To overcome the complications due to the use of noncompliant large diameter conventional chest drain devices, a flexible small diameter chest drain device was designed and simulated based on computational fluid dynamics (CFD) techniques. It was clearly shown that the pressure drop and velocity increase of the most distal drainage holes, which are located near the suction end, are dominant over other drainage holes. A conventional chest drain device with circular side holes showed higher mass flow rate due to larger cross sectional area. It also showed less dependency on the side hole placement compared to open channel, closed cavity chest drain with rectangular side holes. When all holes are opened the conventional chest drain showed 6% increase in flow rate while the open channel, closed cavity drain device showed 47% increase in flow rate reflecting a better design performance. These results provide an insight into the CFD-based optimal design of chest drain devices for potential applications in clinical intraoperative procedures.