Transcript Duration of Action

Management of hypertensive
urgencies & emergencies
Emergencies:
BP> 180/120 – impending/ progressive target organ damage
- Immediate reductions required.
Urgencies:
severe elevations in BP without progressive target organ
damage
- Severe headache, shortness of breath, epistaxis, severe
anxiety
Emergencies:- decrease mean BP by 25%(within
minutes to one hour)
- If stable  to 160/100-110mmHg – next 2 – 6 hrs.
- Excessive fall!!!
-If stable – normal BP – 24 – 48 hrs
EXCEPTIONS: Patients with ischemic stroke
- Aortic dissection (↓SBP to <100 mmHg)
- Patients in whom BP is lowered to enable use of
thrombolytic agents
Oral agents: captopril, labetalol, clonidine
Complications of aggressive
management!
Treatment of acute severe hypertension in preeclampsia
Hydralazine ■ 5 mg iv bolus, then 10 mg every 20–30 minutes
to a maximum of 25 mg, repeat in several hours as necessary
Labetalol (second-line) ■ 20 mg iv bolus, then 40 mg 10
minutes later, 80 mg every 10 minutes for two additional doses
to a maximum of 220 mg
Sodium nitroprusside (rarely, when others fail) ■ 0.25
μg/kg/min to a maximum of 5 μg/kg/min
■ Fetal cyanide poisoning may occur if used for more than
4 hours
Treatment of acute severe hypertension in preeclampsia
Nifedipine (controversial) ■ 10 mg po, repeat every 20
minutes to a maximum of 30 mg
■ Caution when using nifedipine with magnesium sulfate, can
see precipitous blood pressure drop
■ Short-acting nifedipine is not approved by the Food and Drug
Administration for managing hypertension
Drug
Sodium nitroprusside
Dose
0.25–10 μg/kg/min as IV infusion
Onset of Action
Immediate
Duration of Action
1–2 min
Adverse Effects: Nausea, vomiting, muscle twitching,
sweating, thiocynate and cyanide intoxication
Special Indications: Most hypertensive emergencies;
caution with high intracranial pressure or azotemia
Drug:
Nicardipine hydrochloride
Dose:
5–15 mg/h IV
Onset of Action:
5–10 min
Duration of Action: 15-30 min, may exceed 4 hrs
Adverse Effects:
local phlebitis
Tachycardia, headache, flushing,
Special Indications: Most hypertensive emergencies
except acute heart failure; caution with coronary ischemia
Drug: Fenoldopam mesylate
Dose: 0.1–0.3 μg/kg per min IV infusion
Onset of Action: <5 min
Duration of Action: 30 min
Adverse Effects:
Tachycardia, headache, nausea, flushing
Special Indications: Most hypertensive emergencies; caution
with glaucoma
Drug:
Nitroglycerin
Dose:
5–100 μg/min as IV infusion
Onset of Action:
2–5 min
Duration of Action: 5–10 min
Adverse Effects: Headache, vomiting,
methemoglobinemia, tolerance with prolonged use
Special Indications: Coronary ischemia
Drug:
Enalaprilat
Dose:
1.25–5 mg every 6 hrs IV
Onset of Action:
15–30 min
Duration of Action: 6–12 hrs
Adverse Effects: Precipitous fall in pressure in highrenin states; variable response
Special Indications: Acute left ventricular failure; avoid
in acute myocardial infarction
Drug: Hydralazine hydrochloride
Dose: 10–20 mg IV 10–40 mg IM
Onset of Action: 10–20 min IV 20–30 min IM
Duration of Action:1–4 hrs IV 4–6 hrs IM
Adverse Effects: Tachycardia, flushing, headache,
vomiting,aggravation of angina
Special Indications: Eclampsia
Drug: Labetalol hydrochloride
Dose: 20–80 mg IV bolus every 10 min 0.5–2.0 mg/min IV
infusion
Onset of Action: 5–10 min
Duration of Action: 3–6 hrs
Adverse Effects: Vomiting, scalp tingling,
bronchoconstriction, dizziness, nausea, heart block,
orthostatic hypotension
Special Indications: Most hypertensive emergencies except
acute heart failure
Drug: Esmolol hydrochloride
Dose: 250–500 μg/kg/min IV bolus, then 50– 100 μg/kg/min
by infusion; may repeat bolus after 5 min or increase infusion
to300 μg/min
Onset of Action: 1–2 min
Duration of Action: 10–30 min
Adverse Effects: Hypotension, nausea, asthma, first degree
heart block, heart failure
Special Indications: Aortic dissection, perioperative
Drug: Phentolamine
Dose: 5–15 mg IV bolus
Onset of Action: 1–2 min
Duration of Action: 10–30 min
Adverse Effects: Tachycardia, flushing, headache
Special Indications: Catecholamine excess