Factors influencing response to lymphonodovenous shunt in filarial lymphoedema.

BACKGROUND

Although several studies have been published on lymphonodovenous shunt, there are no objective data either on the outcome of lymphoedema or on various parameters likely to influence the results.

METHODS

A trial of lymphonodovenous shunt was carried out in 75 patients with unilateral filarial lymphoedema. The primary aim of the trial was to identify a cohort of responders as against non-responders and to correlate the outcome with various factors such as age, gender, duration and preoperative grade of lymphoedema, number of preoperative attacks of adenolymphangitis, operative impression of the lymph node, effect of venous reflex and type of nodovenous anastomoses. Change in oedema volume was measured objectively by water displacement method using the normal limb as a control.

RESULTS

There was no operative mortality. Predominant postoperative complications included wound haematoma (8.5%), wound infection (13.6%) and transient lymphorrhoea (13.6%). In the immediate postoperative period, a reduction of 25%-50% in the oedema volume was recorded in 46.7% of cases and of more than 50% in 17.3% cases. The difference in response with respect to the type of lymphonodovenous shunt was not statistically significant, although the end-to-side type of shunt showed marginally better results. The response was significantly higher in patients with preoperative oedema volume more than 2 L. There was a significant reduction in postoperative attacks of adenolymphangitis, irrespective of the reduction in oedema volume. Of the 75 patients, 22 showed regression of oedema volume to preoperative or higher levels in the postoperative phase. A majority (21/22) could be identified as non-responders within 3 months of surgery.

CONCLUSION

The best results of lymphonodovenous shunt were seen in patients with large-volume lymphoedema. The results are better when combined with early excisional surgery. Other factors did not significantly affect the outcome. Non-responders could be identified within 3 months after surgery. Even in patients who did not respond well, a significant decrease in the frequency of adenolymphangitis attacks was observed. Higher initial oedema volume and history of higher frequency (25-50 per year) of adenolymphangitis attacks can be considered as indicators for good response to lymphonodovenous shunt.