transversus abdominis plane (tap) versus local anesthetic for lap appendectomies

Conditions: Appendicitis

Summary: this study is a prospective, double-blinded, randomized comparison of 2 patient cohorts. one group of patients will receive a transversus abdominis plane (tap) block. the second group will receive local anesthetic infiltration injected at the surgical site by the surgeon at the end of surgery for a laparoscopic appendectomy. the purpose of this study is to prospectively compare post-operative pain relief in pediatric patients undergoing laparoscopic appendectomy who have received either a transversus abdominis plane (tap) block or local anesthetic infiltration by the surgeon for analgesia to compare the most appropriate delivery of effective analgesia. in an effort to improve postoperative analgesia while limiting opioid-related adverse effects, there continues to be an increased use of multimodal techniques in infants and children.

the literature has clearly demonstrated that the effective treatment of postoperative pain in infants and children is challenging. despite the recognition of the importance of postoperative analgesia and the potential adverse effects of postoperative pain, significant pain occurs during the postoperative period in both the inpatient and outpatients settings. specifically, appendectomy is one of the most common pediatric surgical procedures and is associated with significant postoperative pain. additionally, although the use of opioid analgesics is generally safe, adverse effects do occur thereby mandating the use of alternative analgesic techniques when feasible. in an effort to improve postoperative analgesia while limiting opioid-related adverse effects, there continues to be an increased use of multimodal techniques in infants and children. these can include tap block as well as wound infiltration with local anesthetic. the efficacy of tap blocks in the setting of laparoscopic appendectomy has been demonstrated in both adult and pediatric populations, however its efficacy in comparison to local anesthetic infiltration is unclear. the tap block was first described by mcdonnell et al. in 2004 for pain control of procedures involving the anterior abdominal wall. the skin, muscles, and parietal peritoneum in this region are innervated by the t7 through l1 nerve roots. the authors described deposition of local anesthetic in the plane between the internal oblique and the transversus abdominis muscle where the terminal branches of the t7 through l1 nerves lie. since then, the tap block has been shown to effectively provide analgesia for a variety of abdominal procedures. in 2007 an ultrasound guided approach was described by hebbard et al. with a subsequent study concluding that an ultrasound guided tap block provided superior analgesia than a blind technique. the frequency of surgical appendectomy in both the inpatient surgical as well as the ambulatory setting justifies this comparison of effective analgesia. this study can certainly change the daily practice of the pediatric anesthesiologist in providing optimal care in patient and family satisfaction, as well as recovery.

Eligibility criteria:
inclusion criteria: * asa physical status i or ii * patients \> 4 years of age * weight less than or equal to 60 kg * presenting for laparoscopic appendectomy exclusion criteria: * asa physical status \> ii * patients \< 4 years of age * weight greater than 60 kg * patients presenting for ruptured appendectomy surgical procedures * co-morbid diseases (cardiac, pulmonary (not including asthma), neurological disease) * patients having concomitant procedures (circumcision, orchiopexy, etc.)

Keywords: transversus abdominis plane block tap block local anesthetic infiltration appendectomy laparoscopic appendectomy