Intrathecal Morphine for Analgesia After Postpartum Bilateral Tubal Ligation

Non-pulmonary complications of intrathecal morphine administration: a systematic review and meta-analysis with meta-regression

BACKGROUND

Intrathecal morphine provides effective analgesia for a range of operations. However, widespread implementation into clinical practice is hampered by concerns for potential side-effects. We undertook a systematic review, meta-analysis, and meta-regression with the primary objective of determining whether a threshold dose for non-pulmonary complications could be defined and whether an association could be established between dose and complication rates when intrathecal morphine is administered for perioperative or obstetric analgesia.

METHODS

We systematically searched the literature for randomised controlled trials comparing intrathecal morphine vs control in patients undergoing any type of surgery under general or spinal anaesthesia, or women in labour. Primary outcomes were rates of postoperative nausea and vomiting, pruritus, and urinary retention within the first 24 postoperative hours, analysed according to doses (1-100 μg; 101-200 μg; 201-500 μg; >500 μg), type of surgery, and anaesthetic strategy. Trials were excluded if doses were not specified.

RESULTS

Our analysis included 168 trials with 9917 patients. The rates of postoperative nausea and vomiting, pruritus, and urinary retention were significantly increased in the intrathecal morphine group, with an odds ratio (95% confidence interval) of 1.52 (1.29-1.79), P<0.0001; 6.11 (5.25-7.10), P<0.0001; and 1.73 (1.17-2.56), P=0.005, respectively. Meta-regression could not establish an association between dose and rates of non-pulmonary complications. There was no subgroup difference according to surgery for any outcome. The quality of evidence was low (Grading of Recommendations Assessment, Development, and Evaluation [GRADE] system).

CONCLUSIONS

Intrathecal morphine significantly increased postoperative nausea and vomiting, pruritus, and urinary retention after surgery or labour in a dose-independent manner.

SYSTEMATIC REVIEW PROTOCOL

PROSPERO (CRD42023387838).

Interventions for intra-operative pain relief during postpartum mini-laparotomy tubal ligation

BACKGROUND

Postpartum mini-laparotomy tubal ligation (PPTL) is a contraceptive method that works by interrupting the patency of the fallopian tubes. Several methods are used for intraoperative pain relief, such as systemic administration of opioids or intraperitoneal instillation of lidocaine.

OBJECTIVES

To evaluate the effectiveness of and adverse effects associated with interventions for pain relief in women undergoing PPTL.

SEARCH METHODS

We searched for eligible studies published on or before 31 July 2017 in the CENTRAL Register of Studies Online, MEDLINE, Embase, PsycINFO, and CINAHL. We examined review articles and searched registers of ongoing clinical trials, citation lists of included studies, key textbooks, grey literature, and previous systematic reviews for potentially relevant studies.

SELECTION CRITERIA

We included randomised controlled trials (RCT) that compared perioperative pain relief measures during PPTL.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the titles, abstracts, and full-text articles of potentially relevant studies for inclusion. We extracted the data from the included studies, assessed risk of bias, and calculated and compared results. Discrepancies were resolved by discussion, or by consulting a third review author. We computed the inverse variance risk ratio (RR) with 95% confidence interval (CI) for binary outcomes, and the mean difference (MD) with 95% CI for continuous variables.

MAIN RESULTS

We found only three RCTs, in which a total of 230 postpartum women participated. Most of our analyses were based on relatively small numbers of patients and studies. Overall, the certainty of evidence regarding the effectiveness of interventions was low, due to risk of bias and imprecision. We found very low-certainty evidence regarding the safety of interventions because of risk of bias and imprecision. Two studies had unclear risk of selection bias. One study had unclear risk of reporting bias and a high risk of other bias associated with the study protocol.Women who received an intraperitoneal instillation of lidocaine experienced lower intensity intraperitoneal pain than those given a placebo (pooled MD -3.34, 95% CI -4.19 to -2.49, three studies, 190 participants, low-certainty evidence), or an intramuscular injection of morphine (MD -4.8, 95% CI -6.43 to -3.17, one study, 40 participants, low-certainty evidence). We found no clear difference in intraperitoneal pain between women who had an intramuscular injection of morphine added to an intraperitoneal instillation of lidocaine and those who had an intraperitoneal instillation of lidocaine alone (MD -0.40, 95% CI -1.52 to 0.72, one study, 40 participants, low-certainty evidence). An intramuscular injection of morphine alone was not effective for intraperitoneal pain relief compared to placebo (MD 0.50, 95% CI -1.33 to 2.33, one study, 40 women, low-certainty evidence). None of the studies reported any serious adverse events but the evidence was very low-certainty. Intraperitoneal instillation of lidocaine may reduce the number of women requiring additional pain control when compared to placebo (RR 0.27, 95% CI 0.17 to 0.44, three studies, 190 women, low-certainty evidence).

AUTHORS' CONCLUSIONS

An intraperitoneal instillation of lidocaine during postpartum mini-laparotomy tubal ligation before fallopian tubes were tied may offer better intraperitoneal pain control, although the evidence regarding adverse effects is uncertain. We found no clear difference in intraperitoneal pain between women who received a combination of an injection of morphine, and intraperitoneal instillation of lidocaine and those who received an intraperitoneal instillation of lidocaine alone. These results must be interpreted with caution, since the evidence overall was low to very low-certainty.

Neuraxial anesthesia for postpartum tubal ligation at an academic medical center

Background: Use of an in situ epidural catheter has been suggested to be efficient to provide anesthesia for postpartum tubal ligation (PPTL). Reported epidural reactivation success rates vary from 74% to 92%. Predictors for reactivation failure include poor patient satisfaction with labor analgesia, increased delivery-to-reactivation time and the need for top-ups during labor. Some have suggested that this high failure rate precludes leaving the catheter in situ after delivery for subsequent reactivation attempts. In this study, we sought to evaluate the success rate of neuraxial techniques for PPTL and to determine if predictors of failure can be identified. Methods: After obtaining IRB approval, a retrospective chart review of patients undergoing PPTL after vaginal delivery from July 2010 to July 2016 was conducted using CPT codes, yielding 93 records for analysis. Demographic, obstetric and anesthetic data (labor analgesia administration, length of epidural catheter in epidural space, top-up requirements, time of catheter reactivation, final anesthetic technique and corresponding doses for spinal and epidural anesthesia) were obtained. Results: A total of 70 patients received labor neuraxial analgesia. Reactivation was attempted in 33 with a success rate of 66.7%. Patient height, epidural volume of local anesthetic and administered fentanyl dose were lower in the group that failed reactivation. Overall, spinal anesthesia was performed in 60 patients, with a success rate of 80%. Conclusions: Our observed rate of successful postpartum epidural reactivation for tubal ligation was lower than the range reported in the literature. Our success rates for both spinal anesthesia and epidural reactivation for PPTL were lower than the generally accepted rates of successful epidural and spinal anesthesia for cesarean delivery. This gap may reflect a lower level of motivation on behalf of both the patients and anesthesia providers to tolerate "imperfect" neuraxial anesthesia once fetal considerations are removed.

Risks and side-effects of intrathecal morphine combined with spinal anaesthesia: a meta-analysis

Intrathecal morphine is often used for postoperative analgesia after surgery. We performed a meta-analysis to obtain more detailed information on the frequency of side-effects in patients receiving intrathecal morphine in combination with spinal anaesthesia compared with placebo treated patients. We clustered the analysis to patients receiving placebo, less than morphine 0.3 mg (M < 0.3), or equal to or more than morphine 0.3 mg (M > or = 0.3) and calculated the risk ratios of morphine vs placebo. Twenty-eight studies investigating 46 morphine groups vs placebo were included. A total of 790 patients with intrathecal morphine and 524 patients who received placebo were analysed. Compared with placebo the lower dose of morphine resulted in an increase of nausea (RR 1.4, 95% CI 1.1-1.7), vomiting (RR 3.1, 95% CI 1.5-6.4) and pruritus (RR 1.8, 95% CI 1.4-2.2). The higher dose resulted in an increased risk ratio for pruritus (RR 5.0, 95% CI 2.9-8.6), but not nausea (RR 1.2, 95% CI 0.9-1.6) or vomiting (RR 1.3, 95% CI 0.9-1.9). Overall, intrathecal morphine did not increase respiratory depression. However, the higher dose of intrathecal morphine was associated with more episodes of respiratory depression (7/80) compared with the lower dose (2/247). Intrathecal morphine is associated with a mild increase in side-effects. With a dose < 0.3 mg we found there were no more episodes of respiratory depression than in placebo patients who received systemic opioid analgesia.

Comparison of spinal anesthesia with general anesthesia on morphine requirement after abdominal hysterectomy

PURPOSE

The aim of this study was to compare morphine consumption with patient-controlled analgesia (PCA) between spinal anesthesia (SA) (bupivacaine, morphine and fentanyl) and general anesthesia (GA) (sufentanil) after an abdominal hysterectomy.

METHODS

Forty women were randomly assigned to receive SA with bupivacaine 15 mg, 0.15 mg of intrathecal morphine and 15 microg of fentanyl or GA with sufentanil, both combined with PCA. The primary outcome was morphine consumption with the PCA device. The secondary outcomes were post-operative pain at rest and under stress on a visual analog scale, nausea, pruritus and respiratory depression on a standardized scale. Outcome measures were recorded at 6, 12, 18, 24 and 48 h post-anesthesia. The duration of post-anesthesia care unit (PACU) and hospital stay were recorded.

RESULTS

Patients in the SA group consumed at least two times less morphine at each time interval than the GA group: at 48 h, they used 19 +/- 17 vs. 81 +/- 31 mg (P<0.0001). Post-operative pain at rest was lower in the SA group until the 18th hour and under stress until the 48th. There was more sedation in the GA group until the 18th hour. Little difference was observed in the incidence of pruritus. Nausea was more intense at the 6th hour in the GA group. There was no difference in the respiratory rate. The duration of PACU stay was shorter for the SA group (52 +/- 9 vs. 73 +/- 11 min, P<0.0001) as was the duration of hospital stay (2.2 +/- 0.4 vs. 3.3 +/- 0.7 days, P=0.01).

CONCLUSIONS

It is concluded that intrathecal morphine 0.15 mg with 15 microg of fentanyl decreases post-operative pain and morphine consumption by PCA without increasing adverse reactions for women undergoing an abdominal hysterectomy.

Endogenous opiates and behavior: 2005

This paper is the 28th consecutive installment of the annual review of research concerning the endogenous opioid system, now spanning over a quarter-century of research. It summarizes papers published during 2005 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity, neurophysiology and transmitter release (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); immunological responses (Section 17).

An audit of analgesia after day case gynaecological laparoscopic surgery

An audit of patients' pain relief following day case gynaecological laparoscopic surgery was conducted to identify postoperative analgesic requirements. In this article the authors also look at the incidence of nausea and vomiting, length of hospital stay and recorded overnight admissions.

Opioid-related side-effects after intrathecal morphine: a prospective, randomized, double-blind dose-response study

BACKGROUND AND OBJECTIVE

The aim of this prospective, randomized, double-blind investigation was to assess the dose-effect characteristics of postoperative nausea and vomiting after intrathecal administration of small doses of morphine (from 0.015 to 0.25 mg) in opioid-naïve, non-surgical patients.

METHODS

With Ethic Committee approval and written informed consent 144 opioid-naïve patients suffering from non-cancerous chronic back-pain, and receiving intrathecal morphine as diagnostic test for their chronic pain, were randomly allocated to receive intrathecal injection of 0.015 mg (Group I, n=25), 0.03 mg (Group II, n=30), 0.06 mg (Group III, n=31) or 0.25 mg (Group IV, n=33) morphine. The control group consisted in 25 further patients not included in the dose-effect study and receiving a placebo injection of normal saline in the interspinous ligament. A blinded observer recorded the occurrence of pruritus, nausea, vomiting, urinary retention and respiratory depression (respiratory rate<6 bpm) at 2, 4 and 24 h after injection.

RESULTS

Clinically significant pain relief was observed in all patients receiving intrathecal morphine but only six patients (25%) of the control group (P=0.0005). The incidence of pruritus was lower in patients of Groups III (6%) and IV (3%) than in Groups I (12%) and II (20%) (P=0.002). The incidence of nausea and vomiting was higher at 2- and 4-h observation times, and decreased 24 h after intrathecal injection. Surprisingly, nausea was more frequent in Groups I (56%) and II (50%) than in Groups III (33%) and IV (24%) (P=0.0005). Vomiting was higher in patients receiving morphine than in control group, but without differences among the four doses. No urinary retention was observed in the control group, while 2 h after intrathecal injection urinary retention was observed in 20-40% of cases, and decreased to less than 10% 24 h after spinal injection without differences among the four doses.

CONCLUSIONS

The onset and incidence of minor opioid-related side-effects after intrathecal morphine administration do not depend on its dose, occurring with even very small doses of morphine. Accordingly, they can be considered as a patient-dependent effect of the drug, suggesting the presence of a primary dose-independent excitatory component that might be related to the theory of the bimodal activation of opioid receptors. The very low incidence major respiratory depression prevents us from drawing any conclusion about the dose-effect relationship for this side-effect, and further properly powered studies should be advocated to evaluate major respiratory depression after spinal morphine.

Postoperative Epidural Morphine for Postpartum Tubal Ligation Analgesia

Women undergoing postoperative postpartum tubal ligation (PPTL) often experience considerable pain. We hypothesized that epidural morphine, as part of a multi-modal analgesic regimen, would decrease postoperative pain and the need for systemic analgesia after PPTL. In a double-blinded study, patients were randomized to receive epidural saline or morphine 2 mg, 3 mg, or 4 mg after epidural anesthesia for PPTL. Postoperatively, ibuprofen 600 mg was administered every 6 h and patients could request acetaminophen 325 mg/hydrocodone 10 mg. The primary outcome variable was time to first request for supplemental analgesia. Verbal rating scores for pain and the incidence and severity of side effects were recorded for 24 h. Morphine group subjects requested supplemental analgesia later and received fewer doses compared with the saline group subjects. Peak cramping and incisional verbal rating scores for pain and the area under the verbal rating scores for pain x time curve for cramping pain were less after epidural morphine compared with saline, but there were no differences among morphine groups. Nausea, vomiting, and pruritus occurred more often in all morphine groups and subjects who received morphine 4 mg required treatment for these side effects more frequently than the saline or morphine 2 mg groups. In conclusion, epidural morphine 2 mg as part of a multi-modal analgesic regimen improved analgesia and decreased the need for supplemental analgesics after PPTL. The need to treat side effects with morphine 2 mg was not increased compared to a regimen of oral acetaminophen/opioid/nonsteroidal antiinflammatory analgesics.