Over 60 000 primary inguinal hernia repairs are carried out in England each year. Most of these are in men. Urinary retention, that is the inability to pass urine, after groin hernia surgery is not uncommon. The reported incidence varies from less than 5% to nearly 25%. The risk of urinary retention increases with age. It is also more if patients have any urinary symptoms already.
Why is it important?
Urinary retention may result in some patients requiring catheterisation and spending longer in the hospital. In some cases, patients may require further surgical procedures to allow them to pass urine again.Urinary retention is one of the most common causes of delayed discharge after groin hernia surgery.
Why do patients get urinary retention after hernia surgery?
Patients may develop urinary problems after inguinal hernia surgery as a result of overstimulation of muscle in the bladder neck and prostate causing an obstruction.There are some drugs that can block stimulation of these muscles.
These drugs are already used for treating urinary symptoms in men. They are known as alpha-blockers and the commonest used one in use in the UK is Tamsulosin.
Can drugs help prevent urinary retention?
A study published in the American Journal of Surgery last year by Clancy and colleagues, from Ireland, has suggested drugs might help.
They conducted a meta-analysis which involved pooling data from 5 previous studies that had compared treatment with an alpha-blocking drug to no treatment at all for patients undergoing open groin hernia surgery under general and spinal anaesthetic.
Their study concluded that the use of the alpha-blocking drug reduced the risk of postoperative urinary retention by just over 20%. There were limitations to this study, not all the blocking drugs were the same in each study. The studies included were quite small and comprised only 456 patients it total. The techniques of hernia repair differed between some of the studies. The type of anaesthetic used also differed between some of the studies.
Alpha-blocking drugs can have side effects. The commonest side effect is low blood pressure on standing or a headache. These side effects were found to be uncommon.
Despite the shortcomings, this is an interesting study. A larger study in older men needs to be carried out before any definitive recommendation can be made about the routine use of alpha-blockers in patients undergoing hernia surgery.
All patients should certainly be warned of the risks of urinary retention after hernia surgery.