Med Pharm 501/801, Fall 2005 Objective: This case is designed as an exercise for you to apply your newly acquired knowledge of autonomic pharmacology. To prepare for this case, you should review the physiology of blood pressure regulation and the pathophysiology of shock. LEARNING OBJECTIVES
When you have completed this exercise, you should be able to:
Describe the determinants of hypotension.
Describe the mechanism of action and the cardiovascular effects of the drugs commonly used to treat hypotension.
Outline the general strategy for treating different forms of hypotension.
The patient is a 40 yo male (Mr. Pat Jones) brought to the emergency department (ED) of University Medical Center (UMC) by paramedics on a Saturday night at 7:05 after he was found “unconscious” by a friend. His friend stated that Mr. Jones lives alone and works at a daycare center. He said Mr. Jones occasionally uses an “inhaler” for mild asthma, but doesn’t know of any other medical problems, medications, or illicit drug use. Mr. Jones had been at work on Friday, but had complained Saturday afternoon of headache and fever. His medical records at UMC include only a previous ED visit six months ago for a sprained ankle. The history of mild asthma was noted, but no medication allergies were recorded.
On admission to the ED, Mr. Jones’s vital signs are BP 90/60, P 132 regular, T 38, and R 36. You estimate his weight to be 70 Kg. He is stuporous (localizes and opens eyes to pain, makes incomprehensible sounds). There is no evidence of trauma. There are petechial and purpuric lesions of the skin involving all areas but more prevalent on the thighs than elsewhere. The remainder of the physical examination is unremarkable. CT scan of the head is unremarkable and lumbar puncture shows cloudy cerebrospinal fluid. Gram stain of the fluid shows multiple neutrophils and gram negative diplococci. Routine laboratory studies including blood and urine cultures are done. Electrocardiogram is normal.