Postoperative pain is a major problem in patients who either donate a kidney or undergo kidney transplantation. This pain is commonly treated with opioids, which can cause several side effects, ranging from pruritus, impaired vigilance, and most concerning to severe respiratory depression. This can be aggravated in the recipient by accumulation of opioid metabolites secondary to renal impairment and secretion.

Several studies have shown an opioid sparing effect of a transversus abdominis plane (TAP) block after surgery in the lower abdomen. In the proposed study, we plan to compare the impact of an ultrasound guided single shot transversus abdominis plane (TAP) block versus a ultrasound guided sham block with normal saline (placebo) on postoperative pain scores, postoperative opioid consumption, as well as patient's satisfaction.

The investigators hypothesize, that patients who receive a TAP block will have lower postoperative pain scores, lower postoperative opioid consumption as well as higher satisfaction scores.

Inclusion Criteria:

• Age > 18 years, English speaking, receiving a kidney transplant or donating a kidney as part of standard clinical care

Exclusion Criteria:

• Allergy to local anesthetics or opioids, coagulopathy or dementia. Patients with known history of IV drug abuse and with very high preoperative opioid requirements (defined as > 120 mg oxycodone/ day, use of methadone or fentanyl patches) will also be excluded from this study.

Coagulopathy will be assessed by the patient's history and physical. Should there be concerns regarding "easy bleeding" or "easy bruising", further workup of the patient's coagulation will be ordered (PT, PTT, INR). Since we perform the TAP block after 3-4 hours of kidney surgery, any patient with coagulopathy will most likely have been canceled prior to surgery. Therefore, we would deem any patient, who was eligible for kidney surgery, eligible for a TAP block at the end of the surgical procedure.