Mechanisms of perioperative cerebral infarction

Intraoperative Blood Pressure Variability and Early Postoperative Stroke: A Case-Control Study

BACKGROUND

This study aims to assess the association of postoperative stroke with intraoperative hemodynamic variability and transfusion management.

METHODS

In this case-control study, adult patients (≥ 18 years) who had a stroke within 72 hours of a surgical procedure were matched to 2 control patients according to age, sex, and procedure type. Primary risk factors assessed were intraoperative fluid administration, blood product transfusion, vasopressor use, and measures of variability in systolic and diastolic blood pressure and heart rate: maximum, minimum, range, SD, and average real variability. The variables were analyzed with conditional logistic regression, which accounted for the 1:2 matched case-control study design.

RESULTS

Among 687 581 procedures, we identified 64 postoperative strokes (incidence, 9.3 [95% CI, 7.2-11.9] strokes per 100 000 procedures). These cases were matched with 128 controls. Stroke cases had higher Charlson cmorbidity index scores than did controls (P = .046). Blood pressure and heart rate variability measures were not associated with stroke. The risk of stroke was increased with red blood cell (RBC) transfusion (odds ratio [OR], 14.82; 95% CI, 3.40-64.66; P < .001), vasopressor use (OR, 3.91; 95% CI, 1.59-9.60; P = .003), and longer procedure duration (OR, 1.23/h; 95% CI, 1.01-1.51; P = .04). Multivariable analysis of procedure duration, RBC transfusion, and vasopressor use showed that only RBC transfusion was independently associated with an increased risk of stroke (OR, 10.10; 95% CI, 2.14-47.72; P = .004).

CONCLUSIONS

Blood pressure variability was not associated with an increased risk of postoperative stroke; however, RBC transfusion was an independent risk factor.

A Single Center Study on the Risks of Peri-Intervention Stroke in Thoracic Endovascular Aortic Repair (TEVAR) and Endovascular Abdominal Aortic Repair (EVAR)

(1) Background: The risk factors of peri-intervention stroke (PIS) in thoracic endovascular aortic repair (TEVAR) and endovascular abdominal aortic repair (EVAR) are different. This study aimed to compare the risks of PIS in both interventions. (2) Methods: Patients who had suffered a PIS related to TEVAR or EVAR from January 2008 to June 2015 in Songklanagarind Hospital were selected as the cases, while patients who had not suffered PIS were randomly selected to create a 1:4 case: control ratio for analysis. The associations between the factors from pre- to post-intervention and PISs in TEVAR or EVAR cases were analyzed by univariable analysis (p < 0.1). The independent risks of PIS were identified by multivariable analysis and presented in odds ratios (p < 0.05). (3) Results: A total of 17 (2.2%) out of 777 patients who had undergone TEVAR or EVAR experienced PIS, of which 9/518 (1.7%) and 8/259 (3.1%) cases were in TEVAR and EVAR groups, respectively. PIS developed within the first 24 h in nine (52.9%) cases. Large vessel ischemic stroke or watershed infarctions were the most common etiologies of PIS. The independent risks of PIS were the volume of intra-intervention blood loss (1.99 (1.88–21.12), p < 0.001) in the TEVAR-related PIS, and intervention time (2.16 (1.95–2.37), p = 0.010) and post-intervention hyperglycemia (18.60 (1.60–216.06), p = 0.001) in the EVAR-related PIS. There were no differences in the rate of PIS among the operators, intervention techniques, and status of the interventions performed. (4) Conclusion: The risks of PIS in TEVAR or EVAR in our center were different and possibly independent of the operator expertise and intervention techniques.

Perioperative Stroke and Thirty-Day Hospital Readmission After Cardiac Surgeries: State Inpatient Database Study

BACKGROUND

Readmission rates are an important metric for evaluating healthcare quality. Stroke is a major complication following cardiac surgery. Our study aimed to evaluate the frequency and predictors of 30-day unplanned hospital readmission after cardiac surgeries and to evaluate the impact of perioperative stroke on readmission.

METHODS

Surgical discharge records spanning the years of 2008 through 2011 were analyzed utilizing California State Inpatient Database. International Classification of Diseases, ninth revision-Clinical Modification (ICD-9-CM) codes and Clinical Classification Software (CCS) codes were used to identify surgeries and variables of interest. Surgical records were then followed up for 30 days through linking admission records. Perioperative stroke was defined as brain infarction of ischemic or hemorrhagic etiology that occurred during or within 30 days after surgery.

RESULTS

Baseline characteristics associated with increased readmission rates were female gender, age above 65, non-white race, lower income, and increased number of comorbidities. Among 199,617 hospitalizations for cardiac surgeries, 1,817 (0.91%) patients developed perioperative stroke. The rate of readmission in perioperative stroke patients was 21.89%. They had a longer length of hospital stay and their discharge was vastly non-routine (84%). Our univariate analysis yielded significant association between stroke and readmission rates (odds ratio: 1.82, 95% confidence interval: 1.63 - 2.04). This association failed to remain significant upon controlling for other variables in our multivariate analysis.

CONCLUSION

Baseline patient characteristics and perioperative complications are significant predictors of readmission. More than one in five patients who develop a stroke after cardiac surgery are readmitted to the hospital within 30 days of discharge.

Effect of Intraoperative Arterial Hypotension on the Risk of Perioperative Stroke After Noncardiac Surgery: A Retrospective Multicenter Cohort Study

BACKGROUND

Intraoperative cerebral blood flow is mainly determined by cerebral perfusion pressure and cerebral autoregulation of vasomotor tone. About 1% of patients undergoing noncardiac surgery develop ischemic stroke. We hypothesized that intraoperative hypotension within a range frequently observed in clinical practice is associated with an increased risk of perioperative ischemic stroke within 7 days after surgery.

METHODS

Adult noncardiac surgical patients undergoing general anesthesia at Beth Israel Deaconess Medical Center and Massachusetts General Hospital between 2005 and 2017 were included in this retrospective cohort study. The primary exposure was intraoperative hypotension, defined as a decrease in mean arterial pressure (MAP) below 55 mm Hg, categorized into no intraoperative hypotension, short (<15 minutes, median [interquartile range {IQR}], 2 minutes [1-5 minutes]) and prolonged (≥15 minutes, median [IQR], 21 minutes [17-31 minutes]) durations. The primary outcome was a new diagnosis of early perioperative ischemic stroke within 7 days after surgery. In secondary analyses, we assessed the effect of a MAP decrease by >30% from baseline on perioperative stroke. Analyses were adjusted for the preoperative STRoke After Surgery (STRAS) prediction score, work relative value units, and duration of surgery.

RESULTS

Among 358,391 included patients, a total of 1553 (0.4%) experienced an early perioperative ischemic stroke. About 42% and 3% of patients had a MAP of below 55 mm Hg for a short and a prolonged duration, and 49% and 29% had a MAP decrease by >30% from baseline for a short and a prolonged duration, respectively. In an adjusted analysis, neither a MAP <55 mm Hg (short duration: adjusted odds ratio [ORadj], 0.95; 95% confidence interval [CI], 0.85-1.07; P = .417 and prolonged duration: ORadj, 1.18; 95% CI, 0.91-1.55; P = .220) nor a MAP decrease >30% (short duration: ORadj, 0.97; 95% CI, 0.67-1.42; P = .883 and prolonged duration: ORadj, 1.30; 95% CI, 0.89-1.90; P = .176) was associated with early perioperative stroke. A high a priori stroke risk quantified based on preoperatively available risk factors (STRAS prediction score) was associated with longer intraoperative hypotension (adjusted incidence rate ratio, 1.04; 95% CI, 1.04-1.05; P < .001 per 5 points of the STRAS prediction score).

CONCLUSIONS

This study found no evidence to conclude that intraoperative hypotension within the range studied was associated with early perioperative stroke within 7 days after surgery. These findings emphasize the importance of perioperative cerebral blood flow autoregulation to prevent ischemic stroke.

Relationship between bone disorders and stroke

Bone disorders are among the most uncommon causes of stroke, but they should be considered as stroke cause in particular clinical scenarios. On the other hand, osteoporosis/osteopenia and increased fracture risk are well documented post stroke complications. The relationship between stroke and bone health is complex. The current facts suggest that these two conditions share same risk factors, but also are risk factors for each other. However, the evidence shows more clear effect of stroke on the bone health, than in the opposite direction. This extensive review is aiming to fill the huge gap of evidence about this topic, and since bone pathology is extremely rare cause of cerebrovascular accident, although a complex connection between these two conditions definitely exists.

Perioperative Stroke in a Patient Undergoing Noncardiac, Non-Neurosurgical Procedure: A Case Report

Perioperative stroke is a focal or global neurological deficit lasting more than 24 hours, which occurs during the surgery or within 30 days following surgery. Medications administered during anesthesia mask the symptoms of stroke in the perioperative period and make the early diagnosis of stroke difficult. Postoperative endothelial dysfunction and surgery-induced hypercoagulable state are some of the factors contributing to perioperative stroke. This report describes a case of perioperative stroke in a patient with an unremarkable intraoperative course following otolaryngology surgery. Vigilance, early diagnosis, and prompt treatment with the help of the acute stroke team are pivotal in improving patient outcomes.

Increased Risk of Perioperative Ischemic Stroke in Patients Who Undergo Noncardiac Surgery with Preexisting Atrial Septal Defect or Patent Foramen Ovale

OBJECTIVES

To evaluate whether a preoperative diagnosis of atrial septal defect (ASD) or patent foramen ovale (PFO) is associated with perioperative stroke in noncardiac surgery and their outcomes.

DESIGN

Retrospective cohort analysis.

SETTING

United States hospitals.

PARTICIPANTS

Adults patients (≥18 years old) who underwent major noncardiac surgery from 2010 to 2015 were identified using the Healthcare Cost and Utilization Project's National Readmission Database.

INTERVENTIONS

Preoperative diagnosis of ASD or patent foramen ovale.

MEASUREMENTS AND MAIN RESULTS

Among the 19,659,161 hospitalizations for major noncardiac surgery analyzed, 12,248 (0.06%) had a preoperative diagnosis of ASD/PFO. Perioperative ischemic stroke occurred in 723 (5.9%) of patients with ASD/PFO and 373,291 (0.02%) of those without ASD/PFO (adjusted odds ratio [aOR], 16.7; 95% confidence interval [CI]: 13.9-20.0). Amongst the different types of noncardiac surgeries, obstetric, endocrine, and skin and burn surgery were associated with higher risk of stroke in patients with pre-existing ASD/PFO. Moreover, patients with ASD/PFO also had an increased in-hospital mortality (aOR, 4.6, 95% CI: 3.6-6.0), 30-day readmission (aOR, 1.2, 95% CI: 1.04-1.38), and 30-day stroke (aOR, 7.2, 95% CI: 3.1-16.6). After adjusting for atrial fibrillation, ischemic stroke remained significantly high in the ASD/PFO group (aOR: 23.7, 95%CI 19.4-28.9), as well as in-hospital mortality (aOR: 5.6, 95% CI 4.1-7.7), 30-day readmission (aOR: 1.19, 95%CI 1.0-1.4), and 30-day stroke (aOR: 9.3, 95% CI 3.7-23.6).

CONCLUSIONS

Among adult patients undergoing major noncardiac surgery, pre-existing ASD/PFO is associated with increased risk of perioperative ischemic stroke, in-hospital mortality, 30-day stroke, and 30-day readmission after surgery.

Intraoperative Ischemic Stroke in Elective Spine Surgery: A Retrospective Study of Incidence and Risk

STUDY DESIGN

. Retrospective study.

OBJECTIVE

. To determine incidence, risk factors, complications, and early postoperative outcome in patients with intraoperative ischemic stroke during elective spine surgery.

SUMMARY OF BACKGROUND DATA

. Overall, stroke is the fifth leading cause of death in the United States and the second leading cause of death worldwide. It can be a catastrophic event and the main cause of neurological disability in adults.

METHODS

. A retrospective review of the electronic medical records of patients who underwent elective spine surgery between January 2016 and November 2018 at a larger tertiary referral center was conducted. Patients with infection and neoplastic disease were excluded. Patient demographics, pre- and postoperative neurological status, surgical treatment, surgical time, blood loss, intraoperative abnormalities, risk factors, history of stroke, medical treatment, diagnostics, hospital stay, complications, and mortality were collected.

RESULTS

. Out of 5029 surgically treated patients receiving elective spine surgery, a total of seven patients (0.15%) were identified who developed an ischemic stroke during the surgical procedure. Patients were predominantly females (n = 6). Ischemic pontine stroke occurred in two patients. Further distributions of ischemic stroke were: left caudate nucleus, left posterior inferior cerebellar artery, left external capsule, left middle cerebral artery, and acute ischemic supratentorial spots. The main risk factors identified for intraoperative ischemic stroke include hypertension, diabetes, smoking, dyslipidemia, and possibly major intraoperative CSF leak. Three patients (43%) had neurological deficits which did not improve during hospital stay. Two patients recovered fully and two patients died. Therefore, in-hospital mortality rate of this subset of patients was 29%.

CONCLUSION

. With the increase of spinal procedures, it is important to identify patients at risk for having an ischemic stroke and to optimize their comorbidities preoperatively. Patients with intraoperative ischemic stroke carry a higher risk for morbidity and mortality during the index hospitalization.

LEVEL OF EVIDENCE

4.

The Association Between Mild Intraoperative Hypotension and Stroke in General Surgery Patients

BACKGROUND

Intraoperative hypotension may contribute to perioperative strokes. We therefore tested the hypothesis that intraoperative hypotension is associated with perioperative stroke.

METHODS

After institutional review board approval for this case-control study, we identified patients who had nonneurological, noncardiac, and noncarotid surgery under general anesthesia at the Cleveland Clinic between 2005 and 2011 and experienced a postoperative stroke. Control patients not experiencing postoperative stroke were matched in a 4-to-1 ratio using propensity scores and restriction to the same procedure type as stroke patients. The association between intraoperative hypotension, measured as time-integrated area under a mean arterial pressure (MAP) of 70 mm Hg, and postoperative stroke was assessed using zero-inflated negative binomial regression.

RESULTS

Among 106 337 patients meeting inclusion criteria, we identified 120 who had confirmed postoperative stroke events based on manual chart review. Four-to-one propensity matching yielded a final matched sample of 104 stroke cases and 398 controls. There was no association between stroke and intraoperative hypotension. Stroke patients were not more likely than controls to have been hypotensive (odds ratio, 0.49 [0.18-1.38]), and among patients with intraoperative hypotension, stroke patients did not experience a greater degree of hypotension than controls (ratio of geometric means, 1.07 [0.76-1.53]).

CONCLUSIONS

In our propensity score-matched case-control study, we did not find an association between intraoperative hypotension, defined as MAP < 70 mm Hg, and postoperative stroke.

Perioperative strokes after coronary artery bypass grafting with staged carotid endarterectomy: A nationwide perspective

STUDY OBJECTIVE

To examine the risk of perioperative stroke on in-hospital morbidity and mortality in staged coronary artery bypass grafting (CABG) and carotid endarterectomy (CEA) procedures.

DESIGN

The National Inpatient Sample (NIS) database was used to extract data on all patients who underwent staged CABG CEA procedures. They were identified using the ICD-9 (International Classification of Diseases, Ninth Revision-Clinical Modification) diagnosis and procedure codes.

SETTING

Multi-institutional.

PATIENTS

Patients who underwent staged CABG and CEA from 1999 to 2011.

INTERVENTIONS

Staged CABG and CEA procedures.

MEASUREMENTS

Various pre-operative, and perioperative risk factors and their association with in-hospital mortality and morbidity were studied.

MAIN RESULTS

The study cohort was grouped into 2761 patients who underwent staged CEA and CABG. The average age of the patient population was 69years. An in-hospital mortality of 4.96% (137) was observed. Staged procedures showed a morbidity rate of 69.21%. Patients with perioperative strokes had a mortality rate of 16.73% following staged procedures. Other notable risk factors for mortality and morbidity were post-operative myocardial infarction (MI) and congestive heart failure (CHF).

CONCLUSION

Analysis of 2761 patients over a period of 12years (1999-2011) indicate perioperative stroke to be a strong post-operative predicator of in-hospital mortality and morbidity for staged procedures. Other significant factors such as advancing age, female gender and comorbidities like CHF, left ventricular dysfunction (LVD) and post-operative MI should also be considered when determining patient risk. Further investigative studies on staged CABG and CEA procedures are needed for better patient selection and for implementing preventative strategies such as neuroprotective medication and neuromonitoring to minimize the risk of ischemic strokes.

[Epidemiology of cerebral perioperative vascular accidents]

OBJECTIVES

Stroke is a well-described postoperative complication, after carotid and cardiac surgery. On the contrary, few studies are available concerning postoperative stroke in general non-cardiac non-carotid surgery. The high morbid-mortality of stroke justifies an extended analysis of recent literature.

ARTICLE TYPE

Systematic review.

DATA SOURCES

Firstly, Medline and Ovid databases using combination of stroke, cardiac surgery, carotid surgery, general non-cardiac non-carotid surgery as keywords; secondly, national and European epidemiologic databases; thirdly, expert and French health agency recommendations; lastly, reference book chapters.

RESULTS

In cardiac surgery, with an incidence varying from 1.2 to 10% according to procedure complexity, stroke occurs peroperatively in 50% of cases and during the first 48 postoperative hours for the others. The incidence of stroke after carotid surgery is 1 to 20% according to the technique used as well as operator skills. Postoperative stroke is a rare (0.15% as mean, extremes around 0.02 to 1%) complication in general surgery, it occurs generally after the 24-48th postoperative hours, exceptional peroperatively, and 40% of them occurring in the first postoperative week. It concerned mainly aged patient in high-risk surgeries (hip fracture, vascular surgery). Postoperative stroke was associated to an increase in perioperative mortality in comparison to non-postoperative stroke operated patients.

CONCLUSION

Postoperative stroke is a quality marker of the surgical teams' skill and has specific onset time and induces an increase of postoperative mortality.

Impact of perioperative acute ischemic stroke on the outcomes of noncardiac and nonvascular surgery: a single centre prospective study

BACKGROUND

Although ischemic stroke is a well-known complication of cardiovascular surgery it has not been extensively studied in patients undergoing noncardiac surgery. The aim of this study was to assess the predictors and outcomes of perioperative acute ischemic stroke (PAIS) in patients undergoing noncardiothoracic, nonvascular surgery (NCS).

METHODS

We prospectively evaluated patients undergoing NCS and enrolled patients older than 18 years who underwent an elective, non-daytime, open surgical procedure. Electrocardiography and cardiac biomarkers were obtained 1 day before surgery, and on postoperative days 1, 3 and 7.

RESULTS

Of the 1340 patients undergoing NCS, 31 (2.3%) experienced PAIS. Only age (odds ratio [OR] 2.5, 95% confidence interval [CI] 1.01-3.2, p < 0.001) and preoperative history of stroke (OR 3.6, 95% CI 1.2-4.8, p < 0.001) were independent predictors of PAIS according to multivariate analysis. Patients with PAIS had more cardiovascular (51.6% v. 10.6%, p < 0.001) and noncardiovascular complications (67.7% v. 28.3%, p < 0.001). In-hospital mortality was 19.3% for the PAIS group and 1% for those without PAIS (p < 0.001).

CONCLUSION

Age and preoperative history of stroke were strong risk factors for PAIS in patients undergoing NCS. Patients with PAIS carry an elevated risk of perioperative morbidity and mortality.

Suspected intraoperative formation of left atrial thrombus in a patient with atrial fibrillation receiving bridging anticoagulation therapy

We present a patient with atrial fibrillation (AF) in whom a left atrial (LA) thrombus might have formed during laparotomy despite bridging anticoagulation therapy. No evidence of thrombus was detected by transesophageal echocardiography (TEE) at the start of surgery; however, a thrombus measuring 13 × 10 mm was found in the LA appendage by the end of the procedure, suggesting that thrombus might develop intraoperatively in patients with AF even when bridging anticoagulation is properly established. Intraoperative TEE can assist in detecting intracardiac thrombus in patients with AF regardless of their anticoagulation status and provides a tool for intervention to prevent systemic embolization.

[Pituitary apoplexy: a rare complication in the postoperative period]

Postoperative pituitary apoplexy is an exceptional but life-threatening complication. We report the case of a 62-year-old man who underwent a cystoprostatectomy under general anaesthesia. The immediate postoperative course was complicated by asthenia and an altered state of consciousness. A few days later, a homonymous followed by bitemporal hemianopia developed. A CT-scan and magnetic resonance imaging made the diagnosis o pituitary apoplexy. The treatment was a medical one, with rapid improvement in the patient's condition.

Postoperative coma in a patient with complete basilar syndrome after anterior cervical discectomy

PURPOSE

Ischemic brainstem stroke resulting from occlusion of the basilar artery during cervical spine surgery in a previously asymptomatic patient is a rare event. We report the development of a large ischemic brainstem stroke, resulting from occlusion of the basilar artery during anterior cervical discectomy, in a patient without previous neurological deficit, or signs of vertebrobasilar insufficiency.

CLINICAL FEATURES

A 55-yr-old, diabetic and hypertensive male who developed a cervical spine infection, underwent surgery for anterior discectomy at C5-C6. During the 2.5-hr long procedure the patient was lying supine with his neck hyperextended. Except for a temporary reduction in systolic blood pressure, the intraoperative course was uneventful. At the end of surgery the patient remained unconscious with flaccid paralysis in all extremities, fixed pinpoint pupils, low respiratory rate, and no response to painful stimuli. Naloxone administration did not improve the clinical picture, while brain computed tomography showed a large brainstem and cerebellar stroke, implicating basilar artery occlusion. The patient died five days later from stroke complications. Intraoperative surgical manipulation with a severely inflamed vertebral system, as well as prolonged neck hyperextension occluding the blood flow of vertebrobasilar arteries might have contributed to fatal brainstem stroke in this patient.

CONCLUSION

Neck surgery carries a potential risk for posterior circulation stroke, and this report heightens awareness of this rare, but serious complication.

Cerebral ischemia during shoulder surgery in the upright position: a case series

We report 4 cases of ischemic brain and spinal cord injury after shoulder surgery in the beach chair position, using data from medical legal case reviews. We argue that the correlation between cardiovascular risk factors and cerebral ischemic complications for this type of surgery is poor in these middle-aged patients. Rather, our analysis suggests that the sitting position and the head position create specific physiological conditions that may be conducive to cerebral and spinal cord ischemia during this type of surgery. Thromboembolic events may be an additional cause of adverse neurologic outcomes.

Thromboelastography maximum amplitude predicts postoperative thrombotic complications including myocardial infarction

Postoperative thrombotic complications increase hospital length of stay and health care costs. Given the potential for thrombotic complications to result from hypercoagulable states, we sought to determine whether postoperative blood analysis using thromboelastography could predict the occurrence of thrombotic complications, including myocardial infarction (MI). We prospectively enrolled 240 patients undergoing a wide variety of surgical procedures. A cardiac risk score was assigned to each patient using the established revised Goldman risk index. Thromboelastography was performed immediately after surgery and maximum amplitude (MA), representing clot strength, was determined. Postoperative thrombotic complications requiring confirmation by a diagnostic test were assessed by a blinded observer. Ten patients (4.2%) suffered a total of 12 postoperative thrombotic complications. The incidence of thrombotic complications with increased MA (8 of 95 = 8.4%) was significantly (P = 0.0157) more frequent than that of patients with MA < or =68 (2 of 145 = 1.4%). Furthermore, the percentage suffering postoperative MI in the increased MA group (6 of 95 = 6.3%) was significantly larger than that in the MA < or =68 group (0 of 145 = 0%) (P = 0.0035). In a multivariate analysis, increased MA (P = 0.013; odds ratio, 1.16; 95% confidence interval, 1.03-1.20) and Goldman risk score (P = 0.046; odds ratio, 2.39; 95% confidence interval, 1.02-5.61) both independently predicted postoperative MI. A postoperative hypercoagulable state as determined by thromboelastography is associated with postoperative thrombotic complications, including MI, in a diverse group of surgical patients.

Ein zerebraler Grenzzoneninfarkt nach Allgemeinan�sthesie bei einem Patienten mit erh�hten Antikardiolipinantik�rpern

During the first generalised epileptic attack, a patient suffered a humerus fracture which necessitated an operation. This patient also had a history of spontaneous lung emboli and an elevated anti-cardiolipin plasma level for which coumarin was prescribed but was stopped preoperatively. After induction of general anaesthesia for a total shoulder arthroplasty, the patient became hypotensive and the bispectral index recorded perioperatively dropped to 0. Postoperatively, the patient developed signs of a unilateral borderzone cerebral infarct in the area of the medial cerebral artery. The possible pathomechanisms involved are discussed. In cases of known cerebral pathology intraoperative hypotension should be avoided by at all costs. Patients with increased anti-cardiolipin antibody levels and who suffer from epileptic attacks have an increased risk of thromboembolic events.

Perioperative stroke caused by arterial tumor embolism

Rarely, cancer invades a pulmonary vein and subsequently embolizes to the cerebral circulation, causing a stroke. Tumor embolism typically involves large, centrally located lung tumors. We report a case of immediate postoperative stroke caused by an arterial tumor embolism during pulmonary resection of metastatic sarcoma. This case is unique because the resected lesions were smaller than those previously associated with tumor embolism and unusual in that the tumors were peripherally located. Tumor embolization should be considered in the differential diagnosis of stroke after lung cancer surgery even with small, peripherally located pulmonary malignancies.

IMPLICATIONS

We present a case of stroke diagnosed in the recovery room after lung cancer resection. The cause of the stroke was tumor that embolized from the lung to the middle cerebral artery. Tumor embolism should be considered in the differential diagnosis of immediate postoperative stroke after lung cancer surgery.

In-hospital stroke

Between 6.5% and 15.0% of all strokes occur in patients already in hospital, many of whom are there for surgical procedures or cardiac disorders. This important group of patients could potentially be assessed more rapidly than others and could be candidates for interventional therapies. However, delays in recognition and assessment are common, possibly related to comorbidities and the complexities of hospital practice. Risk factors for in-hospital stroke include specific operations and procedures (eg, cardiac surgery), previous medical disorders (especially a history of stroke), and certain physiological characteristics (including fever and dehydration). The stroke subtype is embolic in a large proportion, and there are various possible precipitating mechanisms. Outcome can be poor, with high mortality. Interventional therapies, particularly thrombolysis, are possible options. In the postoperative setting, intra-arterial thrombolysis is feasible and reasonably safe in carefully selected patients. Experimental agents and the manipulation of physiological variables are other treatment possibilities that could be applied early in this group of patients. Increasing the awareness by hospital physicians of such interventions may be an important factor that reduces delays in assessment of patients who have stokes while in hospital.

Perioperative stroke: evaluation, management, and possible preventive measures

Mechanisms of perioperative ischemic stroke include: hypotension, hypercoagulability, arrhythmias with embolism, or direct vascular insult. Mechanisms of perioperative hemorrhagic stroke include: use of antithrombotics, hypertension, or direct vascular insult.

Stroke in the postoperative period

Stroke in the postoperative period requires a certain level of sophistication in dealing not only with the patient, but also with the family and significant others. The consultant who is called in to assess the patient must deal with the delicate matter of addressing a presumably unforeseen complication; this often requires political deftness when the surgeon is reluctant to acknowledge that anything possibly could go awry. It is the ultimate hope of all involved that the patient will have a speedy and full recovery. It is important for the patient to be evaluated properly and thoroughly in an effort to prevent a minor, reversible deficit from becoming a major, irreversible neurologic disability. Family members should have all findings and the implications of such findings thoroughly explained to them. Efforts to minimize the potential ramifications of a postoperative stroke generally are not well received and can lead to questions about the integrity of the surgical team as well as the quality of care.

The effect of perioperative aspirin therapy in peripheral vascular surgery: a decision analysis

Patients who undergo infrainguinal revascularization surgery are at increased risk for perioperative thrombotic complications. Aspirin decreases thrombotic events in the nonoperative setting; however, aspirin is often discontinued to avoid perioperative hemorrhagic complications. We used a decision analysis to determine whether aspirin should be discontinued before infrainguinal revascularization surgery. Two strategies were compared: aspirin cessation 2 wk before surgery and aspirin continuation throughout the perioperative period. Clinical events examined included myocardial infarction, thrombotic cerebrovascular accident, hemorrhagic cerebrovascular accident, gastrointestinal hemorrhage, and incisional hemorrhagic complications. Event rates and effect of aspirin were obtained by using MEDLINE. The outcomes were perioperative mortality, life expectancy, and quality-adjusted life expectancy. According to the model, continued aspirin use decreased perioperative mortality rates from 2.78% to 2.05%. Continued aspirin use increased life expectancy from 14.83 to 14.89 yr and increased quality-adjusted life expectancy from 14.72 to 14.79 yr. Aspirin increased the number of hemorrhagic complications by 2.46%, primarily because of an increased incidence of non-life-threatening complications.

A review of comorbidities and spinal surgery

As the population ages, greater numbers of elderly patients will be considered for spinal surgery for spinal stenosis and complex primary and revision reconstructions. The age-related medical comorbidities impact not only on the decision to undertake a procedure but also impact the magnitude of the procedure. The surgeon must understand aging and medical comorbidities to facilitate preoperative decision-making and postoperative care. A review of the more common age-related pathophysiologic changes to the cardiovascular, pulmonary, and central nervous systems is undertaken. General recommendations for perioperative treatment are made relative to published series regarding the impact of age and medical comorbidities on short- and long-term outcomes.

Perioperative stroke associated with postoperative epidural analgesia

A patient with an epidural catheter for postoperative analgesia developed a stroke in association with a hypotensive episode resulting from a bolus of local anesthetic. After undergoing resection for femoral chondrosarcoma under epidural anesthesia, the patient received a continuous infusion of epidural morphine for postoperative analgesia. Lidocaine 1% (10 mL in divided doses) was administered through the catheter for breakthrough pain. The patient experienced a hypotensive episode and was noted to have a motor and cortical sensory deficit of the left arm and leg 8 hours after the hypotensive episode. Clinical presentation and subsequent workup were consistent with a watershed infarction. The patient recovered full neurologic function before discharge. Postoperative hypotension from epidural analgesia may be associated with stroke; however, a cause-and-effect relationship usually cannot be established with certainty.

Bilateral cortical blindness after lumbar spine surgery. A case report

STUDY DESIGN

A report of the unusual perioperative complication of bilateral cortical blindness after lumbar spine surgery. The hypothetical causes that can lead to this syndrome in spine surgery and the precautions are discussed.

OBJECTIVES

The circumstances surrounding the occurrence of perioperative cortical blindness, the explanation of possible mechanisms, and the patients at risk are evaluated.

SUMMARY OF BACKGROUND DATA

There have been no similar reports.

METHODS

Case report with description of the syndrome of cortical blindness, the diagnostic tools, and the different pathophysiologic causes.

RESULTS

The severe impairment of visual capacities remained unchanged; some color discrimination and the differentiation between dark and daylight were possible.

CONCLUSIONS

In obese patients (body mass index > 30) puncture of the subclavian vein and rotating and positioning of the patient in one step should be performed carefully.

Cerebral infarct following central venous cannulation

Inadvertent carotid artery puncture is a well-known complication of internal jugular vein cannulation. A case of cerebral infarct subsequent to carotid artery puncture during internal jugular vein cannulation is reported.

Stroke is an emergency

Stroke is an emergency. Ischemic stroke is similar to myocardial infarction in that the pathogenesis is loss of blood supply to the tissue, which can result in irreversible damage if blood flow is not restored quickly. Public education is needed to emphasize the warning signs of stroke. Patients should seek medical help immediately, using emergency transport systems. Therapy geared toward minimizing the damage from an acute stroke should be started without delay in the emergency room. This includes measures to protect brain tissue, support perfusion pressure, and minimize cerebral edema. Strategies for improving recovery should also begin immediately. All major medical centers need stroke teams and stroke units. Stroke prevention should be given high priority as a public health strategy. Risk factor management should be part of general health care and should begin in childhood, with emphasis on nutrition, exercise, weight control, and avoidance of tobacco. Health screening and early treatment of hypertension and hypercholesterolemia has decreased the incidence of stroke and heart disease, but these efforts need to be expanded to reach all segments of the population. Basic research has opened the door to new therapies aimed at re-establishing blood flow and limiting tissue damage. Clinical trials have already led to changes in stroke prevention, including studies of carotid endarterectomy and ticlopidine and warfarin therapy (for patients with atrial fibrillation). Trials in progress are testing the usefulness of ancrod, neuroprotective agents, antioxidant agents, anti-inflammatory agents, low-molecular-weight heparin, thrombolytic drugs, and angioplasty. Any delay starting therapy after an acute stroke will result in progressive, irreversible loss of brain tissue. Clinicians should remember that for a stroke patient, time is brain tissue.

Perioperative stroke in patients undergoing head and neck surgery

The risk of perioperative strokes has been demonstrated to be very low in general surgical procedures, and somewhat higher in cardiac and carotid artery procedures. We describe 5 patients who underwent major head and neck procedures not requiring carotid ligation and who postoperatively suffered strokes. These occurred between the first and ninth postoperative days. Four of the patients were thought to have had emboli, 3 to the cerebral hemispheres (2 ipsilateral and 1 contralateral to the neck dissections), and another to the lower brain stem. Hypoperfusion was thought to have caused the stroke in the fifth patient. All patients had risk factors for stroke. The cases in our series were difficult to diagnose because of the delayed onset and subtle nature of symptoms, as well as masking of speech and communication due to the operative involved. Thrombogenesis within the internal carotid and vertebral artery systems due to patient positioning and intraoperative cervical manipulation may be an important etiologic factor in this form of stroke.