Percutaneous endoscopic gastrostomy under steady pressure automatically controlled endoscopy: First clinical series

Translation from manual to automatic endoscopic insufflation enhanced by a pressure limiter

BACKGROUND

Optimal visualization and safety have always been essential in performing any type of endoscopic surgery. However, the safety of automatic gastrointestinal (GI) insufflation has yet to be thoroughly studied, especially when combined with manual insufflation. The current study aimed to verify whether the pressure limiter could lower GI endoluminal pressure during endoscopic procedures and affect the behavioral patterns of endoscopists.

METHODS

A preclinical blinded trial was conducted on endoscopists who had no knowledge regarding the presence of the pressure limiter that prevents a GI endoluminal pressure above 25 mmHg. Endoscopists in group A performed esophageal endoscopic submucosal dissection (ESD) with our insufflation device equipped with the pressure limiter, whereas those in group B performed the same procedure without the pressure limiter. During all procedures, endoluminal pressure was continuously monitored. The primary endpoint of the current study was to measure the endoluminal pressure with or without the pressure limiter during esophageal ESD, while the secondary endpoint was to evaluate the effect of the pressure limiter on intraesophageal pressure and perioperative outcomes during esophageal ESD. A questionnaire survey was conducted after each session.

RESULTS

A total of 79 endoscopists were included in this randomized control study. Group A had significantly lower endoluminal pressure than group B (10.6 ± 4.61 vs. 16.25 ± 7.51 mmHg, respectively; p < 0.05). Although two pigs in group B died from tension pneumothorax, none in group A died. Evaluation of lumen expansion, ease of aspiration, and visual field reproducibility were poorer in group A than in group B, although all fell within the acceptable range. Subjective evaluation of usability was divided into two categories, Excellent/Good and Poor/Bad, with no significant differences in any of the items.

CONCLUSIONS

This preclinical study showed that endoscopic treatment with an automatic insufflation system could be performed at lower endoluminal pressure with a pressure limiter, which had no adverse effects on the endoscopist's feels on endoscopic procedures with the device.

A Preclinical Feasibility Study of Endoscopic Barostat: A Possible Diagnostic Tool for Visceral Hypersensitivity in Functional Dyspepsia

INTRODUCTION

Diagnosing functional dyspepsia requires excluding organic disease and gastrointestinal function evaluation; however, there are no modalities to evaluate these simultaneously. This preclinical study examined the possibility of an endoscopic barostat.

METHODS

Ultrathin endoscopy and our newly developed pressure-regulated endoscopic insufflator, which insufflates the gastrointestinal tract until the preset pressure is achieved, were used. The actual intragastric pressure was measured using an optical fiber manometer placed in the stomach. Experiment-1: in an ex vivo experiment, we insufflated the isolated stomach and verified whether the intragastric pressure reached the preset pressure. Experiment-2: we inserted the endoscope orally in a porcine stomach, insufflated the stomach, and verified whether the intragastric pressure reached the preset pressure. Finally, we insufflated the stomach at a random pressure to verify the functional tests for proof-of-concept.

RESULTS

Experiment-1: the intragastric pressure reached the preset pressure. After reaching the plateau, the pressure remained stable at the preset pressure (Huber M value: 1.015, regression line: 0.988, 95% confidence interval [CI]: 0.994-0.994). Experiment-2: the intragastric pressure reached the preset pressure. After reaching the plateau, the pressure remained stable at the preset pressure (Huber M value: 1.018, regression line: 0.971, 95% CI: 0.985-0.986). At randomly preset pressures, the transendoscopic theoretical intragastric pressure detected by using the insufflator was correlated with the actual pressure measured by using the pressure manometer.

CONCLUSIONS

This proof-of-concept study shows that a pressure-regulated endoscopic insufflator provides stable intragastric pressure at the preset level, with the potential of an endoscopic barostat to assess the visceral hypersensitivity related to functional dyspepsia.

Optimization of insufflation and pressure control in third-space endoscopy

BACKGROUND

Third-space endoscopy requires a delicate and accurate insufflation technique to secure the endoscopic visualization and maintain the working space. However, optimal third-space insufflation parameters have yet to be determined. The aim of this study was to assess: (1) the diversity of endoluminal third-space pressure by manual insufflation, and (2) the performance of the insufflation settings for third-space endoscopy.

METHODS

A submucosal tunnel was created in the upper posterior wall of the porcine stomach. Using two-channel esophagogastroduodenoscopy, one channel was used for insufflation and the other was used for pressure measurement. Experiment 1 Endoluminal submucosal tunnel pressure was measured in a 10-cm submucosal tunnel of a single porcine. Six board-certified endoscopists in turn maintained what they considered sufficient exposure under manual insufflation. Experiment 2 Endoluminal submucosal tunnel pressure and number of insufflations were measured using the pressure-regulated insufflation device; the differences in the submucosal tunnel length (long: 10-cm, short: 4-cm) and the insufflation route diameter (large: 3.8-mm, small: 2.2-mm) were compared.

RESULTS

Experiment 1 The endoluminal submucosal tunnel pressure profiles during third-space endoscopy varied between endoscopists. Experiment 2 Longer submucosal tunnels and larger insufflation route diameters lead to stable endoluminal submucosal tunnel pressure. The gap with the preset pressure of the insufflator and endoluminal pressure narrowed, and the required number of insufflations decreased with longer tunnel length and larger route diameter.

CONCLUSIONS

The pressure dynamics in third-space endoscopy differed among endoscopists. Longer submucosal tunnels and larger insufflation route diameters lead to stable endoluminal submucosal tunnel pressure.

The endoluminal pressures during flexible gastrointestinal endoscopy

In flexible gastrointestinal (GI) endoscopy, endoscopic insufflation is crucial and directly affects visualization. Optimal visualization enables endoscopists to conduct better examinations and administer optimal treatments. However, endoscopic insufflation is typically performed manually and is subjective. We aimed to measure the GI endoluminal pressure during flexible GI endoscopy. Participants underwent esophagogastroduodenoscopy (EGD) at our endoscopy center. Pressure measurement was conducted after completing diagnostic or follow-up EGD. The endoluminal pressure in the esophagus and stomach was measured at 1-s intervals for 1 min while performing EGD for observational and diagnostic purposes. During the measurements, the endoscopists maintained what they subjectively considered to be adequate exposure for screening for lesions by dilating the lumen. Eighty patients were enrolled in this study. The upper GI endoluminal pressure was assessed during EGD without adverse events. The esophageal endoluminal pressure averaged 8.9 (- 3.0 to 20.7) mmHg, and the gastric endoluminal pressure averaged 10.0 (3.0-17.9) mmHg; the upper GI endoluminal pressures were not affected by patient-related factors or the number of endoscopists' postgraduate years. We have successfully obtained the GI endoluminal pressures during EGD. Further accumulation of these data may lead to more stable and reproducible flexible endoscopic diagnosis and intervention.

Percutaneous transgastric endoscopic tube ileostomy in a porcine survival model

AIM

To introduce natural orifice transgastric endoscopic surgery (NOTES) tube ileostomy using pelvis-directed submucosal tunneling endoscopic gastrostomy and endoscopic tube ileostomy.

METHODS

Six live pigs (three each in the non-survival and survival groups) were used. A double-channeled therapeutic endoscope was introduced perorally into the stomach. A gastrostomy was made using a 2-cm transversal mucosal incision following the creation of a 5-cm longitudinal pelvis-directed submucosal tunnel. The pneumoperitoneum was established via the endoscope. In the initial three operations of the series, a laparoscope was transumbilically inserted for guiding the tunnel direction, intraperitoneal spatial orientation and distal ileum identification. Endoscopic tube ileostomy was conducted by adopting an introducer method and using a Percutaneous Endoscopic Gastrostomy Catheter Kit equipped with the Loop Fixture. The distal tip of the 15 Fr catheter was placed toward the proximal limb of the ileum to optimize intestinal content drainage. Finally, the tunnel entrance of the gastrostomy was closed using nylon endoloops with the aid of a twin grasper. The gross and histopathological integrity of gastrostomy closure and the abdominal wall-ileum stoma tract formation were assessed 1 wk after the operation.

RESULTS

Transgastric endoscopic tube ileostomy was successful in all six pigs, without major bleeding. The mean operating time was 71 min (range: 60-110 min). There were no intraoperative complications or hemodynamic instability. The post-mortem, which was conducted 1-wk postoperatively, showed complete healing of the gastrostomy and adequate stoma tract formation of ileostomy.

CONCLUSION

Transgastric endoscopic tube ileostomy is technically feasible and reproducible in an animal model, and this technique is worthy of further improvement.