The Analgesic Effect of Gabapentin as a Prophylactic Anticonvulsant Drug on Postcraniotomy Pain: A Prospective Randomized Study

Temporal Muscle Swelling after Clipping Surgery with Frontotemporal Craniotomy Is Associated with Immediate Postcraniotomy Headache

Immediate postcraniotomy headache frequently occurs within the first 48 h after surgery. The mechanisms underlying immediate postcraniotomy headache are not yet fully understood, and effective treatments are not yet established. This study aimed to identify the factors associated with immediate postcraniotomy headache in patients who underwent clipping surgery with frontotemporal craniotomy and to examine the effects of these factors on postcraniotomy headache. A total of 51 patients were included in this study. Immediate postcraniotomy headache was defined as pain with numerical rating scale score ≥4 on postoperative day 7. Sixteen patients (31.4%) had immediate postcraniotomy headache. The headache-positive group had a higher incidence of preoperative analgesic use (50.0% vs. 5.7%, respectively, p < 0.001), increased temporal muscle swelling ratio (137.0%±30.2% vs. 112.5%±30.5%, respectively, p = 0.01), and higher postoperative analgesic use (12.9±5.8 vs. 6.7±5.2, respectively, p < 0.001) than the headache-negative group. The risk factors independently associated with immediate postcraniotomy headache were preoperative analgesic use and temporal muscle swelling by >115.15% compared with the contralateral side in the receiver operating characteristic analysis. Postcraniotomy headache was significantly more common in patients with preoperative analgesic use and temporal muscle swelling than in those without (p < 0.001 and p = 0.002, respectively). Altogether, patients with immediate postcraniotomy headache had greater preoperative analgesic use, greater temporal muscle swelling ratio, and higher postoperative analgesic use than those without. Thus, temporal muscle swelling is a key response to immediate postcraniotomy headache.

Gabapentin as part of a multimodal pain protocol for selective dorsal rhizotomy does not impact percentage of rootlets transected

PURPOSE

We aim to determine whether preoperatively initiated gabapentin for pain control impacts the percentage of rootlets cut during monitored, limited laminectomy selective dorsal rhizotomy (SDR) procedure.

METHODS

This retrospective cohort study includes participants with cerebral palsy who had SDR for treatment of spasticity between 2010 and 2019 at a single-institution tertiary care center. One-level laminectomy SDR aimed to evaluate the cauda equina roots from levels L2-S1 with EMG monitoring. Gabapentin titration began 3 weeks prior to SDR. Data was analyzed using simple linear regression. Thirty-one individuals met inclusion criteria. Mean age was 7 years, 4 months. Eighteen participants (58%) identified as male, 12 (39%) female, and one (3%) non-binary. Thirty (97%) had bilateral CP. Sixteen (52%) were GMFCS II, four (13%) GMFCS III, five (16%) GMFCS IV, and six (19%) GMFCS V.

RESULTS

Mean percentage of rootlets transected was 50.75% (SD 6.00, range 36.36-60.87). There was no relationship between the dose of gabapentin at time of SDR and percentage of rootlets cut with a linear regression slope of - 0.090 and an R2 of 0.012 (P = 0.56).

CONCLUSION

Results indicate that preoperative initiation of gabapentin did not impact the percentage of rootlets transected. Thus, gabapentin can be initiated prior to SDR at moderate dosages without impacting SDR surgical outcomes.

Headache Management in Individuals with Brain Tumor

Headache occurs commonly in individuals diagnosed with cerebral neoplasm. Though the features of a brain tumor-associated headache may vary, a progressive nature of headache and a change in headache phenotype from a prior primary headache disorder often are identified. Pathophysiologic mechanisms proposed for headache associated with brain tumor include headache related to traction on pain-sensitive structures, activation of central and peripheral pain processes, and complications from surgical, chemotherapeutic and/or radiotherapy treatment(s). Optimization of headache management is important for an individual's quality of life. Treatments are based upon patient-specific goals of care and may include tumor-targeted medical and surgical interventions, as well as a multimodal headache treatment approach incorporating acute and preventive medications, nutraceuticals, neuromodulation devices, behavioral interventions, anesthetic nerve blocks, and lifestyles changes.

Modulation of nociception and pain-evoked neurobehavioral responses by levetiracetam in a craniotomy pain model

Traditional and novel analgesic modalities have been extensively tested for post-craniotomy pain management, yet the role of newer antiepileptic drugs in this area remains obscure. This study investigates the impact of levetiracetam (LEV) on pain modulation and neurobehavioral performance in a craniotomy model. Fifty-six Wistar rats were randomly assigned into seven groups: no intervention (CTRL), administration of placebo or LEV with no further intervention (PBO and LEV, respectively), and sham-operation or craniotomy in placebo (PBO-SHAM and PBO-CR, respectively) or LEV-treated rats (LEV-SHAM and LEV-CR, respectively). Pain was assessed by the rat grimace scale before, and at 8 and 24 h after craniotomy, following intraperitoneal injections of LEV (100 mg/kg twice daily) or normal saline two consecutive days before and on the craniotomy day. Elevated plus-maze and olfactory social memory tests were performed at 24- and 48 h post-craniotomy, respectively. Upon testing conclusion blood samples were collected for cytokines estimation. Levetiracetam administration enhanced antinociception in sham and craniotomy groups. In the elevated plus-maze test, LEV-CR rats spent more time in investigating open arms and performed more open arm entries than PBO-SHAM and PBO-CR animals. The olfactory test revealed no between-groups difference in acquisition time during first contact with a juvenile rat, while LEV-CR rats spent less time to recognize the same juvenile rat compared to PBO-SHAM and PBO-CR groups. Furthermore, LEV-treatment attenuated cortisol, interleukin-6 and TNF-a release, in sham and craniotomy animals. In conclusion, preemptive use of LEV decreases nociception, improves pain-evoked behavior and attenuates stress response in rats subjected to craniotomy.

Options to manage postcraniotomy acute pain in neurosurgery: no protocol available

The physical processes of incision, traction and hemostasis used for craniotomy, stimulate nerve fibers and specific nociceptors, resulting in postoperative pain. During the first 24 h after craniotomy, 87% of patients have postoperatory pain. The rate of suffering pain after craniotomy falls 3% for every year of life. The objective of this study is to review the available therapeutic options to help physicians treating this pain, and discuss pain mechanisms, pathophysiology, plasticity, risk factors and psychological factors. This is a narrative review of the literature from 1970 to June 2019. Data were collected by doing a search in PubMed, EMBASE, Cochrane Reviews and a manual search of all relevant literature references. The literature includes some drugs treatment: Opioids, codeine, morphine, and tramadol, anti-inflammatory non-steroids such as cyclooxygenase-2 inhibitors, gabapentin. It discusses: side effects, pharmacodynamics and indications of each drug, anatomy and Inervation of Skull and its Linigs, pathogenesis of pain Post-craniotomy, scalp nerve block, surgical nerve injury, neuronal plasticity, surgical factors and chronic post-surgical pain.

Neuroanesthesiology Update

This review is intended to provide a summary of the literature pertaining to the perioperative care of neurosurgical patients and patients with neurological diseases. General topics addressed in this review include general neurosurgical considerations, stroke, neurological monitoring, and perioperative disorders of cognitive function.

Narrative review of acute post-craniotomy pain. Concept and strategies for prevention and treatment of pain

The aim of this narrative review is to confirm that acute pain after craniotomy is frequent and presents with moderate to severe intensity. We also highlight the importance of not only treating post-craniotomy pain, but also of preventing it in order to reduce the incidence of chronic pain. Physicians should be aware that conventional postoperative analgesics (non-steroidal anti-inflammatory, paracetamol, cyclooxygenase inhibitors 2, opioids) are not the only options available. Performing a scalp block prior to surgical incision or after surgery, the use of intraoperative dexmedetomidine, and the perioperative administration of pregabalin are just some alternatives that are gaining ground. The management of post-craniotomy pain should be based on perioperative multimodal analgesia in the framework of an "enhaced recovery after surgery" (ERAS) approach.

Pharmacological interventions for the prevention of acute postoperative pain in adults following brain surgery

BACKGROUND

Pain following brain surgery can compromise recovery. Several pharmacological interventions have been used to prevent pain after craniotomy; however, there is currently a lack of evidence regarding which interventions are most effective.

OBJECTIVES

The objectives are to assess the effectiveness of pharmacological interventions for prevention of acute postoperative pain in adults undergoing brain surgery; compare them in terms of additional analgesic requirements, incidence of chronic headache, sedative effects, length of hospital stay and adverse events; and determine whether these characteristics are different for certain subgroups.

SEARCH METHODS

We searched MEDLINE, Embase, CINAHL, CENTRAL, Web of Science and two trial registries together with reference checking and citation searching on 28th of November 2018.

SELECTION CRITERIA

We included blinded and non-blinded, randomized controlled trials evaluating pharmacological interventions for the prevention of acute postoperative pain in adults undergoing neurosurgery, which had at least one validated pain score outcome measure.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. We calculated mean differences for the primary outcome of pain intensity; any pain scores reported on a 0 to 100 scale were converted to a 0 to 10 scale.

MAIN RESULTS

We included 42 completed studies (3548 participants) and identified one ongoing study. Nonsteroidal anti-inflammatories (NSAIDs) Nonsteroidal anti-inflammatories (NSAIDs) reduce pain up to 24 hours (0 to 6 hours, MD -1.16, 95% CI -1.57 to -0.76; 12 hours, MD -0.62, 95% CI -1.11 to -0.14; 24 hours, MD -0.66, 95% CI -1.18 to -0.13; 6 studies, 742 participants; all high-quality evidence). Results for other outcomes were imprecise (additional analgesic requirements: MD 1.29 mg, 95% CI -5.0 to 2.46, 4 studies, 265 participants; nausea and vomiting RR 1.34, 95% CI 0.30 to 5.94, 2 studies, 345 participants; both low-quality evidence). Dexmedetomidine reduces pain up to 12 hours (0 to 6 hours, MD -0.89, 95% CI -1.27 to -0.51, moderate-quality evidence; 12 hours, MD -0.81, 95% CI -1.21 to -0.42, low-quality evidence). It did not show efficacy at 24 hours (MD -0.08, 95% CI -0.32 to 0.16; 2 studies, 128 participants; low-quality evidence). Dexmedetomidine may decrease additional analgesic requirements (MD -21.36 mg, 95% CI -34.63 to -8.1 mg, 2 studies, 128 participants, low-quality evidence). Results for other outcomes were imprecise (nausea and vomiting RR -0.43, 95% CI 0.06 to 3.08, 3 studies, 261 participants; hypotension RR 0.5, 95% CI 0.05 to 5.28, 3 studies, 184 participants; both low-quality evidence). Scalp blocks may reduce pain up to 48 hours (0 to 6 hours, MD -0.98, 95% CI -1.66 to -0.3, 10 studies, 414 participants; 12 hours, MD -0.95, 95% CI -1.53 to -0.37, 8 studies, 294 participants; 24 hours, MD -0.78, 95% CI -1.52 to -0.05, 9 studies, 433 participants, all low-quality evidence; 48 hours, MD -1.34, 95% CI -2.57 to -0.11, 4 studies, 135 participants, very low-quality evidence. When studies with high risk of bias were excluded, significance remained at 12 hours only. Scalp blocks may decrease additional analgesia requirements (SMD -1.11, 95% CI -1.97 to -0.25, 7 studies, 314 participants). Results for other outcomes were imprecise (nausea and vomiting RR 0.66, 95% CI 0.33 to 1.32, 4 studies, 165 participants, very low-quality evidence). Scalp Infiltration may reduce pain postoperatively but efficacy was inconsistent, with a significant effect at 12 and 48 hours only (12 hours, MD -0.71, 95% CI -1.34 to -0.08, 7 studies, 309 participants, low-quality evidence; 48 hours, MD - 1.09, 95% CI -2.13 to - 0.06, 3 studies, 128 participants, moderate-quality evidence). No benefit was observed at other times (0 to 6 hours, MD -0.64, 95% CI -1.28 to -0.00, 9 studies, 475 participants, moderate-quality evidence; 24 hours, MD -0.39, 95% CI -1.06 to 0.27,6 studies, 260 participants, low-quality evidence. Scalp infiltration may reduce additional analgesia requirements MD -9.56 mg, 95% CI -15.64 to -3.49, 6 studies, 345 participants, very low-quality evidence). When studies with high risk of bias were excluded, scalp infiltration lost the pain benefit at 12 hours and effects on additional analgesia requirements, but retained the pain-reducing benefit at 48 hours (MD -0.56, 95% CI -1.20 to -0.32, 2 studies, 100 participants, very low-quality evidence). Results for other outcomes were imprecise (nausea and vomiting, RR 0.74, 95% CI 0.48 to 1.41, 4 studies, 318 participants, low-quality evidence). Pregabalin or gabapentin may reduce pain up to 6 hours (2 studies, 202 participants), MD -1.15,95% CI -1.66 to -0.6, 2 studies, 202 participants, low-quality evidence). One study examined analgesic efficacy at 12 hours showing significant benefit. No analgesia efficacy was shown at later times (24 hours, MD -0.29, 95% CI -0.78 to -0.19; 48 hours, MD - 0.06, 95% CI -0.86 to 0.77, 2 studies, 202 participants, low-quality evidence). Additional analgesia requirements were not significantly less (MD -0.37 (95% CI -1.10 to 0.35, 3 studies, 234 participants, low-quality evidence). Risk of nausea and vomiting was significantly reduced (RR 0.51, 95% CI 0.29 to 0.89, 3 studies, 273 participants, low-quality evidence). Results for other outcomes were imprecise (additional analgesia requirements: MD -0.37, 95% CI -1.10 to 0.35, 3 studies, 234 participants, low-quality evidence). Acetaminophen did not show analgesic benefit (0 to 6 hours, MD -0.35, 95% CI -1.00 to 0.30; 12 hours, MD -0.51, 95% CI -1.04 to 0.03, 3 studies, 332 participants, moderate-quality evidence; 24 hours, MD -0.34, 95% CI -1.20 to 0.52, 4 studies, 439 participants, high-quality evidence). Results for other outcomes remained imprecise (additional analgesia requirements, MD 0.07, 95% CI -0.86 to 0.99, 4 studies, 459 participants, high-quality evidence; length of hospitalizations, MD -3.71, 95% CI -14.12 to 6.7, 2 studies, 335 participants, moderate-quality evidence).

AUTHORS' CONCLUSIONS

There is high-quality evidence that NSAIDs reduce pain up to 24 hours postoperatively. The evidence for reductions in pain with dexmedetomidine, pregabalin or gabapentin, scalp blocks, and scalp infiltration is less certain and of very low to moderate quality. There is low-quality evidence that scalp blocks and dexmedetomidine may reduce additional analgesics requirements. There is low-quality evidence that gabapentin or pregabalin may decrease nausea and vomiting, with the caveat that the total number of events for this comparison was low.

Postoperative Craniotomy Pain in Emergent versus Non-emergent Cases

BACKGROUND

Postoperative pain control in craniotomies poses multiple challenges. Pain must be addressed, but the use of medications must be weighed against risks. Craniotomies risk neurologic injury and so postoperative examinations are critical. Medications used to address pain can alter the neurological examination or cause bleeding leading to misdiagnosis of complications.

OBJECTIVE

Determine if there is a significant difference in postoperative pain from emergent craniotomies vs. non-emergent craniotomies Methods: A retrospective review included 102 cases performed from 2010-2016; pain scores were compared on post-operative days one, two, and three between emergent and non-emergent craniotomies.

RESULTS

Pain scores for emergent cases on post-operative days one through three were 5.1 (standard deviation (SD)=2.9), 5.9 (SD=2.1), 4.7 (SD=3.0) respectively. Pain scores for non-emergent cases on post-operative days one through three were 5.7 (SD=2.6), 4.8 (SD=2.8), and 4.6 (SD=3.0) respectively. A one-way analysis of variance (ANOVA) was conducted to compare pain scores between groups for each post-operative day. On post-operative day, one there was no significant difference between the groups [F(1,100)=0.49, p=0.485]. On post-operative day two, there was no significant difference between the groups [F(1,100)=2.17, p=0.143]. On post-operative day three, there was no significant difference between the groups [F(1,98)=0.002, p=0.957].

CONCLUSION

There is no significant difference in the level of pain on postoperative days one through three between emergent and non-emergent craniotomy patients.

Pre-emptive scalp infiltration with dexamethasone plus ropivacaine for postoperative pain after craniotomy: a protocol for a prospective, randomized controlled trial

Background: Approximately 55–87% of the patients undergoing craniotomy experience moderate to severe pain during the first 48 hrs after surgery, which negatively influences patients’ postoperative rehabilitation. Recently, local infiltration of analgesia (LIA) has been widely performed clinically as a promising analgesic method that could avoid the side effects of analgesics but only has a short pain-free duration; researchers have clarified that the addition of dexamethasone to LIA could provide significant analgesic effects and significantly prolong the duration of analgesic effects without obvious complications for various types of surgeries. To date, no studies have evaluated the addition of dexamethasone to LIA for patients receiving craniotomy. The aim of the study was to test the hypothesis that pre-emptive scalp infiltration with a steroid (dexamethasone) plus a local anesthetic (ropivacaine) could achieve superior postoperative analgesic effects to a local anesthetic (ropivacaine) alone in adult patients undergoing a craniotomy.

Study design and methods: This study is a randomized controlled trial that will include one intervention and one control group involving a total of 140 adults scheduled for elective craniotomy for resection of supratentorial tumors under general anesthesia and with an anticipated full recovery within 2 hrs postoperatively. The intervention will involve pre-emptive scalp infiltration with ropivacaine plus dexamethasone (the dexamethasone group) or ropivacaine alone (the control group), and the participants in both groups will complete a 6-month follow-up. The primary outcome will be the cumulative sufentanil consumption within 48 hrs postoperatively.

Discussion: The intervention, if effective, this study will provide clinically important information on the role of dexamethasone in scalp infiltration for post-craniotomy pain management.

Scheduled Intravenous Acetaminophen Improves Patient Satisfaction With Postcraniotomy Pain Management: A Prospective, Randomized, Placebo-controlled, Double-blind Study

BACKGROUND

Postcraniotomy pain can be difficult to manage with opioids due to opioid-related side effects, including drowsiness, nausea/vomiting, confusion, and pupillary changes, potentially masking the signs of postoperative neurological deterioration. Intravenous (IV) acetaminophen, a nonopioid analgesic, has been reported to have opioid-sparing effects after abdominal and orthopedic surgeries. This study investigates whether IV acetaminophen has similar effects after craniotomy.

MATERIALS AND METHODS

In this prospective, randomized, placebo-controlled, double-blind clinical trial, 100 adult patients scheduled to undergo supratentorial craniotomy for excision of a brain mass were randomized to receive either IV acetaminophen or placebo preincision and then every 6 hours for a total of 24 hours after surgery. Total 24-hour opioid consumption, pain scores, satisfaction with overall pain management, time to meet postanesthesia care unit discharge criteria, and incidence of opioid-related side effects were compared.

RESULTS

There was no difference in the 24-hour postoperative opioid consumption in morphine equivalents between the IV acetaminophen group (median, 11 mg; n=45) and the placebo group (median, 10.1 mg; n=41). No statistically significant difference of visual analog scale pain score was observed between 2 treatment groups. Patient satisfaction with overall postoperative pain management was significantly higher in the IV acetaminophen group than the placebo group on a 1 to 10 scale (8.1±0.4 vs. 6.9±0.4; P=0.03). There was no significant difference in secondary outcomes, including the incidence of opioid-related side effects.

CONCLUSIONS

IV acetaminophen, as adjunctive therapy for craniotomy procedures, did not show an opioid-sparing effect in patients for the 24 hours after craniotomy; however, it was associated with improved patient satisfaction regarding overall pain control.

Designing a pain management protocol for craniotomy: A narrative review and consideration of promising practices

BACKGROUND

Craniotomy is a relatively common surgical procedure with a high incidence of postoperative pain. Development of standardized pain management and enhanced recovery after surgery (ERAS) protocols are necessary and crucial to optimize outcomes and patient satisfaction and reduce health care costs.

METHODS

This work is based upon a literature search of published manuscripts (between 1996 and 2017) from Pubmed, Cochrane Central Register, and Google Scholar. It seeks to both synthesize and review our current scientific understanding of postcraniotomy pain and its part in neurosurgical ERAS protocols.

RESULTS

Strategies to ameliorate craniotomy pain demand interventions during all phases of patient care: preoperative, intraoperative, and postoperative interventions. Pain management should begin in the perioperative period with risk assessment, patient education, and premedication. In the intraoperative period, modifications in anesthesia technique, choice of opioids, acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs), regional techniques, dexmedetomidine, ketamine, lidocaine, corticosteroids, and interdisciplinary communication are all strategies to consider and possibly deploy. Opioids remain the mainstay for pain relief, but patient-controlled analgesia, NSAIDs, standardization of pain management, bio/behavioral interventions, modification of head dressings as well as patient-centric management are useful opportunities that potentially improve patient care.

CONCLUSIONS

Future research on mechanisms, predictors, treatments, and pain management pathways will help define the combinations of interventions that optimize pain outcomes.

A systematic review of perioperative seizure prophylaxis during brain tumor resection: the case for a multicenter randomized clinical trial

OBJECTIVE

The majority of neurosurgeons administer antiepileptic drugs (AEDs) prophylactically for supratentorial tumor resection without clear evidence to support this practice. The putative benefit of perioperative seizure prophylaxis must be weighed against the risks of adverse effects and drug interactions in patients without a history of seizures. Consequently, the authors conducted a systematic review of prospective randomized controlled trials (RCTs) that have evaluated the efficacy of perioperative seizure prophylaxis among patients without a history of seizures.

METHODS

Five databases (PubMed/MEDLINE, Cochrane Central Register of Controlled Trials, CINAHL/Academic Search Complete, Web of Science, and ScienceDirect) were searched for RCTs published before May 2017 and investigating perioperative seizure prophylaxis in brain tumor resection. Of the 496 unique research articles identified, 4 were selected for inclusion in this review.

RESULTS

This systematic review revealed a weighted average seizure rate of 10.65% for the control groups. There was no significant difference in seizure rates among the groups that received seizure prophylaxis and those that did not. Further, this expected incidence of new-onset postoperative seizures would require a total of 1258 patients to enroll in a RCT, as determined by a Farrington-Manning noninferiority test performed at the 0.05 level using a noninferiority difference of 5%.

CONCLUSIONS

According to a systematic review of major RCTs, the administration of prophylactic AEDs after brain tumor resection shows no significant reduction in the incidence of seizures compared with that in controls. A large multicenter randomized clinical trial would be required to assess whether perioperative seizure prophylaxis provides benefit for patients undergoing brain tumor resection.

Perioperative pregabalin for reducing pain, analgesic consumption, and anxiety and enhancing sleep quality in elective neurosurgical patients: a prospective, randomized, double-blind, and controlled clinical study

OBJECTIVE

The aim of this study was to assess in-hospital (immediate) postoperative pain scores and analgesic consumption (primary goals) and preoperative anxiety and sleep quality (secondary goals) in patients who underwent craniotomy and were treated with pregabalin (PGL). Whenever possible, out-of-hospital pain scores and analgesics usage data were obtained as well.

METHODS

This prospective, randomized, double-blind and controlled study was conducted in consenting patients who underwent elective craniotomy for brain tumor resection at Tel Aviv Medical Center between 2012 and 2014. Patients received either 150 mg PGL (n = 50) or 500 mg starch (placebo; n = 50) on the evening before surgery, 1.5 hours before surgery, and twice daily for 72 hours following surgery. All patients spent the night before surgery in the hospital, and no other premedication was administered. Opioids and nonsteroidal antiinflammatory drugs were used for pain, which was self-rated by means of a numerical rating scale (score range 0–10).

RESULTS

Eighty-eight patients completed the study. Data on the American Society of Anesthesiologists class, age, body weight, duration of surgery, and intraoperative drugs were similar for both groups. The pain scores during postoperative Days 0 to 2 were significantly lower in the PGL group than in the placebo group (p < 0.01). Analgesic consumption was also lower in the PGL group, both immediately and 1 month after surgery. There were fewer requests for antiemetics in the PGL group, and the rate of postoperative nausea and vomiting was lower. The preoperative anxiety level and the quality of sleep were significantly better in the PGL group (p < 0.01). There were no PGL-associated major adverse events.

CONCLUSIONS

Perioperative use of twice-daily 150 mg pregabalin attenuates preoperative anxiety, improves sleep quality, and reduces postoperative pain scores and analgesic usage without increasing the rate of adverse effects.

Clinical trial registration no.: NCT01612832 (clinicaltrials.gov)

The New Antiepileptic Drugs: Their Neuropharmacology and Clinical Indications

The administration of antiepileptic drugs (AEDs) is the first treatment of epilepsy, one of the most common neurological diseases. Therapeutic guidelines include newer AEDs as front-line drugs; monotherapy with new AEDs is delivered in Japan. While about 70% of patients obtain good seizure control by taking one to three AEDs, about 60% experience adverse effects and 33% have to change drugs. Compared to traditional AEDs, the prolonged administration of new AEDs elicits fewer adverse effects and fewer drug interactions and their teratogenicity may be lower. These characteristics increase drug compliance and allow combination therapy for drug-resistant epilepsy, although the antiepileptic effects of the new AEDs are not greater than of traditional AEDs. Comorbidities are not rare in epileptics; many adult patients present with stroke and brain tumors. In stroke patients requiring risk control and in chemotherapy-treated brain tumor patients, their fewer drug interactions render the new AEDs advantageous. Also, new AEDs offer favorable side benefits for concurrent diseases and conditions. Patients with stroke and traumatic brain injury often present with psychiatric/behavioral symptoms and cognitive impairment and some new AEDs alleviate such symptoms. This review presents an outline of the new AEDs used to treat adult patients based on the pharmacological activity of the drugs and discusses possible clinical indications from the perspective of underlying causative diseases and comorbidities.

Options for perioperative pain management in neurosurgery

Moderate-to-severe pain following neurosurgery is common but often does not get attention and is therefore underdiagnosed and undertreated. Compounding this problem is the traditional belief that neurosurgical pain is inconsequential and even dangerous to treat. Concerns about problematic effects associated with opioid analgesics such as nausea, vomiting, oversedation, and increased intracranial pressure secondary to elevated carbon dioxide tension from respiratory depression have often led to suboptimal postoperative analgesic strategies in caring for neurosurgical patients. Neurosurgical patients may have difficulty or be incapable of communicating their need for analgesics due to neurologic deficits, which poses an additional challenge. Postoperative pain control should be a priority, because pain adversely affects recovery and patient outcomes. Inconsistent practices and the quality of current analgesic strategies for neurosurgical patients still leave room for improvement. Given the complexity of postoperative pain management for these patients, multimodal strategies are often required to optimize pain control and at the same time limit undesired side effects.

Gabapentin induces edema, hyperesthesia and scaling in a depressed patient; a diagnostic challenge

Gabapentin is a common drug used as analgesic and anticonvulsant and also is prescribed for insomnia, depression, obsessive – compulsive disorder and panic attack. We report a case of a 48-year-old man who is prescribed gabapentin because of insomnia, headache, and depressed mood. In the first period of using the drug no complication has been seen. However in the next period, side-effects such as hyperesthesia, scaling and severe localized edema has been observed. After several laboratory tests and imaging, no reason was found for his edema. And after discontinuing gabapentin the pain and edema was quite relieved. We found out the brand of the drug has been switched in the second stage. The point which makes our study special is the incidence of side-effects such as severe edema, scaling and hyperesthesia for the first time because of using gabapentin and changing the drug combination.

Integrative review: postcraniotomy pain in the brain tumour patient

AIM

To conduct an integrative review to examine evidence of pain and associated symptoms in adult (≥21 years of age), postcraniotomy, brain tumour patients hospitalized on intensive care units.

BACKGROUND

Healthcare providers believe craniotomies are less painful than other surgical procedures. Understanding how postcraniotomy pain unfolds over time will help inform patient care and aid in future research and policy development.

DESIGN

Systematic literature search to identify relevant literature. Information abstracted using the Theory of Unpleasant Symptoms' concepts of influencing factors, symptom clusters and patient performance. Inclusion criteria were indexed, peer-reviewed, full-length, English-language articles. Keywords were 'traumatic brain injury', 'pain, post-operative', 'brain injuries', 'postoperative pain', 'craniotomy', 'decompressive craniectomy' and 'trephining'.

DATA SOURCES

Medline, OVID, PubMed and CINAHL databases from 2000-2014.

REVIEW METHOD

Cooper's five-stage integrative review method was used to assess and synthesize literature.

RESULTS

The search yielded 115 manuscripts, with 26 meeting inclusion criteria. Most studies were randomized, controlled trials conducted outside of the United States. All tested pharmacological pain interventions. Postcraniotomy brain tumour pain was well-documented and associated with nausea, vomiting and changes in blood pressure, and it impacted the patient's length of hospital stay, but there was no consensus for how best to treat such pain.

CONCLUSION

The Theory of Unpleasant Symptoms provided structure to the search. Postcraniotomy pain is experienced by patients, but associated symptoms and impact on patient performance remain poorly understood. Further research is needed to improve understanding and management of postcraniotomy pain in this population.

Esmolol reduces anesthetic requirements thereby facilitating early extubation; a prospective controlled study in patients undergoing intracranial surgery

BACKGROUND

Adequate cerebral perfusion pressure with quick and smooth emergence from anesthesia is a major concern of the neuroanesthesiologist. Anesthesia techniques that minimize anesthetic requirements and their effects may be beneficial. Esmolol, a short acting hyperselective β-adrenergic blocker is effective in blunting adrenergic response to several perioperative stimuli and so it might interfere in the effect of the anesthetic drugs on the brain. This study was designed to investigate the effect of esmolol on the consumption of propofol and sevoflurane in patients undergoing craniotomy.

METHOD

Forty-two patients that underwent craniotomy for aneurysm clipping or tumour dissection were randomly divided in two groups (four subgroups). Anesthesia was induced with propofol, fentanyl and a single dose of cis-atracurium, followed by continuous infusion of remifentanil and either propofol or sevoflurane. Patients in the esmolol group received 500 mcg/kg of esmolol bolus 10 min before induction of anesthesia, followed by additional 200 mcg/kg/min of esmolol. Monitoring of the depth of anesthesia was also performed using the Bispectral Index-BIS and cardiac output. The inspired concentration of sevoflurane and the infusion rate of propofol were adjusted in order to maintain a BIS value between 40-50. Intraoperative emergence was detected by the elevation of BIS value, HR or MAP.

RESULTS

The initial and the intraoperative doses of propofol and sevoflurane were 18-50 mcg/kg/min and 0.2-0.5 MAC respectively in the esmolol group, whereas in the control group they where 100-150 mcg/kg/ and 0.9-2.0 MAC respectively (p = 0.000 for both groups). All procedures were anesthesiologically uneventful with no episodes of intraoperative emerge.

CONCLUSIONS

Esmolol is effective not only in attenuating intraoperative hemodynamic changes related to sympathetic overdrive but also in minimizing significant propofol and sevoflurane requirements without compromising the hemodynamic status. ClinicalTrials.gov Identifier: NCT02455440 . Registered 26 May 2015.

Enhanced recovery after surgery for oncological craniotomies

Enhanced recovery after surgery (ERAS) initiatives in the fields of gastrointestinal and pelvic surgery have contributed to improved postoperative functional status for patients and decreased length of stay. A similar comprehensive protocol is lacking for patients undergoing craniotomy for tumor resection. A literature search was performed using PubMed. These references were reviewed with a preference for recent high quality studies. Cohort and retrospective studies were also included if higher levels of evidence were lacking. A literature search was conducted for scalp blocks and minimally invasive craniotomies. Papers were scored using Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria for evidence level and recommendation grade. Seventeen ERAS items were reviewed and recommendations made. The current body of evidence is insufficient to create a standardized protocol for craniotomy and tumor resection. However, this initial review of the literature supports pursuing future research initiatives that explore modalities to improve functional recovery and decrease length of stay in craniotomy patients.

Pain following craniotomy: reassessment of the available options

Pain following craniotomy has frequently been neglected because of the notion that postcraniotomy patients do not experience severe pain. However a gradual change in this outlook is observed because of increased sensitivity of neuroanaesthesiologists and neurosurgeons toward acute postcraniotomy pain. Multiple modalities exist for treating this variety of pain each with its own share of advantages and disadvantages. However, individually none of these modalities has been proclaimed as the best and applicable universally. A considerable amount of dispute remains to ascertain the appropriate therapeutic regimen for treating postcraniotomy pain in spite of numerous trials using different drugs and their combinations. This review aims to highlight the genesis, characteristics, and different strategies that are undertaken for management of acute postcraniotomy pain. Chronic postcraniotomy pain which can be debilitating sequelae is also discussed concisely.

Effects of Anesthetic Management on Early Postoperative Recovery, Hemodynamics and Pain After Supratentorial Craniotomy

Various clinical trials have assessed how intraoperative anesthetics can affect early recovery, hemodynamics and nociception after supratentorial craniotomy. Whether or not the difference in recovery pattern differs in a meaningful way with anesthetic choice is controversial. This review examines and compares different anesthetics with respect to wake-up time, hemodynamics, respiration, cognitive recovery, pain, nausea and vomiting, and shivering. When comparing inhalational anesthetics to intravenous anesthetics, either regimen produces similar recovery results. Newer shorter acting agents accelerate the process of emergence and extubation. A balanced inhalational/intravenous anesthetic could be desirable for patients with normal intracranial pressure, while total intravenous anesthesia could be beneficial for patients with elevated intracranial pressure. Comparison of inhalational anesthetics shows all appropriate for rapid emergence, decreasing time to extubation, and cognitive recovery. Comparison of opioids demonstrates similar awakening and extubation time if the infusion of longer acting opioids was ended at the appropriate time. Administration of local anesthetics into the skin, and addition of corticosteroids, NSAIDs, COX-2 inhibitors, and PCA therapy postoperatively provided superior analgesia. It is also important to emphasize the possibility of long-term effects of anesthetics on cognitive function. More research is warranted to develop best practices strategies for the future that are evidence-based.

The effect of gabapentin on reducing pain after laparoscopic gastric bypass surgery in patients with morbid obesity: a randomized clinical trial

Background:

Pain after laparoscopic gastric bypass surgery (LGBP) is a major problem. Gabapentin is an anticonvulsant drug that can be effective in postoperative pain control.

Objectives:

This study examined the effect of preoperative administration of gabapentin on reducing pain after LGBP in patients with morbid obesity.

Patients and Methods:

This randomized clinical trial was performed in Hazrat Rasoul Akram Medical Center in Tehran. A total of 60 patients undergoing LGBP were randomly allocated into two groups; one group received 100 mg of oral gabapentin and the other group received placebo. Pain was evaluated at recovery time, and at the first, second, fourth and sixth hour of surgery by visual analog scale. The number and dose of opioid use after surgery and incidence of postoperative complications, such as nausea and vomiting, agitation, and headache, were also recorded.

Results:

The mean pain score in the group receiving gabapentin was significantly lower than the placebo group (P < 0.001). Indications and dose of opioid consumption between the two groups were not statistically significant. Incidence of nausea/vomiting (P = 0.028) as well as agitation (P = 0.037) was significantly lower in the gabapentin group.

Conclusions:

Administration of gabapentin before surgery can reduce pain after LGBP. Furthermore, it is not accompanied by significant short-term adverse effects.

Gabapentin significantly decreases posthemorrhoidectomy pain: a prospective study

PURPOSE

Surgery for hemorrhoidectomy remains a painful procedure despite advances in pain management. Gabapentin is widely used for control of acute and chronic pain. Our aim was to evaluate the effect of gabapentin on posthemorrhoidectomy pain and opioid use.

METHODS

A prospective, open-label study. Patients requiring hemorrhoid surgery were recruited to be in control (standard of care) or treatment group (standard of care plus daily gabapentin).

RESULTS

Twenty-one treatment and 18 control patients were recruited. One patient from study group and two patients from control group were excluded due to failure to follow up. Pain levels for gabapentin group were significantly lower on postoperative days 1, 7, and 14 compared to the standard treatment group (3.68 vs. 6.82 p < 0.01, 2.68 vs. 5 p = 0.02 and 0.75 vs. 3.64 p < 0.001 respectively). There was a trend toward less opioids taken in gabapentin group for postoperative days 1, 7, and 14 (4.69 vs. 6.36; 2.13 vs. 2.73, and 0.125 vs. 0.9) but it did not reach statistical significance. The average hemorrhoidal grade and number of hemorrhoidal complexes removed was slightly higher in gabapentin group. Five control group patients experienced postoperative complications versus two gabapentin group patients. No gabapentin related complications were seen in the treatment group. The average cost of gabapentin course was $5.34 per patient.

CONCLUSIONS

Daily use of gabapentin in perioperative period significantly decreased reported levels of postoperative pain. This effective, inexpensive addition improves pain after hemorrhoid surgery. Randomized placebo-controlled studies would better define the usefulness of this medication for posthemorrhoidectomy pain.

[Antiepileptic prophylaxis for elective neurosurgery]

In tumoral surgery, the risk factors for perioperative epilepsy can be roughly grouped into two categories: those related to the preoperative patient's conditions (type and location of the tumors, their impact on the surrounding brain…) and those specifically related to surgery (cerebral edema, parenchymal hematoma, surgical approach, complete or incomplete resection...). The first category is supposed to be responsible for preoperative and late postoperative epilepsy, while the second would be more related to the risk of epilepsy in the first postoperative week (or may be even in the first 48hours). It is well accepted (but not always respected) by the neuro-oncologists that there is no indication for preventive antiepileptic drugs (AED) in a patient with a brain tumor that has never presented seizure. However, every seizure crisis must be treated medically. Neurosurgical procedure (which is also a key factor for controlling epilepsy when it occurs. The AED should then be maintained as appropriate. In the absence of preoperative treatment, it has never been shown that prophylactic AED significantly decreases the incidence of postoperative seizures, early or late. Yet, the opposite has not been shown neither, and many groups use AED despite the risk of side effects and an uncertain risk-benefit ratio. Currently, postoperative epilepsy is much less frequent than it was 20 or 30years ago, and the risk of AED side effects also decreases with the latest generation of molecules (such as levetiracetam). So, AED risks and benefits tend to diminish in parallel, but their relationship is still to be assessed. In practice, a modern attitude would restrict prophylactic AED use to the higher risk patients (preoperative epilepsy, temporal astrocytoma, the extent of edema and mass effect...). A drug of last generation should be used, starting one week before surgery. The duration of the treatment should be limited to one week postoperatively in the absence of seizure.

Perioperative pain management in the neurosurgical patient

Perioperative pain management in neurosurgical patients has been inadequately recognized and treated. An increased awareness of pain management and advances in understanding of pain modulation and pathophysiology have led to improved perioperative care of patients. There is a need to assess neurologic function while providing superior analgesia with minimal side effects. Several classes of drugs are currently available or under investigation for use as adjuvants or alternative therapies. There remains a need to determine the best treatment of perioperative pain in this patient population. Improved awareness, assessment, and treatment of pain result in better care and overall patient outcome.

Effect of intravenous parecoxib on post-craniotomy pain

BACKGROUND

Pain management in craniotomy patients is challenging, with mild-to-moderate pain intensity, moderate-to-high risk of postoperative nausea and vomiting (PONV), and potentially catastrophic consequences of analgesic-related side-effects. The aim of this study was to determine whether i.v. parecoxib administered at dural closure during craniotomy decreased total morphine consumption and morphine-related side-effects compared with placebo.

METHODS

One hundred adult patients presenting for supratentorial craniotomy under propofol/remifentanil anaesthesia were randomized to receive parecoxib, 40 mg i.v., or placebo in a double-blind manner. All patients received local anaesthetic scalp infiltration, regular i.v. paracetamol, nurse-administered morphine in the post-anaesthesia care unit (PACU) until verbal analogue pain scores were ≤4/10 and patient-controlled morphine thereafter. Morphine consumption, pain intensity, and analgesia-related side-effects were recorded during the first 24 h after operation.

RESULTS

Ninety-six patients (49 control and 47 parecoxib) were included in the analyses. Fifty-nine (61%) patients received morphine in the PACU and only one patient (control) did not receive any morphine in the postoperative period. There were no significant differences between the two groups in morphine consumption [20 (range: 0-102) vs 16 (range: 1-92) mg; P=0.38], pain intensity [excellent/very good pain relief in 78% of parecoxib patients; 74% of control patients (P=0.72)] or analgesia-related side-effects (PONV in 51% of parecoxib patients; 56% of control patients; P=0.55) in the first 24 h after operation. No major morbidity was recorded.

CONCLUSIONS

Our study demonstrated no clinical benefit to adding i.v. parecoxib to local anaesthetic scalp infiltration, i.v. paracetamol, and patient-controlled i.v. morphine after supratentorial craniotomy.

Adjuvant analgesics in cancer pain: a review

Adjuvant analgesics (co-analgesics) are medications whose primary indication is the management of a medical condition with secondary effects of analgesia. Cancer pain is multifactorial and often involves inflammatory, nociceptive, and neuropathic pain subtypes. Adjuvant analgesics used in conjunction with opioids have been found to be beneficial in the management of many cancer pain syndromes; however, they are currently underutilized. Antidepressants, anticonvulsants, local anesthetics, topical agents, steroids, bisphosphonates, and calcitonin are all adjuvants which have been shown to be effective in the management of cancer pain syndromes. When utilizing analgesic adjuvants in the treatment of cancer pain, providers must take into account the particular side effect profile of the medication. Ideally, adjuvant analgesics will be initiated at lower dosages and escalated as tolerated until efficacy or adverse effects are encountered.

Preoperative gabapentin for acute post-thoracotomy analgesia: a randomized, double-blinded, active placebo-controlled study

BACKGROUND

The role of preoperative gabapentin in postoperative pain management is not clear, particularly in patients receiving regional blockade. Patients undergoing thoracotomy benefit from epidural analgesia but still may experience significant postoperative pain. We examined the effect of preoperative gabapentin in thoracotomy patients.

METHODS

Adults undergoing elective thoracotomy were enrolled in this prospective, randomized, double-blinded, placebo-controlled study, and randomly assigned to receive 600 mg gabapentin or active placebo (12.5 mg diphenhydramine) orally within 2 hours preoperatively. Standardized management included thoracic epidural infusion, intravenous patient-controlled opioid analgesia, acetaminophen and ketorolac. Pain scores, opioid use and side effects were recorded for 48 hours. Pain was also assessed at 3 months.

RESULTS

One hundred twenty patients (63 placebo and 57 gabapentin) were studied. Pain scores did not significantly differ at any time point (P = 0.53). Parenteral and oral opioid consumption was not significantly different between groups on postoperative day 1 or 2 (P > 0.05 in both cases). The frequency of side effects such as nausea and vomiting or respiratory depression was not significantly different between groups, but gabapentin was associated with decreased frequency of pruritus requiring nalbuphine (14% gabapentin vs. 43% control group, P < 0.001). The frequency of patients experiencing pain at 3 months post-thoracotomy was also comparable between groups (70% gabapentin vs. 66% placebo group, P = 0.72).

CONCLUSIONS

A single preoperative oral dose of gabapentin (600 mg) did not reduce pain scores or opioid consumption following elective thoracotomy, and did not confer any analgesic benefit in the setting of effective multimodal analgesia that included thoracic epidural infusion.

Acute and chronic pain following craniotomy

PURPOSE OF REVIEW

The purpose of the review is to describe what is currently known about the mechanisms, incidence and risk factors for acute and chronic postcraniotomy pain. The review will also summarize the evidence supporting the prevention and management of acute and chronic postcraniotomy pain.

RECENT FINDINGS

Current studies suggest acute and chronic pain is common in patients after craniotomy. Surgical and patient factors may influence the incidence and severity of pain and a multimodal approach to acute postcraniotomy pain is recommended. Although codeine and tramadol are frequently used in the postoperative period, research suggests morphine provides superior efficacy with a good safety profile. Local anesthesia with nerve blocks has not been shown to consistently reduce acute postoperative pain, though it has recently been demonstrated to dramatically reduce the incidence of chronic pain. Despite this, little is known about the mechanisms, prevention and treatment of chronic postcraniotomy pain.

SUMMARY

Acute and chronic pain following craniotomy is frequent and underrecognized. Several surgical and patient risk factors predispose patients to pain following neurosurgery. Further research is needed to determine the mechanisms, predictors, prevention and optimal treatment of acute and chronic pain following craniotomy.