Changes in central venous oxygen saturation, lactates, and ST segment changes in a V lead ECG with changes in hemoglobin in neurosurgical patients undergoing craniotomy and tumor excision: A prospective observational study.

BACKGROUND AND AIMS: The aim of the study was to observe the trends in central venous oxygen saturation (ScvO2), lactate, and ST segment changes with change in hemoglobin in patients undergoing acute blood loss during surgery and to assess their role as blood transfusion trigger. MATERIAL AND METHODS: Seventy-seven consecutive patients undergoing craniotomy at a tertiary care institution were recruited for this study after obtaining written, informed consent. After establishing standard monitoring, anesthesia was induced with standard anesthetic protocol. Hemodynamic parameters such as heart rate, blood pressure (mean, systolic, diastolic), pulse pressure variation (PPV), and physiological parameters such as lactate, ScvO2, ST segment changes were checked at baseline, before and after blood transfusion and at the end of the procedure. STATISTICAL ANALYSIS: Comparison of the mean and standard deviation for the hemodynamic parameters was performed between the transfused and nontransfused patient groups. Pearson correlation test was done to assess the correlation between the covariates. Receiver operating characteristic (ROC) curve was constructed for the ScvO2 variable, which was used as a transfusion trigger and the cutoff value at 100% sensitivity and 75% specificity was constructed. Linear regression analysis was done between the change in hemoglobin and the change in ScvO2 and change in hemoglobin and change in the ST segment. RESULTS: There was a statistically significant positive correlation between the change in ScvO2 and change in hemoglobin during acute blood loss with a regression coefficient of 0.8 and also between change in ST segment and hemoglobin with a regression coefficient of -0.132. No significant change was observed with lactate. The ROC showed a ScvO2 cutoff of 64.5% with a 100% sensitivity and 75% specificity with area under curve of 0.896 for blood transfusion requirement. CONCLUSIONS: We conclude that ScvO2 and ST change may be considered as physiological transfusion triggers in patients requiring blood transfusion in the intraoperative period.

A comparison of the recovery profiles of desflurane and isoflurane anesthesia in patients undergoing elective supratentorial craniotomy: A randomized controlled trial.

CONTEXT: Few studies have compared recovery profiles of desflurane and isoflurane for patients undergoing elective supratentorial craniotomy. It is not known if the choice of inhalational agent can affect the duration of transient postoperative neurological deficits in these patients. AIMS: To compare the effect of desflurane and isoflurane on time-to-emergence and time-to-recovery of transient postoperative neurological deficits in patients undergoing supratentorial craniotomy. SETTINGS AND DESIGN: Prospective, double-blinded, randomized controlled trial at a tertiary care hospital. METHODS AND MATERIALS: We randomly assigned 60 patients to receive either desflurane or isoflurane during elective supratentorial craniotomy for intra-axial mass lesions. Time-to-emergence and time-to-recovery of transient postoperative neurological deficits were recorded and compared. STATISTICAL ANALYSIS USED: Parametric variables were compared by the Student's t test. Baseline data was compared using Pearson's chi square test, Fisher's exact test and two proportion Z test. RESULTS: There was a 35.7%, 31.4% and 34.5% reduction in median times to eye opening, obeying commands and orientation in the desflurane group (n=27) as compared to the isoflurane group (n=28). Five patients were enrolled but not included for analysis-Twelve patients sustained transient neurological deficits after surgery (desflurane, n=3; isoflurane, n=9). No significant difference in the time-to-recovery of transient postoperative neurological deficits was observed. CONCLUSIONS: Desflurane significantly reduced emergence times, and was able to facilitate an early neurological examination for patients. Additional studies are required to establish the impact of inhalational agents on transient postoperative neurological deficits.

A Randomized Controlled Trial Studying the Role of Dexamethasone in Scalp Nerve Blocks for Supratentorial Craniotomy.

BACKGROUND: The aim of this double-blinded randomized control study was to examine the role of the steroid dexamethasone as an adjuvant to lignocaine and ropivacaine in scalp nerve blocks in adults undergoing supratentorial craniotomy under general anesthesia. We compared the intraoperative anesthetic and postoperative analgesic requirement with and without the addition of dexamethasone to the local anesthetics. METHODS: The consented 90 patients were randomized into 2 groups: one group received 8 mg (2 mL) of dexamethasone, whereas the other received 2 mL of normal saline along with the local anesthetics in the scalp nerve block administered soon after induction of general anesthesia. All patients received oral/intravenous dexamethasone perioperatively to decrease cerebral edema. The general anesthetic technique for induction, maintenance, and recovery was standardized in the 2 groups. The primary outcome assessed was the time to administration of the first dose of analgesic postoperatively. The secondary outcomes included intraoperative opioid requirement, time to emergence, and incidence of postoperative nausea and vomiting. RESULTS: There was no significant difference between the dexamethasone and saline groups with respect to time to first analgesic requirement, intraoperative fentanyl requirements, time to emergence from general anesthesia, and incidence of postoperative nausea and vomiting. CONCLUSIONS: Addition of dexamethasone as an adjuvant to local anesthetics in scalp nerve blocks in the setting of perioperative steroid therapy does not appear to provide any additional benefit with respect to prolongation of the duration of the block.

Intra-Operative Fluid Management in Adult Neurosurgical Patients Undergoing Intracranial Tumour Surgery: Randomised Control Trial Comparing Pulse Pressure Variance (PPV) and Central Venous Pressure (CVP).

INTRODUCTION: Fluid management in neurosurgery presents specific challenges to the anaesthesiologist. Dynamic para-meters like Pulse Pressure Variation (PPV) have been used successfully to guide fluid management. AIM: To compare PPV against Central Venous Pressure (CVP) in neurosurgical patients to assess hemodynamic stability and perfusion status. MATERIALS AND METHODS: This was a single centre prospective randomised control trial at a tertiary care centre. A total of 60 patients undergoing intracranial tumour excision in supine and lateral positions were randomised to two groups (Group 1, CVP n=30), (Group 2, PPV n=30). Intra-operative fluid management was titrated to maintain baseline CVP in Group 1(5-10cm of water) and in Group 2 fluids were given to maintain PPV less than 13%. Acid base status, vital signs and blood loss were monitored. RESULTS: Although intra-operative hypotension and acid base changes were comparable between the groups, the patients in the CVP group had more episodes of hypotension requiring fluid boluses in the first 24 hours post surgery. {CVP group median (25, 75) 2400ml (1850, 3110) versus PPV group 2100ml (1350, 2200) p=0.03} The patients in the PPV group received more fluids than the CVP group which was clinically significant. {2250 ml (1500, 3000) versus 1500ml (1200, 2000) median (25, 75) (p=0.002)}. The blood loss was not significantly different between the groups The median blood loss in the CVP group was 600ml and in the PPV group was 850 ml; p value 0.09. CONCLUSION: PPV can be used as a reliable index to guide fluid management in neurosurgical patients undergoing tumour excision surgery in supine and lateral positions and can effectively augment CVP as a guide to fluid management. Patients in PPV group had better hemodynamic stability and less post operative fluid requirement.

Comparison of the effect of lignocaine instilled through the endotracheal tube and intravenous lignocaine on the extubation response in patients undergoing craniotomy with skull pins: A randomized double blind clinical trial.

BACKGROUND: A desirable combination of smooth extubation and an awake patient after neurosurgical procedures is difficult to achieve in patients with skull pins. Lignocaine instilled into endotracheal tube has been reported to suppress cough by a local mucosal anesthetizing effect. We aimed to evaluate if this effect will last till extubation, if given before pin removal. MATERIALS AND METHODS: A total of 114 patients undergoing elective craniotomy were divided into three groups and were given 1 mg/kg of intravenous (IV), 2% lignocaine (Group 1), placebo (Group 2) and 1 mg/kg of 2% lignocaine sprayed down the endotracheal tube (Group 3) before skull pin removal. The effectiveness of each to blunt extubation response was compared. Plasma levels of lignocaine were measured 10 min after administration of the study drug and at extubation. Sedation scores were noted, immediately after extubation and 10 min later. RESULTS: Two percent of lignocaine instilled through endotracheal route was not superior to the IV route or placebo in attenuating cough or hemodynamic response at extubation when given 20-30 min before extubation. The plasma levels of lignocaine (0.8 µg/ml) were not high enough even at the end of 10 min to have a suppressive effect on cough if given IV or intratracheally (IT). Lignocaine did not delay awakening in these groups. CONCLUSION: IT lignocaine in the dose of 1 mg/kg does not prevent cough at extubation if given 20-30 min before extubation. If the action is by a local mucosal anesthetizing effect, it does not last for 20-30 min to cover the period from pin removal to extubation.

Preoperative fasting in children: An audit and its implications in a tertiary care hospital.

BACKGROUND: Prolonged preoperative fasting in children is a common problem, especially in highvolume centers. All international professional society guidelines for preoperative fasting recommend 2 h for clear fluids, 4 h for breast milk and 6 h for solids, nonhuman and formula milk in children. These guidelines are rarely adhered to in practice. AIMS: An audit was undertaken to determine the length of preoperative fasting time in children and its causes. SETTINGS AND DESIGN: Cross-sectional study of 50 children below 15 years posted for elective surgeries. MATERIALS AND METHODS: An initial audit was performed at our institution on preoperative fasting time in 50 children below 15 years of age for elective surgeries. The mean preoperative fasting times were found to be much longer than the recommended times. Ward nurses were then educated about internationally recommended preoperative fasting guidelines in children. Anesthesiologists started coordinating with surgeons and ward nurses to prescribe water for children waiting for more than 2 h based on changes in surgery schedule by instructing ward nurses through telephone on the day of surgery. A reaudit was done 6 months after the initial audit. STATISTICAL ANALYSIS USED: SPSS 16 software. RESULTS: The initial audit revealed a mean preoperative fasting time of 11.25 h and 9.25 h for solids and water, respectively. Incorrect orders by ward nurses (74%) and change in the surgical schedule (32%) were important causes. After changing the preoperative system, mean preoperative fasting times in children decreased to 9 h and 4 h for solids and water, respectively in reaudit. Change in surgical schedule (30%) was the major cause for prolonged preoperative fasting in reaudit. CONCLUSIONS: Simple steps such as education of ward nurses and better coordination among the anesthesiologists, surgeons and nurses can greatly reduce unnecessary preoperative starvation in children.

Awake craniotomy and electrophysiological mapping for eloquent area tumours.

OBJECTIVE: An awake craniotomy facilitates radical excision of eloquent area gliomas and ensures neural integrity during the excision. The study describes our experience with 67 consecutive awake craniotomies for the excision of such tumours. METHODS: Sixty-seven patients with gliomas in or adjacent to eloquent areas were included in this study. The patient was awake during the procedure and intraoperative cortical and white matter stimulation was performed to safely maximize the extent of surgical resection. RESULTS: Of the 883 patients who underwent craniotomies for supratentorial intraaxial tumours during the study period, 84 were chosen for an awake craniotomy. Sixty-seven with a histological diagnosis of glioma were included in this study. There were 55 men and 12 women with a median age of 34.6 years. Forty-two (62.6%) patients had positive localization on cortical stimulation. In 6 (8.9%) patients white matter stimulation was positive, five of whom had responses at the end of a radical excision. In 3 patients who developed a neurological deficit during tumour removal, white matter stimulation was negative and cessation of the surgery did not result in neurological improvement. Sixteen patients (24.6%) had intraoperative neurological deficits at the time of wound closure, 9 (13.4%) of whom had persistent mild neurological deficits at discharge, while the remaining 7 improved to normal. At a mean follow-up of 40.8 months, only 4 (5.9%) of these 9 patients had persistent neurological deficits. CONCLUSION: Awake craniotomy for excision of eloquent area gliomas enable accurate mapping of motor and language areas as well as continuous neurological monitoring during tumour removal. Furthermore, positive responses on white matter stimulation indicate close proximity of eloquent cortex and projection fibres. This should alert the surgeon to the possibility of postoperative deficits to change the surgical strategy. Thus the surgeon can resect tumour safely, with the knowledge that he has not damaged neurological function up to that point in time thus maximizing the tumour resection and minimizing neurological deficits.

Oxidative stress-associated hypertension in surgically induced brain injury patients: effects of ß-blocker and angiotensin-converting enzyme inhibitor.

BACKGROUND: Postoperative hypertension is a common problem in patients undergoing surgical procedures, and the modification of this response could result in improved surgical outcome. Although it is recognized that the incidence of postoperative hypertension is higher in neurosurgical procedures, mechanisms behind this are not well understood. Oxidative stress is an important component of brain injury, and free radicals can influence blood pressure by a number of mechanisms. This study examined the effect of pretreatment with antihypertensive agents on postoperative hypertension in patients undergoing neurosurgery for supratentorial brain tumors and the role of oxidative stress in the process. METHODS: Forty-nine consecutive patients who underwent surgery for supratentorial brain tumors were divided in to three groups (control, Tab. Glucose; atenolol; and lisinopril groups). Blood was drawn at three time points (1 d before the surgery, at the time of dura opening, and at the time of extubation). Hemodynamic parameters in all three groups and levels of malondialdehyde, protein carbonyl content, nitrate, and α-tocopherol in serum at various time points were analyzed. RESULTS: The results showed that perioperative hemodynamic changes were highly associated with oxidative stress parameters in all the three groups. It was seen that atenolol and lisinopril significantly decreased levels of malondialdehyde, protein carbonyl content, and nitrate in the intraoperative period (P < 0.05), an effect which continued postoperatively. CONCLUSIONS: The results demonstrate that pretreatment with ß-receptor blocker (atenolol) or angiotensin-converting enzyme inhibitor (lisinopril) reduces postoperative hypertension in patients undergoing neurosurgery, and inhibition of oxidative stress may be a potential mechanism for this effect.

Anaesthetic management of a patient with hypokalemic periodic paralysis- a case report.

SUMMARY: We report the anaesthetic management of a patient with hypokalemic periodic paralysis who underwent hepaticojejunostomy for stricture of the common bile duct. Patients with this disorder, who are apparently normal, can develop sudden paralysis as they are exposed to many of the predisposing factors, perioperatively. The complications due to this rare genetic disorder, the factors that can precipitate these problems and preventive measures are discussed.

A comparative study between the effects of 4% endotracheal tube cuff lignocaine and 1.5 mg/kg intravenous lignocaine on coughing and hemodynamics during extubation in neurosurgical patients: a randomized controlled double-blind trial.

A prospective, randomized double-blind trial was performed to compare the effects of 4% endotracheal tube cuff lignocaine and 1.5 mg/kg intravenous (IV) lignocaine on coughing and hemodynamics during extubation in patients undergoing elective craniotomies in supine position. Forty-one patients received 4% lignocaine into the endotracheal tube cuff after intubation (ETT group) and 41 patients received IV lignocaine at 1.5 mg/kg before extubation (IV group). Coughing was assessed by a scale of 3 at the time of extubation. Hemodynamic parameters recorded at 1-minute interval after extubation for 5 minutes were compared with the baseline values recorded before skin closure. Results showed that there was no significant difference between the groups in terms of coughing or the hemodynamic response to tracheal extubation. In conclusion, 4% endotracheal tube cuff lignocaine was not superior to 1.5 mg/kg IV lignocaine in attenuating coughing and hemodynamic changes during extubation.

CT-guided lung biopsies in children: anesthesia management and complications.

We describe the anesthetic management of three children who underwent CT-guided lung biopsies and the complications associated with the procedure. We discuss the likely causes and recommend steps that would help decrease the risk of these complications during such a procedure.

A simple glucose insulin regimen for perioperative blood glucose control: the Vellore regimen.

In this study, we sought a simple, easily implemented method of intraoperative control of blood glucose in diabetic patients in a large multispecialty teaching hospital. The Vellore regimen, which offers the advantages of a combined glucose insulin and variable rate infusion was evaluated. For every 1 to 50-mg/dL increase in blood glucose concentration more than 100 mg/dL, 1 U of insulin was added to the injection port of a 100-mL measured volume set containing 5% dextrose in water. Hourly monitoring of blood glucose was performed. The blood glucose control was compared with the different existing techniques followed in the hospital in 204 randomized patients: 98 in the study and 106 in the control group. The study group had a mean +/- sd blood glucose value of 156 +/- 36 mg/dL, and the control group's value was 189 +/- 63 mg/dL (P = 0.003). The percentage of patients who were poorly controlled (outside 100 to 200-mg/dL range) decreased from 51% to 28% (no patient less than 60 mg/dL) with this regimen as compared with the control group in which it increased from 49% to 72% (10 patients less than 60 mg/dL) (P = 0.0013). We conclude that the Vellore regimen is simple, effective, and safe for intraoperative blood glucose control.