Comparing Liposomal Bupivacaine VS Standard Bupivacaine in Colorectal Surgery

QL blocks will be done intraoperatively after induction. All procedures will be placed under
the supervision of the attending anesthesiologist on the acute pain service.

All patients will receive 1 gm acetaminophen and 600 mg gabapentin preoperatively. Patients
above 70yo will receive 300mg gabapentin. Patient will be randomized to one of the two arms.

For the QL block, Shamrock sign consistent of the quadratus lumborum muscle, psoas major
muscle, erector spinae muscles and the L4 transverse process will be identified. Under
ultrasound guidance with an in-plane technique, the needle will be advanced into the fascial
plane between the quadratus lumborum and psoas major muscles. For the LB group, 0.125%
bupivacaine 20ml plus Exparel®10ml will then be injected into the fascial plane on each side.
For the SB group. 30ml 0.25% bupivacaine will be injected on each side. Saline will be used
for hydro-dissection until the QL block target is confirmed on ultrasound.

As part of the ERAS protocol, all patients will receive ketamine and lidocaine drip during
surgery, which is the investigator's current standard of practice.

All patients will be scheduled on PO acetaminophen and PO gabapentin daily postoperatively
per ERAS protocol. PO oxycodone PRN will be started once patients tolerate diet. PRN IV
dilaudid may be given for severe breakthrough pain.

Opioid usage at 1, 24, 48 and 72 hours after the block will be recorded by a member of the
research team. Pain scores at rest and on movement (knee flexion) will be measured by the
investigator using Visual Analog Scale (VAS). Nausea will be measured using a categorical
scoring system (none=0; mild=1; moderate=2; severe=3). Sedation scores will also be assessed
by a member of the study team using a sedation scale (awake and alert=0; quietly awake=1;
asleep but easily roused=2; deep sleep=3). All these parameters will be measured at 1, 24, 48
and 72 hours after the QL block and patients will be encouraged to ambulate on postoperative
day 1 under supervision. Their ambulation activity will be recorded.

Inclusion criteria:

- Patients undergoing colorectal surgery at Indiana University Hospital

- ASA class 1, 2, 3 or 4

- Age 18 or older, male or female

- Desires Regional anesthesia for postoperative pain control

Exclusion criteria:

- Any contraindication for QL block.

- History of substance abuse in the past 6 months.

- Patients on more than 30mg morphine equivalents of opioids daily.

- Any physical, mental or medical conditions which in the opinion of the investigators,
may confound quantifying postoperative pain resulting from surgery.

- Known allergy or other contraindications to the study medications (Acetaminophen,
Gabapentin, Bupivacaine).

- Postoperative intubation.

- Any BMI greater than 40.0.