The Beneficial Effect of Quadratus Lumborum Block After Laparoscopic Cholecystectomy

QLB (quadratus lumborum block) is a recommended multimodal method of reducing postoperative pain in laparoscopic and open surgery. Quadratus lumborum block for postoperative pain after caesarean section 2015). Transversus abdominis plane (TAP) block seems to be feasible and effective in postoperative pain control without increasing morbidity in cholecystectomy. QLB is also performed as one of the perioperative pain management procedures in abdominal surgery. It is regarded as an effective analgesic tool The dermatomal effects of QLB reach higher than the TAP block and might explain the better effect of the QLB than TAP blocks on postoperative pain after caesarean delivery. A randomized double blinded clinical trial with TAP block in patients scheduled for cholecystectomy is performed, but there is no good data for the QLB. For this study the investigators standardize the type of surgery to be laparoscopic day-case cholecystectomy, and we use the anterior (transmuscular) QLB.

Power and Sample Size Calculator The number of patients required for the study was calculated on the basis of opioid consumption. The investigators are interested in a reduction by 20% in the group given QLB. Assuming α=0,05, the calculation shows a need of 69 patients (23 in each group) to achieve a power of 80% (β=0.2).

75 adult patients scheduled for cholecystectomy have to be included. Subcutaneous wound infiltration at the end of surgery in all patients with ropivacaine 2 mg/ml, 10 ml. Maximum allowed dosis is 3 mg/kg BW (BodyWeight). Dosis reduction if BW<70 kg. All three groups receive necessary analgesics oral or parenteral.

Premedication: Paracetamol 2g and Diklofenak 100 mg

General anesthesia: TCI (Target Control of Infusion): Propofol and Remifentanil, Ondansetron 4 mg and Decadron 8 mg iv preoperatively. Oxycodon 5 mg iv at the end of the procedure.

Surgical procedure: Cholecystectomy, laparoscopic and day-case.

Postoperatively:

• Oral paracetamol and codeine-fixed combination up to 1000 mg and 60 mg, respectively, every 6 h
• In case of insufficient analgesia, as judged by the patient, oxycodon 1 - 5 mg IV.
• When nausea and vomiting occur postoperatively, ondansetron 4 mg IV administers as the drug of first choice followed by droperidol 0,625 mg IV if the nausea/vomiting persists.

Collected data:

• Postoperative pain at rest and during activity evaluates by a 0 - 10 scale (NRS) on admission to recovery, and every hour until discharge.
• Rescue analgesic consumption during 0 to 4, 4 to 24 and 24 to 48 h.
• Nausea and vomiting record by the same 0 - 3 scale (none, slight, moderate, strong) during recovery
• Time of postoperative mobilization with corresponding pain score.
• Time of discharge-to-home readiness according to standard criteria, including stable vital signs, no bleeding from the surgical site, ability to void, absence of excessive nausea and pain, and ability to dress and walk without support.
• Side effects including nausea and/or vomiting (0 to 4, 4 to 24, and 24 to 48 h), and other side effects and symptoms of LA (Local Anaesthetic) toxicity.

Telephone interview at 24 h and 48 h

Inclusion criteria

• Age 18-80 Years
• BMI 20-35
• ASA physical status I-II

Exclusion criteria

• Allergy to local anaesthetics
• Chronic pain requiring opioid analgesics
• Patients with atrioventricular block II
• Patients treated with class III antiarrhythmics
• Patients with severe renal and/or hepatic disease
• A coagulation disorder
• An infection at the LA injection place