Diagnosis of Deep Vein Thrombosis (DVT) In Critically Ill Patients

The assessment of existences of DVT is important to prevent pulmonary embolism for hospitalized patients. Especially, there is a high incidence of DVT in critically ill patients in the intensive care unit (ICU). Because almost all the patients in the ICU have limitations of their activities of daily living due to unstable vital status, controlled under the analgesia, or multiple injuries. The aim of the present study is to evaluate D-dimer levels as a diagnostic marker of DVT in critically ill patients.

One-hundred ten adult patients (66 men, 44 women; age range 20–94 [median 64.5]) who admitted in our medico-surgical ICU in a university hospital were enrolled in this study. Serum D-dimer test and ultrasonic duplex scanning (ALOKA, Co., Ltd, Tokyo) were performed within one week after admission to the ICU. Serum D-dimer levels (μ g/mL) were measured by latex agglutination test (Sekisui Medical®, Tokyo) (normal <1.0μ g/mL). PT-INR (Quick one method) and APTT ratio (Langdell method) were also measured (Sysmex®, Kobe, Japan). DVT was diagnosed by ultrasonic duplex scanning. Value was expressed by median. Data were analyzed by Fisher's exact probability test and Mann-Whitney U test. A p < .05 was considered as statistically significant.

There were 32 patients (29.0 %) with DVT and 78 without DVT (71%) in the ICU. Primary diagnoses on admission were 31 cerebrovascular disease, 30 trauma patients, 16 sepsis, 9 acute respiratory failure, 8 hemorrhagic shock, 8 cardiogenic failure and 8 others. Between patients with DVT and without DVT, there were no significant differences in age (67.5 vs. 64.0, p=0.71), sex (19 men and 13 women vs. 47 men and 31 women, p=0.93), primary diagnosis (p=0.13), PT-INR (1.06 vs. 1.07, p=0.97) or APTT ratio (1.02 vs. 1.04, p=0.81), respectively. D-dimer level was also no statistically significant difference (10.4 vs. 7.3μ g/mL, p=0.21) between patients with DVT and without DVT. D-dimer level was higher in all DVT patients with DVT and in 95 per cent of non-DVT patients than normal range. Moreover, thromobosis tended to exist in soleal vein and femoral vein (Table)

The present study suggests that D-dimer level could not be a useful marker for assessment of existence of DVT in critically ill patients. And DVT almost existed in soleal and femoral veins. D-dimer level elevates because of the primary disease and/or complications of patients in the ICU. The ultrasonic duplex scanning is an easy and non-invasive examination at the bed side, while there is a limitation to perform it for ICU patients due to their unstable vital status, difficulty of appropriate posture, such as prone positioning, or injured lower limbs. But at least the examination by duplex scan of soleal and femoral veins, which have more possibility to develop to pulmonary embolism, could be significance in the ICU patients.

No relevant conflicts of interest to declare.