Exam 3 - Neuro Flashcards
Cerebral Perfusion Pressure (CPP) is calculated by:
A) CPP = MAP - ICP
B) CPP = CBF + ICP
C) CPP = MAP + CBF
D) CPP = ICP - MAP
Answer: A) CPP = MAP - ICP.
Rationale: CPP is the net pressure gradient causing cerebral blood flow to the brain (cerebral perfusion). It is calculated by subtracting the intracranial pressure (ICP) from the mean arterial pressure (MAP).
Which of the following would likely cause an increase in cerebral blood flow?
A) Decreased arterial carbon dioxide (PaCO2)
B) Increased arterial carbon dioxide (PaCO2)
C) Decreased arterial oxygen (PaO2)
D) Both B and C
Answer: D) Both B and C.
Rationale: An increase in PaCO2 leads to cerebral vasodilation and increased blood flow. Additionally, a decrease in PaO2 below certain thresholds can also trigger cerebral vasodilation to increase blood flow and oxygen delivery.
Autoregulation of cerebral blood flow ensures that the CBF remains constant over a range of:
A) 10-20 mmHg of mean arterial pressure
B) 20-40 mmHg of mean arterial pressure
C) 50-150 mmHg of mean arterial pressure
D) 150-200 mmHg of mean arterial pressure
Answer: C) 50-150 mmHg of mean arterial pressure.
Rationale: Cerebral autoregulation is a mechanism that maintains a relatively constant cerebral blood flow despite changes in systemic arterial pressure, usually within the range of 50-150 mmHg of mean arterial pressure.
CBF is approx 50 mL/100g brain tissue per minute
750mL/min
What percentage of cardiac output (COP) is typically received by the brain?
A) 5%
B) 15%
C) 20%
D) 25%
Answer: B) 15%.
Rationale: The brain receives about 15% of cardiac output, which is a substantial amount considering its size relative to the rest of the body, reflecting its high metabolic demand.
Which components are found within the intracranial vault?
A. Neural tissue, blood, and cerebrospinal fluid
B. Muscles, blood, and cerebrospinal fluid
C. Neural tissue, lymph, and synovial fluid
D. Bones, muscles, and neural tissue
Answer: A. Neural tissue, blood, and cerebrospinal fluid
Rationale: The intracranial vault contains neural tissue (including the brain and spinal cord), blood, and cerebrospinal fluid, which are all enclosed by the dura mater and bone.
According to the Monroe-Kellie hypothesis, what occurs if there is an increase in one component of the intracranial volume?
A. Intracranial pressure will always increase.
B. It must be offset by a decrease in another component to prevent an elevated intracranial pressure.
C. The intracranial pressure decreases in a compensatory manner.
D. It does not affect the intracranial pressure.
Answer: B. It must be offset by a decrease in another component to prevent an elevated intracranial pressure.
Rationale: The Monroe-Kellie hypothesis suggests that because the total volume inside the cranial cavity is fixed, an increase in any one of the components—neural tissue, blood, or cerebrospinal fluid—must be compensated for by a decrease in volume of another component to maintain a normal intracranial pressure.
What could be the result if homeostatic mechanisms fail to compensate for increased intracranial pressure?
A. Decreased mean arterial pressure
B. Increased cerebrospinal fluid production
C. Cerebral ischemia
D. Unchanged cerebral perfusion pressure
Answer: C. Cerebral ischemia
Rationale: Cerebral perfusion pressure is determined by the mean arterial pressure and intracranial pressure. Homeostatic mechanisms can increase mean arterial pressure to support cerebral perfusion pressure despite increases in intracranial pressure. However, if these compensatory mechanisms fail, it could lead to decreased blood flow to the brain, resulting in cerebral ischemia.
Which meningeal structure separates the two cerebral hemispheres?
A. Falx cerebri
B. Tentorium cerebelli
C. Arachnoid mater
D. Pia mater
Answer: A. Falx cerebri
Rationale: The falx cerebri is a sickle-shaped fold of dura mater that descends vertically in the longitudinal fissure between the two cerebral hemispheres.
The tentorium cerebelli is significant because it:
A. Divides the cerebrum from the cerebellum.
B. Protects the brainstem.
C. Is the primary site of cerebrospinal fluid production.
D. Contains the majority of the cerebral arteries.
Answer: A. Divides the cerebrum from the cerebellum.
Rationale: The tentorium cerebelli is an extension of the dura mater that separates the cerebrum from the cerebellum and marks the boundary between the supratentorial and infratentorial spaces.
What is a potential consequence of localized increases in intracranial content?
A. Decreased mean arterial pressure.
B. Herniation of brain tissue into another compartment.
C. Reduced cerebrospinal fluid production.
D. Atrophy of the cerebral hemispheres.
Answer: B. Herniation of brain tissue into another compartment.
Rationale: An increase in the content of one region of the brain can cause a regional increase in intracranial pressure, leading to the herniation of brain tissue into another compartment, especially if the increase is significant or sudden.
Herniation syndromes are categorized by:
A. The initial cause of increased intracranial pressure.
B. The patient’s age and medical history.
C. The specific type of brain tissue that is herniating.
D. The region of the brain that is affected.
Answer: D. The region of the brain that is affected.
Rationale: Herniation syndromes are classified based on the region of the brain affected by the herniation, which is important for diagnosis and management of the condition.
What is a characteristic clinical manifestation of subfalcine herniation?
A. Ipsilateral oculomotor nerve dysfunction
B. Midline shift and compression of the anterior cerebral artery branches
C. Medullary dysfunction
D. Respiratory instability
Answer: B. Midline shift and compression of the anterior cerebral artery branches
Rationale: Subfalcine herniation occurs when there is a herniation of the cerebral hemispheric contents beneath the falx cerebri, which often leads to a midline shift and compression of the branches of the anterior cerebral artery.
Uncal herniation, a subtype of transtentorial herniation, typically presents with:
A. Pupillary dilatation, ptosis, and lateral deviation of the affected eye
B. Bilateral oculomotor nerve palsy
C. Compression of the posterior cerebral artery branches
D. Decerebrate posturing
Answer: A. Pupillary dilatation, ptosis, and lateral deviation of the affected eye
Rationale: Uncal herniation occurs when the uncal region (medial portion of the temporal lobe) herniates over the tentorium cerebelli, leading to ipsilateral oculomotor nerve dysfunction, which can manifest as pupillary dilatation, ptosis, and lateral deviation of the affected eye. These symptoms reflect the involvement of cranial nerve III.
Herniation of the cerebellar tonsils through the foramen magnum can lead to:
A. Oculomotor nerve palsy
B. Medullary dysfunction and cardiorespiratory instability
C. Bilateral ptosis
D. Coma without brainstem involvement
Answer: B. Medullary dysfunction and cardiorespiratory instability
Rationale: Herniation of the cerebellar tonsils into the foramen magnum can lead to compression of the brainstem, particularly the medulla oblongata, which is responsible for regulating vital functions. This compression can result in medullary dysfunction and cardiorespiratory instability, which are life-threatening conditions.
Transtentorial herniation can result in all of the following EXCEPT:
A. Alteration in mental status (AMS)
B. Hemodynamic compromise
C. Respiratory compromise
D. Increased intracranial pressure without symptoms
Answer: D. Increased intracranial pressure without symptoms
Rationale: Transtentorial herniation results in herniation of the supratentorial contents past the tentorium cerebelli, leading to significant clinical symptoms including alteration in mental status, hemodynamic and respiratory compromise. It does not occur without symptoms; increased intracranial pressure in the context of herniation is associated with significant clinical manifestations.
How do tumors typically lead to increased intracranial pressure (ICP)?
A. By secreting cerebrospinal fluid
B. By causing edema in surrounding brain tissue
C. By decreasing cerebral blood flow
D. By reducing cerebral metabolic demand
Answer: B. By causing edema in surrounding brain tissue
Rationale: Tumors can lead to increased ICP not only due to their size but also by causing edema in the surrounding brain tissue. Additionally, they can obstruct the flow of cerebrospinal fluid, particularly if they involve the third ventricle.
Intracranial hematomas increase intracranial pressure in a manner similar to:
A. Ischemic strokes
B. Mass lesions
C. Encephalitis
D. Meningitis
Answer: B. Mass lesions
Rationale: Intracranial hematomas act like mass lesions, increasing ICP due to their volume and associated swelling. This is similar to the effect of tumors and other space-occupying lesions within the intracranial vault.
Subarachnoid hemorrhage can exacerbate increased intracranial pressure through:
A. Increased cerebral metabolic rate
B. Obstruction of cerebrospinal fluid reabsorption
C. Hypersecretion of cerebrospinal fluid
D. Compression of the cerebral aqueduct
Answer: B. Obstruction of cerebrospinal fluid reabsorption
Rationale: Blood in the cerebrospinal fluid, as seen in subarachnoid hemorrhage, can lead to obstruction of CSF reabsorption, which can exacerbate increased ICP. Additionally, granulations from the inflammatory response can further impair CSF flow.
Infections such as meningitis or encephalitis contribute to increased intracranial pressure primarily by:
A. Promoting cerebrospinal fluid production
B. Causing edema or obstruction of cerebrospinal fluid reabsorption
C. Inducing vasospasm of cerebral arteries
D. Decreasing blood-brain barrier integrity
Answer: B. Causing edema or obstruction of cerebrospinal fluid reabsorption
Rationale: Infections like meningitis or encephalitis can lead to increased ICP due to edema from inflammatory processes or by obstructing CSF reabsorption, often as a result of the inflammatory response within the subarachnoid space or the ventricular system.
What is the rationale behind elevating the head to decrease intracranial pressure?
A. It reduces cerebrospinal fluid production.
B. It encourages jugular venous outflow.
C. It increases cerebral perfusion pressure.
D. It enhances cerebrospinal fluid absorption.
Answer: B. It encourages jugular venous outflow.
Rationale: Elevating the head of the bed is a non-pharmacological method used to facilitate venous drainage from the head, which can help reduce intracranial pressure.
Hyperosmotic drugs decrease intracranial pressure by:
A. Reducing cerebral metabolic demand.
B. Increasing cerebrospinal fluid production.
C. Increasing osmolarity, drawing fluid across the blood-brain barrier.
D. Vasoconstriction of cerebral blood vessels.
Answer: C. Increasing osmolarity, drawing fluid across the blood-brain barrier.
Rationale: Hyperosmotic drugs, such as mannitol, work to reduce intracranial pressure by creating an osmotic gradient that draws fluid from the brain parenchyma, across the blood-brain barrier, into the bloodstream.
Which medication can be used to decrease intracranial pressure by reducing cerebral metabolic oxygen consumption?
A. Antibiotics
B. Antiepileptics
C. Corticosteroids
D. Cerebral vasoconstricting anesthetics (e.g., propofol)
Answer: D. Cerebral vasoconstricting anesthetics (e.g., propofol)
Rationale: Cerebral vasoconstricting anesthetics like propofol can decrease cerebral metabolic oxygen consumption (CMRO2) and cerebral blood flow (CBF), which can contribute to a reduction in intracranial pressure.
An external ventricular drain (EVD) is utilized in the management of increased ICP primarily to:
A. Monitor cerebral blood flow.
B. Drain cerebrospinal fluid.
C. Administer medications directly to the central nervous system.
D. Reduce cerebral edema through refrigeration.
Answer: B. Drain cerebrospinal fluid.
Rationale: An external ventricular drain is used to directly remove cerebrospinal fluid from the ventricular system to help manage increased intracranial pressure.
What is the first step in conducting a neurological assessment for anesthesia planning?
A. Administering preoperative medications
B. Knowing the basic pathophysiology of neurological disorders
C. Reviewing the patients’ drug history
D. Deciding on the anesthetic plan
Answer: B. Knowing the basic pathophysiology of neurological disorders
Rationale: Understanding the basic pathophysiology of neurological disorders is essential as it guides the assessment of the patient’s history, symptoms, baseline neuro-deficits, and helps in the interpretation of imaging and neurologic test results, which are fundamental in planning anesthesia care.
Why is it important to review a patient’s current medications during a neurological assessment before anesthesia?
A. To identify potential drug interactions with anesthesia
B. To comply with hospital protocol
C. To prepare the medication chart for surgery
D. To educate the patient about their medications
Answer: A. To identify potential drug interactions with anesthesia
Rationale: Reviewing a patient’s current medications is crucial to identify any potential interactions with anesthetic drugs, as well as to understand the patient’s existing treatments which might affect perioperative management and anesthetic choices.
What is the purpose of implementing preoperative measures in patients with neurological issues?
A. To complete the required paperwork before surgery
B. To optimize the patients’ condition prior to anesthesia
C. To ensure the patient has fasted appropriately
D. To administer preoperative sedation
Answer: B. To optimize the patients’ condition prior to anesthesia
Rationale: Preoperative measures are often necessary to stabilize and optimize the patient’s condition before administering anesthesia, especially in those with neurological deficits. This may include adjusting medications, hydration status, or other interventions specific to the patient’s neurological condition.
When documenting a preoperative plan for a patient with a neurological condition, what is essential to include?
A. Only the chosen anesthetic technique
B. A detailed medical history irrelevant to the surgery
C. The rationale for the chosen anesthetic plan
D. An exhaustive list of all possible anesthetic drugs
Answer: C. The rationale for the chosen anesthetic plan
Rationale: Providing clear documentation of the neurological assessment, including the rationale for the chosen anesthetic plan, is important for communication among the healthcare team and for medico-legal reasons. It should reflect the integration of the patient’s history, current condition, risks, and benefits of the anesthetic options considered.
Which patient demographic is more commonly diagnosed with Multiple Sclerosis (MS)?
A. Males aged 50-70
B. Females aged 20-40
C. Females over the age of 60
D. Males in their teenage years
Answer: B. Females aged 20-40
Rationale: Multiple Sclerosis typically has an onset age between 20-40 years and is more prevalent in females.
Which of the following is considered a trigger for exacerbation in patients with Multiple Sclerosis (MS)?
A. Low-stress levels
B. Cooler body temperatures
C. The postpartum period
D. Increased physical activity
Answer: C. The postpartum period
Rationale: Triggers for periods of exacerbation in Multiple Sclerosis include stress, elevated temperatures, and the postpartum period. These can lead to a flare-up of symptoms.
What is a common symptom of Multiple Sclerosis (MS) that varies based on the site of demyelination?
A. Consistent pain in the lower extremities
B. Motor weakness
C. Uniform loss of vision in both eyes
D. Steady cognitive decline
Answer: B. Motor weakness
Rationale: The symptoms of Multiple Sclerosis vary based on the location of demyelination and can include motor weakness, sensory disorders, visual impairment, and autonomic instability. Motor weakness is particularly influenced by the site of the nerve damage.
The management of Multiple Sclerosis (MS) often includes the use of:
A. Corticosteroids and immune modulators
B. Antibiotics and antivirals
C. Antidepressants and mood stabilizers
D. Chemotherapy and radiation therapy
Answer: A. Corticosteroids and immune modulators
Rationale: While there is no cure for Multiple Sclerosis, management includes the use of corticosteroids to reduce inflammation during exacerbations and immune modulators to alter the course of the disease, along with targeted antibodies.
In patients with Multiple Sclerosis undergoing surgery, why is temperature management considered critical?
A. Increase in body temperature can precipitate an exacerbation of MS symptoms.
B. Lower body temperature reduces the effectiveness of anesthetic agents.
C. Higher body temperature increases the risk of intraoperative bleeding.
D. Lower body temperature may prolong the duration of muscle relaxants.
Answer: A. Increase in body temperature can precipitate an exacerbation of MS symptoms.
Rationale: Patients with MS can experience worsening of symptoms with increased body temperature, known as Uhthoff’s phenomenon. Therefore, careful temperature management is essential to avoid triggering an exacerbation of MS symptoms.
What is an important consideration when providing anesthesia to MS patients with a history of long-term steroid use?
A. They should always be given supplemental oxygen.
B. They may require a stress-dose of steroids due to adrenal suppression.
C. They must be administered a lower dose of anesthetic agents.
D. They should receive an increased dose of muscle relaxants.
Answer: B. They may require a stress-dose of steroids due to adrenal suppression.
Rationale: Long-term steroid use can lead to adrenal suppression. Administering a stress-dose of steroids may be necessary for patients with MS who have been on long-term steroids to provide the body with sufficient cortisol to handle the stress of surgery.
Why should succinylcholine be avoided in patients with Multiple Sclerosis?
A. It may precipitate malignant hyperthermia.
B. It can cause bradycardia and hypotension.
C. It may induce hyperkalemia due to upregulated nicotinic acetylcholine receptors.
D. It can result in prolonged paralysis post-operatively.
Answer: C. It may induce hyperkalemia due to upregulated nicotinic acetylcholine receptors.
Rationale: In MS patients, there can be an upregulation of nicotinic acetylcholine receptors, which makes them more susceptible to the potassium-releasing effects of succinylcholine, potentially leading to hyperkalemia. Therefore, this drug is best avoided in these patients.
What preoperative assessment is especially important in patients with MS who exhibit respiratory compromise?
A. Electrocardiogram (ECG)
B. Pulmonary function tests (PFTs)
C. Complete metabolic panel (CMP)
D. Echocardiogram (ECHO)
Answer: B. Pulmonary function tests (PFTs)
Rationale: For MS patients with respiratory compromise, assessing respiratory function with pulmonary function tests is crucial to understanding the patient’s baseline respiratory status and potential anesthetic risks, as well as to guide intraoperative and postoperative respiratory management.
Myasthenia Gravis (MG) is characterized by muscle weakness that is:
A. Persistent and unchanging throughout the day.
B. Exacerbated with exercise and improves with rest.
C. Unaffected by physical activity levels.
D. Improved with exercise as muscles warm up.
Answer: B. Exacerbated with exercise and improves with rest.
Rationale: MG is an autoimmune disorder where antibodies impair neurotransmission at the neuromuscular junction, leading to muscle weakness that worsens with exercise and improves with rest.
Which cranial nerve involvement in Myasthenia Gravis (MG) can lead to respiratory insufficiency?
A. Olfactory nerve involvement leading to smell deficits.
B. Optic nerve involvement affecting vision.
C. Bulbar involvement leading to laryngeal and pharyngeal muscle weakness.
D. Trigeminal nerve involvement causing mastication difficulties.
Answer: C. Bulbar involvement leading to laryngeal and pharyngeal muscle weakness.
Rationale: The bulbar muscles, when affected by MG, can lead to weakness of the laryngeal and pharyngeal muscles, resulting in difficulties with swallowing and the potential for respiratory insufficiency due to aspiration risks. glossopharyngeal nerve (CN IX), the vagus nerve (CN X), the accessory nerve (CN XI), and the hypoglossal nerve (CN XII).
The treatment for Myasthenia Gravis (MG) commonly includes the use of:
A. Acetylcholinesterase inhibitors to decrease the availability of acetylcholine.
B. Acetylcholinesterase inhibitors to increase the availability of acetylcholine.
C. Beta-blockers to manage cardiac symptoms.
D. Anticholinergic drugs to reduce excessive muscle contractions.
Answer: B. Acetylcholinesterase inhibitors to increase the availability of acetylcholine.
Rationale: Acetylcholinesterase inhibitors, such as Pyridostigmine, are used in the treatment of MG to inhibit the breakdown of acetylcholine, thereby increasing its availability and improving neuromuscular transmission.
In the management of Myasthenia Gravis (MG), thymectomy is associated with:
A. Worsening of symptoms in most patients.
B. No change in symptoms for the majority of patients.
C. Improvement in symptoms in about 90% of patients.
D. Complete cure in all patients.
Answer: C. Improvement in symptoms in about 90% of patients.
Rationale: Thymectomy, the surgical removal of the thymus gland, can lead to an improvement in symptoms for about 90% of patients with MG. Although not all patients will achieve remission, many will experience a reduction in their symptoms.
Why is it important to reduce paralytic dosage in patients with Myasthenia Gravis (MG) during anesthesia?
A. To minimize the risk of malignant hyperthermia.
B. To avoid prolonged muscle weakness postoperatively.
C. To reduce the chances of an allergic reaction to anesthetic drugs.
D. To prevent the risk of intraoperative awareness.
Answer: B. To avoid prolonged muscle weakness postoperatively. (I DONT LIKE THIS SLIDE)
Rationale: Patients with MG are particularly sensitive to neuromuscular blocking agents due to their pre-existing neuromuscular junction dysfunction. Reducing the dosage of paralytics can help prevent exacerbation of muscle weakness and respiratory compromise postoperatively.
Acetylcholinesterase inhibitors used to treat MG can have an interaction with which types of drugs?
A. Beta-blockers
B. Local anesthetics, specifically esters
C. Nonsteroidal anti-inflammatory drugs (NSAIDs)
D. Antibiotics
Answer: B. Local anesthetics, specifically esters
Rationale: Acetylcholinesterase inhibitors may prolong the action of succinylcholine and ester local anesthetics due to their mechanism of increasing acetylcholine at the neuromuscular junction, which can lead to prolonged neuromuscular blockade.
In a patient with Myasthenia Gravis, the purpose of considering preoperative steroids is to:
A. Provide analgesia.
B. Manage the autoimmune process during surgery.
C. Reduce inflammation related to the surgical procedure.
D. Compensate for adrenal suppression in long-term steroid users.
Answer: D. Compensate for adrenal suppression in long-term steroid users.
Rationale: Patients with MG who have been on long-term steroid therapy may have adrenal suppression. Considering preoperative steroids is important to prevent adrenal crisis during the stress of surgery.
What is a crucial part of preoperative counseling for patients with Myasthenia Gravis?
A. Warning about the potential for chronic pain postoperatively.
B. Discussing the increased risk of needing postoperative respiratory support.
C. Informing about the likelihood of extended hospital stay for observation.
D. Advising on dietary restrictions post-surgery.
Answer: B. Discussing the increased risk of needing postoperative respiratory support.
Rationale: Due to the potential for exacerbation of muscle weakness, patients with MG should be counseled about the increased risk of requiring postoperative respiratory support or ventilation until they have fully recovered from anesthesia.
Eaton-Lambert Syndrome is often associated with which of the following conditions?
A. Breast cancer
B. Small cell lung carcinoma
C. Lymphoma
D. Prostate cancer
Answer: B. Small cell lung carcinoma
Rationale: More than 60% of cases of Eaton-Lambert Syndrome are associated with small cell lung carcinoma. It is a paraneoplastic syndrome that can precede or coincide with the diagnosis of lung cancer.
What is the primary mechanism by which Eaton-Lambert Syndrome reduces the efficacy of neuromuscular transmission?
A. It enhances the degradation of acetylcholine in the synaptic cleft.
B. It reduces calcium influx into the presynaptic terminals.
C. It blocks the postsynaptic acetylcholine receptors.
D. It increases the release of acetylcholine into the synaptic cleft.
Answer: B. It reduces calcium influx into the presynaptic terminals.
Rationale: Eaton-Lambert Syndrome involves the development of autoantibodies against voltage-gated calcium channels, leading to reduced calcium influx into the presynaptic nerve terminals, which decreases the release of acetylcholine at the neuromuscular junction.
Which medication is used in the treatment of Eaton-Lambert Syndrome to facilitate the release of acetylcholine at the neuromuscular junction?
A. Acetylcholinesterase inhibitors
B. Selective potassium channel blockers such as 3,4-diaminopyridine
C. Beta-blockers
D. Calcium channel blockers
Answer: B. Selective potassium channel blockers such as 3,4-diaminopyridine
Rationale: Treatment for Eaton-Lambert Syndrome may include the use of selective potassium channel blockers like 3,4-diaminopyridine, which increases acetylcholine release and improves muscle strength.
Lambert-Eaton syndrome is characterized by which of the following mechanisms?
A. Excessive acetylcholine release at the neuromuscular junction.
B. Antibodies against postsynaptic acetylcholine receptors.
C. Antibodies against the presynaptic calcium channels of the neuromuscular junction.
D. Degeneration of the presynaptic nerve terminals.
Answer: C. Antibodies against the presynaptic calcium channels of the neuromuscular junction.
Rationale: Lambert-Eaton syndrome involves an autoimmune response where antibodies target the presynaptic calcium channels at the neuromuscular junction, leading to decreased acetylcholine release and impaired muscular transmission.
The symptoms of Lambert-Eaton syndrome may improve with:
A. Rest and inactivity.
B. Cooling therapies such as cryotherapy.
C. Repeated muscle use.
D. Administration of calcium channel activators.
Answer: C. Repeated muscle use.
Rationale: An atypical feature of Lambert-Eaton syndrome is that muscle strength may transiently improve with repeated use, known as ‘facilitation,’ which is opposite to the fatigue seen in myasthenia gravis.
Patients with Eaton-Lambert Syndrome (ELS) exhibit increased sensitivity to which types of agents?
A. Non-depolarizing neuromuscular blockers (ND-NMBs) and depolarizing neuromuscular blockers (D-NMBs)
B. General anesthetics and benzodiazepines
C. Local anesthetics and sedatives
D. Anticholinesterase medications and antibiotics
Answer: A. Non-depolarizing neuromuscular blockers (ND-NMBs) and depolarizing neuromuscular blockers (D-NMBs)
Rationale: Patients with ELS are very sensitive to both ND-NMBs and D-NMBs due to the pre-existing compromised neuromuscular transmission. They are significantly more sensitive to ND-NMBs compared to patients with Myasthenia Gravis (MG).
What is a hallmark laboratory finding in Duchenne Muscular Dystrophy (DMD)?
A. Decreased serum creatine kinase levels.
B. Elevated serum creatine kinase levels.
C. Elevated white blood cell count.
D. Decreased hemoglobin levels.
Answer: B. Elevated serum creatine kinase levels.
Rationale: Duchenne Muscular Dystrophy is characterized by elevated serum creatine kinase levels due to muscle wasting. Creatine kinase is released into the bloodstream when muscle fibers are damaged, which is a frequent occurrence in DMD.
Duchenne Muscular Dystrophy primarily affects which population?
A. Girls and boys equally, onset in teenage years.
B. Only boys, typically with onset between 2-5 years of age.
C. Only girls, onset usually in early childhood.
D. Boys and girls with onset in infancy.
Answer: B. Only boys, typically with onset between 2-5 years of age.
Rationale: DMD is an X-linked disorder and therefore primarily affects boys, with symptoms typically becoming apparent between 2-5 years of age.
What is a common complication associated with the progression of Duchenne Muscular Dystrophy?
A. Hypertension.
B. Type II diabetes.
C. Cardiopulmonary complications.
D. Hyperthyroidism.
Answer: C. Cardiopulmonary complications.
Rationale: Cardiopulmonary complications are a significant cause of morbidity and the most common cause of death in patients with DMD, as the disease progresses to affect cardiac and respiratory muscles.
Why is Duchenne Muscular Dystrophy associated with skeletal changes such as kyphoscoliosis?
A. Vitamin D deficiency.
B. Genetic predisposition to bone deformities.
C. Progressive muscle wasting leading to skeletal deformities.
D. Overuse of affected muscles during physical therapy.
Answer: C. Progressive muscle wasting leading to skeletal deformities.
Rationale: In DMD, progressive muscle wasting can lead to imbalances in muscle support around the spine and long bones, resulting in deformities such as kyphoscoliosis and long bone fragility.
Why is it important to conduct a thorough cardiac evaluation, including an EKG and echocardiogram, in patients with Muscular Dystrophy before administering anesthesia?
A. Most patients with Muscular Dystrophy have congenital heart defects.
B. Muscular Dystrophy is commonly associated with the development of cardiomyopathy.
C. Anesthesia can cause bradycardia, which is especially risky in these patients.
D. Patients with Muscular Dystrophy are at a higher risk for developing myocardial infarction during surgery.
Answer: B. Muscular Dystrophy is commonly associated with the development of cardiomyopathy.
Rationale: Due to the potential for cardiac involvement, including cardiomyopathy in patients with Muscular Dystrophy, a preoperative cardiac workup is essential to assess the heart’s function and to tailor anesthetic management accordingly.
What is a potential consequence of using succinylcholine (Succs) in patients with Muscular Dystrophy?
A. It can lead to a hypermetabolic syndrome similar to malignant hyperthermia.
B. It can cause an unexpected allergic reaction specific to MD patients.
C. It will likely result in a prolonged duration of anesthesia.
D. It has no significant side effects or consequences in MD patients.
Answer: A. It can lead to a hypermetabolic syndrome similar to malignant hyperthermia.
Rationale: In patients with Muscular Dystrophy, the use of succinylcholine and volatile anesthetics can exacerbate muscle membrane instability and may trigger a hypermetabolic syndrome, with clinical features resembling malignant hyperthermia, which can be life-threatening.
What anesthetic strategy is preferred for patients with Muscular Dystrophy to avoid cardiopulmonary complications- select all?
A. Total Intravenous Anesthesia (TIVA) with low-dose rocuronium
B. High-dose volatile anesthetics
C. General anesthesia with high-dose non-depolarizing neuromuscular blockers
D. Regional anesthesia (RA) over general anesthesia (GA)
Answer: A. A. Total Intravenous Anesthesia (TIVA) with low-dose rocuronium & D. Regional anesthesia (RA) over general anesthesia (GA)
Rationale: Regional anesthesia is often preferred over general anesthesia for patients with Muscular Dystrophy to avoid triggering cardiopulmonary complications and to reduce the risk of malignant hyperthermia-like reactions.
What preoperative laboratory test is crucial for evaluating the extent of muscle wasting in Muscular Dystrophy?
A. Complete Blood Count (CBC)
B. Creatine Kinase (CK)
C. Blood Urea Nitrogen (BUN)
D. Aspartate Aminotransferase (AST)
Answer: B. Creatine Kinase (CK)
Rationale: Elevated serum creatine kinase levels are indicative of muscle wasting and are often found in patients with Muscular Dystrophy due to ongoing muscle damage. This test helps assess the severity of the disease.
What is myotonia?
A. A rapid onset of muscle weakness following activity.
B. An inability of muscles to relax promptly after voluntary contraction.
C. A type of muscular dystrophy affecting primarily the heart muscle.
D. A genetic disorder leading to involuntary muscle contractions.
Answer: B. An inability of muscles to relax promptly after voluntary contraction.
Rationale: Myotonia refers to a condition where there is a prolonged contraction or delayed relaxation of muscles following voluntary contraction, commonly seen in various muscle disorders including myotonic dystrophy.
Which muscles are typically spared in Myotonia Congenita?
A. Skeletal muscles
B. Smooth and cardiac muscles
C. Diaphragmatic muscles
D. Facial muscles
Answer: B. Smooth and cardiac muscles
Rationale: Myotonia Congenita is a milder form of myotonic disorder which typically involves the skeletal muscles, but spares the smooth and cardiac muscles.
What percentage of patients with Myotonic Dystrophy are reported to have mitral valve prolapse (MVP)?
A. 10%
B. 20%
C. 50%
D. 75%
Answer: B. 20%
Rationale: Myotonic Dystrophy can affect cardiac conduction and about 20% of individuals with this condition may have mitral valve prolapse. This has implications for anesthesia, particularly regarding cardiovascular stability.
Central Core Disease is characterized by what primary symptom?
A. Progressive muscle wasting in the face and hands
B. Difficulty swallowing and speaking
C. Proximal muscle weakness and scoliosis
D. Prolonged muscle stiffness after exercise
Answer: C. Proximal muscle weakness and scoliosis
Rationale: Central Core Disease is a rare genetic muscle disorder characterized by a deficiency in mitochondrial enzymes in core muscle cells, resulting in proximal muscle weakness and scoliosis.
Why is the assessment of GI motility important before administering anesthesia to patients with myotonic conditions?
A. To ensure proper nutrition before surgery.
B. To gauge the risk of aspiration due to GI hypomotility.
C. To determine the need for postoperative dietary restrictions.
D. To assess the patient’s ability to metabolize oral medications.
Answer: B. To gauge the risk of aspiration due to GI hypomotility.
Rationale: GI hypomotility can increase the risk of aspiration, a serious concern during anesthesia. Preoperative evaluation helps in planning for aspiration risk mitigation strategies.
Succinylcholine is avoided in patients with myotonic conditions primarily because:
A. It is less effective in these patients.
B. It can cause prolonged muscle relaxation.
C. It can trigger myotonic muscle contractions (fasciculations).
D. It increases the risk of malignant hyperthermia.
Answer: C. It can trigger myotonic muscle contractions (fasciculations).
Rationale: Succinylcholine may trigger myotonia, leading to prolonged and potentially severe muscle contractions, complicating intubation and ventilation.
Pre-anesthetic endocrine assessment for patients with myotonic conditions often includes which of the following?
A. Adrenal function tests.
B. Thyroid and glucose level checks.
C. Pituitary hormone profiling.
D. Parathyroid hormone measurements.
Answer: B. Thyroid and glucose level checks.
Rationale: There is a high incidence of endocrine abnormalities in myotonic conditions, particularly involving the thyroid and glucose levels, which can affect both anesthesia management and surgical outcomes.
Why should patients with myotonic conditions be kept warm during the perioperative period?
A. Cold exposure may decrease blood viscosity.
B. Warmth provides comfort and reduces anxiety.
C. Cold temperatures can exacerbate myotonic symptoms.
D. Warm temperatures enhance the effect of anesthetics.
Answer: C. Cold temperatures can exacerbate myotonic symptoms.
Rationale: Patients with myotonic conditions may experience worsening of myotonic symptoms when exposed to cold temperatures; hence, maintaining normothermia is crucial.
