Improvement of the salvage-rate of flap after venous thrombosis with intraparenchymatous venous pressure monitoring
Intraparenchymatous venous pressure (IVP) monitoring in flap can measure venous pressure with catheter placement. Among patients with IVP monitoring, this study reviewed postoperative microvascular complications for investigating the transplanted-tissue salvage-rate.Patients and Methods
Two hundred and seventy-one patients (male, 132; female, 139; mean age, 52.3 years; age range, 9–82 years) underwent free flap transfer and postoperative continuous IVP monitoring, which performed as follows; a venous catheter was connected to a transducer, and venous pressure in the flap was recorded for three consecutive days postoperatively. The threshold of alarm for elevated venous pressure was set at 50 mm Hg. When abnormal measurements or fluctuation were observed, the vascular anastomotic site was exposed immediately. The flap salvage-rate of non-IVP monitoring group (n = 393; male, 305; female, 81; mean age, 61.3 years; age range, 23–83 years), which were confirmed by a portable ultrasonographic device, was compared with that of IVP-monitoring group.Results
Twenty-one patients developed postoperative microvascular complications at the vascular anastomosis sites. Sensitivity rate of IVP monitoring was 86%; specificity rate, 96%; positive predictive value rates, 64%; negative predictive value rate, 99%; false positive rate, 4%. The flap salvage-rate was 83% in venous thrombosis cases and only 33% in arterial thrombosis cases. In non-IVP monitoring group, flap salvage-rate was 20% with arterial thrombosis and 36% with venous thrombosis, resulting in an increasing the salvage-rate (P = .021).Conclusions
IVP monitoring could visualize and quantify venous pressure waves in flap and detect early microvascular complications, resulting in a marked improvement in the graft-tissue salvage-rate.