Esmolol blunts postoperative hemodynamic changes after propofol-remifentanil total intravenous fast-track neuroanesthesia for intracranial surgery. J Clin Anesth. 2008;20:426-430. [PMID: 18929282 DOI: 10.1016/j.jclinane.2008.04.006]

Esmolol as an adjunct to general balanced anaesthesia in neurosurgery

Background/Aim: In surgery, and especially in the neurosurgical operations, maintenance of cardiovascular stability during and in the phase of the immediate postoperative recovery is of vital importance. The aim of this study was to investigate the effects of continuous esmolol infusion on the values of cardiovascular parameters and quality of the emergence from anaesthesia in neurosurgical patients. Methods: A total of 40 patients of both sexes scheduled for elective supratentorial surgery were randomly assigned to two groups. Esmolol group received intravenous (iv) infusion of esmolol dissolved in 5 % glucose solution (during the first 5 min at a rate of 0.3 mg/kg/min and thereafter at a rate of 0.1 mg/kg/min), while the ones from the control group received a 5 % glucose solution without esmolol at the same volume and rate. Cardiovascular parameters were registered at critical phases of anaesthesia and operation (induction, intubation, placement of Mayfield frame, craniotomy, skull closure, extubation). Recovery after anaesthesia was assessed based on times of eye opening on command, spontaneous eye opening and regaining of full orientation. Results: Values of systolic blood pressure and heart rate were significantly lower in the esmolol than in the control group of patients. Although the durations of anaesthesia did not differ, patients from the esmolol group required significantly less opioids and isoflurane and recovered after the anaesthesia significantly faster than the patients in the control group. Conclusion: Ultrashort-acting beta-adrenergic receptor antagonist esmolol, administered as a continuous iv infusion, assures better cardiovascular stability and smoother emergence from the balanced inhalation general anaesthesia than the control glucose infusion in elective neurosurgical patients.

Elevated blood pressure after craniotomy: A prospective observational study

PURPOSE

Close hemodynamic monitoring after craniotomy is routine given risk for post-operative hypertension, systemic and neurological complications. Patient and peri-operative variables associated with increased risk of post-craniotomy hypertension and complications are not well understood. Our analysis aims to estimate the incidence and prevalence of post-craniotomy hypertension, its time course, contributing factors, and post-craniotomy complications.

MATERIAL AND METHODS

This is a prospective study of patients admitted to the Neurosurgical Intensive Care Unit after an elective craniotomy. Variables associated with pre-surgical risk, demographics, and post-operative care were analyzed.

RESULTS

A total of 282 patients were included in the final analysis, 44% had pre-existing hypertension. Post-craniotomy hypertension was seen in 21%, with a higher incidence in patients with pre-existing hypertension (p < .001), smaller craniotomies (p = .0035), and increased use of analgesic medications (p < .001). History of hypertension was the only independent risk factor for post-craniotomy hypertension in a multivariate regression model. Patients who developed post-craniotomy hypertension, showed a significant increase in length of stay, number and duration of antihypertensive treatment. However, post-craniotomy hypertension was not associated with a higher incidence of other post-operative complications.

CONCLUSIONS

Development of hypertension after craniotomy is multi-factorial. In this prospective study, a prior history of hypertension was the only associated independent risk factor.

ProSeal Laryngeal Mask Airway Attenuates Systemic and Cerebral Hemodynamic Response During Awakening of Neurosurgical Patients: A Randomized Clinical Trial

BACKGROUND

Extubation and emergence from anesthesia may lead to systemic and cerebral hemodynamic changes that endanger neurosurgical patients. We aimed to compare systemic and cerebral hemodynamic variables and cough incidence in neurosurgery patients emerging from general anesthesia with the standard procedure (endotracheal tube [ETT] extubation) or after replacement of the ETT with a laryngeal mask airway (LMA).

MATERIALS AND METHODS

Forty-two patients undergoing supratentorial craniotomy under general anesthesia were included in a randomized open-label parallel trial. Patients were randomized (sealed envelopes labeled with software-generated randomized numbers) to awaken with the ETT in place or after its replacement with a ProSeal LMA. We recorded mean arterial pressure as the primary endpoint and heart rate, middle cerebral artery flow velocity, regional cerebral oxygen saturation, norepinephrine plasma concentrations, and coughing.

RESULTS

No differences were found between groups at baseline. All hemodynamic variables increased significantly from baseline in both groups during emergence. The ETT group had significantly higher mean arterial pressure (11.9 mm Hg; 95% confidence interval [CI], 2.1-21.8 mm Hg) (P=0.017), heart rate (7.2 beats/min; 95% CI, 0.7-13.7 beats/min) (P=0.03), and rate-pressure product (1045.4; 95% CI, 440.8-1650) (P=0.001). Antihypertensive medication was administered to more ETT-group patients than LMA-group patients (9 [42.9%] vs. 3 [14.3%] patients, respectively; P=0.04). The percent increase in regional cerebral oxygen saturation was greater in the ETT group by 26.1% (95% CI, 9.1%-43.2%) (P=0.002), but no between-group differences were found in MCA flow velocity. Norepinephrine plasma concentrations rose in both groups between baseline and the end of emergence: LMA: from 87.5±7.1 to 125.6±17.3 pg/mL; and ETT: from 118.1±14.1 to 158.1±24.7 pg/mL (P=0.007). The differences between groups were not significant. The incidence of cough was higher in the ETT group (87.5%) than in the LMA group (9.5%) (P<0.001).

CONCLUSIONS

Replacing the ETT with the LMA before neurosurgical patients emerge from anesthesia results in a more favorable hemodynamic profile, less cerebral hyperemia, and a lower incidence of cough.

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.

Short acting insulin analogues in intensive care unit patients

Blood glucose control in intensive care unit (ICU) patients, addressed to actively maintain blood glucose concentration within defined thresholds, is based on two major therapeutic interventions: to supply an adequate calories load and, when necessary, to continuously infuse insulin titrated to patients needs: intensive insulin therapy (IIT). Short acting insulin analogues (SAIA) have been synthesized to improve the chronic treatment of patients with diabetes but, because of the pharmacokinetic characteristics that include shorter on-set and off-set, they can be effectively used also in ICU patients and have the potential to be associated with a more limited risk of inducing episodes of iatrogenic hypoglycemia. Medical therapies carry an intrinsic risk for collateral effects; this can be more harmful in patients with unstable clinical conditions like ICU patients. To minimize these risks, the use of short acting drugs in ICU patients have gained a progressively larger room in ICU and now pharmaceutical companies and researchers design drugs dedicated to this subset of medical practice. In this article we report the rationale of using short acting drugs in ICU patients (i.e., sedation and treatment of arterial hypertension) and we also describe SAIA and their therapeutic use in ICU with the potential to minimize iatrogenic hypoglycemia related to IIT. The pharmacodynamic and pharmachokinetic characteristics of SAIA will be also discussed.

The effect of sufentanil administration on remifentanil-based anaesthesia during laparoscopic gynaecological surgery: a double-blind randomized controlled trial

This study assessed the effect of sufentanil administered before conclusion of remifentanil-based anaesthesia on postoperative hyperalgesia and haemodynamic stability in patients undergoing laparoscopic gynaecological surgery. The patients were randomly allocated to a sufentanil administration group (S group) or a normal saline administration group (C group). Anaesthesia was induced and maintained with controlled administration of remifentanil at 10 ng · mL(-1) and propofol under bispectral index guidance. Once the surgical specimen was procured, sufentanil or normal saline was administered at 0.15 ng · mL(-1) and maintained until extubation. The haemodynamic status during anaesthetic emergence was evaluated. The pain and postoperative nausea and vomiting (PONV) were assessed for 72 h following postanaesthetic care unit (PACU) discharge. The S group had significantly lower mean systemic arterial blood pressure and heart rate changes between the start of drug administration and extubation. Postoperative pain was significantly lower in the S group until 24 h following PACU discharge. There were no significant differences in PONV incidence and severity 72 h after PACU discharge between the two groups. Sufentanil administration before concluding remifentanil-based anaesthesia improved postoperative hyperalgesia and achieved haemodynamic stability at extubation without delaying recovery or increasing PONV during laparoscopic gynaecological surgery. Clinical trial registration is found at KCT0000785.

Cerebral hyperaemia after isoflurane anaesthesia for craniotomy of patients with supratentorial brain tumour

BACKGROUND

Few studies look into cerebral blood flow (CBF) changes during emergence from general anaesthesia for craniotomy. The purpose of this study was to assess CBF changes during emergence from general anaesthesia for craniotomy, through monitoring blood oxygen saturation of jugular vein bulb (SjvO2 ) and transcranial Doppler (TCD).

METHODS

We enrolled 30 patients undergoing selective craniotomy (group C) for supratentorial brain tumour resection and 30 patients undergoing selective abdominal surgery (group A). Mean velocity of middle cerebral artery (Vmca), mean arterial pressure (MAP), SjvO2 (only measured in group C), and arterial CO2 partial pressure were measured before anaesthesia, at tracheal extubation, and 30, 60, 90, 120 min after extubation.

RESULTS

Vmca of the same side of tumour was significantly higher than contralateral Vmca before anaesthesia and at all times after extubation in group C. The ipsilateral Vmca increased significantly (95.7 ± 16.9 cm/s vs. 63.7 ± 6.7 cm/s, P < 0.01) at extubation in group C, then declined but still above baseline significantly in the first 2 h after extubation. While Vmca of the right side changed only slightly (63.6 ± 7.7 cm/s vs. 61.8 ± 8.1 cm/s, P < 0.01) but significantly at extubation in group A. SjvO2 increased significantly (81.4% ± 7.4% vs. 60.9% ± 3.7%, P < 0.01) at extubation in group C, and remained above baseline significantly for 2 h. There was no significant correlation between Vmca and MAP at any time.

CONCLUSIONS

Cerebral hyperaemia occurs after supratentorial brain tumour resection surgery. The hyperaemia is more pronounced on the same side as the tumour.

Comparison of bolus and continuous infusion of esmolol on hemodynamic response to laryngoscopy, endotracheal intubation and sternotomy in coronary artery bypass graft

BACKGROUND AND OBJECTIVE

The aim of this randomized, prospective and double blinded study is to investigate effects of different esmolol use on hemodynamic response of laryngoscopy, endotracheal intubation and sternotomy in coronary artery bypass graft surgery.

METHODS

After approval of local ethics committee and patients' written informed consent, 45 patients were randomized into three groups equally. In Infusion Group; from 10 min before intubation up to 5th minute after sternotomy, 0.5mg/kg/min esmolol infusion, in Bolus Group; 2 min before intubation and sternotomy 1.5mg/kg esmolol IV bolus and in Control Group; %0.9 NaCl was administered. All demographic parameters were recorded. Heart rate and blood pressure were recorded before infusion up to anesthesia induction in every minute, during endotracheal intubation, every minute for 10 minutes after endotracheal intubation and before, during and after sternotomy at first and fifth minutes.

RESULTS

While area under curve (AUC) (SAP×time) was being found more in Group B and C than Group I, AUC (SAP×Tint and Tst) and AUC (SAP×T2) was found more in Group B and C than Group I (p<0.05). Moreover AUC (HR×Tst) was found less in Group B than Group C but no significant difference was found between Group B and Group I.

CONCLUSION

This study highlights that esmolol infusion is more effective than esmolol bolus administration on controlling systolic arterial pressure during endotracheal intubation and sternotomy in CABG surgery.

Training anesthesiology residents in providing anesthesia for awake craniotomy: learning curves and estimate of needed case load

STUDY OBJECTIVE

To measure the learning curves of residents in anesthesiology in providing anesthesia for awake craniotomy, and to estimate the case load needed to achieve a "good-excellent" level of competence.

DESIGN

Prospective study.

SETTING

Operating room of a university hospital.

SUBJECTS

7 volunteer residents in anesthesiology.

MEASUREMENTS

Residents underwent a dedicated training program of clinical characteristics of anesthesia for awake craniotomy. The program was divided into three tasks: local anesthesia, sedation-analgesia, and intraoperative hemodynamic management. The learning curve for each resident for each task was recorded over 10 procedures. Quantitative assessment of the individual's ability was based on the resident's self-assessment score and the attending anesthesiologist's judgment, and rated by modified 12 mm Likert scale, reported ability score visual analog scale (VAS). This ability VAS score ranged from 1 to 12 (ie, very poor, mild, moderate, sufficient, good, excellent). The number of requests for advice also was recorded (ie, resident requests for practical help and theoretical notions to accomplish the procedures).

MAIN RESULTS

Each task had a specific learning rate; the number of procedures necessary to achieve "good-excellent" ability with confidence, as determined by the recorded results, were 10 procedures for local anesthesia, 15 to 25 procedures for sedation-analgesia, and 20 to 30 procedures for intraoperative hemodynamic management.

CONCLUSIONS

Awake craniotomy is an approach used increasingly in neuroanesthesia. A dedicated training program based on learning specific tasks and building confidence with essential features provides "good-excellent" ability.

Esmolol: a unique Beta-blocker in maintaining cardiovascular stability following neurosurgical procedures

PURPOSE

Patients with increased intracranial pressure (ICP) are prone to severe cardiac and or cerebral complications following emergence from general anesthesia and especially post-extubation phase. Administering beta blockers including esmolol is believed to be helpful in providing a stable hemodynamic at the end of the surgery and recovery stages and reducing recovery phase length.

METHOD

In a double-blind prospective randomized clinical trial, 60 adult patients with ASA (American Society of Anesthesiologist) class of I-II scheduled to undergo elective neurosurgery operations were randomly divided into two groups receiving esmolol (n=30) and placebo (n=30) as IV infusion within four minutes prior to extubation continued by an IV infusion for 10 minutes after extubation.

RESULT

There was a significant difference between two groups regarding the changes of systolic blood pressure and heart rate at all studied stages after extubation (P≤0.05). However, no significant difference existed between esmolol and control groups regarding recovery and extubation times emphasizing the fact that esmolol is of excellent early recovery and extubation profiles.

CONCLUSION

Esmolol is advised to be used in preventing hyperdynamic status throughout extubation phase without extending recovery phase length.

Administration of Remifentanil in Establishing a more Stable Post-anesthesia Cardiovascular Status in Neurosurgical Procedures

INTRODUCTION

Emergence from general anesthesia and especially post-extubation phase are the stages associated with cardiovascular hyperdynamic status in which patients with increased intracranial pressure (ICP) could be affected by severe cardiac and or cerebral complications. Administering remifentanil could be helpful in maintaining the hemodynamic stability at the end of the surgery and recovery stages and reducing recovery phase length.

METHODS

In a double-blind prospective randomized clinical trial, 60 adult patients with ASA (American Society of Anesthesiologist) class of I-II scheduled to undergo elective neurosurgery operations were randomly divided into two groups receiving remifentanil and placebo as IV infusion within four minutes prior to extubation continued by an IV infusion for 10 minutes after extubation.

RESULTS

There was a significant difference between two groups regarding the changes of Mean Arterial Pressure after extubation and five minutes after extubation (P˂ 0.001).Remifentanil group compared with control group was of significant difference at all heart rate values after extubation (P< 0.001).

CONCLUSION

Remifentanil could be used in preventing hyperdynamic status throughout extubation phase without extending recovery phase length. However, administration of this medication should be performed cautiously.

Efficacy of clevidipine in controlling perioperative hypertension in neurosurgical patients: initial single-center experience

BACKGROUND

Acute blood pressure (BP) elevations in neurosurgical patients are associated with serious neurologic, cardiovascular, or surgical site complications. Clevidipine, an ultra-short-acting dihydropyridine calcium antagonist, has been shown to be efficacious and safe for acute hypertension in cardiac surgery. This study assessed the efficacy and safety of clevidipine in controlling perioperative hypertension in the neurosurgical setting.

METHODS

Patients scheduled for intracranial surgery were prospectively enrolled after giving consent. Clevidipine (0.5 mg/mL in 20% lipid solution, which was to be initiated at 10 mg/h and titrated to effect) was administered as the primary antihypertensive agent for perioperative hypertension, with target BPs of less than 130 mm Hg. Other vasoactive drugs were administered as needed for treating systolic BP (SBP) less than 90 mm Hg or greater than 130 mm Hg. The primary study endpoint was the proportion of patients not requiring rescue antihypertensives to maintain target SBP (<130 mm Hg).

RESULTS

Twenty-two patients were enrolled. One patient did not require antihypertensive therapy. Seventeen patients (17 of 21, 81%) were treated with clevidipine alone; one received clevidipine in the postanesthesia care unit only. Twenty-eight hypertensive episodes (defined as any new acute BP elevation requiring clevidipine initiation) were documented. SBP was reduced to target level within 15 minutes in 22 of 28 episodes (78.6%). Two mild hypotensive episodes occurred after the initiation of clevidipine infusion; these transient decreases in BP were treated with vasoactive drugs and resolved within 5 minutes.

CONCLUSIONS

Clevidipine is effective and safe for perioperative hypertension in patients undergoing intracranial procedures. Rapid control of BP is possible with higher starting doses. Drug effects resolved rapidly after drug discontinuation.

'Anesthesia' for awake neurosurgery

PURPOSE OF REVIEW

In this review we focus on recent findings in the anesthetic management of patients undergoing craniotomy while awake, and propose a structured approach to the clinical practice of 'anesthesia' for awake neurosurgery.

RECENT FINDINGS

The increasing use of functional neurosurgery and recent evidence favoring resection of tumor involving eloquent cortex has expanded the indications for awake craniotomy, a procedure needing a fully cooperative patient and expert intraoperative anesthetic management. Despite the shorter hospital stay, the more recently published studies have highlighted perioperative anesthetic complications and have proposed ways to improve anesthesia techniques for awake procedures in adults and children.

SUMMARY

Although anesthesia for awake craniotomy is usually a well tolerated procedure it requires an extensive knowledge of the principles underlying neuroanesthesia and of specific technical strategies including local anesthesia for scalp blockade, advanced airway management, dedicated sedation protocols, and skillful management of hemodynamics.