[Forefoot surgery under regional anesthesia].

PURPOSE OF THE STUDY: The aim of this study is to present the method of lower limb peripheral nerve block for forefoot surgery and, in comparison with other methods, to evaluate the results in terms of postoperative analgesia and postoperative complications.

MATERIAL: Our group included 164 patients, 13 men and 151 women in the age range from 16 to 79 years, who underwent surgery for forefoot deformities during the years 1998-99. Of these, 77 (46 %) were operated on under general anesthesia, 54 (33 %) under infiltration anesthesia and 33 (21 %) under peripheral nerve block.

METHODS: When peripheral nerve block was used, the anesthetic Marcain was administered about 1 hour before surgery at the following sites: along the deep branch of the peroneal nerve on the dorsal side of the foot, along the tibial nerve behind the inner ankle, and along the sural nerve in the outer ankle region. After surgery, the duration of requirement for analgesia in all three types of anesthesia was recorded. Complications associated with wound healing were also recorded. Subjective satisfaction of the patients was evaluated as a separate issue.

RESULTS: No intraoperative complications were found in the patients operated on under peripheral nerve block. In three patients, regional anesthesia was not sufficient and had to be completed with topical anesthetics administered during the operation. The patients treated under regional anesthesia asked for analgesics after an average of 9.5 hours; those operated on under infiltration and general anesthesia required analgesics at an average of 2.5 hours (range, 2 to 4 hours) and within 30 min of waking up, respectively. Complications associated with wound healing were recorded in 5 %, 11 % and 6 % of the patients treated under general, infiltration and regional anesthesia, respectively. Of the 33 patients operated on under regional anesthesia, 28 would prefer this anesthesia for any other similar surgery and five would rather have general anesthesia.

DISCUSSION: Regional anesthesia is associated with fewer complications of wound healing than topical anesthesia, which is apparently due to a lower degree of ischemia produced in the treated limb by peripheral nerve block. Healing after regional anesthesia is only a little worse than after general anesthesia, but with the absence of risks related to general anesthesia. Patients operated on under general anesthesia feel pain immediately after surgery, those receiving infiltration anesthesia ask for painkillers at an average of 2.5 hours and, with well-introduced regional anesthesia, patients are free from pain for 9.5 hour on the average. The duration of postoperative pain absence is also related to the anesthetic used. The use of 1 % Mesocain results in a fast onset of anesthesia but its effect is shorter, while 0.5 % Marcain has a slower onset but a longer effect.

CONCLUSIONS: Regional anesthesia for forefoot surgery, if the anesthetic is well administered, is one of the options associated with minimal risks. It apparently reduces complications of wound healing, when compared with infiltration anesthesia. It can be used in situations where general anesthesia would put the patient at risk. It also has a pronounced analgesic effect that persists well after surgery and provides better postoperative comfort for the patient. Key words: lower limb, peripheral nerve block, forefoot surgery.