Supratentorial Craniotomy Research Articles

A protocol for postoperative admission of elective craniotomy patients to a non-ICU or step-down setting.

OBJECTIVE Selecting the appropriate patients undergoing craniotomy who can safely forgo postoperative intensive care unit (ICU) monitoring remains a source of debate. Through a multidisciplinary work group, the authors redefined their institutional care process for postoperative monitoring of patients undergoing elective craniotomy to include transfer from the postanesthesia care unit (PACU) to the neurosurgical floor. The hypothesis was that an appropriately selected group of patients undergoing craniotomy could be safely managed outside the ICU in the postoperative period. METHODS The work group developed and implemented a protocol for transfer of patients to the neurosurgical floor after 4-hour recovery in the PACU following elective craniotomy for supratentorial tumor. Criteria included hemodynamically stable adults without significant new postoperative neurological impairment. Data were prospectively collected including patient demographics, clinical characteristics, surgical details, postoperative complications, and events surrounding transfer to a higher level of care. RESULTS Of the first 200 consecutive patients admitted to the floor, 5 underwent escalation of care in the first 48 hours. Three of these escalations were for agitation, 1 for seizure, and 1 for neurological change. Ninety-eight percent of patients meeting criteria for transfer to the floor were managed without incident. No patient experienced a major complication or any permanent morbidity or mortality following this care pathway. CONCLUSIONS Care of patients undergoing uneventful elective supratentorial craniotomy for tumor on a neurosurgical floor after 4 hours of PACU monitoring appears to be a safe practice in this patient population. This tailored practice safely optimized hospital resources, is financially responsible, and is a strong tool for improving health care value.

Bitemporal Postoperative Hemorrhage Following Pterional Craniotomy for the Treatment of an Internal Carotid Aneurysm

Introduction Postoperative hemorrhage is a well-known complication after intracranial surgeries. It usually occurs at the site of the operation; however, there are many reports of cerebellar hemorrhage following supratentorial craniotomies. Despite that, there are only three cases of multiple postoperative supratentorial hemorrhages (distant from the site of the operation) following aneurysm clipping in the current literature. Case Report A 52-year-old previously healthy woman underwent a left pterional craniotomy for the clipping of an unruptured aneurysm. The surgery was performed without any intraoperative rupture or other occurrences. On the follow-up computed tomography (CT) scan performed 24h after surgery, bilateral posterior temporal lobe hematomas were identified, and they had no relation to the surgical site. The patient developed symptomatic vasospasm, with right-sided hemiparesis. This complication was treated conservatively, and the outcome was good. Conclusions Intracerebral hemorrhage far from the site of the craniotomy is an infrequent complication after neurosurgical procedures, especially in vascular neurosurgery. The present report warns of the occurrence of this entity even in asymptomatic patients.

Remote cerebellar haemorrhage after placement of an external ventricular drainage for acute hydrocephalus: A case report

IntroductionRemote cerebellar haemorrhage (RCH) is a rare complication following a craniotomy. This generally benign phenomenon is an identifiable complication of supratentorial craniotomies and should not be mistaken with other pathologies. The most common presenting symptom is a decrease in the level of consciousness but in some cases the RCH may be asymptomatic and accidentally discovered in follow-up CT scans. Case reportA 70-year-old man was admitted to our emergency department with sudden mental status deterioration. A head CT scan was carried out and an acute hydrocephalus was diagnosed. The patient was transferred to the operating room for external ventricular drainage (EVD) placement via a frontal burr-hole. At 24hours, the patient made a complete neurological recovery. On third postoperative day, a follow-up CT scan showed an asymptomatic right remote cerebellar haemorrhage. The MRI assessment confirmed the diagnosis. The EVD was removed on the 6th postoperative day and the patient was discharged after one week with no further symptoms. DiscussionThis case report is the first documented case, to our knowledge, of a remote cerebellar haemorrhage after placement of external ventricular drainage via a frontal burr-hole. The precise aetiology of remote cerebellar haemorrhage remains unclear. One of the most accepted theories is the “cerebellar sag” explanation, which defends hypothesis that peri-operative over drainage of cerebrospinal fluid (CSF) is the main mechanism involved. Further investigation is required to understand the pathogenesis and risk factors for the occurrence of this phenomenon.

Comparative evaluation of morphine and fentanyl for emergence following supratentorial craniotomy

Background: The emergence from anaesthesia is a very crucial aspect in neurosurgical patients due to the need for evaluation of neurological status in the immediate post-operative period. The present study evaluates the emergence characteristics following administration of morphine as compared to shorter-acting opioid, fentanyl in patients undergoing supratentorial craniotomy. Methods: A total of 84 patients were included in the study. The patients either received morphine 0.1 mg/kg before induction or fentanyl 2 mcg/kg body weight at induction, 1 mcg/kg before skin incision and at the beginning of dural closure. Doses of both opioids were repeated as judged clinically during surgery. Following surgery, the trachea was extubated after reversal of residual neuromuscular blockade, and the emergence characteristics of patients in the two groups were compared. Results: The mean time to emergence was 8.5 ± 3.7 min in morphine group whereas it was 7.8 ± 5.1 min in fentanyl group ( P = 0.11). Conclusions: Morphine appears similar to fentanyl for facilitating early emergence in patients undergoing an elective supratentorial craniotomy.

The risk of hypotension and seizures in patients receiving prophylactic anti-epileptic drugs for supratentorial craniotomy.

Perioperative seizure prophylaxis with antiepileptic drugs (AED) has been advocated in patients undergoing supratentorial craniotomy. The practice remains controversial. The reasoning presupposes that the possibility of an adverse drug reaction from the AED is lower than the probability of harm from a seizure. Even short periods of hypotension during the operation can lead to acute kidney and myocardial injury. We retrospectively evaluated cardiovascular effects and tolerability of levetiracetam (LEV) alone, LEV and lacosamid (LCM) as compared to phenytoin (PHT). After IRB approval, the charts of individuals who underwent craniotomy from April 2007 to September 2011 were reviewed. Those receiving PHT were compared to those receiving LEV alone and LEV/LCM. The patient data included demographic, indication and procedure related data. The cumulative dose of norepinephrine (NET), atropine (ATR) and the change in systolic blood pressure during and after the administration of the AED were analyzed. Five hundred thirty-eight patients were screened of which 122 were included for analysis. 40 patients with primary or secondary supratentorial brain tumors received LEV (19 female, 21 male; mean age 56 years), 41 patients received LEV/ LCM (16 female, 25 male; mean age 56 years) and 41 patients received PHT (15 female, 26 male; mean age 50 years). The commonest indications for craniotomy were glioblastoma (N.=14 vs. N.=12 vs. N.=15), meningiomas (N.=9 vs. N.=7 vs. N.=10), low-grade gliomas (N.=6 vs. N.=13 vs. N.=6) and brain metastases (N.=5 vs. N.=4 vs. N.=5). 1 LEV/LCM patient (2%) and 4 PHT patients (4.5%) had a seizure despite prophylaxis. Possible side effects were observed in 2 patients associated with PHT. During anesthesia there was a significant drop in systolic blood pressure in the PHT group after administration of the AED perioperatively when compared to LEV (P=0.001) and LEV/LCM (P≤0.0001) respectively. The mean cumulative doses of NET and ATR over the course of the operation did not differ significantly. LEV alone and in combination with LCM for patients without and with symptomatic epilepsy as seizure prophylaxis provides a safe and feasible alternative to PHT. PHT was associated with an unfavorable drop in blood pressure during anesthesia and more adverse reactions.

Dexmedetomidine versus labetalol infusions for controlling emergence hypertension in cranial surgeries for supratentorial tumors

BackgroundAcute hypertension is a common accompaniment during emergence from anesthesia especially in intracranial neurosurgical procedures and may be associated with the development of intracranial hematoma. Although various drugs have been evaluated, management of emergence hypertension in this subset of patients continues to be a challenge for anesthesiologists.MethodologySeventy-five patients ASA (I-II) scheduled for supratentorial craniotomy under general anesthesia were randomly allocated to one of three groups at the time of dural closure: Group “dex” received dexmedetomidine infusion in a rate of 1 μg/kg/hr, Group “labetalol” received labetalol infusion in a rate of 0.5 mg/kg/hr, and Group “control” a control group where patients received saline infusion at the same rate of dexmedetomidine and labetalol. Hypertensive episodes were managed with nitroglycerin at a dose starting from 1 μg/kg/min if systolic blood pressure exceeded 25% of its preinduction value. Hemodynamic parameters as well as the number of patients, the total dose of nitroglycerin required in each group and the time to extubation were recorded.ResultsDexmedetomidine and labetalol had a significant effect in reducing SBP, MAP, DBP, HR during emergence from anesthesia, with more reduction of the SBP, MAP and DBP in the dexmedetomidine group and of the HR in the labetalol group in comparison with the other two groups. The number of patients needing nitroglycerin was 8 representing 32% of patients in dexmedetomidine group, 5 representing 20% of patients in labetalol group and 22 representing 88% of patients in control group (P value = 0.032). Time to emergence from anesthesia was comparable in the three groups.ConclusionBoth dexmedetomidine and labetalol had favorable effects on hemodynamics at time of emergence from anesthesia in comparison with control group without prolongation of the time of extubation.

Lidocaine Reduces Acute Postoperative Pain After Supratentorial Tumor Surgery in the PACU: A Secondary Finding From a Randomized, Controlled Trial.

Perioperative lidocaine infusion has been reported to reduce postoperative pain in patients after abdominal surgery; however, no study has examined lidocaine's effect on acute postoperative pain after supratentorial tumor surgery. A total of 94 patients scheduled for supratentorial craniotomy were enrolled. Patients received either lidocaine through an intravenous bolus (1.5 mg/kg) after induction followed by infusion at a rate of 2 mg/kg/h until the end of surgery or the same volume of normal saline. Mean arterial blood pressure, heart rate, and bispectral index were recorded at different intraoperative time points. Patients were assessed for pain in the postoperative anesthesia care unit (PACU) by the numeric rating scale (NRS). Other complications including hypertension, tachycardia, dysphoria, and postoperative nausea and vomiting (PONV) were reported. There was no significant difference between the normal saline and lidocaine group for mean arterial blood pressure, heart rate, and bispectral index at any time point (P>0.05). There was no significant difference in the incidence of hypertension, tachycardia, dysphoria, and PONV between groups (P>0.05). The incidence of mild pain (NRS between 1 and 3) after surgery in PACU was lower in lidocaine group than that in the normal saline group (P=0.014); the number of patients with an NRS pain score of 0 before leaving the PACU was significantly greater in the lidocaine group. No patient in either group had moderate or severe pain. Intraoperative infusion of lidocaine significantly decreases the proportion of patients with acute pain after supratentorial tumor surgery in the PACU.

A Superior Cerebellar Convexity Two-Part Craniotomy to Access the Paramedian Supra and Infratentorial Space: Technical Note.

A craniotomy over the superior cerebellar convexity for approaches to this region typically involves a small infratentorial craniotomy and then drilling down of the bone to expose some portion of the transverse/sigmoid sinuses. The authors describe the anatomy of the region and the method for a two-part paramedian occipital and suboccipital craniotomy (supra and infratentorial) that may have time-saving, safety, and cosmetic advantages. For this technique, a supratentorial craniotomy is used to expose the transverse sinus from above, and subsequently, dissection across the sinus over the cerebellar convexity can be done under direct vision. The two bone pieces are joined on the inner table side while plates for fixation above the superior nuchal line can be counter-sunk to avoid post-operative pain from the prominence of screws. There is no need for cranioplasty materials since there is no burring down of bone for adequate exposure of the transverse sinus. The technique has been used by two senior surgeons over the years convincing them of the speed, safety, and utility of the technique. Here, the authors present a single example of the technique.

Postoperative analgesia for supratentorial craniotomy

ObjectivesThe prevalence of moderate to severe pain is high in patients following craniotomy. Although optimal analgesic therapy is mandatory, there is no consensus regarding analgesic regimen for post-craniotomy pain exists. This study aimed to investigate the effects of morphine and non-opioid analgesics on postcraniotomy pain. Patients and methodsThis prospective, randomized, double blind, placebo controlled study included eighty three patients (ASA 1, II, and III) scheduled for elective supratentorial craniotomy. Intravenous dexketoprofen, paracetamol and metamizol were investigated for their effects on pain intensity, morphine consumption and morphine related side effects during the first 24h following supratentorial craniotomy. Patients were treated with morphine based patient controlled analgesia (PCA) for 24h following surgery and randomized to receive supplemental IV dexketoprofen 50mg, paracetamol 1g, metamizol 1g or placebo. The primary endpoint was pain intensity, secondary endpoint was the effects on morphine consumption and related side effects. ResultsWhen the whole study period was analyzed with repeated measures of ANOVA, the pain intensity, cumulative morphine consumption and related side effects were not different among the groups (p>0.05). ConclusionThis study showed that the use of morphine based PCA prevented moderate to severe postoperative pain without causing any life threatening side effects in patients undergoing supratentorial craniotomy with a vigilant follow up during postoperative 24h. Although we could not demonstrate statistically significant effect of supplemental analgesics on morphine consumption, it was lower in dexketoprofen and metamizol groups than control group.

Does bradycardia and hypertension always equal to Cushing’s response during supratentorial craniotomy?

Does bradycardia and hypertension always equal to Cushing’s response during supratentorial craniotomy?

Remote cerebellar hemorrhage after supratentorial procedures (part 1): a systematic review.

A remote cerebellar hemorrhage (RCH) is a spontaneous bleeding in the posterior fossa, which may rarely occurs as a complication of supratentorial procedures, and it shows a typical bleeding pattern defined "the zebra sign." However, its pathophysiology still remains unknown. We performed a comprehensive review collecting all cases of RCH after supratentorial craniotomies reported in literature in order to identify the most frequently associated procedures and the possible risk factors. We assessed percentages of incidence and 95% confidence intervals of all demographic, neuroradiological, and clinical features of the patients. Univariate and multivariate analyses were used to evaluate their association with outcome. We included 49 articles reporting 209 patients with a mean age of 49.09 ± 17.07years and a male/female ratio 130/77. A RCH was more frequently reported as a complication of supratentorial craniotomies for intracranial aneurysms, tumors debulking, and lobectomies. In the majority of cases, RCH occurrence was associated with impairment of consciousness, although some patients remained asymptomatic or showed only slight cerebellar signs. Coagulation disorders, perioperative cerebrospinal fluid drainage, hypertension, and seizures were the most frequently reported risk factors. Zebra sign was the most common bleeding pattern, being observed in about 65% out of the cases, followed by parenchymal hematoma and mixed hemorrhage in similar percentages. A multivariate analysis showed that symptomatic onset and intake of antiplatelets/anticoagulants within a week from surgery were independent predictors of poor outcome. However, about 75% out of patients showed a good outcome and a RCH often appeared as a benign and self-limiting condition, which usually did not require surgical treatment, but only prolonged clinical surveillance, unless in the event of the occurrence of complications.

Knowledge and attitude about seizures among caregivers of patients with supratentorial craniotomy

Among the psychiatric co-morbidities in epilepsy, anxiety disorders are highly frequent and have profound influence on the quality of life of epilepsy patients. Moringa oleifera Lam. (Moringaceae) is used in traditional medicine to treat various ailments including anxiety and epilepsy. However, no scientific evidence exists to support its use. We studied antiepileptic and anxiolytic activities of aqueous extract of Moringa oleifera Lam. leaves (AEMO).Antiepileptic activity was evaluated using pentylenetetrazole (PTZ) induced seizure and maximum electroshock (MES) induced seizure test and anxiolytic activity was evaluated using elevated plus maze, light/dark box and hole board test.In present study, AEMO (250, 375 and 500 mg/kg, i.p.) demonstrated significant antiepileptic and anxiolytic effects. To study involvement of GABA in anxiolytic and antiepileptic activity of AEMO, we also evaluated effect of AEMO on Baclofen induced catatonia, a GABA mediated behavior, wherein AEMO significantly potentiated (preponed) baclofen induced catatonia, which is suggestive of its GABA mimetic action.Thus, it may be concluded that aqueous extract of M. oleifera possess anxiolytic and antiepileptic effects possibly mediated via of GABA mimetic action and these findings authenticate the traditional claims about use of Moringa oleifera in treatment of epilepsy and anxiety.

Lidocaine Did Not Reduce Neuropsychological-Cognitive Decline in Patients 6 Months After Supratentorial Tumor Surgery: A Randomized, Controlled Trial.

: There is equivocal evidence examining cognitive improvement in response to lidocaine during cardiac surgery; however, no study has examined its effect on postoperative neuropsychological-cognitive decline after supratentorial tumor surgery. Ninety-four patients scheduled for supratentorial craniotomy were enrolled. Patients received either a dose of lidocaine (2%) via an intravenous bolus (1.5 mg/kg) after induction followed by an infusion at a rate of 2 mg/kg/h until the end of surgery (Lidocaine group) or the same volume of normal saline. The neuropsychological-cognitive decline was evaluated using the following tests: the Mini-Mental State Examination, the Information-Memory-Concentration test, the Hamilton Rating Scale for Depression, and the Hamilton Rating Scale for Anxiety. The cerebral oxygen extraction ratio and the difference in lactic acid levels between the bulb of the jugular vein and a peripheral artery were measured. Eighty patients completed the neuropsychological tests, with 40 patients in each group. The incidence of postoperative decline at up to 6 months in the Lidocaine group was not significantly different than that in the Normal saline group. When the 2 cognitive tests were examined independent of the other tests, there was no difference between groups at 6 months. The cerebral oxygen extraction ratio was significantly lower in the Lidocaine group after surgery (P<0.05), and the arteriovenous difference of lactic acid was lower in the Lidocaine group (P<0.05). Intraoperative infusion of lidocaine does not significantly decrease the incidence of postoperative neuropsychological-cognitive decline in patients 6 months after supratentorial tumor surgery.

A prospective, comparative, randomised, double blind study on the efficacy of addition of clonidine to 0.25% bupivacaine in scalp block for supratentorial craniotomies.

Background and Aims:Scalp blocks combined with general anaesthesia reduce pin and incision response, along with providing stable perioperative haemodynamics and analgesia. Clonidine has proved to be a valuable additive in infiltrative blocks. We studied the efficacy and safety of addition of clonidine 2 μg/kg to scalp block with 0.25% bupivacaine (Group B) versus plain 0.25% bupivacaine (Group A) for supratentorial craniotomies.Methods:Sixty patients were randomly divided into two groups to receive scalp block: Group A (with 0.25% bupivacaine) and Group B (with 0.25% bupivacaine and clonidine (2 μg/kg). Bilateral scalp block was given immediately after induction. All the patients received propofol based general anaesthesia. Intraoperatively, propofol infusion was maintained at 75 to 100 μg/kg/h up to dura closure and reduced to 50-75 μg/kg/h up to skin closure with atracurium infusion stopped at dura closure. Heart rate (HR) and mean arterial pressure (MAP) were monitored at pin insertion, at 5 minute intervals from incision till dura opening and again at 5 minute interval from dura closure up to skin closure. Fentanyl 0.5 μg/kg was given if a 20% increase in either HR and/or MAP was observed. Postoperative haemodynamics and verbal rating scores (VRS) were recorded. When the VRS score increased above 3, rescue analgesia was given. Any intraoperative haemodynamic complications were noted.Results:Group A showed a significant increase in haemodynamic variables during the perioperative period as compared to group B (P < 0.05). Addition of clonidine 2 μg/kg in the infiltrative block also provided significantly prolonged postoperative analgesia.Conclusions:Addition of clonidine to scalp block provided better perioperative haemodynamic stability and significantly prolonged analgesia.

Effect of pre-incisional anterior scalp block on intraoperative opioid consumption in adult patients undergoing elective craniotomy to remove tumor: study protocol for a randomized double-blind trial

Background: Scalp block is a selective nerve block technique to inhibit the afferent input from nerves that innervate the scalp, including supratrochlear, supraorbital, zygomaticofacial, and zygomaticotemporal nerves for the anterior scalp. The greater and lesser occipital nerves innervate the posterior scalp. Methods/Design: This study is a prospective, randomized, double-blind, placebo-controlled trial, which will be performed to examine the benefits of a pre-incisional anterior scalp block with 0.5% bupivacaine in adult patients who are scheduled for supratentorial craniotomy to remove tumor. Primary outcome will be the difference of intraoperative fentanyl consumption between patients who receive anterior scalp block with 0.5% bupivacaine and those who receive normal saline solution administration. Secondary outcomes will be the hemodynamic changes from preoperative baseline at a skull pin insertion and the time from the end of surgery to successful extubation. Discussion: Skull pin insertion is known as the strongest stimulus prior to craniotomy. The results from previous studies are inconclusive regarding the advantage of scalp block as a pre-emptive analgesic technique. This study will fill this knowledge gap, and examine whether this technique is worth performing as a standard technique. Trial registration: ClinicalTrials.gov identifier: NCT02057367; registered in February 2014. Ethics: This study protocol was approved by the Ethics Committee of Maharaj Nakorn Chiang Mai Hospital, Chiang Mai University, Thailand (approval number: ANE-2556-01510) and will be performed in accordance with the Declaration of Helsinki. Informed consent: Written informed consent will be obtained from participants prior to inclusion in this study.

A comparison of equivolume, equiosmolar solutions of hypertonic saline and mannitol for brain relaxation during elective supratentorial craniotomy

Background: Hyperosmolar solutions have been used in neurosurgery to reduce brain volume and facilitate surgical exposure. The purpose of this study was to compare the effects of equivolume, equiosmolar solutions of mannitol and hypertonic saline (HS) on brain relaxation, intensive care unit (ICU) and hospital stay, postoperative outcomes and incidence of side-effects in patients undergoing elective supratentorial craniotomy. Methods: In a randomised, prospective, double-blind study, 60 patients undergoing elective supratentorial craniotomy were randomised 1:1 to receive 3 ml/kg of either 20% mannitol or 3% HS. The primary outcome was the surgical condition of the brain assessed by the neurosurgeon using a 4-point scale after opening the dura (1 = relaxed, 2 = satisfactory, 3 = firm and 4 = bulging). Secondary outcomes were electrolytes, blood gases, plasma osmolality and haemodynamic variables measured at 0 min, 30 min, 2 h and 6 h after infusion. Also, predefined postoperative complications, length of ICU and hospital stay were recorded. Appropriate statistical tests were used for comparison; p < 0.05 was considered significant. Results: There was no difference in brain relaxation [mannitol, 1(1–3) versus HS, 1(1.4) points; p = 0.55]. Patients with brain midline shift showed a worse response to hyperosmolar solutions than those without midline shift: 37% versus 8%, respectively; OR = 6.6 (95% CI, 1.54–28.83); p = 0.006. Plasma osmolality increased during the study period (6 h) in both the groups (p < 0.05 compared with baseline). No significant differences in postoperative complications or length of ICU and hospital stay were observed between the groups. Conclusions: Single doses of 3 ml/kg of 20% mannitol and 3% HS are safe and effective for intraoperative brain debulking during elective supratentorial craniotomy, but less effective in patients with pre-existing mass effect and midline shift.

Intraoperative and postoperative anaesthetic and analgesic effect of multipoint transcutaneous electrical acupuncture stimulation combined with sufentanil anaesthesia in patients undergoing supratentorial craniotomy.

To investigate the anaesthetic and analgesic effect of multipoint transcutaneous electrical acupuncture stimulation (TEAS) during supratentorial tumour resection for postoperative recovery and side effects. In a blinded clinical trial, 92 patients scheduled for supratentorial craniotomy under general anaesthesia were randomly allocated into either a multipoint TEAS (n=46) or a sham TEAS group (n=46). All patients received total intravenous anaesthesia (TIVA) with propofol and sufentanil. The target concentration of sufentanil was adjusted and recorded according to mean arterial pressure (MAP), heart rate (HR) and bispectral index (BIS). Patients in the TEAS group received TEAS 30 min before anaesthesia induction and this was maintained throughout the operation at four pairs of acupuncture points. Postoperative pain, recovery and side effects were evaluated. Eighty-eight patients completed the study. Continuous monitoring of MAP, HR and BIS showed stable values with no significant differences between the two groups (p>0.05). Sufentanil target plasma concentration in TEAS patients was significantly lower at some time points during supratentorial craniotomy, and total sufentanil consumption was significantly higher in the sham group (p<0.05). Postoperative recovery and pain were significantly improved by TEAS (p<0.001), without the postoperative side effects. Multipoint TEAS at both proximal and distal points combined with TIVA can significantly decrease intraoperative sufentanil requirements, increase pain relief on postoperative day 1 and improve postoperative recovery of patients during supratentorial tumour resection, with no significant increase of side effects. These findings suggest that multipoint TEAS may be clinically effective as an adjunct to analgesia in intraoperative anaesthesia and postoperative pain treatment and may speed recovery. Chinese Clinical Trial Registry (registration number ChiCTR-TRC-10001078).

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

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). 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. 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). 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 Moderate Hyperventilation on Jugular Bulb Gases under Propofol or Isoflurane Anesthesia during Supratentorial Craniotomy.

Background:The optimal ventilated status under total intravenous or inhalation anesthesia in neurosurgical patients with a supratentorial tumor has not been ascertained. The purpose of this study was to intraoperatively compare the effects of moderate hyperventilation on the jugular bulb oxygen saturation (SjO2), cerebral oxygen extraction ratio (O2ER), mean arterial blood pressure (MAP), and heart rate (HR) in patients with a supratentorial tumor under different anesthetic regimens.Methods:Twenty adult patients suffered from supratentorial tumors were randomly assigned to receive a propofol infusion followed by isoflurane anesthesia after a 30-min stabilization period or isoflurane followed by propofol. The patients were randomized to one of the following two treatment sequences: hyperventilation followed by normoventilation or normoventilation followed by hyperventilation during isoflurane or propofol anesthesia, respectively. The ventilation and end-tidal CO2 tension were maintained at a constant level for 20 min. Radial arterial and jugular bulb catheters were inserted for the blood gas sampling. At the end of each study period, we measured the change in the arterial and jugular bulb blood gases.Results:The mean value of the jugular bulb oxygen saturation (SjO2) significantly decreased, and the oxygen extraction ratio (O2ER) significantly increased under isoflurane or propofol anesthesia during hyperventilation compared with those during normoventilation (SjO2: t = −2.728, P = 0.011 or t = −3.504, P = 0.001; O2ER: t = 2.484, P = 0.020 or t = 2.892, P = 0.009). The SjO2 significantly decreased, and the O2ER significantly increased under propofol anesthesia compared with those values under isoflurane anesthesia during moderate hyperventilation (SjO2: t = −2.769, P = 0.012; O2ER: t = 2.719, P = 0.013). In the study, no significant changes in the SjO2 and the O2ER were observed under propofol compared with those values under isoflurane during normoventilation.Conclusions:Our results suggest that the optimal ventilated status under propofol or isoflurane anesthesia in neurosurgical patients varies. Hyperventilation under propofol anesthesia should be cautiously performed in neurosurgery to maintain an improved balance between the cerebral oxygen supply and demand.

Monitoring the depth of anaesthesia using the new modified entropy sensors during supratentorial craniotomy: Our experience

Abstract Background: Monitoring the depth of anaesthesia can be a challenge in patients undergoing supratentorial craniotomy because the conventional sensors for both bispectral index and entropy monitors lose their contact with a brain after scalp elevation. The new sensors for the entropy monitor are more flexible and can be placed in different locations. The purpose of this study was to determine the feasibility on the use of new GE entropy sensors in monitoring depth of anaesthesia in patients undergoing supratentorial craniotomy. Materials and Methods: We retrospectively reviewed the data from 20 consecutive patients undergoing supratentorial craniotomy who had the monitoring of the depth of anaesthesia using modified entropy sensors. Prior to the induction of anaesthesia, the new GE entropy sensor (P/N M1038681) was applied in a modified fashion. We measured the state entropy (SE) and response entropy (RE) at 12 perioperative time points. Entropy values were compared with the clinical indices of depth of anaesthesia. Results: Data from 20 consecutive patients (orbitozygomatic craniotomy [10] and bifrontal craniotomy [10]) were analysed. Monitoring was possible in all the patients. The changes in entropy values correlated with clinical indices of depth of anaesthesia. However, some patients showed variations in absolute values (RE and SE) during the intraoperative period without any changes in the level of anaesthetic depth. Conclusions: Monitoring the depth of anaesthesia is feasible with the use of new entropy sensors in patients undergoing supratentorial craniotomy. In contrast to standard sensors, the new sensors offer flexibility with the placement.