Biomedical subjects

Paul Swain

Publications and source records attributed to Paul Swain.

9 recordsLinked to original sources

PubMed2005

Future therapeutic indications for endoscopic ultrasound.

Attempts to perform therapy guided by endoscopic ultrasound (EUS) are rare. Some new indications for interventional and therapeutic endoscopic procedures performed under EUS control have been developed in areas that have been purely surgical for many years. Indications, procedures, and related tools for EUS-guided endosurgery are described, all of which are experimental but may open a new corridor for endoscopists to enter a variety of transluminal procedures in real time without soiling the peritoneal or mediastinal cavity.

Endosonography↗

PubMed2005

Experimental studies of transgastric gallbladder surgery: cholecystectomy and cholecystogastric anastomosis (videos).

BACKGROUND: Transgastric flexible endoscopic surgery might offer advantages over open and laparoscopic surgery. The aim of this study was to develop methods for performing transgastric biliary endosurgery. METHODS: Cholecystectomies and biliary anastomoses were performed in 8 anesthetized pigs (27-30 kg) in nonsurvival studies. Two endoscopes passed perorally were inserted through the stomach wall after needle-knife incision. Endoscope-induced pneumoperitoneum allowed viewing and manipulation of the gallbladder with both endoscopes independently. The cystic duct was dissected, clipped, and transected. Cholecystectomy was performed with one of two methods: either by using two endoscopes, or a single endoscope and a 5-mm-diameter grasping instrument inserted transabdominally. Clips and sutures were used to attach the gallbladder to the stomach wall, and an incision was made to form a cholecystogastrostomy. In survival experiments in 8 pigs, transgastric incisions were closed with endoscopic sutures. RESULTS: The gallbladder was successfully removed in 8 pigs (nonsurvival experiments). The time for the procedure ranged from 2.5 hours to 40 minutes and decreased with experience. At postmortem examination, clips placed on the cystic duct and the artery were secure. An anastomosis was successfully formed between gallbladder and stomach in 3 pigs. In 8 pigs, full-thickness incisions in the stomach wall were closed with two to 4 stitches. All 8 pigs survived (median follow-up, 22 days; range 14-28 days). CONCLUSIONS: Transgastric gallbladder surgery, including cholecystectomy and biliary anastomosis, is feasible. Full-thickness gastric incisions were safely closed in survival studies. The efficacy and the safety of transgastric surgery merits further study.

Anastomosis, Surgical↗

PubMed2004

Transgastric gastropexy and hiatal hernia repair for GERD under EUS control: a porcine model.

BACKGROUND: Endoluminal operations for gastroesophageal reflux currently are limited by the inability to visualize and manipulate structures outside the wall of the gut. This may be possible by using EUS. The aims of this study were the following: to define the EUS anatomy of structures outside the gut that influence reflux, to place stitches in the median arcuate ligament, to perform posterior gastropexy, and to test the feasibility of crural repair under EUS control in pigs. METHODS: In survival experiments in 22 pigs, by using a linear-array echoendoscope, the median arcuate ligament and part of the right crus were identified and punctured with a needle, which served as a carrier for a tag and thread. These were anchored into the muscle. An endoscopic sewing device was used, allowing stitches to be placed through a 2.8-mm accessory channel to any predetermined depth. New methods allowed knot tying and thread cutting through the 2.8-mm channel of the echoendoscope. RESULTS: Stitches were placed through the gastric wall into the median arcuate ligament, and one stitch was placed just beyond the wall of the lower esophageal sphincter. The stitches were tied together and locked against the gastric wall. Median lower esophageal sphincter pressure, determined manometrically, was 11 mm Hg before surgery and 21 mm Hg after stitch placement (p=0.0002). The length of the lower esophageal sphincter increased from a median of 2.8 cm before the procedure to 3.5 cm after the procedure. At the postmortem, the median force required to pull the tags out of the median arcuate ligament was 2.8 kg. CONCLUSIONS: This study demonstrates that transgastric gastroesophageal reflux surgery, by using stitching under EUS control, can significantly increase lower esophageal sphincter pressure in pigs.

Animals↗

PubMed2004

Endoscopic suturing.

We describe the development of endoscopic sewing machines and ancillary equipment for knot tying and thread cutting. We outline the experimental studies in dogs, pigs and baboons prior to the first studies in man. We consider the early results achieved by groups in Europe and the U.S.A., and present the available evidence from peer-reviewed studies and data from numerous abstracts on the use of endoscopic suturing in man for treating gastro-oesophageal reflux. We consider the limitations of the available studies, and outline the requirements for improvements in flexible endoscopic suturing methods.

Animals↗

PubMed2003

Bard EndoCinch: the device, the technique, and pre-clinical studies.

There is, of course, room for improvement. More work is needed to make endoscopic suturing easier, quicker and more reliable. The single most important next goal is to construct a device, which can place multiple stitches without the need to remove the endoscope between each stitch. Devices, which can place two stitches in one go, would be a start. The development of double stitch and multiple stitch devices has been described earlier. The authors are pleased to see two alternative commercial endoscopic sewing devices appear at the last DDW which place two stitches without needing to withdraw the endoscopes--they use a double needle method.

Anastomosis, Surgical↗

PubMed2003

Critical care transesophageal endosonography and guided fine-needle aspiration for diagnosis and management of posterior mediastinitis.

BACKGROUND: Acute mediastinitis is a serious complication; it occurs after esophageal perforation and thoracic surgery and is rarely due to infections. Clinical and computed tomographic scan signs may be nonspecific, especially in postoperative patients. DESIGN: We prospectively evaluated the value of transesophageal endosonography with guided fine-needle aspiration in the diagnosis and identification of etiologic agents in critically ill patients with suspected posterior mediastinitis. SETTING: University hospital. PATIENTS AND METHODS: Transesophageal endosonography/fine-needle aspiration was performed at the bedside in the intensive care unit with a Pentax 34UX echo-endoscope and a portable Hitachi console (EUB 525). Eighteen patients with clinically suspected mediastinitis were examined with intensive care team support. RESULTS: Computed tomography was performed before transesophageal endosonography in all 18 patients and was inconclusive in 9. Transesophageal endosonography detected mediastinal lesions in 16 (89%) of 18 patients and was more accurately diagnostic than computed tomography (p =.0082). Fifteen patients had undergone surgery (11 esophagectomy, 1 other esophageal surgery, 1 head/neck cancer surgery, 1 complication after dilatational tracheostomy, and 1 with intervention after polytrauma). Three patients were suspected to have nonpostoperative mediastinitis. In 16 patients, infectious organisms were detected (bacterial, n = 14; fungal, n = 1; tuberculosis, n = 1). Culture and sensitivity of transesophageal endosonography/fine-needle aspiration specimens led to appropriate drug therapy. In two patients, methicillin-resistant Staphylococcus aureus was detected, leading to isolation care. Twelve patients improved; six died. Of the two patients in whom transesophageal endosonography did not detect a mediastinitis, one was false negative on autopsy. There were no complications. CONCLUSION: Bedside transesophageal endosonography/fine-needle aspiration of posterior mediastinal lesions in critically ill patients was an effective and relatively noninvasive way to detect mediastinitis and provide material to identify the etiologic agent. It was particularly useful in postesophagectomy patients.

Abscess↗

PubMed2003

Endoscopic ultrasound-guided biopsy for the diagnosis of focal lesions of the spleen.

OBJECTIVES: Needle biopsy of splenic lesions using computed tomography (CT) or ultrasound (US) is difficult if the size of the lesion is small. It may be dangerous if the lesion is adjacent to the splenic hilum or located peripherally. We used endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) to elucidate the tissue diagnosis of splenic abnormalities. METHODS: EUS-FNA was performed in 12 patients when US- or CT-guided biopsy was inconclusive (n = 5), was not attempted because of small tumor size (0.9-1.4 cm; N = 4), or was considered dangerous (n = 3). A linear echo-endoscope and 22-gauge needles were used for cytology and bacteriology. RESULTS: The age of the patients was 19-68 yr (median 32 yr). Seven patients were male and five female. The size of the lesions was 0.8-4.2 cm (median 1.4 cm). Cytology was inadequate in one patient. Bacteriology was positive for Staphylococcus aureus and Serratia in one patient each, and cultures were positive for Mycobacterium tuberculosis in two patients. A positive diagnosis was made in 10 of 12 patients (83%). Final diagnoses were tuberculosis in two patients, Hodgkin's disease in two, sarcoidosis in two, abscesses in two, metastatic colon cancer in one, and infarction in one. Suspected recurrence of non-Hodgkin's lymphoma was not confirmed in one case. One patient experienced pain after puncture, but no hematoma was demonstrated on subsequent US examination. CONCLUSIONS: EUS-FNA cytodiagnosis in patients with unknown splenic lesions seems feasible, even in very small foci, when CT- or US-guided biopsy fails. Additional material for bacteriology may show benign treatable diseases such as abscesses or tuberculosis.

Adult↗

PubMed2002

Capsule endoscopy in the evaluation of patients with suspected small intestinal bleeding: Results of a pilot study.

BACKGROUND: A video capsule has been developed to acquire photographic images of the small intestine during normal peristaltic motion. METHODS: Patients between 21 and 80 years of age referred for enteroscopy because of obscure GI bleeding were offered entry into a trial in which they would undergo both capsule endoscopy and subsequent push enteroscopy. Results of capsule examinations were compared with push enteroscopy findings. Capsule endoscopy was performed with the Given M2A video capsule system. RESULTS: Twenty-one patients (12 women, 9 men, average age 61 years) were enrolled, all of whom completed the study. A bleeding site was found in 11 of 20 patients during capsule endoscopy. No additional intestinal diagnoses were made by enteroscopy. The yield of push enteroscopy in the evaluation of obscure bleeding was 30% (6/20), the yield of capsule endoscopy 55% (11/20). This difference did not reach statistical significance (p = 0.0625). Capsule endoscopy found a distal source of bleeding in 5 of 14 patients who had normal push enteroscopic examinations. Patients preferred capsule endoscopy to enteroscopy. CONCLUSIONS: This pilot study demonstrates that capsule endoscopy provides excellent visualization of the small intestine, is well tolerated by patients, and is safe. Capsule endoscopy identified small intestinal bleeding sites beyond the range of push enteroscopy.

Adult↗

PubMed2002

A through-the-scope device for suturing and tissue approximation under EUS control.

BACKGROUND: The ability to place sutures under EUS control might allow development of a new type of transluminal endosurgery. The aim of this study was to develop endoscopic methods for suturing to variable predetermined depths in the wall of the GI tract and to allow fixation of adjacent hollow organs under EUS control. METHODS: A suturing device was constructed for suturing under EUS control to any desired depth. Sutures can also be placed into hollow or solid organs within 5 cm of the endoscope tip. The device allows multiple sutures to be placed without withdrawing the endoscope. Stitching, knot-tying, and thread-cutting are achieved through a 2.8-mm accessory channel. RESULTS: Multiple (>100) sutures were placed in predetermined gut wall layers in pigs. Sutures were placed in the gallbladder (n = 7) and small intestine (n = 8) to fix the gallbladder/small intestine to the stomach and allow traction for the insertion of stents and other devices through the 2 lumens. CONCLUSION: A new method for stitching under flexible EUS control is described. This technology was used to place sutures at precise depths in the GI tract. It allowed fixation of other organs to the accessible GI tract for various purposes including delivery of stents and devices for creating anastomoses.

Animals↗