WHITE COAT HYPERTENSION

 

RB “Doc” Hecker

 

FAA Senior AME 20969

 

EAA Flight Advisor 1905 / Technical Counselor 5453

 

 

 

 

Nothing seems to disrupt the persona of the smooth, sophisticated, highly trained and experienced aviator more than the FAR § 67 mandated visit to the FAA Aviation Medical Examiner (AME) to complete the ritual that typically leads to renewal of some form of Medical Certificate.  In fact, when considering the more training the pilot has received, the odds are greater that he or she will visit the AME more often for occupational reasons.  A very common scenario regarding the finding of elevated blood pressure readings observed by AMEs has been termed “White Coat Hypertension”, an almost automatic expression of occupational anxiety.  In essence, this syndrome is understood by the aeromedical community to be an exaggerated blood pressure response in an individual with known mild hypertension (elevated blood pressure) or unknown pre-hypertension when being evaluated by a physician.   The syndrome is worthy of continued observation by aeromedical physicians as its identification can alert the AME to look for potential problems associated with a later diagnosis of sustained hypertension and possible end organ damage.

 

The medical standards that apply to hypertension are defined in FAR § 67.113 (b)(c), § 67 213 (b)(c) and § 67.313(b)(c) for first, second and third class certificates respectively.  Currently, the FAA considers the measurement of blood pressure to be an essential part of the FAA medical certification examination.  The average blood pressure while siting should not exceed 155 mm mercury systolic and 95 mm mercury diastolic blood (155/95) maximum pressure for all medical certificate classes.   White coat hypertension (also termed “office” or “clinic” hypertension) is seen in about 20-40% of aviators with mild hypertension who present for routine aeromedical or other routine evaluations.  The diagnosis of this syndrome is typically made by the AME after observing elevated blood pressure readings in the office followed up by normal blood pressure readings over a 3-5 day period or by the airman documenting normal home blood pressure measurements.  Numerous studies have confirmed this phenomenon, and the exaggerated blood pressure effect is seen more often when the physician is evaluating the airman compared to the office nurse or technician.  The observation of white coat hypertension in an aviator without known history of hypertension is considered by some aeromedical examiners to be a condition of pre-hypertension.

 

The AME must consider two questions when confronted with white coat hypertension:    1):  How to best document this condition in an aviator, and 2):  Should it be considered a normal variant or indicate a pre-hypertensive condition?  The textbook answer to the first question is to either recheck the airman’s blood pressure in the office every 3-5 days, or to ask the airman to measure his or her blood pressure at home on an assigned schedule and to report a log.  The newer automated recording home use blood pressure devices are very useful to the AME in answering this question.  Secondly, the more important question centers on trying to decide whether the elevated blood pressure is a normal variant or an indicator of an abnormal process.  While most AMEs will try to dismiss the elevated blood pressure as a “normal” automatic response to occupational anxiety, it is good aeromedical practice to follow these airmen for signs of progressive pathology leading to a diagnosis of true hypertension or end organ damage that requires medical treatment.

 

“Optimal” resting blood pressure is assumed to have values in the range near or below 120/80; however, ambulatory pressures in the range of 120-133 systolic and 65-78 diastolic appeared to be quite favorable based upon mortality studies.  Although within current FAA limits of 155/95, any aviator with blood pressure readings greater than 140/90 in either number deserve a hypertensive evaluation and possible treatment to avoid end organ damage.  The FAA allows most pilots to fly with blood pressure medications after appropriate evaluation, treatment, and a 30 day stabilization period on medications or change in medications.

 

If your AME diagnoses white coat hypertension you will pass that portion of your aeromedical examination.  However, most AMEs will note this phenomenon and should most likely ask you to consider long-term logging of home blood pressures in order not to miss a diagnosis leading to true hypertension and its associated long-term organ damage.

 

Your AME is there to keep you flying!   

 

References:

 

US Department of Transportation, Federal Aviation Administration, Guide for Aviation Medical Examiners, 2012.

 

Rayman, RB et al:  Clinical Aviation Medicine, 4th Edition, Professional Publishing Group, New York, NY, 2006.

 

 

RB “Doc” Hecker (EAA 789419) is a FAA Senior AME (20969) who retired from the US Army Medical Department in 1997 after 26 years of service.  He holds a Commercial/Instrument Pilot Certificate for ASEL, AMEL and ASES along with an A&P Mechanic Certificate.  He has logged over 2,500 hours and prefers small, intimate airparks.  He has restored a 1965 Cessna C210E (N4904U), a 1946 Taylorcraft BC12-D (NC43306),a 1946 Aeronca 7AC (NC2241E), refurbished a 1943 Aeronca O-58B / L-3B (NC47185) and a 1947 Taylorcraft BC12-D (N43928).  He is currently restoring a 1947 Aeronca 7BCM / L-16 (N119TX).  His other projects include building a RV-8 (N51TX) and he is assisting in the restoration of a 1976 Taylorcraft F-19 (N3556T).  He has previously owned a Cessna C-172 (N61785), a Grumman AA-5B (N74447) and a Mooney M20C (N10AD).  In his free time, Doc practices medicine in San Antonio, TX.  He is a member of EAA Chapter 35 of San Antonio, TX, EAA Chapter 92 of Orange, CA, and is an EAA Technical Counselor and Flight Advisor.  In addition, he is a Life Member of the Commemorative Air Force and affiliates with the Tex Hill Wing (Hondo, TX), and crews with the Gulf Coast Wing (Houston, TX) as a Flight Engineer and member of the maintenance team where he does sheet metal and fabric repair work on that magnificent 1945 B17-G war bird “Texas Raiders” (N7227C).  

 

September 18, 2012