The surgical rectus sheath block for post-operative analgesia: a modern approach to an established technique

To describe the surgical rectus sheath block for post-operative pain relief following major gynaecological surgery.

Local anaesthetic (20 ml 0.25% bupivacaine bilaterally) is administered under direct vision to the rectus sheath space at the time of closure of the anterior abdominal wall.

We conducted a retrospective case note review of 98 consecutive patients undergoing major gynaecological surgery for benign or malignant disease who received either standard subcutaneous infiltration of the wound with local anaesthetic (LA, n=51) or the surgical rectus sheath block (n=47) for post-operative pain relief.

(1) Pain scores on waking, (2) duration of morphine-based patient controlled analgesia (PCA), (3) quantity of morphine used during the first 48 post-operative hours and (4) length of post-operative stay.

The groups were similar in age, the range of procedures performed and the type of pathology observed. Patients who received the surgical rectus sheath block had lower pain scores on waking [0 (0-1) vs. 2 (1-3), p<0.001], required less morphine post-operatively [12 mg (9-26) vs. 36 mg (30-48), p<0.001], had their PCAs discontinued earlier [24h (18-34) vs. 37 h (28-48), p<0.001] and went home earlier [4 days (3-4) vs. 5 days post-op (4-8), p<0.001] [median (interquartile range)] than patients receiving standard subcutaneous local anaesthetic into the wound.

The surgical rectus sheath block appears to provide effective post-operative analgesia for patients undergoing major gynaecological surgery. A randomised controlled clinical trial is required to assess its efficacy further.