Postoperative Pain After Pediatric Umbilical Hernia Repair

Recent studies on adult patients' perceptions of their hospital care have shown that
improvements are needed in pain management (Jha, Orav, Zheng, and Epstein). The use of
regional anesthetic techniques to block specific peripheral nerves in adult patients has
increased in recent decades as an alternative to general anesthesia or to decrease opioid use
during and after surgery. Decreased postoperative complications have been observed, with
fewer ambulatory patients requiring prolonged recovery room stays and/or costly unplanned
hospital admissions (Chan, Peng, Kaszas, Middleton, Muni, Anastakis, and Graham).

Regional anesthetic techniques have not been widely performed in pediatric patients because
of the challenge in requiring children to report paresthesias during needle placements.
However, pediatric anesthesiologists have recently begun to use ultrasound to identify
anatomy, and to guide needle insertion and local anesthetic infiltration, thereby enabling
peripheral nerve blocks to be performed safely in children under general anesthesia. Several
studies have illustrated that umbilical nerve blocks (Jose Maria, Götzens, and Mabrok) and
rectus sheath blocks (Willschke, Bosenberg, Marhofer, Johnston, Kettner, Wanzel, and Kapral)
can be used safely and effectively with ultrasound guidance in pediatric outpatient surgery.
To date, few studies have explored whether ultrasound-guided regional blocks of the abdomen
in children have the desired outcome of reducing postoperative pain and/or decreasing opioid
use.

The use of ultrasound to guide the deposition of local anesthetic in the posterior sheath of
the rectus muscle containing the peripheral nerves that innervate the abdomen may decrease
postoperative pain, opioid and non-opioid analgesic consumption, as well as minimize
opioid-related complications. Currently, at Children's Hospital Boston, the most common
regimen for pain control after umbilical hernia repair performed under general anesthesia
(i.e. standard of care) has been surgeon-administered nonspecific local anesthetic
infiltration in the wound at the conclusion of surgery, followed by opioids in the
Post-Anesthesia Care Unit and an oral opioid/acetaminophen combination post-discharge. In
sporadic cases over the past year, several pediatric surgeons have collaborated with
anesthesiologists from the pain service to allow ultrasound-guided bilateral rectus sheath
blocks to be performed in patients undergoing umbilical hernia repair, usually prior to the
surgical repair, and often concomitantly with surgeon-administered local anesthetic
infiltration in the wound. Because of the anecdotal nature of these practices, specific
conclusions regarding improvements in post-operative pain or decreased need for
post-operative opioid use cannot be drawn. However, anecdotal reports from parents at the
time of outpatient post-operative follow-up visits have been encouraging regarding perceived
success in achieving adequate post-operative pain control in patients receiving the regional
block.

We propose an interdisciplinary, prospective, randomized, single-blinded clinical trial of
the use of ultrasound-guided bilateral rectus sheath blocks versus local anesthetic
infiltration in a pediatric population of patients undergoing ambulatory umbilical hernia
repair at Children's Hospital Boston and Children's Hospital Boston at Waltham.

Inclusion Criteria:

- Any patient who is 3 to 12 years of age

- Any patient undergoing outpatient umbilical hernia repair

- Any patient capable of expressing pain using the Faces Pain Rating Scale

- Patient has provided assent (if age 10 or older)

- Parents/guardians have provided informed consent

Exclusion Criteria:

- Any patient classified as ASA III, IV, or V by the American Society of
Anesthesiologists

- Any patient with a history of Complex Regional Pain Syndrome

- Any patient with a history of chronic analgesic use

- Any patient who has used an analgesic including opioids, acetaminophen, and/or NSAID's
within 24 hours prior to surgery

- Wards of the state

- Any patient with an incarcerated umbilical hernia requiring emergent surgery

- Any patient who does not speak English or Spanish

- Any patient whose primary caregiver does not speak English or Spanish

- Any patient who cannot express pain using the Faces Pain Rating Scale due to a
disability

- Any patient whose primary caregiver is unable to comply with home instructions due to
a disability

- Any patient less than 3 years of age or greater than 12 years of age

- Any patient with renal insufficiency

- Any patient with a bleeding disorder