Objective      To study the coagulation of patients with lung cancer or esophagus cancer in thoracotomy during perioperative period.       Methods      Variables [reaction time (R)

clotting time (K)

α angle

maximu

m amplitude (MA)

]

detected by thrombelastography were measured in 10 cases of lung cancer and 10 cases of upper or median esophagus cancer before anesthesia (T

0

)

at the end of 1 h after operation beginning (T

1

) and 30 min after operation (T

2

). The control group consisted of 10 healthy volunteers.       Results      In lung cancer group and esophagus cancer group

R was shorter than control group (P0.05). R and K were longer

α angle and MA were smaller at T

1

than at T

0

(P0.05)

and MA was smaller at T

2

than at T

0

in lung cancer group. R and K were longer

α angle and MA were smaller at T

1

and α angle and MA were smaller at T

2

in lung cancer group than in esophagus group (P0.05). LY

30

(fibrinolysis index) at T

1

and T

2

was longer in lung cancer group than in esophagus cancer group (P0.05). CI （coagulation index） was longer at T

2

in esophagus cancer group than in lung cancer group (P0.05).        Conclusion      Patients with lung cancer or esophagus cancer have possibility of hypercoagulability before operation. Coagulability of  lung cancer patients decreased during and after operation

and hypercoagulability of esophagus cancer  patients continued during and after operation.