This document discusses recommendations for treating hypertensive employees who may be deployed to extreme temperature conditions. It is recommended that long-acting dihydropyridine calcium channel blockers, ACE inhibitors, or ARBs be used instead of diuretics, as diuretics can interfere with heat acclimatization. Low doses of thiazide diuretics may be used if necessary, but patients should be monitored for dehydration. The document also outlines conditions like heart disease that may result in disqualification from deployment.

1. Extreme Temperature
Pre –employment criteria---
Hypertensive Person
By—Dr.Ashok Laddha
Full Presentation Under
Process

2. BACKGROUND
 There are special situations related to deployment and readiness when
it comes to control of HTN and since conditions and physiologic
responses may be quite different in extreme deployment conditions,
the general recommendations for drug therapy need to be modified.
Many drugs including diuretics and beta blockers might have negative
effects on the heat acclimatization process. It is critical for readiness
that employees are able to acclimate quickly and safely when they
arrive , treatment with an anti-hypertensive agent, especially a diuretic,
may interfere with some changes such as increasing total body water
and plasma volume. This might prolong the process of heat
acclimatization. It may also make the increased sweating and altered
electrolyte loss associated with heat acclimatization more dangerous.
The physiologic changes induced by heat acclimatization may also
make certain anti-hypertensive agents, such as diuretics, less effective
since they work counter the effect(s) of the drug.

3. Heat--acclimatization
 The human body’s response to heat stress is quite
resilient if given several weeks for adaptation to occur.
This process, called acclimatization, involves internal
adjustments, in response to the outside environment
 which improve heat tolerance. This adaptation can be
fully achieved after 10 to 14 days of exposure to heat,
but two-thirds, or even 75 percent, of the adaptation
takes place within five days.

4. Heat—acclimatization---2
 subsequent to repeated bouts of exercise in a hot
environment, there is a marked improvement in the
physiologic responses of healthy humans. This improved
tolerance to exercise in heat is known as heat
acclimatization. When accomplished in an artificially
controlled environmental chamber, this process is known
as heat acclimation.
 The primary benefit of heat acclimatization is improved
tolerance of exercise in the heat, evident as a reduction of
the incidence or severity of symptoms of heat illness, and
increased work output concurrent with reduced
cardiovascular, thermal, and metabolic strain.

5. Heat Illness
 Heat Cramp
 Heat syncope
 Heat exhaustion
 Heat stroke
 The aforementioned heat illnesses all involve either fluid-
electrolyte balance, extracellular volume and tonicity, or
cardiovascular adaptation. This emphasizes the importance of
(a) ample dietary intake of NaCl and fluids, and (b) fluid-
electrolyte hormone regulation during heat acclimatization.

6. Definition
 When boy is unable is unable to cool itself through
sweating serious heat illnesses may occur. the most
serious heat induced illnesses occurs are heat
exhaustion and heat stroke. If left untreated heat
exhaustion could progress to heat stroke and possibly
death
 High TEMPRATRURE +High HUMIDITY +Physical
work=Heat Illness

7. RECOMMENDATIONS
 The following recommendations to be followed, based on
consensus opinion that considers the available literature,
experience in the field, and physiology---
 1. Clinicians should discuss how deployment might affect blood
pressure control and describe potential complications of
treatment with their patients .
 2. For active duty employees who might be going into above
condition that increase the risk of dehydration, long-acting
dihydropyridine CCBs (LADHP) or ACEI/ARBs would be the
preferred agents, rather than a diuretic.
 3Thiazide diuretics if used, low doses are recommended. And
the patient should be monitored for s/s of dehydration and
adequate blood pressure control for the first 7-10 days of
deployment while they are becoming acclimatized.


8. RECOMMENDATIONS-2
 4. For active duty employees, who are diagnosed with
hypertension during a deployment in above condition
that increases the risk of dehydration, LADHPs would
be preferred These agents are to be given once a day,
do not limit heart rate, and do not require electrolytes
to be checked after initiation
 5. Health education on heat acclimatization
 6. Safety measures as well as preventive measures.
 Final decision lies with occupational health
physician.

9. Treatment Modality:
 Preferred Agents for Patients in High Ambient
Temperatures or in Other Extreme Conditions that
Increase Dehydration Risk
 Preferred agents
 LADHP
 ACEI
 ARB
 Alternate agents
 CCB
 Low dose
 Thiazide-type diuretic

10. CONDITIONS WHICH MAY RESULT IN
DISQUALIFICATION
 PACEMAKERS or PROSTHETIC VALVES may be
disqualifying. Documentation from the individual’s
cardiologist, stating that the individual is stable and
can safely carry out the specified requirements of the
function, under the specified conditions, will be
necessary before a clearance can be granted.
 CORONARY ARTERY DISEASE A negative
exercise stress test, or documentation from the
individual’s cardiologist acknowledging the
requirements of the function and the work conditions,
may allow a clearance despite this diagnosis.

11. CONDITIONS WHICH MAY RESULT IN DISQUALIFICATION---2
 HYPERTENSION that cannot be controlled to a level
of 140/90 or less, or requires the use of any medication
that affects the ability of the individual to safely and
effectively carry out the requirements of the function,
may be disqualifying.
 LEFT BUNDLE BRANCH BLOCK.
 MYOCARDITIS/ ENDOCARDITIS/ PERICARDITIS
(Active or recently resolved cases).

12. CONDITIONS WHICH MAY RESULT IN DISQUALIFICATION---3
 History of MI. Documentation from the individual’s cardiologist,
stating that the individual is stable and can safely carry out the
specified requirements of the function, under the specified conditions,
will be necessary before a clearance can be considered.
 Valvular heart disease such as mitral valve stenosis, symptomatic
mitral valve regurgitation, aortic stenosis etc. Exceptions may be
granted depending upon the current clinical findings and diagnostic
studies.
 Dysarythmias: Wolff-Parkinson-White syndrome, and Paroxysmal
Atrial Tachycardia, with or without block.
 ANGINA PECTORIS or chest pain of unknown etiology.
 Cardiomyopathy from any cause.
 CCF
 GRADE 4 Hypertension

13. Investigations
 The applicant/incumbent must have a cardiovascular system
that is sufficient for the individual to safely and efficiently carry
out the requirements of the job. This may be demonstrated by:
 A physical exam of the cardiovascular system that is within the
range of normal variation, including:
 blood pressure of less than or equal to 140 mmHg systolic and 90
mmHg diastolic; and
 a normal baseline electrocardiogram (minor, asymptomatic
arrhythmias may be acceptable); and
 no pitting edema in the lower extremities, and
 normal cardiac exam.
 No evidence by physical examination and medical history of
cardiovascular conditions likely to present a safety risk or to worsen as a
result of carrying out the essential functions of the job .