Addition of midazolam to continuous postoperative epidural bupivacaine infusion reduces requirement for rescue analgesia in children undergoing upper abdominal and flank surgery

A double-blinded randomized control trial to compare the duration of analgesia using morphine, clonidine, or dexmedetomidine as adjuvants to ropivacaine in caudal anesthesia in children undergoing infraumbilical surgeries

Background and Aims

Adjuvants added to the caudal block prolong the duration of analgesia. In a developing country with economic constraints, the choice of an adjuvant will be the medication with a longer duration of analgesia, a favorable side-effect profile, and the least expensive option. We wished to study the duration of postoperative analgesia afforded by three adjuvants: morphine, clonidine, and dexmedetomidine, at doses wherein minimal or nil adverse effects would be attributed to the adjuvant. The primary objective of the current study is to compare the duration of postoperative analgesia with morphine, clonidine, or dexmedetomidine as adjuvants to 0.2% ropivacaine in a for caudal block, in children undergoing elective abdominal, urogenital, and lower limb surgeries. The secondary objectives are (a) to study the total analgesic requirement during the first 24 hours after surgery and (b) to compare the incidence of complications among the three groups.

Material and Methods

Sixty-three children aged 1-6 years, belonging to American Society of Anesthesia (ASA) physical status I, II, and scheduled to undergo elective infraumbilical surgeries, were enrolled in the study. The children were randomly assigned to one of three groups: Group D received a caudal block with dexmedetomidine 1 μg/kg, Group M received morphine 30 μg/kg, and Group C received clonidine 1.5 μg/kg. All groups also received 0.2% ropivacaine (1-1.25 ml/kg) as part of the caudal block. The duration of analgesia, total analgesic requirements during the first 24 hours after the surgery, and the incidence of complications in the three groups were monitored by a pain nurse who was blinded to the study allocation.

Results

The three groups were comparable with respect to age, sex, weight, and duration of surgery. The median time taken for the first rescue analgesic in the dexmedetomidine group was 380 minutes, in the clonidine group was 360 minutes, and in the morphine group was 405 minutes. Though the morphine group had a longer duration of analgesia, it was not statistically significant (P = 0.843). The total perioperative opioids used and side effects were similar among the three groups. There were no episodes of intraoperative bradycardia noted in Groups D, M, and C. However, one patient in Group D required treatment for bradycardia in the postanesthesia care unit. In terms of intraoperative hypotension, 10 patients (43.5%) in Group D, 5 patients (27.8%) in Group C, and 5 patients (22.7%) in Group M required treatment, but this difference was not statistically significant (P = 0.299). There was no significant difference observed in the time to awakening after the anesthesia among the three groups. Postoperative nausea and vomiting were noted in five patients (21.7%) in Group D, one patient (5.6%) in Group C, and four patients (18.2%) in Group M (P = 0.382). One patient in Group M had a sedation score of 5 and required 4 hours of supplemental oxygen via face mask in the ward. Additionally, one patient in Group D reported numbness in both feet lasting 12 hours with spontaneous resolution. While a significant number of patients in all three study groups experienced urinary retention, no patient reported pruritus in the ward.

Conclusion

Caudal administration of morphine, dexmedetomidine, and clonidine in children undergoing infraumbilical surgery resulted in an equivalent duration of analgesia.

Effect of Combined Epidural Morphine and Midazolam on Postoperative Pain in Patients Undergoing Major Abdominal Cancer Surgery

OBJECTIVE

The objective was to compare analgesic effect of combined epidural morphine-midazolam with either drug alone on postoperative pain in patients undergoing major abdominal cancer surgery.

MATERIALS AND METHODS

Eighty-four patients were allocated in prospective randomized double-blind study to receive epidural analgesia. Patients received 5 mg morphine in morphine (Mor) group, 5 mg midazolam in midazolam (Mid) group, 5 mg morphine + 5 mg midazolam in morphine-midazolam (MM) group, 0.25% bupivacaine was added to injected solution with same volume in all groups. All groups were compared with time of first analgesic request, total analgesic consumption, number of epidural doses, postoperative Visual Analog Scale score, and adverse events.

RESULTS

Time of first analgesic request was 4 to 8 hours in Mid versus 12 to 23 and 14 to 24 hours in Mor and MM groups, respectively, with significant difference between Mid versus Mor ( P <0.001), Mid versus MM ( P <0.001), and Mor versus MM groups ( P <0.031). Analgesic consumption was more in Mid than Mor and MM groups, with significant difference between Mid versus Mor ( P <0.008), Mid versus MM ( P <0.001), with no significant difference between Mor and MM groups ( P <0.6). The number of epidural doses in Mid was 1 to 3 versus 1 to 3, and 1 to 2 in Mor and MM groups, respectively, with significant difference between Mid versus Mor ( P <0.025), Mid versus MM ( P <0.004), with no significant difference between Mor and MM groups ( P =1.0).

CONCLUSIONS

Addition of midazolam to epidural morphine prolonged time of first analgesic request and decreased total analgesic consumption.

Guidelines for Opioid Prescribing in Children and Adolescents After Surgery: An Expert Panel Opinion

IMPORTANCE

Opioids are frequently prescribed to children and adolescents after surgery. Prescription opioid misuse is associated with high-risk behavior in youth. Evidence-based guidelines for opioid prescribing practices in children are lacking.

OBJECTIVE

To assemble a multidisciplinary team of health care experts and leaders in opioid stewardship, review current literature regarding opioid use and risks unique to pediatric populations, and develop a broad framework for evidence-based opioid prescribing guidelines for children who require surgery.

EVIDENCE REVIEW

Reviews of relevant literature were performed including all English-language articles published from January 1, 1988, to February 28, 2019, found via searches of the PubMed (MEDLINE), CINAHL, Embase, and Cochrane databases. Pediatric was defined as children younger than 18 years. Animal and experimental studies, case reports, review articles, and editorials were excluded. Selected articles were graded using tools from the Oxford Centre for Evidence-based Medicine 2011 levels of evidence. The Appraisal of Guidelines for Research & Evaluation (AGREE) II instrument was applied throughout guideline creation. Consensus was determined using a modified Delphi technique.

FINDINGS

Overall, 14 574 articles were screened for inclusion, with 217 unique articles included for qualitative synthesis. Twenty guideline statements were generated from a 2-day in-person meeting and subsequently reviewed, edited, and endorsed externally by pediatric surgical specialists, the American Pediatric Surgery Association Board of Governors, the American Academy of Pediatrics Section on Surgery Executive Committee, and the American College of Surgeons Board of Regents. Review of the literature and guideline statements underscored 3 primary themes: (1) health care professionals caring for children who require surgery must recognize the risks of opioid misuse associated with prescription opioids, (2) nonopioid analgesic use should be optimized in the perioperative period, and (3) patient and family education regarding perioperative pain management and safe opioid use practices must occur both before and after surgery.

CONCLUSIONS AND RELEVANCE

These are the first opioid-prescribing guidelines to address the unique needs of children who require surgery. Health care professionals caring for children and adolescents in the perioperative period should optimize pain management and minimize risks associated with opioid use by engaging patients and families in opioid stewardship efforts.

Efficacy of Adding Midazolam to Bupivacaine for Transversus Abdominis Plane Block on Postoperative Analgesia after Hysterectomy: A Randomized Controlled Study

Background and Aim:

Different adjuncts have been utilized to promote the quality and prolong the duration of local anesthetics for a variety of regional block techniques. This study aimed to assess the effects of midazolam coadministered with bupivacaine in transversus abdominis plane (TAP) block on the 24-h morphine consumption, the postoperative analgesia duration and adverse effects.

Settings and Design:

A prospective, randomized, controlled double-blind trial that was carried out at a university hospital.

Patients and Methods:

Eighty-two females subjected to open total abdominal hysterectomy under general anesthesia were involved in this trial. Participants were allocated randomly to either of two groups (41 each). Control group: received TAP block with 20 mL of 0.25% bupivacaine or midazolam group: received TAP block using the same volume of bupivacaine plus 50 μg/kg midazolam/side. Postoperative cumulative 24-h morphine consumption, analgesia duration, pain score, sedation score, and adverse events were recorded.

Statistical Analysis:

Student's t-test, Mann–Whitney U-test, and Chi-square test were used.

Results:

Patients in the midazolam group had a lower cumulative 24-h morphine consumption [median doses (interquartile range): 15 (10–19.50) mg compared to 25 (17.50–37) mg, P < 0.001], lower postoperative pain score at rest at the 4^th, 6^th, and 12^th h (P = 0.01, 0.02, and 0.02, respectively) and on movement at 2, 4, 6, and 12 h (P < 0.001), longer time till the first postoperative demand for rescue analgesia (430.11 ± 63.02 min) compared to 327.78 ± 61.99 min (P < 0.001), and less sedation, nausea and/or vomiting, and pruritus.

Conclusions:

Adding midazolam as a bupivacaine adjuvant for TAP block reduces the 24-h morphine consumption, extends the postoperative analgesia duration, and decreases the incidence of adverse effects following abdominal hysterectomy.

Sedation with dexmedetomidine prolongs the analgesic duration of brachial plexus block: a randomised controlled trial

PURPOSE

Dexmedetomidine, an alpha 2 receptor agonist, prolongs nerve block duration when administered in conjunction with peripheral nerve blocks. We hypothesised that sedation with dexmedetomidine could also significantly prolong the analgesic duration of brachial plexus block (BPB) during orthopaedic surgery on the upper extremities.

MATERIALS AND METHODS

One hundred and two patients received upper extremity surgery under BPB. The patients were randomly sedated with dexmedetomidine (D group) or midazolam (M group) following BPB using 25 mL of local anaesthetics (1:1 mixture of 1% lidocaine and 0.75% ropivacaine). Adequate sedation was evaluated with the modified Ramsay Sedation Scale. Primary outcome was measured as the time the patient first requested analgesic via a patient-controlled analgesia device. Total opioid consumption during the first 24 post-operative hours was also measured as secondary outcomes.

RESULTS

Time to first request for analgesia (mean ± standard deviation) was significantly longer in the D group (616.9 ± 158.2 min) than in the M group (443.7 ± 127.2 min) (P < 0.001, Mean difference [95% CI] 173.2 [114.8-231.5] min). Total opioid consumption were significantly lower in the D group (fentanyl equivalent, 280.0 μg [171.3;374.0] vs. 363.9 μg [208.3;570.1], P = 0.01). Although patients in the D group showed deeper sedation over time (P < 0.001), PACU stay time was only slightly extended in D group (5.2 [1.2-9.2] min). Perioperative complications did not differ in the two groups.

CONCLUSION

Sedation with dexmedetomidine not only prolongs analgesic duration of BPB, but also reduces total opioid consumption during the first 24 post-operative hours.

Effect of adding midazolam to bupivacaine during rectus sheath block: a randomised controlled trial

BACKGROUND

Various adjuvants have been tried to improve quality and increase duration of local anaesthetics during various nerve blocks. We aimed to evaluate the effect of adding midazolam to bupivacaine on rectus sheath (RS) block in patients undergoing umbilical or epigastric hernia repair.

METHODS

In all, 60 adult patients were divided into two equal groups, each group included 30 patients. Group I received 20 ml of bupivacaine hydrochloride 0.25% + midazolam 50 μg/kg in 2 ml saline 0.9% (Midazolam group, n = 30), whereas Group II received 20 ml of bupivacaine hydrochloride 0.25% + 2 ml saline (Control group, n = 30) for RS block on each side. The primary outcome was post-operative 48 h morphine consumption, whereas secondary outcomes included analgesia duration, post-operative pain, as evaluated by visual analogue scale (VAS) for pain scoring at 1, 2, 6, 12, 24 and 48 h post-operatively, reported post-operative nausea and or vomiting (PONV), somnolence or any adverse drug reactions.

RESULTS

The current study showed that addition of midazolam to bupivacaine for RS blockade provided good analgesia as evidenced by a statistically significant less morphine consumption in the post-operative 48 h [11.2 (5.3-18.3) vs. 25.9 (15.2-31.0) mg, P = 0.002], longer duration of analgesia, lower VAS during post-operative 48 h, lower incidence of PONV, somnolence and pruritus.

CONCLUSION

Midazolam addition to bupivacaine for RS blockade provided adjuvant analgesia as supported by less morphine consumption, longer duration of analgesia, and lower VAS score.

Perioperative epidural analgesia in children undergoing major abdominal tumor surgery--a single center experience

PURPOSE

The purpose of this study was to assess the use of continuous epidural analgesia in pediatric patients undergoing major abdominal tumor surgery.

METHODS

Children undergoing major abdominal tumor surgery at our institution between 2008 and 2012 (n=40) received continuous epidural analgesia via an epidural catheter. Surgical trauma scores, pain scores, and clinical data of the children were compared to a pair-matched historical control group operated on between 2002 and 2007 without epidural analgesia.

RESULTS

Pain levels in the study group on day 1 and 3 after surgery were lower compared to the control group. The differences did, however, not reach statistical significance (p=0.15 and 0.09). Children in the study group received significantly fewer additional doses of piritramide or morphine (45% versus 82%, p<0.001). Despite significantly higher surgical trauma scores in the study group (p=0.018), there were no statistical differences regarding clinical parameters, such as mechanical ventilation time, time on intensive care unit, and total hospital stay. There were no catheter-related complications.

CONCLUSIONS

Continuous epidural analgesia is beneficial for children undergoing complex abdominal tumor surgery with regard to pain levels, postoperative recovery, and general clinical course. Expertise of the managing team, a careful patient selection, and a continuous quality assessment are essential for success.

Quality of lidocaine analgesia with and without midazolam for intravenous regional anesthesia

PURPOSE

Midazolam has analgesic effects mediated by gamma aminobutyric acid-A receptors. This study was designed to evaluate the effect of midazolam on anesthesia and analgesia quality when added to lidocaine for intravenous regional anesthesia (IVRA).

METHODS

Forty patients undergoing hand surgery were randomly assigned to two groups to receive IVRA. The control group received 3 mg/kg lidocaine 2% w/v diluted with saline to a total volume of 40 ml, and the midazolam group received an additional 50 μg/kg midazolam. Sensory and motor block onset and recovery times, tourniquet pain, intraoperative analgesic requirements, sedation, and anesthesia quality were recorded. Postoperative pain and sedation scores, time to first analgesic requirements, analgesic use in the first 24 h, and side effects were noted.

RESULTS

Sensory and motor block onset and recovery times did not differ significantly between groups. Tourniquet pain scores were lower at 10, 15, 20, and 30 min (P < 0.0001) in the midazolam group. Three (15%) patients in the midazolam group required fentanyl for tourniquet pain compared with thirteen (65%) patients in the control group (P = 0.02). Patients in both groups received fentanyl once. Midazolam group showed that significantly less patients required diclofenac for postoperative analgesia (P < 0.01) and analgesic-free period during first postoperative 24 h was significantly longer (726.8 ± 662.8 min vs. 91.0 ± 35.9 min, P < 0.0001). Postoperative pain scores were lower (P < 0.0001) and sedation scores higher (P < 0.05) for the first 2 h in the midazolam group.

CONCLUSION

Addition of midazolam to lidocaine for IVRA improves anesthesia quality and enhances intraoperative and postoperative analgesia without causing side effects.

Intravenous dexmedetomidine, but not midazolam, prolongs bupivacaine spinal anesthesia

PURPOSE

Midazolam has only sedative properties. However, dexmedetomidine has both analgesic and sedative properties that may prolong the duration of sensory and motor block obtained with spinal anesthesia. This study was designed to compare intravenous dexmedetomidine with midazolam and placebo on spinal block duration, analgesia, and sedation in patients undergoing transurethral resection of the prostate.

METHODS

In this double-blind randomized placebo-controlled trial, 75 American Society of Anesthesiologists' I and II patients received dexmedetomidine 0.5 microg . kg(-1), midazolam 0.05 mg . kg(-1), or saline intravenously before spinal anesthesia with bupivacaine 0.5% 15 mg (n = 25 per group). The maximum upper level of sensory block and sensory and motor regression times were recorded. Postoperative analgesic requirements and sedation were also recorded.

RESULTS

Sensory block was higher with dexmedetomidine (T 4.6 +/- 0.6) than with midazolam (T 6.4 +/- 0.9; P < 0.001) or saline (T 6.4 +/- 0.8; P < 0.001). Time for sensory regression of two dermatomes was 145 +/- 26 min in the dexmedetomidine group, longer (P < 0.001) than in the midazolam (106 +/- 39 min) or the saline (97 +/- 27 min) groups. Duration of motor block was similar in all groups. Dexmedetomidine also increased the time to first request for postoperative analgesia (P < 0.01 compared with midazolam and saline) and decreased analgesic requirements (P < 0.05). The maximum Ramsay sedation score was greater in the dexmedetomidine and midazolam groups than in the saline group (P < 0.001).

CONCLUSION

Intravenous dexmedetomidine, but not midazolam, prolonged spinal bupivacaine sensory blockade. It also provided sedation and additional analgesia.