Marsha M. Cohen

Mortality and reoperation after open and transurethral resection of the prostate for benign prostatic hyperplasia

As part of an ongoing effort to evaluate alternative treatments for benign prostatic hyperplasia, we compared the outcomes of transurethral resection of the prostate with those of open prostatectomy. Men undergoing prostatectomy in Denmark (n = 36,703), Oxfordshire, England (n = 5284), and Manitoba, Canada (n = 12,090), were identified retrospectively through administrative data and followed for up to eight years. The cumulative percentage of patients undergoing a second prostatectomy was substantially higher after transurethral than after open prostatectomy (12.0 vs. 4.5 percent in Denmark, 12.0 vs. 1.8 percent in Oxfordshire, and 15.5 vs. 4.2 percent in Manitoba). The long-term age-specific mortality rates associated with transurethral prostatectomy as compared with open prostatectomy were also elevated in each country. The data on 1650 Canadian patients were used to investigate the contribution of coexisting morbid conditions to the elevated risk of death. The relative risk was 1.45 (95 percent confidence interval, 1.15 to 1.83) before risk adjustment and 1.45 (95 percent confidence interval, 1.15 to 1.84) after adjustment; the higher mortality was seen among low-risk as well as high-risk patients. These findings suggest that transurethral prostatectomy is less effective in overcoming urinary obstruction than the open operation. Our data also raise the possibility that transurethral prostatectomy may result in higher long-term mortality, although we cannot rule out potential confounding effects of unmeasured characteristics of patients.

Efficacy and safety of sirolimus in lymphangioleiomyomatosis

BACKGROUND Lymphangioleiomyomatosis (LAM) is a progressive, cystic lung disease in women; it is associated with inappropriate activation of mammalian target of rapamycin (mTOR) signaling, which regulates cellular growth and lymphangiogenesis. Sirolimus (also called rapamycin) inhibits mTOR and has shown promise in phase 1-2 trials involving patients with LAM. METHODS We conducted a two-stage trial of sirolimus involving 89 patients with LAM who had moderate lung impairment--a 12-month randomized, double-blind comparison of sirolimus with placebo, followed by a 12-month observation period. The primary end point was the difference between the groups in the rate of change (slope) in forced expiratory volume in 1 second (FEV(1)). RESULTS During the treatment period, the FEV(1) slope was -12±2 ml per month in the placebo group (43 patients) and 1±2 ml per month in the sirolimus group (46 patients) (P<0.001). The absolute between-group difference in the mean change in FEV(1) during the treatment period was 153 ml, or approximately 11% of the mean FEV(1) at enrollment. As compared with the placebo group, the sirolimus group had improvement from baseline to 12 months in measures of forced vital capacity, functional residual capacity, serum vascular endothelial growth factor D (VEGF-D), and quality of life and functional performance. There was no significant between-group difference in this interval in the change in 6-minute walk distance or diffusing capacity of the lung for carbon monoxide. After discontinuation of sirolimus, the decline in lung function resumed in the sirolimus group and paralleled that in the placebo group. Adverse events were more common with sirolimus, but the frequency of serious adverse events did not differ significantly between the groups. CONCLUSIONS In patients with LAM, sirolimus stabilized lung function, reduced serum VEGF-D levels, and was associated with a reduction in symptoms and improvement in quality of life. Therapy with sirolimus may be useful in selected patients with LAM. (Funded by the National Institutes of Health and others; MILES ClinicalTrials.gov number, NCT00414648.).

Critical respiratory events in the postanesthesia care unit. Patient, surgical, and anesthetic factors.

BackgroundPrevious studies have noted a high incidence of adverse outcomes in the postanesthesia care unit (PACU), but few have examined associated factors and patient outcomes. To determine the frequency of acute, unanticipated respiratory problems and to examine the associated patient, surgical, and anesthetic factors, we prospectively collected preoperative, intraoperative, and postoperative data on 24,157 consecutive PACU patients who received a general anesthetic during a 33-month period. MethodsA PACU critical respiratory event (CRE), was defined as any unanticipated hypoxemia (hemoglobin oxygen saturation < 90%), hypoventilation (respiratory rate < 8 breaths/min or arterial carbon dioxide tension > 50 mmHg) or upper-airway obstruction (stridor or laryngospasm) requiring an active and specific intervention (ventilation, tracheal intubation, opioid or muscle relaxant antagonism, insertion of oral/nasal airway or airway manipulation). These problems were documented by PACU nurses whereas data on case-mix, surgical factors, and intraoperative management were retrieved from the anesthetic record. Significant patient, surgical, and anesthetic factors were identified by logistic regression analysis. Other morbidity experienced by patients with a CRE was also noted. ResultsFor patients given general anesthesia the risk of a CRE was 1.3% (hypoxemia 0.9%, hypoventilation 0.2%, airway obstruction 0.2%). Preoperative factors that increase risk were age > 60 yr, male gender, diabetes, and obesity (P < 0.05). Patients who underwent operative procedures on an emergency basis and whose operation was longer than 4 h were also at increased risk, but those undergoing perineal procedures were at lower risk (P < 0.05). Anesthetic risk factors (P < 0.05) included opioid premedication (relative odds 1.8), sedatives preoperatively (2.0), fentanyl> 2.0 μg.kg–1.h–1 as the sole opioid (1.9), fentanyl used in combination with morphine (1.6) and atracurium ≥ 0.25 mg.kg–1.h–1 (2.2). Patients in whom anesthesia was induced with thiopental (relative odds 2.5), compared with those who received propofol for induction, were also at increased risk of a CRE. Patients with a CRE stayed longer in PACU, had higher rates of unanticipated admissions to the intensive care unit and were more likely to have PACU cardiac problems (P < 0.01). ConclusionsA CRE is relatively rare. Multiple patient and surgical factors and specific aspects of anesthetic management are associated with the occurrence of a CRE in the PACU.

Measuring patient satisfaction with anesthesia care : A review of current methodology

I n clinical settings such as anesthesia, using patient satisfaction as an indicator to monitor the quality of clinical care has potential merit. For patients, satisfaction represents, at least in theory, an evaluation of the healthcare experience based on their own values, perceptions, and interactions with the healthcare environment. For healthcare providers, patient satisfaction can be used to assess the actual impact of healthcare processes on the patients themselves. Patients’ ratings of their satisfaction can reflect many facets of care not easily examined in any other manner: compassionate bedside skills, efficient attendance to needs, participation in decision-making, and adequate communication and information (1). An ideal measure of patient satisfaction could therefore provide unique feedback on the quality of practice for medical specialties such as anesthesia. A renewed focus has been sought for patient satisfaction as a clinical end point and a quality indicator of anesthesia care. Previous studies have demonstrated the limitations of using adverse anesthetic events to monitor anesthesia care (2). Major outcomes (death and complications such as myocardial infarction, cardiac arrest, and severe brain injury) are too rare to allow useful comparisons among institutions. Assessing minor outcomes (such as pain and nausea) pose significant methodological problems of uncertain case mix, inconsistent reporting compliance, imprecise definitions, and underand overreporting. Orkin et al. (3) emphasized the still unproven relationships between most intermediate events (for example, transient intraand postoperative hypoxemia) and clinically significant adverse events (death, myocardial infarction, etc.), as well as the difficulties in establishing those relationships. They also suggested that, in light of the

The validity of performance assessments using simulation

BackgroundThe authors wished to determine whether a simulator-based evaluation technique assessing clinical performance could demonstrate construct validity and determine the subjects’ perception of realism of the evaluation process. MethodsResearch ethics board approval and informed consent were obtained. Subjects were 33 university-based anesthesiologists, 46 community-based anesthesiologists, 23 final-year anesthesiology residents, and 37 final-year medical students. The simulation involved patient evaluation, induction, and maintenance of anesthesia. Each problem was scored as follows: no response to the problem, score = 0; compensating intervention, score = 1; and corrective treatment, score = 2. Examples of problems included atelectasis, coronary ischemia, and hypothermia. After the simulation, participants rated the realism of their experience on a 10-point visual analog scale (VAS). ResultsAfter testing for internal consistency, a seven-item scenario remained. The mean proportion scoring correct answers (out of 7) for each group was as follows: university-based anesthesiologists = 0.53, community-based anesthesiologists = 0.38, residents = 0.54, and medical students = 0.15. The overall group differences were significant (P < 0.0001). The overall realism VAS score was 7.8. There was no relation between the simulator score and the realism VAS (R = −0.07, P = 0.41). ConclusionsThe simulation-based evaluation method was able to discriminate between practice categories, demonstrating construct validity. Subjects rated the realism of the test scenario highly, suggesting that familiarity or comfort with the simulation environment had little or no effect on performance.

Predicting difficult intubation: a multivariable analysis.

Purpose: To develop a clinically useful and valid model for predicting difficult laryngoscopic tracheal intubation in patients with seemingly normal airways by adhering to the principles of multivariable model development.Methods: This was an observational study performed at a tertiary-care teaching hospital. Preoperatively, 444 randomly selected patients requiring tracheal intubation for elective surgery were assessed. In addition, 27 patients in whom tracheal intubation was difficult, but were not assessed properatively, were assessed postoperatively. One assessor, blinded to the intubation information, collected the predictor variables. A reliable definition for difficult intubation was used and all attempts were made to eliminate sources of bias. Multivariable modeling was performed using logistic regression and the model was validated using the bootstrapping technique.Results: Of the 461 patients included in the analysis, 38 were classified as difficult to intubate. Multivariable analysis identified three airway tests that were highly significant for predicting difficult tracheal intubation. These were: 1) “mouth opening”, 2) “chin protrusion”, and 3) “atlanto-occipital extension”. Using these tests, a validated, highly reliable and predictive model is produced to determine the propability of difficult intubation for patients. At a selected probability cut-off value, the model is 86.8% sensitive and 96.0% specific.Conclusion: A simple and accurate multivariable model, consisting of three airway tests, is produced for predicting difficult laryngoscopic tracheal intubation. Additional studies will be required to determine the accuracy and feasibility of this model when applied to a large sample of new patients by multiple anesthesiologists.RésuméObjectif: Élaborer un modèle valide et utilisable en clinique pour prédire des difficultés d’intubation trachéale laryngoscopique chez des patients qui ont apparemment des voies aériennes mormales. Utiliser, pour ce faire, les principes d’élaboration d’un modèle multivariable.Méthode: Il s’est agi d’une observation réalisée dans un hôpital d’enseignement de soins tertiaires. Avant l’opération, on a évalué 444 patients choisis au hasard qui avaient besoin d’intubation endotrachéale pendant une intervention planifiée. De plus, 27 patients chez qui l’intubation a été difficile n’ont été évalués qu’après l’intervention. Un assistant, qui ne connaissait pas les conditions ’intubation, a enregistré les variables de prédiction. Une définition exacte de l’intubation difficile a été utilisée et on a tenté d’éliminer tout biais possible. Une modélisation à multivariables a été réalisée en utilisant une régression logistique et le modèle a été validé par la technique de l’amore («bootstrapping»).Résultats: Des 461 patients inclus dans l’analyse, 38 ont été difficiles à intuber. L’analyse à multivariables a reconnu trois épreuves d’intubation comme hautement significatives pour prédire une intubation endotrachéale difficile: 1) «L’ouverture de la bouche», 2) «la protrusion du menton» et 3) «l’extension atlanto-occipitale». Avec ces tests, un modèle validé, très fiable et prédictif a été produit pour déterminer la probabilité d’intubation difficile. Pour une valeur limite de probabilité choisie, le modèle affichait une sensibilité de 86,8 % et une spécificité de 96,0 %.Conclusion: Un modèle à multivariables simple et précis, fait de trois test d’intubation, a été produit pour prédire des difficultés d’intubation endotrachéale laryngoscopique. D’autres études demeurent nécessaires pour évaluer la fidélité de ce modèle quand il est appliqué à un échantillon important de nouveaux patients par différents anesthésiologistes.

A multivariable model for predicting the need for blood transfusion in patients undergoing first-time elective coronary bypass graft surgery

BACKGROUND: The incidence of blood transfusion in coronary artery bypass graft (CABG) surgery remains high. Preoperative identification of those at high risk for requiring blood will allow for the cost‐effective use of some blood conservation modalities. Multivariable analysis techniques were used in this study to develop a prediction rule for such a purpose.

Who Is Most at Risk for Intimate Partner Violence?: A Canadian Population-Based Study

Whole population studies on intimate partner violence (IPV) have given contradictory information about prevalence and risk factors, especially concerning gender. The authors examined the 1999 Canadian General Social Survey data for gender patterns of physical, sexual, emotional, or financial IPV from a current or ex-partner. More women (8.6%) than men (7.0%, p = .001) reported partner physical abuse in general, physical IPV causing physical injury (p < .0001), sexual abuse (1.7% vs. 0.2%, p < .0001), and financial abuse (4.1% vs. 1.6%, p < .0001). There were no gender differences for partner emotional abuse. Significant risk factors after multivariate modeling for physical/sexual IPV were younger age, being divorced/separated or single, having children in the household, and poor self-rated physical health. These findings from a large, randomly generated data set further refine our understanding of the risk profile for IPV in the developed world.

The Ontario Uterine Fibroid Embolization Trial. Part 1. Baseline patient characteristics, fibroid burden, and impact on life ☆

OBJECTIVE To determine baseline characteristics of women undergoing uterine artery embolization (UAE) for symptomatic fibroids. DESIGN Multicenter, prospective, single-arm clinical treatment trial. SETTING Eight Ontario university and community hospitals. PATIENT(S) Five hundred fifty-five women undergoing UAE for fibroids. INTERVENTION(S) Baseline questionnaires completed before UAE. MAIN OUTCOME MEASURE(S) Questionnaires were analyzed for demographic, medical, and gynecologic histories. Fibroid symptoms, impact of symptoms, previous consultations, and treatments were also analyzed. RESULT(S) The Ontario cohort (66% white, 23% black, 11% other races) had an average age of 43. Thirty-one percent were under age 40. Most women were university educated (68%) and working outside the home (85%). Women reported heavy menstrual bleeding (80%), urinary urgency/frequency (73%), pain during intercourse (41%), and work absences (40%). They experienced fibroid-related symptoms for an average of 5 years and consulted with on average of three gynecologists before UAE. High fibroid life-impact scores were reported by 58%. Black women were significantly younger (40.7 vs. 44.0 years), more likely to experience symptoms longer (7 vs. 5 years), and more likely to undergo myomectomy before UAE (24% vs. 9%) than white women. CONCLUSION(S) Our study illustrates that large numbers of women with highly symptomatic fibroid disease are averse to surgery despite their burden of suffering and are actively seeking alternatives to hysterectomy.

Cardiovascular events in the postanesthesia care unit : Contribution of risk factors

Background The purpose of this study was to determine the relationship of four postanesthesia care unit (PACU) cardiovascular events to long-term outcomes (unplanned critical care admission or mortality) and to evaluate the contribution of anesthetic management compared with other perioperative factors in predicting these events. Methods For patients admitted to the PACU after receiving general anesthesia (n = 18,380), the risk of long-term outcomes was examined for patients in the PACU with hypertension, tachycardia, bradycardia, or hypotension. Using logistic regression (P < 0.05), risk factors (grouped as patients, surgical, anesthetic, operating room observations, and other PACU observations) for each cardiovascular event were determined. For each factor grouping, the relative contributions to each cardiovascular event were compared using maximum likelihood chi-square analysis. Results Patients in the PACU with hypertension or tachycardia had more unplanned critical care admissions (2.6% and 4.0% vs. 0.2% for patients with no events) and greater mortality (1.9% and 2.3% vs. 0.3% and 0.4%) (P < 0.01). For PACU hypertension (rate 2.0%), age, smoking, renal disease, female gender, and angina were significant risk factors. For PACU tachycardia (0.9%), intraoperative tachycardia and dysrhythmia were the major contributors. Patient factors also increased the risk of bradycardia (2.5%); namely age, ASA physical status 1 or 2, and preoperative beta blocker therapy. For hypotension (2.2%), duration of surgery > 2 h, completion after 6 PM, and gynecologic intraabdominal procedures were significant risk factors. Compared to patient, surgical, intraoperative, or PACU observations, anesthetic factors studied (premedication, induction agent, ventilation, use of opioids) provided only a small contribution in predicting these events. Conclusions Hypertension and tachycardia in the PACU, although infrequent, are associated with increased risk of unplanned critical care admission and mortality. Patient, surgical, intraoperative, or PACU observations contribute more to cardiovascular events in the PACU than do differences in anesthetic management identified in this study.