Hypertensive crisis resident survival guide

# Overview
Hypertensive crisis is a term used to describe an acute elevation in the blood pressure which may or may not be associated with end-organ damage.  Hypertensive crisis includes both hypertensive emergency and hypertensive urgency.  Noncompliance with antihypertensive medications is the most common cause of hypertensive crisis.

# Classification
Hypertensive crisis can be further classified as hypertensive urgency and hypertensive emergency based on either the absence or presence of acute end-organ damage.

## Hypertensive Urgency
Hypertensive urgency is an acute severe elevation in the blood pressure without any evidence of acute end-organ damage.

## Hypertensive Emergency
Hypertensive emergency mostly falls into stage 2 of hypertension (systolic blood pressure greater >160 mm Hg or diastolic blood pressure >100 mmHg).  It is usually an acute severe elevation in the blood pressure (systolic blood pressure  180 mm Hg, or diastolic blood pressure  120 mmHg) complicated by acute end-organ dysfunction, such as hypertensive encephalopathy, eclampsia, dissecting aortic aneurysm, acute left ventricular failure with pulmonary edema, acute myocardial infarction, acute renal failure, or symptomatic microangiopathic hemolytic anemia.

# Causes

## Life Threatening Causes
Hypertensive crisis is a life-threatening condition and must be treated as such irrespective of the cause.

## Common Causes
- Antihypertensive medications withdrawal ( beta blockers, clonidine)
- Noncompliance with antihypertensive medications
- Pheochromocytoma
- Side effects of monoamine oxidase inhibitors
- Stimulants (cocaine, methamphetamine, phencyclidine)
It can develop de novo or can complicate essential or secondary hypertension.

# FIRE: Focused Initial Rapid Evaluation
A Focused Initial Rapid Evaluation (FIRE) should be performed to identify patients in need of immediate intervention. 
Boxes in the red color signify that an urgent management is needed.

# Complete Diagnostic Approach
A complete diagnostic approach should be carried out after a focused initial rapid evaluation is conducted and following initiation of any urgent intervention.

# Treatment
Shown below is an algorithm summarizing the management of hypertensive crisis according to the seventh report of the joint national committee on prevention, detection, evaluation, and treatment of high blood pressure: the JNC 7 report.

## Initial Approach

## Intravenous Antihypertensive Drugs
Shown below is a table of the IV antihypertensive drugs and their appropriate doses.

## Oral Antihypertensive Drugs
Shown below is a table of the oral antihypertensive drugs and their appropriate doses.
- Other agents to consider include:
- PO frusemide 20mg (repeat as necessary)
- PO nifedipine SR 30mg, single dose
- PO felodipine 5 mg, single dose

## Management of Specific Hypertensive Emergencies

# Dos
- Hypertensive emergencies are best managed with a continuous infusion of short-acting titratable antihypertensive agents.
- Avoid sublingual and intramuscular routes of drug administration due to their unpredictable pharmacodynamics.
- Assess the patient' volume status before initiating intravenous vasodilators to prevent or minimize a substancial fall in blood pressure.

# Don'ts
- Don't consider nifedipine, nitroglycerin and hydralazine as first-line therapies in the management of hypertensive crises due to their potential toxicities and adverse effects.
- Don't use intramuscular or sublingual antihypertensive medications in the case of hypertensive emergency.
- Don't use rapid acting antihypertensive if the patient is not in  an ICU setting.