Physician Assistant Exam: Hypertensive Urgencies and Emergencies
On the PANCE, expect to see common clinical scenarios involving very high blood pressure. Be aware of two basic scenarios concerning high blood pressure: hypertensive urgencies and hypertensive emergencies.
Hypertensive urgency concerns someone who presents with really high blood pressure: a systolic blood pressure >= 180 mmHg or a diastolic blood pressure >= 110 mmHg. The affected person is relatively asymptomatic and has no signs of end-organ damage on exam — no dizziness, no chest pain, no blurry vision, no nothing. He or she doesn’t usually require inpatient hospitalization but does require aggressive blood pressure management and follow-up.
Hypertensive emergency concerns someone who presents with blood pressure readings >= 180 mmHg systolic or >= 120 mmHg diastolic with symptoms and signs of end-organ damage. He or she may have a change in mental status, chest pain, kidney failure, or pulmonary edema, possibly in combination. The affected person can have damaged organs, and that may not be reversible, depending on the intensity of the initial symptoms.
A person in hypertensive emergency needs to be hospitalized, usually in an intensive care unit, with gradual blood-pressure lowering over the first 24 to 48 hours. Cerebral perfusion, especially cerebral autoregulation of blood pressure, can get all messed up when the systolic blood pressure is too high.
The general rule of thumb is to lower the blood pressure by no more than 20 percent of the mean arterial pressure (MAP) daily for the first couple of days. In other words, lower the blood pressure very slowly when you’re treating a hypertensive emergency.
Be aware of commonly used medications to treat hypertensive emergency and their precautions and side effects. Many times, a continuous intravenous infusion is needed to tightly regulate the blood pressure. A healthcare provider often begins with one medication and adds another if needed to help bring the blood pressure under control. Consider the following meds:
Nitroprusside (Nipride) is a potent vasodilator. A person on this medication needs to be in the ICU and should have an arterial line placed (usually in the radial artery) to measure blood pressure changes minute by minute. Side effects include cyanide toxicity, so thiocyanate and cyanide levels need to be monitored. Also, be careful giving this med to people with kidney disease or who are on dialysis.
Labetalol (Trandate) can be given as a continuous infusion. Rich likes using this first-line. Remember that this medication is both an alpha blocker and a beta blocker. It can bring down the blood pressure nicely.
Nicardipine (Cardene) is an intravenous calcium channel blocker. It also lowers blood pressure nicely.