Inguinal hernia repair: anaesthesia, pain and convalescence

Elective surgical repair of an inguinal or femoral hernia is one of the most common surgical procedures. The treatment, however, presents several challenges regarding anaesthesia for the procedure, the postoperative analgesic therapy and convalescence, as well as planning of the procedure. Local, general, and regional anaesthesia are all used for hernia repair, but to different degrees, primarily depending on traditions and whether the institution has specific interest in hernia surgery. Thus, the use of local anaesthesia varies from a few percent in Sweden, 18% in Denmark and up to almost 100% in specialised institutions, dedicated to hernia surgery. The feasibility of local anaesthesia is high, as judged by the rate of conversion to general anaesthesia (< 1%), although intraoperative pain is quite common. The generally low rate of serious complications does not allow firm conclusions, but the rate of less serious complications is lower by local anaesthesia, compared to other anaesthetic techniques. Of special interest is, that the rate of urinary retention can be eliminated by the use of local anaesthesia. Local anaesthesia results, in comparative studies, in a higher degree of patient satisfaction than other anaesthetic techniques. Local anaesthesia also facilitates faster mobilisation and earlier discharge/fulfilment of discharge criteria from post anaesthetic care units than other anaesthetic techniques. Pain after hernia repair is more pronounced at mobilisation or coughing than during rest, and younger patients seem to have more pain than older patients. The pain ceases over time, and it is most pronounced the day after surgery, where two thirds have moderate or severe pain during activity, while one third still have moderate or severe pain after one week, and approximately 10% after 4 weeks. Pain after laparoscopic surgery is less pronounced than after open surgery, while different open repair techniques do not exhibit significant differences. Postoperative pain is best treated with a combination of local analgesia and peripherally acting agents (paracetamol, NSAID or their combination), while opioids should be avoided due to side effects, primarily nausea and sedation. Moderate or severe pain one year postoperatively is seen in 5-12% of patients. There seem to be no difference between different surgical or anaesthetic techniques, but the following factors have been related to a higher rate of chronic pain: previous or subsequent hernia surgery on the same side, young age, pain before surgery, high pain scores in the immediate postoperative period, and postoperative complications and prolonged convalescence. Patients should be informed about the risk of chronic pain, particularly if the hernia is asymptomatic. The duration of convalescence after hernia repair varies considerably, primarily due to variation in recommendations. No documentation is available to support that a prolonged convalescence reduces the risk of recurrence of the hernia, and most specialised institutions recommend immediate return to all usual activities. Pain seems to be the most important cause of prolonged convalescence. From all published consecutive materials with recommendations of short convalescence the mean or median duration is 6-8 days, in contrast to the two to four weeks often seen in randomised comparisons of different surgical techniques. Patients should be informed, that they can immediately resume all activity if pain permits, but also to expect that pain may limit function of activities of daily living during the first postoperative week. Hernia surgery, including treatment of recurrent hernias, can and ought to be performed as day case surgery, irrespective of the chosen anaesthetic technique, as there are no medical or surgical contraindications to this. Social causes may indicate, that overnight stay may be advisable or desirable, preferably in a patient hotel facility. Despite this, the fraction of patients operated in a day-case surgical set-up varies from 6% in France to 83% in US, and in Denmark 60% of patients have their hernia repair as a day-case procedure. A day-case hernia surgery service should be organised with standardised patient records, including descriptions of surgery performed as well as letters of discharge for the general practitioner. If clinical data are stored electronically, the basis is created for valuable clinical databases like the one behind the present thesis, and they can be used both for scientific purposes and for quality control and improvement.