Perioperative truncal peripheral nerve blocks for bariatric surgery: an opioid reduction strategy.

BACKGROUND: Bariatric surgical patients are vulnerable to cardiopulmonary depressant effects of opioids. The enhanced recovery after surgery (ERAS) protocol to improve postoperative morbidity recommends regional anesthesia for postoperative pain management. However, there is limited evidence that peripheral nerve blocks (PNB) have added benefit. OBJECTIVE: Study the effect of PNB on postoperative pain and opioid use following bariatric surgery. SETTING: Academic medical center, United States. METHODS: We conducted a cohort study of patients who underwent sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB) surgery. A total of 44 patients received the control ERAS protocol with preoperative oral extended-release morphine sulfate (MS), while 45 patients underwent a PNB with either intrathecal morphine (IM) or oral MS per local ERAS protocol. The PNB group either underwent preoperative bilateral T7 paravertebral (PVT) PNBs (27 patients) with IM or postoperative transversus abdominis plane (TAP) PNBs (18 patients) with oral MS. The primary outcome compared total opioid consumption between the ERAS control group and the PNB group up to 48 hours postoperatively. Secondary outcomes included comparison by block type and postoperative pain scores. RESULTS: PVT or TAP PNB patients had a reduction in mean postoperative oral morphine equivalent (OME) requirements compared with the ERAS protocol cohort at 24 hours (93.9 versus 42.8 mg), P < .0001; at 48 hours (72.6 versus 40.5 mg); and in pain scores at 24 hours (5.64/10 versus 4.46/10), P = .02. OME and pain scores were higher in the SG cohort. CONCLUSION: Addition of truncal PNB to standard ERAS protocol for bariatric surgical patients reduces postoperative total opioid consumption.

Surgical placement of customized abdominal vagus nerve stimulating and gastrointestinal serosal surface recording electrodes.

Bioelectronic medical approaches to control vagus nerve-to-organ signaling have the potential to treat cardiac, respiratory, gastrointestinal (GI) and metabolic diseases, such as obesity. Unlike cervical vagus nerve stimulation (VNS), abdominal VNS could provide specific therapeutic control of the GI tract without off-target effects on thoracic organs; however, surgical approaches for abdominal VNS electrode placement are not well established. Moreover, optimal device configurations and additional placement of GI recording electrodes for closed-loop control are largely unknown. We designed VNS cuff and GI planar serosal electrodes and tested placement of these devices in laparoscopic surgery in two cadavers. We determined that electrode positioning on the ventral abdominal vagus nerve and gastric antrum was feasible but other sites, such as the duodenum and proximal stomach, were more difficult. The current investigation can guide potential placement and design of VNS cuff and GI electrodes for development of closed-loop GI therapeutic devices.

Auricular nerve stimulation using the NSS-2 BRIDGE device to reduce opioid requirement following laparoscopic Roux-en-Y gastric bypass.

BACKGROUND: Evidence supports the use of complementary techniques to reduce pain and opioid use after surgery. The NSS-2 BRIDGE device (NBD; Innovative Health Solutions, Inc., Versailles, Indiana) modulates pain via stimulation of the nucleus of the auricular branch of the cranial nerves at the level of the brainstem and the limbic system. OBJECTIVE: To investigate the role of auricular nerve field stimulation for pain control following gastric bypass surgery. SETTINGS: U.S. academic medical center. METHODS: A total of 18 subjects were included. Subjects were divided in 2 groups: NBD group (n = 8) and a control group (n = 10). The NBD was placed following laparoscopic Roux-en-Y gastric bypass (LRYGB) surgery in the recovery room. The effectiveness of NBD was assessed comparing the relative use of opioid consumption (oral morphine equivalents) and pain (0 = no pain to 10= worst possible pain) at 24 and 48 hours after surgery. In addition, the device tolerability (1-10) was assessed, with 8-10 considered excellent. Data were analyzed using unpaired t tests and presented as mean ± standard deviation. Alpha was set up at .1. RESULTS: Compared with the control group, the use of NBD was associated with a 60.2% reduction in oral morphine equivalents (38.15 vs 15.2 mg; P < .1) and a 28% reduction in pain (5.0 vs 3.6; P = .1) at 24 hours after surgery. The tolerability of NBD was reported to be excellent. CONCLUSIONS: This report suggests that NBD may represent an interesting alternative to control perioperative pain and limit opioid use following bariatric surgery. This needs to be confirmed by a placebo-controlled, randomized study.

Genetic and molecular abnormalities in cholangiocarcinogenesis.

Cholangiocarcinomas are biliary tree neoplasms of cholangiocyte origin. Several clinical risk factors are associated with cholangiocarcinogenesis. During the last decade, there has been an increasing interest in the causative molecular mechanisms of cholangiocarcinoma because of its poor prognosis and the lack of effective therapies. A better understanding of cholangiocarcinoma tumor initiation, promotion, and progression, as well as neurotransmitter, neuroendocrine, and endocrine growth effects, may elucidate molecular targets for diagnostic and therapeutic purposes.

Aberrant crypt foci as precursors in colorectal cancer progression.

Colorectal cancer progression originates when accumulated genetic and epigenetic alterations cause genomic instability and a malignant phenotype. Subsequent molecular pathway deregulation leads to histopathologic changes that are clinically evident as aberrant crypt foci (ACF) and visualized by high-magnification chromoscopic colonoscopy. ACF are biomarkers of increased colorectal cancer risk, particularly those with dysplastic features. Genetic profiling using genomic instability, loss of heterozygosity, and methylation analysis has revealed a minority population of ACF genotypically analogous to cancer.

Post-laparoscopic cholecystectomy pain: effects of intraperitoneal local anesthetics on pain control--a randomized prospective double-blinded placebo-controlled trial.

Postoperative pain after laparoscopic cholecystectomy (LC) is generally less than open cholecystectomy; however, the postoperative shoulder and abdominal pain experienced by patients still causes preventable distress. Intraperitoneal irrigation of the diaphragmatic surface and gallbladder fossa using normal saline, bupivacaine, or lignocaine may effectively control visceral abdominal pain after an LC. Two hundred patients with similar demographics undergoing elective LC were randomized to one of four groups of 50 patients each, including Group A placebo control, Group B with isotonic saline irrigation, Group C with bupivacaine irrigation, and Group D with lignocaine irrigation. All patients received preperitoneal abdominal wall infiltration with 0.25 per cent bupivacaine to control parietal (somatic) abdominal pain. The visual analogue and verbal rating pain scores at 0, 4, 8, 12 and 24 hours for both shoulder and abdominal pain were recorded in a prospective double-blind fashion at four points during the first 24 postoperative hours. Analgesia requirements, vital signs, blood glucose, and incidence of nausea and vomiting were also recorded. Patients in each group demonstrated a significant difference in visual analogue and verbal rating pain scores and analgesic consumption when compared with controls. Lignocaine controlled pain significantly better than saline or bupivacaine. Bowel function recovery was similar in all patients, and there were no significant complications. We conclude that intraperitoneal irrigation with either saline, bupivacaine, or lignocaine can significantly reduce visceral abdominal pain after LC. Lignocaine was the most efficacious local anesthetic in this trial and has a high safety profile when used at recommended doses.