Ashish Bindra

Comparison of the effects of different anesthetic techniques on electrocorticography in patients undergoing epilepsy surgery – A bispectral index guided study

AIM It is well known that general anesthetics suppress/alter electrocorticography (ECoG) activity. However there are no randomized studies available, comparing various anesthetic techniques as regards their effects on ECoG. METHODS The following is a double blind, randomized cross over study to compare the effects of isoflurane and propofol with or without nitrous oxide on electrocorticographic activity in patients undergoing epilepsy surgery. 40 patients suffering from medically intractable epilepsy scheduled to undergo resective surgery under ECoG guidance under general anesthesia, (March 2008-December 2010) were enrolled. Patients received either isoflurane or propofol (with air/oxygen or nitrous oxide/oxygen) as maintenance agents as per randomization and ECoG was recorded and quantified as per a scoring system (range 1-5, where 5 is most abnormal). RESULTS The mean ECoG score in isoflurane group and propofol with nitrous oxide was 3.0(1.2), 3.2(1.2) [p=0.7] and with air was 3.9(1.0) and 3.4(1.1) [p=0.1] respectively. In both isoflurane group and propofol group addition of nitrous oxide depressed the ECoG score (p ≤ 0.01, 0.5 respectively). The total duration of anesthesia, surgery, emergence time, extubation time, and hospital stay was comparable in two groups. CONCLUSION In our study optimal ECoG recordings were possible with use of either isoflurane or propofol. Addition of nitrous oxide to either of the anesthetic regimens suppressed the ECoG score.

Predicting difficult laryngoscopy in acromegalic patients undergoing surgery for excision of pituitary tumors: A comparison of extended Mallampati score with modified Mallampati classification

Background: There are numerous reports of difficult laryngoscopy and intubation in patients with acromegaly. To date, no study has assessed the application of extended Mallampati score (EMS) for predicting difficult intubation in acromegalics. The primary aim of this study was to compare EMS with modified Mallampati classification (MMP) in predicting difficult laryngoscopy in acromegalic patients. We hypothesized that since EMS has been reported to be more specific and better predictor than MMP, it may be superior to the MMP to predict difficult laryngoscopy in acromegalic patients. Materials and Methods: For this prospective cohort study with matched controls, acromegalic patients scheduled to undergo pituitary surgery over a period of 3 years (January 2008-December 2010) were enrolled. Preoperative airway assessment was performed by experienced anesthesiologists and involved a MMP and the EMS. Under anesthesia, laryngoscopic view was assessed using Cormack-Lehane (CL) grading. MMP and CL grades of I and II were defined “easy” and III and IV as “difficult”. EMS grade of I and II were defined “easy” and III as “difficult”. Data were used to determine the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of MMP and EMS in predicting difficult laryngoscopy. Results: Seventy eight patients participated in the study (39 patients in each group). Both MMP and EMS failed to detect difficult laryngoscopy in seven patients. Only one laryngoscopy was predicted to be difficult by both tests which was in fact, difficult. Conclusion: We found that addition of neck extension did not improve the predictive value of MMP.

Stellate ganglion block for relieving vasospasms after coil embolization of basilar tip aneurysms.

To JNA Readers: Cerebral vasospasm is a major cause of disability and death in patients suffering from subarachnoid hemorrhage. Cervical sympathetic and stellate ganglion blocks (SGB) have been described to relieve vasospasm in anterior circulation. We report a case of a basilar tip aneurysm in which the patient developed right-sided hemiparesis after endovascular coiling. A 50-year-old man weighing 65 kg was admitted with complaints of severe headache, giddiness, and vomiting. The Glasgow coma score at admission was E4M6V5. His general physical examination was unremarkable, except for the presence of neck rigidity. His noncontrast computed tomographic (CT) scan revealed blood in the interpeduncular cistern. A diagnosis of subarachnoid hemorrhage Hunt and Hess grade II was made. On digital substraction angiography, a large basilar tip aneurysm measuring 7 6.6mm with a neck of 4.9mm was seen. Endovascular coiling under general anesthesia was planned. A 4 2 cm solitaire was deployed across the neck of the aneurysm crossing the left posterior cerebral artery up to its base. It was released without detaching. Another microcatheter was used to coil the aneurysm. During control angiogram, a thrombus starting from the upper basilar and left proximal posterior cerebral artery was seen. The thrombus was lysed with alteplase (4mg), but aneurysmal leak was noted. Protamine sulfate was given to neutralize the heparin effect, and bleeding stopped. The stent was recaptured and released. A check angiogram revealed basilar tip, bilateral posterior cerebral arteries filling normally. Dynamic CT showed mild subarachnoid hemorrhage with blood in the third and lateral ventricle. The patient was treated conservatively in the intensive care unit. On the third postprocedural day, the CT scan was normal, but the patient developed right-sided weakness. The development of this delayed neurological deficit was attributed to a vasospasm. However, transcranial Doppler (TCD) revealed normal velocities. The patient received intrathecal papaverine (20mg) twice a day and nimodipine (60mg) every 6 hours for 2 days, but no clinical improvement was noticed. On the basis of our previous experience we administered a SGB to the patient opposite to the side of the neurological deficit twice a day for 5 days. There was gradual improvement in limb weakness over this time, and the patient was discharged on day 15 with no residual deficits. Cervical sympathectomy obtained either through a cervical sympathetic block or a SGB has been shown to help patients with an evidence of vasospasm. The SGB has been shown to produce decreases in zero flow pressure, which is a surrogate marker of cerebral vascular tone as evaluated by TCD. The use of SGB has been shown to be of help in patients with anterior circulation aneurysms with TCD evidence of vasospasms. However, this is the first case report of utilization of this technique in a basilar tip aneurysm with delayed ischemic neurological deficit without demonstration of increased flow velocity on TCD examination. The predictive value of TCD has been well described to diagnose vasospasms in the middle cerebral artery. However, the relationship between TCD abnormalities and clinical worsening is unreliable for other vessels. SGB as an adjunct to standard treatment may be beneficial to reverse delayed ischemic neurological deficit due to vasospasms; however, there is a lack of randomized control trial.

Acute hemodynamic instability during alcohol ablation of symptomatic vertebral hemangioma: A prospective study

Symptomatic vertebral hemangiomas (SVH) are difficult to treat and many therapeutic options, including surgery, radiotherapy, arterial embolization, and injection of methyl-methacrylate into hemagiomatous vertebrae have been reported. Alcohol ablation of vertebral hemangiomas is an effective management option; however, a literature search did not reveal any reports of anesthetic complications or hemodynamic instability during and report a series of four males and seven females and report hemodynamic variations observed at the time of injection of absolute ethanol under general anesthetic, for the treatment of SVH. The median age of the patients was 20 years (range, 10-36 years), and median weight was 45 kg (range, 30-70 kg). All patients developed transient hypotension and bradycardia at the time of alcohol injection (8-10 mL of absolute alcohol). No patient required intervention with vagolytics or vasopressors. It is likely that the administration of alcohol in small aliquots prevented any major consequences. Moreover, patients under general anesthesia are at lower risk than those receiving monitored sedation, with better control over hemodynamics.

Causes of tracheal re-intubation after craniotomy: A prospective study

Background: Re-intubation of neurosurgical patients after a successful tracheal extubation in the operating room is not uncommon. However, no prospective study has ever addressed this concern. This study was aimed at analyzing various risk factors of re-intubation and its effect on patient outcome. Methods: Patients aged between 18-60 yrs and of ASA physical status I and II undergoing elective craniotomies over a period of two yrs were included. A standard anesthetic technique using propofol, fentanyl, rocuronium, and isoflurane/sevoflurane was followed, in all these patients. ‘Re-intubation’ was defined as the necessity of tracheal intubation within 72 hrs of a planned extubation. Data were collected and analyzed employing standard statistical methods. Results: One thousand eight hundred and fifty patients underwent elective craniotomy, of which 920 were included in this study. A total of 45 (4.9%) patients required re-intubation. Mean anesthesia duration and time of re-intubation were 6.3±1.8 and 24.6±21.9 hrs, respectively. The causes of re-intubation were neurological deterioration (55.6%), respiratory distress (22.2%), unmanageable respiratory secretion (13.3%), and seizures (8.9%). The most common post-operative radiological (CT scan) finding was residual tumor and edema (68.9%). Seventy-three percent of the re-intubated patients had satisfactory post-operative cough-reflex. The ICU and hospital stay, and Glasgow outcome scale at discharge were not significantly affected by different causes of re-intubation. Conclusion: Neurological deterioration is the most common cause of re-intubation following elective craniotomies owing to residual tumor and surrounding edema. A satisfactory cough reflex may not prevent subsequent re-intubation in post-craniotomy patients.

Anaphylactic reaction after autologous blood transfusion: A case report and review of the literature.

Autologous blood transfusion as a cause of intraoperative anaphylaxis is very rare. We encountered one such life-threatening event in a 72-year-old patient undergoing laminectomy and pedicle screw fixation. The probable cause identified was the floseal mixed autologous blood transfusion. Review of literature has been done, and measures to avoid such an event in the future are discussed.

Management of aspirated tooth in an adult head injury patient: Report of two cases

Aspiration of foreign bodies is common in a pediatric age group but adults can also be at risk. We describe management of two adult trauma victims with aspirated tooth. In the first case, foreign body went missing for sometime by intensive care physician and detected by radiologist while it was obvious in the second case. Both the patients were managed with the help of rigid bronchoscopy. Tooth should be removed as soon as possible or it may result in complete airway obstruction or lung collapse.

Anesthetic management of craniosynostosis repair in patient with Apert syndrome

Apert syndrome is an autosomal dominant disease characterized by craniosynostosis, midface hypoplasia and syndactyly. In general, patients present in early childhood for craniofacial reconstruction surgery. Anesthetic implications include difficult airway, airway hyper-reactivity; however, possibility of raised intracranial pressure especially when operating for craniosynostosis and associated congenital heart disease should not be ignored. Most of the cases described in literature talk of management of syndactyly. We describe the successful anesthetic management of a patient of Aperts syndrome with craniosynostosis posted for bicornual strip craniotomy and fronto-orbital advancement in a 5-year-old child.

Neurogenic pulmonary edema after rupture of intracranial aneurysm during endovascular coiling

Neurogenic pulmonary edema (NPE) is a well-known entity, occurs after acute severe insult to the central nervous system. It has been described in relation to different clinical scenario. However, NPE has rarely been mentioned after endovascular coiling of intracranial aneurysms. Here, we report the clinical course of a patient who developed NPE after aneurysmal rupture during endovascular surgery. There was significant cardiovascular instability possibly from stimulation of hypothalamus adjacent to the site of aneurysm. This case highlights the predisposition of minimally invasive procedures like endovascular coiling to life-threatening complications such as NPE.

Anaesthetic management in patients with glucose-6-phosphate dehydrogenase deficiency undergoing neurosurgical procedures

Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency is an X-linked recessive enzymopathy responsible for acute haemolysis following exposure to oxidative stress. Drugs which induce haemolysis in these patients are often used in anaesthesia and perioperative pain management. Neurosurgery and few drugs routinely used during these procedures are known to cause stress situations. Associated infection and certain foodstuffs are also responsible for oxidative stress. Here, we present two patients with G-6-PD deficiency who underwent uneventful neurosurgical procedures. The anaesthetic management in such patients should focus on avoiding the drugs implicated in haemolysis, reducing the surgical stress with adequate analgesia, and monitoring for and treating the haemolysis, should it occur.