Interventional Treatment Modalities for Chronic Abdominal and Pelvic Visceral Pain

Efficacy and Safety of Paragastric Neural Blockade in Controlling Pain, Nausea, and Vomiting After Sleeve Gastrectomy: A Randomized Controlled Trial

BACKGROUND

There are difficulties in controlling the symptoms of pain, nausea, and vomiting after laparoscopic sleeve gastrectomy (LSG). This study aimed to evaluate the efficacy and safety of PGNB on pain and nausea and vomiting in the early postoperative period in patients who underwent LSG.

METHODS

In this prospective, randomized, controlled, double-blind study, the patients were divided into two equally formed groups: patients who underwent PGNB after LSG and the control group. Postoperative pain symptoms were evaluated using the visual analog scale (VAS) scores, and nausea and vomiting symptoms were evaluated using the postoperative nausea and vomiting (PONV) scores.

RESULTS

The study was completed with 90 patients, 45 patients in each group. The VAS scores measured at postoperative hours 1, 6, and 12 were statistically significantly lower in the PGNB group. There was no significant difference between the two groups in terms of the 24th hour VAS scores. The mean PONV scores of the PGNB and control groups were 0.47 ± 0.89 and 1.67 ± 1.95, respectively, revealing a significantly higher value for the controls. The mean time to first mobilization in the postoperative period was significantly shorter in the PGNB group. Upon the evaluation of patient satisfaction, it was determined that the satisfaction score of the PGNB group was significantly higher.

CONCLUSIONS

PGNB is an effective and safe method for managing pain, nausea, and vomiting that occur in the early period after LSG.

Paraventricular thalamus-insular cortex circuit mediates colorectal visceral pain induced by neonatal colonic inflammation in mice

AIMS

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder, but its pathogenesis remains incompletely understood, particularly the involvements of central nervous system sensitization in colorectal visceral pain. Our study was to investigate whether the paraventricular thalamus (PVT) projected to the insular cortex (IC) to regulate colorectal visceral pain in neonatal colonic inflammation (NCI) mice and underlying mechanisms.

METHODS

We applied optogenetic, chemogenetic, or pharmacological approaches to manipulate the glutamatergicPVT-IC pathway. Fiber photometry was used to assess neuronal activity. Electromyography activities in response to colorectal distension (CRD) were measured to evaluate the colorectal visceral pain.

RESULTS

NCI enhanced c-Fos expression and calcium activity upon CRD in the ICGlu, and optogenetic manipulation of them altered colorectal visceral pain responses accordingly. Viral tracing indicated that the PVTGlu projected to the ICGlu. Optogenetic manipulation of PVTGlu changed colorectal visceral pain responses. Furthermore, selective optogenetic modulation of PVT projections in the IC influenced colorectal visceral pain, which was reversed by chemogenetic manipulation of downstream ICGlu.

CONCLUSIONS

This study identified a novel PVT-IC neural circuit playing a critical role in colorectal visceral pain in a mouse model of IBS.

Novel Implantation Technique for Thoracoabdominal Peripheral Nerve Stimulation via a Transversus Abdominal Plane Approach for Treatment of Chronic Abdominal Pain

Background

Chronic abdominal pain (CAP) is a common and challenging to treat condition with a global prevalence of up to 25%. Despite extensive evaluation, approximately 40% of patients with CAP have an unknown diagnosis. Medications may be ineffective, and surgery is rarely indicated. Interventional treatment including sympathetic blocks, sympathetic neurolysis, and transversus abdominal plane (TAP) blocks may be an option, but their efficacy can wane over time. Neuromodulation has emerged as an option for these patients, as there is evidence of success with dorsal column spinal cord and dorsal root ganglion (DRG) stimulation. Peripheral nerve stimulation (PNS) may be an alternative option, particularly in higher risk patients or in patients for whom neuraxial access may be unsafe or too technically challenging. Thoracoabdominal nerve peripheral nerve stimulation via a TAP approach may be more specifically targeted in comparison to dorsal column or DRG stimulation. In this short report, we detail a technique that the authors have successfully used for thoracoabdominal nerve PNS via a TAP approach for management of CAP.

Methods

This article describes a novel medial to lateral ultrasound guided thoracoabdominal nerve PNS via a TAP approach technique for lead placement and implantation.

Results

A medial to lateral ultrasound guided TAP approach as described to successfully implant percutaneous thoracoabdominal nerve PNS leads for management of CAP.

Conclusion

The thoracoabdominal nerve PNS via a TAP approach lead placement technique noted in this report has been used as a means for management of CAP utilizing peripheral neuromodulation. Here, we present a short report detailing a potential technique for PNS utilization for management of CAP. Further studies are needed to validate the safety and efficacy of this therapy modality, although the authors have found it to be a viable management option for patients with medically refractory neuropathic CAP.

Chronic Abdominal Discomfort Syndrome (CADS): Defining and Discussing a Novel Diagnosis

In this article, we propose a new diagnostic paradigm known as Chronic Abdominal Discomfort Syndrome (CADS). Patient's presentation centers around chronic abdominal pain not explained by acute pathology with or without accompanying dyspepsia, bloating, nausea and vomiting among other symptoms. The pathophysiology is noted to be neurogenic, possibly stemming from visceral sympathetic nerves or abdominal wall afferent nerves. Diagnosis is supported by signs or symptoms traversing clinical, diagnostic and functional criteria. Included is a tool which can assist clinicians in diagnosing patients with CADS per those domains. We hope to facilitate primary care physicians' and gastroenterologists' utilization of our criteria to provide guidance for selecting which patients may benefit from further interventions or evaluation by a pain physician. The pain physician may then offer interventions to provide the patient with relief.

Neuraxial drug delivery in pain management: An overview of past, present, and future

Activation of neuraxial nociceptive linkages leads to a high level of encoding of the message that is transmitted to the brain and that can initiate a pain state with its attendant emotive covariates. As we review here, the encoding of this message is subject to a profound regulation by pharmacological targeting of dorsal root ganglion and dorsal horn systems. Though first shown with the robust and selective modulation by spinal opiates, subsequent work has revealed the pharmacological and biological complexity of these neuraxial systems and points to several regulatory targets. Novel therapeutic delivery platforms, such as viral transfection, antisense and targeted neurotoxins, point to disease-modifying approaches that can selectively address the acute and chronic pain phenotype. Further developments are called for in delivery devices to enhance local distribution and to minimize concentration gradients, as frequently occurs with the poorly mixed intrathecal space. The field has advanced remarkably since the mid-1970s, but these advances must always address the issues of safety and tolerability of neuraxial therapy.

Successful Dorsal Root Ganglion Stimulation for Chronic Pancreatitis: A Case Report

Chronic pancreatitis represents an inflammatory condition occurring from repetitive pancreatic inflammation episodes ultimately causing patients intractable pain alongside pancreatic insufficiency and as a result, reduced quality of life. In addition to alcohol and smoking cessation, patients with chronic pancreatitis are treated conservatively with anti-depressants, anti-convulsant and analgesic medications including paracetamol and celecoxib - with limited success. Alternative to surgical resection, patients can opt for endoscopic treatment options including sphincterotomy or removal of calculi which have shown limited success. Celiac plexus blocks have had positive outcomes as well, however, are not long-lasting and carry significant risks, such as gastroparesis or organ damage. Evidence has shown alterations in the peripheral and central nervous system which causes these patients to often experience dysfunctional and neuropathic pain. The advent of this knowledge has introduced neuromodulation into the field with successful cases of spinal cord stimulation treating the pain associated with chronic pancreatitis. Dorsal root ganglion stimulation is similarly based upon the gate theory of pain but with more precision as it strictly targets the dorsal root ganglion. There have been no cases reported in the literature of this form of stimulation in treating chronic pancreatitis. We present a case of a patient with chronic pancreatitis who obtained 80% abdominal pain relief for two years after undergoing dorsal root ganglion stimulation.