Pulmonary thromboembolism after travel

Bs.J.

Dis. Chest (1977) 71, 138

Short Communication PULMONARY

THROMBOEMBOLISM TRAVEL

IAN S. SYMINGTON” Department

of Respiratory

Medicine,

AFTER

AND BRYAN H. R. STACK Western Infirmary Glasgow

and Knightswood

Hospital,

Summary Pulmonary thromboembolism developed in eight patients shortly after travel. Preexisting vein disease was present in this group. Possible prophylactic measures are suggested.

Venous stasis predisposes to intravascular deep vein thrombosis (Virchow 1856). It would be expected that travellers who sit for long periods in motor vehicles, trains or aircraft would be prone to develop deep venous thrombosis and its thromboembolic sequelae. There have been few reports, however, of this occurrence. Beighton and Richards (1968) describe one death from paradoxical embolism after air travel and Horsley et al. (1975) reported seven cases of deep venous thrombosis and pulmonary thromboembolism in a series of 186 medical emergencies among holidaymakers in Cornwall, many of whom had presumably travelled there by car. We wish to describe eight cases of pulmonary thromboembolism which occurred after travel.

PATIENTS

AND

RESULTS

During a three-year period 182 cases of pulmonary thromboembolism were diagnosed in the Glasgow Western Group of hospitals. Table I summarizes the main features of eight of this group who developed acute symptoms after a journey. There were five men and three women; most were middle-aged or elderly. The journeys occupied between three and 24 hours (average 10 hours) and were made by car (3), aircraft (3), rail alone (1) and rail/ship combined (1). The first symptoms were experienced between two and 96 hours after the end of the journey and all were of sudden onset. Two patients had evidence of bilateral pulmonary involvement and these individuals had a more serious initial illness, although all had recovered satisfactorily both clinically and radiologically after two months. All except two had a previous history of venous disorders in the legs and of this group three had clinical evidence of deep calf vein thrombosis and one of active superficial * Present Glasgow G2

adress 4PH.

: Employment

Medical

Advisory

Service,

Portcullis

House,

India

Street,

Sex

M

M

F

M

F

M

F

M

Patient

1

2

3

4

5

6

7

8

4 13

Car

6

Air

car

3

16

Air

96

72

36

2

96

48

48

14

of

Air

68

30

believed

Time between end of journey and onset symptoms (hours)

of patients

48

24

Duration of travel (hours)

features

5

Car

Rail/ship

Rail

84

Clinical

Mode of travel

I.

60

43

48

6.5

42

Age

Table

-

+

-

-I-

Previous venous disorder

to have

pulmonary

Normal

Chest Deep

pain venous

Normal

Minor left effusion

zone

basal

Right triangular opacity in right mid-zone

Chest pain Dyspnoea thrombosis

basal effusion Right lower lobe opacity

Left

Bilateral linear atelectasis

Chest radiograph

travel

Right lower opacity

after

Chest pain Dyspnoea

Chest pain Palpitation

thrombosis

thrombosis

presentation

Chest pain Haemoptysis Thrombo-phlebitis

Chest pain Dyspnoea Deep venous

Chest pain Dyspnoea Haemoptysis

Chest pain Dyspnoea Deep venous

Clinical

thromboembolism

-

-

Perfusion defect

-

defects

Perfusion defects

scan

Lung

2

3

tc

Y 2

P

ifig e k

140

Ian S. Symington and Bryan H. R. Stack

thrombophlebitis at the time of admission. Their previous general health was otherwise satisfactory and none of the women was taking oral contraceptives. The three air journeys were completed under normal cabin pressures on tourist-class scheduled services between Britain and India (2), and Portugal (1). The three car journeys were undertaken on holiday expeditions and those affected were all drivers. The ship/rail traveller volunteered that conditions in his train compartment were exceedingly cramped during his overnight journey on which he had to sleep for some hours in the sitting position. \

DISCUSSION

The term ‘economy class syndrome’ has been used to describe the venous problems caused by the cramped seating arrangements in modern aircraft, but it would appear that the syndrome is not restricted to that means of transportation alone. Venous stasis is the most important cause. Wright and Osborn (1952) have shown that the linear velocity of venous blood flow in the lower limbs in the recumbent position is reduced by half in the standing position and by two-thirds when sitting. It is likely that stasis is increased further by pressure of the edge of a seat on the back of the calves or by sitting for long periods with legs crossed. This is particularly likely to occur in those with previous venous disease and this is confirmed by our finding of this history in six out of eight patients. Another possible cause factor is haemoconcentration due to liquid loss. Carruthers et al. (1976) have demonstrated reduction in urine output during air travel with an increase in urine osmolarity. The resulting haemoconcentration may also be a significant factor in the formation of thrombus during transit and the need for an adequate liquid intake is apparent. Measures to prevent this complication of travel should include regular changing of position, preferably with occasional walking and at least some exercises at rest (Johnson 1973). Travellers should also be encouraged to drink plenty of liquid. REFERENCES BEIGEITON, 30, 367. CARRUTHERS,

P. H. & RICHARDS,

P. R. (1968) Cardiovascular

disease in air travellers

BY.

Heart

J,

M., ARGUELLES, A. E. & MOSOVICH, A. (1976) Man in transit: Biochemical and physiological changes during intercontinental flights. Lancet 1, 977. HORSLEY, S. D., SMAIL, P. J. & THOULD, A. K. (1975) Effects of influx of holidaymakers on an acute medical unit in Cornwall. Br. med. J. 4, 276. JOHNSON, H. D. (1973) Traveller’s ankle. Br. med. J. 4, 300. . VIRCHOW, R. (1856) Gesammelte Abhandlungen ZUY Wissenschaftlischen Medicine, p. 227. Frankfurt: Meidinger. WRIGHT, H. P. & OSBORN, S. B. (1952) Effect of posture on venous velocity. Br. Hearty. 14, 325.