 1, patients received normal saline before surgical incision and before the end of surgery. In group 2, patients received 30 mg nefopam before surgical incision and normal saline before the end of surgery. In group 3, patients received normal saline before surgical incision and 30 mg of nefopam before the end of surgery. In group 4, patients received 30 mg of nefopam in both timings. Patient-controlled analgesia morphine was used for the postoperative period. Outcomes were to determine 24-hour morphine consumption and incidence of side effects.  Results: Of 96 patients enrolled, 21 in placebo-placebo, 22 in nefopam-placebo, 22 in placebo-nefopam and 21 in nefopam-nefopam groups completed the study.  Analysis of the Kruskal-Wallis test on the intention-to-treat basis shows no significant difference in 24-hour postoperative morphine consumption between four groups, which were 18 [IQR 13.5-29], 20 [IQR 11-28.3], 17 [IQR 11.5-28.5], 13 [IQR 8.5-18.5] mg., respectively (p = 0.223). Incidence of side effects, including tachycardia, sedation, sweating and nausea/ vomiting, did not differ. Conclusions: Adding perioperative nefopam to opioid analgesic does not improve analgesic efficacy in patients who underwent spine surgery. Registration: Thai Clinical Trials Registry ID TCTR20171115001; registered on 15 November 2017.

Analgesic efficacy of intravenous nefopam after spine surgery: a randomized, double-blind, placebo-controlled trial

Background: The incidence of moderate to severe pain is high among patients undergoing spinal surgery. Nefopam can be used as an adjuvant analgesic postoperatively after spine surgery. The study aimed to assess the analgesic efficacy and side effects of nefopam on 24-hour postoperative morphine consumption after spine surgery. Methods: The study is a randomized, double-blinded, placebo-controlled trial. A total of 96 patients were randomized into 4 treatment groups, 24 each. In group 1, patients received normal saline before surgical incision and before the end of surgery. In group 2, patients received 30 mg nefopam before surgical incision and normal saline before the end of surgery. In group 3, patients received normal saline before surgical incision and 30 mg of nefopam before the end of surgery. In group 4, patients received 30 mg of nefopam in both timings. Patient-controlled analgesia morphine was used for the postoperative period. Outcomes were to determine 24-hour morphine consumption and incidence of side effects.  Results: Of 96 patients enrolled, 21 in placebo-placebo, 22 in nefopam-placebo, 22 in placebo-nefopam and 21 in nefopam-nefopam groups completed the study. Analysis of the Kruskal-Wallis test shows no significant difference in 24-hour postoperative morphine consumption between four groups, which were 18 [IQR 13.5-29], 20 [IQR 11-28.3], 17 [IQR 11.5-28.5], 13 [IQR 8.5-18.5] mg., respectively (p = 0.223).  Incidence of side effects, including tachycardia, sedation, sweating and nausea/ vomiting, did not differ. Conclusions: Adding perioperative nefopam to opioid analgesic does not improve analgesic efficacy in patients who underwent spine surgery. Registration: Thai Clinical Trials Registry ID TCTR20171115001; registered on 15 November 2017.

Why mu-opioid agonists have less analgesic efficacy in neuropathic pain?

Injury to peripheral nerves often leads to abnormal pain states (hyperalgesia, allodynia and spontaneous pain), which can remain long after the injury heals. Although opioid agonists remain the gold standard for the treatment of moderate to severe pain, they show reduced efficacy against neuropathic pain. In addition to analgesia, opioid use is also associated with hyperalgesia and analgesia tolerance, whose underlying mechanisms share some commonalities with nerve injury-induced hypersensitivity. Here, we reviewed up-to-day research exploring the contribution of mu-opioid receptor (MOR) on the pathophysiology of neuropathic pain and on analgesic opioid actions under these conditions. We focused on the specific contributions of MOR populations at peripheral, spinal and supraspinal level. Moreover, evidences of neuroplastic changes that may underlie the low efficacy of MOR agonists under neuropathic pain conditions are reviewed and discussed. Sensitization processes leading to pain hypersensitivity, molecular changes in signalling pathways triggered by MOR and glial activation are some of these mechanisms elicited by both nerve injury and opioid exposure. Nerve injury-induced pain hypersensitivity might be masking the initial analgesic effects of opioid agonists, and alternatively, sustained opioid treatment to individuals already suffering from neuropathic pain could aggravate their pathophysiological state. Finally, some combined therapies that can increase opioid analgesic effectiveness in neuropathic pain treatment are highlighted. SIGNIFICANCE: This review provides evidence of the low benefit of opioid monotherapy in neuropathic pain and analyses the reasons of this reduced effectiveness. Opioid agonists along with drugs targeted to block the sensitization processes induced by MOR stimulation might result in a better management of neuropathic pain.

Effects of nefopam on catheter-related bladder discomfort in patients undergoing ureteroscopic litholapaxy

BACKGROUND

Patients who undergo urinary catheterization may experience postoperative catheter-related bladder discomfort (CRBD). Previous studies have indicated that drugs with antimuscarinic effects could reduce the incidence and severity of CRBD. Accordingly, this study was carried out to investigate whether nefopam, a centrally acting analgesic with concomitant antimuscarinic effect, reduces the incidence and severity of CRBD.

METHODS

Sixty patients with American Society of Anesthesiologists physical status I and II and aged 18-70 years who were scheduled to undergo elective ureteroscopic litholapaxy participated in this double-blinded study. Patients were divided into control and nefopam groups, comprising 30 patients each. In the nefopam group, 40 mg nefopam in 100 ml of 0.9% saline was administered intravenously. In the control group, only 100 ml of 0.9% saline was administered. All patients had a urethral catheter and ureter stent inserted during surgery. The incidence and severity of CRBD, numerical rating scale (NRS) score of postoperative pain, rescue pethidine dose, and side effects were recorded in the post-anesthesia care unit after surgery.

RESULTS

The incidence (P = 0.020) and severity (P < 0.001) of CRBD were significantly different between the control group and the nefopam group. The NRS score of postoperative pain (P = 0.006) and rescue dose of pethidine (P < 0.001) were significantly higher in the control group than in the nefopam group.

CONCLUSIONS

Intravenous administration of nefopam in patients scheduled to undergo ureteroscopic litholapaxy reduced the incidence and severity of CRBD, NRS score of postoperative pain and analgesic requirements.

The efficacy and safety of nefopam for pain relief during laparoscopic cholecystectomy: A meta-analysis

BACKGROUND

Pain control after laparoscopic cholecystectomy (LC) has become an important topic. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the efficacy and safety of nefopam for pain management after LC.

METHODS

PubMed, Medline, Embase, ScienceDirect, and the Cochrane Library were searched up to November 2017 for comparative articles involving nefopam and placebo for reducing postoperative pain after LC. Primary outcomes were postoperative pain scores and opioid consumption. Secondary outcomes were length of hospital stay, opioid-related adverse effects, and postoperative complications. We assessed statistical heterogeneity for each RCT by using a standard Chi test and the I statistic. The meta-analysis was undertaken using Stata 12.0.

RESULTS

A total of 215 patients were analyzed across 4 RCTs. We found that there were significant differences between nefopam and placebo groups regarding the postoperative pain scores and opioid requirements at 6, 12, and 24 hours. Moreover, there was a decreased risk of opioid-related adverse effects in the nefopam groups. No significant differences were identified in terms of the incidence of postoperative complications.

CONCLUSION

Intravenous nefopam infusion resulted in significant reduction in postoperative pain scores and opioid requirements while decreasing opioid-related adverse effects. Additionally, no increased risk of venous thromboembolism was found. The current evidence suggests that more RCTs will be needed in further investigations.

Effect of intravenous ketamine for postoperative analgesia in patients undergoing laparoscopic cholecystectomy: A meta-analysis

BACKGROUND

We conducted a meta-analysis to assess the efficacy and safety of ketamine for reducing pain and narcotic use for patients undergoing laparoscopic cholecystectomy (LC).

METHODS

PubMed, Embase, Web of science, Medline, and Cochrane library databases were systematically searched. Randomized controlled trials (RCTs) were regarded as eligible in our study. After testing the heterogeneity across RCTs, data were aggregated for fixed/random effect model according to the I statistic. The meta-analysis was conducted using Stata 11.0 software.

RESULTS

Five studies were included, with a total sample size of 212 patients. Current meta-analysis revealed that there were significant differences regarding postoperative pain score at 12 hours [standard mean difference (SMD) = -0.322, 95% confidence interval (95% CI): -0.594 to -0.050, P = .020], 24 hours (SMD = -0.332, 95% CI: -0.605 to -0.059, P = .017), and 48 hours (SMD = -0.340, 95% CI: -0.612 to -0.068, P = .014). Ketamine intervention was found to significantly decrease narcotic use at 12 hours (SMD = -0.296, 95% CI: -0.567 to -0.025, P = .033), 24 hours (SMD = -0.310, 95% CI: -0.581 to -0.039, P = .025), and 48 hours (SMD = -0.338, 95% CI: -0.609 to -0.066, P = .015).

CONCLUSION

Ketamine appeared to significantly reduce postoperative pain and narcotic use following LC. On the basis of the current evidence available, higher quality RCTs are still required for further research.

Efficiency and safety of ketamine for pain relief after laparoscopic cholecystectomy: A meta-analysis from randomized controlled trials

OBJECTIVE

This meta-analysis aims to evaluate the effectiveness of intravenous infusion of ketamine for pain control after laparoscopic cholecystectomy (LC).

METHODS

A systematic search was performed in PubMed (1966-2017.08), Medline (1966-2017.08), Embase (1980-2017.08), ScienceDirect (1985-2017.08) and the Cochrane Library. Only randomized controlled trials (RCTs) were included. Meta-analysis was performed using Stata 11.0 software.

RESULTS

A total of six RCTs were retrieved involving 294 patients. The present meta-analysis showed that there were significant differences between groups in terms of visual analogue scale scores at 12 h (WMD = -0.478, 95% CI: -0.934 to -0.021, P = 0.040), 24 h (WMD = -0.550, 95% CI: -1.099 to -0.002, P = 0.049), and 48 h (WMD = -0.350, 95% CI: -0.678 to -0.021, P = 0.037) after LC. Significant differences were found regarding opioid consumption at 12 h (WMD = -2.820, 95% CI: -5.170 to -0.470, P = 0.019), 24 h (WMD = -3.816, 95% CI: -7.155 to -0.478, P = 0.025), and 48 h (WMD = -2.210, 95% CI: -4.046 to -0.375, P = 0.018) after LC.

CONCLUSION

Intravenous ketamine infusion significantly reduced postoperative pain scores and opioid consumption after LC. In addition, there were fewer adverse effects in the ketamine groups. Higher quality RCTs are still required for further research.

Statistical data presentation

Data are usually collected in a raw format and thus the inherent information is difficult to understand. Therefore, raw data need to be summarized, processed, and analyzed. However, no matter how well manipulated, the information derived from the raw data should be presented in an effective format, otherwise, it would be a great loss for both authors and readers. In this article, the techniques of data and information presentation in textual, tabular, and graphical forms are introduced. Text is the principal method for explaining findings, outlining trends, and providing contextual information. A table is best suited for representing individual information and represents both quantitative and qualitative information. A graph is a very effective visual tool as it displays data at a glance, facilitates comparison, and can reveal trends and relationships within the data such as changes over time, frequency distribution, and correlation or relative share of a whole. Text, tables, and graphs for data and information presentation are very powerful communication tools. They can make an article easy to understand, attract and sustain the interest of readers, and efficiently present large amounts of complex information. Moreover, as journal editors and reviewers glance at these presentations before reading the whole article, their importance cannot be ignored.

The Effect of Nefopam Infusion during Laparascopic Cholecystectomy on Postoperative Pain

Background: While recovery from remifentanil is fast due to its rapid metabolism, it can induce hyperalgesia by activation of N-methyl-D-aspartic acid (NMDA) receptors. Therefore, administration of NMDA receptor antagonists such as ketamine is effective in relieving hyperalgesia caused by remifentanil. A previous study showed that nefopam administration before anesthesia combined with low-dose remifentanil reduced pain and analgesic consumption during the immediate postoperative period. We hypothesized that intraoperative infusion of nefopam during laparoscopic cholecystectomy would be as effective as ketamine in controlling pain during the acute postoperative period after sevoflurane and remifentanil based anesthesia. Methods: Sixty patients scheduled to undergo laparoscopic cholecystectomy were randomly divided into three groups. General anesthesia was maintained with sevoflurane and effect-site target concentration of remifentanil (4 ng/ml) in all patients. An intravenous bolus of nefopam (0.3 mg/kg) was given, followed by continuous infusion (65 µg/kg/h) in Group N (n=20). An intravenous bolus of ketamine (0.3 mg/kg) was administered, followed by continuous infusion (180 µg/kg/h) in Group K (n=20), and Group C received a bolus and subsequent infusion of normal saline equal to the infusion received by Group K (n=20). We compared postoperative Visual Analogue Scale (VAS) scores and analgesic requirements over the first 8 postoperative hours between groups. Results: The pain scores (VAS) and fentanyl requirements for 1 h after surgery were significantly lower in the nefopam and ketamine groups compared with the control group (p<0.05). There were no differences between the nefopam and ketamine groups. The three groups showed no differences in VAS scores and number of analgesic injections from 1 to 8 h after surgery. Conclusion: Intraoperative nefopam infusion during laparoscopic cholecystectomy reduced opioid requirements and pain scores (VAS) during the early postoperative period after remifentanil-based anesthesia.