Biomedical subjects

Turner Osler

Publications and source records attributed to Turner Osler.

13 recordsLinked to original sources

PubMed2005

Localizing colorectal cancer by colonoscopy.

HYPOTHESIS: Colonoscopic localization of colorectal carcinoma is frequently inaccurate and unreliable. DESIGN: Consecutive case series. SETTING: Tertiary care teaching hospital. PATIENTS: Three hundred fourteen consecutive patients undergoing surgical resection for colorectal cancer from January 1, 2000, to December 31, 2003. INTERVENTION: Surgical resection for colorectal cancer. MAIN OUTCOME MEASURE: Incidence of erroneous site localization. RESULTS: Two hundred thirty-six patients had complete endoscopic, pathologic, and operative records. Colonoscopy was inaccurate for tumor localization in 49 cases (21%). In 27 (11%) of these cases, a different procedure was required than initially planned; in an additional 10 cases (4%), the surgical approach required modification. Inaccurate localization was associated with previous colorectal procedures on both univariate analysis (odds ratio, 3.94; 95% confidence interval, 1.50-10.32; P<.005) and multivariate analysis (odds ratio, 4.47; 95% confidence interval, 1.64-12.08; P = .003). Having the colonoscopy performed by a surgeon trended toward protection from error on multivariate analysis (odds ratio, 0.47; 95% confidence interval, 0.20-1.08; P = .07). Age, sex, diverticular disease, endoscopist volume and years of training, and bowel preparation had no significant effect. CONCLUSIONS: Colonoscopy has a considerable error rate for localization of colorectal cancer, especially when previous colorectal procedures have been performed. Adjunctive localizing techniques, such as endoscopic tattooing, should be strongly considered.

Adult↗

PubMed2005

Urgent subtotal colectomy for severe inflammatory bowel disease.

PURPOSE: The purpose of this study was to assess the safety of subtotal colectomy and outcomes after this procedure in the modern era of immunosuppressive agents and primary pelvic pouch surgery. METHODS: All patients undergoing subtotal colectomy with ileostomy for ulcerative colitis or Crohn's colitis from July 1, 1990 to June 30, 2003 were identified from a prospective database. Only patients who were operated on while hospitalized for disease exacerbation were included in the analysis. Age at colectomy, preoperative days in the hospital, postoperative length of stay, and complications were recorded. The medical records were then reviewed for duration of disease, preoperative diagnosis, use of steroids and immunomodulators, parenteral nutrition, endoscopy findings, albumin level, postoperative diagnosis, and ultimate disposition. RESULTS: One hundred one patients underwent subtotal colectomy for inflammatory bowel disease during the study period. Seventy-four patients met all the inclusion criteria. The mean age was 35.9 (range, 18-86) years. Median duration of disease was 36 (0-240) months, but 28 patients had colitis for less than 1 year, whereas 10 patients had disease of greater than 10 years duration at the time of colectomy. Median preoperative hospital stay was 7 (range, 0-43) days and median postoperative length of stay was 6.5 (range, 4-37) days. Sixty-six patients underwent surgery for refractory exacerbation, 5 for free perforation, 2 for abscess, and 1 patient for hemorrhage. Twenty-seven patients (36.5 percent) had a change in diagnosis after surgery. Complications occurred in 17 patients (23 percent), including 8 cases of central venous catheter-associated thrombosis; 7 of these occurred in patients who had been hospitalized for more than a week before surgery. In the ulcerative colitis patients, 31 of 52 ultimately underwent ileal pouch-anal anastomosis, but 20 (39 percent) chose either completion proctectomy or no further surgery. CONCLUSIONS: Subtotal colectomy with ileostomy remains a safe and effective treatment for patients requiring urgent surgery for severe inflammatory bowel disease. Because of the substantial incidence of change in diagnosis and satisfaction in many patients with an ileostomy, subtotal colectomy with ileostomy may be preferable to primary ileal pouch-anal anastomosis, even when a pouch is considered safe.

Adolescent↗

PubMed2005

Transanal endoscopic microsurgery: a prospective evaluation of functional results.

PURPOSE: Local excision is a commonly used technique for many benign and selected malignant rectal lesions. Compared with radical resection, it is associated with decreased morbidity and mortality and improved functional results. Transanal endoscopic microsurgery is gaining popularity because of its ability to access the upper rectum and its precise excision techniques. However, the functional consequences have not been extensively studied. METHODS: All patients subject to transanal endoscopic microsurgery prospectively completed preoperative and postoperative (6 weeks) surveys including Fecal Incontinence Severity Index, Fecal Incontinence Quality of Life, number of bowel movements per 24 hours, and ability to defer defecation. All data were collected by an independent research coordinator. Demographics, operative details, and complications were also collected prospectively. RESULTS: Forty-one patients successfully underwent transanal endoscopic microsurgery. Fourteen patients had malignant lesions and 27 had benign lesions. Two patients required abdominoperineal resection based on postoperative diagnosis. Thirty-nine patients have completed follow-up and were available for review. Mean length of surgery was 64 minutes and length of stay was 0.9 day. Average distance from the anal verge to the proximal tumor margin was 11.4 cm and mean tumor size was 8.75 cm. Twenty-three patients had full-thickness excision with primary closure, ten had full-thickness excision without closure, five had partial-thickness excision, one had an excision of a mass in the anovaginal septum, and one had resection of an anastomotic stricture. Each patient served as his own control. Preoperative and postoperative number of bowel movements per 24 hours were 2.0 and 2.0, respectively. Preoperative vs. postoperative urgency (ability to defer defecation less than ten minutes) was unchanged. Mean preoperative and postoperative Fecal Incontinence Severity Index scores were 2.4 (range, 0-43) and 2.4 (range, 0-17), respectively (higher scores indicate worse function). In addition, the four parameters measured by the Fecal Incontinence Quality of Life survey were unchanged when preoperative and postoperative data were compared. CONCLUSIONS: Transanal endoscopic microsurgery allows precise excision of tumors throughout the rectum. However, it involves inserting a 40-mm-diameter operating proctoscope and significant operating times. Despite this, as measured by ability to defer defecation, number of bowel movements per 24 hours, Fecal Incontinence Severity Index, and Fecal Incontinence Quality of Life survey, transanal endoscopic microsurgery has no detrimental affect on fecal continence.

Anal Canal↗

PubMed2005

Pressure-induced cellular senescence: a mechanism linking venous hypertension to venous ulcers.

INTRODUCTION: Slow healing of ulcers in chronic venous insufficiency (CVI) has long been thought secondary to venous hypertension. Dermal fibroblasts isolated from venous ulcers have morphologies and protein production suggestive of premature aging. In this study, we hypothesized that neonatal fibroblasts (NNF) cultured under elevated pressure will demonstrate premature aging and that this effect will be augmented by an inflammatory mediator, transforming growth factor beta (TGF-beta). MATERIALS AND METHODS: A unique pressure incubator was used to culture NNF at atmospheric pressure (ATM), ATM + 30 mmHg, ATM + 60 mmHg, and ATM +120 mmHg. Some pressure-exposed NNF were also cultured with TGF- beta (1 ng/ml). Growth rates were determined by flow cytometry. Senescent cells were identified by staining with a marker for cellular senescence, beta-galactosidase (SA-beta-Gal). Light microscopy and digital imaging were used to evaluate cell morphology. Paired linear models and comparison of the slopes were used for statistical analysis of growth. chi2 analysis was used to compare senescence rates. RESULTS: NNF cultured at ATM + 60 mmHg and ATM + 120 mmHg showed increased SA-beta-Gal activity (P <0.05), and reduced growth rates (P <0.05) at 11 days. These effects were not seen at ATM + 30 mmHg. NNF grown with TGF-beta did not show augmented SA-beta-Gal staining. CONCLUSIONS: Pressure-exposed NNF demonstrated an accelerated aging phenomenon similar to fibroblasts isolated from venous ulcers. This aging effect was directly related to the level of pressure. TGF-beta did not augment the aging effect. This study suggests that pressure elevations result in altered cell function and accelerated aging that may contribute to the slowed healing seen in patients with venous insufficiency.

Cell Culture Techniques↗

PubMed2005

Use of vena cava filters in pediatric trauma patients: data from the National Trauma Data Bank.

BACKGROUND: Placement of vena cava filters (VCFs) in high-risk adult trauma patients is a well-described intervention for prophylaxis against pulmonary embolism (PE). Few data exist regarding the use of VCFs in pediatric trauma. METHODS: We performed a cross-sectional study using the National Trauma Data Bank of the American College of Surgeons. Patients 17 years old or younger were included. Data regarding demographics, injuries, hospitalization, survival, and treating institution were analyzed. The prevalence of deep vein thrombosis (DVT), PE, and VCF placement were calculated. Odds ratios (ORs) for predictors of VCF placement were determined using multivariate logistic regression. RESULTS: There were 116,357 pediatric patients in the National Trauma Data Bank. VCFs were placed in 214 (0.18%) patients. VCF patients had longer mean hospital (23.99 vs. 4.12 days) and intensive care unit stays (13.65 vs. 1.12 days) and more severe injuries (mean Injury Severity Score, 30.89 vs. 9.04) than those without VCFs. Sixty-five patients had DVT, and PE was diagnosed in 28 patients, representing 0.06% and 0.02% of the cohort, respectively. University-associated teaching hospitals placed 72.4% (95% confidence interval, 65.9-78.3%) of VCFs and Level I trauma centers placed 46.3% (95% confidence interval, 39.4-53.2%) of VCFs. In multivariate analysis, significant predictors of VCF use were DVT (OR, 33.13), spinal cord injury (OR, 15.28), probability of survival (OR, 10.52), severe femur fracture (OR, 3.39), increasing age (OR, 1.99), ISS (OR, 1.05), intensive care unit stay (OR, 1.04), and length of stay (OR, 1.02). Higher Glasgow Coma Scale score decreased the likelihood of VCF use (OR, 0.87). CONCLUSION: Placement of VCFs in pediatric trauma patients is uncommon and is associated with several characteristics of the patient, the injury, and the treating institution. Long-term VCF efficacy in pediatric trauma is not known, and application of VCFs in these patients requires further investigation.

Adolescent↗

PubMed2005

A needs assessment for regionalization of trauma care in a rural state.

Systems of trauma care in urban areas have a demonstrated survival benefit. Little is known of the benefit of trauma system organization in rural areas. We hypothesized that examination of all trauma deaths during a 1-year period would provide opportunities to improve care in our rural state. We used a medical examiner database of trauma deaths occurring during a 1-year period. Five board-certified surgeons analyzed deaths as preventable (P), potentially preventable (PP), and non-preventable (NP) using modified Delphi technique. There were 223 trauma deaths during a 1-year period. Most (63%) died at the scene prior to any medical intervention. Adjudication of the deaths demonstrated 5 P (2%; 95% CI 1-5%), 36 PP (16%; 95% CI 12-27%), and 179 NP (81%; 95% CI 76-86%). Agreement among trauma surgeons was only moderate with a k of 0.46. Suicide accounted for a significant number of the overall trauma deaths at 32 per cent. Rural trauma system design should focus on discovery, as that is where the majority of deaths occur. Suicide is a significant problem in this rural state that should be aggressively targeted with prevention programs.

Female↗

PubMed2004

Improving the TRISS methodology by restructuring age categories and adding comorbidities.

BACKGROUND: The Trauma and Injury Severity Score (TRISS) methodology was developed to predict the probability of survival after trauma. Despite many criticisms, this methodology remains in common use. The purpose of this study was to show that improving the stratification for age and adding an adjustment for comorbidity significantly increases the predictive accuracy of the TRISS model. METHODS: The trauma registry and the hospital administrative database of a regional trauma center were used to identify all blunt trauma patients older than 14 years of age admitted with International Classification of Diseases, Ninth Revision codes 800 to 959 from April 1993 to March 2001. Each individual medical record was then reviewed to ascertain the Revised Trauma Score, the Injury Severity Score, the age of the patients, and the presence of eight comorbidities. The outcome variable was the status at discharge: alive or dead. The study population was divided into two subsamples of equal size using a random sampling method. Logistic regression was used to develop models on the first subsample; a second subsample was used for cross-validation of the models. The original TRISS and three TRISS-derived models were created using different categorizations of Revised Trauma Score, Injury Severity Score, and age. A new model labeled TRISSCOM was created that included an additional term for the presence of comorbidity. RESULTS: There were 5,672 blunt trauma patients, 2,836 in each group. For original TRISS, the Hosmer-Lemeshow statistic (HL) was 179.1 and the area under the receiver operating characteristic (AUROC) curve was 0.873. Sensitivity and specificity were 99.0% and 27.8%, respectively. For the best modified TRISS model, the HL statistic was 20.35, the AUROC curve was 0.902, the sensitivity was 99.0%, and the specificity was 27.8%. For TRISSCOM, the HL statistic was 14.95 and the AUROC curve was 0.918. Sensitivity and specificity were 99.0% and 29.7%, respectively. The difference between the two models almost reached statistical significance (p = 0.086). When TRISSCOM was applied to the cross-validation group, the HL statistic was 10.48 and the AUROC curve was 0.914. The sensitivity was 98.6% and the specificity was 34.9%. CONCLUSION: TRISSCOM can predict survival more accurately than models that do not include comorbidity. A better categorization of age and the inclusion of comorbid conditions in the logistic model significantly improves the predictive performance of TRISS.

Adolescent↗

PubMed2003

A new in vitro model of venous hypertension: the effect of pressure on dermal fibroblasts.

PURPOSE: Venous hypertension leads to venous stasis ulcers. White cell activation, protein leakage from pressurized capillaries, and cytokine imbalances have all been implicated as indirect effects of venous hypertension that contribute to dermal changes seen in chronic venous insufficiency. The direct effect of increased tissue pressures on dermal elements has not been investigated. Prior studies have shown that fibroblasts isolated from venous ulcers have altered growth rates, morphologies, and protein production similar to senescent or aged fibroblasts. We hypothesize that neonatal fibroblasts (NNFs) cultured in conditions of increased atmospheric pressure will demonstrate altered cell function when compared with those grown at normal atmospheric pressure (ATM). METHODS: A pressure incubator was used to culture populations of NNFs at ATM, 60 mm Hg over ATM (ATM + 60 mm Hg), and 120 mm Hg over ATM (ATM + 120 mm Hg). NNF population growth rates were determined by periodic flow cytometry analysis over a 2-week period. Light microscopy and digital imaging were used to evaluate cell morphology. Senescence-associated B-galactosidase (SA-beta-Gal) activity was determined using the X-Gal stain. Fibronectin production was assessed by exposing cells sequentially to anti-fibronectin antibodies and Oregon Green-conjugated goat anti-mouse secondary antibodies. Flow cytometry then was used to determine relative proportions of cells staining positively for fibronectin. Statistical analysis was accomplished with analysis of variance. RESULTS: Populations of cells grown under increased pressures (both ATM + 60 and ATM + 120) showed reduced growth rates (P <.001). Similarly, morphologies of cells grown under pressure had increased cytoplasm to nuclear ratios with abnormal nuclear shapes. Populations of cells grown under pressure had higher percentages of cells staining positive for fibronectin (ATM = 45%, ATM + 60 = 59%, ATM + 120 = 79%). After 14 days of growth under pressure, fibroblast populations did not demonstrate augmented productions of the senescence marker SA-beta-Gal (ATM =.5%, ATM + 60 =.25%, ATM + 120 =.75%). CONCLUSIONS: This study demonstrated that NNFs grown in culture under increased pressures undergo a transformation not seen in cells grown at atmospheric pressure. Cells grown under pressure demonstrated reduced growth rates, increased fibronectin production, and abnormal morphologies similar to fibroblasts isolated from venous ulcers. This study suggests that pressure elevations (like venous hypertension) can directly result in altered cell function and morphology that may contribute to the delayed wound healing seen in patients with venous ulcers. This model uses a pressurized incubator that may prove to be a valuable adjunct in studying the effects of venous hypertension.

Atmospheric Pressure↗

PubMed2003

Charges and reimbursement at a rural level I trauma center: a disparity between effort and reward among professionals.

BACKGROUND: A Level I trauma center must provide immediate availability general (trauma) surgical expertise. In the current practice few patients require a general surgical procedure. The expertise of subspecialists may also be required and frequently these patients will require subspecialty operative care. We hypothesized that trauma surgeons would receive less reimbursement than their subspecialty colleagues despite a greater commitment of time and effort in taking care of the multiply-injured patient. METHODS: Three fellowship trained trauma surgeons were specifically hired to cover the trauma service for the year 2000. Professional billings, contribution to margin (reimbursement minus direct costs) of the trauma surgeons and subspecialists were obtained from the hospital financial information system. A surrogate for effort was assessed by the number of attending notes in the chart. A surrogate for complexity of care was assessed by the length of notes in the chart. Weekly time sheets assessed the percentage of time involved in the care of trauma patients. RESULTS: There were 344 patients cared for exclusively on the trauma service for the year 2000. The billing generated per patient was $1005 for the trauma surgeon, $5904 for the subspecialists, and $27,554 for the hospital. Orthopedics and radiology generated more professional billing on the trauma patients than the trauma surgeons. The trauma surgeons spent 52% of their weekly clinical activity in the care of trauma patients, yet this activity accounted for only 16% of their billings (the rest came from general surgery and ICU care). The effort and complexity of care provided by the trauma surgeons was significantly greater than the subspecialists. CONCLUSION: The Level I trauma service is a conduit for patients coming into the hospital that provides a significant remuneration to the subspecialty services. Trauma surgeons are able to bill much less than many of their subspecialty colleagues despite expending significantly greater amounts of time and effort in the care of these patients. Strategies for improved reimbursement for trauma surgeons must be devised or trauma surgery will suffer the same fate as other areas of surgery, losing our brightest and best to more financially sound subspecialty services such as radiology and orthopedics.

Adult↗

PubMed2003

A fresh set of survival risk ratios derived from incidents in the National Trauma Data Bank from which the ICISS may be calculated.

BACKGROUND: Survival risk ratios (SRRs) are database-specific point estimates of survival associated with each injury International Classification of Diseases, Ninth Revision (ICD-9) code. They are derived for each injury code by dividing the number of patients who survive the code by the total number of patients that display the code. SRRs are used to measure injury severity and distribution and are most prominently featured in the ICD-9 Injury Severity Score (ICISS), which is the product of a patient's SRRs. Because SRRs are important for trauma scoring, it is important that they be derived from a representative trauma population. The purpose of this study was to compare a new set of SRRs derived from the National Trauma Data Bank (NTDB) with SRRs derived years ago from the North Carolina Hospital Discharge Database (NCHDD). METHODS: Tests for differences of proportions were applied to determine which ICD-9 codes have significantly different SRRs in an attempt to characterize the database differences. Two different ICISSs were calculated for 170,853 eligible patients using the two different sets of SRRs, NCHDD and NTDB. The NTDB SRRs were calculated and applied using a 10-fold cross-validation to avoid bias in estimation. Estimates of discrimination for both ICISSs were calculated using the area under the receiver-operating characteristic curve. R2 and Akaike information criterion statistics were compared. RESULTS: A modest statistical case is made for using the NTDB SRRs rather than the NCHDD SRRs. CONCLUSION: Researchers should begin using the NTDB SRRs for their outcome modeling and for ICISS calculation.

Databases as Topic↗

PubMed2002

Fecal incontinence severity index after fistulotomy: a predictor of quality of life.

PURPOSE: The purpose of this study was to use the Fecal Incontinence Severity Index to assess fecal incontinence after fistulotomy and to correlate the Fecal Incontinence Severity Index score with quality-of-life measures. METHODS: A retrospective chart review was performed on consecutive patients undergoing fistulotomy by a single colon and rectal surgeon at a university hospital from 1991 to 1999. Demographics, fistula anatomy, surgical technique, and length of follow-up were recorded. Mailed questionnaires and telephone interviews were conducted to determine the Fecal Incontinence Severity Index score, pad usage, lifestyle restriction, and psychosocial factors. A linear regression model was used to determine the relationship of clinical factors with Fecal Incontinence Severity Index. One-way ANOVA was used to correlate Fecal Incontinence Severity Index with quality-of-life measures. RESULTS: Of 110 patients who underwent fistulotomy, 96 (88 percent) had complete follow-up. Mean age was 48 (range, 17-84) years, and 68 percent were male. Follow-up was less than two years in 26 percent, two to five years in 39 percent, and more than five years in 35 percent. Of these patients, 41 percent had intersphincteric fistulas, whereas 59 percent had transsphincteric fistulas. Median Fecal Incontinence Severity Index score was 6, with a mean of 13 (maximum Fecal Incontinence Severity Index = 61); 36 percent had a Fecal Incontinence Severity Index score of zero. Linear regression revealed that only the amount of external sphincter divided correlated with Fecal Incontinence Severity Index score (P = 0.05). Quality-of-life measures strongly correlated with Fecal Incontinence Severity Index by analysis of variance (P < 0.01 for pad usage, lifestyle restriction, depression, and embarrassment), with substantial quality-of-life drop-off documented with Fecal Incontinence Severity Index >30. CONCLUSION: The Fecal Incontinence Severity Index is an excellent tool to gauge quality of life after fistulotomy. Fecal Incontinence Severity Index scores >30 predict a detrimental effect on quality of life.

Adolescent↗

PubMed2002

A comparison of the abilities of nine scoring algorithms in predicting mortality.

OBJECTIVE: The purpose of this study was to compare the abilities of nine Abbreviated Injury Scale (AIS)- and (ICD-9)-based scoring algorithms in predicting mortality. METHODS: The scores collected on 76,871 incidents consist of four AIS-based algorithms (Injury Severity Score [ISS], New Injury Severity Score, Anatomic Profile Score [APS], and maximum AIS [maxAIS]), their four ICD to AIS mapped counterparts, and the ICD-9-based ISS (ICISS). A 10-fold cross-validation was performed and area under the receiver operating characteristic curve was used to determine algorithm discrimination. Hosmer-Lemeshow statistics were computed to gauge goodness-of-fit, and model refinement measured variance of predicted probabilities. RESULTS: Overall, the ICISS has the best discrimination and model refinement, whereas the APS has the best Hosmer-Lemeshow performance. ICD-9 to AIS mapped scores have worse discrimination than their AIS-based counterparts, but still show moderate performance. CONCLUSION: Differences in performance were relatively small. Complex scores such as the ICISS and the APS provide improvement in discrimination relative to the maxAIS and the ISS. Trauma registries should move to include the ICISS and the APS. The ISS and maxAIS perform moderately well and have bedside benefits.

Abbreviated Injury Scale↗

PubMedDate not supplied

Do proton pump inhibitors increase the incidence of nosocomial pneumonia and related infectious complications when compared with histamine-2 receptor antagonists in critically ill trauma patients?

BACKGROUND: Proton pump inhibitors (PPI) may increase the risk of nosocomial pneumonia caused by profound irreversible gastric acid suppression. The study purpose was to characterize differences in nosocomial pneumonia and related infections in trauma patients administered either histamine2-receptor antagonists (H2RA) or PPI. METHODS: Observational evaluation of consecutive critically ill adult trauma patients administered either omeprazole or famotidine during a 22-month period. Nosocomial infection was evaluated daily based on published CDC definitions. RESULTS: Eighty of 269 patients fulfilled study criteria. The PPI group (n = 40) exhibited increased baseline risk for infection, demonstrated by higher ISS (p = 0.020), more chest tube placements (p = 0.031), and increased chest trauma (p = 0.025). Overall number of patients infected per group included 33% and 40% of patients administered PPI and H2RA, respectively (p = 0.64). Despite baseline differences, the incidence of nosocomial infection was similar (p = 0.87), and extrapolation of pneumonia based on 1000 patient days revealed a ratio 51.7 vs 52.2 in the PPI vs H2RA groups, respectively, which was not significant (p = 0.99). CONCLUSIONS: Proton pump inhibitor administration does not increase risk of nosocomial pneumonia or other nosocomial infections compared with H2RA therapy in the critically ill trauma patient.

Adolescent↗