Awake Caudal Catheter Infusion Versus General Anesthesia

Awake Caudal Catheter Infusion Versus General Anesthesia and Single-dose Caudal Injection for Preterm NICU Patients Undergoing Inguinal Herniorraphy.

It is well established that preterm inguinal hernias discovered in the NICU pose a significant surgical risk due to the associated co-morbid conditions that accompany these patients. Currently, the standard of care in the United States is general anesthesia. There have been studies that have established that elective outpatient repair of inguinal hernias found in the NICU can be safely performed. Patients that are ready for discharge from the NICU will have inguinal hernia repair prior to leaving. Inguinal hernia repair will also be done on those premature infants that are seen in the Nemours surgical clinic. Spinal anesthesia is currently the most common anesthetic procedure used in the surgical treatment of preterm inguinal hernias after general anesthesia. Caudal catheter technique has been proven to safely provide post-operative care of premature infants. The caudal catheter technique involves placement of a small catheter under ultrasound guidance into the caudal epidural canal to allow re-dosing of local anesthetic during the case and has been shown to be safe and effective management in neonates (Somri M, 2007).

This is a prospective, blinded, randomized controlled trial evaluating the effectiveness of awake caudal catheter infusion versus single dose caudal injection and general anesthesia in the surgical management of preterm infant inguinal hernia repair. Spinal anesthesia has been advocated for but highly rejected in the pediatric surgical community due to its high failure rate, which can be up to 28%. Spinal anesthesia is a form of regional anesthesia involving injection of a local anesthetic into the subarachnoid space, via a fine needle, in a single injection. The failure rate has to do with the time constraint of spinal anesthesia, which is approximately 1 hour. It is difficult to perform a bilateral inguinal hernia in that time duration, necessitating a return trip to the operating room for the contralateral side or intubation midway through the surgical case. An alternative to spinal anesthesia that results in an ability to sustain regional anesthetic effect for a longer duration is the caudal catheter infusion. We hypothesize that awake caudal catheter infusion will allow for the following benefits (1) greater than 2 hour anesthetic time via re-dosing which will allow for the completion of the planned surgical procedure (2) exhibit a negligible failure rate (3) minimize post-operative complications that have been associated with general anesthesia in the preterm neonate.

The statistician for the study will generate a randomization table. An unblinded research coordinator will prepare randomization envelopes which will be numbered sequentially and placed in a bin located in the secure medication room in the peri-operative suite.Intra-operatively, neither the anesthesiologist nor the surgeon will be blinded since they are present from the induction of anesthesia until the conclusion of the operation for patient safety. The doctors, nurses and others caring for the infant postoperatively will be blinded.

For caudal infusion group: bupivacaine .3% + 1: 200,000 epinephrine (dose 3mg/kg) will be administered via the catheter. For general anesthesia group: bupivacaine 0.25% + 1:200,000 epinephrine (total dose 2.5mg/kg) prior to start of the surgery.

Cessation of breathing by a premature infant that lasts for more than 20 seconds and/or is accompanied by hypoxia or bradycardia.

Inclusion Criteria: Preterm infants less than 60 weeks post gestational age born at less than 37 weeks gestational age. Patients in the NICU will meet discharge criteria with or without supplemental oxygen prior to surgical scheduling for inguinal hernia repair. Exclusion Criteria: Patient undergoing other invasive procedures (i.e. gastrostomy tube placement, tracheostomy, laser eye treatment) Medical condition that would prevent a regional anesthetic from being performed (i.e. bleeding diathesis, vertebral anomalies, and spinal cord injury prior to surgery) Contradictions to the prescribed medications in the protocol.