Assessment of the aerosol distribution pattern of a single-port device for intraperitoneal administration of therapeutic substances.

BACKGROUND: In the last 20 years, intraperitoneal chemotherapy (IPC) has been explored as a modality for the management of peritoneal metastases of gynecologic, gastrointestinal, and primary peritoneal tumors. Direct delivery of chemotherapeutic agents to the peritoneal cavity space has proved superior to systemic chemotherapy when evaluating characteristics such as drug concentration reached in the peritoneal space, penetration into peritoneal metastases, and chemotherapy-related toxicity. Traditionally, IPC is delivered by peritoneal lavage with a liquid solution. This form of delivery has limitations, including inhomogeneous intraperitoneal distribution and limited ability to penetrate tissues and metastatic nodules. An alternative mode of delivery is so-called pressurized intraperitoneal aerosol chemotherapy (PIPAC). Within this context, the present study sought to identify the pattern of spatial distribution of therapeutic solutions aerosolized into the peritoneal space using a single-port PIPAC device and ascertain whether the aerosolized method is superior to the traditional (liquid) mode of IPC delivery. METHODS: Analysis of the rate of intra-abdominal staining with aerosolized 2% silver nitrate in five porcine models. RESULTS: Assessment of differences in stain impregnation between the upper, middle, and lower abdomen did not reveal significant differences (p = 0.42). The median sum scores were 1 for the upper abdomen and 3 for the middle and lower abdomen. CONCLUSIONS: Aerosolization does not reach all regions of the abdomen homogeneously. However, adequate exposure of the upper abdomen, mid-abdomen, and lower abdomen to chemotherapeutic agents can be achieved with PIPAC.

A novel percutaneous magnetically guided gastrostomy technique without endoscopy or imaging guidance: a feasibility study in a porcine model.

BACKGROUND: In order to simplify a percutaneous gastrostomy procedure and avoid the need of endoscopy or imaging methods, a novel percutaneous magnetically guided gastrostomy (PMG) technique was conceived. The aim of the present study is to evaluate the feasibility of a novel PMG technique with no endoscopy or any imaging guidance in a porcine model. METHODS: Fourteen crossbred domestic pigs were used for prototype development (cadaveric experiments) and proof-of concept, survival study. The magnetic device was conceived using commercially available rare-earth neodymium-based magnets. The experimental design consisted of developing an internal magnetic gastric tube prototype to be orally inserted and coupled to an external magnet placed on the skin, which facilitated stomach and abdominal wall apposition for blind percutaneous gastrostomy tube placement. Then, a gastrostomy tube was percutaneously and blindly placed. RESULTS: Twelve procedures were undertaken in animal cadavers and two in live models. The technique chosen consisted of using a magnetic gastric tube prototype using six 1 × 1-cm-ring magnets attached to its end. This device enabled successful magnetic coupling with a large (5 cm in diameter) magnet disc placed on the skin. For gastric tube placement, a direct trocar insertion allowed easier and safer placement of a gastric tube as compared to a needle-guide-wire dilation (Seldinger-based) technique. Gastropexy was added to avoid early gastric tube displacement. This novel PMG technique was feasible in a live model experiment. CONCLUSIONS: A novel magnetically guided percutaneous gastrostomy tube insertion technique without the use of endoscopy or image-guidance was successful in a porcine model. A non-inferiority experimental controlled study comparing this technique to percutaneous endoscopic gastrostomy is needed to confirm its efficacy and safety.

A prototype single-port device for pressurized intraperitoneal aerosol chemotherapy. Technical feasibility and local drug distribution.

PURPOSE: To evaluate the technical feasibility and homogeneity of drug distribution of pressurized intraperitoneal aerosol chemotherapy (PIPAC) based on a novel process of intraperitoneal drug application (multidirectional aerosolization). METHODS: This was an in vivo experimental study in pigs. A single-port device was manufactured at the smallest diameter possible for multidirectional aerosolization of the chemotherapeutic drug under positive intraperitoneal pressure. Four domestic pigs were used in the study, one control animal that received multidirectional microjets of 9 mL/sec for 30 min and three animals that received multidirectional aerosolization (pig 02: 9 mL/sec for 30 min; pigs 03 and 04: 3 mL/sec for 15 min). Aerosolized silver nitrate solution was applied for anatomopathological evaluation of intraperitoneal drug distribution. RESULTS: Injection time was able to maintain the pneumoperitoneum pressure below 20 mmHg. The rate of moderate silver nitrate staining was 45.4% for pig 01, 36.3% for pig 02, 36.3% for pig 03, and 72.7% for pig 04. CONCLUSIONS: Intra-abdominal drug distribution had a broad pattern, especially in animals exposed to the drug for 30 min. Our sample of only four animals was not large enough to demonstrate an association between aerosolization and a higher silver nitrate concentration in the stained abdominal regions.

Effectiveness of a reusable low-cost balloon trocar dissection device in the creation of preperitoneal space during endoscopic surgery. An experimental study in swine.

PURPOSE: To evaluate a new, low-cost, reusable balloon trocar device for dissection of the preperitoneal space during endoscopic surgery. METHODS: Twenty swine (weight: 15-37 kg) were randomized to two groups, according to whether the preperitoneal space was created with a new balloon device manufactured by Bhio-Supply (group B) or with the commercially available OMSPDB 1000® balloon device manufactured by Covidien (group C). Quality and size of the created preperitoneal space, identification of anatomic structures, balloon dissection time, total procedure time, balloon resistance and internal pressure after insufflation with 300 mL of ambient air, balloon-related complications, and procedure cost were assessed. RESULTS: No significant differences in dissection time, total procedure time, or size of the created preperitoneal space were found between the groups. Balloons in group B had a significantly higher internal pressure compared to balloons in group C. None of the balloons ruptured during the experiment. Three animals in group C had balloon-related peritoneal lacerations. Despite a higher individual device cost, group B had a lower procedure cost over the entire experiment. CONCLUSION: The new balloon device is not inferior to the commercially available device in terms of the safety and effectiveness for creating a preperitoneal space in swine.

A prototype single-port device for pressurized intraperitoneal aerosol chemotherapy. Technical feasibility and local drug distribution

Abstract Purpose: To evaluate the technical feasibility and homogeneity of drug distribution of pressurized intraperitoneal aerosol chemotherapy (PIPAC) based on a novel process of intraperitoneal drug application (multidirectional aerosolization). Methods: This was an in vivo experimental study in pigs. A single-port device was manufactured at the smallest diameter possible for multidirectional aerosolization of the chemotherapeutic drug under positive intraperitoneal pressure. Four domestic pigs were used in the study, one control animal that received multidirectional microjets of 9 mL/sec for 30 min and three animals that received multidirectional aerosolization (pig 02: 9 mL/sec for 30 min; pigs 03 and 04: 3 mL/sec for 15 min). Aerosolized silver nitrate solution was applied for anatomopathological evaluation of intraperitoneal drug distribution. Results: Injection time was able to maintain the pneumoperitoneum pressure below 20 mmHg. The rate of moderate silver nitrate staining was 45.4% for pig 01, 36.3% for pig 02, 36.3% for pig 03, and 72.7% for pig 04. Conclusions: Intra-abdominal drug distribution had a broad pattern, especially in animals exposed to the drug for 30 min. Our sample of only four animals was not large enough to demonstrate an association between aerosolization and a higher silver nitrate concentration in the stained abdominal regions.

Effectiveness of a reusable low-cost balloon trocar dissection device in the creation of preperitoneal space during endoscopic surgery. An experimental study in swine

PURPOSE: To evaluate a new, low-cost, reusable balloon trocar device for dissection of the preperitoneal space during endoscopic surgery.METHODS:Twenty swine (weight: 15-37 kg) were randomized to two groups, according to whether the preperitoneal space was created with a new balloon device manufactured by Bhio-Supply (group B) or with the commercially available OMSPDB 1000(r) balloon device manufactured by Covidien (group C). Quality and size of the created preperitoneal space, identification of anatomic structures, balloon dissection time, total procedure time, balloon resistance and internal pressure after insufflation with 300 mL of ambient air, balloon-related complications, and procedure cost were assessed.RESULTS:No significant differences in dissection time, total procedure time, or size of the created preperitoneal space were found between the groups. Balloons in group B had a significantly higher internal pressure compared to balloons in group C. None of the balloons ruptured during the experiment. Three animals in group C had balloon-related peritoneal lacerations. Despite a higher individual device cost, group B had a lower procedure cost over the entire experiment.CONCLUSION:The new balloon device is not inferior to the commercially available device in terms of the safety and effectiveness for creating a preperitoneal space in swine.