Effects of flying on patients with cardiovascular disease.

Abstract

The enormous increase in air travel during recent years has, among other results, led to the necessity of con sidering its effect upon passengers suffering frem organic disease. The physical standards insisted upon by Government services and by private air lines in the selection of pilots and air crews of all sorts are naturally very high. This attitude has perhaps led to the paral lel conclusion that none but physically fit individuals can safely be subjected, as passengers, to the strains and stresses of this form of transport. Whittingham, Barbour, and Macgown (1949) surveyed, from the point of view of air-fitness, most of the common medical diseases. They referred to cases of heart disease as follows: Those suffering from angina pectoris must have the condition adequately controlled with trinitrate, and an electrocardiogram should be done to exclude infarction: such cases can be accepted if the angina is provoked only by a brisk walk of half a mile. Cases with congenital heart lesion can be accepted for low altitude flights if there is no veno-arterial shunt as evidenced by cyanosis, or if there is no heart-block or severe hypertension resulting from coarctation of the aorta. Cases of high blood pressure are acceptable if the systolic pressure is not over 200 mm. Hg and the diastolic is less than 120, provided they have flown be fore and there is no pulsus alternans, cardiac asthma, gross albuminuria, or cellular casts in the urine: those who have not flown before may be upset by nervous tension. Whittingham (1953) states: Cardiovascular disease of marked degree is present in about three-quarters of those who are taken i1J during flight. The low oxygen tension, even at altitudes between 5,000 and 8,000 ft. (1,500 and 2,400 metres), throws a serious strain on the heart. These patients should travel in a pressurized aircraft and limit their movements to the minimum; oxygen and any special drugs prescribed by their doctors should be available; and the medical department of the air line should be made aware of their condition. Patients with angina or coronary occlusion should not fly unless they have been free from symptoms for at least three, preferably six, months. Even then the altitude should be limited to 5,000 ft. (1,500 metres). A test of fitness for anginal patients is whether they can walk briskly for about half a mile (0.8 km.) without symp toms. Patients with valvular disease should not fly while the condition is acute, nor when it is chronic if there are signs of congestive failure or pronounced 2naemia. Those with congenital heart disease can be accepted for flights up to 8,000 ft. (2,400 metres) altitude, in the absence of veno-arterial shunt, as evidenced by cyanosis, heart-block, or severe hypertension resulting from co arctation of the aorta. Those suffering from myocardial lesions are unacceptable if there is marked bradycardia or if they have had diphtheria within six months. Cases of high blood pressure can be accepted if there is no pulsus alternans, cardiac or renal asthma, frequent headache, much loss of weight, gross albuminuria, cellu lar casts in the urine, or optic fundus change. They should be given a sedative before flight to prevent ner vous tension worsening their condition, particularly if they have not flown before. Whittingham's paper is naturally written from the point of view of the Director of Medical Services, British Overseas Airways Corporation, and quite rightly is conservative in its approach to the subject. An air line is responsible for the delivery, safe and sound, of its passengers; and from the point of view of its liability it must take stringent measures concerning the safe transportation of individuals known to be suffering from cardiovascular disease. My own experience has for some time been that this view is ultra-conservative, especially regarding cases whose journey is really necessary. I was therefore led to collect a series of patients suffering from the more serious forms of cardiovascular disease who to my know ledge had safely flown considerable distances.