Use of Intrathecal Neostigmine as an Adjunct to Other Spinal Medications in Perioperative and Peripartum Analgesia: A Meta-analysis

A Comparison of Intrathecal Dexmedetomidine and Neostigmine as Adjuvant to Ropivacaine for Lower Limb Surgeries: A Double-blind Randomized Controlled Study

Objective:

The primary objective of this study was to compare the analgesic effects of intrathecal ropivacaine with or without neostigmine or dexmedetomidine in lower limb surgeries. Secondary objectives were to study the characteristics of block, duration of analgesia, postoperative analgesic requirement, and associated side effects.

Materials and Methods:

Seventy-five patients posted for elective orthopedic lower limb surgeries under spinal anesthesia were randomly divided into three equal groups to receive intrathecal ropivacaine 0.5% alone (Group R), with adjuvant 5 μg dexmedetomidine (Group R + D) or 50 μg neostigmine (Group R + N). Time to achieve T10 sensory block, time to 2-segment regression, duration of regression to L4, maximum modified Bromage score and duration of analgesia were noted. The incidences of adverse events such as nausea, vomiting, hypotension, bradycardia, desaturation, shivering, and itching were also noted. Statistical analysis was performed using two sample t-test for normally distributed variables and Pearson's Chi-squared test for categorical data. The level of significance was set as P < 0.05.

Results:

Quality of motor and sensory blockage was significantly better in both Group R + D and Group R + N than Group R. Mean time to achieve T10 sensory block was lowest, time taken in regression of block by 2-segments and duration of regression to L4 was longest in Group R + D and was significant when compared to other groups. Adverse effects such as nausea and vomiting were highest in Group R + N and was statistically significant as compared to other groups.

Conclusions:

Dexmedetomidine is a better intrathecal adjuvant emerged as compared to neostigmine due to faster onset of anesthesia, better intra- and post-operative analgesia and prolonged duration of motor and sensory blockade without significant increase in adverse effects.

Intrathecal buprenorphine versus fentanyl as adjuvant to 0.75% ropivacaine in lower limb surgeries

BACKGROUND AND AIMS

This study aims to compare the anesthesia characteristics between buprenorphine and fentanyl when added as an adjuvant to intrathecal ropivaciane in an attempt to prolong the duration of spinal anesthesia.

MATERIAL AND METHODS

The present prospective double-blind study was undertaken on ninety American Society of Anesthesiologist I and II patients between 18 and 60 years of age undergoing subarachnoid block for lower limb surgery. Group I (n = 30) patients were administered 3 ml of intrathecal solution (2.8 ml of 0.75% ropivacaine + 0.2 ml of isotonic sodium chloride), while Groups II and III patients (n = 30 each) received 2.8 ml 0.75% ropivacaine + 0.2 ml buprenorphine (60 μg) and 2.8 ml 0.75% ropivacaine + 0.2 ml fentanyl (10 μg), respectively. Following parameters were observed: Onset times and duration of sensory and motor block, time to first analgesic use, total dose of rescue analgesia, intra- and post-operative pain scores based on visual analog scale, sedation scores, hemodynamic parameters, and side effects if any. Data were analyzed by appropriate statistical tests and P < 0.05 were considered significant.

RESULTS

Time to onset of sensory and motor block in all the three groups was comparable. However, duration of sensory block was significantly prolonged in Groups II and III in comparison to Group I (P < 0.05) and it was the longest in Group II (P < 0.05). The duration of motor blockade was similar in all the three groups. The time to first analgesic dose was also significantly prolonged in Groups II and III as compared to Group I (P < 0.05) but was comparable between Groups II and III. Intra- and post-operative hemodynamic parameters, as well as side effects, were comparable.

CONCLUSION

Addition of buprenorphine and fentanyl as adjuvants to intrathecal 0.75% ropivacaine prolongs postoperative pain relief without causing any increase in the duration of motor blockade but buprenorphine is better as compared to fentanyl in prolonging the duration of sensory block and achieving a better outcome in terms of pain relief.

A comparison between intrathecal clonidine and neostigmine as an adjuvant to bupivacaine in the subarachnoid block for elective abdominal hysterectomy operations: A prospective, double-blind and randomized controlled study

BACKGROUND AND AIMS

Adjuvant to the local anesthetic agent has proven benefits when used intrathecally. With regards to intrathecal bupivacaine as control, we have compared in this study the effects of clonidine and neostigmine when co-administered intrathecally with hyperbaric (0.5%) bupivacaine for abdominal hysterectomy.

MATERIALS AND METHODS

This prospective, randomized, double-blind study was conducted from May 2009 to June 2011. A total of 150 patients of American Society of Anaesthesiology grades I and II scheduled for abdominal hysterectomy under spinal anesthesia were randomly allocated into three groups. A volume of 3 ml of 0.5% hyperbaric bupivacaine was respectively added 1 ml solution containing 5% dextrose and 75 mcg of neostigmine in Group N, 1 ml containing 5% dextrose and 30 mcg of clonidine in Group C and 1 ml of 5% dextrose in Group D (control). We compared the sensory and motor block, the surgical condition, the duration of spinal analgesia and the side-effect profile.

RESULTS AND OBSERVATIONS

Sensory and motor blocks and duration of spinal analgesia were significantly increased in both Group C and Group N compared to Group D. More incidences of Nausea and vomiting were observed in Group N compared to other groups. The surgical condition was poorer in Group N compared to Group C.

CONCLUSION

Both intrathecal clonidine and neostigmine increase the bupivacaine-induced spinal block. However, clonidine provides better surgical condition and fewer incidences of nausea and vomiting.

Comparison of the effects of sugammadex and neostigmine on postoperative nausea and vomiting

BACKGROUND AND OBJECTIVES

The aim of our study is to compare the effects of sugammadex and neostigmine, used for neuromuscular blockage antagonism, on postoperative nausea and vomiting (PONV).

METHODS

Our study was completed with 98 ASA I-II risk patients undergoing endotracheal intubation under general anesthesia. At the end of the surgery patients were randomly divided into two groups given 2mgkg^-1 sugammadex (Group S) or 50μgkg^-1 neostigmine plus 0.2mgkg^-1 atropine (Group N). Monitoring and recording times were set as 1 hour postoperative and from 1-6, 6-12, and 12-24hours. The anti-emetic amounts administered were recorded.

RESULTS

In the first hour postoperative 13 patients in Group N (27%) and 4 in Group S (8%) were observed to have nausea and/or vomiting and the difference was statistically significant (p=0.0016). During the 24 hours of monitoring there was no significant difference in the incidence and severity of PONV (p>0.05), however the number of patients given ondansetron for PONV treatment in Group N was statistically significantly higher than the number in Group S (16 in Group N, 6 in Group S, p<0.011).

CONCLUSIONS

At the end of our study comparing neostigmine with sugammadex for neuromuscular blockage antagonism, we found use of sugammadex had lower incidence of PONV in the postoperative 1st hour and less anti-emetic use in 24 hours of monitoring.

NMDA Receptor Antagonists, Gabapentinoids, α-2 Agonists, and Dexamethasone and Other Non-Opioid Adjuvants: Do They Have a Role in Plastic Surgery?

BACKGROUND

Inadequate pain control and opioid-related adverse effects result in delayed patient recovery and discharge times. Adjuvants help to improve the quality of analgesia and decrease opioid consumption, consequently decreasing opioid-related effects, such as nausea and vomiting, sedation, ileus, and respiratory depression. We review the mechanisms and clinical evidence for nonopioid adjuvants.

METHODS

MEDLINE, EMBASE, and the Cochrane Register were searched for meta-analyses, systematic reviews, and randomized, controlled trials that compared the adjuvants ketamine, gabapentin, pregabalin, dexmedetomidine, clonidine, and dexamethasone with placebo. Keywords used in the search included "plastic surgery," "reconstructive surgery," "opioid," "pain," "analgesia," and the names of each adjuvant. The references of included studies were searched for additional relevant studies.

RESULTS

Ketamine was found in 6 meta-analyses to have a significant reduction in opioid requirements and may reduce the hyperalgesia associated with opioids. This seems to be most beneficial in surgeries where high postoperative pain is expected. Multiple robust trials have demonstrated that the gabapentinoids and α-2 agonists significantly improve quality of analgesia and decrease opioid consumption. Two recent meta-analyses found that a single low-dose of dexamethasone used for postoperative nausea and vomiting prophylaxis may also improve postoperative analgesia. There is also emerging evidence for the use of low-dose naloxone, adenosine, and neuraxial neostigmine and acupuncture as part of a successful multimodal pain management regimen.

CONCLUSIONS

Although there is a lack of studies specifically focused in the plastic and reconstructive surgery patient population, the existing literature provides information about when the above adjuvants are likely to have the greatest impact.

The evolution of spinal/epidural neostigmine in clinical application: Thoughts after two decades

Since the first clinical application of analgesia following spinal anticholinesterase by 1940's, several clinical double-blind studies have been conducted to date, where intrathecal doses of neostigmine in humans ranged from 750 to 1 μg, due to side-effects. Conversely, epidural neostigmine has been evaluated in proportionally higher doses and represents an alternative, but still deserves more investigation concerning both acute and chronic pain, as it seems devoid of important side-effects.

Effect of different doses of dexmedetomidine as adjuvant in bupivacaine -induced subarachnoid block for traumatized lower limb orthopaedic surgery: a prospective, double-blinded and randomized controlled study

BACKGROUND AND AIMS

Improved pain management for blunt trauma to the lower extremity has shown to reduce morbidity, induce early ambulation and improve long-term outcomes. Dexmedetomidine; a selective α-2 agonist; has recently been used intrathecally in different doses to prolong spinal anaesthesia. We evaluated the effect of adding two different doses of dexmedetomidine to hyperbaric bupivacaine for spinal anaesthesia. The primary endpoints were the onset and duration of sensory, motor block and duration of analgesia.

MATERIALS AND METHODS

Eighty patients, (20-60yrs) posted for elective lower limb orthopedic surgery of traumatic origin under spinal anaesthesia were divided into 2 equal groups (Group D5&D10) in a randomized, double-blind fashion. In this prospective parallel group study, group D5(n=40) 3ml 0.5% hyperbaric bupivacaine+5μg dexmedetomidine in 0.5 ml of normal saline and group D10 (n=40) 3ml 0.5% bupivacaine+10μg dexmedetomidine in 0.5 ml of normal saline were administered intrathecally. Sensory and motor block onset times and block durations, time to first analgesic use, total analgesic need, postoperative VAS, hemodynamics and side effects were recorded for each patient.

RESULTS

Though with similar demographic profile in both groups, sensory and motor block in group D10(p<0.05) was earlier than group D5. Sensory, motor block duration and time to first analgesic use were significantly longer and the need for rescue analgesics was lower in group D10(p<0.05) than D5. 24 h VAS score was significantly lower in group D10(p<0.05). Intergroup hemodynamics was comparable (p>0.05) without any appreciable side effects.

CONCLUSION

Spinal dexmedetomidine increases the sensory, motor block duration and time to first analgesic use, and decreases analgesic consumption in a dose-dependent manner.

Consensus guidelines for the management of postoperative nausea and vomiting

The present guidelines are the most recent data on postoperative nausea and vomiting (PONV) and an update on the 2 previous sets of guidelines published in 2003 and 2007. These guidelines were compiled by a multidisciplinary international panel of individuals with interest and expertise in PONV under the auspices of the Society for Ambulatory Anesthesia. The panel members critically and systematically evaluated the current medical literature on PONV to provide an evidence-based reference tool for the management of adults and children who are undergoing surgery and are at increased risk for PONV. These guidelines identify patients at risk for PONV in adults and children; recommend approaches for reducing baseline risks for PONV; identify the most effective antiemetic single therapy and combination therapy regimens for PONV prophylaxis, including nonpharmacologic approaches; recommend strategies for treatment of PONV when it occurs; provide an algorithm for the management of individuals at increased risk for PONV as well as steps to ensure PONV prevention and treatment are implemented in the clinical setting.

Pathology of emesis: its autonomic basis

Vagal and non-vagal pathways as well as several brainstem nuclei participate in vomiting in response to different emetic stimuli. Autonomic pathways involved in nausea are less well understood. Numerous gastrointestinal disorders with prominent nausea and vomiting including gastroparesis, cyclic vomiting syndrome, and motion sickness have associated autonomic nervous system dysfunction. Autonomic disturbances are also seen with non-gastrointestinal diseases with gut manifestations such as migraine headaches, orthostatic intolerance, and familial dysautonomia. Stimulation of emetic pathways involves activation of a range of receptor subtypes. Agents acting on these receptors form the basis for antiemetic therapies. Chemotherapy-induced nausea and vomiting, a prevalent and severe consequence of anticancer treatment, is preventable in many instances by agents acting on the autonomic nervous system. Likewise, non-medication therapies may act in part via modulation of some of these same autonomic pathways.

Muscarinic pain pharmacology: realizing the promise of novel analgesics by overcoming old challenges

The antinociceptive and analgesic effects of muscarinic receptor ligands in human and nonhuman species have been evident for more than half a century. In this review, we describe the current understanding of the roles of different muscarinic subtypes in pain modulation and their mechanism of action along the pain signaling pathway, including peripheral nociception, spinal cord pain processing, and supraspinal analgesia. Extensive preclinical and clinical validation of these mechanisms points to the development of selective muscarinic agonists as one of the most exciting and promising avenues toward novel pain medications.

Intrathecal neostigmine with bupivacaine for infants undergoing lower abdominal and urogenital procedures: dose response

BACKGROUND

Intrathecal (IT) neostigmine produces dose-dependent analgesia in adults. However, the dose of spinal neostigmine has not been investigated in infants. The purpose of this study was to assess spinal anesthesia (SA) duration provided by four doses of spinal neostigmine added to bupivacaine for lower abdominal and urogenital procedures in infants.

METHODS

Seventy-five infants were randomized into five groups. The control group B received IT plain 0.5% hyperbaric bupivacaine. Groups BN.25, BN.50, BN.75, and BN1.0 received bupivacaine with 0.25, 0.5, 0.75, and 1 microg/kg of neostigmine, respectively. The primary variable was the duration of anesthesia assessed by recovery of hip flexion. Postoperative pain with facial expression, leg activity, arm activity, crying and consolability scale score, and rescue analgesic requirements were the secondary variables measured, and the side effects were noted.

RESULTS

Seventy-three infants completed the study. There was a significant linear increase in SA duration with IT neostigmine to 65.2 (4.3) min with 0.5 microg/kg (P<0.01), 88.2 (5.1) with 0.75 microg/kg (P<0.001) and 92 (4.3) with 1 microg/kg (P<0.001) from 52.4 (4.3) min with bupivacaine alone. SA duration showed no significant difference between plain bupivacaine and BN.25 (P=0.100) or between groups BN.75 and BN1.0 (P=0.451). Groups BN.75 and BN1.0 had significantly reduced pain scores, and the median duration before the first dose rescue analgesic was requested prolonged significantly (P<0.001) compared with the other three groups.

CONCLUSIONS

IT neostigmine at a dose of 0.75 microg/kg added to bupivacaine significantly prolonged SA duration with reduced postoperative pain scores and rescue analgesic requirements in infants undergoing lower abdominal and urogenital procedures. No additional benefits were provided on increasing it to 1 microg/kg.

Useful adjuvants for postoperative pain management

Adjuvants are compounds which by themselves have undesirable side-effects or low potency but in combination with opioids allow a reduction of narcotic dosing for postoperative pain control. Adjuvants are needed for postoperative pain management due to side-effects of opioid analgesics, which hinder recovery, especially in the increasingly utilized ambulatory surgical procedures. NMDA antagonists have psychomimetic side-effects at high doses, but at moderate doses do not cause stereotypic behavior but allow reduction in opioid dose to obtain better pain control. Alpha-2 adrenergic agonists cause sedation, hypotension and bradycardia at moderate doses, but at low doses can be opioid sparing especially in spinal administration. Gabapentin-like compounds have low potency against acute pain, but in combination with opioids allow a reduction in opioid dose with improved analgesia. Corticosteroids may have only a limited role as adjuvants while acetylcholine esterase inhibitors may have too many side-effects. Newer adjuvants will be needed to reduce opioid dose and concomitant side-effects, even more as same day surgeries become more routine.

The Role of the Anesthesiologist in Fast-Track Surgery: From Multimodal Analgesia to Perioperative Medical Care

BACKGROUND

Improving perioperative efficiency and throughput has become increasingly important in the modern practice of anesthesiology. Fast-track surgery represents a multidisciplinary approach to improving perioperative efficiency by facilitating recovery after both minor (i.e., outpatient) and major (inpatient) surgery procedures. In this article we focus on the expanding role of the anesthesiologist in fast-track surgery.

METHODS

A multidisciplinary group of clinical investigators met at McGill University in the Fall of 2005 to discuss current anesthetic and surgical practices directed at improving the postoperative recovery process. A subgroup of the attendees at this conference was assigned the task of reviewing the peer-reviewed literature on this topic as it related to the role of the anesthesiologist as a perioperative physician.

RESULTS

Anesthesiologists as perioperative physicians play a key role in fast-track surgery through their choice of preoperative medication, anesthetics and techniques, use of prophylactic drugs to minimize side effects (e.g., pain, nausea and vomiting, dizziness), as well as the administration of adjunctive drugs to maintain major organ system function during and after surgery.

CONCLUSION

The decisions of the anesthesiologist as a key perioperative physician are of critical importance to the surgical care team in developing a successful fast-track surgery program.

Use of neostigmine in the management of acute postoperative pain and labour pain: a review

Neostigmine is a parasympathomimetic agent that has been recently investigated for use as an adjunct analgesic agent in the perioperative and peripartum period. A number of studies have investigated the intrathecal, epidural, caudal and intra-articular routes of administration of this agent, as well as the addition of neostigmine to local anaesthetics used for brachial plexus block and intravenous regional anaesthesia. While the intrathecal administration of neostigmine produced useful analgesic effects in the postoperative period in some studies, the high incidence of adverse events, mainly nausea and vomiting, limit the clinical usefulness of this route of administration. Several studies investigated the postoperative analgesic effects of epidural neostigmine using a number of different regimens. Overall, this route of administration appeared to improve postoperative analgesia in most studies without increasing the incidence of adverse events, and merits further research. Neuraxial administration of neostigmine appears to be safe in the obstetric population, with no reported adverse effects in the mother or fetus. While intrathecal administration is limited by a high incidence of nausea and vomiting in this patient population, the epidural route appears more promising and requires further investigation. The addition of neostigmine to caudal local anaesthetics was associated with improved postoperative analgesia in a number of studies. A dose of 2 microg/kg proved to be effective in several studies but was associated with an increased incidence of vomiting in some studies. Intra-articular administration of neostigmine 500microg produced a useful analgesic effect in the postoperative period in several studies and was not associated with an increase in the incidence of adverse effects. Studies investigating the efficacy of adding neostigmine to the local anaesthetics used for brachial plexus block and intravenous regional anaesthesia reported conflicting results. Further studies are required to determine the place of the administration of neostigmine by these routes.