Midpoint Transverse Process to Pleura Block for Postoperative Analgesia in Laparoscopic Cholecystectomy: A Pilot Study and Review of Literature

Abstract

Abstract Background: Midpoint transverse process to pleura block (MTPB) provides a close anatomical alternative to paravertebral block (PVB). The extent of the drug spread in MTPB and analgesic equivalence of MTPB with PVB and other “paravertebral by proxy” blocks are still under study. Methodology: Ten patients posted for elective laparoscopic cholecystectomy were administered general anesthesia, followed by bilateral ultrasound-guided MTPBs. A total of 20 mL of the drug mixed with iohexol dye solution was injected in each block. Postoperative pain scores were assessed. The spread of drug dye solution under ultrasound and fluoroscopy was studied. Results: Eighty percent of patients had NRS < 3 in the postanesthesia care unit. “Pain score” at 24 h was 2 for three patients and 1 for all other patients. The dye spread under fluoroscopy was observed to extend up to 5–7 levels of cephalad and 5–6 levels of caudad from the point of injection. Sonographic drug spread in the paravertebral space was visualized in 13 out of 20 (65%) blocks. Conclusion: With the results of our study and review of literature, it reflects that MTPB is an effective analgesic adjunct in thoracic surgeries and appears promising in abdominal surgeries as well. In laparoscopic cholecystectomies, its potential role in reducing shoulder pain should be explored further. Currently, it is not possible to recommend MTPB over PVB or erector spinae plane block (ESPB). Yet, it is to acknowledge the presence of the “midpoint transverse process to pleura” area as a definite injection target, which may confer some advantages over PVB and ESPB.