The Malfunctioning Pacemaker System. Part I

The success of an implanted cardiac pacemaker is dependent upon the establishment of a harmonious relationship between the artificial pacemaker and the human receiver. Failure of a pacemaker system may arise from an electronic or mechanical defect within the pacemaker, a physiologic problem, or from a poor relationship between the normal function of both. Such malfunctions may necessitate the repair, replacement, or repositioning of a pacemaker component or removal of a source of external interference. True pacemaker malfunctions must be clearly distinguished from pseudo-malfunctions, where there is no pacemaker system defect. These situations may, variously, require the repair of faulty testing equipment, reassessment of falsely interpreted test data, or treatment of the patient for an unrelated disorder. This paper outlines a system for investigating patients with suspected pacemaker malfunction. For simplicity, only malfunctions associated with the ventricular inhibited pacing system will be discussed.     

Immunization: a 1991 update. Part I.

Immunization is an important and changing area in pediatric practice. The school nurse plays a pivotal role in the ascertainment of appropriate immunization status for school children. The American Academy of Pediatrics Committee on Infectious Disease has made a number of recent substantive changes in immunization requirements for both preschool and school-age children. This article will review the salient features of those changes, especially those related to school nursing practice.     

Injections of joints and soft tissue: Part I. General guidelines

Joint and soft tissue injections may be used therapeutically and as diagnostic tests to differentiate various pain syndromes. With proper patient selection and the use of appropriate injection techniques, morbidity can be less than that seen with nonsteroidal anti-inflammatory drug therapy. Family physicians can readily learn aspiration and injection techniques and should be able to perform injections of most anatomic sites.     

Evidence-based prenatal care: Part I. General prenatal care and counseling issues

Effective prenatal care should integrate the best available evidence into a model of shared decision making. Pregnant women should be counseled about the risks of smoking and alcohol and drug use. Structured educational programs to promote breastfeeding are effective. Routine fetal heart auscultation, urinalysis, and assessment of maternal weight, blood pressure, and fundal height generally are recommended, although the evidence for these interventions is variable. Women should be offered ABO and Rh blood typing and screening for anemia during the first prenatal visit. Genetic counseling and testing should be offered to couples with a family history of genetic disorders, a previously affected fetus or child, or a history of recurrent miscarriage. All women should be offered prenatal serum marker screening for neural tube defects and aneuploidy. Women at increased risk for aneuploidy should be offered amniocentesis or chorionic villus sampling. Counseling about the limitations and risks of these tests, as well as their psychologic implications, is necessary. Folic acid supplementation beginning in the preconception period reduces the incidence of neural tube defects. There is limited evidence that routine use of other dietary supplements may improve outcomes for the mother and infant.     

Chlamydial infection. Screening and management update, 1992.

The need for a cost-effective, highly sensitive and specific test for Chlamydia trachomatis infection remains, although progress is being made. Clinicians can minimize the incidence of complications and erroneous test results by being alert to the possibility of this infection, screening appropriate patients, using careful collection techniques, following the most recent treatment recommendations, and knowing the limitations of available tests.     

Ophthalmology update for primary practitioners. Part I. Update on optic neuritis

Optic neuritis is a common cause of acute visual loss. It is typified by sudden onset of visual impairment and pain with eye movements, followed by spontaneous recovery of vision over several months. Pathologically, optic neuritis is an acute demyelinating event affecting the optic nerve. Objective physical findings are typically few, including an afferent pupillary defect or Marcus-Gunn pupil, whereas subjective psychophysical findings abound (ie, diminished central visual acuity, color vision, decreased contrast sensitivity, and visual field abnormalities). These characteristics have made the diagnosis of optic neuritis based solely on clinical grounds disquieting to practitioner and patient alike. In addition, the fact that optic neuritis is often associated with multiple sclerosis as the first clinical manifestation of disease gives further reason for both patient and physician anxiety. The serious nature of visual loss and the consequences of making the diagnosis of optic neuritis has given rise to extensive testing and expensive treatments. This review is intended to explore our current state of knowledge with regard to (1) clinical presentation, (2) ancillary testing, (3) therapeutic intervention, and (4) associated disease, specifically the risk for multiple sclerosis in the patient who presents with an acute optic neuritis. Finally, a suggestion guide for informing the patient and addressing his or her concerns will be presented.     

Virtual scanning--a new system of medical assessment and treatment: Part I. Assessment

PURPOSE: We summarize fundamental concepts and research supporting Virtual Scanning, a Russian system of health assessment and treatment, which uses computer modeling of brain function to analyze color cognition and so identify and evaluate specific influences from all parts of the nervous system. METHODS: In Virtual Scanning, quantitative estimates of deviation from predefined measures of good health of all body parts, including organs and organ systems, yield a body scan in virtual reality. RESULTS: Russian evaluations are summarized, with examples of instances in which Virtual Scanning was found to provide early warnings of clinical conditions before conventional tests had detected problems.     

Immunization: a 1991 update. Part II.

Immunization is an important and changing area in pediatric practice. The school nurse plays a pivotal role in the ascertainment of appropriate immunization status for school children. The American Academy of Pediatrics Committee on Infectious Disease has made a number of recent substantive changes in immunization requirements for both preschool and school-age children. This article will review the salient features of those changes, especially those related to school nursing practice.     

Asthma: an anesthetic update. Part 3.

The effective management of the patient with asthma continues to represent a significant challenge in modern anesthesia practice. The prevalence of asthma is increasing worldwide and is the most common chronic disorder among children. Classification and treatment strategies continue to evolve as new therapies emerge. Fortunately, the incidence of bronchospastic episodes under anesthesia has declined in recent years with the development of improved anesthetic drugs and techniques. A thorough understanding of the pathogenesis of asthma will assist in developing anesthetic management plans that are patient specific and use the best treatment pathways currently available.     

Asthma update: Part II. Medical management

The National Asthma Education and Prevention Program recently updated its guidelines for the management of asthma. An evidence-based approach was used to examine several key issues regarding appropriate medical therapy for patients with asthma. The updated guidelines have clarified these issues and should alter the way physicians prescribe asthma medications. Chronic inhaled corticosteroid use is safe in adults and children, and inhaled corticosteroids are recommended as first-line therapy in adults and children with persistent asthma, even if the disease is mild. Other medications, such as cromolyn, theophylline, and leukotriene modifiers, now are considered alternative treatments and should have a more limited role in the management of persistent asthma. The addition of a long-acting beta2 agonist to an inhaled corticosteroid is superior to all other combinations as well as to higher dosages of inhaled corticosteroids alone. Combination therapy with an inhaled corticosteroid and a long-acting beta2 agonist is the preferred treatment for adults and children with moderate to severe asthma. Antibiotic therapy offers no additional benefit in patients with asthma exacerbations.