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

OBJECTIVE: To describe the surgical rectus sheath block for post-operative pain relief following major gynaecological surgery. TECHNIQUE: 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. STUDY DESIGN: 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. MAIN OUTCOME MEASURES: (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. RESULTS: 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. CONCLUSIONS: 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.

Delta sleep-inducing peptide alters bispectral index, the electroencephalogram and heart rate variability when used as an adjunct to isoflurane anaesthesia.

BACKGROUND AND OBJECTIVE: Delta sleep-inducing peptide (DSIP) is an endogenous peptide that crosses the blood-brain barrier, named after its association with natural sleep and enhanced electroencephalogram (EEG) delta rhythm. The objective of this study was to determine whether DSIP could be used as an adjunct to volatile anaesthesia in humans, our hypothesis being that DSIP is a natural hypnotic that would increase anaesthetic depth. The aims were to assess depth of anaesthesia using bispectral index (BIS), the EEG and heart rate variability (HRV), and to determine whether DSIP altered the symmetry of EEG between the left and right cerebral hemispheres. METHODS: Twenty-four female ASA I or II patients gave written, informed consent to a protocol approved by our local research ethics committee. Twelve were randomly assigned as controls to receive saline. The other 12 were randomly allocated to receive one of three intravenous bolus doses of DSIP (Clinalfa) at 25, 50 or 100 nmol kg(-1). The first administration of DSIP was while awake and the second after induction of anaesthesia with propofol and maintenance with isoflurane. BIS and EEG parameters were measured continuously using a bilateral electrode montage. RESULTS: DSIP significantly increased heart rate, decreased HRV and, paradoxically, significantly reduced delta rhythm along with reducing burst suppression and increasing BIS at 25 nmol kg(-1) during isoflurane anaesthesia. DSIP also significantly altered bilateral symmetry of EEG. CONCLUSION: DSIP probably reduced parasympathetic tone and decreased (lightened) the depth of anaesthesia measured using BIS.