ABSTRACT
The proliferation of Integrated Delivery Systems (IDSs) in regional health care markets has resulted in the movement of these markets from a monopolistic competitive model of behavior to an oligopoly. An oligopoly is synonymous with competition among the few, as a small number of firms supply a dominant share of an industry's total output. The basic characteristics of a market with competition among the few are: (1) A mutual interdependence among the actions and behaviors of competing firms; (2) competition tends to rely on the differentiation of products; (3) significant barriers to entering the market exist; (4) the demand curve for services may be kinked; and (5) firms can benefit from economies of scale. An understanding of these characteristics is essential to the survival of IDSs as regional managed care markets mature.
Subject(s)
Delivery of Health Care, Integrated/organization & administration , Health Care Sector/trends , Costs and Cost Analysis/trends , Delivery of Health Care, Integrated/economics , Economic Competition , Health Facility Merger/economics , Health Facility Merger/organization & administration , Marketing of Health Services , Models, Economic , United StatesABSTRACT
Operations Desert Shield/Storm involved the recall of 9,700 Navy medical reservists. A demographically representative sample of 3,804 medical reservists (39%) responded to a survey between June and September 1991. The purpose was to identify major issues associated with the recall experience. Results indicated that reservists felt well prepared for their recall assignments; however, they did not strongly endorse the Reserve training program. Responses across operationally oriented issues were moderately positive. Reservists assigned to CONUS hospitals rated items more positively than those assigned to Marine Corps support, and officers were more positive than hospital corpsmen. Results are presented as a descriptive heuristic for policy considerations.
Subject(s)
Military Personnel/psychology , Naval Medicine , Warfare , Adolescent , Adult , Aged , Attitude , Female , Humans , Male , Middle Aged , Middle East , United StatesABSTRACT
The term Total Force has been historically used to describe the relationship between reserve and active components of the armed services. As a result of the Desert Storm experience, concerns about the Total Force concept in practice were identified by both reserve and active medical personnel. Utilizing the results of recent studies and input from reserve Navy Nurse Corps officers serving on active duty in key positions, this essay provides a clear definition of the Total Force concept and provides a model for implementation throughout the Navy Medical Department.
Subject(s)
Military Nursing/organization & administration , Military Personnel , Awards and Prizes , Decision Making , Humans , Models, Organizational , Organizational Policy , Societies, Medical , United StatesABSTRACT
Atrial natriuretic peptide (ANP) is a hormone involved in fluid and blood pressure homeostasis. We studied the effects of left-to-right shunting through a patent ductus arteriosus on blood pressure changes and plasma ANP concentrations in newborn piglets. In five experimental piglets, the ductus arteriosus was bathed with PGE1 and infiltrated with formalin to maintain its patency. In four age-matched control piglets, the ductus arteriosus was ligated. Plasma ANP concentrations and blood pressure determinations were obtained prior to (base-line) and 25 +/- 1 h (day 1), and 48 +/- 1 h (day 2) after surgery. Radionuclide-microsphere determinations of left-to-right patent ductus arteriosus shunts were performed on days 1 and 2 in the 5 piglets with a patent ductus arteriosus. Plasma ANP concentrations were significantly elevated in the left atrium on day 1 and the right atrium on day 2 in the PDA piglets. No correlation was demonstrated between plasma ANP concentrations and right or left atrial pressures. We conclude that left and right plasma atrial ANP concentrations are significantly elevated in newborn piglets with left-to-right patent ductus arteriosus shunts.
Subject(s)
Animals, Newborn/blood , Atrial Natriuretic Factor/blood , Ductus Arteriosus, Patent/blood , Animals , Body Weight/physiology , Ductus Arteriosus, Patent/physiopathology , Hemodynamics/physiology , SwineSubject(s)
Cation Exchange Resins/therapeutic use , Glucose/therapeutic use , Hyperkalemia/drug therapy , Infant, Premature, Diseases/drug therapy , Insulin/therapeutic use , Polystyrenes/therapeutic use , Administration, Rectal , Cation Exchange Resins/administration & dosage , Glucose/administration & dosage , Humans , Infant, Low Birth Weight , Infant, Newborn , Infusions, Intravenous , Insulin/administration & dosage , Polystyrenes/administration & dosageABSTRACT
Patent ductus arteriosus (PDA) is a common form of congenital heart disease in full-term infants. To investigate the morbidities associated with a left to right PDA shunt, we produced a PDA in six full-term newborn piglets (less than 36 hours old) by bathing the ductus arteriosus with prostaglandin E (PGE) and infiltrating it with formalin. In five age-matched piglets, the ductus arteriosus was ligated to serve as controls. Microsphere determinations of left ventricular output (LVO) and regional blood flow (Q) were made on three consecutive days. We produced left to right shunts of 36 to 47% (mean) in the experimental piglets. The experimental piglets had a 22 to 36% increase in LVO with a one- to twofold reduction in percentage of LVO to the kidneys and carcass (p less than 0.05). Although percentage of LVO to the gastrointestinal tract was reduced (p less than 0.05), no reduction of absolute Q to the gastrointestinal tract was observed. Brain and heart Q were similar in both groups. We conclude that significant hemodynamic changes result from left to right shunting in the full-term newborn piglet with PDA. These hemodynamic changes, such as reduction in renal blood flow, are relevant information that will help explain the morbidities observed in infants with a hemodynamically significant PDA with a left to right shunt.
Subject(s)
Ductus Arteriosus, Patent/physiopathology , Hemodynamics , Animals , Blood Circulation , Blood Gas Analysis , Blood Pressure , Cardiac Output , Disease Models, Animal , Ductus Arteriosus, Patent/blood , Ductus Arteriosus, Patent/epidemiology , Heart Rate , Morbidity , Prostaglandins E/pharmacology , SwineABSTRACT
Controversy exists regarding the placental permeability of erythropoietin (Ep), a glycoprotein hormone that regulates red blood cell production in the fetus, newborn, and adult after tissue hypoxia. The purpose of the current study was to determine the placental permeability of biologically active 35S-labeled human recombinant erythropoietin given by bolus injection into the circulation of the fetal lamb. Specific radioactivity in fetal plasma trichloroacetic acid protein precipitate fractions increased 13-fold from preinfusion levels at 6 h (47 +/- 1.3 to 679 +/- 237 cpm/mL) and thereafter fell progressively until the study was terminated at 45 h. In contrast, maternal trichloroacetic acid protein precipitate fractions demonstrated no detectable increase in radioactivity at any time. Based on the counting precision, a rise in maternal plasma radioactivity of more than 3 cpm/mL would have been detected (i.e. 0.5% of the 582 cpm/mL rise in the fetal protein precipitate counts at six h). Similar data were obtained with simultaneously administered unlabeled human urinary Ep. We conclude that physiologically significant amounts of Ep do not cross from fetus to mother; hence, maternal Ep level functions as a separate indicator of the adequacy of tissue oxygenation in the maternal compartment.
