TSRA Content:
Author: Rachel Deitz, MD, MPH
A call or page about elevated blood pressure will be a common occurrence during day coverage or overnight call. Most pre-and post-operative patients will have vitals scheduled Q4 or Q8 hours and deviations from the norm should be addressed. In the text below we will outline some important concepts to consider along with common medications to treat.
Initial work-up should include:
Vital Sign Assessment:
- Consider all the vital signs in addition to the BP reading.
- Tachycardia and/or hypoxia accompanied by hypertension can provide key information about patient condition or underlying cause to the rise in blood pressure requiring additional management.
Physical Exam:
- Are there signs of hypertensive emergency?
- Is the patient sweating, in distress, or in acute pain?
History:
- A brief chart review with focus on past medical history and home medications
Next, consider the etiology of elevated blood pressure:
Untreated/undertreated essential hypertension
A very common reason for elevated BP is a patient with essential hypertension that is not on their home regimen. Certain antihypertensives may have been held prior to cardiac surgery (such as ACE inhibitors). Oral antihypertensives are likely held in the immediate perioperative period due to changes in hemodynamics and NPO status.
Pain
Sympathetic activation in the form of undertreated postop pain is another common etiology for elevated blood pressure. Evaluate the patient’s pain regimen and level of discomfort. Distinguish between opioid naïve and opioid tolerant patients and make sure that home pain regimens are started as early as possible.
Panic/Agitation
Feelings of panic or anxiety are not uncommon in post-surgical patients in the hospital setting and may contribute to acute hypertension. If appropriate, the root cause can be addressed and medications treating agitation can be helpful in certain cases.
Withdrawal
Hypertension may be one of the first noticed signs of acute tobacco or alcohol withdrawal. Alcohol withdrawal, potentially quite dangerous, may be treated with EtOH, benzodiazepine, or barbiturate taper. Hypertension is an important diagnostic hint that alcohol withdrawal is settling in, which may be an indication for closer monitoring (i.e. in the ICU setting) and for prompt treatment.
Other potential causes for high blood pressure:
- Respiratory Distress
- Acute MI
- Volume Overload
Consider the Context or Need for Treatment:
Evaluate cases in which relative hypertension may be important to maintain, or where it can be dangerous.
Reduce afterload in preop cardiac patients especially those with valvular disease or reduced ejection fraction. Remember that coronary perfusion is dependent upon diastolic blood pressure so too much afterload reduction can be harmful.
Patients with acute aortic dissection need careful blood pressure monitoring, which will occur initially in the ICU but after a few days may be transferred to the floor where PO and PRN medications may be needed.
Permissive hypertension should be considered in various post-operative scenarios, such as TEVAR patients (to allow for adequate spinal arterial perfusion pressure) esophagectomy patients (in which a fresh anastomosis needs adequate blood pressure to avoid ischemia) or those who may have suffered an ischemic stroke (requiring increased cerebral perfusion pressure) among other examples.
First Choices for Control:
Good to treat acutely if >170-180 mmHg systolic
Good choices for BP control in a patient who is NPO:
- Hydralazine 10mg IV Q4 (watch for tachycardia)
- Labetalol 10mg IV Q6 (patient should be on telemetry, do not give if h/o asthma)
- Metoprolol 5mg IV Q6 (patient should be on telemetry, do not give if h/o asthma)
- Clonidine 0.1mg/24hr transdermal patch Qweek – can titrate to 0.6mg (takes hours – days to work, watch for rebound)
Quick fixes in the middle of the night (each hospital has different rules for what you can push on the floor— hydralazine is your safest, most universal bet):
- If NPO: o Metoprolol 5mg IV x1 o Labetalol 10mg IV x1 o Hydralazine 10mg IV Q3 repeat x2
- If taking PO: o Labetalol 100mg PO x1 (takes hours to work) o Clonidine 0.1mg PO x1