Excessive use of diathermy could lead to increased haemorrhage rates

The postoperative haemorrhage rate in tonsillectomies which use ‘hot techniques’ such as diathermy and coblation to stop bleeding could be over three times greater than operations which use cold steel techniques, conclude authors of a study in this week’s issue of THE LANCET.

Tonsillectomy is one of the most common surgical procedures. “Hot” techniques such as diathermy (the use of an electric current at 400–600°C to remove tonsils and to control bleeding) and coblation (a variation on electrosurgery, which operates at 60–70°C, reducing the chance of thermal damage) have become well established alongside the traditional “cold” dissection techniques, which only use packs or ties to minimise intraoperative bleeding. Until now, there is little evidence to say one technique is better than the other.

The National Postoperative Tonsillectomy Audit (NPTA), launched in July 2003 and funded and supported by the UK Department of Health, is investigating haemorrhage and other postoperative complications from all tonsillectomies done in 334 hospitals in England and Northern Ireland. The audit is running in both the NHS and private-sector hospitals. Data from around 12,000 patients were obtained from operations using a combination of hot and cold techniques and from operations that only used cold techniques.

Haemorrhage occurred in 3•3% of patients within 28 days of surgery. Analysis showed that any use of diathermy increased the rate of haemorrhage, in some cases by as much as 6% compared with the ‘cold steel only’ technique. Adults had higher haemorrhage rates than children, and haemorrhage was more likely from procedures done by junior surgeons.

The investigators suggest that diathermy should be used with caution and that when junior surgeons are trained it should be emphasised that control of intraoperative bleeding with excessive use of diathermy could lead to increased haemorrhage rates. One of the authors, Jan van der Meulen (London School of Hygiene and Tropical Medicine / Royal College of Surgeons of England), comments: “Although our findings favour cold steel without diathermy, we do not think that hot techniques should be stopped on the basis of current evidence […] Further clinical research is needed to support the results of our study.”