Acute and chronic pain following craniotomy

In situ brain tumor detection using a Raman spectroscopy system-results of a multicenter study

Safe and effective brain tumor surgery aims to remove tumor tissue, not non-tumoral brain. This is a challenge since tumor cells are often not visually distinguishable from peritumoral brain during surgery. To address this, we conducted a multicenter study testing whether the Sentry System could distinguish the three most common types of brain tumors from brain tissue in a label-free manner. The Sentry System is a new real time, in situ brain tumor detection device that merges Raman spectroscopy with machine learning tissue classifiers. Nine hundred and seventy-six in situ spectroscopy measurements and colocalized tissue specimens were acquired from 67 patients undergoing surgery for glioblastoma, brain metastases, or meningioma to assess tumor classification. The device achieved diagnostic accuracies of 91% for glioblastoma, 97% for brain metastases, and 96% for meningiomas. These data show that the Sentry System discriminated tumor containing tissue from non-tumoral brain in real time and prior to resection.

Headache in Brain Tumors

The prevalence of brain tumors in patients with headache is very low; however, 48% to 71% of patients with brain tumors experience headache. The clinical presentation of headache in brain tumors varies according to age; intracranial pressure; tumor location, type, and progression; headache history; and treatment. Brain tumor-associated headaches can be caused by local and distant traction on pain-sensitive cranial structures, mass effect caused by the enlarging tumor and cerebral edema, infarction, hemorrhage, hydrocephalus, and tumor secretion. This article reviews the current findings related to epidemiologic details, clinical manifestations, mechanisms, diagnostic approaches, and management of headache in association with brain tumors.

Nerve Blocks for Craniotomy

PURPOSE OF REVIEW

Postcraniotomy headache (PCH) is a common adverse event and can lead to various complications and decreased quality of life.

RECENT FINDINGS

To reduce postcraniotomy pain and associated complications, a multimodal pain therapy including analgesics, analgesic adjuncts, and regional anesthesia is essential. The use of opioids should be minimized to facilitate prompt postoperative neurosurgical assessment. Here, we provide an update on the latest evidence regarding the role of scalp nerve blocks in the pain management of patients undergoing craniotomy procedure. Nerve blocks are effective in alleviating postoperative pain after craniotomy. Scalp blocks contribute to lower pain levels and less opioid consumption in the first 48 h following surgery. Moreover, there is a significant decrease in patients suffering from PONV among patients who receive scalp block.

Effects of intraoperative low-dose esketamine on postoperative pain after vestibular schwannoma resection: A prospective randomized, double-blind, placebo-controlled study

AIMS

Esketamine may reduce acute postoperative pain in several settings. However, the effects of low-dose esketamine on postoperative pain after vestibular schwannoma (VS) resection with propofol/remifentanil total intravenous anaesthesia (TIVA) are unclear. The aim of this study is to observe the effects of intraoperative low-dose esketamine on postoperative pain after vestibular schwannoma resection.

METHODS

This single-centre, randomized, placebo-controlled, double-blind trial included 90 adults undergoing VS resection via the retrosigmoid approach with TIVA. The patients were randomly allocated to two groups: esketamine or control (n = 45 in each group). Patients received low-dose esketamine (0.2 mg/kg) or a similar volume of normal saline after dural closure. The primary outcome was the pain score during movement (gentle head movement) at 24 h postoperatively. Secondary outcomes included recovery time, bispectral index (BIS) values and haemodynamic profiles during the first 30 min after esketamine administration, and adverse effects.

RESULTS

Low-dose esketamine did not reduce pain scores at rest (P > .05) or with movement (P > .05) within the first 24 h after surgery. Esketamine moderately increased BIS values for at least 30 min after administration (P < .0001) but did not affect heart rate (P = .992) or mean arterial blood pressure (P = .994). Esketamine prolonged extubation time (P = .042, 95% confidence interval: 0.08 to 4.42) and decreased the effect-site concentration of remifentanil at extubation (P = .001, 95% confidence interval: -0.53 to -0.15) but did not affect the time to resumption of spatial orientation. Postoperative nausea and vomiting rates did not differ between groups, and no hallucinations or excessive sedation was observed.

CONCLUSION

Intraoperative low-dose esketamine did not significantly reduce acute pain after VS resection with propofol/remifentanil TIVA. However, BIS values increased for at least 30 min after esketamine administration.

Enhanced Recovery After Surgery for Craniotomies: A Systematic Review and Meta-analysis

The efficacy of the enhanced recovery after surgery (ERAS) protocols in neurosurgery has not yet been established. We performed a systematic review and meta-analysis of randomized controlled trials to compare the effects of ERAS protocols and conventional perioperative care on postoperative outcomes in patients undergoing craniotomy. The primary outcome was postoperative length of hospital stay. Secondary outcomes included postoperative pain visual analog pain scores, incidence of postoperative nausea and vomiting (PONV), postoperative complications, all-cause reoperation, readmission after discharge, and mortality. A literature search up to August 10, 2023, was conducted using PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus databases. Five studies, including 871 patients, were identified for inclusion in this review. Compared with conventional perioperative care, ERAS protocols reduced the length of postoperative hospital stay (difference of medians, -1.52 days; 95% CI: -2.55 to -0.49); there was high heterogeneity across studies (I2, 74%). ERAS protocols were also associated with a lower risk of PONV (relative risk, 0.79; 95% CI: 0.69-0.90; I2, 99%) and postoperative pain with a visual analog scale score ≥4 at postoperative day 1 (relative risk, 0.37; 95% CI: 0.28-0.49; I2, 14%). Other outcomes, including postoperative complications, did not differ between ERAS and conventional care groups. ERAS protocols may be superior to conventional perioperative care in craniotomy patients in terms of lower length of hospital stay, lower incidence of PONV, and improved postoperative pain scores. Further randomized trials are required to identify the impact of ERAS protocols on the quality of recovery after craniotomy.

Regional Anesthesia Techniques in Modern Neuroanesthesia Practice: A Narrative Review of the Clinical Evidence

Neurosurgical procedures are often associated with significant postoperative pain that is both underrecognized and undertreated. Given the potentially undesirable side effects associated with general anesthesia and with various pharmacological analgesic regimens, regional anesthetic techniques have gained in popularity as alternatives for providing both anesthesia and analgesia for the neurosurgical patient. The aim of this narrative review is to present an overview of the regional techniques that have been incorporated and continue to be incorporated into modern neuroanesthesia practice, presenting in a comprehensive way the evidence, where available, in support of such practice for the neurosurgical patient.

Dexmedetomidine Prevents Chronic Incisional Pain After Brain Tumor Resection: A Secondary Analysis of the Randomized Control Trial

BACKGROUND

Dexmedetomidine was reported to reduce postoperative acute pain after neurosurgery. However, the efficacy of dexmedetomidine for preventing chronic incisional pain is uncertain.

METHODS

This article is a secondary analysis of a randomized, double-blind, placebo-controlled trial. Eligible patients were randomly allocated to either the dexmedetomidine group or the placebo group. Patients assigned to the dexmedetomidine group were given a 0.6 μg kg -1 dexmedetomidine bolus followed by a 0.4 μg kg -1 h -1 maintenance dose until dural closure; placebo patients were given comparable amounts of normal saline. The primary end point was the incidence of incisional pain at 3 months after craniotomy evaluated by numerical rating scale scores and defined as any score >0. The secondary end points were postoperative acute pain scores, sleep quality, and Short-Form McGill Pain Questionnaire (SF-MPQ-2) at 3 months after craniotomy.

RESULTS

From January 2021 to December 2021, a total of 252 patients were included in the final analysis: the dexmedetomidine group (n = 128) and the placebo group (n = 124). The incidence of chronic incisional pain was 23.4% (30 of 128) in the dexmedetomidine group versus 42.7% (53 of 124) in the placebo group (risk ratio, 0.55; 95% confidence interval, 0.38-0.80; P = .001). The overall severity of chronic incisional pain was mild in both groups. Patients in the dexmedetomidine group had lower acute pain severity on movement than those in the placebo group for the first 3 days after surgery (all adjusted P < .01). Sleep quality did not differ between groups. However, the SF-MPQ-2 total sensory ( P = .01) and neuropathic pain descriptor ( P = .023) scores in the dexmedetomidine group were lower than those in the placebo group.

CONCLUSIONS

Prophylactic intraoperative dexmedetomidine infusion reduces the incidence of chronic incisional pain as well as acute pain score after elective brain tumor resections.

Effects of Scalp Nerve Block on the Quality of Recovery after Minicraniotomy for Clipping of Unruptured Intracranial Aneurysms : A Randomized Controlled Trial

OBJECTIVE

This study compared the quality of recovery (QoR) after minicraniotomy for clipping of unruptured intracranial aneurysms (UIAs) between patients with and without scalp nerve block (SNB).

METHODS

Patients were randomly assigned to the SNB (SNB using ropivacaine with epinephrine, n=27) and control (SNB using normal saline, n=25) groups. SNB was performed at the end of surgery. To assess postoperative QoR, the QoR-40, a patient-reported questionnaire, was used. The QoR-40 scores were measured preoperatively, 1-3 days postoperatively, at hospital discharge, and 1 month postoperatively. Pain and intravenous patient-controlled analgesia (IV-PCA) consumption were evaluated 3, 6, 9, and 12 hours and 1-3 days postoperatively.

RESULTS

All QoR-40 scores, including those measured 1 day postoperatively (primary outcome measure; 155.0 [141.0-176.0] vs. 161.0 [140.5-179.5], p=0.464), did not significantly differ between the SNB and control groups. The SNB group had significantly less severe pain 3 (numeric rating scale [NRS]; 3.0 [2.0-4.0] vs. 5.0 [3.5-5.5], p=0.029), 9 (NRS; 3.0 [2.0-4.0] vs. 4.0 [3.0-5.0], p=0.048), and 12 (NRS; 3.0 [2.0-4.0] vs. 4.0 [3.0-5.0], p=0.035) hours postoperatively. The total amount of IV-PCA consumed was significantly less 3 hours postoperatively in the SNB group (2.0 [1.0-4.0] vs. 4.0 [2.0-5.0] mL, p=0.044).

CONCLUSION

After minicraniotomy for clipping of UIAs, SNB reduced pain and IV-PCA consumption in the early postoperative period but did not improve the QoR-40 scores.

Incidence, predictors, and impact of acute post-operative pain after cranial neurosurgery: A prospective cohort study

Objectives

Pain is common after craniotomy. Its incidence and predictors in developing nations are not adequately studied. We aimed to assess the incidence, predictors, and impact of acute post-operative pain after intracranial neurosurgeries.

Materials and Methods

This prospective observational study was conducted in adult patients undergoing intracranial neurosurgeries. After patient consent, ethics committee approval, and study registration, we assessed the incidence of post-operative pain using numerical rating scale (NRS) score. Predictors and impact of pain on patient outcomes were also evaluated.

Results

A total of 497 patients were recruited during 10-month study period. Significant (4-10 NRS score) post-operative pain at any time-point during the first 3 days after intracranial neurosurgery was reported by 65.5% (307/469) of patients. Incidence of significant pain during the 1st post-operative h, on the 1st, 2nd, and 3rd post-operative days was 20% (78/391), 50% (209/418), 38% (152/401), and 24% (86/360), respectively. Higher pre-operative NRS score and pain during the 1st h post-operatively, predicted the occurrence of pain during the first 3 days after surgery, P = 0.003 and P < 0.001, respectively. Pain was significantly associated with poor sleep quality on the first 2 post-operative nights (P < 0.001). Patient satisfaction score was higher in patients with post-operative pain, P = 0.002.

Conclusion

Every two in three patients undergoing elective intracranial neurosurgery report significant pain at some point during the first 3 postoperative days. Pre-operative pain and pain during 1st post-operative h predict the occurrence of significant post-operative pain.

Ultrasound-Guided Occipital Nerve Blocks as Part of Multi-Modal Perioperative Analgesia in Pediatric Posterior Craniotomies: A Case Series

Various regional anesthetics have been used for postoperative analgesia for pediatric craniotomy. In this case series, we report retrospectively collected data on postoperative pain and analgesic use in 44 patients who received ultrasound-guided occipital nerve blocks in addition to intravenous analgesic agents for posterior craniotomy procedures. In the immediate post-anesthesia care unit, pain was rated as zero or well controlled in 77% of patients, with only 43% requiring intravenous or demand patient-controlled analgesia opioids. There were no block-related complications. Occipital nerve blocks may constitute a safe and effective component of multimodal analgesia in this population.

Prevention of Post-Operative Pain after Elective Brain Surgery: A Meta-Analysis of Randomized Controlled Trials

Background and Objective: To analyze the effects of several drug for pain prevention in adults undergoing craniotomy for elective brain surgery. Material and Methods: A systematic review and meta-analysis were conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. The inclusion criteria were limited to randomized controlled trials (RCTs) that evaluated the effectiveness of pharmacological treatments for preventing post-operative pain in adults (aged 18 years or older) undergoing craniotomies. The main outcome measures were represented by the mean differences in validated pain intensity scales administered at 6 h, 12 h, 24 h and 48 h post-operatively. The pooled estimates were calculated using random forest models. The risk of bias was evaluated using the RoB2 revised tool, and the certainty of evidence was assessed according to the GRADE guidelines. Results: In total, 3359 records were identified through databases and registers' searching. After study selection, 29 studies and 2376 patients were included in the meta-analysis. The overall risk of bias was low in 78.5% of the studies included. The pooled estimates of the following drug classes were provided: NSAIDs, acetaminophen, local anesthetics and steroids for scalp infiltration and scalp block, gabapentinoids and agonists of adrenal receptors. Conclusions: High-certainty evidence suggests that NSAIDs and acetaminophen may have a moderate effect on reducing post-craniotomy pain 24 h after surgery compared to control and that ropivacaine scalp block may have a bigger impact on reducing post-craniotomy pain 6 h after surgery compared to control. Moderate-certainty evidence indicates that NSAIDs may have a more remarkable effect on reducing post-craniotomy pain 12 h after surgery compared to control. No moderate-to-high-certainty evidence indicates effective treatments for post-craniotomy pain prevention 48 h after surgery.

Association of scalp block with intraoperative hemodynamic profiles and postoperative pain outcomes at 24-48 hours following craniotomy: An updated systematic review and meta-analysis of randomized controlled studies

BACKGROUND

Despite the demonstrated analgesic efficacy of scalp block (SB) during the immediate postoperative period, the impact of SB on pain outcomes at postoperative 24 and 48 h in adults receiving craniotomy remains unclear.

METHODS

The databases of Medline, Embase, and Cochrane Central Register were searched from inception to January 2022 for available randomized controlled trials (RCTs). The primary outcome was the severity of pain at postoperative 24 and 48 h, while the secondary outcomes included morphine consumption, hemodynamic profiles after surgical incision and in the postanesthesia care unit (PACU), and risk of postoperative nausea/vomiting (PONV).

RESULTS

Meta-analysis of 12 studies revealed a lower pain score [MD = -0.83, p = 0.03, 375 patients, certainty of evidence (COE): low] and morphine consumption (MD = -9.21 mg, p = 0.03, 246 patients, COE: low) at postoperative 24 h, while there were no differences in these pain outcomes at postoperative 48 h (COE: low). The use of SB significantly decreased intraoperative heart rate (MD = -10.9 beats/min, p < 0.0001, 189 patients, COE: moderate) and mean blood pressure (MD = -13.02 mmHg, p < 0.00001, 189 patients, COE: moderate) after surgical incision, but these hemodynamic profiles were comparable in both groups in the PACU setting. There was also no difference in the risk of PONV between the two groups (RR = 0.78, p = 0.2, 299 patients, COE: high).

CONCLUSION

This meta-analysis demonstrated that scalp block not only provided hemodynamic stability immediately after surgical incision but was also associated with a lower pain score and morphine consumption at postoperative 24 h. Further studies are needed for elucidation of its findings.

Anesthesia and analgesia for experimental craniotomy in mice and rats: a systematic scoping review comparing the years 2009 and 2019

Experimental craniotomies are a common surgical procedure in neuroscience. Because inadequate analgesia appears to be a problem in animal-based research, we conducted this review and collected information on management of craniotomy-associated pain in laboratory mice and rats. A comprehensive search and screening resulted in the identification of 2235 studies, published in 2009 and 2019, describing craniotomy in mice and/or rats. While key features were extracted from all studies, detailed information was extracted from a random subset of 100 studies/year. Reporting of perioperative analgesia increased from 2009 to 2019. However, the majority of studies from both years did not report pharmacologic pain management. Moreover, reporting of multimodal treatments remained at a low level, and monotherapeutic approaches were more common. Among drug groups, reporting of pre- and postoperative administration of non-steroidal anti-inflammatory drugs, opioids, and local anesthetics in 2019 exceeded that of 2009. In summary, these results suggest that inadequate analgesia and oligoanalgesia are persistent issues associated with experimental intracranial surgery. This underscores the need for intensified training of those working with laboratory rodents subjected to craniotomies.

Systematic review registration

https://osf.io/7d4qe.

The Prevalence and Factors Associated with the Prescription of Opioids for Head/Neck Pain after Elective Craniotomy for Tumor Resection/Vascular Repair: A Retrospective Cohort Study

Background and objective: There is no report of the rate of opioid prescription at the time of hospital discharge, which may be associated with various patient and procedure-related factors. This study examined the prevalence and factors associated with prescribing opioids for head/neck pain after elective craniotomy for tumor resection/vascular repair. Methods: We performed a retrospective cohort study on adults undergoing elective craniotomy for tumor resection/vascular repair at a large quaternary-care hospital. We used univariable and multivariable analysis to examine the prevalence and factors (pre-operative, intraoperative, and postoperative) associated with prescribing opioids at the time of hospital discharge. We also examined the factors associated with discharge oral morphine equivalent use. Results: The study sample comprised 273 patients with a median age of 54 years [IQR 41,65], 173 females (63%), 174 (63.7%) tumor resections, and 99 (36.2%) vascular repairs. The majority (n = 264, 96.7%) received opioids postoperatively. The opiate prescription rates were 72% (n = 196/273) at hospital discharge, 23% (19/83) at neurosurgical clinical visits within 30 days of the procedure, and 2.4% (2/83) after 30 days from the procedure. The median oral morphine equivalent (OME) at discharge use was 300 [IQR 175,600]. Patients were discharged with a median supply of 5 days [IQR 3,7]. On multivariable analysis, opioid prescription at hospital discharge was associated with pre-existent chronic pain (adjusted odds ratio, aOR 1.87 [1.06,3.29], p = 0.03) and time from surgery to hospital discharge (compared to patients discharged within days 1−4 postoperatively, patients discharged between days 5−12 (aOR 0.3, 95% CI [0.15; 0.59], p = 0.0005), discharged at 12 days and later (aOR 0.17, 95% CI [0.07; 0.39], p < 0.001)). There was a linear relationship between the first 24 h OME (p < 0.001), daily OME (p < 0.001), hospital OME (p < 0.001), and discharge OME. Conclusions: This single-center study finds that at the time of hospital discharge, opioids are prescribed for head/neck pain in as many as seven out of ten patients after elective craniotomy. A history of chronic pain and time from surgery to discharge may be associated with opiate prescriptions. Discharge OME may be associated with first 24-h, daily OME, and hospital OME use. Findings need further evaluation in a large multicenter sample. The findings are important to consider as there is growing interest in an early discharge after elective craniotomy.

Postoperative Analgesic Efficacy and Safety of Ropivacaine Plus Diprospan for Preemptive Scalp Infiltration in Patients Undergoing Craniotomy: A Prospective Randomized Controlled Trial

BACKGROUND

Preemptive injection of local anesthetics can prevent postoperative pain at the incision site, but the analgesic effect is insufficient and is maintained only for a relatively short period of time. Diprospan is a combination of quick-acting betamethasone sodium phosphate and long-acting betamethasone dipropionate. Whether Diprospan as an adjuvant to local anesthetic can achieve postcraniotomy pain relief has not been studied yet.

METHODS

This is a prospective, single-center, blinded, randomized, controlled clinical study, which included patients ages 18 and 64 years, with American Society of Anaesthesiologists (ASA) physical statuses of I to III, scheduled for elective supratentorial craniotomy. We screened patients for enrollment from September 3, 2019, to August 15, 2020. The final follow-up was completed on February 15, 2021. Eligible patients were randomly assigned to either the Diprospan group, who received incision-site infiltration of 0.5% ropivacaine plus Diprospan (n = 48), or the control group, who received 0.5% ropivacaine alone (n = 48), with a distribution ratio of 1:1. Primary outcome was the cumulative sufentanil (μg) consumption through patient-controlled analgesia (PCA) within 48 hours after surgery. Primary analysis was performed based on the intention-to-treat (ITT) principle.

RESULTS

Baseline characteristics were not significantly different between the 2 groups ( P > .05). In the Diprospan group, the cumulative sufentanil consumption through PCA was 5 (0-16) µg within 48 hours postoperatively, which was significantly lower than that in the control group (38 [30.5-46] µg; P < .001).

CONCLUSIONS

Infiltration of ropivacaine and Diprospan can achieve satisfactory postoperative pain relief after craniotomy; it is a simple, easy, and safe technique, worth clinical promotion.

Pain Behaviors Analyzed by Videorecording in Brain-Injured Patients Admitted to the Intensive Care Unit

AIM

To describe and classify pain behaviors (facial and body) in brain-injured patients with a low level of consciousness before, during, and after the performance of painful and non-painful care procedures.

METHODS

Facial behaviors and body movements in brain-injured patients were videotaped at rest, during the application of three care procedures (two painful and one non-painful), and 15 minutes after completion of these procedures. Each video recording was evaluated by expert evaluators blinded to each other. For each of the behaviors observed, all possible combinations between the three procedures and/or time were compared using the McNemar test. Effect size was measured by the difference in proportions using the Wilson score 95% confidence intervals.

RESULTS

Twenty-seven patients were included. The mean (standard deviation) Glasgow Coma Score was 5.4 (1.9). A total of 33 behaviors (29 active, four neutral) were registered. Expression of behaviors was more common during the painful procedures compared with the other time points (non-painful procedures, baseline, and final evaluation). Inter-evaluator agreement was substantial (Kappa index >0.7) in more than 50% of the observed behaviors.

CONCLUSIONS

In this study involving brain-injured patients with a low level of consciousness, facial, body, and ventilation-related behaviors were more common during painful procedures. Agreement between evaluators to detect the presence or absence of these behaviors was substantial. These findings underscore the need to develop pain assessment measures specific to this patient population.

Nonsteroidal antiinflammatory drugs versus tramadol in pain management following transsphenoidal surgery for pituitary adenomas: a randomized, double-blind, noninferiority trial

OBJECTIVE

Opioid-minimizing or nonopioid therapy using nonsteroidal antiinflammatory drugs (NSAIDs) or tramadol has been encouraged for pain management. This study aimed to examine the noninferiority of NSAIDs to tramadol for pain management following transsphenoidal surgery for pituitary adenomas in terms of analgesic efficacy, adverse events, and rescue opioid use.

METHODS

This was a randomized, single-center, double-blind noninferiority trial. Patients 18-70 years old with planned transsphenoidal surgery for pituitary adenomas were randomly assigned (in a 1-to-1 ratio) to receive NSAIDs (parecoxib injection and subsequent loxoprofen tablets) or tramadol (tramadol injection and subsequent tramadol tablets). The primary outcome was pain score assessed by a visual analog scale (VAS) for 24 hours following surgery; the secondary outcomes were VAS scores for 48 and 72 hours. Other prespecified outcomes included nausea, vomiting, dizziness, upset stomach, skin rash, peptic ulcer, gastrointestinal bleeding, and pethidine use to control breakthrough pain. Noninferiority of NSAIDs to tramadol was established if the upper limit of the 95% confidence interval (CI) of the VAS score difference was < 1 point and the rate difference of adverse events and pethidine use < 5%. The superiority of NSAIDs was assessed when noninferiority was verified. All analyses were performed on an intention-to-treat basis.

RESULTS

Two hundred two patients were enrolled between November 1, 2020, and May 31, 2021 (101 in the NSAIDs group, 101 in the tramadol group). Baseline characteristics between groups were well balanced. Mean VAS scores for 24 hours following transsphenoidal surgery were 2.6 ± 1.8 in the NSAIDs group and 3.5 ± 2.1 in the tramadol group (-0.9 difference, 95% CI -1.5 to -0.4; p value for noninferiority < 0.001, p value for superiority < 0.001). Noninferiority and superiority were also achieved for both secondary outcomes. VAS scores improved over time in both groups. Incidences of nausea (39.6% vs 61.4%, p = 0.002), vomiting (3.0% vs 42.6%, p < 0.001), and dizziness (12.9% vs 47.5%, p < 0.001) were significantly lower, while incidence of upset stomach (9.9% vs 2.0%, p = 0.017) was slightly higher in the NSAIDs group compared with the tramadol group. The percentage of opioid use was 4.0% in the NSAIDs group and 15.8% in the tramadol group (-11.8% difference, 95% CI -19.9% to -3.7%; p value for noninferiority < 0.001, p value for superiority = 0.005).

CONCLUSIONS

NSAIDs significantly reduced acute pain following transsphenoidal surgery, caused few adverse events, and limited opioid use compared with tramadol.

Pneumocephalus and headache following craniotomy during the immediate postoperative period

Background

Pneumocephalus may be responsible for post-craniotomy headache but is easily overlooked in the clinical situation. In the present study, the relationship between the amount of intracranial air and post-craniotomy headache was investigated.

Methods

A retrospective observational study was performed on 79 patients who underwent minimal invasive craniotomy for unruptured cerebral aneurysms. Those who had undergone previous neurosurgery, neurological deficit before and after surgery were excluded The amount of air in the cranial cavity was measured using brain computed tomography (CT) taken within 6 h after surgery. To measure the degree of pain due to intracranial air, daily and total analgesic administration amount were used as a pain index. Correlation between intracranial air volume and total consumption of analgesic during hospitalization was tested using Spearman rank correlation coefficients. Receiver operating characteristics (ROC) analysis was used to determine the amount of air associated with increased analgesic consumption over 72 h postoperatively.

Results

The mean amount of intracranial air was 15.6 ± 9.1 mL. Total administration of parenteral and oral analgesics frequency were 6.5 ± 4.5, 13.2 ± 7.9 respectively. A statically significant correlation was observed between daily and total parenteral analgesic consumption after surgery and the amount of intracranial air at followed-up brain CT postoperatively within 24 h (r = 0.69, p < 0.001), within 48 h (r = 0.68, p < 0.001), and total duration after surgery (r = 0.84, p < 0.001). The optimal cut-off value of 12.14 mL of intracranial air predicts the use of parenteral analgesics over 72 h after surgery.

Conclusions

Pneumocephalus may be a causative factor for post-craniotomy pain and headache with surgical injuries.

Multimodal analgesia in neurosurgery: a narrative review

Pain following brain surgery can compromise the result of surgery. Several pharmacological interventions have been used to prevent postoperative pain in adults undergoing brain surgery. Pain following craniotomy is considered to be moderate to severe during the first two post-operative days. Opioids have been historically the mainstay and are the current prominent strategy for pain treatment. They produce analgesia but may alter respiratory, cardiovascular, gastrointestinal, and neuroendocrine functions. All these side effects may affect the normal postoperative course of craniotomy by affecting neurological function and increasing intracranial pressure. Therefore, their use in neurosurgery is limited, and opioids are used in case of strict necessity or as rescue medication. In addition to opioids, drugs with differing mechanisms of actions target pain pathways, resulting in additive and/or synergistic effects. Some of these agents include acetaminophen/non-steroidal anti-inflammatory drugs (NSAIDs), alpha-2 agonists, NMDA receptor antagonists, gabapentinoids, and local anesthesia techniques. Multimodal analgesia should be a balance between adequate analgesia and less drug-induced sedation, respiratory depression, hypercapnia, nausea, and vomiting, which may increase intracranial pressure. Non-opioid analgesics can be an useful pharmacological alternative in multimodal regimes to manage post-craniotomy pain. This narrative review aims to outline the current clinical evidence of multimodal analgesia for post craniotomy pain control.

Effects of Intraoperative Dexmedetomidine Infusion on Postoperative Pain after Craniotomy: A Narrative Review

Craniotomy involves procedures with high incidences of postoperative pain. Dexmedetomidine, a highly selective a₂-adrenoreceptor agonist, has been shown to be beneficial in neuroanaesthesia. The purpose of this narrative review was to assess the effect and safety of dexmedetomidine given intraoperatively during anaesthesia compared to placebo and demonstrate the effect on acute postoperative pain in adult patients undergoing craniotomy. Literature published from 1996 until 2021 were analysed through a search of PubMed, Medline and Embase. Randomised controlled trials investigating intraoperative administration of Dexmedetomidine with evaluation of postoperative pain were included. Medical Subject Headings terms and free-text words were used to identify articles related to the intraoperative use of Dexmedetomidine and postcraniotomy pain. Thirteen distinct randomized controlled trials with 882 recruited patients undergoing craniotomy were identified as eligible for final inclusion. Intraoperative administration of dexmedetomidine is associated with decreased postoperative pain and opioid consumption, and it assures haemodynamic stability. Dexmedetomidine is an efficacious adjunct in craniotomy in adults, showing benefits in reduction of postoperative pain and analgesic consumption. Dexmedetomidine also offers haemodynamic stability. However, widespread methodological heterogeneity of the papers prohibits a valid meta-analysis.

Dexmedetomidine vs. lidocaine for postoperative analgesia in pediatric patients undergoing craniotomy: a protocol for a prospective, randomized, double-blinded, placebo-controlled trial

Background

Postoperative pain is a common problem that occurs in pediatric patients following neurosurgery which may lead to severe complications. Dexmedetomidine is a commonly used adjuvant medicine in craniotomy owing to its sedative, amnestic, analgesic, and neuroprotective properties. Besides, studies suggest that lidocaine has similar effects on sedation, analgesia, and neuroprotection. Both two adjuvants can reduce postoperative pain after neurosurgery in adults. However, it is still unknown whether dexmedetomidine or lidocaine can reduce postoperative pain in children undergoing craniotomy, and if yes, which is a better medicine choice. Therefore, we aimed to compare the effect of dexmedetomidine vs. lidocaine on postoperative pain in pediatric patients after craniotomy.

Methods/design

We will perform a randomized (1:1:1), double-blind, placebo-controlled, single-center trial. Children aged 1–12 years scheduled for craniotomy will be eligible for inclusion. The 255 recruited participants will be stratified by age in two strata (1–6 years and 7–12 years), and then each stratum will be equally randomized to three groups: group D (infusion of dexmedetomidine [intervention group]), group L (infusion of lidocaine [intervention group]), and group C (infusion of normal saline [control group]). Patients will be followed up at 1 h, 2 h, 4 h, 24 h, and 48 h after surgery. The primary outcome will be total sufentanil consumption within 24 h after surgery.

Discussion

In this clinical trial, we expect to clarify and compare the postoperative analgesic effect of dexmedetomidine vs. lidocaine infusion on pediatric patients undergoing craniotomy. We believe that the results of this trial will provide more choices for postoperative analgesia for the pediatric population.

Trial registration

Chinese ClinicalTrials.gov ChiCTR1800019411. Registered on 10 November 2018

REDUCE trial: the effects of perineural dexamethasone on scalp nerve blocks for relief of postcraniotomy pain-a study protocol for a randomized controlled trial

BACKGROUND

Pain is common in the first 2 days after major craniotomy. Inadequate analgesia may lead to an increased risk of postoperative complications. Most pain following craniotomy arises from the pericranial muscles and soft tissues of the scalp. Scalp nerve blocks with local anesthesia seem to provide effective, safe, however, transient postoperative analgesia which does not seem to meet the requirements of craniotomy. Currently, peripheral dexamethasone has been observed to significantly prolong the duration of analgesia of nerve blocks (e.g., saphenous nerve block, adductor canal block, thoracic paravertebral block, brachial plexus nerve block). On the contrary, a study reported that perineural dexamethasone did not appear to prolong the analgesic time after supratentorial craniotomy. However, all patients in this study were given 24 mg of oral or intravenous dexamethasone regularly for at least 7 days during the perioperative period, which possibly masked the role of single local low doses of perineural dexamethasone. Therefore, the analgesic effect of single dexamethasone for scalp nerve blocks without the background of perioperative glucocorticoid deserves further clarification.

METHODS

The REDUCE trial is a prospective, single-center, parallel-group randomized controlled trial involving a total of 156 adults scheduled for elective craniotomy with general anesthesia. Patients will be randomly divided among two groups: the control group (n = 78) will receive scalp nerve blocks with 0.5% bupivacaine, plus normal saline with epinephrine at 1:200,000; the DEX_4mg group (n = 78) will receive scalp nerve blocks with 0.5% bupivacaine, plus 4 mg dexamethasone with epinephrine at 1:200,000. The primary outcome will be the duration of analgesia, defined as the time between the performance of the block and the first analgesic request.

DISCUSSION

The REDUCE trial aims to further assess the analgesic effect of single dexamethasone as an adjuvant to scalp nerve blocks for relief of postcraniotomy pain without the background of perioperative glucocorticoid.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04648358 . Registered on November 30, 2020.

Preoperative Versus Postoperative Scalp Block Combined With Incision Line Infiltration for Pain Control After Supratentorial Craniotomy

OBJECTIVE

Postoperative pain after craniotomy is a significant clinical problem that is sometimes underestimated, although moderate or severe pain in early postoperative period complicates up to 60% of cases. The purpose of this prospective randomized multicenter trial was to determine the optimal timing for selective scalp block in patients undergoing general anesthesia for supratentorial craniotomy.

MATERIALS AND METHODS

After ethics committee approval and informed consent, 56 adult patients were enrolled, and randomly assigned to receive a selective scalp block combined with incision line infiltration preoperatively or postoperatively.

RESULTS

Postoperative pain at 24 hours after the procedure was recorded in all 56 enrolled patients. In patients assigned to receive a scalp block preoperatively, median VAS score at 24 hours after surgery was 0 (0 to 2), and in patients assigned to receive a scalp block postoperatively it was 0 (0 to 3) (P>0.05). There was no difference in severity of pain at 24, 12, 6, and 2 hours after surgery between the 2 study groups, but the amount of fentanyl administered intraoperatively was lower in patients assigned to the preoperative scalp block group (1.6±0.7 vs. 2.4±0.7 mkg/kg/h, P=0.01).

DISCUSSION

This study confirms and extends available clinical evidence on the safety and efficacy of selective scalp blocks for the prevention of postoperative pain. Recorded data suggest that there is no difference in terms of occurrence and severity of postoperative pain regardless of whether the scalp block is performed preoperatively (after general anesthesia induction) or postoperatively (before extubation). Patients assigned to receive a scalp block combined with incision line infiltration preoperatively needed less intraoperative opioids than those assigned to postoperative scalp block.

Pain Management Experiences Among Hospitalized Postcraniotomy Brain Tumor Patients

BACKGROUND

Brain tumors account for the majority of central nervous system tumors, and most are removed by craniotomies. Many postcraniotomy patients experience moderate or severe pain after surgery, but patient perspectives on their experiences with pain management in the hospital have not been well described.

OBJECTIVE

The aim of this study was to describe how patients who have undergone a craniotomy for brain tumor removal experience pain management while hospitalized.

METHODS

Qualitative descriptive methods using semistructured interviews were conducted with patients on a neurological step-down unit in an urban teaching hospital in the Midwest United States. Interviews focused on how patients experienced postcraniotomy pain and how it was managed. Narratives were analyzed with standard content analytic procedures.

RESULTS

Twenty-seven participants (median age, 58.5 years; interquartile range, 26-41 years; range, 21-83 years) were interviewed. The majority were white (n = 25) and female (n = 15) and had an anterior craniotomy (n = 25) with sedation (n = 17). Their pain experiences varied on 2 dimensions: salience of pain during recovery and complexity of pain management. Based on these dimensions, 3 distinct types of pain management experiences were identified: (1) pain-as-nonsalient, routine pain management experience; (2) pain-as-salient, routine pain management experience; and (3) pain-as-salient, complex pain management experience.

CONCLUSIONS

Many postcraniotomy patients experience their pain as tolerable and/or pain management as satisfying and effective; others experience pain and pain management as challenging.

IMPLICATIONS FOR PRACTICE

Clinicians should be attuned to needs of patients with complex pain management experiences and should incorporate good patient/clinician communication.

Pre-Emptive Incision-Site Infiltration with Ropivacaine Plus Dexamethasone for Postoperative Pain After Supratentorial Craniotomy: A Prospective Randomized Controlled Trial

Background

Incision-site infiltration with local anesthetics prevents pain on incision site, but pain relief is limited to the first few postoperative hours. Dexamethasone as an adjuvant to local infiltration successfully achieves better postoperative pain relief; however, this has not been studied in craniotomy patients yet.

Study Design and Methods

This is a prospective, single-center, blinded, randomized, controlled trial included patients aged between 18 and 64 years, ASA physical status of I–II, scheduled for elective supratentorial tumor craniotomy under general anesthesia. We screened patients for enrollment from April 4, 2019 through August 15, 2019. The final study visit of the last patient was conducted on February 13, 2020. We randomly assigned eligible participants (1:1) to either the dexamethasone group who received incision-site infiltration of 0.5% ropivacaine plus 0.033% dexamethasone (N=70) or the control group who received 0.5% ropivacaine alone (N=70). Primary outcome was the cumulative sufentanil consumption (μg) within 48 hours postoperatively. Primary analysis was performed based on the modified intention-to-treat (MITT) principle.

Results

Baseline characteristics were similar between the groups (p>0.05). Sufentanil consumption during the first 48 hours postoperatively was 29.0 (10.7) μg in the dexamethasone group and 38.3 (13.7) μg in the control group (mean difference −9.3, 95% CI −13.4 to −5.1; p<0.001). There was no serious adverse effect directly associated with incision-site infiltration or local dexamethasone use.

Conclusion

The addition of dexamethasone to pre-emptive incision-site infiltration with the local anesthetic can reduce about 27% of opioids consumption and the postoperative pain scores within 72 hours after craniotomy.

Trial Registration

ClinicalTrials.Gov (NCT03618264).

Behavioral and Physiological Pain Responses in Brain-Injured Patients Who Are Unable to Communicate in the Intensive Care Unit

BACKGROUND

Assessing pain of critically ill patients with brain injuries who are unable to communicate is a challenge. Current behavioral scales are limited in accurate pain assessments for this population.

AIMS

This study sought to investigate the behavioral and physiological responses induced by routine painful procedures in patients with brain injuries who are unable to communicate.

METHODS

Using a repeated-measure within-subject observational study design, 12 participants admitted to an intensive care unit were observed before, during, and 15 minutes after a nonnociceptive (noninvasive blood pressure measurement) procedure and three nociceptive (suctioning, turning, and trapezius pinch) procedures. During each assessment, patients' behavioral and physiological responses were observed using video cameras and bedside monitors.

RESULTS

In the overall behavioral responses to the nociceptive procedures, clenched teeth with tense jaw, frowning, orbit tightening, closing of eyes, eye movement, fixation-staring, flushing, flexion withdrawal of arm, flexion withdrawal of leg, muscle rigidity, twitching, and coughing were more frequently observed during procedures than before and after procedures (p < .01). Regarding physiological responses, significant increases in systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate, and respiratory rate were identified across assessments (p < .001).

CONCLUSIONS

The findings can be used as a basis for pain assessment and the development of pain assessment tools for brain-injured patients who are unable to communicate. However, since physiological responses may be influenced by various factors besides pain, physiological changes may be used as a sign of the need for pain assessment rather than being used alone as a basis for pain assessment.

Application of the Behavioural Indicators of Pain Scale in patients with traumatic brain injury

AIM

To develop and psychometrically test the Behavioural Indicators of Pain Scale (ESCID) in patients with traumatic brain injury (TBI).

DESIGN

A prospective observational study to test the psychometric properties of the Behavioural Indicators of Pain Scale in patients with TBI.

METHOD

A convenience sample of patients with TBI, who were non-communicative and using invasive mechanical ventilation was selected. Pain was evaluated by two observers who were blinded from each other. Assessments were performed at baseline via the performance of a painful procedure (aspiration of secretions) and a non-painful procedure (rubbing with a gauze). Assessments were repeated after application of procedures on days 1 and 6 of hospitalization in an intensive care unit. Data were collected between January-December 2016.

RESULTS

About 134 patients were included in the study. Of these, 76.1% were men. The mean age of participants was 45.2 (SD 17.5) years. The pain score significantly increased during the painful procedure when compared with the baseline measure and non-painful procedure (p < .001). Patients displayed a greater number of pain-indicating behaviours during the painful procedure on day 6, compared with day 1 (p < .05). This finding coincided with a reduced level of sedation and a greater level of consciousness.

CONCLUSION

The ESCID scale detects pain behaviours and discriminates among the different types of stimulation in patients with brain injury, who are uncommunicative and with mechanical ventilation, with good reliability. The ability for patients with brain injury to express behaviours is limited because of the low level of consciousness and the deep level of sedation.

IMPACT

This research will have an impact on the practice of pain assessment in patients with brain injury, representing a first step to adapt the content of the ESCID.

Effect of bilateral scalp nerve blocks on postoperative pain and discharge times in patients undergoing supratentorial craniotomy and general anesthesia: a randomized-controlled trial

PURPOSE

Post-craniotomy pain is a common clinical issue and its optimal management remains incompletely studied. Utilization of a regional scalp block has the potential advantage of reducing perioperative pain and opioid consumption, thereby facilitating optimal postoperative neurologic assessment. The purpose of this study was to assess the efficacy of regional scalp block on post-craniotomy pain and opioid consumption.

METHODS

We performed a prospective randomized-controlled trial in adults scheduled to undergo elective supratentorial craniotomy under general anesthesia to assess the efficacy of postoperative bilateral scalp block with 0.5% bupivacaine with 1:200,000 epinephrine compared with placebo on postoperative pain and opioid consumption. The primary outcome was the visual analogue scale (VAS) for pain at 24 hr postoperatively.

RESULTS

Eighty-nine patients were enrolled (n = 44 in block group; n = 45 in control group). There was no difference in the mean (standard deviation) VAS score at 24 hr postoperatively between the treatment group and the control group [31.2 (21.4) mm vs 23.0 (19.2) mm, respectively; mean difference, 6.6; 95% confidence interval, -2.3, 15.5; P = 0.15]. There was also no significant difference in postoperative opioid consumption. Distribution of individual VAS score and opioid consumption revealed that postoperative pain was highly variable following craniotomy. Time to hospital discharge was not different between treatment and placebo groups. No adverse events associated with scalp block were identified.

CONCLUSION

These data show that bilateral scalp blocks using bupivacaine with epinephrine did not reduce mean postoperative VAS score or overall opioid consumption at 24 hr nor the time-to-discharge from the postanesthesia care unit or from hospital.

TRIAL REGISTRATION

www.ClinicalTrials.gov, NCT00972790; registered 9 September, 2009.

Anesthesia for meningioma surgery

Patients receiving treatment for a meningioma require anesthesia when undergoing open craniotomy and, in some cases, during preoperative tumor embolization and radiosurgery. Adequate anesthesia management is integral to patients' perioperative care, which consists of the three phases of preoperative assessment and optimization, intraoperative care, and postoperative recovery. The preoperative anesthesia evaluation focusses on the cardiorespiratory and neurologic systems, as well as the airway, but also extends to ensure the optimal treatment of significant comorbidities before surgical intervention. The goals of intraoperative care are maintenance of brain physiology, facilitating surgery, and correcting any adverse effects of surgery and underlying pathology to preserve general patient homeostasis. This requires adequate intraoperative patient monitoring, cardiorespiratory support, management of infusion therapy, and application of knowledge about the effects of anesthetic agents on brain physiology. The anesthesiologist's responsibilities for patient care extend well into the postoperative recovery period, with a focus on pain control, prevention, and treatment of postoperative nausea and vomiting (PONV), and, in some patients, intensive care therapy.

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.

Subcutaneous sumatriptan for the treatment of postcraniotomy pain (SUPS trial): protocol for a randomised double-blinded placebo controlled trial

INTRODUCTION

Postcraniotomy pain protocols use opioids, which are considered suboptimal analgesia following this procedure. Multimodal analgesia components are sparse. Our null hypothesis states that sumatriptan is not different to placebo in addition to usual intravenous opioids, for the treatment of acute postcraniotomy pain.

METHODS AND ANALYSIS

This is a prospective single-centre randomised double-blinded placebo-controlled phase III clinical trial comparing subcutaneous sumatriptan injection in the recovery area with placebo for the treatment of postcraniotomy pain. Eligible adult patients (18 years and older) undergoing craniotomy will be identified preoperatively. Both patient groups will receive a subcutaneous injection at a point where recovery-nursing staff would initiate the usual intravenous opioid analgesia as per standardised pain management protocol. In both groups, further pain management will be followed by the usual intravenous opioid administration. Primary outcome will consist of the difference in pain experienced by the two groups of patients in recovery area 60 min after the study drug administration. Postcraniotomy pain will be measured at regular intervals using the Visual Analogue Scale (VAS) in recovery area. The minimal clinically important difference of 10 mm on the VAS between the two groups will be considered as statistically significant. We will include selected clinical and patient-reported outcomes as secondary endpoints. Univariate regression will be conducted on each one of the clinically plausible potential confounders. We will enrol a total 136 patients, with the study duration of 2 years. This trial will commence recruitment on the 1 July 2019.

ETHICS AND DISSEMINATION

This trial protocol has achieved approval by the Austin Health Research Committee, HREC/17/Austin/596. This trial was prospectively registered with Australian New Zealand Clinical Trials Registry on the 10/05/2018 with a unique trial identifier U1111-1209-9072 and registration Number ACTRN12618000793213P. Findings of this study will be disseminated in peer-reviewed academic journals.

TRIAL REGISTRATION NUMBER

U1111-1209-9072, ACTRN12618000793213P.

Opioid-Free Analgesia for Supratentorial Craniotomies: A Systematic Review

BACKGROUND

Post-craniotomy pain can be severe and is often undermanaged. Opioids can interfere with neurological monitoring and are associated with adverse effects. This systematic review aimed to identify measures of opioid-free analgesia and compare their effectiveness with opioid analgesia for post-craniotomy pain in patients with supratentorial tumors.

METHODS

EMBASE, MEDLINE, and Cochrane databases were searched from their inception to February 14, 2017, for randomized controlled trials (RCTs) evaluating opioid versus non-opioid analgesia post-supratentorial craniotomy. Two reviewers independently carried out study selection and data extraction. Risk of bias assessment was performed using the Cochrane Collaboration's tool. Outcomes were pain control (changes to pain scores or use of rescue analgesia) and adverse effects. Considering the number of studies and heterogeneity, a narrative synthesis was done without pooling and results were summarized using tables. Non-opioids were assessed for the potential to be equivalent to opioid-based analgesics for pain relief and adverse effects.

RESULTS

Of 467 RCTs, 4 met our inclusion criteria (n = 186 patients). Patients with scalp blocks (2 RCTs) had less post-operative nausea and vomiting (PONV), but scalp block was not superior to morphine for analgesia. Acetaminophen (1 RCT) was less likely to induce PONV but provided inadequate pain relief compared to morphine and sufentanil. Dexmedetomidine (1 RCT) was not superior to remifentanil for analgesia although it delayed time to rescue analgesia.

CONCLUSIONS

Limited evidence suggests that scalp blocks and dexmedetomidine have the potential to eliminate the need for opioid analgesia. Multimodal analgesia should be considered as significant opioid-sparing effects have been shown.

A comparison of effects of scalp nerve block and local anesthetic infiltration on inflammatory response, hemodynamic response, and postoperative pain in patients undergoing craniotomy for cerebral aneurysms: a randomized controlled trial

BACKGROUND

The purpose of this study was to compare the effects of scalp nerve block (SNB) and local anesthetic infiltration (LA) with 0.75% ropivacaine on postoperative inflammatory response, intraoperative hemodynamic response, and postoperative pain control in patients undergoing craniotomy.

METHODS

Fifty-seven patients were admitted for elective craniotomy for surgical clipping of a cerebral aneurysm. They were randomly divided into three groups: Group S (SNB with 15 mL of 0.75% ropivacaine), group I (LA with 15 mL of 0.75% ropivacaine) and group C (that only received routine intravenous analgesia). Pro-inflammatory cytokine levels in plasma for 72 h postoperatively, hemodynamic response to skin incision, and postoperative pain intensity were measured.

RESULTS

The SNB with 0.75% ropivacaine not only decreased IL-6 levels in plasma 6 h after craniotomy but also decreased plasma CRP levels and increased plasma IL-10 levels 12 and 24 h after surgery compared to LA and routine analgesia. There were significant increases in mean arterial pressure 2 and 5 mins after the incision and during dura opening in Groups I and C compared with Group S. Group S had lower postoperative pain intensity, longer duration before the first dose of oxycodone, less consumption of oxycodone and lower incidence of PONV through 48 h postoperatively than Groups I and C.

CONCLUSION

Preoperative SNB attenuated inflammatory response to craniotomy for cerebral aneurysms, blunted the hemodynamic response to scalp incision, and controlled postoperative pain better than LA or routine analgesia.

TRIAL REGISTRATION

Clinicaltrials.gov NCT03073889 (PI:Xi Yang; date of registration:08/03/2017).

Comparison of intraoperative fentanyl with dexmedetomidine for perioperative analgesia and opioid consumption during craniotomies: A randomised controlled pilot study with non-inferiority design

BACKGROUND

Moderate to severe pain is common despite the use of potent opioids during craniotomies. Non-opioid agents such as dexmedetomidine reduce undesirable opioid effects and are successfully used as primary analgesic during bariatric surgeries. This study assessed the feasibility of conducting a large randomised controlled trial comparing fentanyl with dexmedetomidine for perioperative analgesia during craniotomy.

METHODS

This was a prospective single-centre randomised controlled feasibility trial. Twenty-four consenting adult patients undergoing supratentorial craniotomy at NIMHANS, Bangalore, India, were recruited after ethical approval in March and April 2018. They received either fentanyl 1 µg kg^-1  h^-1 (n = 12) or dexmedetomidine 0.5  µg kg^-1  h^-1 (n = 12) as primary intraoperative analgesic drug. Patient, anaesthesiologist, outcome assessor and data analyst were blinded to the study intervention. Our feasibility outcomes (primary) were recruitment and adherence rates. We also explored the potential efficacy of intervention and adverse events.

RESULTS

We recruited 24 out of 30 eligible patients and had 100% protocol adherence, thereby demonstrating the feasibility of a larger randomised controlled trial. All 24 patients completed the study. The demographic and clinical parameters were similar between the groups. Compared between fentanyl and dexmedetomidine, there was no difference in the intraoperative fentanyl (top-up) consumption (µg), expressed as median and interquartile range: 25 (0-50) and 0 (0-50); P = 0.844; and no difference in postoperative pain at 15 and 60 minutes. Adverse events were few and similar with fentanyl and dexmedetomidine.

CONCLUSIONS

A large-scale randomised controlled trial of perioperative dexmedetomidine versus fentanyl is feasible. Dexmedetomidine has the potential to be non-inferior to fentanyl for perioperative analgesia during craniotomies.

Pain management in neurocritical care; an update

PURPOSE OF REVIEW

Pain management in neurocritical care is a subject often avoided because of concerns over the side-effects of analgesics and the potential to cause additional neurological injury with treatment. The sedation and hypercapnia caused by opioids have been feared to mask the neurological examination and contribute to elevations in intracranial pressure. Nevertheless, increasing attention to patient satisfaction has sparked a resurgence in pain management. As opioids have remained at the core of analgesic therapy, the increasing attention to pain has contributed to a growing epidemic of opioid dependence. In this review, we summarize the most recent literature regarding opioids and their alternatives in the treatment of acute pain in patients receiving neurocritical care.

RECENT FINDINGS

Studies on pain management in neurocritical care continue to explore nonopioid analgesics as part of a multimodal strategy aimed at decreasing overall opioid consumption. Agents including local anesthetics, acetaminophen, ketamine, gabapentinoids, and dexmedetomidine continue to demonstrate efficacy. In addition, the prolonged longitudinal course of many recent trials has also revealed more about the transition from acute to chronic pain following hospitalization.

SUMMARY

In an era of increasing attention to patient satisfaction mitigated by growing concerns over the harms imposed by opioids, alternative analgesic therapies are being investigated with promising results.

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.

Transition from acute to chronic pain after surgery

Over the past decade there has been an increasing reliance on strong opioids to treat acute and chronic pain, which has been associated with a rising epidemic of prescription opioid misuse, abuse, and overdose-related deaths. Deaths from prescription opioids have more than quadrupled in the USA since 1999, and this pattern is now occurring globally. Inappropriate opioid prescribing after surgery, particularly after discharge, is a major cause of this problem. Chronic postsurgical pain, occurring in approximately 10% of patients who have surgery, typically begins as acute postoperative pain that is difficult to control, but soon transitions into a persistent pain condition with neuropathic features that are unresponsive to opioids. Research into how and why this transition occurs has led to a stronger appreciation of opioid-induced hyperalgesia, use of more effective and safer opioid-sparing analgesic regimens, and non-pharmacological interventions for pain management. This Series provides an overview of the epidemiology and societal effect, basic science, and current recommendations for managing persistent postsurgical pain. We discuss the advances in the prevention of this transitional pain state, with the aim to promote safer analgesic regimens to better manage patients with acute and chronic pain.

Pain Assessment in Mechanically Ventilated, Noncommunicative Severe Trauma Patients

The aim of this study was to measure pain levels in noncommunicative patients with severe trauma who required tracheal suctioning and mobilization and to determine the utility of the Behavioral Indicators of Pain Scale (ESCID) in these cases. The pain scores for the procedures were recorded on Days 1, 3, and 6 of the patients' stay in the intensive care unit. These assessments were performed at 3 moments: before, during, and after the application of the procedures. Because of the longitudinal character of the study, data were fitted into a multivariate model using the Generalized Estimating Equations method. The sample of 124 patients comprised 77.4% males and 22.6% females with an average age of 45.93 (SD = 16.43) years. A significant increase (p < .01) in the ESCID score was observed during the application of the procedures that produced similar pain levels. Kappa coefficient value obtained for interobserver agreement of ESCID scale scores during the application of care procedures at the intervals being evaluated was greater than 0.84, which should be interpreted as almost perfect. The ESCID scores increased during 2 care procedures that are frequently carried out in intensive care units and indicated that they produced similar pain levels.

Strides Toward Better Understanding of Post-Traumatic Headache Pathophysiology Using Animal Models

PURPOSE OF REVIEW

In recent years, the awareness of the detrimental impact of concussion and mild traumatic brain injuries (mTBI) is becoming more apparent. Concussive head trauma results in a constellation of cognitive and somatic symptoms of which post-traumatic headache is the most common. Our understanding of post-traumatic headache is limited by the paucity of well validated, characterized, and clinically relevant animal models with strong predictive validity. In this review, we aim to summarize and discuss current animal models of concussion/mTBI and related data that start to shed light on the pathophysiology of post-traumatic headache.

RECENT FINDINGS

Each of the models will be discussed in terms of their face, construct, and predictive validity as well as overall translational relevance to concussion, mTBI, and post-traumatic headache. Significant contributions to the pathophysiology of PTH garnered from these models are discussed as well as potential contributors to the development of chronic post-traumatic headache. Although post-traumatic headache is one of the most common symptoms following mild head trauma, there remains a disconnect between the study of mild traumatic brain injury and headache in the pre-clinical literature. A greater understanding of the relationship between these phenomena is currently needed to provide more insight into the increasing frequency of this debilitating condition in both military and civilian populations.

Postoperative headache following treatment of vestibular schwannoma: A literature review

Vestibular schwannoma (VS) is a brain tumour arising from Schwann cells that is typically closely associated with the vestibulocochlear nerve. Post-operative headaches (POH) are a potentially common complication of surgery for VS. Greatly differing rates of POH have previously been reported, particularly with different surgical approaches. The aim of this review is to identify and summarise the available peer-reviewed evidence on rates of POH following operative (or radiosurgery) treatment for VS, in addition to information about the treatment and prognosis of POH in these patients. A systematic search was conducted of Pubmed, Medline, Scopus and EMBASE in April 2017 using the medical subject headings (acoustic neuroma OR vestibular schwannoma) AND headache. Eligibility determination and data extraction were performed in duplicate with standardised forms. POH is common following surgery for VS. Differing rates of POH have been reported with different management approaches, patient age and tumour size. There are relatively few studies that have directly compared the rates of POH with different surgical approaches. The retrosigmoid approach with craniotomy appears to have lower rates of POH than when the retrosigmoid approach is performed with craniectomy. Patients under the age of 65 and with tumours <1.5 cm in size appear to have a higher risk of POH. The most commonly documented management of POH involves simple analgesia, although the majority of patients report this treatment is of only minimal benefit. Further prospective studies comparing rates of POH following different surgical approaches and radiosurgery are required.

Local anesthetics for brain tumor resection: current perspectives

This review summarizes the added value of local anesthetics in patients undergoing craniotomy for brain tumor resection, which is a procedure that is carried out frequently in neurosurgical practice. The procedure can be carried out under general anesthesia, sedation with local anesthesia or under local anesthesia only. Literature shows a large variation in the postoperative pain intensity ranging from no postoperative analgesia requirement in two-thirds of the patients up to a rate of 96% of the patients suffering from severe postoperative pain. The only identified causative factor predicting higher postoperative pain scores is infratentorial surgery. Postoperative analgesia can be achieved with multimodal pain management where local anesthesia is associated with lower postoperative pain intensity, reduction in opioid requirement and prevention of development of chronic pain. In awake craniotomy patients, sufficient local anesthesia is a cornerstone of the procedure. An awake craniotomy and brain tumor resection can be carried out completely under local anesthesia only. However, the use of sedative drugs is common to improve patient comfort during craniotomy and closure. Local anesthesia for craniotomy can be performed by directly blocking the six different nerves that provide the sensory innervation of the scalp, or by local infiltration of the surgical site and the placement of the pins of the Mayfield clamp. Direct nerve block has potential complications and pitfalls and is technically more challenging, but mostly requires lower total doses of the local anesthetics than the doses required in surgical-site infiltration. Due to a lack of comparative studies, there is no evidence showing superiority of one technique versus the other. Besides the use of other local anesthetics for analgesia, intravenous lidocaine administration has proven to be a safe and effective method in the prevention of coughing during emergence from general anesthesia and extubation, which is especially appreciated after brain tumor resection.

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.

Use of Dexmedetomidine for Prophylactic Analgesia and Sedation in Patients With Delayed Extubation After Craniotomy: A Randomized Controlled Trial

Background:

We conducted a randomized trial to evaluate the efficacy and safety of dexmedetomidine for prophylactic analgesia and sedation in patients with delayed extubation after craniotomy.

Methods:

From June 2012 to July 2014, 150 patients with delayed extubation after craniotomy were randomized 1:1 and were assigned to the dexmedetomidine group that received a continuous infusion of 0.6 μg/kg/h (10 μg/mL) or the control group that received a maintenance infusion of 0.9% sodium chloride for injection. The mean percentage of time under optimal sedation (SAS3-4), the percentage of patients who required rescue with propofol/fentanyl, and the total dose of propofol/fentanyl required throughout the course of drug infusion, as well as VAS, HR, MAP, and SpO₂ were recorded.

Results:

The percentage of time under optimal sedation was significantly higher in the dexmedetomidine group than in the control group (98.4%±6.7% vs. 93.0%±16.2%, P=0.008). The VAS was significantly lower in the dexmedetomidine group than in the control group (1.0 vs. 4.0, P=0.000). The HR and mean BP were significantly lower in the dexmedetomidine group than in the control group at all 3 time points (before endotracheal suctioning, immediately after extubation, and 30 min after extubation). No significant difference in SpO₂ was observed between the 2 groups. For hemodynamic adverse events, patients in the dexmedetomidine group were more likely to develop bradycardia (5.3% vs. 0%, P=0.043) but had a lower likelihood of tachycardia (2.7% vs. 18.7%, P=0.002).

Conclusions:

Dexmedetomidine may be an effective prophylactic agent to induce sedation and analgesia in patients with delayed extubation after craniotomy. The use of dexmedetomidine (0.6 μg/kg/h) infusion does not produce respiratory depression, but may increase the incidence of bradycardia.