Use of the mixed agonist–antagonist nalbuphine in opioid based analgesia

Exploring nalbuphine loaded chitosan nanoparticles for effective pain management through intranasal administration: a comparative study

BACKGROUND

Intranasal drug delivery shows potential for brain access via olfactory and trigeminal routes.

PURPOSE

This work aimed to ensure brain availability of nalbuphine via the nasal route.

METHOD

Chitosan based nanoparticles loaded with nalbuphine were successfully prepared using ionic gelation method and characterised.

RESULT

SEM results revealed that the nanoparticles were spherical in shape, with an average size of 192.4 ± 11.6 nm. Zeta potential and entrapment efficiency was found 32.8 mV and 88.43 ± 7.75%, respectively. The X-ray diffractometry and DSC results unravel a profound understanding on the physical and thermal characteristics. The in-vitro release of nalbuphine from the nanoparticles was biphasic, with an initial burst release followed by a slow-release profile. In-vitro cell study on HEK-293 cells and microscopic images of brain tissue confirmed the safety profile of formulation. In-vivo efficacy studies on animal confirmed the effectiveness of developed intranasal formulation as compared to the standard therapy. The in-vivo pharmacokinetic studies showed that the prepared nanoparticles were able to efficiently deliver nalbuphine to the brain in comparison to the other body organs. Gamma scintigraphy images showed retention of the drug in the brain. Furthermore, the efficacy studies confirmed that the nanoparticles were found significantly more effective than the marketed formulation in pain management.

The effect of nalbuphine on prevention of emergence delirium in children: a systematic review with meta-analysis

BACKGROUND

Emergence delirium remains a major postoperative concern for children undergoing surgery. Nalbuphine is a synthetic mixed agonist-antagonist opioid, which is believed to reduce the incidence of emergence delirium in children. The primary objective was to examine the effect of nalbuphine on emergence delirium in children undergoing surgery.

METHODS

Databases of MEDLINE, EMBASE, and CENTRAL were searched from their starting dates until April 2023. Randomized Clinical Trials (RCT) and observational studies comparing nalbuphine and control in children undergoing surgery were included.

RESULTS

Eight studies (n = 1466 patients) were eligible for inclusion of data analysis. Compared to the control, our pooled data showed that the nalbuphine group was associated with lower incidence of emergence delirium (RR = 0.38, 95% CI [0.30, 0.47], p < 0.001) and reduced postoperative pain scores (MD = -0.98, 95% CI [-1.92, -0.04], p = 0.04).

CONCLUSIONS

This review showed the administration of nalbuphine is associated with significant decrease in the incidence of emergence delirium and postoperative pain scores among children undergoing surgery. However, due to limited sample size, high degree of heterogeneity and low level of evidence, future adequately powered trials are warranted to explore the efficacy of nalbuphine on emergence delirium among the pediatric population.

Assessment of the Efficacy of Nalbuphine as an Adjuvant to Intrathecal Bupivacaine in Endoscopic Urological Surgeries for the Prolongation of Postoperative Analgesia

Background In anaesthesiology, intrathecal drugs play pivotal roles in spinal anaesthesia. Despite their ability to induce a high sensory block, bupivacaine alone may not be adequate for postoperative analgesia. It often requires a substantial dose of postoperative rescue analgesia to manage pain effectively. Thus, we studied the efficacy of nalbuphine 1.5 mg injected intrathecally as an adjuvant in endoscopic urological surgery. Materials and methods Sixty patients undergoing endoscopic urological surgery were equally divided into two study groups: group B (injection 0.5% hyperbaric bupivacaine 15 mg (3 ml) plus sterile NS 0.15 ml) and group N (injection 0.5% hyperbaric bupivacaine 15 mg (3 ml)+nalbuphine 1.5 mg (0.15 ml)). The first appearance of the sensory and motor blockages and duration required to attain complete sensory and motor threshold was noted. All vitals were recorded. After surgery, it was recorded when the patient first needed rescue analgesia (injection paracetamol 1 gm IV). Any adverse effects were recorded and addressed. The statistical analysis was conducted using IBM SPSS Statistics for Windows, V. 22.0 (IBM Corp., Armonk, NY), with p<0.05 indicating significance in both groups' operations. Results Intrathecal nalbuphine as an adjuvant caused an earlier onset of sensory and motor inhibition, delayed two-segment regression, and prolonged postoperative anaesthesia. The control group experienced sensory block at 3.33±0.61 minutes, while the nalbuphine group had a mean onset of 2.66±0.92 minutes (p=0.001). The patient who received nalbuphine had a mean regression time of 119.60±14.549 minutes, whereas the bupivacaine group had a mean regression time of 88.43±17.196 minutes. Group N had a considerably longer duration of postoperative analgesia, lasting 264.97 minutes, compared to group B's 198.50 minutes (p<0.001). Intrathecal nalbuphine did not influence vital indicators such as heart rate, respiration rate, and oxygen saturation. Conclusion To conclude, endoscopic urological surgery patients who received a subarachnoid block with 1.5 mg (0.15 ml) of nalbuphine hydrochloride with 0.5% hyperbaric bupivacaine 15 mg (3 ml) had longer postoperative pain relief than those who received 3 ml of intrathecal bupivacaine (15 mg). Urinary retention and pruritus were absent. Intrathecal nalbuphine with hyperbaric 0.5% bupivacaine is deemed safe with minimal side effects in endoscopic urology surgery.

Pharmacokinetics of nalbuphine administered intravenously and subcutaneously in goats (Capra aegagrus hircus)

The purpose of this study was to evaluate the pharmacokinetics (PK) of intravenously (IV) and subcutaneously (SC) administered nalbuphine in domestic goats. Nalbuphine hydrochloride was administered at 0.8 mg/kg for both IV and SC routes in six goats with a minimum of 10-day washout period between sample collection phases. Eighteen plasma samples were collected over a 36-hour period, analyzed using reverse phase high-performance liquid chromatography (HPLC). Plasma data were analyzed using compartmental and noncompartmental approaches. Following IV nalbuphine administration, elimination half-life, area under the plasma concentration time curve from time 0 to infinity (AUC0 - ∞), concentration at time zero (C0), and total body clearance were 120.4 ± 39.1 (min-1 ± SD), 17311.01 ± 7227.32 (min·ng·mL-1 ± SD), 675.6 ± 337.13 (ng·mL-1 ± SD), and 44.5 ± 13.8 (mL·min-1·kg-1 ± SD), respectively. After SC nalbuphine administration, elimination half-life, area under the plasma concentration time curve from time 0 to infinity (AUC0 - ∞), and maximum plasma drug concentration were 129 ± 52.9 (min-1 ± SD), 20826.5 ± 14376.2 (min·ng·mL-1), and 368.03 ± 503.78 (ng·mL-1). Calculated bioavailability for the SC route was 138 ± 126 (% ± SD). Nalbuphine in goats is characterized by rapid elimination and high subcutaneous bioavailability and may be a safe analgesic opioid option in goats in the future.

Optimal Post-Operative Nalbuphine Dose Regimen: A Randomized Controlled Trial in Patients with Laparoscopic Cholecystectomy

Background and Objectives: Optimal opioid analgesia is an excellent analgesia that does not present unexpected adverse effects. Nalbuphine, acting on the opioid receptor as a partial mu antagonist and kappa agonist, is considered a suitable option for patients undergoing laparoscopic surgery. Therefore, we aim to investigate the appropriate dosage of nalbuphine for post-operative pain management in patients with laparoscopic cholecystectomy. Materials and Methods: Patients were randomly categorized into low, medium, and high nalbuphine groups. In each group, a patient control device for post-operative pain control was programed with a low (0.05 mg/kg), medium (0.10 mg/kg), or high (0.20 mg/kg) nalbuphine dose as a loading dose and each bolus dose with a lockout interval of 7 min and without background infusion. Primary and secondary outcomes included the post-operative pain scale and nalbuphine consumption, and episodes of post-operative opioid-related adverse events and satisfactory scores. Results: The low-dosage group presented a higher initial self-reported pain score in comparison to the other two groups for the two hours post-op (p = 0.039) but presented lower nalbuphine consumption than the other two groups for four hours post-op (p = 0.047). There was no significant difference in the analysis of the satisfactory score and adverse events. Conclusions: An appropriate administration of nalbuphine could be 0.1 to 0.2 mg/kg at the initial four hours; this formula could be modified to a lower dosage (0.05 mg/kg) in the post-operative management of laparoscopic cholecystectomy.

Safety and Efficacy of Oral Nalbuphine on Postoperative Pain in Hemorrhoidectomy Patients: A Randomized, Double-blind, Placebo-controlled, Pivotal Trial

OBJECTIVES

Severe postoperative pain requiring opioid treatment has been reported in 20% to 40% of hemorrhoidectomy patients. Compared with morphine, nalbuphine offers better hemodynamic stability, a lower risk of respiratory depression, and a lower potential for addiction. Nalbuphine was developed from the intravenous form into an oral form (PHN131) to alleviate moderate-to-severe pain.

MATERIALS AND METHODS

A randomized, double-blind, placebo-controlled, multiple-dose, parallel-design trial was conducted to evaluate the safety and efficacy of PHN131 in patients undergoing hemorrhoidectomy. Eligible patients were randomly assigned to receive either PHN131 soft capsules containing nalbuphine hydrochloride 60 mg or placebo capsules. Intramuscular diclofenac was the rescue analgesic. Pain was measured by the area under the curve of mean Visual Analog Scale pain intensity scores.

RESULTS

Visual Analog Scale results in patients receiving PHN131 were significantly lower than placebo group scores through 48 hours postoperatively (149.2±75.52 vs. 179.6±65.97; P =0.0301). According to Brief Pain Inventory Short-Form scores, the impact of pain on quality of life was significantly smaller for the PHN131 group than for the placebo group. Time to the first use of diclofenac postoperatively was significantly longer in the PHN131 group than in the placebo group. The cumulative dosage of diclofenac in the PHN131 group was only around half of that in the placebo group ( P <0.0001). Drug-related adverse events were mild-to-moderate and resolved by the treatment end. No drug-related severe adverse events were observed.

DISCUSSION

Our findings demonstrate that PHN131 is effective and well-tolerated in the treatment of moderate-to-severe post hemorrhoidectomy pain and may provide another option for patients to control their pain.

A Comparative Study of Intrathecal Fentanyl and Nalbuphine as an Adjuvant to Hyperbaric Bupivacaine for Spinal Anesthesia in Lower Limb Orthopedic Surgeries: A Prospective, Double-Blind, Randomized Controlled Study

BACKGROUND

Spinal anaesthesia is the most commonly used technique for lower limb orthopaedic surgeries as it is economical and easy to administer. Opioids as adjuvants to local anaesthetics during spinal anaesthesia have played a vital role in reducing post-operative pain qualitatively and effectively.

METHODS

This prospective randomised study was conducted on 100 patients divided into two groups scheduled for lower limb orthopaedic surgeries. Group bupivacaine fentanyl (BF) received 25 mcg of fentanyl with 15 mg of bupivacaine and Group bupivacaine nalbuphine (BN) received 1 mg of nalbuphine and 15 mg of 0.5% bupivacaine. The aim of the study was to compare the analgesic efficacy of intrathecal fentanyl and nalbuphine as an adjuvant to hyperbaric bupivacaine for spinal anaesthesia. Duration of effective analgesia, haemodynamic parameters, onset and duration of sensory and motor block, adverse effects, and visual analogue scale (VAS) score were assessed.

RESULTS

Duration of effective analgesia was 388±24.88 minutes in the BN group and was higher (p-value <0.001) in comparison to the BF group, which was 304.70±15.76 minutes.

CONCLUSION

Nalbuphine was more effective than fentanyl in providing post-operative analgesia when used as an adjuvant to hyperbaric bupivacaine.

Comparison of Side Effects of Nalbuphine and Morphine in the Treatment of Pain in children with Cancer: A Prospective Study

Contemporary pain management regimens in children do not include the use of the middle step of the analgesic ladder, i.e., weak opioids. The aim of this study was to analyse the comparison of side effects and the therapeutic efficacy of morphine and nalbuphine in pain management in children with cancer. We conducted an observational, prospective study and analysed medical records of patients treated at the Clinic of Paediatric Haematology and Oncology of the University Hospital in Wroclaw (Poland), who developed mucositis during treatment. The efficacy and safety of both drugs were analysed, and the efficacy of pain relief and the incidence of adverse effects characteristic of opioid drugs were compared. The cases of 96 of children treated with opioid drugs nalbuphine or morphine were analysed. Nalbuphine therapy was accompanied by a statistically significantly lower incidence of side effects such as skin pruritus, constipation, and micturition disorders compared to morphine (p < 0.05). After the discontinuation of nalbuphine, signs of withdrawal syndrome were much less frequent than after morphine (p < 0.05). In Conclusion, nalbuphine used as a pain killer in children with oncological disorder is a safe drug. It provides stable analgesia in most children. Compared to morphine, the side effects typical of opioid use are less common, and the incidence decreases over time.

Nalbuphine as an Intrathecal Adjuvant to 0.5% Hyperbaric Bupivacaine in Two Different Doses for Postoperative Analgesia After Abdominal Hysterectomy: A Prospective, Randomized, Double-Blind Control Study

Introduction: Adding adjuvant drugs to intrathecal local anesthetics improves the quality and duration of the sensory blockade and prolongs postoperative analgesia. Intrathecal opioids are synergistic with local anesthetics, thereby intensifying the sensory block without increasing the sympathetic block. This study was designed to comparatively evaluate the two different dosages of nalbuphine as intrathecal adjuvants on subarachnoid block (SAB) characteristics of 0.5% hyperbaric bupivacaine.

Methods: A randomized, triple arm study was conducted on 60 adult female patients with American Society of Anesthesiologists physical status I and II, aged 30-60 years, scheduled for total abdominal hysterectomy under SAB. Patients were randomized into three groups: group I received 15 mg of 0.5% hyperbaric bupivacaine, group II received 15 mg of 0.5% hyperbaric bupivacaine with 1.6 mg of nalbuphine, and group III received 15 mg of 0.5% hyperbaric bupivacaine with 2.4 mg of nalbuphine. The primary outcome was the duration of analgesia, while secondary outcomes included onset, duration of sensory and motor block, maximum cephalic extension, and two dermatome segment regressions.

Results: The onset time of the sensory block was 3.2 ± 1.0 minutes, 3.5 ± 1.6 minutes, and 3.1 ± 1.1 minutes in groups I, II, and III, respectively. The onset time of the motor block was 8.5 ± 1.0 minutes, 8.5 ± 1.1 minutes, and 8.2 ± 1.1 minutes in groups I, II, and III, respectively. The onset of sensory and motor blocks was comparable among the three groups with no statistically significant difference (p > 0.05). The total duration of analgesia was 117.8 ± 23.3 minutes, 166.8 ± 27.8 minutes, and 181.8 ± 25.9 minutes in groups I, II, and III, respectively, with a statistically significant difference. Few incidences of manageable hypotension, but no incidences of bradycardia or respiratory insufficiency, occurred. Five patients of the control group shivered, which was managed well by tramadol 50 mg and ondansetron 4 mg. No patient suffered from pruritus, sedation, respiratory depression, nausea, and vomiting.

Conclusion: The study concluded that intrathecal nalbuphine in a 1.6 mg dose is an effective adjuvant to 0.5% hyperbaric bupivacaine for SAB. It potentiated the SAB characteristics and enhanced the duration of analgesia with no effect on respiration. Nalbuphine in a dose of 2.4 mg did not offer any added advantage.

Co-administration of nalbuphine attenuates the morphine-induced anxiety and dopaminergic alterations in morphine-withdrawn rats

INTRODUCTION

The classical effects of exogenous opioids, such as morphine, are predominantly mediated through μ-opioid receptors. The chronic use of morphine induces anxiety-like behavior causing functional changes in the mesolimbic dopaminergic system. The mixed μ/κ-agonist, nalbuphine, used either as an analgesic or as an adjuvant with morphine, produces different and opposite effects. However, whether nalbuphine can be used to antagonize morphine-induced anxiety and dopaminergic alterations is not fully known.

OBJECTIVE

This study aimed to compare acute and chronic effects of nalbuphine on morphine-induced anxiety and dopaminergic alterations in rats.

METHODS

Male adult Wistar albino rats were made opioid-dependent by administering increasing doses of morphine (5-25 mg/kg; i.p.; b.i.d.). Withdrawal was induced by naloxone (1 mg/kg, i.p.), 4 h after the last morphine injection. Anxiety-like behavior was measured using Activity Monitor (Coulbourn Instruments, Inc. USA). Thereafter, the animals were sacrificed and the brain dissected out and the level of cAMP and the transcriptional and translational expression of TH was measured. Nalbuphine was co-administered with morphine, acutely and chronically, at various doses (0.1, 0.3, 1.0, 3.0 mg/kg, i.p.).

RESULTS

Morphine-dependent rats showed a significant higher anxiety and cAMP levels and a significant decrease in the expression of TH. Co-administration of chronic doses of nalbuphine attenuates the higher anxiety, cAMP levels, and upregulates the TH expressions; however, the acute nalbuphine treatment does not attenuate the morphine-induced side effects.

CONCLUSION

Therefore, nalbuphine might have an important role in attenuating the anxiety and the effects of the dopaminergic pathway and may have potential in the treatment of opioid addiction.

Benzimidazole Derivative Ameliorates Opioid-Mediated Tolerance during Anticancer- Induced Neuropathic Pain in Mice

BACKGROUND

Cancer is known to be the second significant cause of death worldwide. Chemotherapeutic agents such as platinum-based compounds are frequently used single-handedly or accompanied by additional chemotherapies to treat cancer patients. Chemotherapy-induced peripheral painful neuropathy is seen in around 40% of patients who are treated with platinum-based compounds, including cisplatin. This not only decreases the quality of life of patients but also patients' compliance with cisplatin.

OBJECTIVES

Nalbuphine, an opioid, is frequently used to treat acute and chronic pain, coupled with cisplatin in cancer patients. However, long term use of nalbuphine induces tolerance to its analgesic effects. We employed the same strategy to induce tolerance in mice.

METHODS

Here, we investigated analgesic effects of 2-[(pyrrolidin-1-yl) methyl]-1H-benzimidazole (BNZ), a benzimidazole derivative, on nalbuphine-induced tolerance during cisplatin-induced neuropathic pain using hot plate test, tail-flick tests and von Frey filament in mouse models. Furthermore, we investigated the effects of BNZ on the expression of Tumor Necrosis Factor-alpha (TNF-α) in the spinal cord.

RESULTS

The results showed that BNZ reduced tolerance to analgesic effects of nalbuphine and TNF-α expression in mice.

CONCLUSION

BNZ could be a potential drug candidate for the management of nalbuphine-induced tolerance in cisplatin-induced neuropathic pain.

Intranasal solid lipid nanoparticles for management of pain: A full factorial design approach, characterization & Gamma Scintigraphy

Pain is a noxious stimulus caused due to tissue damage and varies from mild to severe. Nalbuphine (NLB) is an approved, inexpensive, non-controlled, opioid agonist/antagonist analgesic used worldwide in various clinical settings for pain management. The current study aims to formulate NLB loaded solid lipid nanoparticles (SLNs) using solvent injection technology. The morphological and chemical structure of the developed SLNs were characterized using Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM) and Fourier Transformation Infrared Spectroscopy (FTIR). The results revealed from the point prediction confirmation in design expert software was the formulation of NLB-SLNs with an average particle size of (170.07 ± 25.1 nm), encapsulation efficiency (93.6 ± 1.5%) & loading capacity of 26.67%. The in-vitro permeation of developed NLB-SLNs was observed to be 94.18% at 8 h when compared with NLB solution whose maximum permeation was seen within 3 h of application. Efficacy of the formulation was also evaluated using eddy's hot plate method, where the onset of action started within 10 min of administration, and the maximum effect was observed at 1 h. The NLB-SLNs was screened for cytotoxicity in human embryonic kidney cells (HEK-293), and the dosage was considered safe when administered intranasally in animal since no detectable effect to the brain was observed. Biodistribution and gamma scintigraphy study of NLB-SLNs showed the prepared formulation reaching the target site, i.e. brain and was retained. Conclusively, the prepared NLB-SLNs formulation was safe and effective in producing an analgesic effect in vivo.

New and emerging treatments for vaso-occlusive pain in sickle cell disease

Introduction: Acute pain from episodic vaso-occlusion (VOC) spans the lifespan of almost everyone with sickle cell disease (SCD), while additional chronic pain develops in susceptible individuals in early adolescences. Frequent acute pain with chronic pain causes significant physical and psychological morbidity, and frequent health-care utilization. Available pharmacologic therapies reduce acute pain frequency but few evidence-based therapies are available for chronic pain. Areas covered: An extensive PubMed literature search was performed with appropriate search criteria. The pathophysiology of acute pain from VOC in SCD is very complex with many events subsequent to sickle polymer formation. Sensitization of pain pathways and alterations of brain networks contributes to the experience of chronic pain. Numerous therapies targeting putative VOC mechanisms are in clinical trials, and show considerable promise. Alternative analgesic treatments for acute and chronic pain have been examined in small patient cohorts, but formal clinical trials are lacking. Expert opinion: Childhood is likely a critical window for prevention of acute and later chronic pain. New multimodal analgesic therapies are needed, particularly for chronic pain, and should be examined in clinical trials. Given the multifactorial nature of both pain and VOC, simultaneously targeting multiple mechanisms may be the optimal approach for effective preventive therapies.

Effect of different doses of intrathecal nalbuphine as adjuvant to ropivacaine in elective lower limb surgeries: A dose finding study

BACKGROUND AND AIM

Nalbuphine as an adjuvant intrathecally can produce significant analgesia with minimal side effects. However, no research has been done with isobaric ropivacaine. We, therefore, in this prospective, randomised double-blind study tried to find the optimal dose of intrathecal nalbuphine with isobaric 0.75% ropivacaine for elective lower limb surgeries.

MATERIALS AND METHODS

One hundred American Society of Anaesthesiologists I and II patients undergoing elective lower limb surgery were divided into four groups randomly: groups A, B, C and D, who received 0.5 mL normal saline or 0.4, 0.8 and 1.6 mg nalbuphine made up to 0.5 mL normal saline added to 22.5 mg (total volume 3.5 mL) isobaric 0.75% ropivacaine, respectively. The onset of sensory and motor block, two-segment regression time, duration of sensory and motor block, Visual Analogue Scale (VAS) and the incidence of adverse effects were compared between the groups.

RESULTS

The onset of both sensory and motor blockade was faster with addition of 0.4, 0.8 and 1.6 mg of nalbuphine when compared with ropivacaine alone; however, it was not statistically significant (P > 0.05). Two-segment regression time and duration of analgesia and motor blockade were highest with 1.6 mg of nalbuphine followed by 0.8, 0.4 and plain 0.75% ropivacaine (P < 0.05). The duration of sensory blockade in all four groups was slightly more than the duration of motor blockade. VAS readings were comparable in all nalbuphine groups when compared with ropivacaine group. Haemodynamic variability among the four groups was comparable. Incidence of adverse effects was highest in the 1.6-mg group when compared with others, although it was statistically insignificant (P > 0.05).

CONCLUSION

Nalbuphine can be a good alternative to other opioids as an adjuvant intrathecally to prolong postoperative analgesia with a minimal side effect profile. Addition of nalbuphine to isobaric 0.75% ropivacaine gives the added advantage of significant analgesia with early motor recovery. We infer from our study that when compared with 1.6 mg of nalbuphine, both 0.4 and 0.8 mg nalbuphine are equally good as adjuvants to isobaric 0.75% ropivacaine in elective lower limb surgeries with prolonged analgesia, a reliable block with equal efficacy but with lesser side effects.

Effect of adding nalbuphine to intrathecal bupivacaine with morphine on postoperative nausea and vomiting and pruritus after elective cesarean delivery: a randomized double blinded study

BACKGROUND

The use of intrathecal morphine may result in serious side effects in parturients undergoing cesarean delivery. Nalbuphine, is a mu receptor antagonist and a ĸappa receptor agonist. Combinations of opioid agonist and agonist antagonist can decrease the incidence of opioid related side effects. We aimed to investigate the effect of adding nalbuphine, to intrathecal morphine on postoperative nausea and vomiting and pruritus after a cesarean delivery.

METHODS

Eighty parturient undergoing elective cesarean delivery under spinal anesthesia were randomized into two similar groups. Group 1: received 10 mg of 0.5% hyperbaric bupivacaine with 0.2 mg morphine. Group 2: received as a group 1 plus 0.5 mg nalbuphine, with total volume 2.5 mL in both groups. Measurements: Data on the severity of nausea and vomiting were collected using a numerical rating scale and visual analogue scale was used to quantify pruritus. Onset and duration of sensory blockade, Visual Analog Scale for pain, the first time to ask for rescue analgesia and total rescue analgesic consumption were recorded.

RESULTS

Nausea and vomiting and pruritus severity scores and number of patients developed nausea and vomiting and pruritus were significantly lower (P<0.001) in group 2. Onset and duration of sensory block, time to first request for rescue analgesia, Visual Analog Scale for pain and paracetamol consumption showed no statistically differences between both groups (P>0.05).

CONCLUSIONS

We concluded that the addition of nalbuphine to intrathecal bupivacaine plus morphine significantly reduced the incidence and severity of postoperative nausea and vomiting and pruritus without affecting analgesic potency.

The application of nalbuphine in patient-controlled intravenous analgesia for patients undergoing subtotal gastrectomy

The aim of the present study was to investigate the analgesic effect and safety of the application of different doses of nalbuphine in patient-controlled intravenous analgesia (PCIA) for patients undergoing subtotal gastrectomy. A total of 120 patients, who underwent subtotal gastrectomy at our hospital between May, 2015 and January, 2017 under combined spinal epidural combined anesthesia, were selected. The patients received PCIA after surgery. The patients were randomly divided into four groups, including the morphine (MOP group), nalbuphine 60 mg (N60 group), nalbuphine 80 mg (N80 group) and nalbuphine 100 mg (N100 group). The first dose of PCIA treatment was 2 ml, the background dose was 2 ml/h, PCIA dose was 0.5 ml, and the lockout time was 15 min. Postoperative vital signs and adverse reactions (bleeding, fullness and aching of upper abdomen and vomiting) were recorded. The visual analogue scale (VAS) and Ramsay sedation score of patients were evaluated. The number of PCIA and analgesia-related complications during analgesia were recorded. No significant differences in general data were found among the four groups (P>0.05). The VAS score of the three nalbuphine groups was lower than that of the MOP group, but the differences were not significant. All postoperative Ramsay sedation scores of the four groups showed appropriate sedation, but no significant differences were found between the groups. Compared with the MOP group, the use of postoperative PCIA was significantly delayed and the number of PCIA was significantly smaller in the three nalbuphine groups (P<0.05). The results show that the analgesic effect and safety of the use of PCIA for patients undergoing subtotal gastrectomy were satisfactory.

Naturally occurring bioactive Cyclobutane-containing (CBC) alkaloids in fungi, fungal endophytes, and plants

This article focuses on the occurrence and biological activities of cyclobutane-containing (CBC) alkaloids obtained from fungi, fungal endophytes, and plants. Naturally occurring CBC alkaloids are of particular interest because many of these compounds display important biological activities and possess antitumour, antibacterial, antimicrobial, antifungal, and immunosuppressive properties. Therefore, these compounds are of great interest in the fields of medicine, pharmacology, medicinal chemistry, and the pharmaceutical industry. Fermentation and production of CBC alkaloids by fungi and/or fungal endophytes is also discussed. This review presents the structures and describes the activities of 98 CBC alkaloids.

Strategies for preventing side effects of systemic opioid in postoperative pediatric patients

BACKGROUND AND OBJECTIVES

Opioid is the gold standard for treating moderate-to-severe pain in pediatric patients. However, its undesirable side effects lead to unsatisfied postoperative pain management outcome (Pediatr Anesth, 17, 2007, 756). The most commonly reported opioid-related side effects are vomiting (40%), pruritus (20-60%) (Anesthesiology, 77, 1992, 162; Drugs, 67, 2007, 2323), and constipation (15-90%) (Int J Clin Pract, 61, 2007, 1181). The potential life-threatening adverse event, respiratory depression, is less common (0.0013%) (Pediatr Anesth, 20, 2010, 119). The aim of this review was to evaluate prevention strategies that have been shown to decrease opioid side effects in pediatric patients during the postoperative period.

METHODS

Literature searches were conducted from 1984 to February 2013. Meta-analysis, systematic review, and randomized, placebo-controlled studies were obtained from PubMed and the Cochrane Library. The medical subject heading (MeSH) terms were opioid analgesics, adverse effects, pediatrics, children, side effects, and postoperative pain.

RESULTS AND CONCLUSION

Data from 62 studies were reviewed. The strategies that could effectively prevent and reduce opioid side effects in pediatric patients during the postoperative period included minimizing the amount of opioid consumption by a multimodal approach, opioid titration, using local anesthetic techniques and providing the specific prophylaxis for each side effect.

Nalbuphine-induced psychosis treated with naloxone

PURPOSE

A case of nalbuphine-induced psychosis, which resolved after the administration of naloxone, is described.

SUMMARY

A 25-year-old African-American woman with a history of systemic lupus erythematosus was admitted to the hospital for management of cholecystitis. A laparoscopic cholecystectomy was performed, and the patient received multiple doses of i.v. hydromorphone for postoperative pain management. Four days later, shortly after receiving a dose of i.v. nalbuphine for opioid-induced pruritus, she experienced an acute psychotic event, with symptoms including intense headache, akathisia, altered mental status, and formication (a hallucinatory sensation of insects crawling on the skin). The neuropsychiatric symptoms abated within 5 minutes of two consecutively administered doses of i.v. naloxone. During this event, which lasted 25-30 minutes, there was no evidence of metabolic abnormalities and were no signs of infection. The patient did not have a history of mental illness or substance abuse. The patient did not receive further doses of nalbuphine and did not experience similar events during her hospital stay; she was discharged home 10 days later without further complications. According to the algorithm of Naranjo et al., the case was assigned a score of 6, indicating a probable adverse reaction to nalbuphine.

CONCLUSION

A patient developed an acute psychotic reaction that was probably secondary to administration of i.v. nalbuphine for opioid-induced pruritus. Evidence supporting this diagnosis included correlation between the timing of administration of nalbuphine and symptom onset and the marked improvement in mentation following the administration of naloxone.

Analysis of the transport of and cytotoxic effects for nalbuphine solution in corneal cells

OBJECTIVE

To assess the in vitro effects of various nalbuphine concentrations on viability and wound healing ability of corneal cells and potential drug transport through the corneal epithelium.

SAMPLE

Cultured canine and human corneal epithelial cells (CECs) and cultured canine corneal stromal fibroblasts.

PROCEDURES

CECs and stromal fibroblasts were exposed to nalbuphine (concentration of solutions ranged from 0% to 1.2%) for up to 30 minutes, and viability was assessed with a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. A standard scratch test technique was used. Wound healing of CECs and stromal fibroblasts was evaluated following treatment with nalbuphine solutions < 0.1%. Liquid chromatography-mass spectrometry-mass spectrometry analysis was used to evaluate drug transport across a monolayer and a multilayer of human CECs.

RESULTS

A progressive decrease in viability was detected in canine CECs for all nalbuphine treatment groups, whereas treatment with only 0.5% or 1.2% nalbuphine significantly reduced corneal stromal fibroblast viability, compared with results for control cells. Within 24 hours, treatment with 0.1% nalbuphine solution significantly altered the healing rate of both canine CECs and stromal fibroblasts. Continuous increases in transport rates of nalbuphine were detected with time for both the monolayer and multilayer of human CECs.

CONCLUSIONS AND CLINICAL RELEVANCE

In vitro, nalbuphine potentially could penetrate through corneal tissue, but it may cause damage to the corneal epithelium and stromal fibroblasts. Therefore, nalbuphine potentially may impair corneal wound healing.

Combination of opioid agonist and agonist-antagonist: patient-controlled analgesia requirement and adverse events among different-ratio morphine and nalbuphine admixtures for postoperative pain

BACKGROUND

Nalbuphine, a mixed agonist-antagonist opioid, has a potential to attenuate the mu-opioid effects and to enhance the kappa-opioid effects. However, when morphine and nalbuphine are mixed together, the clinical interactions in different combining ratios on analgesic effect and adverse events are unknown.

METHODS

This randomized, double-blind controlled study investigated five different combining ratios of morphine and nalbuphine in 311 patients undergoing gynaecologic operations. The concentrations [morphine (mg ml(-1))]/[nalbuphine (mg ml(-1))] were 1/0 in Group 1, 0.75/0.25 (ratio 1:3) in Group 2, 0.5/0.5 (ratio 1:1) in Group 3, 0.25/0.75 (ratio 3:1) in Group 4, and 0/1 in Group 5. Patient-controlled analgesia (PCA) requirement, postoperative pain, and adverse events were evaluated throughout the postoperative 24 h period.

RESULTS

Twenty-four hour PCA requirements were similar among the five groups. Verbal rating scores for pain were statistically higher in Groups 2 and 4 than in Group 3. The incidences of pruritus were higher in Group 1 (15.6%) than in Group 2 (6.2%), Group 3 (3.4%), Group 4 (1.6%), and Group 5 (0%). The incidences and severity of dizziness, nausea, and vomiting were not significantly different.

CONCLUSIONS

The interaction between morphine and nalbuphine in PCA admixture on analgesia is additive. Combinations of morphine and nalbuphine in PCA can decrease the incidence of pruritus, and the antipruritus effect is ratio-dependent. This may provide a novel combination strategy of opioid agonist and agonist-antagonist for postoperative pain management after gynaecologic surgery.