Virendra Jain

A randomized, double-blinded comparison of ondansetron, granisetron, and placebo for prevention of postoperative nausea and vomiting after supratentorial craniotomy.

Postoperative nausea and vomiting (PONV) are frequent and distressing complications after neurosurgical procedures. We evaluated the efficacy of ondansetron and granisetron to prevent PONV after supratentorial craniotomy. In a randomized double-blind, placebo controlled trial, 90 adult American Society of Anesthesiologists I, II patients were included in the study. A standard anesthesia technique was followed. Patients were divided into 3 groups to receive either placebo (saline), ondansetron 4 mg, or granisetron 1 mg intravenously at the time of dural closure. After extubation, episodes of nausea and vomiting were noted for 24 hours postoperatively. Statistical analysis was performed using χ2 test and 1-way analysis of variance. Demographic data, duration of surgery, intraoperative fluids and analgesic requirement, and postoperative pain (visual analog scale) scores were comparable in all 3 groups. It was observed that the incidence of vomiting in 24 hours, severe emetic episodes, and requirement of rescue antiemetics were less in ondansetron and granisetron groups as compared with placebo (P<0.001). Both the study drugs had comparable effect on vomiting. However, the incidence of nausea was comparable in all 3 groups (P=0.46). A favorable influence on the patient satisfaction scores, and number needed to prevent emesis was seen in the 2 drug groups. No significant correlation was found between neurosurgical factors (presence of midline shift, mass effect, pathologic diagnosis of tumor, site of tumor) and the occurrence of PONV. We conclude that ondansetron 4 mg and granisetron 1 mg are comparably effective at preventing emesis after supratentorial craniotomy. However, neither drugs prevented nausea effectively.

Stellate ganglion block for treatment of cerebral vasospasm in patients with aneurysmal subarachnoid hemorrhage - A preliminary study.

Background: Stellate ganglion block improves cerebral perfusion by decreasing the cerebral vascular tone. Its effects on cerebral vasospasm to relieve neurological deficits have not been evaluated. This prospective observational study was carried out to evaluate the effect of stellate ganglion block on cerebral hemodynamics in patients with symptomatic cerebral vasospasm following aneurysmal subarachnoid hemorrhage. Materials and Methods: Fifteen patients of either sex, aged 18-75 years, who underwent surgical clipping of aneurysm and developed refractory cerebral vasospasm were included. Stellate ganglion block was performed using 10 ml of bupivacaine 0.5% on the side with maximum cerebral blood flow velocity. Neurological status, cerebral blood flow velocity and pulsatility index were assessed before and 10 minutes, 30 minutes, 2 hours, 6 hours, 12 hours and 24 hours after stellate ganglion block. Results: Improved Glasgow coma score was observed 30 minutes after stellate ganglion block. Neurological deficits reduced in 11 patients. Ipsilateral middle cerebral artery mean flow velocity decreased from 133.66 cm/sec before stellate ganglion block to 110.53 cm/sec at 6 hours (P<0.001) and 121.62 cm/sec at 24 hours (P<0.001) after stellate ganglion block. There was a decrease in ipsilateral anterior cerebral artery mean flow velocity after stellate ganglion block (P<0.001), which persisted for 12 hours. A decline in flow velocities was observed in contralateral middle cerebral artery (P=0.008) and anterior cerebral artery (P=0.041) for 12 hours. Conclusion: This study suggests stellate ganglion block to be an effective modality of treatment for refractory cerebral vasospasm after aneurysmal subarachnoid hemorrhage.

Metformin-associated lactic acidosis following contrast media-induced nephrotoxicity

Metformin-associated lactic acidosis following contrast media-induced nephrotoxicity V. Jain;D. Sharma;H. Prabhakar;H. Dash; European Journal of Anaesthesiology

Tension pneumocephalus following deep brain stimulation surgery with bispectral index monitoring.

© 2006 Copyright European Society of Anaesthesiology, European Journal of Anaesthesiology 24: 198–207 EDITOR: Deep brain stimulation (DBS) is increasingly being used for treatment of movement disorders associated with Parkinson’s disease (PD). The procedure involves functional lesioning of subthalamic nucleus (STN) and globus pallidus internus (GPI) after placement of stimulator leads via burr hole craniotomies. The procedure is usually performed under monitored anaesthesia care with minimal or no sedation. During these procedures we use bispectral index (BIS) monitoring regularly along with the routine monitors because it may reflect the hypnotic effect of anaesthetics and sedative drugs. Various complications have been reported associated with DBS surgery [1] although tension pneumocephalus has never been reported. We report a case where a patient undergoing DBS surgery developed tension pneumocephalus associated with lowering of BIS value intraoperatively. A 63-yr-old male weighing 58 kg was scheduled for magnetic resonance imaging guided, stereotactic frame based bilateral placement of electrodes for DBS. His past medical history was significant for coronary artery disease 6 yr previously. A 2-D echocardiogram showed concentric left ventricular hypertrophy with mild aortic regurgitation along with a left ventricular ejection fraction of 45%. The patient was kept fasting overnight. The first part of the procedure, that is electrode placement, was done under monitored anaesthesia care. In the operating theatre intravenous access was secured using an 18-G cannula on the dorsum of the left hand. Monitoring included 5-lead ECG, noninvasive blood pressure, pulse oximetry, and A-2000 BIS monitor (Aspect Medical Systems, Newton). The BIS sensor was placed on the right side of the forehead. Supplemental O2 was administered via nasal prongs at a flow rate of 2 L min 1. The patient was positioned supine on the operating table in a stereotactic frame with 10° head up tilt. At the initiation of surgery, the heart rate and blood pressure were 64 beats min 1 and 130/56 mmHg, respectively and BIS was 98. After local anaesthetic infiltration, burr holes were made bilaterally. Electrodes were placed on both the subthalamic nuclei. The patient’s responses to the test stimulation as assessed by the neurologist were satisfactory. This part of procedure lasted approximately 5 h. It was then noticed that the patient had became drowsy but was still obeying to verbal commands. The BIS monitor showed a value of 75–85. The second part of the DBS surgery was placement of a battery in the anterior chest wall for further regulation of the stimulations. This was performed under general anaesthesia. General anaesthesia was induced with fentanyl 2 μg kg 1 and thiopentone 200 mg intravenously. Tracheal intubation was facilitated with rocuronium 60 mg intravenously. Anaesthesia was maintained with isoflurane in a mixture of O2 and N2O (1:2). BIS was maintained at 40–60. The procedure was completed uneventfully in 30 min. At the end of the procedure the patient was reversed from residual neuromuscular blockade with neostigmine and glycopyrrolate. As the patient was maintaining adequate tidal volume and responding to verbal commands, though drowsy, the trachea was extubated. After 15 min, he was still drowsy with a BIS of 65–75. Oxygen was given by facemask and the patient was transferred to the intensive care unit (ICU). The drowsiness persisted even after 1 h in the ICU so a computed tomographic (CT) scan was performed which revealed a tension pneumocephalus (Fig. 1). As the patient was haemodynamically stable with no lateralizing signs, no active intervention was considered except close monitoring. BIS was continuously monitored in the postoperative period. For the initial 10 h after surgery, BIS remained in the range 65–80. Later, it started to rise gradually coinciding with improving conscious level. The patient was moved to the postoperative ward after 18 h fully orientated and with a BIS value of 98. A CT scan 18 h after surgery showed a complete resolution of the pneumocephalus. Pneumocephalus has been known to occur after any craniotomy procedure with an incidence reported to be 100% following supratentorial craniotomies [2]. Generally it is asymptomatic but occasionally high pressure may build up in the air cavity with development of tension pneumocephalus. Although tension pneumocephalus is more common after posterior fossa or cervical spine surgery in the sitting position, it is rare following the supine position. It may manifest as deterioration of consciousness with or without lateralizing signs, severe restlessness, generalized Tension pneumocephalus following deep brain stimulation surgery with bispectral index monitoring

Does egress of cerebrospinal fluid during percutaneous retrogasserian glycerol rhizotomy influence long term pain relief

Background and Objectives: To examine the effect of cerebrospinal fluid (CSF) flow during percutaneous retrogasserian glycerol rhizotomy (PRGR) on long term pain relief in patients with trigeminal neuralgia. Methods: Eighty‐nine patients with trigeminal neuralgia underwent 102 PRGR procedures. PRGR was conducted under fluoroscopy. After the egress of CSF, anhydrous glycerol (0.3‐0.4 cc) was injected in the sitting position. In the absence of CSF flow, 0.25 mL 2% lidocaine was injected to elicit hypesthesia in the affected side. Once hypesthesia was elicited glycerol was injected. Patients were grouped as A (CSF flow present) or B (CSF flow absent), according to the egress of CSF at the time of needle placement. Patients were followed up for the recurrence of pain (average duration of follow up, 62 months). Results: CSF flow was present in 54 patients (60.6%) and absent in 35 patients (39.4%). Thirty patients (56.6%) of group A had excellent pain relief, 18 patients (33.3%) had good pain relief, and 6 patients (11.1%) had no pain relief. However, in the absence of CSF flow, 14 patients (40%) each had excellent and good pain relief, and 7 patients (20%) were treatment failures. The pain relief was comparable between the groups. The median time to recurrence of pain needing further injection was 66 months in group A and 63 months in group B (not significant). Conclusions: Presence of CSF flow during needle placement does not influence the success rate and duration of pain relief following PRGR.

Morbidly obese patient with obstructive sleep apnoea for major spine surgery: An anaesthetic challenge.

Morbidly obese patients with clinical features of obstructive sleep apnoea can present a myriad of challenges to the anaesthesiologists which must be addressed to minimise the perioperative risks. Initiation of continuous positive airway pressure (CPAP) therapy early in the pre- and post-operative period along with appropriate anaesthetic planning is of paramount importance in such patients. This case report emphasises the usefulness of CPAP therapy, even for a short duration, to minimise morbidity, improve recovery and hasten early discharge from the hospital after major surgery.

An unusual case of hypoplastic internal jugular vein in a vein of Galen malformation

Vein of Galen malformations (VOGMs) are rare anomalies of intracranial circulation that constitute 1% of all intracranial vascular malformations. However, they represent 30% of vascular malformations presenting in the paediatric age group.[1] These lesions are characterised by the presence of an aneurysmally dilated midline deep venous structure, fed by abnormal arteriovenous communications. The venous system of the brain is mal-developed many venous anomalies can associate with VOGM. We describe a case of VOGM in which there was hypoplasia of the right internal jugular vein (IJV) leading to failure in the placement of central venous catheter through right IJV.

Near-infrared spectroscopy

Tissue ischaemia can be a significant contributor to increased morbidity and mortality. Conventional oxygenation monitoring modalities measure systemic oxygenation, but regional tissue oxygenation is not monitored. Near-infrared spectroscopy (NIRS) is a non-invasive monitor for measuring regional oxygen saturation which provides real-time information. There has been increased interest in the clinical application of NIRS following numerous studies that show improved outcome in various clinical situations especially cardiac surgery. Its use has shown improved neurological outcome and decreased postoperative stay in cardiac surgery. Its usefulness has been investigated in various high risk surgeries such as carotid endarterectomy, thoracic surgeries, paediatric population and has shown promising results. There is however, limited data supporting its role in neurosurgical population. We strongly feel, it might play a key role in future. It has significant advantages over other neuromonitoring modalities, but more technological advances are needed before it can be used more widely into clinical practice.