Discharge after discharge: predicting surgical site infections after patients leave hospital

In this population-based retrospective cohort study, we examined the frequency, severity, and prediction of post-discharge surgical site infections (SSIs). We evaluated all patients admitted for their first elective surgical procedure in Ontario, Canada, between 1 April 2002 and 31 March 2008. Procedure and patient characteristics were derived from linked hospital, emergency room and physician claims databases within Canada's universal healthcare system. The 30 day risk of SSI was derived from the initial hospital admission, outpatient consultations, return emergency room visits and readmissions. The cohort included 622 683 patients, of whom 84 081 (13.5%) were diagnosed with SSI, and more than half (48 725) were diagnosed post-discharge. Post-discharge infections were associated with an increased risk of reoperation (odds ratio: 2.28; 95% confidence interval: 2.11-2.48), return emergency room visit (9.08; 8.89-9.27), and readmission (6.16; 5.98-6.35). The most common risk index predicted incremental increases in the risk of in-hospital SSI, but did not predict increases in the risk of post-discharge infection. Patients with post-discharge infections had baseline characteristics more akin to uninfected patients than patients with in-hospital infections. Predictors of post-discharge infection included shorter procedure duration, shorter length of stay, rural residence, alcoholism, diabetes and obesity. Post-discharge SSIs are frequent, severe, scattered over time and location, and hard to predict using common risk indices. They represent an important hidden burden in our healthcare system.

Myocardial infarction associated with recency of immigration to Ontario

BACKGROUND

New immigrants to North America exhibit lower rates of obesity and hypertension than their native-born counterparts. Whether this is reflected by a lower relative risk of acute myocardial infarction (AMI) is not known.

OBJECTIVE

To determine the risk of AMI among new immigrants compared to long-term residents, and, among those who develop AMI, their short- and long-term mortality rate.

DESIGN

Population-based, matched, retrospective cohort study.

SETTING

Entire province of Ontario, the most populated province in Canada, from 1 April 1995 to 31 March 2007.

PARTICIPANTS

A total of 965,829 new immigrants were matched to 3,272,393 long-term residents by year of birth, sex and geographic location.

MEASUREMENTS

The main study outcome was hospitalization with a most responsible diagnosis of AMI. Secondary study outcomes among those who sustained an AMI were in-hospital, 30-day and 1-year mortality.

RESULTS

The mean age of the participants at study entry was approximately 34 years. The incidence rate of AMI was 4.14 per 10,000 person-years among new immigrants and 6.61 per 10,000 person-years among long-term residents. After adjusting for age, income quintile, urban vs. rural residence, history of hypertension, diabetes mellitus and smoking and number of health insurance claims, the hazard ratio for AMI was 0.66 [95% confidence interval (CI): 0.63-0.69].

CONCLUSION

New immigrants appear to be at lower risk of AMI than long-term residents. This finding does not appear to be explained by the availability of health-care services or income level.

Risk of premature stroke in recent immigrants (PRESARIO): population-based matched cohort study

BACKGROUND

New immigrants to North America, most of whom are under age 50 years, exhibit fewer risk factors for cardiovascular disease than their native-born counterparts, yet the stress of resettlement may conceivably place them at higher risk of stroke. We determined the risk of acute stroke associated with recency of immigration.

METHODS

We completed a population-based matched cohort study in Ontario, the largest province in Canada, from April 1, 1995, to March 31, 2007. Overall, 965,829 new immigrants were matched to 3,272,393 long-term residents by year of birth, sex, and location. New immigrants were identified as new recipients of universally available public health insurance, and long-term residents were those insured for 5 years or longer.

RESULTS

The mean age of the participants at study entry was about 34 years and the total number of observed strokes was 6,216 after a median duration of follow-up of about 6 years. The incidence rate of acute stroke was 1.69 per 10,000 person-years among new immigrants and 2.56 per 10,000 person-years among long-term residents (crude hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.62-0.71). After adjusting for age, income quintile, urban vs rural residence, history of hypertension, diabetes mellitus and smoking, and number of health insurance claims, the HR for stroke was 0.69 (95% CI 0.64-0.74). Similar risk estimates were seen for both ischemic and hemorrhagic stroke subtypes.

CONCLUSION

New immigrants appear to be at lower risk of premature acute stroke than long-term residents. This finding does not appear to be explained by the availability of health care services or income level.

The health of homeless immigrants

BACKGROUND

This study examined the association between immigrant status and current health in a representative sample of 1189 homeless people in Toronto, Canada.

METHODS

Multivariate regression analyses were performed to examine the relationship between immigrant status and current health status (assessed using the SF-12) among homeless recent immigrants (< or = 10 years since immigration), non-recent immigrants (>10 years since immigration) and Canadian-born individuals recruited at shelters and meal programmes (response rate 73%).

RESULTS

After adjusting for demographic characteristics and lifetime duration of homelessness, recent immigrants were significantly less likely to have chronic conditions (RR 0.7, 95% CI 0.5 to 0.9), mental health problems (OR 0.4, 95% CI 0.2 to 0.7), alcohol problems (OR 0.2, 95% CI 0.1 to 0.5) and drug problems (OR 0.2, 95% CI 0.1 to 0.4) than non-recent immigrants and Canadian-born individuals. Recent immigrants were also more likely to have better mental health status (+3.4 points, SE +/-1.6) and physical health status (+2.2 points, SE +/-1.3) on scales with a mean of 50 and a SD of 10 in the general population.

CONCLUSION

Homeless recent immigrants are a distinct group who are generally healthier and may have very different service needs from other homeless people.

The impact of home nocturnal hemodialysis on end-stage renal disease therapies: a decision analysis

Home nocturnal hemodialysis (HNHD) is cost-effective relative to in-center hemodialysis (IHD) in short-run analyses. The effect in long-run analyses, when technique failures, declining benefits, delayed training, transplantation and death are considered, is unknown. We used decision analysis techniques to examine the relative cost-effectiveness of HNHD and IHD, projecting future costs and health effects over a lifetime with end-stage renal disease. We developed a Markov state-transition model comparing two strategies: only IHD or starting on IHD and subsequently transferring to HNHD. The model incorporates transplantation. In the base case, half the population was eligible for transplantation, with (1/3) of grafts from live donors. The time to transplant was 0.75 years for live and 5 years for deceased donor transplants. The delay before initiation of HNHD was 5 years. Costs and outcomes were discounted at 3% per annum. Model parameters were derived from a literature review. We also conducted one-way sensitivity analyses and Monte Carlo simulations. The HNHD strategy was associated with a quality-adjusted survival estimate of 5.79 quality-adjusted life years (QALYs), with lifetime costs of $538 094. The values for IHD were 5.31 QALYs and $543 602, respectively. Thus, HNHD is cost saving while improving quality of life. The incremental cost-utility ratio was consistently less than $50 000 per QALY in sensitivity and Monte Carlo analyses. Important determinants of cost-effectiveness were transplantation time and whether benefits declined over time. Our model suggests that HNHD improves quality-adjusted survival over IHD at an economically attractive cost-effectiveness ratio.

Assessing damage in individual joints in rheumatoid arthritis: a new method based on the Larsen system

OBJECTIVES

To evaluate observer agreement using the Larsen system (LS) and a Modified Larsen system (ML) when assessing individual joints of the hands and wrists in rheumatoid arthritis, and to compare the two systems. To determine the minimally important difference (MID) for the ML.

METHODS

Thirty radiographs of hands and wrists from 10 patients who presented with RA were graded by two blinded observers, using the LS and then the ML. Patients were followed for a mean of 7.2 years (range: 4-10 years). Inter- and intra-observer agreement were calculated using the kappa statistic with linear incremental weights. Inter-observer agreement was also computed for the summed score, using an intraclass correlation coefficient. Inter-observer error was estimated by calculating the mean and standard deviation of the grading differences between the two observers. Prevalence of damage was calculated as a ratio of damage: no damage and expressed as a percentage. Pairs of radiographs were comparatively graded using a seven-point Likert scale.

RESULTS

The kappa statistic for inter-observer agreement was 0.38 (marginal reproducibility) for the LS and 0.52 (good reproducibility) for the ML (P = 0.004). Using a difference of one grade as perfect agreement, it was 0.56 (good reproducibility) for the LS and 0.87 (excellent reproducibility) for the ML (P = 0.001). Intra-observer agreement was high in both systems. The distribution of ML-grade differences varied according to the level of the Likert scale: for "a little bit worse", representing the smallest amount of detectable damage progression, the distribution differences peaked around two grades. This value represented a MID 87% of the time.

CONCLUSIONS

The LS lacks precision for individual joints. The ML, it is proposed, has more detailed definitions of grades, and is more reliable. When pairs of radiographs were compared, a two-grade difference on the ML was the MID.

Longevity of screenwriters who win an academy award: longitudinal study

OBJECTIVE

To determine whether the link between high success and longevity extends to academy award winning screenwriters.

DESIGN

Retrospective cohort analysis.

PARTICIPANTS

All screenwriters ever nominated for an academy award.

MAIN OUTCOME MEASURES

Life expectancy and all cause mortality.

RESULTS

A total of 850 writers were nominated; the median duration of follow up from birth was 68 years; and 428 writers died. On average, winners were more successful than nominees, as indicated by a 14% longer career (27.7 v 24.2, P=0.004), 34% more total films (23.2 v 17.3, P<0.001), 58% more four star films (4.8 v 3.1, P<0.001), and 62% more nominations (2.1 v 1.3, P<0.001). However, life expectancy was 3.6 years shorter for winners than for nominees (74.1 v 77.7 years, P=0.004), equivalent to a 37% relative increase in death rates (95% confidence interval 10 to 70). After adjustment for year of birth, sex, and other factors, a 35% relative increase in death rates was found (7% to 70%). Additional wins were associated with a 22% relative increase in death rates (3% to 44%). Additional nominations and additional other films in a career otherwise caused no significant increase in death rates.

CONCLUSION

The link between occupational achievement and longevity is reversed in screenwriters who win academy awards. Doubt is cast on simple biological theories for the survival gradients found for other members of society.

Emergency department overcrowding following systematic hospital restructuring: trends at twenty hospitals over ten years

OBJECTIVE

Hospital restructuring often results in fewer inpatient beds, increased ambulatory services, and closures of hospitals or emergency departments (EDs). The authors sought to determine the impact of systematic hospital restructuring on ED overcrowding.

METHODS

Time series analyses of average monthly overcrowding for EDs in Toronto, Ontario, Canada, from 1991 and 2000 (n = 20 hospitals, 120 months) were conducted. Autoregression models evaluated the rate of increase of overcrowding before and during systematic restructuring. A secondary analysis included total ED visits, patient age, and sex distribution as covariates. Seasonality was assessed by means of spectral analysis.

RESULTS

Severe and moderate overcrowding averaged 3% and 14% of the time each month, respectively, over the whole period. Before restructuring (n = 74 months), severe and moderate overcrowding averaged 0.5% and 9% per month, respectively; during restructuring (n = 46 months), the monthly averages were 6% and 23%, respectively. Neither severe nor moderate overcrowding was increasing before restructuring. During restructuring, however, both increased significantly (severe 0.2% per month [p < 0.0001]; moderate 0.5% per month [p < 0.0001]). Similar results were found after controlling for ED utilization. Female gender independently predicted increased overcrowding; older age predicted reduced moderate overcrowding; number of total visits was not a predictor. Spectral analysis revealed significant seasonality in overcrowding.

CONCLUSIONS

Hospital restructuring was associated with increased ED overcrowding, even after controlling for utilization and patient demographics. Restructuring should proceed slowly to allow time for monitoring of its effects and modification of the process, because the impact of incremental reductions in hospital resources may be magnified as maximum operating capacity is approached.

The beguiling pursuit of more information

BACKGROUND

The authors tested whether clinicians make different decisions if they pursue information than if they receive the same information from the start.

METHODS

Three groups of clinicians participated (N=1206): dialysis nurses (n=171), practicing urologists (n=461), and academic physicians (n=574). Surveys were sent to each group containing medical scenarios formulated in 1 of 2 versions. The simple version of each scenario presented a choice between 2 options. The search version presented the same choice but only after some information had been missing and subsequently obtained. The 2 versions otherwise contained identical data and were randomly assigned.

RESULTS

In one scenario involving a personal choice about kidney donation, more dialysis nurses were willing to donate when they first decided to be tested for compatibility and were found suitable than when theyknew they were suitable from the start (65% vs. 44%, P= 0.007). Similar discrepancies were found in decisions made by practicing urologists concerning surgery for a patient with prostate cancer and in decisions of academic physicians considering emergency management for a patient with acute chest pain.

CONCLUSIONS

The pursuit of information can increase its salience and cause clinicians to assign more importance to the information than if the same information was immediately available. An awareness of this cognitive bias may lead to improved decision making in difficult medical situations.

Mortality among patients admitted to hospitals on weekends as compared with weekdays

BACKGROUND

The level of staffing in hospitals is often lower on weekends than on weekdays, despite a presumably consistent day-to-day burden of disease. It is uncertain whether in-hospital mortality rates among patients with serious conditions differ according to whether they are admitted on a weekend or on a weekday.

METHODS

We analyzed all acute care admissions from emergency departments in Ontario, Canada, between 1988 and 1997 (a total of 3,789,917 admissions). We compared in-hospital mortality among patients admitted on a weekend with that among patients admitted on a weekday for three prespecified diseases: ruptured abdominal aortic aneurysm (5454 admissions), acute epiglottitis (1139), and pulmonary embolism (11,686) and for three control diseases: myocardial infarction (160,220), intracerebral hemorrhage (10,987), and acute hip fracture (59,670), as well as for the 100 conditions that were the most common causes of death (accounting for 1,820,885 admissions).

RESULTS

Weekend admissions were associated with significantly higher in-hospital mortality rates than were weekday admissions among patients with ruptured abdominal aortic aneurysms (42 percent vs. 36 percent, P<0.001), acute epiglottitis (1.7 percent vs. 0.3 percent, P=0.04), and pulmonary embolism (13 percent vs. 11 percent, P=0.009). The differences in mortality persisted for all three diagnoses after adjustment for age, sex, and coexisting disorders. There were no significant differences in mortality between weekday and weekend admissions for the three control diagnoses. Weekend admissions were also associated with significantly higher mortality rates for 23 of the 100 leading causes of death and were not associated with significantly lower mortality rates for any of these conditions.

CONCLUSIONS

Patients with some serious medical conditions are more likely to die in the hospital if they are admitted on a weekend than if they are admitted on a weekday.

Availability of antidotes at acute care hospitals in Ontario

BACKGROUND

Acutely poisoned patients sometimes require immediate treatment with an antidote, and delays in treatment can be fatal. We sought to determine the availability of 10 antidotes at acute care hospitals in Ontario.

METHODS

Mailed questionnaire with repeated reminders to pharmacy directors at all acute care hospitals in Ontario.

RESULTS

Responses were obtained from 179 (97%) of 184 hospitals. Only 9% of the hospitals stocked an adequate supply of digoxin immune Fab antibody fragments, a life-saving antidote for patients with severe digoxin toxicity, whereas most of the hospitals stocked sufficient supplies of ipecac syrup (88%) and flumazenil (92%), arguably the least crucial antidotes in the survey. Only 1 hospital stocked adequate amounts of all 10 antidotes. Certain hospital characteristics were associated with adequate antidote stocking (increased annual emergency department volume, teaching hospital status and designation as a trauma centre). Conversely, antidote supplies were particularly deficient at small hospitals and, paradoxically, geographically isolated facilities (those most reliant on their own inventory). The cost of antidotes correlated only weakly with stocking rates, and many examples of excessive antidote stocking were identified.

INTERPRETATION

Most acute care hospitals in Ontario do not stock even minimally adequate amounts of several emergency antidotes, possibly jeopardizing the survival of an acutely poisoned patient. Much of this problem could be rectified at no additional cost by reducing excessive stock of expensive antidotes and redistributing the resources to acquire deficient antidotes.

Problems for clinical judgement: 4. Surviving in the report card era

Health care report cards involve comparisons of health care systems, hospitals or clinicians on performance measures. They are going to be an important feature of medical care in Canada in the new millennium as patients demand more information about their medical care. Although many clinicians are aware of this growing trend, they may not be prepared for all of its implications. In this article, we provide some historical background on health care report cards and describe a number of strategies to help clinicians survive and thrive in the report card era. We offer a number of tips ranging from knowing your outcomes first to proactively getting involved in developing report cards.

Survival in Academy Award-winning actors and actresses

BACKGROUND

Social status is an important predictor of poor health. Most studies of this issue have focused on the lower echelons of society.

OBJECTIVE

To determine whether the increase in status from winning an academy award is associated with long-term mortality among actors and actresses.

DESIGN

Retrospective cohort analysis.

SETTING

Academy of Motion Picture Arts and Sciences.

PARTICIPANTS

All actors and actresses ever nominated for an academy award in a leading or a supporting role were identified (n = 762). For each, another cast member of the same sex who was in the same film and was born in the same era was identified (n = 887).

MEASUREMENTS

Life expectancy and all-cause mortality rates.

RESULTS

All 1649 performers were analyzed; the median duration of follow-up time from birth was 66 years, and 772 deaths occurred (primarily from ischemic heart disease and malignant disease). Life expectancy was 3.9 years longer for Academy Award winners than for other, less recognized performers (79.7 vs. 75.8 years; P = 0.003). This difference was equal to a 28% relative reduction in death rates (95% CI, 10% to 42%). Adjustment for birth year, sex, and ethnicity yielded similar results, as did adjustments for birth country, possible name change, age at release of first film, and total films in career. Additional wins were associated with a 22% relative reduction in death rates (CI, 5% to 35%), whereas additional films and additional nominations were not associated with a significant reduction in death rates.

CONCLUSION

The association of high status with increased longevity that prevails in the public also extends to celebrities, contributes to a large survival advantage, and is partially explained by factors related to success.

Problems for clinical judgement: 3. Thinking clearly in an emergency

The resuscitation of a patient in extremis is frequently characterized by chaos and disorganization, and is one of the most stressful situations in medicine. We reviewed selected studies from the fields of anesthesia, emergency medicine and critical care that address the process of responding to a critically ill patient. Individual clinicians can improve their performance by increased exposure to emergencies during training and by the incorporation of teamwork, communication and crisis resource management principles into existing critical care courses. Team performance may be enhanced by assessing personality factors when selecting personnel for high-stress areas, explicit assignment of roles, ensuring a common "culture" in the team and routine debriefings. Over-reliance on technology and instinct at the expense of systematic responses should be avoided. Better training and teamwork may allow for clearer thinking in emergencies, so that knowledge can be translated into effective action and better patient outcomes.

Major trauma in elderly adults receiving lipid-lowering medications

BACKGROUND

Some clinical trials, laboratory experiments, and in vitro studies suggest that lipid-lowering medications predispose a person to traumatic injury.

METHODS

We used population-based administrative database analysis to study adults age 65 years or more over a 5-year interval (n = 1,348,259).

RESULTS

About 12% of the cohort received a prescription for a lipid-lowering medication and about 88% did not. The two groups had similar distributions of age, gender, and income. Overall, 2,557 (0.2%) were hospitalized for major trauma. Those who received a lipid-lowering medication were 39% less likely to sustain a major trauma than those who did not receive such medication (95% confidence interval, 29 to 47). Similar results were observed after adjustment for age, gender, and income; cardiac and neurologic medications; and lethality. No other cardiac or neurologic medication was associated with an apparent safety advantage.

CONCLUSION

Lipid-lowering medications do not lead to a clinically important increase in the absolute risk of major trauma for elderly patients in the community.

Problems for clinical judgement: 2. Obtaining a reliable past medical history

Ordinary human reasoning may lead patients to provide an unreliable history of past experiences because of errors in comprehension, recall, evaluation and expression. Comprehension of a question may change depending on the definition of periods of time and prior questions. Recall fails through the loss of relevant information, the fabrication of misinformation and distracting cues. Evaluations may be mistaken because of the "halo effect" and a reluctance to change personal beliefs. Expression is influenced by social culture and the environment. These errors can also occur when patients report a history of present illness, but they tend to be more prominent with experiences that are more remote. An awareness of these specific human fallibilities might help clinicians avoid some errors when eliciting a patient's past medical history.

Problems for clinical judgement: 1. Eliciting an insightful history of present illness

This article presents the results of a review of studies of psychology that describe how ordinary human reasoning may lead patients to provide an unreliable history of present illness. Patients make errors because of mistakes in comprehension, recall, evaluation and expression. Comprehension of a question changes depending on ambiguities in the language used and conversational norms. Recall fails through the forgetting of relevant information and through automatic shortcuts to memory. Evaluation can be mistaken because of shifting social comparisons and faulty personal beliefs. Expression is influenced by moods and ignoble failures. We suggest that an awareness of how people report current symptoms and events is an important clinical skill that can be enhanced by knowledge of selected studies in psychology. These insights might help clinicians avoid mistakes when eliciting a patient's history of present illness.

Microalbuminuria screening for patients having type 2 diabetes mellitus: who wants to participate?

BACKGROUND AND OBJECTIVES

"Difficult-to-recruit" patients are sometimes less compliant with their care, are more reluctant to seek medical attention and less likely to survive than their "easy-to-recruit" counterparts. They also tend to be excluded from clinical trials. The aim of this paper was to evaluate whether such differences extend to patients' willingness to be screened for diabetic nephropathy in a family practice setting.

DESIGN

A cross-sectional study.

SETTING

A Canadian university family practice unit.

PATIENTS

Two hundred and forty-seven patients with type 2 (adult-onset) diabetes mellitus as identified by computer searches of patient records of approximately 12,000 patients in the family practice unit.

INTERVENTION

A cross-sectional secondary preventive screening program obtained urine samples from all patients with type 2 diabetes mellitus, regardless of patients' willingness to participate.

MAIN OUTCOME MEASURE

The prevalence of micro- and macroalbuminuria.

RESULTS

Of the 247 patients identified, 186 (75%) easy-to-recruit enrollees agreed to participate in screening and 61 (25%) difficult-to-recruit non-enrollees initially declined to be screened. The non-enrollees were subsequently evaluated by their own family physicians as part of routine clinical care and the results were captured for analysis. Overall rates of albuminuria were similar in the easy- and difficult-to-recruit groups (31% versus 38%, p = 0.151). The main predictors of albuminuria were female sex (odds ratio [OR] = 2.1, p = 0.021), duration of diabetes in years (OR = 1.05, p = 0.023), current use of angiotensin-converting enzyme inhibitor (OR = 2.26, p = 0.008) and number of diabetic complications (OR = 1.45, p = 0.028).

CONCLUSIONS

There is little difference in the prevalence of albuminuria related to patients' willingness to participate in a screening program. Therefore, there are no disproportionate gains for family practice researchers who aggressively seek difficult-to-recruit patients in this set ting. In contrast, primary care doctors should make every effort to ensure optimal care to diabetic patients regardless of a patient's initial hesitancy.

How to read clinical journals: X. How to react when your colleagues haven't read a thing

Physicians receive little instruction on how to interact with colleagues, and even less guidance on what to do when their colleagues are poorly informed. Eight techniques are presented here that may be of use in dealing with colleagues who have clearly not read the literature and are unable to maintain the facade that they have. If employed properly and used judiciously, these techniques may help avoid embarrassment for all and may also improve the exchange of valuable information between professionals.

Carotid endarterectomy for women and men

Carotid endarterectomy is the standard of care for people with severe symptomatic carotid stenosis. We analyzed population administrative data and clinical trial data to determine whether sex differences exist in the use and outcomes of this surgical procedure. We studied patients in Ontario who underwent carotid endarterectomy between 1982 and 1994 (n = 12,949) and patients with severe carotid stenosis who were enrolled in two randomized trials of endarterectomy (n = 1646). We compared the proportion of men and women who underwent carotid endarterectomy in each group, over time, and after adjustment for demographic factors. Men were twice as likely as women to receive carotid endarterectomy in the administrative analysis (65% versus 35%, p < 0.001) and in the clinical trial analysis (70% versus 30%, p < 0.001). The relatively lower use in women was consistent in every age group and in every year studied. Men in the administrative database were somewhat less likely than women to die or be institutionalized after surgery (5% versus 6%, p = 0.007). Men in the clinical trial database were also less likely than women to experience perioperative stroke or death, although the results were not statistically significant (6% versus 7%, p = 0.32). Patients who were assigned to surgical therapy, compared with those assigned to medical therapy, had a significant decrease in the risk of adverse events at 1 year, and the net benefit appeared similar in women and men. Carotid endarterectomy is performed relatively infrequently on women despite their similar lifetime burden of disease and similar short-term perioperative risks compared with men.

Decision analysis with cumulative prospect theory

BACKGROUND

Individuals sometimes express preferences that do not follow expected utility theory. Cumulative prospect theory adjusts for some phenomena by using decision weights rather than probabilities when analyzing a decision tree.

METHODS

The authors examined how probability transformations from cumulative prospect theory might alter a decision analysis of a prophylactic therapy in AIDS, eliciting utilities from patients with HIV infection (n = 75) and calculating expected outcomes using an established Markov model. They next focused on transformations of three sets of probabilities: 1) the probabilities used in calculating standard-gamble utility scores; 2) the probabilities of being in discrete Markov states; 3) the probabilities of transitioning between Markov states.

RESULTS

The same prophylaxis strategy yielded the highest quality-adjusted survival under all transformations. For the average patient, prophylaxis appeared relatively less advantageous when standard-gamble utilities were transformed. Prophylaxis appeared relatively more advantageous when state probabilities were transformed and relatively less advantageous when transition probabilities were transformed. Transforming standard-gamble and transition probabilities simultaneously decreased the gain from prophylaxis by almost half. Sensitivity analysis indicated that even near-linear probability weighting transformations could substantially alter quality-adjusted survival estimates.

CONCLUSION

The magnitude of benefit estimated in a decision-analytic model can change significantly after using cumulative prospect theory. Incorporating cumulative prospect theory into decision analysis can provide a form of sensitivity analysis and may help describe when people deviate from expected utility theory.

Quality of life and utility in irradiated laryngeal cancer patients

PURPOSE

To determine quality of life (QOL) and health utility in irradiated laryngeal cancer survivors.

MATERIALS AND METHODS

Over 6 months, consecutive follow-up patients at a comprehensive cancer centre completed the QOL questionnaire FACT-H&N and the time trade-off (TTO) utility instrument.

RESULTS

Inclusion criteria were met by 339 patients, of whom 269 were eligible, 245 were approached, and 120 agreed to participate. Most participants were men (83%) who had received radiotherapy (97%) for Stage I disease (53%) of the glottis (75%); 7% had undergone total laryngectomy. Participants differed from nonparticipants only in being younger (mean age, 65 vs. 68 years, p = 0.0049) and having higher performance status (Karnofsky 88 vs. 84, p = 0.0012). The average scores for FACT-H&N and the TTO were 124/144 (SD, 14) and 0.90/1.0 (SD, 0.16) respectively. FACT-H&N score was more highly correlated with Karnofsky score (r = 0.43, p = 0.001) than with the TTO (r = 0.29, p = 0.002). Gender predicted QOL (means: M = 125, F = 118), while natural speech, no relapses, and more time since initial treatment predicted higher utility.

CONCLUSION

The QOL of irradiated laryngeal cancer survivors was reasonably high and independent of initial disease variables. The QOL questionnaire correlated more strongly with performance status than with utility, suggesting that QOL and utility measures may be perceived differently by patients.

Continuous electrocardiographic monitoring and cardiac arrest outcomes in 8,932 telemetry ward patients

OBJECTIVE

To estimate the benefit of routine electrocardiographic (ECG) telemetry monitoring on in-hospital cardiac arrest survival.

METHODS

In a tertiary care hospital, all telemetry ward admissions and cardiac arrests occurring over a five-year period were reviewed. Ward location and survival to discharge were determined for all patients outside of critical care areas.

RESULTS

During the study period, 8,932 patients were admitted to the telemetry ward, and 20 suffered cardiac arrest (0.2%; 95% CI = 0.1 to 0.3). Telemetry monitors signaled the onset of cardiac arrest in only 56% (95% CI = 30 to 80) of monitored arrests. Three patients survived to discharge, and in two of these three patients the arrest onset was signaled by the monitor. This yields a monitor-signaled survival rate among telemetry ward patients of 0.02% (95% CI = 0 to 0.05). All survivors suffered significant arrhythmias prior to their cardiac arrests.

CONCLUSIONS

Cardiac arrest is an uncommon event among telemetry ward patients, and monitor-signaled survivors are extremely rare. Routine telemetry offers little cardiac arrest survival benefit to most monitored patients, and a more selective policy for telemetry use might safely avoid ECG monitoring for many patients.

Charges for medical care at different hospitals

BACKGROUND

The United States has a high proportion of people without health insurance (15%) and a low proportion of people without employment (5%), resulting in millions who lack insurance but have some ability to pay. We tested whether hospitals charge similar prices for well-specified elective services to individuals paying out-of-pocket for medical care.

METHODS

We surveyed the 2 largest general hospitals from every large city (population >500 000) in the United States and Canada. At each hospital we evaluated 5 diagnostic, 7 therapeutic, and 3 nonclinical services to determine the total charge to patients who pay directly.

RESULTS

Overall, 66 hospitals were included (average, 758 beds; not-for-profit, 97% [n = 64]; teaching, 80% [n = 53]). The range in charges was substantial; for example, a screening mammogram was $40 at one hospital in Los Angeles, Calif, and $346 at one hospital in Quebec City. Charges for a screening mammogram were relatively stable between 1996 and 1997 (r=0.79; 95% confidence interval, 0.68-0.87) and unrelated to the hospital's location or charges for other services. The relative amount of variation in charges was similar for high-priced and low-priced services, similar for diagnostic and therapeutic services, and similar for the United States and Canada.

CONCLUSIONS

Charges for the same hospital service vary substantially. Greater visibility might reduce some variation by bringing outliers into closer scrutiny. Patients seeking care and paying out-of-pocket could save financially by comparison shopping.

Effects of trauma cases on the care of patients who have chest pain in an emergency department

BACKGROUND

Trauma victims sometimes take priority over other patients because their injuries require immediate treatment. We examined whether such demands might compromise the care of patients with acute chest pain in an emergency department.

METHODS

Case patients were patients with chest pain who arrived immediately after a major trauma victim. Control patients were patients with chest pain who arrived on a preceding day when no trauma patient was in the emergency department.

RESULTS

Case and control patients were similar in mean age (60 vs. 60 years, p = not significant), percentage male (47 vs. 53%, p = not significant) and percentage ultimately diagnosed as cardiac (29 vs. 33%, p = not significant). Case patients spent an average of 81 minutes longer in the emergency department (297 vs. 216 minutes, p = 0.009). Similar delays were observed in the subgroup of patients ultimately diagnosed as cardiac (309 vs. 217 minutes, p = 0.029). Case patients had generally worse scores on the American College of Emergency Physicians Quality Assurance Index (75.6 vs. 84.4, p = 0.027), particularly those ultimately diagnosed as cardiac (60.3 vs. 85.1, p = 0.002). The common failures were failure to administer aspirin, undertreatment of ongoing pain, and failure to provide instructions regarding treatment and need to return.

CONCLUSION

Trauma victims can decrease the timeliness and quality of care for other patients who have potentially life-threatening conditions in an emergency department.

Comparison of molecular and conventional strategies for followup of superficial bladder cancer using decision analysis

PURPOSE

Patients with superficial bladder cancer require long-term surveillance for recurrence. We compared the cost of cystoscopy and cytology (standard care) to that of urinary markers (modified care) for patients with a history of superficial bladder cancer.

MATERIALS AND METHODS

We constructed a decision analysis model that compared the 2 strategies for a hypothetical followup interval of 3 years. Probabilities required for the decision tree were based on a cohort of 361 patients diagnosed with superficial bladder cancer from 1987 to 1997. Sensitivity analyses were used to determine whether test sensitivity and specificity would affect cost thresholds. Costs for each strategy were then applied to actual practice patterns.

RESULTS

The cost of modified care ranged from $158 to $228 for each followup visit when using a urinary marker with a sensitivity and specificity of 95% and 77%, respectively. The cost of standard care was $240 for each followup visit. Based on sensitivity analyses the probability of disease recurrence and urinary marker accuracy were important determinants of expected costs. Mean number of followup assessments for patients followed more than 3 years was 4.3, 2.2 and 1.5 for years 1, 2 and 3, respectively. Cumulative costs of modified care were lower than those of standard care.

CONCLUSIONS

Urinary marker testing for followup of patients with superficial bladder cancer is less expensive than the standard method of cystoscopy and urinary cytology based on our model. Future studies will be required to consider other factors that could affect the cost advantage of urinary markers, including indirect costs, the psychosocial impact of testing and different surveillance frequencies.

Diffuse pulmonary arteriovenous malformations: characteristics and prognosis

OBJECTIVE

To study the clinical characteristics and prognosis of patients with diffuse pulmonary arteriovenous malformations (AVMs).

DESIGN

Retrospective chart review of all patients (n = 16) with diffuse pulmonary AVMs seen at Yale New Haven Hospital, Johns Hopkins Hospital, and St. Michael's Hospital. Up-to-date follow-up information was obtained in all living patients.

RESULTS

All patients were severely hypoxic. Neurologic complications (stroke or brain abscess) had occurred in 70% of patients by the time of diagnosis. During the follow-up period (mean, 6 years), three patients died and two others developed new neurologic complications. One of the deaths occurred perioperatively during lung transplantation. All patients underwent transcatheter embolotherapy of any large pulmonary AVMs. A selected group underwent pulmonary flow redistribution, a novel technique. Oxygenation did not improve significantly with embolotherapy of the larger AVMs, but there was a small significant improvement in those patients who underwent pulmonary flow redistribution. The majority (85%) of the living patients are currently working or studying full-time.

CONCLUSIONS

Patients with diffuse pulmonary AVMs are at increased risk of neurologic complications. Transcatheter embolotherapy does not significantly improve the profound hypoxia, but it may reduce the risk of neurologic complications. Antibiotic prophylaxis is recommended for bacteremic procedures to prevent brain abscess. These patients can live for many years and lead productive lives. We do not recommend lung transplantation because survival with disease is difficult to predict and we have observed a perioperative transplant death.

Economic methods for measuring the quality of life associated with HIV infection

BACKGROUND

Quality of life is measured as utilities for cost-effectiveness analyses.

OBJECTIVE

To test the adequacy of three common utility elicitation methods for individuals with Human Immunodeficiency Virus (HIV) disease.

MEASUREMENTS

HIV-positive participants (n = 75) rated three standardized health states (symptomatic HIV infection, minor AIDS defining illness, and major AIDS defining illness) with two utility elicitation methods (Standard Gamble [SG], and Time Trade-off [TTO]) and one value method (Visual Analog [VA]). Participants also rated their own health with one utility method (Health Utilities Index [HUI]) and one conventional quality of life method (Medical Outcomes Study--HIV Health Survey [MOS-HIV]).

RESULTS

For all states, SG and TTO scores ranged from near 0.00 (equivalent to death) to 1.00 (best possible quality of life). Mean scores for symptomatic HIV were similar with the SG (0.80) and TTO (0.81) but higher than with the VA (0.70). Similar results were observed for minor AIDS defining illnesses (0.65, 0.65, 0.46 respectively) and major AIDS defining illnesses (0.42, 0.44, 0.25 respectively). Discrepant SG and TTO scores were observed in many individuals and were not explained by demographic characteristics. As expected, HUI scores of an individual's own health were related to the disease state. Four of ten MOS-HIV subscales (overall health, physical functioning, role functioning, and pain) were also related to disease state. HUI scores were correlated with the MOS-HIV score for overall health and for all MOS-HIV subscales except health transition.

CONCLUSIONS

Mean utility scores for HIV-related health states elicited by the Standard Gamble and Time Trade-off were similar but a large degree of individual variation persists. Economic methods provide imprecise estimates of the quality of life associated with HIV infection.

Adhesive tape and intravascular-catheter-associated infections

Adhesive tape is placed in close contact with intravascular catheters for extended periods and could theoretically contribute to local infections. We found that 74% of specimens of tape collected in one hospital were colonized by pathogenic bacteria. However, only 5% of specimens had significant growth from an inner layer obtained by discarding the outside layer from each roll. We suggest that adhesive tape is a potential source of pathogenic bacteria and that discarding the outer layer from a partially used roll might be a simple method for reducing the risk of infection to patients.

Electromotive drug administration of lidocaine as an alternative anesthesia for transurethral surgery

PURPOSE

A multicenter study was undertaken to evaluate the safety, efficacy and cost of electromotive drug administration of intravesical lidocaine to produce bladder local anesthesia as an alternative to traditional methods of spinal or general anesthesia.

MATERIALS AND METHODS

A total of 94 patients were enrolled in the study who had either a history of bladder tumor that required cold cup bladder biopsy with fulguration for possible recurrence as a comparison trial, a bladder tumor treated with transurethral resection/fulguration or benign prostatic hyperplasia/carcinoma treated with transurethral resection. Pain scores using a Verbal Rating Scale were recorded for each individual biopsy, fulguration and resection event. Data for direct and indirect costs were collected using a standardized form for each patient to capture the details of the procedure, including times, drugs and disposables for each patient.

RESULTS

There was a significant reduction in pain for patients who received electromotive intravesical lidocaine compared to no anesthesia for biopsy (p<0.03). Similarly, electromotive intravesical lidocaine for bladder biopsy and transurethral bladder tumor resection/fulguration was associated with higher patient satisfaction compared to previous treatments (p<0.00002). In contrast, electromotive intravesical lidocaine was insufficient for 3 of 6 transurethral prostatic resections. The cost per patient was about $146 Cdn less with electromotive intravesical lidocaine than with conventional general/spinal anesthesia.

CONCLUSIONS

Electromotive intravesical lidocaine may be a safe, effective and affordable form of anesthesia for the ambulatory care of patients requiring transurethral bladder biopsy, resection or fulguration with a potential for cost savings.

Cost-effectiveness of regulations against using a cellular telephone while driving

PURPOSE

To evaluate the cost-effectiveness of regulations that prohibit using a cellular telephone while driving a motor vehicle.

DESIGN

Decision analysis of risks and benefits related to cellular telephones and driving.

SETTING

United States population in 1997.

MEASURES

Health benefits measured as the quality-adjusted life years potentially saved. Financial benefits measured as health care and other services potentially averted. Costs of regulation measured as the lost productivity derived from willingness to pay for cellular telephone calls.

RESULTS

Under base-case conditions, cellular telephone calls in the United States each day accounted for about 984 reported collisions, 1,729 total collisions, 2 deaths, 317 persons with injuries, 99 lost years of life expectancy, 161 lost quality-adjusted life years, $1 million in health care costs, and $4 million in property damage and other costs. This reflected a total of about 35 million telephone calls while driving, 70 million calling minutes, and $33 million in total value to society. The estimated cost-effectiveness ratio for a regulation restricting cellular telephone usage while driving was $300,000 per quality-adjusted life year saved, but ranged from $50,000 to $700,000 under alternative assumptions and interpretations of data. Regulations applied to teenage males could be cost-saving to society if the value of a call fell below 37 cents per minute.

CONCLUSIONS

Regulations restricting cellular telephone usage while driving are less cost-effective for society than other safety measures. Nevertheless, regulations may be justifiable because the benefits and harms do not always involve the individual who has the cellular telephone. Increasing the price of a call (or adding a supplementary tax) might decrease the number of discretionary calls, be cost-saving for society, and be life-saving for individuals.