Improved venous return by elliptical, sequential and seamless air-cell compression.

AIM: The risk of deep vein thrombosis (DVT) in the peri-operative period is significant, but can be reduced with the use of mechanical intermittent pneumatic compression (IPC). These devices have reached widespread use in hospitals and have been found to be effective prophylactic measures against DVT. This study evaluates the latest design features of one particular IPC device in comparison to current models. METHODS: Duplex ultrasound scanning was performed on 40 lower extremities of 20 healthy volunteers before and during the application of the IPC device (VenaFlow System, Aircas, NJ, USA. Two hemodynamic parameters were measured, acceleration time from spontaneous baseline venous flow and peak vein velocity. All measurements were obtained by scanning proximal to the saphenofemoral junction in the common femoral vein in both extremities for each subject. Data were obtained from 3 compression cycles and averaged for each extremity. Results were compared with a recent prospective study form our center using a slow-filling and a rapid-filling sequential IPC devices. RESULTS: The medians for spontaneous average peak velocities at rest of the right and left lower extremities were 26 cm/s and 24.1 cm/s. The median augmented peak velocities during the compression cycle of the device in the right and left side were 79.6 cm/s and 79.0 cm/s. This represented a 306.2% increase in average peak velocity on the right side and a 327.8% increase on the left side. The median acceleration time was 305 ms +/- 40 in the left and 310 ms +/- 50 in the right limb. There was no statistically significant difference in the spontaneous and augmented velocities between the right and left lower extremities in each subject. In comparison to existing slow- and rapid-filling IPC devices the VenaFlow System had superior peak velocities and shorter acceleration times. CONCLUSION: The use of elliptical, sequential and rapid-filling compression of the leg with overlapping air-cells produces significant hemodynamic changes in the common femoral vein, which are superior to other sequential slow- or rapid-filling IPC devices. Randomized studies should be performed to determine the efficacy of this new device in DVT prevention.

Age is not a contraindication to pancreaticoduodenectomy.

The incidence of pancreatic cancer has increased threefold over the last 40 years with the greatest rate of growth occurring in the elderly. In the past it was suggested that elderly patients tolerated pancreaticoduodenectomy less well than younger patients with higher mortality rates. This single-institution experience examines the question of whether age is a significant factor in relation to morbidity and mortality in patients undergoing pancreaticoduodenectomy. Between 1994 and 1999 outcomes of 122 patients who underwent pancreaticoduodenectomy were reviewed. There were 48 patients 70 years of age and older and 74 patients less than 70 years of age. Both groups were compared with respect to preoperative clinical prognostic determinates and perioperative factors affecting morbidity and mortality. There was no significant difference between the two groups comparing their comorbidities, use of preoperative antibiotics, intraoperative blood loss, or length of hospital stay (11.9 and 10.8 days respectively). The two groups were also similar with regard to pathologic diagnosis with pancreatic adenocarcinoma being the most frequently encountered neoplasm. There was one death in the less-than-70-year-old group and none in the older group. No significant difference in the rate of complications was appreciated. These data demonstrate that pancreaticoduodenectomy can be performed safely in patients 70 years of age and older with morbidity and mortality rates similar to those of younger individuals.

Current concepts in chronic venous ulceration.

OBJECTIVES: despite numerous reports on the distribution of reflux in patients with venous ulceration, there is no consensus on the contribution of each venous system. This study was performed to evaluate the distribution of reflux in this group of patients. METHODS: a literature search from 1980 to 1998 was performed. Because duplex scanning is the best method for detecting venous reflux, we only included reports that used this diagnostic modality. All studies with less than 30 ulcerated limbs were excluded. Since most reports did not give detailed data on perforator veins, reflux in these veins was combined with the superficial and deep veins. Documented episodes of superficial or deep vein thrombosis were noted. RESULTS: thirteen studies that included 1249 ulcerated limbs fulfilled the inclusion criteria. The mean age of patients was 59 years (95% CI: 54-63, range: 14-93). Reflux was detected in 1153 (92%) of limbs. Reflux confined to the superficial veins alone was seen in 45% of limbs, in the deep veins alone in 12% and in both the superficial and deep veins in 43% of limbs. The overall involvement of the superficial veins was 88% and of the deep veins 56% (p <0. 0001). A documented episode of deep vein thrombosis was reported in only six of the 13 studies and the incidence was found to be 32%. CONCLUSIONS: reflux in the superficial veins is seen in 88% of limbs with venous ulcers (CEAP classes 5 and 6). Isolated superficial vein incompetence is detected in 45%, while reflux in the deep venous system alone is seen in only 12%. These data have significant clinical implications, since reflux in the superficial system can be easily eliminated by excision of the affected veins.