Effects of pneumatic compression therapy on secondary lymphedema in a rodent model

Peripheral lymphedema is a common long-term disabling complication of successfully managed breast and pelvic cancer. Using a refined standardized rodent model of lymphedema induced by combined radical lymphatic/nodal excision and regional irradiation of the groin, we produced sustained unilateral hindlimb lymphedema in seven Wistar-Fuzzy rats. At 30 days when lymphedema volume was stable, rats were anesthetized and subjected to pulsatile pneumatic compression therapy (PC) delivered with a computer driven pump connected across a parallel network of two neonatal blood pressure cuffs for each limb. 30mmHg was applied across the network to both the lymphedematous (L) and contralateral control (C) hindlimb 6 hours daily for 5 days, Before and immediately after each 6 hr treatment, circumferential measurements were made at standardized intervals along the limb and limb volume (truncated cone formula) as well as percentage change in limb volume determined after each 6 hr PC treatment and at the end of the 5 day PC treatment sequence. Results: L volumes were 148±15.4% (mean±SEM) of C volumes at the beginning of PC. The effect of PC on pre-treatment limb volumes (% change) is shown in the Table. 6 hr PC 5 day PC L C L C -14.2±1.7* -6.7±1.8 -24.6±5.7* -0.5±4.3 * p<0.01 L compared with C Pneumatic compression pumping substantially reduced lymphedema limb volume acutely during single 6 hr daily treatments and led to a steady continued decline in lymphedema volume over the five day treatment period. The findings suggest that this experimental counterpart of the human condition can be used to standardize, test, and compare mechanisms and efficacy of treatment modalities to reduce lymphedema.