Intrathecal meperidine for elective caesarean section: a comparison with lidocaine

The Effectiveness of Caudal Block with Low Doses of Dexmedetomidine and Pethidine in Transrectal Prostate Biopsy: Preliminary Results

PURPOSE

To evaluate the effectiveness of caudal block (CB) using dexmedetomidine and pethidine instead of local anesthesia (LA) for prostate needle biopsy and the effect of CB on urinary retention.

MATERIAL AND METHODS

A transrectal ultrasound-guided prostate needle biopsy (TRUS-Bx) was performed on 68 patients with a mean age of 65 ± 2.18 years. CB with a combination of dexmedetomidine and pethidine without LA was administered to the patients. The pain levels of the patients were determined using numeric rating scale (NRS) scores to evaluate the effectiveness of CB. Preoperative and postoperative postvoid residual urine volumes (PRUV) were also calculated.

RESULTS

The CB success rate was 93.15%. The NRS scores were 0.79 ± 0.19 and 0.89 ± 0.22 during probe entry and manipulation and biopsy, respectively, without any significant differences between them (p = 0.382). The mean PRUVs before and after biopsy did not differ significantly (41 ± 15.6 vs. 71.93 ± 22.3, p = 0.379). The degree of sedation, as assessed using the Ramsay scale, was 2 or 3 in all patients.

CONCLUSION

The combination of dexmedetomidine and pethidine for CB in TRUS-Bx provided quality analgesia for the patient and prevented the development of postoperative urinary retention.

Effect of intrathecal lipophilic opioids on the incidence of shivering in women undergoing cesarean delivery after spinal anesthesia: a systematic review and bayesian network meta- analysis of randomized controlled trials

Background

Shivering is a common side effect in women having cesarean delivery (CD) under spinal anesthesia, which can be bothersome to the patient, and it can also interfere with perioperative monitoring. In several studies, the intrathecal (IT) addition of a lipophilic opioid to local anesthetics has been shown to decrease the incidence of shivering.

Objective

We performed this network meta-analysis to evaluate the effects of intrathecal lipophilic opioids in preventing the incidence of shivering in patients undergoing CD.

Methods

This review was planned according to the PRISMA for Network Meta-Analysis (PRISMA-NMA) guidelines. An English literature search of multiple electronic databases was conducted. We included randomized controlled trials (RCTs) that reported on the incidence of shivering, with study groups receiving either IT fentanyl, sufentanil, or meperidine in women undergoing CD under spinal anesthesia. Quality of the studies was assessed using the modified Oxford scoring system. Using random-effects modeling, dichotomous data were extracted and summarized using odds ratio (OR) with a 95% credible interval (CrI). Statistical analysis was conducted using R studio version 1.0.153 - Inc.

Results

Twenty-one studies consisting of 1433 patients (Control group: 590 patients in twenty-one studies; Fentanyl group:199 patients in seven studies; Sufentanil group: 156 patients in five studies; Meperidine group: 488 patients in ten studies) met the inclusion criteria for this systematic review investigating the effect of intrathecal lipophilic opioids in preventing the incidence of shivering in women undergoing cesarean delivery under spinal anesthesia. Methodological validity scores ranged from 3 to 7. The Bayesian mixed network estimate showed the incidence of shivering was significantly lower with IT fentanyl (pooled odds ratio (OR): 0.13; 95% credible interval (CrI): 0.04 to 0.35; P = 0.0004) and IT meperidine (OR: 0.12; 95% CrI: 0.05 to 0.29; P < 0.00001), but not with IT sufentanil (OR: 0.37; 95% CrI: 0.11 to 1.22; P = 0.23). The IT fentanyl group had a significantly lower incidence of intraoperative discomfort [Risk Ratio (RR): 0.19; 95% CI: 0.10–0.35; P < 0.00001], the IT sufentanil group had a significantly higher incidence of pruritus (RR: 6.18; 95% CI: 1.18–32.46; P = 0.03) The IT meperidine group had a significantly lower incidence of intraoperative discomfort (2.7% vs. 13.6%; RR: 0.22; 95% CI: 0.09–0.55; P = 0.001), but there was a significant increase in nausea and vomiting (IT meperidine group vs. Control group: 42.7% vs. 19.4%; RR: 2.56; 95% CI: 1.14–5.75; P = 0.02). Meta-regression analysis based on the opioid dose and quality of the study did not impact the final inference of our result.

Conclusion

IT fentanyl significantly decreased the incidence of shivering in women undergoing CD under spinal anesthesia without increasing maternal adverse events, confirming that routine use in this patient population is a good choice. IT sufentanil did not decrease the incidence of shivering. IT meperidine decreased the incidence and severity of shivering, but its use was also associated with significant nausea and vomiting.

The Effect of Intrathecal Meperidine on Maternal and Newborn Outcomes After Cesarean Section: A Systematic Review and Meta-Analysis Study

Context

Spinal anesthesia is the most preferred method for cesarean section. This meta-analysis was performed to determine the effect of minimum and maximum intrathecal doses of meperidine (pethidine) [5 to 40 mg] on the maternal and newborn outcomes after cesarean section.

Evidence Acquisition

The data were collected through the systematic search in the ISI, PubMed, Scopus, Google Scholar, Barakat, MagIran, SID, Irandoc, and EMBASE medical databases. Eighteen clinical trial studies with 1,494 patients were included.

Results

Patients who had received intrathecal meperidine had experienced lower shivering, relative risk [RR] = 0.34 (95% CI = 0.23, 0.48) and longer analgesia, [standard mean difference (SMD)] = 7.67 (95% CI = 1.85, 13.49) after the surgery. Moreover, RR of nausea = 1.37 (95% CI = 1.13, 1.66), vomiting RR = 2.02 (95% CI = 1.28, 3.20), and pruritus RR = 9.26 (95% CI = 4.17, 20.58) was higher in the pethidine group than in the control group. There was no statistically significant difference in the Apgar score at one-minute RR = 0.99 (95% CI = 0.9, 1.09), at five-minute RR = 0.93 (95% CI = 0.87, 1.08), maternal hypotension RR = 1.00 (95% CI = 0.87, 1.15), and maternal sensory and motor blockade durations, SMD = -1.72 (95% CI = -3.78.0.34) and SMD = -4.38 (95% CI = -9.19, 0.44), respectively in the two pethidine and control groups.

Conclusions

Intrathecal meperidine can reduce shivering and increase the duration of postoperative analgesia, though it increases the relative risk of nausea, vomiting, and pruritus. No significant difference was found both in the Apgar score, maternal hypotension, and duration of the motor and sensory block.

A Comparison of Continuous Thoracic Epidural Analgesia with Bupivacaine Versus Bupivacaine and Dexmedetomidine for Pain Control in Patients with Multiple Rib Fractures

Background

The control of pain in traumatic patients with chest injury leading to rib fracture is one of the primary goals in traumatic patients. The efficacy of the thoracic epidural approach in comparison with other approaches for relieving post-thoracotomy pain is unknown. The goal of the present study was to compare thoracic epidural analgesia with bupivacaine alone and in combination with dexmedetomidine in patients with multiple rib fractures.

Methods

64 traumatic patients with multiple rib fractures were selected and randomly assigned to two similar groups. For pain relief, a thoracic epidural catheter was inserted to infuse bupivacaine alone or the combination of bupivacaine and dexmedetomidine. Then, we recorded and analyzed pain scores and ABG changes.

Results

Based on the results, the two approaches could result in proper analgesia, but analgesia with the combination of bupivacaine and dexmedetomidine was significantly improved compared to bupivacaine alone (P < 0.05). In addition, ABG of patients significantly changed when the combination of bupivacaine and dexmedetomidine was used within 2 to 4 days (P < 0.05).

Conclusions

The results of the present study showed that epidural infusion of a combination of bupivacaine and dexmedetomidine could provide better control of rib fracture pain in traumatic patients, and is a proper alternative for bupivacaine alone.

Preventing shivering with adjuvant low dose intrathecal meperidine: A meta-analysis of randomized controlled trials with trial sequential analysis

The aim of this systematic review and meta-analysis is to evaluate the pros and cons of adjuvant low dose intrathecal meperidine for spinal anaesthesia. We searched electronic databases for randomized controlled trials using trial sequential analysis (TSA) to evaluate the incidence of reduced rescue analgesics, shivering, pruritus, nausea and vomiting when applying adjuvant intrathecal meperidine. Twenty-eight trials with 2216 patients were included. Adjuvant intrathecal meperidine, 0.05-0.5 mg kg-1, significantly reduced incidence of shivering (relative risk, RR, 0.31, 95% confidence interval, CI, 0.24 to 0.40; TSA-adjusted RR, 0.32, 95% CI, 0.25 to 0.41). Intrathecal meperidine also effectively reduced need for intraoperative rescue analgesics (RR, 0.27, 95% CI, 0.12 to 0.64; TSA-adjusted RR, 0.27, 95% CI, 0.08 to 0.91) and the incidence of pruritus was unaffected (RR, 2.31, 95% CI, 0.94 to 5.70; TSA-adjusted RR, 1.42, 95% CI, 0.87 to 2.34). However, nausea and vomiting increased (RR, 1.84, 95% CI, 1.29 to 2.64; TSA-adjusted RR, 1.72, 95% CI, 1.33 to 2.23; RR, 2.23, 95% CI, 1.23 to 4.02; TSA-adjusted RR,1.96, 95% CI, 1.20 to 3.21). Under TSA, these results provided a sufficient level of evidence. In conclusion, adjuvant low dose intrathecal meperidine effectively attenuates spinal anaesthesia-associated shivering and reduces rescue analgesics with residual concerns for the nausea and vomiting.

Spinal pethidine for elective caesarean section

Pethidine (meperidine) is a unique member of the opioid family. In addition to its analgesic activity, it also has significant local anaesthetic activity. This property enables it to be used as the sole agent for spinal anaesthesia. We describe the successful use of intrathecal pethidine 1 mg/kg for an elective lower segment caesarean section in a patient presumed to be allergic to amide local anaesthetics. There were no significant adverse effects in either the mother or the newborn.

Combination of low-dose bupivacaine and opioids provides satisfactory analgesia with less intraoperative hypotension for spinal anesthesia in cesarean section

AIMS

This meta-analysis was undertaken to compare the three most common drug regimens of bupivacaine in spinal anesthesia for cesarean section: high-dose bupivacaine (≥10 mg, HB), low-dose bupivacaine (<10 mg, LB) and combination of low-dose bupivacaine and opioids (LBO).

METHODS

Databases of MEDLINE, EMBASE, and Cochrane Library were searched (updated on October 30, 2011). Primary endpoints were the incidence of intraoperative hypotension and analgesia efficacy. Pooled risk ratio (RR) or standard mean difference and their 95% confidence intervals (95% CI) were calculated. A RR <1 indicates that LB or LBO regimen is associated with less intraoperative complications and better anesthesia or analgesia efficacy.

RESULTS

A total of 11 randomized controlled trials including 605 parturients were analyzed. Results of this meta-analysis showed that compared with HB regimen, LB regimen decreased the incidence of intraoperative hypotension (RR = 0.64, 95% CI: 0.42-0.96) with less satisfactory analgesia (fixed model, RR = 1.50, 95% CI: 1.14-1.98). LBO regimen significantly reduced the incidence of intraoperative hypotension (RR = 0.52, 95% CI: 0.33-0.82) with reliable analgesia efficacy (RR = 2.56, 95% CI: 0.77-8.48).

CONCLUSION

Compared with conventional HB regimen and LB regimen, LBO regimen not only reduced intraoperative hypotension but also provided reliable analgesia. Therefore, LBO regimen should be considered as the preferred drug combination for spinal anesthesia in cesarean section.

Improvement of quality of reporting in randomised controlled trials to prevent hypotension after spinal anaesthesia for caesarean section

Hypotension is a frequent complication of spinal anaesthesia for caesarean section and can threaten the well-being of the unborn child. Numerous randomised controlled trials (RCTs) dealt with measures to prevent hypotension. The aim of this study was to determine the reporting quality of RCTs using the Consolidated Standards of Reporting Trials (CONSORT) statement since low quality can lend false credibility to a study and overestimate the effect of an intervention. We performed a systematic literature search in PubMed to identify relevant RCTs in a pre-CONSORT period (1990-1994) and a post-CONSORT period (2004-2008). A comparative evaluation was done between the two periods, and the trials were assessed for compliance with each of the 22 CONSORT items. A total of 37 RCTs was identified. The CONSORT score increased significantly (p < 0.05) from 66.7% (±12.5%) in the pre-CONSORT period to 87.4% (±6.9%) in the post-CONSORT period. A statistically significant improvement was found for eight items, including randomization, blinding and intention-to-treat analysis. The CONSORT score in the post-CONSORT era was fairly good, also in comparison to other medical fields. In the post-CONSORT era, reporting of important items improved, in particular in the domains that are crucial to avoid bias and to improve internal validity. Use of CONSORT should be encouraged in order to keep or even improve the reporting quality.

Combining Intrathecal Bupivacaine and Meperidine during Caesarean Section to Prevent Spinal Anaesthesia-Induced Hypotension and other Side-Effects

This study compared intrathecal hyperbaric bupivacaine with low-dose intrathecal plain bupivacaine plus different doses of meperidine (pethidine), administered sequentially, with regard to blood pressure stability, post-operative analgesia and incidence of side-effects in 80 parturients undergoing caesarean section. Patients were randomly assigned to one of four groups ( n = 20 each group): the HB group received 10 mg hyperbaric bupivacaine intrathecally; the BM35, BM30 and BM25 groups received 5 mg plain bupivacaine plus 35, 30 or 25 mg of meperidine intrathecally, respectively. The incidence of hypotension in the BM25 group was significantly lower than in the HB group. Nausea and vomiting were less prevalent in the BM25 group than in the HB and BM35 groups. In conclusion, sequential administration of 5 mg plain bupivacaine and 25 mg meperidine intrathecally provided better blood pressure stability and a lower incidence of side-effects than bupivacaine alone, without affecting quality of anaesthesia or surgical and patient satisfaction.

Low-dose spinal anaesthesia for caesarean section

PURPOSE OF REVIEW

The literature on the appropriate dose of local anaesthetic and combinations with opioids for spinal anaesthesia for caesarean section in patients without comorbid conditions is reviewed. The controversial issue of spinal anaesthesia in severe preeclampsia is also addressed.

RECENT FINDINGS

Recent comparisons with ropivacaine and levobupivacaine suggest that bupivacaine remains the best agent for spinal anaesthesia for caesarean section. The addition of various combinations of opioids has allowed a reduction in the dose of bupivacaine. Intrathecal diamorphine has been extensively investigated and appears to have a favourable pharmacokinetic and pharmacodynamic profile. In severe preeclampsia, spinal anaesthesia may be associated with less hypotension than in healthy parturients, where similar doses of local anaesthetic are used.

SUMMARY

Low-dose spinal anaesthesia has been advocated in the interests of improving cardiovascular stability. However, current sophistication of knowledge concerning spinal anaesthetic technique makes cardiovascular instability easy to prevent. Therefore this review emphasizes the importance of adequate surgical anaesthesia during caesarean section, and makes suggestions as to the optimal pharmacological agents for intraoperative anaesthesia and postoperative analgesia. Spinal anaesthesia is safe in severe preeclampsia, provided there are no contraindications to regional anaesthesia.

Anesthetic efficacy of lidocaine/meperidine for inferior alveolar nerve blocks

The authors, using a crossover design, randomly administered, in a single-blind manner, inferior alveolar nerve blocks using 36 mg of lidocaine with 18 microg of epinephrine or a combination of 36 mg of lidocaine with 18 microg epinephrine plus 36 mg meperidine with 18 microg of epinephrine, at 2 separate appointments, to 52 subjects. An electric pulp tester was used to test for anesthesia, in 4-minute cycles for 60 minutes, of the molars, premolars, and central and lateral incisors. Anesthesia was considered successful when 2 consecutive 80 readings were obtained within 15 minutes and the 80 reading was continuously sustained for 60 minutes. Using the lidocaine solution, successful pulpal anesthesia ranged from 8 to 58% from the central incisor to the second molar. Using the lidocaine/meperidine solution, successful pulpal anesthesia ranged from 0 to 17%. There was a significant difference (P < .05) between the lidocaine and lidocaine/meperidine solutions for the lateral incisors through the second molars. We conclude that the addition of meperidine to a standard lidocaine solution does not increase the success of the inferior alveolar nerve block.

Anesthetic Efficacy of Lidocaine/Meperidine for Inferior Alveolar Nerve Blocks in Patients with Irreversible Pulpitis

The purpose of this prospective, randomized, single-blind study was to compare the anesthetic efficacy of lidocaine with epinephrine to lidocaine plus meperidine with epinephrine for inferior alveolar nerve blocks (IAN) in patients with mandibular posterior teeth experiencing irreversible pulpitis. Forty-eight emergency patients diagnosed with irreversible pulpitis of a mandibular posterior tooth randomly received, in a single-blind manner, 36 mg of lidocaine with 18 mug epinephrine or 36 mg of lidocaine with 18 mug of epinephrine plus 36 mg meperidine with 18 mug epinephrine, using a conventional inferior alveolar nerve block. Endodontic access was begun 15 minutes after solution deposition, and all patients were required to have profound lip numbness. Success was defined as no or mild pain (visual analog scale recordings) upon endodontic access or initial instrumentation. The success rate for the inferior alveolar nerve block using the lidocaine solution was 26%, and for the lidocaine/meperidine solution, the success rate was 12%. There was no significant difference (p = 0.28) between the two solutions. In conclusion, for mandibular posterior teeth with irreversible pulpitis, the addition of 36 mg of meperidine to a lidocaine solution administered in a conventional IAN block did not improve the success rate over a standard lidocaine solution.

Post-Cesarean Delivery Analgesia

Post-cesarean delivery pain relief is important. Good pain relief will improve mobility and can reduce the risk of thromboembolic disease, which is increased during pregnancy. Pain may also impair the mother's ability to optimally care for her infant in the immediate postpartum period and may adversely affect early interactions between mother and infant. Pain and anxiety may also reduce the ability of a mother to breast-feed effectively. It is necessary that pain relief be safe and effective, that it not interfere with the mother's ability to move around and care for her infant, and that it result in no adverse neonatal effects in breast-feeding women. The most commonly used modalities are systemic administration of opioids, either by intramuscular injection or i.v. by patient-controlled analgesia, and neuraxial injection of opioid as part of a regional anesthetic for cesarean delivery. These techniques have specific advantages and disadvantages which will be discussed in this review. In addition, there are new drug applications of potential benefit for the treatment of post-cesarean delivery pain.

Continuous Intrathecal Meperidine for Severe Refractory Cancer Pain

The control of severe cancer pain may be problematic despite advances in pain management. Patients with severe intractable pain and/or intractable side effects may require aggressive interventional pain management strategies including the administration of medications by the continuous intrathecal route and/or neurosurgical procedures. Various medications, including opioids, local anesthetics, and alpha-2 agonists may be used intrathecally for the control of cancer pain. Failure of the intrathecal route may require the additional use of neurosurgical procedures such as cordotomy for pain control. We describe a case of severe cancer pain refractory to conventional intrathecal medications and cordotomy that was successfully managed by the addition of meperidine to the intrathecal regimen.

Intrathecal fentanyl/meperidine combined with low-dose epidural bupivacaine for Cesarean section in a patient with advanced Krukenberg tumors

This case report demonstrates the anesthetic management of a 41-year-old primiparous parturient with massive ascites due to advanced Krukenberg tumors, undergoing Cesarean section. We chose a combined intrathecal-epidural technique, using intrathecal hypobaric fentanyl and hyperbaric meperidine, and a low dose of epidural bupivacaine in order to avoid hemodynamic instability in this critically ill patient. Surgery was carried out without difficulty under adequate regional anesthesia. The blood pressure was maintained with low doses of phenylephrine and dopamine. Opioid-related complications such as nausea-vomiting, pruritus, drowsiness, and respiratory depression were not observed in this patient. Therefore, intrathecal opioids combined with a low dose of epidural local anesthetics for Cesarean section is suitable for critically ill patients with malignant abdominal tumors, such as a Krukenberg tumor, complicated by massive ascites.

Continuous spinal analgesia for labor and delivery in a parturient with hypertrophic obstructive cardiomyopathy

Induction of labor under analgesia was planned for a 30-year-old-primiparous patient with hypertrophic obstructive cardiomyopathy (HOCM), as her fetal evaluation revealed intrauterine growth restriction at 38 weeks' gestation. However, regional analgesia during labor may present a potential risk for hemodynamic instability in patients with HOCM due to the possibility of a sympathetic block, as a result of vasodilation associated with the administration of local anesthesia. This case report demonstrates the successful management of the patient with analgesia provided by a continuous spinal catheter dosed with a continuous infusion of fentanyl and supplemental meperidine. Fetal surveillance monitoring included fetal pulse oximetry in addition to conventional cardiotocography, on the basis of which cesarean section was avoided.

Addition of meperidine to bupivacaine for spinal anaesthesia for Caesarean section

BACKGROUND

In a prospective, randomized, double-blind, placebo-controlled trial, we investigated the effect of adding meperidine 10 mg to intrathecal bupivacaine on the duration of early postoperative analgesia in 40 patients having elective Caesarean section under spinal anaesthesia.

METHODS

Patients received intrathecal injection of 0.5% hyperbaric bupivacaine 2.0 ml plus either normal saline 0.2 ml (saline group) or 5% meperidine 0.2 ml (meperidine group). After operation, all patients were given i.v. patient-controlled analgesia using morphine.

RESULTS

The duration of effective analgesia, defined as the time from intrathecal injection to first patient-controlled analgesia demand, was greater in the meperidine group (mean 234 min, 95% confidence interval 200-269 min) compared with the saline group (mean 125 min, 95% confidence interval 111-138 min; P<0.001). The 24 h morphine requirement was similar in the two groups. The meperidine group had a greater incidence of intraoperative nausea or vomiting compared with the saline group (11 vs 3; P=0.02).

CONCLUSION

Addition of meperidine 10 mg to intrathecal bupivacaine for Caesarean section is associated with prolonged postoperative analgesia but with greater intraoperative nausea and vomiting.

The effects of three graded doses of meperidine for spinal anesthesia in African men

The intrathecal injection of 0.7-1 mg/kg meperidine provides spinal anesthesia of only short duration. In this study, we investigated the effects of three different doses of meperidine for spinal anesthesia on the duration and level of sensory block and the incidence of side effects. Forty-five African men were randomly allocated to receive one of three doses of intrathecal meperidine: Group A = 1.2 mg/kg, Group B = 1.5 mg/kg, and Group C = 1.8 mg/kg. The duration of sensory block was significantly longer after 1.5 mg/kg compared with 1.2 mg/kg meperidine (112 +/- 19 vs 79 +/- 27 min; P = 0.001). Increasing the dose to 1.8 mg/kg did not further increase the duration of block. The level and the onset of the block were not affected by the dose. Common side effects were fatigue (27%), pruritus (20%), and nausea (7%). Seven patients had respiratory depression and seven had a decrease of systolic arterial blood pressure (SAP) >30% from baseline. There was no difference in the incidence of any side effect among groups. Respiratory depression and decreases in SAP were observed 5-50 min after meperidine injection. Twenty-two patients had no pain after the sensory block had terminated. We conclude that increasing the dose of meperidine from 1.2 to 1.5 mg/kg increased the duration, but not the level, of sensory block without an increase in side effects.

IMPLICATIONS

Intrathecal meperidine 1 mg/kg provides surgical anesthesia for only 40-90 min. We investigated the effects of three larger doses of meperidine in 45 African men. The 1.5 and 1.8 mg/kg doses provide a longer duration of anesthesia compared with 1.2 mg/kg. Nausea, pruritus, and respiratory depression were common in all dose groups. We conclude that increasing the dose of meperidine from 1.2 to 1.5 mg/kg increased the duration, but not the level, of sensory block without an increase in side effects.

Intrathecal pethidine: pharmacology and clinical applications

Pethidine is the only member of the opioid family that has clinically important local anaesthetic activity in the dose range normally used for analgesia. Pethidine is unique as the only opioid in current use that is effective as the sole agent for spinal anaesthesia. In lower doses, intrathecal pethidine is also an effective analgesic for treating pain in labour. This paper reviews the pharmacology of intrathecal pethidine and clinical experience reported to date. Articles reviewed include those identified by a Medline search using keywords "intrathecal" or "spinal anaesthesia/ anesthesia" and "pethidine" or "meperidine". Reference lists from identified papers were scrutinized to identify further relevant articles.

Intrathecal pethidine: an alternative anaesthetic for transurethral resection of prostate?

We aimed to determine the usefulness of intrathecal pethidine as the sole anaesthetic for transurethral resection of prostate (TURP) while comparing the incidence of hypotension with intrathecal bupivacaine. A double-binded randomized prospective trial was conducted involving 40 patients for TURP. The patients were divided equally into two groups; group A received 2 ml 0.5% bupivacaine intrathecally and group B received 40 mg pethidine intrathecally. Changes in blood pressure and heart rate were measured over the first 30 minutes. The highest sensory block and the time to reach it were documented. The degree of motor blockade was also recorded. There was no significant difference in the incidence of hypotension. The pethidine group had significantly greater reduction in heart rate, a lower degree of motor block, shorter period before requests for postoperative analgesia but a higher incidence of sedation, nausea and vomiting. Intrathecal pethidine did not offer any advantage over intrathecal bupivacaine for TURP.

Patient-controlled epidural analgesia after caesarean section using meperidine

PURPOSE

To determine the effects of the addition of a background infusion to patient-controlled epidural analgesia (PCEA) using meperidine for analgesia after Caesarean section.

METHODS

In a randomized, double-blind study, we assigned 40 patients having elective Caesarean section to receive postoperative analgesia by patient-controlled epidural analgesia (PCEA) using meperidine 5 mg.ml-1 with (group Pi) or without (group Po) a background infusion of 10 mg.hr-l. The PCEA settings (20 mg bolus, 10 min lockout interval, four-hour maximum dose 150 mg) were otherwise identical. We compared pain at rest, pain on coughing, side effects, number of PCEA demands, drug consumption and patient satisfaction between groups in the first 24 hr after surgery.

RESULTS

Total consumption of meperidine was greater in group Pi (median 390 mg) than in group Po (median 240 mg; P = 0.017) and the number of PCEA demands was greater in group Po (median 12) than in group Pi (median 7.5; P = 0.012). Analgesia, side effects and patient satisfaction was similar between groups.

CONCLUSION

Addition of a background infusion to PCEA using meperidine after Caesarean section has no clinical benefit.

A comparison of the haemodynamic effects of intrathecal meperidine, meperidine-bupivacaine mixture and hyperbaric bupivacaine

PURPOSE

To study the haemodynamic effects of intrathecal meperidine, administered either alone or mixed with bupivacaine.

METHODS

We studied 42 Chinese patients, aged 59-87 yr, scheduled for transurethral bladder or prostate surgery, randomized into three equals groups, that received either meperidine 0.8 mg.kg-1, meperidine 0.4 mg.kg-1 plus 1.5 ml of 0.5% heavy bupivacaine or 3 ml of heavy bupivacaine 0.5%. Non-invasive systolic (SAP) and mean (MAP) arterial pressures, central venous pressure and cardiac index, stroke index and heart rate (HR) measured by the BoMed NCCOM3-R7S bioimpedance device, were recorded over the first 25 min. Systemic vascular resistance index (SVRI) was derived. Onset of sensory and motor block was also measured. Decreases in MAP of 25% were treated with colloid and metaraminol.

RESULTS

The onset of block was slower in the meperidine group (P < 0.05). Decreases in SAP, MAP and SVRI (all; P < 0.001) occurred within five minutes in all three groups. The HR was increased in the bupivacaine group (P = 0.03), but bradycardias treated with atropine occurred in six patients receiving meperidine and four patients receiving the mixture. Six patients receiving meperidine and two patients receiving the mixture required general anaesthesia for inadequate block. The incidence of nausea and vomiting was higher in the patients receiving meperidine (P < 0.05). No other complications were encountered.

CONCLUSIONS

Intrathecal meperidine used alone or mixed with bupivacaine has no intra-operative advantage over heavy bupivacaine 0.5%.

Anaesthesia and adverse effects after intrathecal pethidine hydrochloride for urological surgery

Anaesthesia, postoperative analgesia and the incidence of adverse effects after intrathecal pethidine hydrochloride 0.50 mg.kg-1 and 0.75 mg.kg-1 were assessed and compared with a conventional technique using isobaric bupivacaine 13.75 mg in patients undergoing transurethral resection of the prostate gland. Sensory and motor block were significantly shorter with both pethidine regimens than with bupivacaine (p < 0.001). Although sensory and motor block were shorter after pethidine 0.50 mg.kg-1 than after pethidine 0.75 mg.kg-1 the difference in duration was clinically insignificant. The incidence of incomplete motor block was significantly greater with pethidine 0.50 mg.kg-1 than with bupivacaine 13.75 mg.kg-1 (p < 0.01). Visual analogue pain scores recorded after the operation were low and were similar in the pethidine groups to those obtained with bupivacaine alone. Mean arterial blood pressure was significantly lower in both pethidine groups compared with the bupivacaine group between 30 and 240 min after intrathecal injection (p < 0.001). However, the within-group reductions in blood pressure were within clinically acceptable limits. The incidences of nausea and emesis were low and emesis occurred in patients in the bupivacaine group only (p < 0.03). Pruritus was seen only in patients receiving pethidine. Intra-operative sedation occurred more often in patients receiving both pethidine 0.50 mg.kg-1 and 0.75 mg.kg-1 compared with patients receiving bupivacaine (p < 0.04). Both pethidine regimens provided acceptable anaesthesia and there were no significant differences between the two regimens in quality of intra-operative anaesthesia, incidence of adverse events or postoperative analgesia.