Transcranial ultrasonographic evaluation of effect of ventriculoperitoneal shunt on intracranial dynamics: A prospective observational study.

BACKGROUND: Transcranial sonographic (TCS) evaluation of optic nerve sheath diameter (ONSD), third ventricular diameter (TVD) and mean flow velocities (Vm) and pulsatility index (PI) of middle cerebral artery (MCA) can provide important insights to the change in intracranial dynamics following ventriculo-peritoneal (VP) shunt surgery. The primary objective of this study was to observe changes in ONSD values following VP shunt at 12 h, compared to pre-VP shunt values. METHODS: After obtaining ethical approval, patients admitted with a diagnosis of hydrocephalus posted for a VP shunt surgery were prospectively enrolled. TCS evaluation was done before induction of anesthesia and 12-hour post-VP shunt surgery. We recorded the values of ONSD, TVD and Vm and PI MCA at both time points. RESULTS: Thirty-four patients (19 male) were evaluated for ONSD and for the improvement of symptoms. Transtemporal window could not be obtained in six patients. At 12 h following VP shunt, bilateral median ONSD values reduced significantly from their pre-VP shunt values [right ONSD- 0.62 (0.59-0.64) to 0.53 (0.5-0.54) mm (p < 0.001); left ONSD- 0.62 (0.59-0.63) to 0.53 (0.5-0.54) mm (p < 0.001)]. Similarly, the median TVD at 12 h post-VP shunt reduced significantly from its pre-VP shunt measurements [0.97 (0.85-1.09) to 0.74 (0.7-0.84) cm]. PI MCA values reduced significantly, while Vm MCA values increased significantly from the pre-VP shunt values. CONCLUSION: VP shunt reduced the ONSD, TVD, PI MCA and increased the Vm MCA after shunt surgery as early as 12hrs.

Postoperative delayed neurocognitive recovery: Evaluation of its incidence and correlation with intraoperative cerebral desaturation - A prospective observational study.

BACKGROUND: Delayed neurocognitive recovery (DNR) is commonly seen in patients in the postoperative period. Literature has shown that monitoring cerebral desaturation intraoperatively can predict the development of DNR in elderly patients undergoing surgery in prone position. This prospective observational study was conducted in patients of all ages, with the primary objective to determine the incidence of DNR and its correlation with cerebral oximetry. The secondary objectives were to determine if intraoperative cerebral desaturation influenced the neuropsychometric variables from preoperative to postoperative period. METHODS: This study included 61 patients, aged > 18 years undergoing spinal surgery in prone position. An evening before surgery and at 48 h postoperatively, patients were subjected to neuropsychological examination; Hindi Mental State Examination, Colour Trail Test 1 (CTT 1), CTT 2, Auditory Verbal Learning (AVLT) tests conducted by principal investigator (PI). DNR was defined as a 20% change in any of the test scores from the baseline. rSO2 was recorded bilaterally every 10 min throughout surgery by an independent person. Cerebral desaturation was defined as a 20% drop in rSO2 from the control value. RESULTS: The incidence of DNR was 24.6%. The duration of anesthesia and cerebral desaturation were found to be independently predictive of DNR, with each hour of anesthesia causing a two-fold increase in the chances of development DNR (P = 0.019) and presence of cerebral desaturation causing a 6-fold increase (P = 0.039). CTT 1 and CTT 2 tests had significantly larger increase in test scores in the postoperative period, in patients with cerebral desaturation. CONCLUSION: Duration of anesthesia and cerebral desaturation were factors predictive of the development of DNR in patients undergoing spine surgery in prone position.

Cervical Spine Movement During Awake Orotracheal Intubation With Fiberoptic Scope and McGrath Videolaryngoscope in Patients Undergoing Surgery for Cervical Spine Instability: A Randomized Control Trial.

BACKGROUND: Cervical spine movement during intubation with direct laryngoscopy can predispose to new-onset neurological deficits in patients with cervical spine instability. While fiberoptic-guided intubation (FGI) is mostly preferred in such patients, this is not always possible. Videolaryngoscopy results in less cervical spine movement than direct laryngoscopy and may be an alternative to FGI in patients with cervical spine instability. The objective of this study was to compare cervical spine movement during awake FGI with those during awake McGrath videolaryngoscope-guided intubation (VGI) in patients undergoing surgery for cervical spine instability. METHODS: Forty-six adult patients with upper cervical spine instability scheduled for stabilization surgery were randomized to awake FGI or awake VGI. Cervical spine movement during intubation was assessed by changes in lateral fluoroscopic-measured angles (α and ß at C1/C2 and C3 levels, respectively) at 3 time points: T1, preintubation; T2, during intubation; T3, postintubation. Motor power was assessed before and after intubation. RESULTS: Patient demographics and airway characteristics were similar between the 2 groups. Cervical spine motion (in degrees) during intubation was significantly greater with VGI than FGI at C1/C2 (T3-T1, -8.02±8.11 vs. -1.47±3.31; P<0.001) but not at C3 (T3-T1, -2.17±5.16 vs. -1.85±3.29; P=0.960). No patient developed new-onset motor deficits following intubation in either group. CONCLUSIONS: Compared with FGI, VGI results in a greater degree of cervical spine movement at C1/C2 but not at C3.

Analgesia nociception index and systemic haemodynamics during anaesthetic induction and tracheal intubation: A secondary analysis of a randomised controlled trial.

BACKGROUND AND AIMS: Direct laryngoscopy and tracheal intubation is a noxious stimulation that induces significant stress response. Currently, this nociceptive response is assessed mainly by haemodynamic changes. Recently, analgesia nociception index (ANI) is introduced into anaesthesia practice and provides objective information about parasympathetic (low nociceptive stress) and sympathetic (high nociceptive stress) balance, which reflects the degree of intraoperative nociception/analgesia. This study evaluated the changes in ANI and haemodynamics during anaesthetic induction and intubation, and their correlation during tracheal intubation. METHODS: Sixty adult patients scheduled for elective brain tumour surgery under general anaesthesia were studied for changes in ANI, heart rate (HR) and mean blood pressure (MBP) during anaesthetic induction and intubation. This was a secondary analysis of a previously published trial. Linear mixed effects model was used to evaluate changes in ANI, HR and MBP and to test correlation between ANI and haemodynamics. RESULTS: Anaesthetic induction reduced ANI (but not below the critical threshold of nociception of 50) and MBP, and increased the HR (P < 0.001). Direct laryngoscopy and tracheal intubation resulted in increase in HR and MBP with decrease in ANI below the threshold of 50 (P < 0.001). A linear negative correlation was observed between ANI and HR; r = -0.405, P < 0.001, and ANI and MBP; r = -0.415, P = 0.001. CONCLUSION: Significant changes are observed in ANI during anaesthetic induction and intubation. There is a negative linear correlation between ANI and systemic haemodynamics during intubation.

Comparison of equiosmolar dose of hyperosmolar agents in reducing intracranial pressure-a randomized control study in pediatric traumatic brain injury.

INTRODUCTION: There are no comparative studies available for hyperosmolar therapy in children. The present study is a prospective open label randomized control trial to compare the effect of equiosmolar doses of mannitol and hypertonic saline in reducing intracranial pressure in children who sustained severe traumatic brain injury. METHODS: This is a prospective open-label randomized controlled trial. Thirty children aged less than or equal to 16 years with severe traumatic brain injury and raised intracranial pressure as measured by ventricular catheter insertion were enrolled. Sixteen children received 20% mannitol, and 14 children received 3% saline as 2.5 ml/kg bolus for episodes of intracranial pressure above cutoff value for age. The mean reduction in intracranial pressure and Glasgow outcome scale at 6 months after injury was measured. RESULTS: The mean reduction in intracranial pressure in mannitol group was 7.13 mmHg and in hypertonic saline group was 5.67 mmHg, and the difference was not statistically significant, p = 0.33. The incidence of death or survival in vegetative state was 23.07% in mannitol group and 16.66% in hypertonic saline group, and the difference was not statistically significant, p = 0.69. CONCLUSION: Both mannitol and hypertonic saline were equally effective for treatment of raised intracranial pressure in children with severe traumatic brain injury.

Duration of Pupillary Unresponsiveness to Light: A Physiological Adjunct to Electroencephalography and Motor Seizure Duration Monitoring During Electroconvulsive Therapy.

BACKGROUND: During electroconvulsive therapy (ECT) sessions, we observed that the time taken for the return of pupillary response to light (ROPL) outlasted both the electroencephalography (EEG) and the motor seizure duration after the delivery of the electrical stimulus to produce convulsions. OBJECTIVE: The objective of this study was to investigate whether ROPL can be used as a marker of cessation of seizure activity in the brain after ECT and also to study the effect of atropine premedication on seizure activity during ECT. METHODS: Forty-one patients underwent 82 sessions of ECT in a cross-over design study. The duration of motor seizure, EEG seizure, and time for ROPL was observed and compared. RESULTS: The ROPL consistently outlasted EEG and motor seizures; the difference in their mean durations was statistically significant P < 0.05. There was good correlation among the 3 parameters. Atropine premedication did not alter the seizure activity and ROPL after ECT. CONCLUSIONS: The ROPL after ECT stimulus is a good bedside monitor for termination of seizure activity and can be a valuable adjunct to surface EEG in monitoring the duration of epileptic activity after delivery of ECT.

Comparative study of fiberoptic guided versus intubating laryngeal mask airway assisted awake orotracheal intubation in patients with unstable cervical spine.

BACKGROUND: A safe airway technique minimizes intubation-associated cervical-spine movement and consequent neurological injury in patients with unstable cervical spine (UCS). Awake fiberoptic-guided intubation (FGI) is preferred in patients with UCS. Alternatively, intubating laryngeal mask airway assisted intubation (ILMA-AI) can be performed both during elective and emergency, requires less expertise and is cost-effective. This study evaluated cervical-spine movement during FGI and ILMA-AI in patients with UCS. METHODS: This was a parallel-group randomized controlled trial performed at a tertiary neurosciences hospital. Thirty-two patients with UCS scheduled for corrective surgery were allocated equally to receive FGI or ILMA-AI according to centralized computer-generated randomization. Primary outcome measure was cervical-spine movement as assessed using fluoroscopy at C1/2 level during intubation. Secondary outcomes were movement at C2/3 and new-onset motor deficit after intubation. RESULTS: All the sixteen patients in each group were successfully intubated and their data was analyzed. No significant difference in angles (indicating cervical spine movement) was observed at both C1/2 and C2/3 levels between FGI and ILMA-AI groups at various time points studied (P>0.05). No new-onset motor deficit was observed after intubation in both groups. One patient in FGI group developed desaturation during intubation while four patients in ILMA-AI group developed postoperative sore-throat. CONCLUSIONS: Similar degree of angulations was observed at various time-points during awake FGI and awake ILMA-AI at C1/2 and C2/3 spinal levels in patients with UCS. No patient developed new-onset motor deficits. ILMA can serve as a suitable alternative to fiberoptic-scope for awake intubation in cervical-spine instability.

Use of Dexmedetomidine Along With Local Infiltration Versus General Anesthesia for Burr Hole and Evacuation of Chronic Subdural Hematoma (CSDH).

BACKGROUND: In neurosurgery, chronic subdural hematoma (CSDH) is a very common clinical entity. Both general anesthesia (GA) and local anesthesia with or without sedation are used for the surgical treatment of CSDH. Sedation with dexmedetomidine has been safely used for various diagnostic and therapeutic procedures. However, its effectiveness against GA has not been evaluated for surgical treatment of CSDH. We tried to compare dexmedetomidine sedation technique with the GA technique for surgical treatment of CSDH. MATERIALS AND METHODS: In this prospective-randomized study, 76 patients undergoing surgery for CSDH were divided into 2 groups using computer-generated randomized tables; Dex group ([n=38]; received IV bolus of dexmedetomidine 1 mcg/kg over 10 min followed by maintenance infusion 0.5 mcg/kg/h) and GA group ([n=38; of which 4 patients were dropped out]; received endotracheal intubation with balanced anesthesia). RESULTS: Both anesthesia techniques (Dex group; n=35/38 [92.1%] and GA group; n=34/34 [100%]) were successfully used for surgical treatment of CSDH. Significantly less time for anesthesia onset (14.2±4.2 vs. 20.5±3.4 min, P=0.001), total duration of surgery (77.1±23.9 vs. 102.7± 24.8 min, P=0.001), and recovery from anesthesia (7.4±5.9 vs. 13.2±6.5 min, P=0.004) was observed in the Dex group compared with GA group. Perioperative hemodynamic fluctuations were more common in the GA group as against the Dex group. Postoperative complications (n=2 vs. 9, P=0.021) and length of hospital stay (1.05±0.23 vs. 1.79±2.1 d, P=0.007) were significantly less in the Dex group as against the GA group. CONCLUSIONS: Dexmedetomidine sedation with local anesthesia is a safe and effective technique for burr hole and evacuation of CSDH. It is associated with significantly shorter operative time, lesser hemodynamic fluctuations, postoperative complications, and length of hospital stay, thus it is a better alternative to GA.

Anesthetic factors and outcome in children undergoing indirect revascularization procedure for moyamoya disease: An Indian perspective.

BACKGROUND: Moya Moya disease (MMD) is one of the most common cerebro-vascular diseases in children resulting in stroke. Surgical revascularization aims at improving the perfusion to the 'at-risk' ischemic brain. Several factors including peri-operative anesthetic related ones, affect the outcome in these children. This study was performed with the aim to explore the role of anesthetic techniques, pharmacological agents and perioperative management strategies on the neurological outcome following an indirect revascularization procedure for the treatment of MMD. MATERIALS AND METHODS: This was a retrospective chart review of pediatric indirect revascularization procedures for MMD during a three year period at a tertiary neurosciences hospital in southern India. Demographic details, disease characteristics and variables related to anesthetic management were obtained from the patient's charts and analyzed. The main outcome measure was occurrence of postoperative new neurological complications; and, the secondary outcome was length of hospital stay after surgery. RESULTS: Twenty-two children underwent thirty indirect revascularization procedures, of which four patients had new postoperative neurological complications. One child died due to bilateral cerebral infarcts following bilateral surgery as a single stage under the same anesthesia. Female gender and a higher opioid dose were associated with occurrence of postoperative neurological deficits. Younger age, prolonged anesthetic duration and occurrence of postoperative neurological deficits were associated with prolonged postoperative hospital stay. However, none of these factors were predictive of either an adverse neurological outcome or a prolonged hospital stay. CONCLUSION: In this study, anesthetic techniques or medications did not influence the occurrence of postoperative neurological deficits or prolonged hospital stay after an indirect revascularization procedure in children with MMD.

A comparative study of dexmedetomidine and propofol as sole sedative agents for patients with aneurysmal subarachnoid hemorrhage undergoing diagnostic cerebral angiography.

PURPOSE: Subarachnoid hemorrhage is an acute neurological emergency requiring urgent confirmation of the diagnosis for planning definitive management. Due to altered consciousness, most patients require sedation for conducting this procedure smoothly. Currently, it is unclear if any one particular sedative drug has a favorable profile in patients undergoing cerebral angiography. The aim of this study was to compare the traditionally used sedative drug propofol with a newer alternative, dexmedetomidine, in patients with subarachnoid hemorrhage undergoing cerebral angiography. METHODS: Sixty adult patients with good grade subarachnoid hemorrhage undergoing diagnostic cerebral angiography were prospectively randomized to receive either propofol (n = 30) or dexmedetomidine (n = 30) following ethics committee approval and informed consent. RESULTS: Compared to dexmadetomidine, propofol was associated with an earlier time for onset of sedation (2.3 ± 1.9 min vs. 15.4 ± 5.7 min; P < 0.001), but with an increased number of adverse respiratory events (11/30 vs 1/30; P = 0.003) and movement during the procedure (5/30 vs. 0/30; P = 0.05), necessitating additional supplementation of sedation (13/30 vs. 7/30; P = 0.17) and repetition of the imaging sequences. The total procedure time and time for recovery were similar for the propofol and dexmedetomidine groups, while the heart rate was lower in patients in the dexmedetomidine group. CONCLUSION: Dexmedetomidine appears to be superior to propofol as a sole sedative agent for sedation during cerebral angiography in patients with subarachnoid hemorrhage.

Expansile cranioplasty for massive occipital encephalocele.

OBJECTIVE: This report highlights the management of infrequently encountered massive occipital encephaloceles with herniation of large amount of apparently functional cortex into the encephalocele sac. MATERIALS AND METHODS: Two children with giant occipital encephaloceles with herniation of significant brain parenchyma into the encephalocele sac were managed with expansile cranioplasty and reconstruction of the calvarial defect with autologus bone graft harvested from the adjacent parietal region. CONCLUSIONS: Giant occipital encephaloceles with significant brain parenchyma in the encephalocele sac can be considered for preservation of the herniated parenchyma and expansile cranioplasty.