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Query: UMLS:C0021843 (bowel obstruction)
 9,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This article summarizes the discussions of the faculty and chairpersons on four major topics on postsurgical adhesions examined at the symposium, "Adhesions: Pathogenesis and Prevention". These topics are: 1) clinical significance; 2) pathogenesis; 3) research status and directions; and 4) recommendations for reduction or prevention. Abdominal postsurgical adhesions develop following trauma to the mesothelium, which is damaged often by surgical handling and instrument contact, foreign materials such as sutures and glove dusting powder, desiccation, and overheating. Postoperative adhesions occur after most surgical procedures and can result in serious complications, including intestinal obstruction, infertility, and pain. A long-term and unpredictable problem, postoperative adhesions impact the surgical workload and hospital resources, resulting in considerable health care expenditures. Although understanding of the pathogenesis of adhesions has improved recently, the molecular mechanisms involved continue to be delineated. Adhesions result from the normal peritoneal wound healing response and develop in the first five to seven days after injury. Adhesion formation and adhesion-free re-epithelialization are alternative pathways, both of which begin with coagulation which initiates a cascade of events resulting in the buildup of fibrin gel matrix. If not removed, the fibrin gel matrix serves as the progenitor to adhesions by forming a band or bridge when two peritoneal surfaces coated with it are apposed. The band or bridge becomes the basis for the organization of an adhesion. Protective fibrinolytic enzyme systems of the peritoneum, such as the plasmin system, can remove the fibrin gel matrix. However, surgery dramatically diminishes fibrinolytic activity. The pivotal events determining whether the pathway taken is adhesion formation or re-epithelialization are therefore the apposition of two damaged surfaces and the extent of fibrinolysis. Research in postsurgical adhesion formation and prevention abounds in a variety of avenues of investigation, including: 1) identification on a molecular level of the components involved in adhesiogenesis and their interactions; 2) clarification of the role of fibrin and fibrinolysis in adhesion formation; 3) standardization of design in preclinical and clinical studies of adhesion formation and prevention; 4) delineation of the relationship between adhesion formation and adhesive complications; and 5) elucidation of efficient, site-specific methods of prophylactic drug delivery. Currently, it seems logical to focus preventive research on development of barriers, fibrinolytic drugs, and selected agents such as phospholipids. The major strategies for adhesion prevention or reduction are adjusting surgical practice and applying adjuvants. Surgeons should adjust their major practices by: 1) becoming aware of the potential adhesive complications of a procedure; 2) minimizing the invasiveness of surgery; and 3) minimizing surgical trauma, ischemia, exposure to intestinal contents, introduction of foreign material into the body, and the use of talc- or starch-containing gloves. Available adjuvants include a newly developed by hyaluronic acid-phosphate-buffered saline solution applied intraoperatively to protect peritoneal surfaces from indirect surgical trauma and three mechanical barriers. One of these, a bioresorbable membrane consisting of hyaluronic acid and carboxymethylcellulose, has demonstrated efficacy and safety in both general and gynecological surgery. The other two barriers, one made of expanded polytetrafluoroethylene and one developed from oxidized regenerated cellulose, are indicated only for use in gynecological surgery.
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PMID:Adhesions: pathogenesis and prevention-panel discussion and summary. 907 53

The development of postoperative adhesions remains an almost inevitable consequence of visceral and gynecological surgery, appearing in 50-95% of all patients. The pathogenetical sequence from peritoneal injury, with locally released cytokines and inflammatory reaction, to permanent fibrous adhesions has been elucidated in recent years. Early and late bowel obstruction, chronic abdominal pain, and infertility are the main clinical complications, and they also increase the socio-economic costs. Laparoscopic surgical procedures with their minimal access to the abdominal cavity are associated with fewer postoperative adhesions compared to open surgery, although adhesion formations cannot be entirely prevented.
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PMID:Comparison of adhesion formation in open and laparoscopic surgery. 984 78

Intra-abdominal adhesions are fibrotic structures, which lie in the form of a string or attachment between the abdominal organs and connect these together. They are responsible for serious clinical complications that include intestinal obstruction, infertility, and pelvic pain. During the last century, surgeons' comprehensive understanding of the biology of peritoneal healing and wound repair has allowed them to identify a variety of new therapeutic techniques that limit the development of adhesion formation. New drugs, dextran 70 and poloxamer 407, have been developed to prevent adhesion formation. In addition, three new biomaterials (oxidized regenerated cellulose, hyaluronate membrane, and polytetrafluoroethylene) are synthetic barriers being used to prevent adhesions.
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PMID:Peritoneal healing with adhesion formation: current comment. 1017 69

The most common cause of intraperitoneal adhesions which may result in infertility and intestinal obstruction is previous abdominal surgery. Surgical trauma of the peritoneum in the absence of infection elicits a rapid and transient influx of polymorphonuclear leukocytes (PMN) into the peritoneal cavity. The role of neutrophils in intraperitoneal adhesion formation has not been studied. We aimed to study the effects of PMN counts and PMN functions on peritoneal adhesion formation. Forty peritoneal adhesion-induced rats were randomly divided into three groups; group I, receiving saline; group II, receiving cyclophosphamide; and group III, receiving granulocyte-macrophage colony-stimulating factor (GM-CSF). In all groups, peritoneal lavage was performed to determine PMN counts the day after adhesion induction. Blood neutrophil counts and neutrophil functions were also determined. Adhesions were evaluated blindly 14 days after the operation. Adhesion tissue samples were microscopically evaluated. Tissue hydroxyproline and collagen concentrations were measured. The neutrophil counts and phagocytosis significantly increased in group III and neutrophil counts decreased in group II (P < 0.05). The score of adhesion formation in group II was significantly less than that in groups I and III (P < 0.05). Hydroxyproline concentrations of adhesion tissue were significantly decreased in group II when compared with group III (P < 0.05). The present study shows that neutropenia lowers the degree of postoperative adhesion formation. It is concluded that PMN may have a role to play in modulating post-operative adhesion formation.
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PMID:The role of neutrophils in the formation of peritoneal adhesions. 1037 93

Cystic fibrosis (CF) is a lethal autosomal recessive genetic disease caused by mutations in the CF transmembrane conductance regulator (CFTR). Mutations in the CFTR gene may result in a defective processing of its protein and alter the function and regulation of this channel. Mutations are associated with different symptoms, including pancreatic insufficiency, bile duct obstruction, infertility in males, high sweat Cl-, intestinal obstruction, nasal polyp formation, chronic sinusitis, mucus dehydration, and chronic Pseudomonas aeruginosa and Staphylococcus aureus lung infection, responsible for 90% of the mortality of CF patients. The gene responsible for the cellular defect in CF was cloned in 1989 and its protein product CFTR is activated by an increase of intracellular cAMP. The CFTR contains two membrane domains, each with six transmembrane domain segments, two nucleotide-binding domains (NBDs), and a cytoplasmic domain. In this review we discuss the studies that have correlated the role of each CFTR domain in the protein function as a chloride channel and as a regulator of the outwardly rectifying Cl- channels (ORCCs).
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PMID:Structure and function of the cystic fibrosis transmembrane conductance regulator. 1045 65

Perforation of the uterus by an intrauterine contraceptive device (IUD) is a rare, and serious complication, occurring in 1/350 to 1/2500 insertions. Perforation by IUDs can involve several neighboring organs such as the bladder and rectosigmoid. We report two cases of IUD perforations involving the appendix, both inserted during lactation. The first case is an asymptomatic patient in early pregnancy and the second is a woman whose original presentation was chronic lower abdominal pain. The presence of copper in the abdominal cavity can lead to adhesion formation and subsequent abdominal pain, bowel obstruction or infertility. Thus, we believe that when an IUD is located in the abdominal cavity it should be removed even in an asymptomatic patient. In addition, these cases might suggest postponing the use of this contraceptive method in lactating women.
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PMID:Appendix perforation by an intrauterine contraceptive device. 1069 Jun 69

For more than a century peritoneal adhesions are being recognized as frequent sequelae following abdominal surgery. Intraoperative lesions of the mesothelial lining by abrasion, ischemia, dissication, and foreign bodies result in complaints, intestinal obstruction, female infertility, and problems during reoperations. The global increase of life expectancy and surgical procedures are leading to rising incidences of adhesion-related complications and subsequent socio-economic implications. As of today, there is no safe and efficient prophylaxis available. Scientific efforts should be aimed at a liquid substance for single intraperitoneal application which significantly reduces postoperative adhesions at reasonable cost without adverse effects on blood coagulation and wound healing.
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PMID:[Prevention of adhesions. Wish and reality]. 1087 6

Peritoneal adhesions are a major complication of healing following surgery or infection and can lead to conditions such as intestinal obstruction, infertility, and chronic pain. Mature adhesions are the result of aberrant peritoneal healing and historically have been thought to consist of non-functional scar tissue. The aim of the present study was to analyse the cellular composition, vascularity, and extracellular matrix distribution of human peritoneal adhesions, to determine whether adhesions represent redundant scar tissue or are dynamic regenerating structures. Furthermore, the histological appearance of each adhesion was correlated with the clinical history of the patient, to determine whether maturity or intraperitoneal pathology influences adhesion structure. Human peritoneal adhesions were collected from 29 patients undergoing laparotomy for various conditions and were prepared for histology, immunocytochemistry, and transmission electron microscopy. All adhesions were highly vascularized, containing well-developed arterioles, venules, and capillaries. Nerve fibres, with both myelinated and non-myelinated axons, were present in adhesions from nearly two-thirds of the patients, with increased incidence in those with a malignancy. Approximately one-third of the adhesions contained conspicuous smooth muscle cell clusters lined by collagen fibres of heterogeneous size. Adipose tissue was a consistent feature of all the adhesions, with some areas displaying fibrosis. There appeared to be no correlation between the estimated maturity or site of each adhesion and its histological appearance. However, intraperitoneal pathology at the time of surgery did influence the incidence of some histological features, such as the presence of nerve fibres, clusters of smooth muscle cells, and inflammation. This study challenges previous concepts that adhesions represent non-functional scar tissue and clearly demonstrates that established adhesions are highly cellular, vascularized, and innervated, features more consistent with dynamic, regenerating structures.
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PMID:Human peritoneal adhesions are highly cellular, innervated, and vascularized. 1095 2

Adhesions in the peritoneal cavity have been implicated in the cause of intestinal obstruction and infertility, but their role in the aetiology of chronic pelvic pain is unclear. Nerves have been demonstrated in human pelvic adhesions, but the presence of pain-conducting fibres has not been established. The purpose of this study was to use an animal model to examine the growth of nerves during adhesion formation at various times following injury and to characterize the types of fibres present. Adhesions were generated in mice by injuring the surface of the caecum and adjacent abdominal wall, with apposition. At 1-8 weeks post-surgery, adhesions were processed and nerve fibres characterized histologically, immunohistochemically, and ultrastructurally. Peritoneal adhesions had consistently formed by 1 week after surgery and from 2 weeks onwards, all adhesions contained some nerve fibres which were synaptophysin, calcitonin gene-related peptide, and substance P-immunoreactive, and were seen to originate from the caecum. By 4 weeks post-surgery, nerve fibres were found to originate from both the caecum and the abdominal wall, and as demonstrated by acetylcholinesterase histochemistry, many traversed the entire adhesion. Ultrastructural analysis showed both myelinated and non-myelinated nerve fibres within the adhesion. This study provides the first direct evidence for the growth of sensory nerve fibres within abdominal visceral adhesions in a murine model and suggests that there may be nerve fibres involved in the conduction of pain stimuli.
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PMID:Growth of nerve fibres into murine peritoneal adhesions. 1105 24

Postsurgical intra-abdominal adhesions pose a significant medical problem in the Western world, and in the past decade progress has been made in understanding their pathophysiology. The early balance between fibrin formation and degradation in the peritoneal cavity during and after surgery seems to be a major determinant of adhesion formation. Postsurgical inhibition of fibrinolytic activity severely impairs fibrin breakdown. Adhesive small-bowel obstruction, inadvertent enterotomy at reoperation, prolonged operative time dividing adhesions, increased clinical workload and high financial costs are important adhesion-related problems discussed in this review. The cumulative risk of adhesive small-bowel obstruction after (sub)total colectomy is 11% within 1 year, increasing to 30% at 10 years. One of five patients undergoing reoperation suffers from inadvertent enterotomy, resulting in significant postoperative morbidity and mortality. Roughly 3% of all surgical admissions are associated with intra-abdominal adhesions. Clinical prospective trials have recently been designed to investigate the efficacy of barrier membranes and gels in the reduction of abdominal and pelvic adhesions and prevention of long-term morbidity, e.g., adhesive bowel obstruction and infertility in women. Early results are promising and contribute to the increased interest among clinicians in postsurgical adhesion formation and its consequences.
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PMID:Recent clinical developments in pathophysiology, epidemiology, diagnosis and treatment of intra-abdominal adhesions. 1123 93


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