Unilateral External Anal Sphincter MEP Monitoring in a Case of Conus Medullaris Tumor.

The use of intraoperative neurophysiological monitoring is a helpful tool during surgeries of conus medullaris tumors and helps in reducing the risk of post-operative functional compromise like paraparesis, sensory deficits, or urological dysfunctions. External anal sphincter (EAS) motor evoked potential (MEP) monitoring is usually done for monitoring sacral nerve roots and to prevent post-operative neurological deficits. Here we describe a case where unilateral motor cortical stimulation aided us to differentiate the laterality of TcMEP responses in EAS.

Intraoperative neurophysiological monitoring in paediatric neurosurgery.

Intraoperative neurophysiological monitoring (IONM) is commonly used in various surgical procedures in adults, but with technological and anaesthetic advancements, its use has extended to the paediatric population. The use of IONM in children poses a unique set of challenges considering the anatomical and physiological differences in this group of patients. The use of IONM aids in the localization of neural structures and enables surgeons to preserve the functional neural structures leading to decreased incidence of postoperative neurological deficits and better patient outcomes. In this article, we review the use of IONM in paediatric patients undergoing various spinal and cranial neurosurgical procedures. We discuss the patient characteristics, type of surgeries, and technical and anaesthetic considerations about IONM in this population.

Anaesthetic management of a case of Haberland's syndrome (encephalocraniocutaneous lipomatosis).

While the Haberland syndrome was first reported in 1970, the anaesthetic management of this rare cohort of patients has not been described. With only 54 such cases reported, describing primarily the unilateral cutaneous, ocular, and neurologic malformations associated with this syndrome without focussing on the anaesthetic management. We describe the case of a 7 year old case of Harberland syndrome with special focus on the difficulties faced by us in mask ventilation, as well as intubation and the need for elective ventilation and planned extubation. We also discuss the precautions to be taken while undertaking such a case like preparations for emergency tracheostomy and possibility of re-intubation after extubation. A meticulous preoperative workup along with neurological and airway examination along with preparation for elective ventilation and tracheostomy is a prerequisite for the successful management of this case.

Haemodynamic changes during prone positioning in anaesthetised chronic cervical myelopathy patients.

BACKGROUND AND AIMS: Anaesthetised patients, when positioned prone, experience hypotension and reduction in cardiac output. Associated autonomic dysfunction in cervical myelopathy patients predisposes them to haemodynamic changes. The combined effect of prone positioning and autonomic dysfunction in anaesthetised patients remains unknown. METHODS: Thirty adult chronic cervical myelopathy patients, aged 18-65 years with Nurick grade ≥2 were recruited in this prospective observational study. Heart rate, mean blood pressure, cardiac output, stroke volume, total peripheral resistance and stroke volume variation were measured using NICOM® monitor. Data were collected in supine before anaesthetic induction (baseline), 2 minutes after induction, 2 minutes after intubation, before and after prone positioning and every 5 minutes thereafter until skin incision. Repeated measures analysis of variance (ANOVA) was used to analyse the haemodynamic parameters across the time points. Bivariate Spearman's correlation was used to find factors associated with blood pressure changes. A P value <0.05 was kept significant. RESULTS: Cardiac output during the entire study period remained stable (P = 0.186). Sixty percent of the patients experienced hypotension. At 15 and 20 minutes after prone positioning, mean blood pressure decreased (P = 0.001), stroke volume increased (P = 0.001), and heart rate and total peripheral resistance decreased (P < 0.001, P = 0.001, respectively). These changes were significant when compared to pre-prone position values. Number of levels of spinal cord compression positively correlated with the incidence of hypotension. CONCLUSION: Cervical myelopathy patients experienced hypotension with preserved cardiac output in prone position due to a reduction in total peripheral resistance. Hypotension correlated with the number of levels of spinal cord compression.

A Comparative Study of Midazolam and Target-Controlled Propofol Infusion in the Treatment of Refractory Status Epilepticus.

BACKGROUND: The recommended treatment for refractory status epilepticus (RSE) is the use of anesthetic agents, but evidence regarding the agent of choice is lacking. This study was designed to compare target-controlled infusion of propofol versus midazolam for the treatment of RSE regarding seizure control and complications. METHODS: This prospective, randomized study recruited 23 adult patients with RSE due to any etiology and treated with either propofol or midazolam titrated to clinical seizure cessation and gradual tapering thereafter. The primary outcome measure was seizure control and the secondary outcomes were duration of the Intensive Care Unit stay and duration of mechanical ventilation, occurrence of super RSE (SRSE), and complications. RESULTS: We recruited 23 patients (male:female = 18:5) into this study (propofol Group-11; midazolam Group-12). Overall, seizure control was noted in 34.8%, with successful seizure control in 45% of patients in the propofol group and 25% in midazolam group (P = 0.4). Mortality was similar in both the groups (propofol group [8/11; 72.7%] compared to the midazolam group [7/12; 58.3%] [P = 0.667]). The duration of hospital stay was significantly shorter in the propofol group compared to midazolam (P = 0.02). The overall incidence of SRSE was 69.5% in this study. The complication rate was not significantly different between the groups. CONCLUSIONS: The choice of anesthetic agent does not seem to affect the overall outcome in RSE and SRSE. Target-controlled propofol infusion was found to be equal in its efficacy to midazolam for the treatment of RSE. High mortality might be due to SRSE secondary to the underlying brain pathology.

Effect of adjunctive dexmedetomidine on anesthesia and analgesia requirement and recovery characteristics during Bispectral Index-guided anesthesia for cerebello-pontine angle surgeries: A randomized clinical trial.

BACKGROUND AND AIMS: The study was conceived to elucidate the effects of dexmedetomidine as an anesthetic adjunct to propofol (total intravenous anesthesia) on anesthetic dose reduction and anesthesia recovery parameters in cerebello-pontine angle (CPA) surgeries. MATERIAL AND METHODS: This prospective randomized study was conducted on 49 patients (25 with dexmedetomidine, 24 without). After standardized anesthetic induction, anesthesia was maintained using propofol (via target controlled infusion, titrated to maintain BIS between 40 and 60), fentanyl (0.5 µg/kg/hour) and either dexmedetomidine (0.5 µg/kg/hour) or a sham infusion. Neuromuscular blocking agents were excluded to allow cranial nerve EMG monitoring. Adverse hemodynamic events, recovery parameters (time to opening eyes, obeying commands, and extubation) and postoperative sedation score, shivering score, nausea, and vomiting score were recorded. RESULTS: Propofol and fentanyl utilization (as total dose, adjusted for duration of surgery and body weight, and number of extra boluses) was significantly lower in the dexmedetomidine group. There was no difference in any of the recovery parameters between the two groups. Incidence of bradycardia was significantly higher with dexmedetomidine, while no difference was found for hypotension, hypertension, and tachycardia. CONCLUSION: Dexmedetomidine-fentanyl-propofol anesthesia compares favorably with fentanyl-propofol anesthesia during CPA neurosurgical procedures with regard to anesthesia recovery times, but with lower intraoperative opioid and hypnotic utilization rates.

Airway Management in an Infant With Huge Hydrocephalus.

Huge hydrocephalus is defined as a head circumference larger than the length of the child. We discuss the perioperative anesthetic management of a case of huge hydrocephalus during ventriculoperitoneal shunt placement, focusing primarily on the airway management. The patient was a 4-month-old with a midline supratentorial lesion causing obstructive hydrocephalus due to compression of the sylvian aqueduct. For optimum positioning for direct laryngoscopy, a pillow was placed below the baby's torso, to achieve a slight extension at the atlantoaxial joint. This maneuver decreased the angle between the line of vision and the laryngeal axis (calculated from the images), which effectively improved alignment.

Ventilatory Management During Intraoperative Airway Obstruction due to Endotracheal Tube Kinking.

We present a case of polyvinyl chloride (PVC) endotracheal (ET) tube kinking and discuss the airway pressure changes, implications, and ventilation-based methods to functionally remedy the situation. The kink developed in the intraoral portion of an 8.5-cm PVC ET tube in a patient undergoing T3-T5 laminectomy in the prone position, heralded by a sudden increase in peak airway pressure. The kink was confirmed by attempted intratubal suction. Adequate ventilation was achieved with conversion to pressure control (PC) mode with an inspiratory-expiratory time (I:E) ratio of 1:1. An experiment was conducted using 8.5-cm PVC ET tube, ventilating a 2-L reservoir bag. A kink was artificially created on the ET tube and ventilated with volume control (VC) and then PC mode. Both modes delivered equal tidal volumes at equal plateau pressures, with higher peak pressures in VC mode. The PC mode with I:E 1:1 delivered higher tidal volume than I:E 1:2 and 2:1 at equal plateau pressures. Whereas previous reports of intraoperative ET tube kinking discussed the detection, diagnosis, cause, and management in scenarios where the tube is readily accessible, we highlight airway pressure characteristics and ventilator management of such a situation when an ET tube was not amenable to remedial solutions.