Canadian guidelines for cardiac rehabilitation and atherosclerotic heart disease prevention: a summary.

Atherosclerotic heart disease (AHD) is the leading cause of death in Canadian women and men. Cardiac rehabilitation has been repeatedly shown to reduce cardiac morbidity and mortality significantly among patients with documented AHD. The Canadian Association of Cardiac Rehabilitation (CACR) has defined cardiac rehabilitation as "the enhancement and maintenance of cardiovascular health through individualized programs designed to optimize physical, psychological, social, vocational and emotional status. This process includes the facilitation and delivery of secondary prevention through heart hazard (risk factor) identification and modification in an effort to prevent disease progression and the recurrence of cardiac events". This summary presents a limited amount of background information and the majority of clinical practice recommendations contained within the previously published CACR Guidelines. These evidence-based clinical recommendations are intended as guidelines to good clinical practice rather than as standards of care. The key focus of this summary is the need for complete and targeted intervention of all heart hazards in patients at high or very high risk for, or with documented, AHD. To achieve this goal, the CACR Guidelines and this summary present risk stratification strategies designed to determine unambiguously a patient's risk of exercise-related cardiac events (short term absolute risk or disease prognosis) and their risk of recurrent AHD events (long term absolute risk from disease progression). The establishment of the short term and long term absolute AHD risks can then be used to determine heart hazard targets and the type of exercise program prescribed for patients with AHD. Despite the use of evidence-based medical practices, none of the recommendations presented in this document can replace the expert judgment of properly trained and experienced cardiac rehabilitation professionals. Health care providers must always be free to choose where and when clinical practice guidelines are applied, modified or superceded, depending on individual patient circumstances.

Infants undergoing pyloromyotomy are not at risk for postoperative apnea. Staff of Sutter Community Hospitals Sleep Disorders Center.

Thirty term infants undergoing general anesthesia and pyloromyotomy had pre- and postoperative sleep studies to determine whether these infants were at risk for postoperative apnea. Sleep studies showed an improved respiratory disturbance index (RDI) after surgery. Postoperatively, apnea indices were lower and lowest oxygen saturation values were increased compared to the infants' preoperative status. We conclude that pyloromyotomy does not elicit postoperative apnea in term infants.

Tracheal extubation of children in the operating room after atrial septal defect repair as part of a clinical practice guideline.

Early tracheal extubation in the operating room after atrial septal defect (ASD) surgery was recommended as part of a clinical practice guideline (CPG) established in the Cardiovascular Program at the Children's Hospital, Boston, MA. This retrospective review was undertaken to determine whether this practice was efficient without compromising patient care. The charts and hospital charges for 102 patients undergoing secundum ASD or sinus venosus defect surgery between March 1992 and July 1994 were reviewed; 36 patients (Group I) had surgery prior to introduction of the CPG, and 66 patients were managed according to the CPG. Of the latter, 25 patients (Group II) were tracheally extubated in the operating room (OR) and 41 patients (Group III) were extubated in the cardiac intensive care unit (CICU). Patients in all three groups were similar with respect to height, weight, and surgical conditions including cardiopulmonary bypass time, lowest esophageal temperature, hematocrit, total OR time, and the time from completion of bypass to leaving the OR. Patients in Group II received significantly less fentanyl during anesthesia, were more likely to have a respiratory acidosis on admission to the CICU, and had an increased frequency of vomiting in the CICU. There was no difference in duration of CICU stay among groups. The length of hospital stay was reduced in Groups II and III after introduction of the CPGs, but was not influenced by tracheal extubation in the OR. There was no difference among groups in the hospital charges for OR, anesthesia and CICU time. However, when the combined hospital charges for services provided both in the OR and CICU were included, patients in Group II were charged significantly less, and this primarily reflects the absence of postoperative mechanical ventilation charges. Tracheal extubation in the OR after ASD surgery in children can result in lower patient charges without significantly compromising patient care.

General internal medicine practice trends in large multispecialty clinics.

OBJECTIVE: To assess practice trends in the general internal medicine departments of large multispecialty clinics. DESIGN: A survey questionnaire addressing the following issues: 1) department size and rate of growth, 2) services provided, 3) patient population, 4) individual clinical workload, 5) call arrangements, 6) time away from practice, and 7) benefits and salary. PARTICIPANTS: 22 multispecialty clinics, with a mean of 279 physicians. MEASUREMENTS AND RESULTS: Mean general internal medicine department physician expansion was 28% over the preceding three years. Primary care, clinic system access, care of patients laterally shifted from subspecialty internists, and preoperative evaluations were the four major services provided. The mix of fee-for-service, Medicare/Medicaid, and prepaid-plan patients was diverse. Mean outpatient clinical scheduling was 35 hours per week exclusive of hospital practice, administrative time, and paperwork. Study of call arrangements revealed a definite trend toward a group practice model of shared responsibility during the day as well as nights and weekends. Mean meeting and vacation time was 35 days per year. Salary was set by committee, formula, or both. Department stresses and dissatisfactions were also reported. CONCLUSIONS: Rapid expansion of general internal medicine departments and services will continue as subspecialists back away from providing primary care. The evolution of general internal medicine practice must be anticipated and managed for optimal patient and departmental outcomes.

Short-term medical service in the developing world.

Medicine as it is practiced in the developing world is far removed from medicine as we know it in the United States. It is the authors' opinion that the developing world offers a stimulating environment medically, culturally, and ethically. Those physicians who devote some portion of their careers to practicing in the developing world reap significant rewards. The authors describe how they found and selected medical situations in the developing world and the experiences they had delivering health care in those situations.

Plasma and cerebrospinal fluid nucleosides and oxypurines in acute liver failure.

Concentrations of pyrimidine nucleosides (with the possible exception of uridine) and oxypurines in mammalian plasma and cerebrospinal fluid (CSF) are maintained relatively constant by potent homeostatic mechanisms. To test the importance of the intact liver in maintaining homeostasis of pyrimidine nucleosides and oxypurines in plasma and CSF, we performed a greater than 90% or sham hepatectomy on New Zealand white rabbits. At 1, 6, 12, or 24 hours after real or sham hepatectomy, plasma and CSF nucleosides and oxypurines were measured by high-performance liquid chromatography. At all times after hepatectomy, the concentrations of the pyrimidine deoxyribonucleosides (deoxycytidine, deoxyuridine, and thymidine) were increased approximately threefold in plasma and CSF compared with sham-operated controls. Twenty-four hours after hepatectomy, the concentrations of uridine and cytidine in plasma were decreased by 70% and 50%, respectively, and in CSF by 50% and 40%, respectively, when compared with the concentrations in the sham-operated controls. Hypoxanthine concentrations in CSF were increased approximately twofold at 6, 12, and 24 hours after hepatectomy. These results suggest that liver function is essential for the maintenance of normal concentrations of pyrimidine nucleosides in plasma and CSF. That pyrimidine nucleoside concentrations are disrupted in plasma and CSF in this model of acute liver failure suggests that pools of pyrimidine nucleotides in some tissues (e.g., brain) may be altered by liver failure.

Effect of a 400-kilocalorie carbohydrate diet on human plasma uridine and hypoxanthine concentrations.

Seven healthy female volunteers were fed a 400-kcal carbohydrate diet for 4 days after eating a standardized diet for 3 days. Plasma uridine and hypoxanthine concentrations were measured by high-performance liquid chromatography. After 4 days on the 400-kcal diet, the plasma uridine concentration decreased by 35% but the plasma hypoxanthine concentration remained stable.