ABSTRACT
BACKGROUND: Practice guidelines from the National Comprehensive Cancer Network and the American Society of Clinical Oncology recommend pathologic mediastinal staging and surgical resection for patients with clinically node-negative T1/T2 small cell lung cancer (SCLC), but the extent to which surgery is used is unknown. We sought to assess trends and practice patterns in the use of surgery for SCLC. METHODS: T1 or T2N0M0 SCLC cases were identified in the National Cancer Database (NCDB), 2004-2013. Characteristics of patients undergoing resection were analyzed. Hierarchical logistic regression was used to identify individual and hospital-level predictors of receipt of surgery, adjusting for clinical, demographic and facility characteristics. Trends in resection rates were analyzed over the study period. FINDINGS: 9740 patients were identified with clinical T1 or T2 N0M0 SCLC. Of these, 2210 underwent surgery (22.7%), with 1421 (64.3%) undergoing lobectomy, 739 (33.4%) sublobar resections and 50 (2.3%) pneumonectomies. After adjustment, Medicaid patients were less likely to receive surgery (OR0.65 95% CI 0.48-0.89, p=0.006), as were those with T2 tumors (OR0.25 CI0.22-0.29, p<0.0001). Academic facilities were more likely to resect eligible patients (OR 1.90 CI1.45-2.49, p<0.0001). Between 2004 and 2013, resection rates more than doubled from 9.1% to 21.7%. Overall, 68.7% of patients were not offered surgery despite having no identifiable contraindication. In patients not receiving surgery, only 7% underwent pathologic mediastinal staging. INTERPRETATION: Rates of resection are increasing, but two thirds of potentially eligible patients fail to undergo surgery. Further study is required to address the lack of concordance between guidelines and practice.
Subject(s)
Carcinoma, Small Cell/epidemiology , Lung Neoplasms/epidemiology , Pneumonectomy/statistics & numerical data , Academic Medical Centers , Aged , Carcinoma, Small Cell/surgery , Databases, Factual , Female , Humans , Lung Neoplasms/surgery , Male , Medicaid , Middle Aged , Neoplasm Staging , Patient Selection , Practice Guidelines as Topic , Practice Patterns, Physicians' , Risk Factors , United States/epidemiologyABSTRACT
BACKGROUND: The role of surgery in small cell lung cancer (SCLC) is controversial. Survival outcomes for resection of stage I-IIIA SCLC compared to chemotherapy-based non-surgical treatment (NST) were examined using propensity matching. METHODS: 29,994 clinical stage I-IIIA SCLC patients, including 2,619 undergoing surgery, were identified in the National Cancer Database. Stage-specific propensity scores for receipt of surgery were created. Resected patients were matched 1:1 to those undergoing NST. Overall survival (OS) was assessed using Kaplan-Meier and multivariable Cox models. A separate match was performed comparing Stage I/II patients aged <85 with a Charlson score of 0 who underwent lobectomy with adjuvant chemotherapy (and radiotherapy if node positive) to those treated with multiagent chemotherapy and concurrent chest radiotherapy (CRT) of at least 40 gray. RESULTS: 2,089 patients were matched, and cohorts were well balanced. Surgery was associated with longer survival for Stage I (median OS 38.6 months vs. 22.9 months, HR 0.62 95%CI 0.57-0.69, p<0.0001), but survival differences were attenuated for Stage II (median OS 23.4 months vs. 20.7 months, HR 0.84 95%CI 0.70-1.01, p=0.06) and IIIA (median OS 21.7 vs. 16.0 months, HR 0.71 95%CI 0.60-0.83, p <0.0001). In analyses by T and N stage, longer OS was observed in resected patients with stage T3/T4 N0 (median OS 33.0 vs. 16.8 months, p=0.008) and node positivity(N1+ 24.4 vs. 18.3 months p=0.03; N2+ 20.1 vs. 14.6 months p=0.007). In the subgroup analysis, 507 stage I/II patients receiving lobectomy and adjuvant chemotherapy were matched to patients receiving concurrent CRT. In this cohort, lobectomy with adjuvant chemotherapy was associated with significantly longer survival (median OS 48.6 vs. 28.7 months, p<0.0001). CONCLUSIONS: Surgical resection is associated with significantly longer survival for early SCLC. New randomized trials should assess trimodality therapy in stages I/II, and in node negative disease.
Subject(s)
Carcinoma, Small Cell/therapy , Lung Neoplasms/therapy , Pneumonectomy , Aged , Carcinoma, Small Cell/mortality , Carcinoma, Small Cell/pathology , Cohort Studies , Drug Therapy , Early Diagnosis , Female , Humans , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Propensity Score , Radiotherapy , Survival AnalysisABSTRACT
The rowi is a critically endangered species of kiwi. Young birds on a crèche island showed loss of feathers from the ventral abdomen and a scurfy dermatitis of the abdominal skin and vent margin. Histology of skin biopsies identified cutaneous larval migrans, which was shown by molecular sequencing to be possibly from a species of Trichostrongylus as a cause of ventral dermatitis and occasional ulcerative vent dermatitis. The predisposing factors that led to this disease are suspected to be the novel exposure of the rowi to parasites from seabirds or marine mammals due to the island crèche and the limited management of roost boxes. This is the first instance of cutaneous larval migrans to be recorded in birds. Severe and fatal complications of the investigation resulted in the death of eight birds of aspergillosis and pulmonary complications associated with the use of bark as a substrate in hospital. Another bird died of renal failure during the period of hospitalisation despite oral and intravenous fluid therapy. The initiating cause of the renal failure was not determined. These complications have the potential to undermine the working relationship between wildlife veterinarians and conservation managers. This case highlights that intensive conservation management can result in increased opportunities for novel routes of cross-species pathogen transmission.
ABSTRACT
The external effects of oil on wildlife can be obvious and acute. Internal effects are more difficult to detect and can occur without any external signs. To quantify internal effects from oil ingestion by wildlife during an oil spill, baseline levels of ubiquitous hydrocarbon fractions, like polycyclic aromatic hydrocarbons (PAHs), need to be established. With these baseline values the extent of impact from exposure during a spill can be determined. This research represents the first investigation of baseline levels for 22 PAHs in New Zealand coastal and marine avian wildlife. Eighty-five liver samples were tested from 18 species. PAHs were identified in 98% of livers sampled with concentrations ranging from 0 to 1341.6 ng/g lipid wt or on wet wt basis, 0 to 29.5 ng/g. Overall, concentrations were low relative to other globally reported avian values. PAH concentration variability was linked with species foraging habitat and migratory patterns.
Subject(s)
Birds/metabolism , Environmental Monitoring , Polycyclic Aromatic Hydrocarbons/metabolism , Animals , Ecosystem , New Zealand , Petroleum Pollution , Polycyclic Aromatic Hydrocarbons/analysis , Polycyclic Aromatic Hydrocarbons/standards , Surveys and QuestionnairesABSTRACT
Biomonitoring of blood is commonly used to identify and quantify occupational or environmental exposure to chemical contaminants. Increasingly, this technique has been applied to wildlife contaminant monitoring, including for green turtles, allowing for the non-lethal evaluation of chemical exposure in their nearshore environment. The sources, composition, bioavailability and toxicity of metals in the marine environment are, however, often unknown and influenced by numerous biotic and abiotic factors. These factors can vary considerably across time and space making the selection of the most informative elements for biomonitoring challenging. This study aimed to validate an ICP-MS multi-element screening method for green turtle blood in order to identify and facilitate prioritisation of target metals for subsequent fully quantitative analysis. Multi-element screening provided semiquantitative results for 70 elements, 28 of which were also determined through fully quantitative analysis. Of the 28 comparable elements, 23 of the semiquantitative results had an accuracy between 67% and 112% relative to the fully quantified values. In lieu of any available turtle certified reference materials (CRMs), we evaluated the use of human blood CRMs as a matrix surrogate for quality control, and compared two commonly used sample preparation methods for matrix related effects. The results demonstrate that human blood provides an appropriate matrix for use as a quality control material in the fully quantitative analysis of metals in turtle blood. An example for the application of this screening method is provided by comparing screening results from blood of green turtles foraging in an urban and rural region in Queensland, Australia. Potential targets for future metal biomonitoring in these regions were identified by this approach.
Subject(s)
Environmental Monitoring/methods , Metals/blood , Turtles/blood , Water Pollutants, Chemical/blood , Animals , QueenslandABSTRACT
It is unknown whether healthcare workers' facial hair harbours nosocomial pathogens. We compared facial bacterial colonization rates among 408 male healthcare workers with and without facial hair. Workers with facial hair were less likely to be colonized with Staphylococcus aureus (41.2% vs 52.6%, P = 0.02) and meticillin-resistant coagulase-negative staphylococci (2.0% vs 7.0%, P = 0.01). Colonization rates with Gram-negative organisms were low for all healthcare workers, and Gram-negative colonization rates did not differ by facial hair type. Overall, colonization is similar in male healthcare workers with and without facial hair; however, certain bacterial species were more prevalent in workers without facial hair.
Subject(s)
Bacterial Infections/microbiology , Biota , Carrier State/microbiology , Hair/microbiology , Health Personnel , Adult , Bacterial Infections/epidemiology , Carrier State/epidemiology , Cross-Sectional Studies , Hospitals , Humans , Male , Middle Aged , Prevalence , Young AdultSubject(s)
Endometritis/complications , Pyometra/complications , Uterine Perforation/etiology , Endometritis/pathology , Endometritis/surgery , Female , Humans , Hysterectomy , Middle Aged , Necrosis , Ovariectomy , Peritonitis/etiology , Peritonitis/therapy , Pyometra/pathology , Pyometra/surgery , Salpingectomy , Tomography, X-Ray Computed , Uterine Perforation/surgeryABSTRACT
BACKGROUND: Eradication of Helicobacter pylori after peptic ulcer haemorrhage reduces the risk of recurrence. Because H. pylori treatment is very effective, it is unclear whether testing to confirm eradication is worthwhile. AIMS: To examine whether patients with H. pylori-associated peptic ulcer haemorrhage should be tested for successful eradication after completion of antibiotic therapy. METHODS: A Markov cost-effectiveness model was developed to compare testing vs. non-testing of H. pylori eradication in peptic ulcer haemorrhage. Probability estimates and average costs were derived from published information. RESULTS: Testing for H. pylori eradication resulted in a benefit of 0.07 quality-adjusted life-years and cost 836 US dollars less than the strategy of not confirming eradication. Testing remained the superior strategy when varying the model regarding age, the initial success of eradication, various test and retreatment strategies, and the rate and costs of recurrent bleeding. Assuming a high eradication rate (95%), the test strategy becomes more expensive only if the cost of H. pylori testing reaches 265 US dollars; however, even under these conditions it remains cost-effective. CONCLUSIONS: Patients with H. pylori-associated peptic ulcer bleeding should be tested to confirm eradiation of H. pylori after completion of antibiotic treatment.
Subject(s)
Helicobacter Infections/diagnosis , Helicobacter pylori , Peptic Ulcer Hemorrhage/prevention & control , Cost-Benefit Analysis , Family Practice/economics , Female , Helicobacter Infections/economics , Helicobacter Infections/prevention & control , Humans , Male , Markov Chains , Mass Screening/economics , Middle Aged , Models, Economic , Peptic Ulcer Hemorrhage/microbiology , Quality-Adjusted Life Years , RecurrenceABSTRACT
BACKGROUND: Because of the growing interest in surgery to treat morbid obesity, this study examined changes in the utilization and in-hospital outcomes of bariatric surgery in the United States over a 10-year period. METHODS: Data were obtained from the Nationwide Inpatient Sample, the largest all-payer discharge database in the United States. International Classification of Disease (ICD-9) codes were used to identify all bariatric procedures performed for adults from 1990 to 2000. Population-based rates of surgery for each year were calculated by applying sampling weights and U.S. Census data. Secular trends in annual rates of surgery, changes in patient characteristics, and in-hospital mortality and complications were analyzed. RESULTS: From 1990 to 2000, the national annual rate of bariatric surgery increased nearly six fold, from 2.4 to 14.1 per 100,000 adults (p = 0.001). There has been more than a ninefold increase in the use of gastric bypass procedures (1.4 to 13.1 per 100,000; p < 0.001). This represents an increase from 55% of all bariatric procedures in 1990 to 93% of such procedures in 2000 (p < 0.001). The rates of in-hospital mortality were low (0.4% overall), but increased slightly over time (0.2% in 1990 to 0.5% in 2000; p = 0.009). There is no significant difference in adjusted mortality for the past 8 years, but a slight rise did occur over the full 10-year period. The rates for reoperation (1.3%) and pulmonary emboli (0.3%) remained stable. The rates for respiratory failure associated with bariatric surgery declined from 7.7% in 1990 to 4.5% in 2000 (p < 0.001). Over this time, the mean length of hospital stay declined from 6.0 to 4.1 days (p < 0.001). CONCLUSIONS: The annual rate of bariatric surgery in the United States increased nearly six fold between 1990 and 2000, with little change in in-hospital morbidity and mortality. This appears to be driven largely by the increasing popularity of gastric bypass procedures.
Subject(s)
Bariatric Surgery/trends , Adult , Bariatric Surgery/mortality , Bariatric Surgery/statistics & numerical data , Comorbidity , Databases, Factual , Female , Gastric Bypass/statistics & numerical data , Gastroplasty/statistics & numerical data , Hospital Mortality , Humans , Length of Stay/statistics & numerical data , Male , Middle Aged , Obesity/epidemiology , Obesity/surgery , Patient Discharge/statistics & numerical data , Postoperative Complications/epidemiology , Pulmonary Embolism/epidemiology , Pulmonary Embolism/etiology , Reoperation/statistics & numerical data , Treatment Outcome , United States/epidemiologyABSTRACT
BACKGROUND: Although ventral hernia repair is increasingly performed laparoscopically, complication rates with this procedure are not well characterized. For this reason, we performed a prospective study comparing early outcomes after laparoscopic and open ventral hernia repairs. METHODS: We identified all the patients undergoing ventral (including incisional) hernia repair at a single tertiary care center between September 1, 1999 and July 1, 2001 (overall n = 257). To increase the homogeneity of the sample, we excluded umbilical hernia repairs, parastomal hernia repairs, nonelective procedures, procedures not involving mesh, and repairs performed concurrently with another surgical procedure. Postoperative complications (in-hospital or within 30-days) were assessed prospectively according to standardized definitions by trained nurse clinicians. RESULTS: Of the 136 ventral hernia repairs that met the study criteria, 65 (48%) were laparoscopic repairs (including 3 conversions to open surgery) and 71 (52%) were open repairs. The patients in the laparoscopic group were more likely to have undergone a prior (failed) ventral hernia repair (40% vs 27%; p = 0.14), but other patient characteristics were similar between the two groups. Overall, fewer complications were experienced by patients undergoing laparoscopic repair (8% vs 21%; p = 0.03). The higher complication rate in the open ventral hernia repair group came from wound infections (8%) and postoperative ileus (4%), neither of which was observed in the patients who underwent laparoscopic repair. The laparoscopic group had longer operating room times (2.2 vs 1.7 h; p = 0.001), and there was a nonsignificant trend toward shorter hospital stays with laparoscopic repair (1.1 vs 1.5 days; p = 0.10). CONCLUSIONS: The patients undergoing laparoscopic repair had fewer postoperative complications than those receiving open repair. Wound infections and postoperative ileus accounted for the higher complication rates in the open ventral hernia repair group. Otherwise, these groups were very similar. Long-term studies assessing hernia recurrence rates will be required to help determine the optimal approach to ventral hernia repair.
Subject(s)
Hernia, Ventral/surgery , Laparoscopy/statistics & numerical data , Postoperative Complications/epidemiology , Abscess/epidemiology , Abscess/etiology , Female , Humans , Ileus/epidemiology , Ileus/etiology , Incidence , Intestines/injuries , Length of Stay/statistics & numerical data , Male , Middle Aged , Peritonitis/epidemiology , Peritonitis/etiology , Postoperative Complications/etiology , Prospective Studies , Respiratory Insufficiency/epidemiology , Respiratory Insufficiency/etiology , Surgical Mesh , Surgical Wound Dehiscence/epidemiology , Surgical Wound Dehiscence/etiology , Surgical Wound Infection/epidemiology , Surgical Wound Infection/etiologyABSTRACT
BACKGROUND: Studies examining the outcomes of surgery for gastroesophageal reflux disease (GERD) have consisted primarily of case series. We sought to assess trends in both utilization and outcomes of antireflux surgery from a national perspective. METHODS: Using ICD-9 codes, we identified all antireflux procedures (N = 24,208) performed on adults from 1990 to 1997 in hospitals participating in the Nationwide Inpatient Sample, the largest all-payer inpatient care database in the United States. Using sampling weights and U.S. Census data, we then calculated the national population-based rate of antireflux surgery for each year and examined secular trends in utilization, in-hospital mortality, splenectomy (a technical complication), and length of hospital stay. Using a coding algorithm, we also assessed trends in the proportion of procedures performed via the laparoscopic, open abdominal, and thoracic approaches. RESULTS: From 1990 to 1997, the population-based annual rate of antireflux surgery increased from 4.4 to 12.0 per 100,000 adults. A substantial increase in utilization was observed from 1993 to 1995, but annual rates before and after this period were relatively stable. Between 1990 and 1997, in-hospital surgical mortality decreased from 1.2% to 0.5% (p = 0.002), splenectomy rates decreased from 3.9% to 1.5% (p <0.001), and median length of stay decreased from 7 to 2 days (p <0.01). The proportion of antireflux procedures performed laparoscopically increased from 0.5% to 64% (p <0.001), and the proportion of procedures performed using a thoracic approach decreased from 12% to 1% (p <0.001). CONCLUSIONS: With the dissemination of the laparoscopic approach, the population-based rate of antireflux surgery has more than doubled. At the same time, operative mortality and splenectomy risks have diminished.
Subject(s)
Fundoplication/statistics & numerical data , Fundoplication/trends , Gastroesophageal Reflux/surgery , Adult , Age Distribution , Female , Fundoplication/mortality , Gastroesophageal Reflux/mortality , Health Care Surveys/statistics & numerical data , Humans , Laparoscopy/mortality , Laparoscopy/statistics & numerical data , Laparoscopy/trends , Length of Stay/statistics & numerical data , Male , Middle Aged , Patient Discharge/statistics & numerical data , Population Surveillance , Sex Distribution , Splenectomy/mortality , Splenectomy/statistics & numerical data , Splenectomy/trends , Treatment Outcome , United StatesABSTRACT
Recent research has highlighted the role of expressed emotion by ward staff in determining the well-being of psychiatric inpatients. Existing methods of assessing staff expressed emotion involve standardized interviews and are expensive and time-consuming. We report the development of a questionnaire measure of expressed emotion in staff as perceived by patients. In study 1, factor analysis of items administered to patients in a variety of settings led to the development of a questionnaire with three subscales: supportiveness, criticism and intrusiveness. In study 2, the test-retest reliability of the questionnaire was found to be adequate, and some evidence of concurrent validity for the scale was obtained against expressed emotion rated from staff speech samples. In study 3, the scale was shown to have good concurrent validity against the ward atmosphere scale, and scores were found to be independent of insight or experience of admission to hospital. The perceived expressed emotion in staff scale is a convenient measure, which may have utility for both research and clinical purposes.
Subject(s)
Attitude of Health Personnel , Expressed Emotion , Mental Health Services , Perception , Adult , Aged , Female , Health Care Surveys , Humans , Male , Middle AgedABSTRACT
BACKGROUND: Although several randomized trials have compared postoperative outcomes in patients undergoing open and laparoscopic appendectomy, few have examined whether laparoscopy has affected preoperative decision making. We hypothesized that surgeon enthusiasm for laparoscopic appendectomy would lower the threshold to operate on patients with possible appendicitis. To examine this question we designed a retrospective cohort study in the setting of a tertiary care medical center. METHODS: We studied a consecutive series of 130 patients taken to the operating room with preoperative diagnoses of appendicitis between 1 January 1997 and 31 December 1999. We excluded pregnant patients, those under 18 or over 75, those admitted electively for chronic symptoms, and those undergoing appendectomy incidental to another procedure. Measures included the proportion of patients with normal appendices or acute appendicitis (perforated and nonperforated), as determined from the pathology report. Other clinical and demographic data were obtained by review of the medical records. RESULTS: During the study period, 87 patients (67%) underwent open appendectomy and 43 patients (33%) underwent laparoscopic appendectomy. Women were more likely to receive the laparoscopic approach than men (43% vs 24% p = 0.021). Preoperative use of advanced imaging tests (computed tomography or ultrasound) was more prevalent in the laparoscopic group (40% vs 30%, p = 0.271). Patients undergoing the laparoscopic procedure were considerably less likely to have acute appendicitis than those undergoing an open one (67% vs 92%, p <0.001). However, among patients with confirmed appendicitis, those undergoing laparoscopic surgery were less likely to be perforated than those who had an open procedure (4.6% vs 25% p = 0.004). CONCLUSION: At our hospital, the availability of the laparoscopic approach to appendectomy may have lowered the threshold to operate on patients with possible appendicitis, as reflected in higher negative exploration rates and lower rates of perforated appendicitis.
Subject(s)
Appendicitis/diagnosis , Appendicitis/surgery , Laparoscopy/methods , Acute Disease , Adult , Appendectomy/methods , Appendectomy/statistics & numerical data , Appendicitis/diagnostic imaging , Cohort Studies , Databases as Topic , Decision Making , Female , Hospitals, Rural , Humans , Intestinal Perforation/etiology , Intraoperative Complications/etiology , Laparoscopy/statistics & numerical data , Male , Preoperative Care/methods , Preoperative Care/statistics & numerical data , Radionuclide Imaging , Retrospective Studies , Sex Factors , Tomography, X-Ray Computed/methods , Tomography, X-Ray Computed/statistics & numerical data , UltrasonographyABSTRACT
BACKGROUND: Several studies have reported lower perioperative mortality rates with pancreaticoduodenectomy at high-volume hospitals than at low-volume hospitals. We sought to determine whether volume is also related to survival after hospital discharge. METHODS: Using information from the Medicare claims database, we performed a retrospective cohort study of all 7229 patients over age 65 undergoing pancreaticoduodenectomy in the United States between 1992 and 1995. We divided the study population into approximate quartiles according to their hospital's average annual volume of pancreaticoduodenectomies in Medicare patients: very low (< 1/y), low (1-2/y, medium (2-5/y), and high (5+/y). To adjust for potentially confounding variables, we used a Cox proportional hazards model to examine relationships between hospital volume and mortality, our primary outcome measure. RESULTS: Overall, 3-year survival was higher at high-volume centers (37%) than at medium- (29%), low- (26%), and very low volume hospitals (25%) (log-rank P < .0001). After excluding perioperative deaths and adjusting for case-mix, patients undergoing surgery at high-volume hospitals remained less likely to experience late mortality than patients at very low volume centers (adjusted hazard ratio 0.69, 95% CI 0.62-0.76). Relationships between hospital volume and survival after discharge were not restricted to patients with cancer diagnoses; patients with benign disease had similar improvements in late survival after surgery at high-volume centers. CONCLUSIONS: Hospital volume strongly influences both perioperative risk and long-term survival after pancreaticoduodenectomy. Our data suggest that both patient selection and differences in quality of care may underlie better outcomes at high-volume referral centers.
Subject(s)
Hospitalization/statistics & numerical data , Pancreaticoduodenectomy/mortality , Aged , Female , Humans , Male , Survival Rate , United StatesABSTRACT
PURPOSE: Because endovascular repair of abdominal aortic aneurysms (AAAs) is less invasive, some investigators have suggested that this increasingly popular technique should broaden the indications for elective AAA repair. The purpose of this study was to calculate quality-adjusted life expectancy rates after endovascular and open AAA repair and to estimate the optimal diameter for elective AAA repair in hypothetical cohorts of patients at average risk and at high risk. METHODS: A Markov decision analysis model was used in this study. Assumptions were made on the basis of published reports and included the following: (1) the annual rupture rate is a continuous function of the AAA diameter (0% for <4 cm, 1% for 4.5 cm, 11% for 5.5 cm, and 26% for 6.5 cm); (2) the operative mortality rate is 1% for endovascular repair (excluding the risk of conversion to open repair) and 3.5% for open repair at age 70 years; and (3) immediate endovascular-to-open conversion risk is 5%, and late conversion rate is 1% per year. The main outcome measure in this study was the benefit of AAA repair in quality-adjusted life years (QALYs). The optimal threshold size (the AAA diameter at which elective repair maximizes benefit) was measured in centimeters. RESULTS: The benefit of endovascular repair is consistently greater than that of open repair, but the additional benefit is small-0.1 to 0.4 QALYs. For men in average health with gradually enlarging AAAs with initial diameters of 4 cm, endovascular surgery reduces the optimal threshold diameter by very little: from 4.6 to 4.6 cm (no change) at age 60 years, from 4.8 to 4.7 cm at age 70 years, and from 5.1 to 4.9 cm at age 80 years. For older men in poor health, endovascular surgery reduces the optimal threshold diameter substantially (8.1 to 5.7 cm at age 80 years), but the benefit of repair in this population is small (0.2 QALYs). CONCLUSION: For most patients, the indications for AAA repair are changed very little by the introduction of endovascular surgery. Only for older patients in poor health does endovascular surgery substantially lower the optimal threshold diameter for elective AAA repair.
Subject(s)
Aortic Aneurysm, Abdominal/pathology , Aortic Aneurysm, Abdominal/surgery , Decision Support Techniques , Elective Surgical Procedures/statistics & numerical data , Endoscopy/statistics & numerical data , Markov Chains , Quality-Adjusted Life Years , Vascular Surgical Procedures/methods , Age Factors , Aged , Aged, 80 and over , Elective Surgical Procedures/mortality , Endoscopy/mortality , Humans , Male , Middle Aged , Models, Statistical , Outcome Assessment, Health Care , Patient Selection , Risk Factors , Sensitivity and Specificity , United States/epidemiology , Vascular Surgical Procedures/mortalityABSTRACT
Mutant sorghum (Sorghum bicolor [L.] Moench) deficient in functional phytochrome B exhibits reduced photoperiodic sensitivity and constitutively expresses a shade-avoidance phenotype. Under relatively bright, high red:far-red light, ethylene production by seedlings of wild-type and phytochrome B-mutant cultivars progresses through cycles in a circadian rhythm; however, the phytochrome B mutant produces ethylene peaks with approximately 10 times the amplitude of the wild type. Time-course northern blots show that the mutant's abundance of the 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase mRNA SbACO2 is cyclic and is commensurate with ethylene production, and that ACC oxidase activity follows the same pattern. Both SbACO2 abundance and ACC oxidase activity in the wild-type plant are very low under this regimen. ACC levels in the two cultivars did not demonstrate fluctuations coincident with the ethylene produced. Simulated shading caused the wild-type plant to mimic the phenotype of the mutant and to produce high amplitude rhythms of ethylene evolution. The circadian feature of the ethylene cycle is conditionally present in the mutant and absent in the wild-type plant under simulated shading. SbACO2 abundance in both cultivars demonstrates a high-amplitude diurnal cycle under these conditions; however, ACC oxidase activity, although elevated, does not exhibit a clear rhythm correlated with ethylene production. ACC levels in both cultivars show fluctuations corresponding to the ethylene rhythm previously observed. It appears that at least two separate mechanisms may be involved in generating high-amplitude ethylene rhythms in sorghum, one in response to the loss of phytochrome B function and another in response to shading.
Subject(s)
Ethylenes/biosynthesis , Phytochrome/metabolism , Poaceae/genetics , Poaceae/metabolism , Amino Acid Oxidoreductases/genetics , Amino Acid Oxidoreductases/metabolism , Base Sequence , Circadian Rhythm , DNA Primers/genetics , Genes, Plant , Light , Molecular Sequence Data , Mutation , Poaceae/radiation effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Plant/genetics , RNA, Plant/metabolismABSTRACT
BACKGROUND: Reports of better results at national referral centers than at low-volume community hospitals have prompted calls for regionalizing pancreaticoduodenectomy (the Whipple procedure). We examined the relationship between hospital volume and mortality with this procedure across all US hospitals. METHODS: Using information from the Medicare claims database, we performed a national cohort study of 7229 Medicare patients more than 65 years old undergoing pancreaticoduodenectomy between 1992 and 1995. We divided the study population into approximate quartiles according to the hospital's average annual volume of pancreaticoduodenectomies in Medicare patients: very low (< 1/y), low (1-2/y), medium (2-5/y), and high (5+/y). Using multivariate logistic regression to account for potentially confounding patient characteristics, we examined the association between institutional volume and in-hospital mortality, our primary outcome measure. RESULTS: More than 50% of Medicare patients a undergoing pancreaticoduodenectomy received care at hospitals performing fewer than 2 such procedures per year. In-hospital mortality rates at these low- and very-low-volume hospitals were 3- to 4-fold higher than at high-volume hospitals (12% and 16%, respectively, vs 4%, P < .001). Within the high-volume quartile, the 10 hospitals with the nation's highest volumes had lower mortality rates than the remaining high-volume centers (2.1% vs 6.2%, P < .01). The strong association between institutional volume and mortality could not be attributed to patient case-mix differences or referral bias. CONCLUSIONS: Although volume-outcome relationships have been reported for many complex surgical procedures, hospital experience is particularly important with pancreaticoduodenectomy. Patients considering this procedure should be given the option of care at a high-volume referral center.
Subject(s)
Clinical Competence/statistics & numerical data , Hospital Mortality , Hospitals, Community/statistics & numerical data , Pancreaticoduodenectomy/mortality , Patient Admission/statistics & numerical data , Aged , Cohort Studies , Female , Humans , Logistic Models , Male , Medicare , Outcome Assessment, Health Care , United States/epidemiologyABSTRACT
BACKGROUND: Regionalization of high-risk surgical procedures to selected high-volume centers has been proposed as a way to reduce operative mortality. For patients, however, travel to regional centers may be undesirable despite the expected mortality benefit. OBJECTIVE: To determine the strength of patient preferences for local care. DESIGN: Using a scenario of potentially resectable pancreatic cancer and a modification of the standard gamble utility assessment technique, we determined the level of additional operative mortality risk patients would accept to undergo surgery at a local rather than at a distant regional hospital in which operative mortality was assumed to be 3%. We used multiple logistic regression to identify predictors of willingness to accept additional risk. SUBJECTS: One hundred consecutive patients (95% male, median age 65) awaiting elective surgery at the Veterans Affairs Medical Center in White River Jct., VT. MAIN OUTCOME MEASURE: Additional operative mortality risk patients would accept to keep care local. RESULTS: All patients preferred local surgery if the operative mortality risk at the local hospital were the same as the regional hospital (3%). If local operative mortality risk were 6%, which is twice the regional risk, 45 of 100 patients would still prefer local surgery. If local risk were 12%, 23 of 100 patients would prefer local surgery. If local risk were 18%, 18 of 100 patients would prefer local surgery. Further increases in local risk did not result in large changes in the proportion of patients preferring local care. CONCLUSIONS: Many patients prefer to undergo surgery locally even when travel to a regional center would result in lower operative mortality risk. Therefore, policy makers should consider patient preferences when assessing the expected value of regionalizing major surgery.
Subject(s)
Health Services Accessibility , Hospital Mortality , Pancreatic Neoplasms/surgery , Patient Satisfaction/statistics & numerical data , Aged , Catchment Area, Health , Female , Hospital Planning , Hospitals, Veterans , Humans , Male , Pancreatic Neoplasms/mortality , Pancreatic Neoplasms/psychology , Risk Assessment , Risk Factors , Travel , VermontABSTRACT
BACKGROUND: Rates of many surgical procedures vary widely across both large and small geographic regions. Although variation in health care use has long been described, few studies have systematically compared variation profiles across surgical procedures. The goal of this study was to examine current patterns of regional variation in the rates of common surgical procedures. METHODS: The study population consisted of patients enrolled in Medicare in 1995, excluding those enrolled in risk-bearing health maintenance organizations. Patients ranged in age from 65 to 99 years. Using data from hospital discharge abstracts, we calculated rates of 11 common inpatient procedures for each of 306 US hospital referral regions (HRRs). To assess the relative variability of each procedure, we determined the number of low and high outlier regions (HRRs with rates < 50% or > 150% the national average) and the ratio of highest to lowest HRR rates. RESULTS: Procedures differed markedly in their variability. Rates of hip fracture repair, resection for colorectal cancer, and cholecystectomy varied only 1.9- to 2.9-fold across HRRs (0, 0, and 4 outlier regions, respectively). Coronary artery bypass grafting, transurethral prostatectomy, mastectomy, and total hip replacement had intermediate variation profiles, varying 3.5- to 4.7-fold across regions (8, 10, 16, and 17 outlier regions, respectively). Lower extremity revascularization, carotid endarterectomy, back surgery, and radical prostatectomy had the highest variation profiles, varying 6.5- to 10.1-fold across HRRs (25, 32, 39, and 56 outlier regions, respectively). CONCLUSIONS: Although the use of many surgical procedures varies widely across geographic areas, rates of "discretionary" procedures are most variable. To avoid potential overuse or underuse, efforts to increase consensus in clinical decision making should focus on these high variation procedures.
Subject(s)
Practice Patterns, Physicians' , Surgical Procedures, Operative/statistics & numerical data , Aged , Aged, 80 and over , Humans , Medicare , United StatesABSTRACT
BACKGROUND: With tighter constraints on health care spending, many recognize the need to identify and restrict clinical interventions that are not cost-effective. As a result, cost-effectiveness analysis is being used increasingly to assess the relative value of surgical interventions. METHODS AND RESULTS: We first present the general concept of cost-effectiveness analysis and review a recent study of carotid endarterectomy to demonstrate the technique. We next consider the classic application of cost-effectiveness analysis to resource-allocation decisions and use the Oregon Medicaid experiment to illustrate some potential problems with this approach. We then present the current role of cost-effectiveness analysis: informing decisions about individual interventions that are new, controversial, or in direct competition with an accepted alternative treatment. Finally, we review several limitations of the methods used to measure costs and benefits and discuss problems with the interpretation of cost-effectiveness studies. CONCLUSIONS: Cost-effectiveness analysis is a systematic approach to assessing the relative value of health care interventions. This technique is being used increasingly to frame clinical policy decisions in surgery. Because of this, surgeons need to understand cost-effectiveness analysis and be prepared to examine these studies critically.