Efficacy of a low-dose spinal morphine with bupivacaine for postoperative analgesia in children undergoing hypospadias repair

Effects of 5 µg/kg intrathecal morphine for postoperative analgesia in pediatric patients undergoing major surgery

BACKGROUND

The effects and analgesic adequacy of intrathecal morphine (ITM) administration have been studied less frequently than other regional analgesia techniques in pediatric surgical procedures.

OBJECTIVE

To evaluate the efficacy and adverse event rate of 5 µg/kg ITM administration for postoperative analgesia according to age group.

METHODS

We retrospectively evaluated the medical records of patients who underwent major pediatric surgery and were administered ITM for postoperative analgesia. Patients were divided into three age groups: ≤ 5 years (group I), 5.1-13 years (group II) and > 13 years (group III). All patients received ITM 5 µg/kg (max 300 μg) through the L_4-5 or L₅-S₁ interspace. Postoperative pain (modified pediatric objective pain score > 4), need for rescue analgesics, sleep interruption due to pain, sedation (Ramsay sedation scale score > 3), opioid-related postoperative adverse events (at 0, 4, 8, 12, and 24 h after intervention), hemodynamic data and nurse satisfaction with the analgesic method were compared between groups.

RESULTS

The analysis included 100 children (47 girls, 9 ± 5.4 years). Groups were similar regarding postoperative rescue analgesia consumption and sleep interruption (p = 0.238, p = 0.958), 96% of the children did not require rescue analgesia, and sleep interruption was not observed in 97%. Postoperative adverse events were pruritus in 14 and nausea/vomiting in 9 patients (p = 0.052). Overall, nurses were satisfied or very satisfied in 99% of the cases.

CONCLUSION

Administration of 5 µg/kg ITM can be used for postoperative analgesia in pediatric surgery in all age groups, with no severe adverse events and high nurse satisfaction with analgesic management.

Pain outcomes in children who received intrathecal vs intravenous opioids for pain control following major urologic surgery: a retrospective review

BACKGROUND

Intrathecal (IT) opioid administration has been associated with postoperative benefits including reduced pain and opioid use in children. However, the postoperative benefits and risks of IT opioid administration during major urologic surgery in children remain unclear.

AIM

The aim of this study was to compare postoperative pain and adverse event outcomes among children who received IT vs intravenous (IV) opioids during major urologic surgery.

METHODS

We reviewed the medical records of children 3-17 years of age who underwent ureteroneocystostomy or pyeloplasty between 2006 and 2012. Electronically captured anesthetic and surgical data, postanesthesia care recovery unit (PACU) and nursing flowsheets, and daily progress notes through hospital discharge were reviewed. Analgesic techniques (i.e., IT or IV patient/nurse controlled opioids), all analgesic drugs and doses were recorded. Outcome measures included pain scores, need for rescue analgesics, opioid-related adverse events, and their treatments.

RESULTS

Seventy-seven children received IT opioids and 51 received IV opioids. More children in the IV group required rescue analgesics and had higher pain scores at PACU discharge. Children in the IV group required rescue opioids more frequently than the IT group from 0 to 8 h and 8 to 16 h after PACU discharge, but rates were similar by 16-24 h 70% of children in IT group transitioned directly to oral opioids. Seven IT placements were considered as failed due to early need for rescue opioids. Four (8%) of the IV group and seven (9%) of the IT group experienced oxygen desaturation. Two of these, both in IT group required naloxone and one was admitted to ICU for observation. The IT group experienced a higher incidence of pruritus, constipation and hypotension.

CONCLUSION

We observed better postoperative pain control in children who received IT vs IV opioids for the first 16 h with no discernible difference thereafter. The intrathecal group experienced higher incidences of pruritus, constipation, and hypotension.

Single-dose intra-articular bupivacaine plus morphine after knee arthroscopic surgery: a meta-analysis of randomised placebo-controlled studies

OBJECTIVES

To evaluate the efficacy and safety of single-dose intra-articular bupivacaine plus morphine after knee arthroscopic surgery.

DESIGN

Meta-analysis.

DATA SOURCES AND STUDY ELIGIBILITY CRITERIA

A comprehensive literature search, using Medline (1966-2014), the Cochrane Central Register of Controlled Trials and Embase databases, was conducted to identify randomised placebo-controlled trials that used a combination of single-dose intra-articular bupivacaine and morphine for postoperative pain relief.

RESULTS

12 articles were included in this meta-analysis. The mean visual analogue scale (VAS) scores of the bupivacaine plus morphine group were significantly lower than those of the placebo group (weighted mean difference (WMD) -1.75; 95% CI -2.16 to -1.33; p<0.001). The VAS scores at the last follow-up time point (last VAS scores) of the bupivacaine plus morphine group were also significantly lower than those of the placebo group (WMD -1.46; 95% CI -1.63 to -1.29; p<0.001). The number of patients requiring supplementary analgesia was also significantly reduced (RR 0.60; 95% CI 0.39 to 0.93; p=0.02), while there was no significant difference in the time to first analgesic request (WMD 3.46; 95% CI -1.81 to 8.72; p=0.20) or short-term side effects (RR 1.67; 95% CI 0.65 to 4.26; p=0.29).

CONCLUSIONS

The administration of single-dose intra-articular bupivacaine plus morphine after knee arthroscopic surgery is effective for pain relief, and its short-term side effects remain similar to saline placebo.

Neuraxial analgesia in neonates and infants: a review of clinical and preclinical strategies for the development of safety and efficacy data

Neuraxial drugs provide robust pain control, have the potential to improve outcomes, and are an important component of the perioperative care of children. Opioids or clonidine improves analgesia when added to perioperative epidural infusions; analgesia is significantly prolonged by the addition of clonidine, ketamine, neostigmine, or tramadol to single-shot caudal injections of local anesthetic; and neonatal intrathecal anesthesia/analgesia is increasing in some centers. However, it is difficult to determine the relative risk-benefit of different techniques and drugs without detailed and sensitive data related to analgesia requirements, side effects, and follow-up. Current data related to benefits and complications in neonates and infants are summarized, but variability in current neuraxial drug use reflects the relative lack of high-quality evidence. Recent preclinical reports of adverse effects of general anesthetics on the developing brain have increased awareness of the potential benefit of neuraxial anesthesia/analgesia to avoid or reduce general anesthetic dose requirements. However, the developing spinal cord is also vulnerable to drug-related toxicity, and although there are well-established preclinical models and criteria for assessing spinal cord toxicity in adult animals, until recently there had been no systematic evaluation during early life. Therefore, in the second half of this review, we present preclinical data evaluating age-dependent changes in the pharmacodynamic response to different spinal analgesics, and recent studies evaluating spinal toxicity in specific developmental models. Finally, we advocate use of neuraxial drugs with the widest demonstrable safety margin and suggest minimum standards for preclinical evaluation before adoption of new analgesics or preparations into routine clinical practice.