Reza Gorji

Impact of anesthesia on mortality during endovascular clot removal for acute ischemic stroke.

Background: Endovascular clot retrieval is a technique available for removing intracranial arterial occlusions in acute ischemic stroke (AIS). This rescue therapy can be performed with moderate conscious sedation (CS) or general anesthesia (GA). The effect of GA on clinical outcome in AIS remains controversial. Therefore, we retrospectively investigated whether the use of CS or GA during endovascular intervention for AIS influenced outcomes. Methods: Patients who underwent emergent endovascular intervention for intracranial arterial occlusion during the years 2006 to 2012 were included in this study. Statistical analysis using the Spearman &rgr; was performed to examine demographic data and clinical outcomes between patients in the GA and CS groups. Binary logistic regression was used to determine the predictors of mortality. Results: A total of 109 patients fit the inclusion criteria. Among them, 35 patients had GA and 74 patients had CS. Patients needing intubation upon admission for airway protection were more likely to receive GA (P<0.001). The duration of the procedure and the time-to-revascularization from symptom onset were significantly longer in the GA group. Mortality was higher in the GA group compared with the CS group (40% vs. 22%, P=0.045). Multivariate analysis, controlled for confounding variables, identified GA and elevated postprocedure glucose level to be significant predictors of mortality. Conclusions: Larger prospectively randomized multicenter trials evaluating the effects of GA and CS on clinical and radiographic outcomes seems warranted.

The usefulness of intraoperative neurophysiological monitoring in cervical spine surgery: a retrospective analysis of 200 consecutive patients.

The usefulness of intraoperative neurophysiological monitoring (IONM), including somatosensory-evoked potential (SSEP) and transcranial electrical motor-evoked potentials (TcMEPs) in cervical spine surgery still needs to be evaluated. We retrospectively reviewed 200 cervical spine surgery patients from 2008 to 2009 to determine the role of IONM in cervical spine surgery. Total intravenous anesthesia was used for all patients. IONM alerts were defined as a 50% decrease in amplitude, a 10% increase in latency, or a unilateral change for SSEP and an increase in stimulation threshold of more than 100 V for TcMEP. Three patients had SSEP alerts that were related to arm malposition (2 patients) and hypotension (1 patient). Five patients had TcMEP alerts: 4 alerts were caused by hypotension and 1 by bone graft compression of the spinal cord. All alerts were resolved when causative reasons were corrected. There was no postoperative iatrogenic neurological injury. The sensitivities of SSEP and TcMEP alerts for detecting impending neurological injury were 37.5% and 62.5%, respectively. The sensitivity of both SSEP and TcMEP used in combination was 100%. No false-positive and false-negative alerts were identified in either SSEP or TcMEP (100% specificity). The total intravenous anesthesia technique optimizes the detection of SSEP and TcMEP and therefore improves the sensitivity and specificity of IONM. SSEP is sensitive in detecting alerts in possible malposition-induced ischemia or brachial plexus nerve injury. TcMEP specifically detects hypotension-induced spinal functional compromises. Combination use of TcMEP and SSEP enhances the early detection of impeding neurological damage during cervical spine surgery.

Brain Tissue Oxygen Monitoring to Assess Reperfusion after Intra-Arterial Treatment of Aneurysmal Subarachnoid Hemorrhage−Induced Cerebral Vasospasm: A Retrospective Study

BACKGROUND AND PURPOSE: Cerebral vasospasm resistant to medical management frequently requires intra-arterial spasmolysis. Angiographic resolution of vasospasm does not provide physiologic data on the adequacy of reperfusion. We recorded pre- and postspasmolysis PbO2 data in the endovascular suite to determine whether this physiologic parameter could be used to determine when successful reperfusion was established. MATERIALS AND METHODS: Eight patients with 10 Licox monitors and cerebral vasospasm underwent intra-arterial spasmolysis. Pre- and postspasmolytic PbO2 was recorded for comparison. Other physiologic parameters, such as CPP, ICP, SaO2, and Fio2, were also recorded. RESULTS: Mean prespasmolysis PbO2 recordings were 35.2 and 27.3 for the mild-to-moderate and moderate-to-severe vasospasm group, respectively. Mean postspasmolysis PbO2 increased to 40.3 and 38.4, respectively, which was statistically significant (P < .05) for both groups. In 100% of instances in the moderate-to-severe group and 83% of instances in mild-to-moderate group, the mean PbO2 increased after spasmolysis and correlated with improvement in angiographic vasospasm. Other physiologic parameters, such as CPP, ICP, SaO2, and Fio2, did not show any statistically significant difference before and after spasmolysis. CONCLUSIONS: PbO2 monitoring provides the interventionalist with an objective physiologic parameter to determine adequate spasmolysis. Further investigation is needed to establish target PbO2 rates indicative of adequate reperfusion, which can be used in the endovascular suite.

Fibrodysplasia ossificans progressiva: anesthetic management in complex orthopedic spine procedures

Fibrodysplasia ossificans progressiva (FOP) is a rare disorder of the connective tissue leading to progressive tissue ossification and immobilization. Soft-tissue trauma may exacerbate this condition, causing further ossification. Multisystem involvement includes restrictive lung disease, cervical ankylosis with limited mouth opening, and cardiac dysfunction. A 39-year-old woman with FOP presented with multiple orthopedic spine and femur fractures sustained from a fall. Anesthetic management was complicated by airway, pulmonary, and positioning challenges. Neuromonitoring allowed identification of spinal cord ischemia while avoiding a wake-up test.

Web-based educational activities developed by the Society for Neuroscience in Anesthesiology and Critical Care (SNACC): the experience of process, utilization, and expert evaluation.

Background: Web-based delivery of educational material by scientific societies appears to have increased recently. However, the utilization of such efforts by the members of professional societies is unknown. We report the experience with delivery of educational resources on the Web site of the Society for Neuroscience in Anesthesiology and Critical Care (SNACC), and utilization of those resources by members. Methods: Three web-based educational initiatives were developed over 1 year to be disseminated through the SNACC Web site (http://www.snacc.org) for society members: (1) The SNACC Bibliography; (2) “Chat with the Author”; and (3) Clinical Case Discussions. Content experts and authors of important new research publications were invited to contribute. Member utilization data were abstracted with the help of the webmaster. Results: For the bibliography, there were 1175 page requests during the 6-month period after its launch by 122/664 (19%) distinct SNACC members. The bibliography was utilized by 107/553 (19%) of the active members and 15/91 (16.5%) of the trainee members. The “Chats with the Authors” were viewed by 56 (9%) members and the Clinical Case Discussions by 51 (8%) members. Conclusions: Educational resources can be developed in a timely manner utilizing member contributions without additional financial implications. However, the member utilization of these resources was lower than expected. These are first estimates of utilization of web-based educational resources by members of a scientific society. Further evaluation of such utilization by members of other societies as well as measures of the effectiveness and impact of such activities is needed.

Spine Surgery and Intraoperative Monitoring

Major spine surgery involves multiple spine levels and may involve anterior/posterior procedures often with extensive instrumentation. This carries significant patient risk of higher morbidity and even mortality due to in part the reality that these patients may have multiple co-morbid conditions. Anesthesia management necessitates careful preoperative evaluation and intraoperative planning. Spine surgery poses potential risk to the spinal cord and nerves, consequently intraoperative neuromonitoring (IONM), somatosensory-evoked potentials (SSEPs), motor evoked potentials (MEPs), and electromyography (EMG), are used to test neurological function and hopefully avoid injury. Prone positioning is commonly used for posterior spinal decompression and fusion surgery. Pathophysiologic challenges of the prone position complicate the intraoperative anesthesia care of patients. Reduction in blood loss and goal directed fluid therapy during surgery improves patient outcome. Postoperatively, good pain control is very important to ensure a quick patient recovery. Both anesthesiologist and surgeon should be aware of postoperative vision loss (POVL), a rare but devastating complication commonly associated with extensive prone spine surgery. This chapter details the anesthetic management of severe cervical spinal stenosis. The questions in the chapter discuss preoperative evaluation, intraoperative management, IOM, and postoperative pain management. Controversial issues such as airway management with cervical pathology, IONM, intraoperative fluid and blood management, and prevention of POVL are emphasized.

Postoperative conversion disorder.

Conversion disorder is a psychiatric disorder in which psychological stress causes neurologic deficits. A 28-year-old female surgical patient had uneventful general anesthesia and emergence but developed conversion disorder 1 hour postoperatively. She reported difficulty speaking, right-hand numbness and weakness, and right-leg paralysis. Neurologic examination and imaging revealed no neuronal damage, herniation, hemorrhage, or stroke. The patient mentioned failing examinations the day before surgery and discontinuing her prescribed antidepressant medication, leading us to diagnose conversion disorder, with eventual confirmation by neuroimaging and follow-up examinations.

Multimodality Intraoperative Neurophysiological Monitoring during Onyx Embolization of Cerebrovascular Malformations

ABSTRACT General anesthesia prohibits neurological examination during embolization of cerebrovascular malformations when provocative testing prior to pedicle occlusion is needed. Intraoperative neurophysiological monitoring (IONM) has the potential to fill this gap but remains relatively unexplored. We conduct a retrospective review of consecutive patients with cerebrovascular malformations treated with Onyx® (ethylene vinyl alcohol copolymer, dissolved in dimethyl sulfoxide) embolization under general anesthesia with IONM from 2009 to 2012. Somatosensory evoked potentials (SSEPs), transcranial motor evoked potentials (TcMEPs), visual evoked potential (VEPs), auditory brainstem response (ABR), and electroencephalography (EEG) were used selectively in all patients depending on the location of the malformation. Provocative testing combined with IONM was performed in 28 patients over 75 sessions. Three patients demonstrated changes in TcMEPs or ABR during provocative testing, which halted the planned embolization. Two patients demonstrated changes in baseline SSEPs after embolization, despite normal IONM during provocative testing, correlating with postprocedural contralateral weakness. Six patients developed visual deficits after arterial occlusion despite unchanged VEPs and occipital EEG during provocative testing and embolization. We therefore conclude that the sensitivity of TcMEPs and SSEPs is preferable to EEG, and we strongly caution against relying on occipital recorded VEPs to predict visual deficits.

Development of Abdominal Compartment Syndrome in an 82-Year-Old Female Patient Immediately Following a Right Hip Arthroplasty

An 82-year-old female with past medical history significant for hypertrophic obstructive cardiomyopathy, atrial fibrillation and lymphoma underwent right hip arthroplasty. Aggressive fluid resuscitation prior to and during surgery was administered. At the completion of surgery, patient developed hypotension despite continuous fluid resuscitation and vasopressors infusion. The patient was found to have distended abdomen and emergent exploratory laparotomy was performed. Significantly elevated abdominal pressure (50 mmHg) and large amount ascites (1000 ml) were revealed. Patients hemodynamics was immediately improved after the abdomen was opened. A diagnosis of acute abdomen compartment syndrome was made. Possible contributory factors in this patient were discussed.

Deep hypothermic circulatory arrest for treatment of renal carcinoma

The case of a 67-year-old woman with multiple medical problems who presented for resection of a metastatic renal cell carcinoma involving the posterior fossa, is presented. Anesthetic management of the patient, who suffered metastasis to the brain, and who required deep hypothermic circulatory arrest, is discussed.