Simulation Exam 4 Flashcards
In normal patients, an increase in the blood pressure from 120/45 to 180/90 results in:
Cerebral vasoconstriction
In this patient, the MAP increased from 70 to 120. Normally, the CBF remains constant between MAPs of 60 to 140 mmHg. As the MAP increases within this range, the cerebral vessels constrict to keep CBF constant.
Which of the following tests would be most appropriate for testing neural integrity during posterior fossa surgery?
Brainstem auditory evoked potentials
Brainstem auditory evoked potentials assess the integrity of the 8th cranial nerve and the auditory pathways above the pons. Somatosensory evoked potentials assess the dorsal spinal column and sensory cortex and are best for monitoring during spinal surgery, carotid endarterectomy, and aortic surgery. Visual evoked potentials assess the integrity of the optic nerve and upper brainstem and are best for monitoring during pituitary resection. The wake-up test assesses movement and evaluates the integrity of the motor tracts in the ventral spinal column.
The incidence of placental abruption is much higher in patients with
preeclampsia
Placental abruption is the separation of an implanted placenta after 20 weeks of pregnancy. It can result in massive blood loss and is one of the most common causes of fetal demise. If the abruption is mild, a vaginal delivery may be attempted, but at any sign of fetal distress an emergency cesarean section must be carried out. It is more common in patients with preeclampsia (up to 1 in 4).
A patient scheduled for repair of a fractured ulna following a fall has severe dementia. The patient’s daughter has power-of-attorney and asks if the patient could receive a brachial plexus block for postoperative pain control. The patient has a history of aortic valve stenosis, a platelet count of 158,000, a white cell count of 13,000, a blood pressure of 98/51, and a heart rate of 56 beats per minute. You tell the patient’s daughter that a brachial plexus block would not be recommended because:
The patient has dementia and is therefore unable to describe pain accurately
A patient with severe dementia may not be able to describe pain adequately, particularly pain on injection which could make the possibility of performing a damaging intraneural injection more likely. Also, many practitioners elicit paresthesias to correctly identify the appropriate site of injection and the patient may not be able to report paresthesias. Aortic valve stenosis and potential systemic infection are not contraindications to peripheral nerve blocks. Because the daughter has power-of-attorney, she would be able to provide consent on the patient’s behalf.
After performing a superficial cervical plexus block, the patient exhibits paralysis of the trapezius muscle on the same side. You know that this resulted from blocking the
accessory nerve
A superficial cervical plexus block is performed by injecting 5 mL of local anesthetic along the posterior aspect and medial surface of the sternocleidomastoid muscle. The accessory nerve may also be blocked during this procedure, resulting in temporary paralysis of the trapezius muscle on the same side.
What factors contribute to the development of nausea in patients who receive a subarachnoid block? (select two)
Hypotension & Opioid premedication
Nausea is more common in patients with a block higher than T5, those who have received opioid premedication, experience hypotension, or have a history of motion sickness.
Which of the following laboratory findings would be consistent with a diagnosis of hyperparathyroidism?
Serum calcium = 10.5 mg/dL
Hyperparathyroidism is the most common cause of hypercalcemia, which is defined as a serum calcium level greater than 10.4 mg/dL.
Which of the following conditions is not a complication of adenoidal and tonsillar hyperplasia?
Obligate nasal breathing
Adenoidal hyperplasia can result in nasopharyngeal obstruction resulting in obligate mouth breathing. Both adenoidal and tonsillar hyperplasia are linked to sleep apnea with the potential for cor pulmonale and failure to thrive.
You are evaluating a patient with chronic renal failure prior to surgery for an arteriovenous graft placement. Which of the following diagnostic findings would NOT be consistent with chronic renal failure?
Hypercalcemia
Hyperkalemia, hypocalcemia, hypermagnesemia, and hyperphosphatemia are common electrolyte abnormalities seen in chronic renal failure. Hypertension, dyslipidemia, and silent myocardial ischemia are also signs consistent with the diagnosis.
A patient with metabolic acidosis has a sodium of 145 mEq/L, a chloride of 104 mEq/L, and a bicarbonate level of 18 mEq/L. Which of the following would most likely be a cause of the acidosis?
Alcohol toxicity
This analysis requires knowledge of the anion gap, the formula for which is: [Na+] - ([Cl-] + [HCO3-]). In this instance, the anion gap is 23 mEq/L. The normal anion gap is 8 to 12 mEq/L (some sources cite 9 to 13 mEq/L). Causes of increased anion gap acidosis include renal failure, ketoacidosis, lactic acidosis, hyperosmolar nonketotic coma, alcohol toxicity, ingestion of salicylates, methanol, ethylene glycol, paraldehyde, toluene, and sulfur. Although the other options listed above can result in metabolic acidosis, alcohol toxicity is the only option associated with an increased anion gap.
Which of the following conditions is consistent with a diagnosis of adult respiratory distress syndrome?
Pulmonary artery wedge pressure less than 18 mmHg
For a patient to meet the diagnosis of Adult Respiratory Distress Syndrome (also known as Acute Respiratory Distress Syndrome), four criteria must be met: acute onset, PAO2 to FiO2 ratio <200 regardless of the level of PEEP applied, bilateral infiltrates on chest x-ray, and a PA wedge pressure less than or equal to 18 mmHg.
Which of the following statements regarding spinal shock is incorrect?
The profound hypotension seen with spinal shock is primarily due to diminished afterload
The profound hypotension seen with spinal shock is related to the level at which the lesion is located (cervical injuries produce more severe hypotension than do lumbar injuries) and is due primarily to a drop in preload caused by dilation of the capacitance vessels. A wide range of cardiac dysrhythmias ranging from PVCs to complete heart block are seen with spinal shock and the hemodynamic changes associated with spinal shock may last for up to 1-3 weeks after the injury occurs.
You are called to intubate a patient presenting to the emergency department with a spinal cord transection at C3. You would expect which of the following on first assessment:
Bradycardia
A patient with a spinal cord lesion at C3 would typically exhibit severe hypotension from dilation of the capacitance vessels due to loss of sympathetic tone and bradycardia from a lack of sympathetic input from the cardioacceleratory fibers of T1-T4. Due to the drop in preload, the patient would likely exhibit signs of fluid volume deficit which would translate into a decreased urine output.
Which of the following conditions is associated with the development of peripheral neuropathies? (Select two)
Porphyria & Diabetes
Diabetes mellitus, alcoholism, porphyria, multiple organ failure, and human immunodeficiency virus infection are all causes of peripheral neuropathies that may result in both sensory and motor dysfunction. Fanconi syndrome is the result of disorders of the proximal renal tubule which cause hyperaminoaciduria, glycosuria, and hyperphosphaturia. Renal azotemia describes damage to the renal tubules, interstitium, glomerulus, or renal vasculature that results in reductions in glomerular filtration rates and can lead to acute renal failure.
Which of the following is not true of patients with scleroderma?
Raynaud’s phenomenon is rarely associated with scleroderma
This question simulates the mixture of combination negative and double-negative scenarios that may appear on the nurse anesthesia exam and warrant close scrutiny to avoid confusion, especially in the high-stress period that accompanies an exam of this magnitude. In this example, all of the above statements are true except option A. Over 95% of patients with scleroderma experience Raynaud’s phenomenon.
