By David Jaslow
One of the goals of the rehab sector is to identify individuals who are at greater risk of cardiovascular and cerebrovascular emergency before that event happens. Emergency responders are primarily men and many in this country develop hypertension before they are 40. Aside from heart rate, the other critical "traditional" vital sign that must be measured in the rehab sector is blood pressure. There are two primary reasons to measure BP: 1) detection of those emergency responders who have pre-existing hypertension and who have developed what is commonly known as hypertensive urgency; 2) discover those emergency responders who have essential hypertension (or some other cause for high blood pressure) who are unaware that they have this condition.
The National Heart, Lung and Blood Institute defines Stage I hypertension as a systolic BP of 140-159 and a diastolic blood pressure of 90-99. Stage II hypertension is defined as a systolic BP greater than 160 and a diastolic BP greater than 100. Both categories assume that BP measurements are taken properly and in patients who are not on any antihypertensive medications.
Hypertensive urgency is defined as severe elevation of blood pressure without evidence of target organ dysfunction (damage to heart, brain, kidney, etc.) This is the typical situation when paramedics or emergency physicians see a patient with a BP of 180/120 who does not appear to have symptoms and say to themselves, "Wow! That's high. That patient needs medication."
Interestingly, there is no exact "panic value" for blood pressure at which emergency medical treatment (in terms of immediate blood pressure lowering) is mandatory, although there are ranges that most physicians act upon. Generally speaking, no patient with a new onset systolic BP greater than 180 or a diastolic BP greater than 120 will be sent out of an ED without either confirming that he/she can be seen by their primary physician within 48 hours or the patient is started on medication prior to discharge.
Similarly, there is no "panic value" for low blood pressure, although most texts define hypotension as a systolic BP < 90 or a diastolic BP < 60. EMS personnel and Rehab Officers should bear in mind that healthy females, especially those who are of short stature and low body weight, typically have normal blood pressures that run less than 100 systolic. Any responder thought to be truly hypotensive becomes a patient and should be transported to an ED for evaluation and treatment.
The difficult questions to answer are, "Who requires transport to an ED just because their BP is elevated? Is there a simple protocol that can be designed to instruct EMS personnel what actions to take based upon abnormal BP readings?" The answer to both questions is that there is no EMS literature yet looking at outcomes of firefighters with elevated BP in the rehab sector nor is there much literature on any aspect of the firefighter rehabilitation process. It is not even clear whether emergency responders whose blood pressure does not return to a normal range after sufficient rest and rehydration definitely have pre-existing hypertension (although I operate under this principle because it is conservative and in the best interest of the responders to have follow-up whenever the possibility of new onset hypertension exists).
Another factor which complicates the evaluation of emergency responders' blood pressure in the rehab sector is that personnel may be taking anti-hypertensive medications but may still be hypertensive for a variety of reasons: Perhaps they missed a dose of medication; They may be inadequately controlled on the current dose of their medication or require additional drugs. Current recommendations are that most people will require two medications to achieve good blood pressure control. Departments that do not mandate annual fitness for duty exams or follow NFPA 1582 requirements are more likely to find that their personnel are hypertensive in the rehab sector.
I use the following algorithm to drive decision-making about how to handle hypertension in the rehab sector. What is most important to recognize is that blood pressure (as well as the other vital signs) should not be taken immediately as firefighters who have just performed heavy manual labor enter the rehab sector because their values will all be abnormal. All this reflects is the adrenaline surge and physical exertion that has just occurred. The issue is not who is hypertensive coming into rehab, it is who is hypertensive when he/she is otherwise ready to exit rehab. It is this group, in whom heat stress has been attenuated, that is most likely hypertensive at baseline or acutely ill from some other cause, even if they have no symptoms. Anybody who is hypertensive and has symptoms of acute illness becomes a patient and should be transported to an ED.
- BP < 140 systolic and < 90 diastolic meet criteria for discharge
- BP 140-160 systolic and 90-100 diastolic are discharged but told to follow-up with their physician for repeat BP measurement
- BP > 160 but < 180 systolic and BP > 100 but < 120 diastolic are placed on light duty and removed from active operations on the fireground. They must bring a fitness for duty note from their primary physician stating that BP has been addressed prior to returning to duty
- BP > 180 systolic or > 120 diastolic requires transport to the ED for evaluation
The bottom line concerning hypertension in the rehab sector is that there are no clear cut guidelines available for how to handle returning firefighters to the manpower pool versus taking them out of active duty purely for asymptomatic elevations in blood pressure. I urge you to think about the consequences of potential hypertensive crisis that may develop in someone who is found to have hypertensive urgency in rehab that is not acted upon. We should all practice preventive medicine!