Air travel-related symptomatic deep venous thrombosis in cruise ship passengers

Abstract

Background: Long air travel is a risk factor for deep venous thrombosis (DVT). The aim of the study was to report the occurrence of symptomatic DVT cases in cruise ship passengers after long haul flights and to discuss applied diagnostic methods.

Materials and methods: A retrospective analysis of medical records of adult patients diagnosed with DVT in medical facility of the passenger ship was performed. On the basis of clinical examinations, B-mode ultrasound scans of the lower extremity venous systems, international normalised ratio (INR) tests, working diagnoses of DVT were established. The Wells score was used for stratification. Within 4–48 h of the diagnosis, D-dimer tests in blood, ultrasound Duplex examinations and specialists’ consultations of DVT suspected patients were performed ashore.

Results: A study showed 3 (0.15%) patients suspected of DVT of a total number of 2,007 passengers who have completed a flight > 8 h in the analysed period. The medial time from the embarkation to the onset of symptoms was 68.7 h. Based on the Wells DVT score, in 2 (0.1%) patients the probability of DVT was determined to be likely. Both the ultrasound examinations and D-dimer tests were positive. Those patients were diagnosed by shore specialists as DVT. One (0.05%) patient determined as DVT unlikely according to the Wells scale, her INR indicated hypercoagulable state, but Duplex scan as well D-dimer test were negative and DVT suspicion was excluded.

Conclusions: A clinical suspicion of DVT among passengers who joined the ship after their long haul flights could be an important diagnostic problem for ship’s doctors. The Wells scale allows to stratify the risk, but to rule out suspicion of DVT, a negative result of D-dimer test must be demonstrated. A portable ultrasound device helps in onboard clinical evaluation of DVT suspected patients. Due to possible fatal complications of DVT which can lead to pulmonary embolism and cause medico-legal issues, a definitive diagnosis should only be obtained in cooperation with land-based health care providers.