Stroke is the second cause of death and is a leading cause of serious long-term disability worldwide. Approximately 800,000 people in the United States have a stroke each year, of which 88% are ischemic and 12% are hemorrhagic. The most important risk factors for stroke include older age, atrial fibrillation, hypertension, and prior stroke. Other important risk factors include dyslipidemia, diabetes, smoking, and chronic kidney disease. This chapter discusses a common cerebrovascular accident case presentation of an acute ischemic stroke and the current strategies to best handle perioperative risk on these patients.
This chapter addresses the following:
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Ischemic stroke
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Hemorrhagic stroke
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Acute stroke
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Secondary stroke prevention
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Antiplatelets
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Oral anticoagulation
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Perioperative stroke
CC
A 65-year-old male with periodontal disease and multiple vascular factors is who is scheduled for teeth extractions next month presents to a hospital with a new onset of stroke symptoms.
HPI
The patient had a new sudden onset of slurred speech, right facial droop, and right-sided weakness. He was taken to the nearest emergency department. He was evaluated within the first 3 hours of the onset of his symptoms.
PMHX/PDHX/medications/allergies/SH/FH
The patient has a history of coronary arterial disease, diabetes mellitus type II, hypertension, and hyperlipidemia. He has two cardiac stents placed 5 years earlier. He is currently taking losartan, metoprolol, aspirin, metformin, and atorvastatin. He has no known drug allergies. The patient has a 30-pack-year history of smoking; he quit smoking 5 years ago. He drinks socially and denies illicit drug use.
Examination
General. The patient is a well-nourished, well-developed male in no apparent distress.
Vital signs . The patient’s blood pressure is 166/97 mm Hg, heart rate is irregular at 77 bpm, respiratory rate is 17 breaths per minute, and temperature is 36.5°C.
Maxillofacial. Normocephalic. The skin is dry and intact. The pupils are equal, round, and reactive to light and accommodation. There is no scleral icterus. Visual acuity is grossly intact. The external auditory canals are clear bilaterally, the tympanic membranes are intact, and the nares are patent. The patient has a right central facial droop (the forehead and orbicularis are spared) and mild dysarthria (cranial nerves [CNs] VII and X). CNs II through XII are grossly intact bilaterally. The neck is supple and without lymphadenopathy.
Intraoral. The mucosa is moist and pink. No ulcers, masses, or discolorations of the oral cavity are noted. There five absent teeth. Generalized severe periodontal disease is noted with root exposure on several teeth.
Cardiovascular. Irregular rhythm. No extra sounds. Positive left carotid bruit. Peripheral pulses present.
Pulmonary. Normal inspiration expiration sounds. No wheezes or rhonchi.
Abdominal. Soft and tender.
Neurologic: Awake, Alert, Oriented times two (AAOX2) normal attention, disoriented to time. Language: decrease on fluency with poor repetition, fair comprehension, and poor naming. Memory: unable to assess verbal memory because of aphasia. Mood: adequate.
Motor. There is right pronator drift of outstretched arms. Muscle bulk and tone are normal.
Strength. Strength is 4 of 5 on the right arm and leg and full otherwise. Reflexes: 2+ and symmetric at the biceps, triceps, knees, and ankles. Plantar response is extensor on the right and flexor on the left. Sensory: decreased to light touch; pinprick on the right. Position sense and vibration sense are intact in the fingers and toes.
Coordination. There is right dysmetria on finger-to-nose test. There are no abnormal or extraneous movements.
Gait. The gait is paretic and unsteady ( Fig. 107.1 ).
Imaging
Initial head computed tomography (CT) scan did not show any acute ischemia or any hemorrhage. CT angiography of his head showed an acute occlusion of the left distal middle cerebral artery.
Ischemic strokes are commonly caused by intracranial vessels occlusions, and hemorrhagic stroke are caused by either intracranial or subarachnoid vessel rupture. Only head CT or brain magnetic resonance imaging can discriminate between ischemic or hemorrhagic stroke.
Labs
The patient’s complete cell count was within normal limits. Coagulation panel was normal. Glucose was elevated at 255 mg/dL, and HbA1C was 8.5%; all other basic metabolic panel laboratory values were within normal limits. The electrocardiogram showed atrial fibrillation.
Assessment
Acute ischemic stroke symptoms in the setting of new-onset atrial fibrillation, multiple vascular risk factors, and an acute left middle cerebral artery occlusion.
Treatment
Treatment of patients with ischemic stroke includes emergent use of thrombolytic therapy, catheter-based thrombectomy guided by cerebral angiography, and use of anticoagulants or antiplatelets. Conversely, patients with hemorrhagic strokes may require emergent neurosurgical intervention, tight blood pressure control, and avoidance of anticoagulants and antiplatelets.
All patients with acute stroke should admitted to hospitals equipped with stroke units. Patients with subarachnoid hemorrhages and large ischemic or hemorrhagic strokes usually require intensive care units (ICUs) proficient in neurocritical care.
Thrombolytic therapy and thrombectomy for acute ischemic stroke are very effective therapies in reversing acute ischemic stroke symptoms, with number needed to treat of 1:7 and 1:3, respectively. However, the effectiveness of these treatments is time dependent. For instance, thrombolytic therapy for ischemic stroke can be only given within 4.5 hours of the onset of the symptoms. Hence, patients with acute stroke symptoms should get emergent attention and be transported to the closest stroke center without delays. Medical evaluation of stroke requires management of risk factors, stroke complications, and a comprehensive medical evaluation to determine the etiology of the stroke.
Transient ischemic attacks (TIAs) are cerebral ischemic events that typically resolve within 1 hour of their onset. Although they do not require acute thrombolytic therapies or thrombectomy, an emergent or urgent evaluation is warranted to prevent any future stroke event. Having a TIA carries a high risk of ischemic stroke within 3 months of the event.
This patient with acute ischemic stroke received both intravenous tissue plasminogen activator tPA and thrombectomy. He was next admitted to the ICU. His symptoms almost fully resolved the next day with the exception of mild paraphasic errors and word-finding difficulties. He was started on Eliquis for secondary stroke prevention and was discharged to home on his previous medications plus Eliquis. As per the following discussion, the patient’s dental procedure should be postponed, and anticoagulation should be continued.
Secondary stroke prevention treatments. Antithrombotic therapy, including antiplatelet or anticoagulant agents, is recommended for nearly all patients without contraindications. Dual antiplatelet therapy is recommended only for the short term in very specific patients, including those with minor strokes, high-risk TIAs, and severe symptomatic intracranial stenosis. Statins should be started in all patients with ischemic stroke or TIA and low-density lipoprotein greater than 70 mg/dL. Anticoagulation with Coumadin or direct-acting oral anticoagulants (DOACs) is recommended if the patient has atrial fibrillation and no significant contraindications. Internal carotid artery stenosis is an important and treatable cause of stroke. Patients with severe stenosis or more than 70% ipsilateral to a nondisabling stroke or TIA should be evaluated for urgent carotid endarterectomy or carotid artery stenting early after the stroke. Use of stents is not recommended intracranially. It is considered medically reasonable to percutaneously close a patent foramen ovale in stroke patients between 18 and 60 years of age with embolic stroke of undetermined source (ESUS) etiology and large shunts.
Discussion
Stroke types and risk factors
Recommendations for prevention strategies often depend on the specific subtype of TIA or stroke. First steps to determine to the cause of stroke come from the evaluation of brain imaging, vascular imaging, and cardiac evaluation. These are usually performed during the hospital stay. The cause of stroke typically is classified into large vessel, small vessel, cardiogenic, and cryptogenic. ESUS is a stroke that appears to be a non–small vessel type on neuroimaging but without an obvious source after a minimum standard evaluation, which includes cerebrovascular imaging, echocardiography, extended rhythm monitoring, and key laboratory studies such as a lipid profile and HbA1c.
For any stroke subgroup, management of vascular risk factors remains extremely important for secondary stroke prevention. Management of risk factors includes but is not limited to diabetes control, smoking cessation, lowering lipids, and especially controlling hypertension. Lifestyle factors, including healthy diet and physical activity, are also important for preventing a second stroke. Low-salt and Mediterranean diets are recommended for stroke risk reduction. Intensive medical management produces better results.
Invasive procedures and acute cerebrovascular events
There is a positive association between periodontitis and cerebrovascular disease found in multiple epidemiologic studies. Inflammatory markers, bacteremia, and development of atherosclerosis have been postulated as potential mechanism for these epidemiologic findings. Effective treatment of periodontitis does improve oral health and resolve systemic inflammation. However, there is insufficient evidence to support or refute the potential benefit of the treatment of periodontitis in preventing stroke.
Many oral surgical interventions aim to resolve acute and chronic oral infections. However, in theory, dental procedures could trigger an acute host response with local inflammation, microbial dissemination, and systemic inflammation. Then there is a presumptive small risk of stroke associated with certain oral surgical procedures. This risk is generally very low. People with certain medical conditions, such as heart disease or a history of stroke, may be at increased risk for stroke during dental procedures.
Theoretically, manipulation of an inflamed oral cavity might create exposure of inflammatory markers, transient bacteremia, and transient thrombophilia, increasing the risk of cardiovascular events, including stroke ( Fig. 107.2 ). However, current evidence does not support that invasive dental procedures such as extractions increase the risk of acute vascular events during the first 8 weeks after treatment.
