A 67-year-old man with past medical history of hypertension, diabetes mellitus, smoking, and recent diagnosis of small cell lung cancer is admitted to the ICU presents with complaints of nausea, vomiting, weakness, and altered mental status. On examination he is somnolent but opens his eyes to voice. He is not oriented to person or place. He appears well hydrated and his vital signs are within normal limits. His basic metabolic panel is notable for:
The patient has a seizure as you are examining him. After ensuring adequate oxygenation and ventilation the most appropriate next treatment is ?
Correct Answer: C
The patient presents with hyponatremia (serum Na <135 mEq/L) most likely secondary to syndrome of inappropriate antidiuretic hormone (SIADH) resulting from his lung cancer. Patients with hyponatremia and severe neurological symptoms (seizures, coma, inability communicate) should be treated with hypertonic saline. Left untreated, severe hyponatremia can lead to potentially lethal cerebral edema.
The SIADH is characterized by euvolemic hyponatremia, low serum osmolality (<280 mOsm/kg), and increased urine osmolality. Hyponatremia is secondary to antidiuretic hormone–induced retention of ingested water. Common causes of SIADH include malignancies (highest among patients with small-cell lung cancer), infections (pneumonia, meningitis, AIDS), medications, hormone deficiencies (hypothyroidism, adrenal insufficiency), neurological injuries (subarachnoid hemorrhage), and surgery.
Treatment of hyponatremia depends on the severity of the symptoms and the rapidity with which they develop. In asymptomatic patients, treatment of the underlying cause can correct hyponatremia. Fluid restriction is the mainstay of therapy in patients with SIADH without any neurological symptoms. Patients with neurological symptoms, and those with resistant hyponatremia, should be treated with intravenous hypertonic saline.
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A 63-year-old woman with a recent diagnosis of lung cancer is admitted to the ICU with hypotension, acute onset of chest pain, cough, and shortness of breath. Her vital signs are:
Chest X-ray is notable for a right lower lobe consolidation, as well as widened mediastinum. Chest computed tomography with contrast reveals a large pericardial effusion and transthoracic echocardiography shows a large pericardial effusion with diastolic collapse of the right ventricle.
Which of the following is next most appropriate therapeutic intervention at this time?
The patient presents with respiratory distress and hypotension secondary to pericardial effusion with tamponade physiology. Emergent echocardiography–guided pericardiocentesis will evacuate the pericardial effusion and relieve symptoms.
Pericardial effusions are common in patients with metastatic cancer. However, most cancer patients with pericardial effusions are asymptomatic. Symptoms develop in patients with large pericardial effusions or those with rapid fluid accumulation. Typical symptoms include cough, dyspnea, and chest pain. Physical examination findings are notable for hypotension, tachypnea, tachycardia, respiratory distress, jugular venous distension, and pulsus paradoxus. Chest X-ray may show widened mediastinum and EKG may show sinus tachycardia, low voltage, nonspecific ST/T changes, and electrical alternans. Echocardiography is the gold standard for diagnosing pericardial effusion. Tamponade physiology is characterized by diastolic collapse of the right ventricle, dilatation of inferior vena cava, and loss of respiratory variability in IVC diameter as well as pronounced ventricular interdependence with respiration.
Positive pressure ventilation reduces venous return (cardiac preload) and can lead to hemodynamic collapse (choices A and B are incorrect). Although radiation therapy may reduce the risk of recurrence, it has no role in acute management of pericardial effusion with tamponade physiology.
A 57-year-old woman with history of breast cancer treated with L. mastectomy and chemotherapy and radiation presents with a 1- week history of headaches, gait instability, progressive confusion, and a new onset seizure. On physical examination she is somnolent and only opens her eyes in response to voice. She is only oriented to person (knows her own name) but is not oriented to place or date. She does not follow commands but does withdraw from painful stimuli. Emergent noncontrast head CT is performed, which reveals multiple masses with surrounding edema and no evidence of blood.
Based on the data provided what is the patient’s Glasgow Coma Score?
Correct Answer: A
The Glasgow Coma Scale provides a practical method for assessment of impairment of conscious level in response to defined stimuli. The scale measures the mental status of patients according to three categories of responsiveness: eye opening, motor, and verbal responses table below.
Glasgow Coma Scale Score:
The patient in this scenario opens her eyes to voice (3 points), withdraws from painful stimulus (4 points), and is confused and disoriented (4 points) and therefore has a Glasgow Coma Score of 11.
What is the most appropriate intervention for this patient at this time?
Correct Answer: B
Brain metastases occur in up to 20% of the patients with cancer and indicate poor prognosis. Lung cancer, breast cancer, renal cell carcinoma, and melanoma are the most common types of cancer that metastasize to brain. Contrast-enhanced magnetic resonance imagining is the study of choice for diagnosing brain metastases.
IV glucocorticoids are indicated in symptomatic patients with brain metastases and surrounding edema and can be symptomatically effective within hours of administration.
The patient in the question is able to protect her airway, and therefore at this point there is no indication for endotracheal intubation (choice A is incorrect). Although radiation therapy may play a role in long-term management of brain metastases, there is no role for radiation therapy in acute management (choice C is incorrect). Although the patient does have evidence of increased intracranial pressure (headache, nausea/vomiting), conservative measures such as glucocorticoids should be attempted first. In comatose patients or those with severely increased intracranial pressure (TBI, obstructive hydrocephalus, intracranial hemorrhage), hyperventilation, hyperosmolar therapy with osmotic diuretics, and extra ventricular drainage of cerebrospinal fluid may be utilized to reduce intracranial pressure.
A 47-year-old man with recent diagnosis of pheochromocytoma is admitted to the ICU for management of hypertensive crisis. A radial arterial catheter is placed, and the patient is started on sodium nitroprusside with goal systolic blood pressure of 140 to 160 mm Hg. During rounds on the second day following ICU day, the bedside nurse notifies you that the patient’s blood pressure has been progressively increasing despite up titration of the nitroprusside infusion. On examination, the patient is complaining of headache and appears anxious and confused. His skin is flushed and he is tachycardic and hypertensive. The sodium nitroprusside is discontinued, oxygen administered, and a nicardipine infusion is started.
What is the most appropriate to administer for treatment of this patient?
Correct Answer: D
Sodium nitroprusside interacts with oxyhemoglobin and releases cyanide, methemoglobin, and nitric oxide. Prolonged infusions of sodium nitroprusside or doses exceeding 2 µg/kg/min increase the risk of cyanide toxicity as cyanide avidly binds ferric iron of cytochrome oxidase, inhibiting oxidative phosphorylation and leading to anaerobic metabolism and lactic acidosis. The patient in this scenario has developed tachyphylaxis to sodium nitroprusside, which is a sign of cyanide toxicity. Sodium nitroprusside should be promptly discontinued and therapy with sodium thiosulfate initiated.
Addition of a fenoldopam infusion to the nicardipine infusion may help to control the patient’s blood pressure but will not fix the underlying cyanide toxicity (choice D is wrong). Methylene blue is the therapeutic agent of choice for management of methemoglobinemia, which can develop in association with nitroprusside or nitroglycerine infusion. However, the patient in this scenario suffers from cyanide toxicity not methemoglobinemia (choice C is incorrect).
Silver nitrate is an inorganic chemical with antiseptic activity. It also is used as a cauterizing or sclerosing agent. It is not a treatment for cyanide poisoning (choice A is incorrect).