Search PubMed⌕ Search

Biomedical subjects

M Stamos

Publications and source records attributed to M Stamos.

6 recordsLinked to original sources

Does sodium hyaluronate- and carboxymethylcellulose-based bioresorbable membrane (Seprafilm) decrease operative time for loop ileostomy closure?

BACKGROUND: Adhesions can result in serious clinical complications and make ileostomy closure, which is relatively simple procedure into a complicated and prolonged one. The use of sodium hyaluronate and carboxymethyl cellulose membrane (Seprafilm) was proven to significantly reduce the postoperative adhesions at the site of application. The aim of this study was to assess the incidence and severity of adhesions around a loop ileostomy and to analyze the length of time and morbidity for mobilization at the time of ileostomy closure with and without the use of Seprafilm. METHODS: Twenty-nine surgeons from 15 institutions participated in this multicenter prospective randomized study. 191 patients with loop ileostomy construction were randomly assigned to either receive Seprafilm under the midline incision and around the stoma (Group I), only under the midline incision (Group II), or not to receive Seprafilm (Group III). At ileostomy closure, adhesions were quantified and graded; operative morbidity was also measured. RESULTS: All 3 groups were comparable relative to gender, mean age and number of patients with prior operations (26, 25 and 19, respectively). Group II patients were significantly more likely to have pre-existing adhesions than Group III patients (30.6% vs. 14.1%, p = 0.025). At stoma mobilization, significantly more patients in Group III than in Group I had adhesions around the stoma (95.2% vs. 82.3%, p = 0.021). Mean operative times were 27, 25, and 28 minutes, respectively (p = 0.38), with significant differences among sites. There was no significant difference in the number of patients needing myotomy or enterotomy (29, 27 and 24 patients, respectively), nor in the number of postoperative complications (7, 9 and 7 patients, respectively). CONCLUSIONS: When consistently applied, Seprafilm significantly decreased adhesion formation around the stoma but not operative times without any increase in the need for myotomy or enterotomy. These findings were not seen in the overall study population possibly due to the large number of surgeons using a variety of application techniques.

Adjuvants, Immunologic↗

Keratinocyte growth factor promotes healing of left-sided colon anastomoses.

BACKGROUND: Inadequate healing and consequent leakage from bowel anastomoses are a significant cause of postoperative morbidity and mortality. Systemic application of keratinocyte growth factor (KGF) has been shown to promote mucosal healing in models of colitis in rats and mice. The aim of the present study was to evaluate the effect of systemic KGF administration on healing of colonic anastomoses in rats. METHODS: Rats underwent laparotomy, division of the left colon, and sigmoido-sigmoidostomy. KGF (5 mg/kg) or vehicle were administered intraperitoneally in two groups (n = 30 per group) 12 hours prior to surgery, and then once daily until sacrifice (6 animals per group; 2, 4, 7, 12, and 21 days after surgery). Bursting pressure measurements, histologic evaluation, morphometric analysis, mucin and collagen staining, and hydroxyproline measurements of the anastomotic site were performed. RESULTS: Administration of KGF significantly increased anastomotic bursting pressure on postoperative days 2, 4, and 7 by 34%, 49%, and 19%, respectively. Histology, mucin staining, and measurements of the colonic crypt depth showed markedly less extended inflammation with an increased acidic mucin content and a significantly thickened mucosal layer in the KGF treated group when compared with vehicle-treated animals. CONCLUSIONS: KGF promotes healing of colonic anastomoses in rats during a 1-week postoperative period following large bowel surgery. KGF may be acting to accelerate host reparative processes as well as to enhance protection of the anastomotic wound bed by increased colonic epithelium proliferation, increased mucus production, and reduction of the inflammatory activity at the anastomotic site.

Anastomosis, Surgical↗

Use of intraperitoneal 5-fluorouracil and chlorhexidine for prevention of recurrence of perforated colorectal carcinoma in a rat model.

PURPOSE: Colorectal cancer is a prevalent and mortal disease, resulting in nearly 55,000 deaths in the United States annually. Preoperative or intraoperative spillage of tumor cells because of perforation occurs in up to 10 percent of cases. When this spillage occurs, the chance of recurrence and death is dramatically increased. METHODS: In an effort to reduce the chance of recurrence and death, we used a rat model to evaluate the efficacies of intraperitoneal 5-fluorouracil and chlorhexidine in reducing the incidence of recurrence. Rats were injected with 10 mg/kg azoxymethane subcutaneously weekly for 12 weeks to induce colorectal cancers. At 20 weeks, subtotal colectomies were performed on rats with colorectal tumors and without peritoneal implants or liver metastases. At the time of surgery, a cut portion of the tumor was placed in the abdomen for 30 minutes; the rats then randomly received peritoneal irrigation with 5-fluorouracil, chlorhexidine, or sterile water (control). Eight weeks postoperatively a necropsy was performed. At that time, obvious and suspected recurrences and the anastomotic area were sampled for histologic evaluation. RESULTS: Significant differences were seen with chlorhexidine vs. water for gross tumor (P = 0.05) and microscopic tumor (P < 0.05). 5-Fluorouracil showed a greater rate of abscess formation vs. both control and chlorhexidine (P > 0.05). CONCLUSIONS: Use of chlorhexidine intraperitoneal therapy at the time of the operation for perforated colorectal cancer significantly decreases the frequency of gross tumor recurrence but not total recurrences. Intraperitoneal 5-fluorouracil does not significantly decrease recurrence and may increase the risk of abscess when used intraoperatively.

Animals↗

The role of barium enema in colostomy closure in trauma patients.

Recently, the routine use of barium enema preceding colostomy closure in trauma patients has been challenged. It has been argued that the nature of the injury should be apparent from the initial laparotomy and that the likelihood of finding an unsuspected colonic lesion in the young, previously healthy patients who constitute the majority of trauma patients is very small. We retrospectively reviewed 124 consecutive cases of patients who received colostomy takedowns for trauma. One hundred six of the patients had preoperative barium enema evaluation. 87.1 per cent of the examinations were negative, with a subsequent stoma closure complication rate of 20.4 per cent. Of the 13 positive barium enemas, 9 were falsely positive. These patients had a higher stoma closure complication rate of 39 per cent, a fact that could not be explained on the basis of their abnormal studies. The 18 patients who did not have barium enema performed did not have an increase in complications (17.6%). Barium enema failed to uncover unsuspected pertinent diagnoses, often added unnecessary delays and expense, and in no case changed the operative management. Contrast studies were found to be useful in defining anatomy in cases of known fistulas and when the takedowns were performed without the benefit of operative reports from the previous surgery.

Adolescent↗

A forty-year experience with anal carcinoma: changing trends and impact of multimodality therapy.

Anal canal carcinoma is a rare clinical entity accounting for 1 to 3 per cent of all gastrointestinal malignancies. Abdominoperineal resection used to be the primary modality of treatment. However, recurrence rates of 20 to 40 per cent were observed after this mutilating procedure. In recent years, multimodality therapy with radiation and chemotherapy has shown at least equal results with the intention to preserve sphincter function. The objective of this study is to describe our experience at Harbor-UCLA Medical Center during the past 4 decades (1955-95), emphasizing changes in demographics, clinical presentation, and impact of multimodality therapy. Seventy-eight patients with the diagnosis of anal canal carcinoma were included. A steady increase in the incidence of anal carcinoma in younger people was observed (24% less than 64 years old for the 1955-65 period versus 75% for 1986-95 period). A female predominance was found in 1955-65 period, with F:M ratio 1.5, and a majority of male cases was seen in the last period (1986-95). Abdominoperineal resection was the preferred treatment during 1955-65, whereas during 1986-95 chemoradiation was the treatment of choice. We observed a trend from primary surgical treatment toward chemoradiotherapy with improvement in survival and preservation of ano-rectal function. Since 1988, we have not performed an abdominoperineal resection for primary treatment of anal carcinoma. Survival analysis was made grouping the patient population according to primary treatment. Higher survival rates were observed in the groups that received chemoradiotherapy (P = 0.0368) either as adjuvant or primary therapy. Chemoradiotherapy should be recommended as primary therapy to most patients.

Abdomen↗

Rectal carcinoma: are we making a difference?

Evaluation of preliminary results at our institution revealed an improvement in survival of patients treated for rectal cancer from 1950-1988. A study was conducted to analyze responsible factors. A total of 335 patients with accurate staging and follow up for at least 5 years or until death were reviewed retrospectively. Of the 335 patients, 295 (88%) were treated by surgical resection, abdominal perineal resection (APR) (n=179), and anterior resections (n=105), the most common procedures. Operative mortality for patients with curable disease (n=188) was 18 per cent (n=34), which has significantly decreased from 24 per cent (n=28) (1950-1969) to 8 per cent (n=6) (1970-1988), (P < 0.01). Operative mortality for APR and anterior resection was 22 per cent (n=29) and 8 per cent (n=5), respectively. Mortality for APR decreased from 28 per cent (1950-1969) to 10 per cent (1970-1988) (P < 0.02) accounting for most of the improvement. Of the 335 patients, 142 (42%) presented with stage IV disease, which decreased from 54 per cent (n=47) (1950s) to 22 per cent (n=10) (1980s), P < 0.01. The overall 5-year survival was 19 per cent (n=64), with a corresponding increase per decade from 13 per cent (1950s) to 43 per cent (1980s), (P < 0.001). Of the remaining 188 patients, 41 had involved surgical margins and decreased 5-year survival of 8 per cent when compared to patients with clear surgical margins (37%) P < 0.01). Multifactor analysis revealed that stage of disease at presentation, involved surgical margins, and operative mortality were significant independent variables. Earlier stage at presentation and improved operative management increased the survival of patients with rectal cancer at our institution.

Cause of Death↗