Loop-anchor purse-string closure of gastrotomy in NOTES(R) procedures: survival studies in a porcine model.

INTRODUCTION: Transgastric NOTES(®) procedures remain without a simple method to close the gastrotomy. In four survival swine studies, we have tested a novel gastric closure device: the loop-anchor purse-string (LAPS) closure system. METHODS: In four anesthetized pigs, an endoscopic gastrotomy was performed. Four loop anchors were arrayed in a 2-cm square pattern around the gastrotomy. The endoscope was passed into the abdominal cavity, and the gastrotomy was cinched closed. RESULTS: Procedure times ranged from 50-180 minutes. Three pigs survived 14 days. One animal was sacrificed early due to signs of sepsis. Another animal developed fevers and was treated with antibiotics. At necropsy, there were no abscesses, including in the septic animal. Histologic examination revealed evidence of healing in all animals. DISCUSSION: The LAPS system holds promise with early success in an animal model. Future human studies are needed to determine viability as a human visceral closure device.

Pain and the defense response: structural equation modeling reveals a coordinated psychophysiological response to increasing painful stimulation.

The defense response theory implies that individuals should respond to increasing levels of painful stimulation with correlated increases in affectively mediated psychophysiological responses. This paper employs structural equation modeling to infer the latent processes responsible for correlated growth in the pain report, evoked potential amplitudes, pupil dilation, and skin conductance of 92 normal volunteers who experienced 144 trials of three levels of increasingly painful electrical stimulation. The analysis assumed a two-level model of latent growth as a function of stimulus level. The first level of analysis formulated a nonlinear growth model for each response measure, and allowed intercorrelations among the parameters of these models across individuals. The second level of analysis posited latent process factors to account for these intercorrelations. The best-fitting parsimonious model suggests that two latent processes account for the correlations. One of these latent factors, the activation threshold, determines the initial threshold response, while the other, the response gradient, indicates the magnitude of the coherent increase in response with stimulus level. Collectively, these two second-order factors define the defense response, a broad construct comprising both subjective pain evaluation and physiological mechanisms.

From critical values to critical diagnoses: a review with an emphasis on cytopathology.

The concept of critical values in the medical laboratory found its roots in clinical pathology nearly 40 years ago. The goal of this review was to trace the evolution of the critical value concept from clinical into anatomic pathology with specific emphasis on cytopathology. Difficulties in the meaningful application of the critical value concept in the practice of cytopathology are reviewed along with ambiguities that have yet to be fully resolved. Suggestions that may enhance the operational success of critical value policies in cytopathology and a central role for the cytotechnologist are presented. Cooperation between key pathology and clinical organizations is essential for improvement in the critical value process.

Gastrotomy closure with the lock-it system and the Padlock-G clip: a survival study in a porcine model.

BACKGROUND AND STUDY AIMS: The success of natural orifice surgery depends on secure closure of the transmural gut opening, so a rapid, secure, and easy-to-place closure method is desirable. Our aim was to determine whether a gastrotomy can be closed safely and effectively from within the stomach in a survival model by using a novel, endoscopically placed device: the Padlock-G system. PATIENTS AND METHODS: This was a pilot study of 4 survival animals in an animal laboratory setting. Gastrotomies were made in the stomachs of laboratory swine, and the abdomen was explored by using a standard gastroscope. Gastrotomies were then closed by using the Padlock-G system. Survival for 2 or 6 weeks was the primary outcome measurement. Secondary outcomes included ease of use, visual assessment of closure integrity immediately and at necropsy, presence of adhesions, evidence of infection, and histologic appearance at the closure sites. RESULTS: All animals thrived, ate normally, and gained weight. None developed fever, tachycardia, or signs of peritoneal irritation. Closure-site inspection at necropsy revealed excellent healing, with epithelial growth over the Padlock-G. There were no ulcers, serosal surfaces were tightly closed, and no defects could be seen. There were no signs of peritoneal inflammation, intra-abdominal adhesions, or gastric spillage. Histologic evaluation showed organizing granulation tissue with fibrosis, vascular proliferation, and mild chronic inflammatory infiltrate (i.e., scar). CONCLUSIONS: The Padlock-G is easy to place, provides a durable closure, and allows survival animals to thrive without adverse sequellae. This device provides a suitable closure system for transgastric NOTES.