Postoperative Central Nervous System Complications Research Articles

Autophagy impairment is involved in midazolam-induced lipid droplet accumulation and consequent phagocytosis decrease in BV2 cells

An increasing number of experimental and clinical observation suggest that the use of anaesthetics is closely associated with postoperative central nervous system (CNS) complications, such as delirium and cognitive dysfunction. Brain energy rescue is an emerging therapeutic strategy for central nervous system disease (CNSDs). However, the effect of anaesthetics on nerve cell energy utilisation, especially microglia, and its potential effects on cell function still unclear. Elucidating the effects of anaesthetics on lipid droplets, which are specific lipid storage organs, and phagocytosis of microglia is crucial to discover a new therapeutic concept for postoperative CNS complications. Here, we studied the effects of the commonly used anaesthetic midazolam on lipid droplets and phagocytosis in immortalised microglial BV2 cells. Lipid droplets were assessed by flow cytometry and triglyceride quantification. The phagocytosis of BV2 cells was evaluated by detecting their phagocytosis by latex beads. Additionally, the autophagy of BV2 cells was evaluated by western blot and observation under microscopy. Our results showed that midazolam caused lipid droplet accumulation and reduced phagocytosis in BV2 cells, and inhibition of lipid droplet accumulation partially restored phagocytosis. Furthermore, midazolam blocks autophagic degradation by increasing phosphorylated TFEB in BV2 cells, inhibition of midazolam-increased phosphorylated TFEB might contribute to the improvement of autophagic flux by rapamycin. Moreover, promoting autophagy reverse the lipid droplet accumulation and phagocytosis decrease. This study suggests autophagy is a target for attenuating lipid droplet accumulation, normal degradation of lipid droplets is important for maintaining microglia phagocytosis and attenuating the side effects of midazolam on the CNS.

Glycogen Synthase Kinase 3β Promotes Postoperative Cognitive Dysfunction by Inducing the M1 Polarization and Migration of Microglia.

Postoperative cognitive dysfunction (POCD) is a common postoperative central nervous system complication, especially in the elderly. It has been consistently reported that the pathological process of this clinical syndrome is related to neuroinflammation and microglial proliferation. Glycogen synthase kinase 3β (GSK-3β) is a widely expressed kinase with distinct functions in different types of cells. The role of GSK-3β in regulating innate immune activation has been well documented, but as far as we know, its role in POCD has not been fully elucidated. Lithium chloride (LiCl) is a widely used inhibitor of GSK-3β, and it is also the main drug for the treatment of bipolar disorder. Prophylactic administration of lithium chloride (2 mM/kg) can inhibit the expression of proinflammatory mediators in the hippocampus, reduce the hippocampal expression of NF-κB, and increase both the downregulation of M1 microglial-related genes (inducible nitric oxide synthase and CD86) and upregulation of M2 microglial-related genes (IL-10 and CD206), to alleviate the cognitive impairment caused by orthopedic surgery. In vitro, LiCl reversed LPS-induced production of proinflammatory mediators and M1 polarization of microglia. To sum up these results, GSK-3β is a key contributor to POCD and a potential target of neuroprotective strategies.

Skull Base Reconstruction with Multilayered Fascia Lata: A Single-Center 17 Years Experience.

Objective Reconstruction after open surgery of anterior skull base lesions is challenging. The fascia lata graft is our workhorse for achieving dural sealing and preventing cerebrospinal fluid leak and meningitis. This study seeks to analyze the donor and recipient site complication rates after fascia lata reconstruction. Methods This is a retrospective review of all open anterior skull base operations in which a double-layer fascia lata graft was used for the reconstruction of the defect from 2000 to 2016 at the Tel-Aviv Sourasky Medical Center, a tertiary referral center in Israel. Results Of the 369 patients operated for skull base lesions, 119 underwent open anterior skull base surgery and were reconstructed with a fascia lata graft. The patients' mean age was 47.1 years, and 68 (57.1%) were males. The overall postoperative early and late donor site complication rates were 6.7% ( n = 8) and 5.9% ( n = 7), respectively. Multivariate analysis found minor comorbidities and persistent/recurrent disease as being predictors for early-term complications. The overall postoperative early central nervous system (CNS) complication rate was 21.8% ( n = 26), while 12.6% ( n = 15) of the patients had late postoperative CNS complications. Conclusion Reconstruction of open anterior skull base lesions with fascia lata grafting is a safe procedure with acceptable complication and donor site morbidity rates.

Readmission Following Surgical Resection for Intractable Epilepsy: Nationwide Rates, Causes, Predictors, and Outcomes.

Hospital readmissions can be detrimental to patients and may interfere with the potential benefits of the therapeutic procedure. Government agencies have begun to focus on reducing readmissions; however, the etiology of readmissions is lacking. To report the national rates, risk factors, and outcomes associated with 30- and 90-d readmissions following surgery for intractable epilepsy. We queried the Nationwide Readmissions Database from January to September 2013 using International Classification of Diseases, Ninth Edition, Clinical Modification codes to identify all patients with intractable epilepsy, who underwent hemispherectomy (01.52), brain lobectomy (01.53), amydalohippocampectomy, or partial lobectomy (01.59). Predictor variables included epilepsy type, presurgical diagnostic testing, surgery type, medical complications, surgical complications, and discharge disposition. In 1587 patients, the 30- and 90-d readmission rates were 11.5% and 16.8%, respectively. The most common reasons for readmission were persistent epilepsy, video electroencephalography monitoring, postoperative infection, and postoperative central nervous system complication. In multivariable analysis, risk factors associated with both 30- and 90-d readmission were Medicare payer status, lowest quartile of median income, depression, hemispherectomy, and postoperative complications (P<.05). The only unique predictor of 30-d readmission was small bedsize hospital (P=.001). Readmissions within 30 d were associated with longer length of stay (6.8 vs 5.8 d), greater costs ($18 660 vs $15 515), and increased adverse discharges (26.4% vs 21.8%). Following epilepsy surgery, most readmissions that occurred within 30 d can be attributed to management of persistent epilepsy and predicted by Medicare payer status, depression, and complications. These data can assist the clinician in preventing readmissions and assist policy makers determine which admissions are potentially avoidable.

The Prevalence and Distribution of Occlusive Lesions of the Cerebral Arteries in Patients Undergoing Coronary Artery Bypass Graft Surgery

Intracranial cerebral atherosclerosis is a significant predictor of stroke after coronary artery bypass grafting (CABG). However, there is limited information on intracranial occlusive lesions in patients undergoing CABG. The purpose of the study was to elucidate the precise prevalence and distribution of occlusive lesions of the extracranial and intracranial arteries in patients undergoing CABG. Between 2009 and 2016, 205 patients underwent preoperative magnetic resonance angiography and elective CABG. The prevalence and the distribution of occlusive lesions were retrospectively examined by preoperative magnetic resonance angiography. Association between postoperative central nervous system (CNS) complications and the occlusive lesions was analyzed. Fifty-six patients (27.3%) and 60 patients (29.3%) had occlusive lesions of the extracranial and intracranial arteries, respectively. Twenty-eight patients (13.7%) had both extracranial and intracranial occlusive lesions. Thirty-one (15.1%) and 45 (22.0%) patients had severe stenosis or occlusion of the extracranial and intracranial arteries, respectively. The intracranial internal carotid artery was the most commonly affected intracranial artery (60 vessels; 62.5%), followed by the middle cerebral arteries (20 vessels; 20.8%). Sixteen patients (7.8%) suffered from postoperative CNS complications, including 2 permanent strokes. The etiology of the stroke was attributable to a predefined intracranial lesion in 1 patient. In multivariate analysis, the presence of intracranial occlusive lesions was found to have an independent association with the development of CNS complications (odds ratio 4.05; 95% confidence interval 1.13-14.6). The prevalence of intracranial occlusive lesions was higher than that of extracranial lesions in patients undergoing CABG. There was a solid trend toward the anterior distribution of the intracranial occlusive lesions.

Clinical implications of rhinosinusitis detected by preoperative computed tomography for endoscopic endonasal transsphenoidal pituitary surgery

Conclusions: Rhinosinusitis detected by preoperative osteomeatal unit computed tomography (OMU CT) may not increase the incidence of postoperative central nervous system (CNS) infections. Objectives: To evaluate the safety of endoscopic endonasal transsphenoidal pituitary surgery in patients who had rhinosinusitis detected by preoperative OMU CT. Methods: A total of 107 patients who underwent endoscopic endonasal transsphenoidal pituitary surgery were enrolled. The presence of rhinosinusitis and the location of involved sinuses were assessed by preoperative OMU CT. The extent of pituitary tumors was assessed by preoperative sellar MRI. The occurrence of intraoperative cerebrospinal fluid (CSF) leakage and postoperative central nervous system (CNS) complications were analyzed using the medical records. The correlations between these variables and postoperative CNS complications were examined. Results: After pituitary surgery, postoperative CNS complications occurred in four patients (3.7%). Twenty-eight patients (26.2%) had findings of rhinosinusitis on preoperative OMU CT. Of the 28 patients, 8 had rhinosinusitis in the anterior sinuses and 20 in the posterior sinuses. Intraoperative CSF leakage occurred in eight patients (7.5%). The occurrence of intraoperative CSF leakage showed a significant correlation with the incidence of postoperative CNS complications (p = 0.003) but not with the presence of rhinosinusitis (p = 0.134). Although not statistically significant, patients with rhinosinusitis in the posterior ethmoidal and/or sphenoidal sinuses tended to have higher incidences of postoperative CNS complications (p = 0.057).

Incidence of perioperative stroke after neck dissection for head and neck cancer: a regional outcome analysis.

To determine the incidence of perioperative stroke in patients undergoing a neck dissection. The incidence of perioperative stroke in non-head and neck surgery is between 0.08 and 0.2%. In contrast, a critical review of the literature identified 2 studies stating the incidence of perioperative stroke in head and neck surgery to be 3.2% and 4.8%. The implications of these results are significant because they suggest a potential need for preoperative screening and/or intervention for carotid artery pathology. This historical cohort study was conducted using discharge data for all neck dissections performed in a geographically-defined health region in Alberta, Canada, from 1994 to 2002. Subjects were selected for study if they had an assigned ICD-9CM procedure code for a neck dissection at one of the region's 3 adult-care hospitals. Our main outcome measure was perioperative stroke. Patients (n = 499) were identified as having had a neck dissection (mean age 56.5 +/- 15.3 SD, 65.3% male). Seven patients had ICD-9CM codes for postoperative central nervous system complications (incidence of 1.4%). However, on chart review, only one had had a true perioperative stroke corresponding to an incidence of 0.2% (95% confidence interval 0.01, 1.12). No missed strokes were found in a confirmatory random review of 10% of charts. The incidence of perioperative stroke in this study is significantly lower than that previously stated in the literature. This suggests that preoperative screening and/or intervention for carotid artery disease may not be necessary in this patient population.

Increased S100B in blood after cardiac surgery is a powerful predictor of late mortality

BackgroundLong-term outcome in patients who suffered stroke after undergoing a cardiac operation has been investigated sparingly, but increased long-term mortality has been reported. S100B is a biochemical marker of brain cell ischemia and blood–brain barrier dysfunction. The aim of this investigation was to record the long-term mortality in consecutive patients undergoing cardiac operations and to explore whether increased concentrations of S100B in blood had a predictive value for mortality. MethodsProspectively collected clinical variables, including S100B, in 767 patients who survived more than 30 days after a cardiac operation, were analyzed with actuarial survival analysis and 678 patients were analyzed with Cox multiple regression analysis. ResultsForty-nine patients (6.4%) were dead at follow-up (range, 18 to 42 months); 11.5% (88 of 767 patients) had elevated S100B 2 days after operation (range, 38 to 42 hours). The probability for death at follow-up was 0.239 if the S100B level was more than 0.3 μg/L, and 0.041 if it was less than 0.3 μg/L. The clinical variables independently associated with mortality were preoperative renal failure, preoperative low left ventricular ejection fraction, emergency operation, severe postoperative central nervous system complication, and elevated S100B values, which turned out to be the most powerful predictor. ConclusionsEven slightly elevated S100B values in blood 2 days after cardiac operation imply a bad prognosis for outcome, and especially so in combination with any central nervous system complication.

Carotid Surgery in Octogenarians in Veterans Affairs Medical Centers

The purpose of this study was to define outcomes after carotid surgery in octogenarians in the Veterans Affairs health care system. During fiscal years 1991–1994, 9152 patients in DRG 5 underwent extracranial vascular surgery procedures in Veterans Affairs medical centers. Those ≥80 years of age constituted 2.1% (n= 195) of such patients. In-hospital mortality rates were 1.03% (92/8957) in those <80 versus 3.08% (6/195) in those ≥80 years old (P= 0.018). Of those ≥80, 11.8% (23/195) had an ICD-9-CM-coded complication during hospitalization versus 11.2% of those <80 (1004/8957, NS). Surgical complications of the central nervous system (CNS) were present in 0.51% of octogenarians (1/195) and in 0.93% of those younger (83/8957, NS). Myocardial infarction (MI) occurred in 1.0% (2/195) of octogenarians and 0.74% (66/8967) of younger patients (NS). Patient Management Category software was used to define illness severity and resource intensity scale (RIS, a measure of resource utilization). Logistic regression analysis showed that age, illness severity, MI, and surgical complications of the CNS were associated with greater likelihood of mortality after extracranial vascular surgery. When the dichotomous variable “octogenarian status” was substituted for the continuous variable “age,” in this model, there was no significant association of octogenarian status per se with mortality, though the association of illness severity, MI, and CNS complications with mortality persisted. Illness severity was greater for octogenarians (2.03 ± 1.36) versus those younger (1.84 ± 1.13,P< 0.05). RIS was 2.57 ± 0.57 in octogenarians versus 2.47 ± 0.48 for younger patients (P< 0.015). Length of stay (LOS) was a mean of 3.2 days longer for octogenarians (P< 0.001). The risk of postoperative CNS complications was not higher in octogenarians. Mortality, resource utilization, and length of stay were, however, greater for octogenarians, but so was illness severity. Though mortality rates were greater for octogenarians in DRG 5, illness severity, MI, and postoperative CNS complications had greater impact on mortality after extracranial vascular surgery than octogenarian status per se.

Post-operative central nervous system complications

In the early post-operative period, unconsciousness may be related to anaesthetic events, hypoxic episodes, stroke, or embolic phenomena. Once anaesthetic effects have been eliminated from the differential diagnosis, investigations such as clinical neurological examination and computerised axial tomography may shed some light on the diagnosis. Electrophysiological monitoring may be useful in determining possible outcome. Before carrying out assessment of the unconscious patient, it is important to be certain that neuromuscular blockade has been adequately reversed. In the presence of a full train of four and sustained contraction to 50Hz supramaximal ulnar nerve stimulation, the effects of neuromuscular blocking agents can be assumed to be absent. Opioid analgesics are a common cause of failure to awaken after general anaesthesia. In the absence of other drugs affecting pupil size, pupillary constriction is a general effect of opioids and suggests that naloxone is indicated. Naloxone in 401xg increments to a total of 0.4mg

Carotid Duplex Sonography in Patients Undergoing Abdominal or Peripheral Vascular Surgery

Duplex carotid sonography was performed on 80 patients undergoing abdominal or peripheral vascular surgery for atherosclerotic disease. High-grade stenosis (over 50%) of one or both common or internal carotid arteries was present in 17 patients. In three of these patients ischemic cerebral infarcts developed in the territory of the most severely stenosed artery within 1 to 40 days after surgery. The other patients had no postoperative central nervous system complications. Duplex carotid sonography is indicated in patients prior to vascular surgery in order to identify the group at risk for the development of cerebrovascular accidents. Carotid endarterectomy prior to or at the time of surgery may prevent this complication.