PQLB vs TFPB in HALDN

Hand-assisted laparoscopic donor nephrectomy (HALDN) is a widely used technique for kidney donor surgeries. Management of postoperative pain is important to provide patient comfort. Main components of postoperative pain is from incision sides. Regional anesthesia techniques may reduce postoperative opioid requirements in this patient group, but the optimal block for this procedure has not been established.

A competed but not yet published study in our clinic found that transversalis fascia plane block significantly reduced analgesic requirements after HALDN. Its a deep block, that involves injection below transversalis fascia and above perirenal fat tissue. Its location can be seen relatively close to the important structures of such as peritoneum and retroperitenoum. Posterior quadratus lumborum block (PQLB, also known as quadratus lumborum block -2 or QLB-2) is considered effective in renal surgery for other indications and PQLB may provide analgesia comparable to TFPB for HALDN surgery. Possible benefit of PQLB over TFPB is superficial anatomical location of PQLB and its relative distance to areas such as retroperitoneum and peritoneum. Results in our center shows TFPB effective in HALDN procedure, therefore it is selected as the control group intervention This trial is designed to determine whether PQLB is not inferior to TFPB for cumulative opioid consumption during the first 24 postoperative hours for HALDN surgery. Opioid consumption, pain scores and adverse effects through first 48 hours postoperatively and patient satisfaction at 48th hour will be evaluated as a secondary outcome to describe the duration of postoperative analgesic effect.

Routine preanesthetic premedication with midazolam 0.03 mg/kg will be administered to both study groups. Anesthesia will be induced with fentanyl 1-2 micrograms/kg IV, propofol 1-2 mg/kg IV, and rocuronium 0.9-1.2 mg/kg IV.

General anesthesia will be maintained with 40% inspired oxygen, desflurane at approximately 1 minimum alveolar concentration, and a remifentanil infusion at 0 - 0.02 micrograms/kg/min. The actual doses of all intraoperative opioids will be recorded. Intraoperative fentanyl and remifentanil administered before the end of surgery will not be included in the primary outcome.

The assigned block will be performed after induction of general anesthesia and before surgical incision, with the participant in the lateral position and the operative side facing upward.

Standard anesthesia monitoring will continue throughout block placement and until the surgery ends.

At the end of surgery, all participants will receive paracetamol 1 g IV and morphine 0.05 mg/kg IV in addition to regional anesthesia technique as standardized multimodal analgesia regiment. The end-of-surgery morphine dose will be included in cumulative postoperative opioid consumption.

Participants will be extubated in the operation room when clinically appropriate and transferred to the post-anesthesia care unit.

In the PACU, a morphine PCA device will be started using a 1 mg IV bolus, an 8-minute lockout interval, and no basal infusion. Device-generated records will be used to determine PCA consumption. In PACU, if NRS is greater than or equal to 4 is observed, fentanyl 50 micrograms IV will be administered up to three times at 15-minute intervals. All fentanyl administered in the PACU will be included in cumulative postoperative opioid consumption.

For 48 hours, all participants will receive paracetamol 1 g IV three times daily and morphine PCA using the same settings. In surgical ward, If NRS is greater than or equal to 4 is observed, tramadol 100 mg IV will be administered as rescue analgesia in accordance with institutional prescribing limits.

Every rescue dose and any additional analgesic treatment required for clinical care will be recorded. Tramadol will be converted to IV morphine equivalents and included in cumulative postoperative opioid consumption.

Morphine PCA cumulative consumption, rescue opioid and analgesic use, NRS at rest, NRS during cough, and opioid-related and block-related adverse events will be assessed at postoperative hours 1, 3, 6, 12, 24, and 48.

Patient satisfaction with postoperative pain management will be assessed at postoperative hour 48.

Protocol deviations, withdrawal, loss to follow-up, unblinding, and missing assessments will be recorded whenever they occur.