Laparoscopic Entry Technique Using a Veress Needle Insertion with and without Concomitant CO2 Insufflation: A Randomized Controlled Trial

A novel less-traumatic needle for kidney puncture: first clinical experience

INTRODUCTION

To decrease complication rate, we developed a novel MG needle for kidney puncture consisting of a pointed cannula, an atraumatic mandrin-bulb and a spring mechanism pushing the mandrin-bulb forward.

AIM OF THE STUDY

To assess efficacy and safety of kidney puncture during percutaneous nephrolithotomy (PCNL) using a novel less-traumatic MG needle within a clinical trial.

MATERIALS AND METHODS

We conducted a prospective randomized single-center study. In the experimental group, kidney puncture was performed with a novel MG needle while in the control group, standard Trocar or Chiba puncture needles were used.

PRIMARY ENDPOINT

hemoglobin drop.

RESULTS

A total of 67 patients were enrolled. Patients who underwent standard puncture (n = 33) had higher hemoglobin drop in the early postoperative period (p = 0.024). Although there was no statistical difference in overall complication rate between the two groups (p = 0.351), two severe Clavien-Dindo IIIa complications with urinoma occurred in patients from the control group.

CONCLUSION

Less-traumatic needle for kidney puncture may reduce hemoglobin drop and prevent the development of severe complications. At the same time, in terms of stone-free rate (SFR), the efficacy of PCNL remains the same regardless of the needle used for renal access.

Needle-Probe Optical Coherence Tomography for Real-Time Visualization of Veress Peritoneal Needle Placement in a Porcine Model: A New Safety Concept for Pneumoperitoneum Establishment in Laparoscopic Surgery

The safe establishment of pneumoperitoneum is a critical step in all laparoscopic surgeries. A closed pneumoperitoneum is usually obtained by inserting a Veress needle into the peritoneal cavity. However, there is no definite measure to visually confirm the position of the Veress needle tip inside the peritoneal cavity. This study aimed to describe a method of real-time visual detection of peritoneal placement of the Veress needle using an incorporated optical coherence tomography (OCT) probe in a porcine model. A 14-gauge Veress needle was incorporated with a miniature fiber probe to puncture the piglet’s abdominal wall into the peritoneal cavity. A total of 80 peritoneal punctures were attempted in four piglets. For each puncture, continuous two-dimensional OCT images of the abdominal wall were acquired for real-time visual detection of the needle placement into the peritoneal cavity. Characteristic OCT image patterns could be observed during the puncturing process, especially a deep V-shaped concave pattern before the peritoneum puncture, which was a crucial feature. A statistical difference in the OCT signal standard deviation value also indicated the differentiability of images between the peritoneum and extra-peritoneal tissue layers. A success rate of 97.5% could be achieved with the guidance of the OCT images. OCT images translate the blind closed technique of peritoneal access into a visualized procedure, thus improving peritoneal access safety.

Preperitoneal insufflation pressure of the abdominal wall in a porcine model

BACKGROUND

Most complications and adverse events during laparoscopic surgery occur during initial entry into the peritoneal cavity. Among them, preperitoneal insufflation occurs when the insufflation needle is incorrectly placed, and the abdominal wall is insufflated. The objective of this study was to find a range for static pressure which is low enough to allow placement of a Veress needle into the peritoneal space without causing preperitoneal insufflation, yet high enough to separate abdominal viscera from the parietal peritoneum.

METHODS

A pressure test was performed on twelve fresh porcine carcasses to determine the minimum preperitoneal insufflation pressure and the minimum initial peritoneal cavity insufflation pressure. Each porcine model had five needle placement categories. One category tested the initial peritoneal cavity insufflation pressure beneath the umbilicus. The four remaining categories tested the preperitoneal insufflation pressure at four different anatomical locations on the abdomen that can be used for initial entry. The minimum initial insufflation pressures from each carcass were then compared to the preperitoneal insufflation pressures to obtain an optimal range for initial insufflation.

RESULTS

Increasing the insufflation pressure increased the probability of preperitoneal insufflation. Also, there was a statistically significant difference (p < 0.05) between the initial peritoneal cavity insufflation pressures (8.83 ± 4.19 mmHg) and the lowest preperitoneal pressures (32.54 ± 7.84 mmHg) (mean ± SD).

CONCLUSION

Pressures greater than 10 mmHg resulted in initial cavity insufflation and pressures greater than 20 mmHg resulted in preperitoneal insufflation in porcine models. By knowing the minimum pressure required to separate the layers of the abdominal wall, the risk of preperitoneal insufflation can be mitigated while obtaining safe and efficient entry into the peritoneal cavity. The findings in this research are not a guideline for trocar or Veress needle placement, but instead reveal preliminary data which may lead to more studies, technology, etc.