Efficacy of Transversus Abdominis Plane Block

Overview

This study aims to assess the efficacy of Transversus Abdominus Plane (TAP) blocks, a well-established anesthetic technique, to decrease the amount of post-operative pain in patients who undergo minimally invasive gynecologic surgeries. During minimally invasive gynecologic surgeries, the abdomen is inflated with pressurized air for visualization purposes and released at the end of the surgery. Traditionally, TAP blocks are performed by injecting long-acting local anesthetic agents under ultrasound guidance into the abdominal wall after abdominal surgery after the air has been emptied from the abdomen for additional anesthetic coverage post-operatively. This study proposes a novel approach: that performing TAP blocks while the abdomen is still insufflated will result in better post-operative pain outcomes as compared to the traditional method.

Background Every year 15 million laparoscopic procedures are performed globally, with 4,800,000 or 32% of procedures performed in the U.S. alone. This minimally invasive procedure is one of the most common surgical procedures in the United States. Approximately 350,000 or half of all bilateral tubal sterilizations are performed laparoscopically; almost two-thirds of the 600,000 hysterectomies are performed via laparoscopy. Laparoscopy is also commonly used for diagnostic purposes, and to perform other common procedures such as treatment for endometriosis and lysis of adhesions. During laparoscopic gynecologic surgeries, the surgical team will have the abdomen inflated with pressurized carbon dioxide for surgical visualization purposes which is then released at the end of the surgical procedure. For many laparoscopic procedures, a transversus abdominis plane block (TAP) block using a long-acting local anesthetic is used to manage pain performed outside the OR, more for logistical ease, traditionally this block is performed outside the operating room setting, in the post-operative period on a non- insufflated abdomen under ultrasound guidance. Rationale for conducting the research. This study has two major aims; 1) to determine whether post-operative TAP blocks performed in an insufflated abdomen will result in more optimal postoperative pain control compared to TAP blocks performed in the traditional method in a non-insufflated abdomen and 2) to observe if performing the TAP block in a insufflated abdomen will be more clinically efficient to perform than the traditional method performed in a non-insufflated abdomen. The study hypothesis is that the study group receiving the TAP block the insufflated abdomen will have more optimal postoperative pain control, requiring less adjuvant pain medication as compared to the participants receiving the control intervention. Additionally, we hypothesize that the proceduralist will be able to perform a TAP block in less time with and with few attempts in the insufflated compared to the non- insufflated abdomen group due to better visualization of the anatomical planes from insufflation of the abdominal area. The results of this study may add additional clinically effective practice guidelines for both regional anesthesia and acute pain management relating to laparoscopic gynecological procedures. Furthermore, TAP blocks performed under insufflation may provide a viable method for decreasing opioid use and reducing potential opioid dependence in patients following surgical intervention.