A comparison between sevoflurane and desflurane anesthesia in patients undergoing craniotomy for supratentorial intracranial surgery

Effect of desflurane anesthesia on flash visual evoked potential monitoring in patients undergoing spine surgery: study protocol for a randomized controlled trial

BACKGROUND

Flash visual evoked potentials (FVEPs) are a reliable method for protecting visual function during spine surgery in prone position. However, the popularization and application of FVEPs remain limited due to the unclear influence of various anesthetics on FVEPs. Exploring the effects of anesthetic drugs on FVEP and establishing appropriate anesthesia maintenance methods are particularly important for promoting and applying FVEP. According to the conventional concept, inhaled narcotic drugs significantly affect the success of FVEP monitoring, FVEP extraction, and interpretation. Nonetheless, our previous study demonstrated that sevoflurane-propofol balanced anesthesia was a practicable regimen for FVEPs. Desflurane is widely used in general anesthesia for its rapid recovery properties. As the effect of desflurane on FVEP remains unclear, this trial will investigate the effect of different inhaled concentrations of desflurane anesthesia on amplitude of FVEPs during spine surgery, aiming to identify more feasible anesthesia schemes for the clinical application of FVEP.

METHODS/ DESIGN

A total of 70 patients undergoing elective spinal surgery will be enrolled in this prospective, randomized controlled, open-label, patient-assessor-blinded, superiority trial and randomly assigned to the low inhaled concentration of desflurane group (LD group) maintained with desflurane-propofolremifentanil-balanced anesthesia or high inhaled concentration of desflurane group (HD group) maintained with desflurane-remifentanil anesthesia maintenance group at a ratio of 1:1. All patients will be monitored for intraoperative FVEPs, and the baseline will be measured half an hour after induction under total intravenous anesthesia (TIVA). After that, patients will receive 0.5 minimum alveolar concentration (MAC) of desflurane combined with propofol and remifentanil for anesthesia maintenance in the LD group, while 0.7-1.0 MAC of desflurane and remifentanil will be maintained in the HD group. The primary outcome is the N75-P100 amplitude 1 h after the induction of anesthesia. We intend to use the dual measure evaluation, dual data entry, and statistical analysis by double trained assessors to ensure the reliability and accuracy of the results.

DISCUSSION

This randomized controlled trial aims to explore the superiority effect of low inhaled concentration of desflurane combined with propofolremifentanil-balanced anesthesia versus high inhaled concentration of desflurane combined with remifentanil anesthesia on amplitude of FVEPs. The study is meant to be published in a peer-reviewed journal and might guide the anesthetic regimen for FVEPs. The conclusion is expected to provide high-quality evidence for the effect of desflurane on FVEPs and aim to explore more feasible anesthesia schemes for the clinical application of FVEPs and visual function protection.

TRIAL REGISTRATION

This study was registered on clinicaltrials.gov on July 15, 2022.

CLINICALTRIALS

gov Identifier: NCT05465330.

Prophylaxis for paediatric emergence delirium in desflurane-based anaesthesia: a network meta-analysis

PURPOSE

The prevalence of postoperative emergence delirium in paediatric patients (pedED) following desflurane anaesthesia is considerably high at 50-80%. Although several pharmacological prophylactic strategies have been introduced to reduce the risk of pedED, conclusive evidence about the superiority of these individual regimens is lacking. The aim of the current study was to assess the potential prophylactic effect and safety of individual pharmacotherapies in the prevention of pedED following desflurane anaesthesia.

METHODS

This frequentist model network meta-analysis (NMA) of randomized controlled trials (RCTs) included peer-reviewed RCTs of either placebo-controlled or active-controlled design in paediatric patients under desflurane anaesthesia.

RESULTS

Seven studies comprising 573 participants were included. Overall, the ketamine + propofol administration [odds ratio (OR) = 0.05, 95% confidence intervals (95%CIs) 0.01-0.33], dexmedetomidine alone (OR = 0.13, 95%CIs 0.05-0.31), and propofol administration (OR = 0.30, 95%CIs 0.10-0.91) were associated with a significantly lower incidence of pedED than the placebo/control groups. In addition, only gabapentin and dexmedetomidine were associated with a significantly higher improvement in the severity of emergence delirium than the placebo/control groups. Finally, the ketamine + propofol administration was associated with the lowest incidence of pedED, whereas gabapentin was associated with the lowest severity of pedED among all of the pharmacologic interventions studied.

CONCLUSIONS

The current NMA showed that ketamine + propofol administration was associated with the lowest incidence of pedED among all of the pharmacologic interventions studied. Future large-scale trials to more fully elucidate the comparative benefits of different combination regimens are warranted.

TRIAL REGISTRATION

PROSPERO CRD42021285200.

Comparison of the Effects of Desflurane and Sevoflurane on Variations in Salivary Melatonin and Sleep Disturbance After Total Knee Arthroplasty: A Single-center, Prospective, Randomized, Controlled, Open-label Study

PURPOSE

Anesthesia has been shown to disrupt the circadian rhythm. Recovery of the circadian rhythm after general anesthesia might help alleviate symptoms of insomnia and postoperative delirium. We hypothesized that recovery of the circadian rhythm is faster after total knee arthroplasty (TKA) with desflurane than with sevoflurane. This study compared the influence of sevoflurane versus desflurane anesthesia on the postoperative circadian rhythm of melatonin in adults undergoing TKA.

DESIGN

Single-center, prospective, randomized, controlled, open-label study.

METHODS

This study involved adult patients undergoing TKA at a university hospital in Japan from May 1, 2018 to December 31, 2019. The primary outcome of the study was the comparison of the effect of sevoflurane and desflurane on the circadian rhythm of salivary melatonin for 3 days postoperatively. The secondary outcomes were postoperative fatigue and sleep quality for 3 days postoperatively.

FINDINGS

Twenty-eight patients (American Society of Anesthesiologists physical status of I or II) were scheduled for TKA and randomized to receive sevoflurane (n = 14) or desflurane (n = 14) anesthesia. There was no significant difference in the melatonin concentration between the sevoflurane and desflurane groups. The salivary melatonin concentration after sevoflurane or desflurane anesthesia was significantly higher at 9:00 p.m. on a postoperative day (POD)0 and POD1 than on POD3 (P < .05). Patients in the desflurane group had significantly greater fatigue than those in the sevoflurane group at 7:00 a.m. and 12:00 p.m. on POD3 (P < .05). Patients in the sevoflurane group had a deeper sleep than those in the desflurane group on POD0 (P < .05). In the sevoflurane group, the sleep time during the night of POD2 was longer than that on POD0 (6.1 vs 4.2 hours, P < .05).

CONCLUSIONS

Under the current study conditions, desflurane was equivalent to sevoflurane in terms of the postoperative salivary melatonin concentration and sleep disturbance after TKA but not in terms of recovering the postoperative circadian rhythm.

Clinical Effects and Adverse Events Associated With Desflurane Use in Adult Patients Undergoing Supratentorial Craniotomy: A Systematic Review

Desflurane is an inhalational anesthetic agent with an appealing recovery profile. The present systematic review investigates the clinical effects and adverse events associated with desflurane use during supratentorial craniotomy for brain tumor resection in adults in comparison with other inhalational and intravenous anesthetic agents. A literature search was conducted across the MEDLINE, Library of Congress and LISTA (EBSCO) databases from January 2001 to January 2021. Twelve studies published between 2003 and 2020 were included in this systematic review. Desflurane was compared with either isoflurane, sevoflurane, or propofol for anesthesia maintenance. Brain relaxation scores showed no statistically significant difference between desflurane and the other anesthetic agents. Recovery timepoints, such as time to recovery, time to eye opening, time to extubation, time to follow commands, and time to reach a modified Aldrete score ≥9 were significantly shorter with desflurane in the majority of studies. Systemic hemodynamic variables (mean arterial pressure and heart rate) and cerebral hemodynamics (intracranial pressure and cerebrospinal fluid pressure) were comparable between desflurane and other anesthetic agents in each study. The results of this systematic review demonstrate that desflurane is associated with few adverse events when used for anesthesia maintenance in adult patients undergoing supratentorial brain tumor surgery. Large, prospective, comprehensive studies, utilizing standardized parameter evaluation could provide higher levels of evidence to support these findings.

Systematic review with meta-analysis of relative risk of prolonged times to tracheal extubation with desflurane versus sevoflurane or isoflurane

The objective of this systematic review was to estimate the relative risk of prolonged times to tracheal extubation with desflurane versus sevoflurane or isoflurane. Prolonged times are defined as ≥15 min from end of surgery (or anesthetic discontinuation) to extubation in the operating room. They are associated with reintubations, naloxone and flumazenil administration, longer times from procedure end to operating room exit, greater differences between actual and scheduled operating room times, longer times from operating room exit to next case start, longer durations of the workday, and more operating room personnel idle while waiting for extubation. Published randomized clinical trials of humans were included. Generalized pivotal methods were used to estimate the relative risk of prolonged extubation for each study from reported means and standard deviations of extubation times. The relative risks were combined using DerSimonian-Laird random effects meta-analysis with Knapp-Hartung adjustment. From 67 papers, there were 78 two-drug comparisons, including 5167 patients. Studies were of high quality (23/78) or moderate quality (55/78), the latter due to lack of blinding of observers to group assignment and/or patient attrition because patients were extubated after operating room exit. Desflurane resulted in a 65% relative reduction in the incidence of prolonged extubation compared with sevoflurane (95% confidence interval 49% to 76%, P < .0001) and in a 78% relative reduction compared with isoflurane (58% to 89%, P = .0001). There were no significant associations between studies' relative risks and quality, industry funding, or year of publication (all six meta-regressions P ≥ .35). In conclusion, when emergence from general anesthesia with different drugs are compared with sevoflurane or isoflurane, suitable benchmarks quantifying rapidity of emergence are reductions in the incidence of prolonged extubation achieved by desflurane, approximately 65% and 78%, respectively. These estimates give realistic context for interpretation of results of future studies that compare new anesthetic agents to current anesthetics.

Delirium Prevention and Management in Frail Surgical Patients

Delirium, an acute, fluctuating impairment in cognition and awareness, is one of the most common causes of postoperative brain dysfunction. It is associated with increased hospital length of stay, health care costs, and mortality. There is no FDA-approved treatment of delirium, and management relies on symptomatic control. Several preventative techniques have been proposed, including the choice of anesthetic agent, preoperative testing, and intraoperative monitoring. Frailty, a state of increased vulnerability to adverse events, is an independent and potentially modifiable risk factor for the development of delirium. Diligent preoperative screening techniques and implementation of prevention strategies could help improve outcomes in high-risk patients.

Neurosurgical Anesthesia: Optimizing Outcomes with Agent Selection

Anesthesia in neurosurgery embodies a vital element in the development of neurosurgical intervention. This undisputed interest has offered surgeons and anesthesiologists an array of anesthetic selections to utilize, though with this allowance comes the equally essential requirement of implementing a maximally appropriate agent. To date, there remains a lack of consensus and official guidance on optimizing anesthetic choice based on operating priorities including hemodynamic parameters (e.g., CPP, ICP, MAP) in addition to the route of procedure and pathology. In this review, the authors detail the development of neuroanesthesia, summarize the advantages and drawbacks of various anesthetic classes and agents, while lastly cohesively organizing the current literature of randomized trials on neuroanesthesia across various procedures.

Brain relaxation using desflurane anesthesia and total intravenous anesthesia in patients undergoing craniotomy for supratentorial tumors: a randomized controlled study

BACKGROUND

Satisfactory brain relaxation is essential in neurosurgery. Desflurane anesthesia and propofol-based total intravenous anesthesia (TIVA) have different effects on cerebral hemodynamics, potentially contributing to discrepant brain relaxation. The purpose of this study was to compare the effects of desflurane and TIVA on brain relaxation in patients undergoing craniotomy for supratentorial tumors.

METHODS

In this randomized, controlled study, we enrolled patients aged 18-60 years, with ASA I-III, who were scheduled to undergo elective craniotomy for supratentorial tumors. Patients were randomly assigned in a 1:1 ratio to receive desflurane anesthesia or TIVA. The primary outcome was the proportion of satisfactory brain relaxation. Secondary outcomes included emergence and extubation times, recovery of cognitive function and postoperative complications.

RESULTS

Of 369 patients who were assessed for eligibility, 111 were randomized and 110 were included in the modified intention-to-treat analysis (55 in the desflurane group and 55 in the TIVA group). The proportion of satisfactory brain relaxation was similar between the two groups: 69% in the desflurane group and 73% in the TIVA group (RR: 0.950, 95% CI: 0.748-1.207; P = 0.675). Patients assigned to the desflurane group had shorter emergence (10 [8-13] min vs. 13 [10-20] min, P < 0.001) and extubation times (13 [10-18] min vs. 17 [13-23] min, P < 0.001), and better recovery of cognitive function at 15 min after extubation (16 [0-24] vs. 0 [0-20], P = 0.003), but experienced increased postoperative nausea and vomiting (PONV) (16 [29%] vs. 6 [11%] P = 0.017) and tachycardia (22 [40%] vs. 9 [16%], P = 0.006) during recovery.

CONCLUSIONS

Desflurane anesthesia and TIVA provide similar brain relaxation in patients without intracranial hypertension undergoing elective craniotomy. Desflurane accelerates the recovery from anesthesia but is associated with increased PONV and tachycardia during the recovery period.

TRIAL REGISTRATION

Clinicaltrial.gov (NCT04691128). Date of registration: December 31, 2020.

A prospective observational single center study evaluating emergence agitation in the early postoperative period in adult patients undergoing elective craniotomies under general anesthesia

Background and Aims

Emergence agitation is a significant clinical issue during recovery from general anesthesia. Patients after intracranial operations are even more vulnerable to the stress resulting from emergence agitation. Due to the limited data available in neurosurgical patients, we evaluated the incidence, risk factors, and complications of emergence agitation.

Material and Methods

317 consenting eligible patients undergoing elective craniotomies were recruited. The preoperative Glasgow Coma Scale (GCS)) and pain score were recorded. Bispectral Index (BIS) guided balanced general anesthesia was administered and reversed. Immediate postoperatively, the GCS and the pain score were noted. The patients were observed for 24 hours following extubation. The levels of agitation and sedation were evaluated by the Riker's Agitation-Sedation Scale. Emergence Agitation was defined as Riker's Agitation score of 5 to 7.

Results

In our subset of the patient population, the incidence was 5.4%, mildly agitated in the first 24 hours and none required sedative medication as therapy. The sole risk factor identified was prolonged surgery beyond 4 hours. None of the patients in the agitated group had any complications.

Conclusion

Early objective assessment of risk factors in the preoperative period with objective validated tests and shorter duration of surgery maybe the way forward in patients at high risk for emergence agitation, to reduce the incidence and mitigate the undesirable consequences.

Comparison of the Occurrence of Postoperative Shivering Between Sevoflurane and Desflurane Anesthesia

General anesthetic agents can change the shivering threshold. Sevoflurane and desflurane are widely used as inhalational anesthetics and have also been reported to lower the shivering threshold in a dose-dependent manner. Although the comparison of postoperative shivering (POS) between total intravenous anesthesia and inhalational anesthesia has been reported, there have been no reports on a direct comparison between sevoflurane and desflurane anesthesia and the occurrence of POS in open abdominal surgery. After obtaining approval from the Ethics Review Committee (2020-261), 683 adult patients who underwent open radical surgery for uterine, cervical, or pancreatic cancer under general anesthesia using inhalational anesthetics at Kyushu University hospital between December 2012 and March 2020 were included in this retrospective study. The odds ratio (OR) for the occurrence of POS between the two groups (sevoflurane and desflurane) was calculated. Multivariable-adjusted analysis was performed using possible factors affecting POS. Furthermore, propensity score (PS) matching was conducted using these factors. The multivariable-adjusted OR for the occurrence of shivering in the desflurane group (62 occurrences/356 patients) was 1.06 (95% confidence interval [CI]: 0.69-1.62, p = 0.79) compared with the sevoflurane group (77/327, reference). Similarly, after PS matching, the crude OR for the occurrence of shivering in the desflurane group (47/210) was 1.09 (95% CI: 0.68-1.75, p = 0.72) compared with the sevoflurane group (44/210, reference). Similar results were obtained in the stratified analysis by sex and age. The occurrence of POS is not different between sevoflurane and desflurane anesthesia.

Effect of add-on Gabapentin premedication on hemodynamic response to skull pin insertion

Background and Aims:

Material and Methods:

Results:

Conclusion:

Role of anaesthesia in neurosurgical enhanced recovery programmes

The application of Enhanced Recovery After Surgery (ERAS) in neurosurgical practice is a relatively new concept. A limited number of studies involving ERAS protocols within neurosurgery, specifically for elective craniotomy, have been published, contrary to the ERAS spine surgery pathways that are now promoted by numerous national and international dedicated surgical societies and hospitals. In this review, we want to present the patient surgical journey from an anaesthesia perspective through the key components that can be included in the ERAS pathways for neurosurgical procedures, both craniotomies and major spine surgery.

Inhaled anesthesia in neurosurgery: Still a role?

In patients undergoing craniotomy, general anesthesia should be addressed to warrant good hypnosis, immobility, and analgesia, to ensure systemic and cerebral physiological status and provide the best possible surgical field. Regarding craniotomies, it is unclear if there are substantial differences in providing general anesthesia using total intravenous anesthesia (TIVA) or balanced anesthesia (BA) accomplished using the third generation halogenates. New evidence highlighted that the last generation of halogenated agents has possible advantages compared with intravenous drugs: rapid induction, minimal absorption and metabolization, reproducible pharmacokinetic, faster recovery, cardioprotective effect, and opioid spare analgesia. This review aims to report evidence related to the use of the latest halogenated agents in patients undergoing craniotomy and to present available clinical evidence on their effects: cerebral and systemic hemodynamic, neurophysiological monitoring, and timing and quality of recovery after anesthesia.

A Comparative Evaluation of the Effect of Prone Positioning Methods on Blood Loss and Intra-Abdominal Pressure in Obese Patients Undergoing Spinal Surgery

Background Improper prone positioning of obese patients for spine surgery can increase the intra-abdominal pressure (IAP), resulting in increased bleeding from epidural venous plexus. The choice of prone positioning frame can be an important determinant of the IAP.

Materials and Methods This prospective, randomized study was performed on obese patients (body mass index ≥ 30) scheduled for lumbar laminectomy. After administration of general anesthesia, patients were positioned prone either on Wilson’s frame (group W), or on horizontal bolsters (group H). IAP was recorded at three intervals: (1) in supine position, (2) 10 minutes after prone positioning, and (3) in prone position at the end of surgery. Intraoperative blood loss was measured quantitatively and assessed subjectively by the surgeon.

Results A total of 60 patients were enrolled with 30 patients in each group. IAP in supine position was similar in both groups. However, IAP 10 minutes after prone positioning was significantly higher at 11.44 ± 1.61 mm Hg in group W as compared to 9.56 ± 1.92 mm Hg in group H (p = 0.001). Similarly, IAP of 12.24 ± 1.45 mm Hg in group W, measured on completion of surgery was significantly higher than 9.96 ± 2.35 mm Hg in group H (p = 0.001). Mean total blood loss of 440.40 ± 176.98 mL in group W was significantly higher than 317.20 ± 91.04 mL in group H (p = 0.003).

Conclusion Obese patients positioned prone on Wilson’s frame had significantly higher IAP and blood loss compared to patients positioned on horizontal bolsters.

American Society for Enhanced Recovery and Perioperative Quality Initiative Joint Consensus Statement on Postoperative Delirium Prevention

Postoperative delirium is a geriatric syndrome that manifests as changes in cognition, attention, and levels of consciousness after surgery. It occurs in up to 50% of patients after major surgery and is associated with adverse outcomes, including increased hospital length of stay, higher cost of care, higher rates of institutionalization after discharge, and higher rates of readmission. Furthermore, it is associated with functional decline and cognitive impairments after surgery. As the age and medical complexity of our surgical population increases, practitioners need the skills to identify and prevent delirium in this high-risk population. Because delirium is a common and consequential postoperative complication, there has been an abundance of recent research focused on delirium, conducted by clinicians from a variety of specialties. There have also been several reviews and recommendation statements; however, these have not been based on robust evidence. The Sixth Perioperative Quality Initiative (POQI-6) consensus conference brought together a team of multidisciplinary experts to formally survey and evaluate the literature on postoperative delirium prevention and provide evidence-based recommendations using an iterative Delphi process and Grading of Recommendations Assessment, Development and Evaluation (GRADE) Criteria for evaluating biomedical literature.

DNA damage effects of inhalation anesthetics in human bronchoalveolar cells

BACKGROUND

The main objective was to evaluate and compare the local genotoxicity of sevoflurane and desflurane in bronchoalveolar cells, while the secondary outcome was to detect systemic oxidative DNA damage. To our knowledge, our study is the first one to evaluate the local effects of inhalation anesthetics in human bronchoalveolar cells in patients.

METHODS

American Society of Anesthesiologists group I-II patients scheduled for lumbar discectomy surgery were enrolled in this randomized prospective study. Patients were randomized to sevoflurane or desflurane for anesthesia maintenance. Bronchoalveolar lavage samples and peripheral blood samples were taken at 2-time points: the first point (baseline, T1); and the second point (postexposure, T2). Final number of 48 samples were the sevoflurane (n = 22) and desflurane (n = 26) groups. Comet assay was applied to examine genotoxic properties. Oxidative DNA damage in plasma was measured with 8-hydroxy-2'-deoxyguanosine (8-OHdG).

RESULTS

T2 values were higher than baseline values in both the desflurane group (tail-length: 66 ± 24, %DNA in tail: 72 ± 60, tail moment: 47.52 ± 14.4; P = .001, P = .005, P = .001, respectively) and the sevoflurane group (tail-length: 58 ± 33, %DNA in tail: 88 ± 80, tail moment: 51.04 ± 26.4; P = .001, P = .012, P = .001, respectively). T2 plasma 8-OHdG levels were also higher than baseline levels in the desflurane group (3.91 ± 0.19 ng/ml vs 1.32 ± 0.20 ng/ml, P = .001) and sevoflurane group (3.98 ± 0.18 ng/ml vs 1.31 ± 0.11 ng/ml, P = .001). There were no differences between the 2 groups in comet parameters and 8-OHdG levels.

CONCLUSION

Our results indicate that both inhalation agents cause DNA damage in the bronchoalveolar cells. Also, we detected increases in plasma 8-OHdG concentrations. Local genotoxicity and systemic oxidized DNA damage were similar in both groups.

A prospective randomized double-blind study to compare the early recovery profiles of desflurane and sevoflurane in patients undergoing laparoscopic cholecystectomy

Background and Aims

General anesthesia using agents like Desflurane or Sevoflurane are beneficial for early recovery especially for ambulatory procedures. The aim of this randomised controlled double-blind study was to compare the early recovery profiles of sevoflurane and desflurane in patients undergoing laparoscopic cholecystectomy.

Material and Methods

ASA I, II patients, undergoing laparoscopic cholecystectomy were randomly assigned to receive desflurane (n = 30) or sevoflurane (n = 30), using Bispectral Index System (BIS) to determine the depth of anaesthesia. An independent adjudicator, who was blinded to the agent used, recorded the events during the recovery phase. The time required for extubation, eye opening, verbal response and achievement of a modified Aldrete score of 9 were recorded.

Results

The time required for extubation and for eye opening was significantly shorter in the Desflurane group as compared to the Sevoflurane group [9.1 min ± 5.0 versus 12.5 min ± 7.1, P = 0.049 and 10.1 min ± 5.2 versus 6.3 min ± 4.0, P = 0.008]. Verbal Response also occurred significantly faster in the Desflurane group [12.7 min ± 5.4 versus 8.7 min ± 4.7, P = 0.002]. A significantly higher mean modified Aldrete score was seen at extubation [7.1 ± 0.6 vs 6.0 ± 0.8, P < 0.001] in the Desflurane group, which also achieved a modified Aldrete score of ≥9 significantly sooner [11.1 min ± 4.6 versus 17.8 min ± 6.9, P < 0.001] than the Sevoflurane group. The frequency of adverse effects was not significantly different in either of the groups.

Conclusion

The time required for early recovery from anaesthesia, was significantly shorter in the Desflurane group compared to the Sevoflurane group.

Effect of a low-dose dexmedetomidine infusion on intraoperative hemodynamics, anesthetic requirements and recovery profile in patients undergoing lumbar spine surgery

Background and Aims

Dexmedetomidine has been used as an anesthetic adjuvant; however, hypotension is a concern especially in prone patients. The aim of the study was to evaluate the effect of a low-dose dexmedetomidine infusion on intraoperative hemodynamics, blood loss, anesthetic requirements, and recovery profile in patients undergoing lumbar spine surgery in the prone position.

Material and Methods

The study was conducted in a randomized double-blinded manner in 60 patients scheduled for one- or two-level lumbar laminectomy. After administration of general anesthesia, patients were placed in prone position and allocated to either of two groups of 30 patients each. Patients in Group A received dexmedetomidine infusion at the rate of 0.3 μg kg^-1 hr^-1, whereas, group B patients received a saline infusion. The depth of anesthesia was guided by Bispectral index (BIS) monitoring, maintaining BIS between 40 and 60.

Results

The demographic profile and duration of surgery in both groups were similar. Mean heart rate was statistically similar in both the groups. Mean blood pressure was lower in group A, though the difference was significant only for the initial 30 min. The mean end-tidal sevoflurane requirement in group A was significantly less than that in group B (P = 0.003). Patients in group A had better recovery profile with mean emergence, extubation, and recovery times of 8.08 ± 3.48 min, 9.37 ± 3.64 min, and 11.65 ± 4.03 min, respectively, as compared with 11.27 ± 3.05 min, 12.24 ± 2.39 min, and 14.90 ± 2.63 min, respectively, in group B (P < 0.001). Mean intraoperative blood loss in group A of 263.47 ± 58.66 mL was significantly lower than 347.67 ± 72.90 ml in group B (P = 0.0001).

Conclusion

Group A patients had stable hemodynamic parameters, reduced intraoperative blood loss, less anesthetic requirement, and could be extubated earlier as compared with group B patients.

Cerebrovascular reactivity to hypercapnia during sevoflurane or desflurane anesthesia in rats

Background

Hypercapnia causes dilation of cerebral vessels and increases cerebral blood flow, resulting in increased intracranial pressure. Sevoflurane is reported to preserve cerebrovascular carbon dioxide reactivity. However, the contribution of inhaled anesthetics to vasodilatory responses to hypercapnia has not been clarified. Moreover, the cerebrovascular response to desflurane under hypercapnia has not been reported. We examined the effects of sevoflurane and desflurane on vasodilatory responses to hypercapnia in rats.

Methods

A closed cranial window preparation was used to measure the changes in pial vessel diameters. To evaluate the cerebrovascular response to hypercapnia and/or inhaled anesthetics, the pial vessel diameters were measured in the following states: without inhaled anesthetics at normocapnia (control values) and hypercapnia, with inhaled end-tidal minimal alveolar concentration (MAC) of 0.5 or 1.0 of either sevoflurane or desflurane at normocapnia, and an MAC of 1.0 of sevoflurane or desflurane at hypercapnia.

Results

Under normocapnia, 1.0 MAC, but not 0.5 MAC, of sevoflurane or desflurane dilated the pial arterioles and venules. In addition, under both 1.0 MAC of sevoflurane and 1.0 MAC of desflurane, hypercapnia significantly dilated the pial arterioles and venules in comparison to their diameters without inhaled anesthetics. The degrees of vasodilation were similar for desflurane and sevoflurane under both normocapnia and hypercapnia.

Conclusions

Desflurane induces cerebrovascular responses similar to those of sevoflurane. Desflurane can be used as safely as sevoflurane in neurosurgical anesthesia.

A prospective observational study of the use of desflurane anesthesia in Indian adult inpatients undergoing surgery: The Registry in India on Suprane Emergence registry

Background and Aims:

Limited registry studies are available on the use of anesthetic agents. This registry was conducted to evaluate emergence outcomes in Indian adult patients undergoing surgery with desflurane anesthesia.

Material and Methods:

This multicenter, prospective, non-interventional, observational study (Registry in India on Suprane Emergence [RISE] registry) included adult inpatients who received desflurane as general anesthetic for surgical procedure of ≥2 h. Patients were stratified by age into three groups: ≥18–40 years, ≥41–65 years, and >65 years. Data on patients’ demographics, practice, and usage pattern of medications were collected. The primary efficacy outcomes were time to extubation, time to response to verbal command, and time to orientation.

Results:

Of 236 patients screened, 201 (≥18–40 years, n = 70; ≥41–65 years, n = 65; >65 years, n = 66) were enrolled in the study. Mean time to extubation observed in ≥18–40 years group was 7.2 ± 4.1 min, ≥41–65 years was 11.6 ± 8.99 min, and >65 years was 12.0 ± 10.5 min. Mean time to response to verbal command was 7.4 ± 4.3 min for ≥18–40 years, 10.9 ± 8.5 min for ≥41–65 years, and 10.0 ± 5.4 min for >65 years. Mean time to orientation was 13.0 ± 7.0 min for ≥18–40 years, 16.1 ± 12.0 min for ≥41–65 years, and 17.0 ± 8.6 min for >65 years. Incidence of nausea and retching/vomiting was observed in 8% of patients each in the postoperative period, and these complications were seen more in the >65 years age group. Overall, desflurane treatment maintained hemodynamic stability and no major airway events were reported.

Conclusions:

The RISE registry data suggest that desflurane-based anesthesia provides early recovery with stable hemodynamics without any airway adverse events, in a wide variety of surgical procedures.

A clinical review of inhalation anesthesia with sevoflurane: from early research to emerging topics

A large number of studies during the past two decades have demonstrated the efficacy and safety of sevoflurane across patient populations. Clinical researchers have also investigated the effects of sevoflurane, its hemodynamic characteristics, its potential protective effects on several organ systems, and the incidence of delirium and cognitive deficiency. This review examines the clinical profiles of sevoflurane and other anesthetic agents, and focuses upon emerging topics such as organ protection, postoperative cognitive deficiency and delirium, and novel ways to improve postanesthesia outcomes.

Effects of avoiding neuromuscular blocking agents during maintenance of anaesthesia on recovery characteristics in patients undergoing craniotomy for supratentorial lesions: A randomised controlled study

Background and Aims:

Neuromuscular blocking agents have been one of the cornerstones of anaesthesia. With the advent of newer surgical, anaesthetic and neurological monitoring techniques, their utility in neuroanaesthesia practice seems dispensable. The aim of this prospective, comparative, randomised study was to determine whether neuromuscular blocking agents are required in patients undergoing supratentorial surgery when balanced anaesthesia with desflurane, dexmedetomidine and scalp block is used.

Methods:

Sixty patients with the American Society of Anesthesiologists physical status I or II, aged between 18 and 60 years were included in the study. All patients received anaesthesia including desflurane, dexmedetomidine and scalp block. The patients were randomly allocated to receive no neuromuscular blocking agent (Group A) or atracurium infusion to keep train-of-four count 2 (Group B). The two groups were compared with respect to haemodynamic stability, brain relaxation scores and recovery characteristics. Haemodynamic parameters and time taken to achieve Aldrete score >9 and other secondary outcomes were analysed using Student's t-test. Non-parametric data were analysed using the Mann–Whitney test.

Results:

The mean arterial pressure was comparable between the groups. The intraoperative heart rate was comparable; however, in the post-operative period, it remained higher in Group B for 30 min after extubation (P = 0.02). The brain relaxation scores were comparable among the two groups (P = 0.27). Tracheal extubation time, time taken for orientation and time required to reach Aldrete score ≥9 were comparable among the two groups.

Conclusion:

The present study suggests that balanced anaesthesia using desflurane, dexmedetomidine and scalp block can preclude the use of neuromuscular blocking agents in patients undergoing supratentorial surgery under intense haemodynamic monitoring.

The implantation effect: delay in seizure occurrence with implantation of intracranial electrodes

OBJECTIVE

A transient decrease in seizure frequency has been identified during therapeutic brain stimulation trials with stimulator in patients in the inactive sham group. This study was performed to examine whether the implantation of intracranial electrodes decreases seizure occurrence and explores factors that may be associated.

METHODS

A retrospective review of 193 patients was performed, all evaluated with both scalp video EEG monitoring and intracranial EEG (iEEG) monitoring. Data about the number of seizures per day during the monitoring period, the number of days until the first seizure, anti-epileptic drugs (AEDs), pain medications, types of implanted electrodes, and anesthetic agents were reviewed. We conducted a repeated measure analysis for counted data using generalized estimating equations with a log-link function and adjustment for number of days and anti-epileptic medication load on the previous day to compare seizure frequencies between scalp and iEEG monitoring.

RESULTS

The time to the first seizure was significantly prolonged during iEEG monitoring as compared to scalp monitoring after correction for AED withdrawal (hazard ratio: 0.81, CI 0.69-0.96). During scalp video EEG monitoring, patients experienced an average of 1.09 seizures/day vs 1.27 seizures/day during iEEG monitoring (P=.066). There was no significant difference in seizure frequency in patients that received craniotomy vs burr holes only for intracranial implantation. An increasing number of electrodes implanted increased the delay to seizures (P=.01). Of all anesthetic agents used, desflurane seemed to have an anticonvulsive effect compared to other anesthetics (P=.006). Pain medication did not influence delay to seizures.

SIGNIFICANCE

Seizures are delayed during iEEG as opposed to scalp monitoring illustrating the "implantation effect" previously observed. Surgical planning should account for longer monitoring periods, particularly when using larger intracranial arrays.

Anaesthetic interventions for prevention of awareness during surgery

BACKGROUND

General anaesthesia is usually associated with unconsciousness. 'Awareness' is when patients have postoperative recall of events or experiences during surgery. 'Wakefulness' is when patients become conscious during surgery, but have no postoperative recollection of the period of consciousness.

OBJECTIVES

To evaluate the efficacy of two types of anaesthetic interventions in reducing clinically significant awareness:- anaesthetic drug regimens; and- intraoperative anaesthetic depth monitors.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, ISSUE 4 2016); PubMed from 1950 to April 2016; MEDLINE from 1950 to April 2016; and Embase from 1980 to April 2016. We contacted experts to identify additional studies. We performed a handsearch of the citations in the review. We did not search trial registries.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) of either anaesthetic regimens or anaesthetic depth monitors. We excluded volunteer studies, studies of patients prior to skin incision, intensive care unit studies, and studies that only randomized different word presentations for memory tests (not anaesthetic interventions).Anaesthetic drug regimens included studies of induction or maintenance, or both. Anaesthetic depth monitors included the Bispectral Index monitor, M-Entropy, Narcotrend monitor, cerebral function monitor, cerebral state monitor, patient state index, and lower oesophageal contractility monitor. The use of anaesthetic depth monitors allows the titration of anaesthetic drugs to maintain unconsciousness.

DATA COLLECTION AND ANALYSIS

At least two authors independently scanned abstracts, extracted data from the studies, and evaluated studies for risk of bias. We made attempts to contact all authors for additional clarification. We performed meta-analysis statistics in packages of the R language.

MAIN RESULTS

We included 160 studies with 54,109 enrolled participants; 53,713 participants started the studies and 50,034 completed the studies or data analysis (or both). We could not use 115 RCTs in meta-analytic comparisons because they had zero awareness events. We did not merge 27 of the remaining 45 studies because they had excessive clinical and methodological heterogeneity. We pooled the remaining 18 eligible RCTs in meta-analysis. There are 10 studies awaiting classification which we will process when we update the review.The meta-analyses included 18 trials with 36,034 participants. In the analysis of anaesthetic depth monitoring (either Bispectral Index or M-entropy) versus standard clinical and electronic monitoring, there were nine trials with 34,744 participants. The overall event rate was 0.5%. The effect favoured neither anaesthetic depth monitoring nor standard clinical and electronic monitoring, with little precision in the odds ratio (OR) estimate (OR 0.98, 95% confidence interval (CI) 0.59 to 1.62).In a five-study subset of Bispectral Index monitoring versus standard clinical and electronic monitoring, with 34,181 participants, 503 participants gave awareness reports to a blinded, expert panel who adjudicated or judged the outcome for each patient after reviewing the questionnaires: no awareness, possible awareness, or definite awareness. Experts judged 351 patient awareness reports to have no awareness, 87 to have possible awareness, and 65 to have definite awareness. The effect size favoured neither Bispectral Index monitoring nor standard clinical and electronic monitoring, with little precision in the OR estimate for the combination of definite and possible awareness (OR 0.96, 95% CI 0.35 to 2.65). The effect size favoured Bispectral Index monitoring for definite awareness, but with little precision in the OR estimate (OR 0.60, 95% CI 0.13 to 2.75).We performed three smaller meta-analyses of anaesthetic drugs. There were nine studies with 1290 participants. Wakefulness was reduced by ketamine and etomidate compared to thiopental. Wakefulness was more frequent than awareness. Benzodiazepines reduces awareness compared to thiopental, ketamine, and placebo., Also, higher doses of inhaled anaesthetics versus lower doses reduced the risk of awareness.We graded the quality of the evidence as low or very low in the 'Summary of findings' tables for the five comparisons.Most of the secondary outcomes in this review were not reported in the included RCTs.

AUTHORS' CONCLUSIONS

Anaesthetic depth monitors may have similar effects to standard clinical and electrical monitoring on the risk of awareness during surgery. In older studies comparing anaesthetics in a smaller portion of the patient sample, wakefulness occurred more frequently than awareness. Use of etomidate and ketamine lowered the risk of wakefulness compared to thiopental. Benzodiazepines compared to thiopental and ketamine, or higher doses of inhaled anaesthetics versus lower doses, reduced the risk of awareness.

Postoperative complications after craniotomy for brain tumor surgery

INTRODUCTION

After elective craniotomy for brain tumour surgery, patients are usually admitted to an intensive care unit (ICU) for monitoring. Our goal was to evaluate the incidence and timing of neurologic and non-neurologic postoperative complications after brain tumour surgery, to determine factors associated with neurologic events and to evaluate the timing and causes of ICU readmission.

PATIENTS AND METHODS

This prospective, observational and analytic study enrolled 188 patients admitted to the ICU after brain tumour surgery. All postoperative clinical events during the first 24hours were noted and classified. Readmission causes and timing were also analysed.

RESULTS

Twenty-one (11%) of the patients were kept sedated after surgery; the remaining 167 patients were studied. Thirty one percent of the patients presented at least one complication (25% with postoperative nausea and vomiting (PONV), 16% with neurologic complications). The occurrence of neurological complications was significantly associated with the absence of preoperative motor deficit and the presence of higher intraoperative bleeding. Seven patients (4%) were readmitted to the ICU after discharge; 43% (n=3) of them had a posterior fossa surgery.

CONCLUSION

Postoperative complications, especially PONV, are frequent after brain tumour surgery. Moreover, 16% of patients presented a neurological complication, probably justifying the ICU postoperative stay for early detection. The absence of preoperative motor deficit and intraoperative bleeding seems to predict postoperative neurologic complications. Finally, patients may present complications after ICU discharge, especially patients with fossa posterior surgery, suggesting that ICU hospitalization may be longer in this type of surgery.

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.

Effects of changing from sevoflurane to desflurane on the recovery profile after sevoflurane induction: a randomized controlled study

PURPOSE

Desflurane has the lowest solubility of currently available volatile anesthetics and may allow for more rapid emergence and recovery compared with sevoflurane. Nevertheless, after volatile induction with sevoflurane, it has not been determined whether the use of desflurane provides faster emergence and recovery. The present study aimed to elucidate the effects of changing from sevoflurane to desflurane during the early part of anesthesia.

METHODS

Fifty-two patients who were scheduled for vitreous surgery with general anesthesia were enrolled in this randomized controlled study. Anesthesia was induced with volatile induction consisting of 100% oxygen (6 L·min(-1)) and 5% sevoflurane. For anesthesia maintenance, patients were randomized to receive 1-2% sevoflurane or 3-6% desflurane. In the desflurane group, the anesthetic agent was changed from sevoflurane to desflurane within five minutes following endotracheal intubation. After surgery, we assessed the following endpoints: the times from discontinuing volatile anesthetics to eye opening, obeying the command to squeeze the investigator's hand, tracheal extubation, and orientation to the patients' full name, date, and place.

RESULTS

Emergence and recovery were significantly faster in the desflurane group than in the sevoflurane group in times to mean (SD) eye opening [6.5 (2.9) vs 10.1(3.0) min, respectively; mean difference, 3.6 min; 95% confidence interval (CI), 1.9 to 5.3; P < 0.001], obeying commands [6.6 (2.7) vs 10.1 (3.1) min, respectively; mean difference, 3.5 min; 95% CI, 1.9 to 5.2; P < 0.001], and tracheal extubation [7.0 (2.5) vs 10.6 (3.0) min, respectively; mean difference, 3.6 min; 95% CI, 1.9 to 5.1; P < 0.001]. Similarly, the times from discontinuation of volatile anesthetics to orientation to the patients' full name, date, and place were significantly shorter in the desflurane group compared with the sevoflurane group. There were no significant differences between groups on a 100-mm visual analogue scale assessing postoperative nausea and vomiting, eye pain, and patient satisfaction regarding anesthesia.

CONCLUSION

Changing the anesthetic agent from sevoflurane to desflurane after sevoflurane induction provides faster emergence and recovery compared with sevoflurane anesthesia. This study protocol was registered at http://www.umin.ac.jp/ctr/index.htm , (UMIN000009941).

Comparison between sevoflurane and desflurane on emergence and recovery characteristics of children undergoing surgery for spinal dysraphism

Background and Aims:

Rapid recovery is desirable after neurosurgery as it enables early post-operative neurological evaluation and prompt management of complications. Studies have been rare comparing the recovery characteristics in paediatric neurosurgical patients. Hence, this study was carried out to compare the effect of sevoflurane and desflurane anaesthesia on emergence and extubation in children undergoing spinal surgery.

Methods:

Sixty children, aged 1–12 years, undergoing elective surgery for lumbo-sacral spinal dysraphism were enrolled. Anaesthesia was induced with sevoflurane using a face mask. The children were then randomised to receive either sevoflurane or desflurane with oxygen and nitrous oxide, fentanyl (1 μg/kg/h) and rocuronium. The anaesthetic depth was guided by bispectral index (BIS^®) monitoring with a target BIS^® between 45 and 55. Perioperative data with regard to demographic profile, haemodynamics, emergence and extubation times, modified Aldrete score (MAS), pain (objective pain score), agitation (Cole's agitation score), time to first analgesic and complications, thereof, were recorded. Statistical analysis was done using STATA 11.2 (StataCorp., College Station, TX, USA) and data are presented as median (range) or mean ± standard deviation.

Results:

The demographic profile, haemodynamics, MAS, pain and agitation scores and time to first analgesic were comparable in between the two groups (P > 0.05). The emergence time was shorter in desflurane group (2.75 [0.85–12] min) as compared to sevoflurane (8 [2.5–14] min) (P < 0.0001). The extubation time was also shorter in desflurane group (3 [0.8–10] min) as compared to the sevoflurane group (5.5 [1.2–14] min) (P = 0.0003).

Conclusion:

Desflurane provided earlier tracheal extubation and emergence as compared to sevoflurane in children undergoing surgery for lumbo-sacral spinal dysraphism.

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.

Aneurysmal Subarachnoid Hemorrhage

Aneurysmal subarachnoid hemorrhage (SAH) is a worldwide health burden with high fatality and permanent disability rates. The overall prognosis depends on the volume of the initial bleed, rebleeding, and degree of delayed cerebral ischemia (DCI). Cardiac manifestations and neurogenic pulmonary edema indicate the severity of SAH. The International Subarachnoid Aneurysm Trial (ISAT) reported a favorable neurological outcome with the endovascular coiling procedure compared with surgical clipping at the end of 1 year. The ISAT trial recruits were primarily neurologically good grade patients with smaller anterior circulation aneurysms, and therefore the results cannot be reliably extrapolated to larger aneurysms, posterior circulation aneurysms, patients presenting with complex aneurysm morphology, and poor neurological grades. The role of hypothermia is not proven to be neuroprotective according to a large randomized controlled trial, Intraoperative Hypothermia for Aneurysms Surgery Trial (IHAST II), which recruited patients with good neurological grades. Patients in this trial were subjected to slow cooling and inadequate cooling time and were rewarmed rapidly. This methodology would have reduced the beneficial effects of hypothermia. Adenosine is found to be beneficial for transient induced hypotension in 2 retrospective analyses, without increasing the risk for cardiac and neurological morbidity. The neurological benefit of pharmacological neuroprotection and neuromonitoring is not proven in patients undergoing clipping of aneurysms. DCI is an important cause of morbidity and mortality following SAH, and the pathophysiology is likely multifactorial and not yet understood. At present, oral nimodipine has an established role in the management of DCI, along with maintenance of euvolemia and induced hypertension. Following SAH, hypernatremia, although less common than hyponatremia, is a predictor of poor neurological outcome.

Comparative evaluation of propofol, sevoflurane and desflurane for neuroanaesthesia: A prospective randomised study in patients undergoing elective supratentorial craniotomy

Background and Aims:

Both inhalational and intravenous anaesthetic agents are being used for neuroanaesthesia. Clinical trials comparing “propofol and sevoflurane” and “desflurane and sevoflurane” have been published. However, the comparison of all the three anaesthetics in neurosurgical patients has not been done. A randomised clinical study was carried out comparing propofol, sevoflurane and desflurane to find the ideal neuroanaesthetic agent.

Methods:

A total of 75 adult patients undergoing elective craniotomy for supratentorial tumours were included in the study. The patients were induced with morphine 0.1 mg/kg and thiopentone 4-6 mg/kg. Neuromuscular blockade was facilitated with vecuronium. The patients were randomised to receive propofol, sevoflurane or desflurane along with nitrous oxide in oxygen for maintenance of anaesthesia. The neuromuscular blockade was reversed following the surgery once the patients opened eyes or responded to verbal commands. The three anaesthetics were compared for their effects on haemodynamics, brain relaxation and emergence characteristics.

Results:

The mean arterial blood pressure during anaesthesia was comparable among the groups. The patients receiving sevoflurane had faster heart rates intraoperatively when compared to desflurane (P < 0.05). The brain relaxation scores at various intraoperative time frames were comparable among the three groups (P > 0.05). The time to response to verbal commands were significantly prolonged with use of sevoflurane (8.0 ± 2.9 min) when compared to propofol (5.3 ± 2.9 min) and desflurane (5.2 ± 2.6 min) (P = 0.003). However, the time to emergence and the number of patients who had early emergence (<15 min) were comparable among the groups (P > 0.05). The quality of emergence (coughing and emergence agitation), as well as postoperative complications, were also comparable among the three groups.

Conclusions:

All the three anaesthetic agents-propofol, sevoflurane and desflurane appear comparable and acceptable with regard to their clinical profile during anaesthesia in patients undergoing elective supratentorial surgeries.

Comparison of intraoperative brain condition, hemodynamics and postoperative recovery between desflurane and sevoflurane in patients undergoing supratentorial craniotomy

Background:

Post operative recovery has been reported to be faster with desflurane than sevoflurane anesthesia in previous studies. The use of desflurane is often criticized in neurosurgery due to the concerns of cerebral vasodilation and increase in ICP and studies comparing desflurane and sevoflurane in neurosurgey are scarce. So we compared the intraoperative brain condition, hemodynamics and postoperative recovery in patients undergoing elective supratentorial craniotomy receiving either desflurane or sevoflurane.

Materials and Methods:

Fifty three patients between 18-60yr undergoing elective supratentorial craniotomy receiving N₂O and oxygen (60%:40%) and 0.8-1.2 MAC of either desflurane or sevoflurane were randomized to group S (Sevoflurane) or group D (Desflurane). Subdural intra cranial pressure (ICP) was measured and brain condition was assessed.. Emergence time, tracheal extubation time and recovery time were recorded. Cognitive behavior was evaluated with Short Orientation Memory Concentration Test (SOMCT) and neurological outcome (at the time of discharge) was assessed using Glasgow Outcome Score (GOS) between the two groups.

Results:

The emergence time [Group D 7.4 ± 2.7 minutes vs. Group S 7.8 ± 3.7 minutes; P = 0.65], extubation time [Group D 11.8 ± 2.8 minutes vs. Group S 12.9 ± 4.9 minutes; P = 0.28] and recovery time [Group D 16.4 ± 2.6 minutes vs. Group S 17.1 ± 4.8 minutes; P = 0.50] were comparable between the two groups. There was no difference in ICP [Group D; 9.1 ± 4.3 mmHg vs. Group S; 10.9 ± 4.2 mmHg; P = 0.14] and brain condition between the two groups. Both groups had similar post-operative complications, hospital and ICU stay and GOS.

Conclusion:

In patients undergoing elective supratentorial craniotomy both sevoflurane and desflurane had similar intra-operative brain condition, hemodynamics and post operative recovery profile.

Recovery of postoperative cognitive function in elderly patients after a long duration of desflurane anesthesia: a pilot study

Postoperative cognitive dysfunction (POCD) increases morbidity and mortality. The mechanisms underlying POCD remain elusive; however, systemic responses induced by anesthesia and surgery might trigger neuroinflammation and POCD. Desflurane is a preferable volatile anesthetic agent for elderly patients because it facilitates shorter recovery from general anesthesia. The aim of this study was to determine whether quality of emergence and cognitive function in elderly patients undergoing a long duration desflurane anesthesia are better than those in the case of sevoflurane anesthesia. Forty-two patients who were older than 65 years of age and scheduled for surgery of more than 4 h in duration were enrolled in this study. Patients were randomly assigned to a desflurane anesthesia group (D group) and sevoflurane anesthesia group (S group). General anesthesia was maintained with 3.5 % desflurane (D group) and 1.0 % sevoflurane (S group). The Mini-Mental State Examination (MMSE) was used for assessing cognitive function 24 h before and after surgery. Postoperative MMSE score in the D group was significantly improved compared to that in the preoperative period. In conclusion, elderly patients undergoing desflurane anesthesia have significantly better quality of emergence and may have better cognitive function than those in elderly patients undergoing sevoflurane anesthesia.

Remote cerebellar hemorrhage after unruptured cerebral aneurysm surgery: two cases report

Remote cerebellar hemorrhage (RCH) occurring distant to the site of original surgery, such as supratentorial or spinal surgery, is rare but potentially fatal. Because the pathophysiology of RCH is thought to be excessive cerebrospinal fluid drainage during the perioperative periods, its diagnosis usually depends on the occurrence of unexpected neurologic disturbances and/or postoperative brain computerized tomography imaging. Because of its rarity, RCH-associated neurologic disturbances such as delayed awakening or nausea and vomiting may often be misdiagnosed as the effects of residual anesthetics or the effect of postoperative analgesic agents unless radiologic images are taken. Treatment for RCH ranges from conservative treatment to decompressive craniectomy, with prognoses ranging from complete resolution to fatality. Here, we report two cases of RCH after surgical clipping of an unruptured cerebral aneurysm of the anterior communicating artery and review anesthetic considerations.

A comparison of 1 minimum alveolar concentration desflurane and 1 minimum alveolar concentration isoflurane anesthesia in patients undergoing craniotomy for supratentorial lesions

BACKGROUND

A critical point in craniotomy is during opening of the dura and the subsequent potential for cerebral edema. Use of desflurane in neurosurgery may be beneficial because it facilitates early postoperative neurologic evaluation; however, data on the effect of desflurane on intracranial pressure in humans are limited. Isoflurane has been used extensively in neurosurgical patients.

OBJECTIVE

This study compared 1 minimum alveolar concentration (MAC) desflurane with 1 MAC isoflurane in facilitating hemodynamic stability, brain relaxation, and postoperative recovery characteristics in patients who underwent craniotomy for supratentorial lesions.

METHODS

A total of 70 patients (aged 18-65 years), with American Society of Anesthesiologists (ASA) 1 or 2 physical status, who underwent craniotomy for supratentorial lesions, were enrolled in the study. For induction of anesthesia, fentanyl (2 μg/kg IV) and propofol (2 mg/kg IV) were administered. Endotracheal intubation was performed after administration of vecuronium (0.1 mg/kg IV) for total muscle relaxation. Before insertion of the skull pins, additional fentanyl (2 μg/kg IV) was administered. Patients were randomly allocated to 1 of 2 anesthetic regimens. For maintenance of anesthesia, 35 patients received 1 MAC of desflurane (group 1) and 35 patients received 1 MAC of isoflurane (group 2) within 50% oxygen in nitrous oxide. Intraoperatively, heart rate (HR) and mean arterial pressure (MAP) were measured and recorded before induction and 1 minute after induction, after endotracheal intubation, before skull pin insertion and 1 minute after skull pin insertion, before incision and 1 minute after incision, and before extubation and 1 minute after extubation. Also, HR and MAP were recorded at 30-minute intervals. Postoperatively, extubation time, eye opening time to verbal stimuli, orientation time, and time to reach an Aldrete postanesthetic recovery score of ≥8 were recorded. In addition, opioid consumption was calculated and recorded. Brain relaxation was evaluated according to a 4-step brain relaxation scoring scale. All outcomes of the study were assessed and recorded by an anesthesiologist blinded to the volatile anesthetic gases studied.

RESULTS

No significant difference in HR was observed between the 2 groups. Intraoperative MAP values in group 1 were higher than in group 2 (P < 0.05). No significant difference was found between these groups in brain relaxation and opioid consumption. Extubation time, eye opening time to verbal stimuli, and time to reach an Aldrete score of ≥8 were found to be significantly shorter in patients in group 1 compared with patients in group 2 (P < 0.05).

CONCLUSIONS

In patients who underwent craniotomy for supratentorial lesions, patients who received 1 MAC desflurane-based anesthesia had earlier postoperative cognitive recovery and postoperative neurologic examination compared with patients who received 1 MAC isoflurane-based anesthesia. The observed benefits of early recovery from anesthesia, however, should be considered with risks such as higher MAP in patients administered 1 MAC desflurane.

Research studies that have influenced practice of neuroanesthesiology in recent years: A literature review

Through evolving research, recent years have witnessed remarkable achievements in neuromonitoring and neuroanesthetic techniques, with a huge body of literature consisting of excellent studies in neuroanaesthesiology. However, little of this work appears to be directly important to clinical practice. Many controversies still exist in care of patients with neurologic injury. This review discusses studies of great clinical importance carried out in the last five years, which have the potential of influencing our current clinical practice and also attempts to define areas in need of further research. Relevant literature was obtained through multiple sources that included professional websites, medical journals and textbooks using key words “neuroanaesthesiology,” “traumatic brain injury,” “aneurysmal subarachnoid haemorrhage,” “carotid artery disease,” “brain protection,” “glycemic management” and “neurocritical care.” In head injured patients, administration of colloid and pre-hospital hypertonic saline resuscitation have not been found beneficial while use of multimodality monitoring, individualized optimal cerebral perfusion pressure therapy, tranexamic acid and decompressive craniectomy needs further evaluation. Studies are underway for establishing cerebroprotective potential of therapeutic hypothermia. Local anaesthesia provides better neurocognitive outcome in patients undergoing carotid endarterectomy compared with general anaesthesia. In patients with aneurysmal subarachnoid haemorrhage, induced hypertension alone is currently recommended for treating suspected cerebral vasospasm in place of triple H therapy. Till date, nimodipine is the only drug with proven efficacy in preventing cerebral vasospasm. In neurocritically ill patients, intensive insulin therapy results in substantial increase in hypoglycemic episodes and mortality rate, with current emphasis on minimizing glucose variability. Results of ongoing multicentric trials are likely to further improvise our practice.

Bispectral index and their relation with consciousness of the patients who receive desflurane or sevoflurane anesthesia during wake-up test for spinal surgery for correction

BACKGROUND

Wake-up tests may be necessary during surgery for kypho-scoliosis to ensure that spinal function remains intact. It is difficult to predict the time when patients can respond to a verbal command. We evaluated the effectiveness of the bispectral index (BIS) and its relation to patients' levels of consciousness in wake-up tests during desflurane and sevoflurane anesthesia.

METHODS

Eighteen patients each were enrolled in the desflurane and sevoflurane groups for spinal correction surgery. We measured BIS values, blood pressure, heart rate, and consciousness state and time, at the points when patients responded during the wake-up test.

RESULTS

The BIS values when patients made fists upon a verbal command (T3) were 86.7 ± 7.5 for desflurane and 90.3 ± 5.4 for sevoflurane. Patients in the desflurane group had significantly shorter wake up delays than those in the sevoflurane group (6.9 ± 1.8 min vs. 11.8 ± 3.6 min). However, there was no difference between the groups in the time between the response to a verbal command and the time when a patient moved their toes in response to verbal commands. No recall of the wake-up tests occurred in either group.

CONCLUSIONS

The values obtained using the BIS index could to some extent predict the time of a patient's and would be informative during desflurane and sevoflurane anesthesia. Moreover, desflurane permitted faster responses to verbal commands than sevoflurane, and allowed the wake-up test to be performed sooner.

Desflurane - revisited

The search for an ideal inhalational general anesthetic agent continues. Desflurane, which was recently introduced in the Indian market, possesses favorable pharmacokinetic and pharmacodynamic properties and is closer to the definition of an ideal agent. It offers the advantage of precise control over depth of anesthesia along with a rapid, predictable, and clear-headed recovery with minimal postoperative sequelae, making it a valuable anesthetic agent for maintenance in adults and pediatric patients in surgeries of all durations. The agent has advantages when used in extremes of age and in the obese. Its use may increase the direct costs of providing anesthetic care. Methods or techniques, such as low-flow anesthesia, to reduce the overall cost and along with minimal environmental implications must be followed.