Development of clinical indicators for performance measurement and improvement: an HMO/purchaser collaborative effort

This article describes a collaborative effort between a major health care purchaser, three area health maintenance organizations, and a state Medicaid agency to develop clinical indicators as the basis for a comparison database. Some of the difficulties in developing a "common yardstick" of quality and value are candidly discussed.     

Border crossing for hospital care and its implications for the use of statewide data

A major concern of researchers using state data sets for population-based analyses and market share studies in the health care sector is the potential bias caused by 'border crossing'--patients receiving care out of state. By using the Health Care Financing Administration (HCFA) discharge abstract files for 1987 and 1988, we found that 'border crossing' is not a serious problem for the two large states we examined. Only 4.4% of New York patients and 2.15% of California patients received care out of state. At the county and zip code level, 'border crossing' is more frequent but tends to be concentrated in areas adjacent to other states. Even excluding all zips with more than 10% of patients crossing the 'border' results in a small loss of patients (2.2% for New York and 1.0% for California).     

Heart muscle cells acutely infected with Trypanosoma cruzi: characterization of electrophysiology and neurotransmitter responses

Primary cell cultures of mouse ventricular myocardium were infected with Trypanosoma cruzi, to study the consequences of T. cruzi-muscle cell interaction on the rate of spontaneous contractions, on the responses to norepinephrine, and on action potential parameters. Single cells or small cell groups of infected cultures were subjected to pharmacological and electrophysiological experiments. In concentrations ranging from 1 nM to 100 microM, norepinephrine exerted positive or negative chronotropic effects mediated by alpha-adrenergic receptors. A significant number of infected cells (25%) did not respond to the agonist. Two days after infection the cultures exhibited a higher frequency of spontaneous contractions (20%), paralleled by an increase in firing rate and a decrease in the action potential duration without significant changes in maximum diastolic potential and action potential amplitude. A decrease in alpha-adrenergic receptor-mediated positive chronotropic response to norepinephrine was also observed in 2-day infected cells. Cells made to phagocyte ferritin particles showed an increase in the rate of spontaneous contractions, but no changes in the positive chronotropic responses to norepinephrine. In conclusion, these observations show that during acute infection with T. cruzi, there are alterations in automaticity and in the chronotropic responses to norepinephrine, whose mechanisms are related to the process of parasite endocytosis by the cardiac cells.     

Collection and transfusion of blood and blood components in the United States, 1989

A poor response to L-DOPA in addition to parkinsonian, cerebellar, and autonomic signs is commonly regarded as indicative of clinical multiple system atrophy (MSA). We compared the motor response to a single oral administration of 250 mg L-DOPA/25 mg carbidopa in eight MSA patients and eight Parkinson's disease (PD) patients with the "on-off" phenomenon, evaluating L-DOPA peripheral pharmacokinetics. Motor response was consistently good in all PD patients, but only four MSA patients had a (moderate) response. Pharmacokinetic parameters did not differ between the groups. The varying extent of putaminal damage could be responsible for the differing motor response to L-DOPA in MSA patients.     

Structures of sialylated oligosaccharides of human erythropoietin expressed in recombinant BHK-21 cells

The native structures of the Asn-linked oligosaccharides and the O-glycans at Ser126 of human erythropoietin expressed from recombinant BHK cells have been elucidated. Enzymatically released N-glycans were studied by methylation analyses, fast-atom-bombardment mass spectrometry as well as one- and two-dimensional 1H-NMR spectrometry at 600 MHz. Many (82.7%) were found to be tetraantennary N-acetyllactosamine-type (22.8% with one, 3.6% with two and 0.4% with three N-acetyllactosamine repeats) being tetrasialylated (41%), trisialylated (29.6%) and disialylated (12.2%). A few (9.7%; 4.1% 2,4-branched, 5.6%, 2,6-branched) of the chains were triantennary (5.4% trisialyl, 4.3% disialyl) and 4.6% were of the disialyl diantennary type. Almost all of the innermost GlcNAc residues were alpha 1-6 fucosylated and NeuAc was exclusively alpha 2-3 linked to Gal beta 1-4GlcNAc-R; 60% of the protein was found to be O-glycosylated at Ser126; structures were monosialylated (70%) or disialylated (30%) forms of the Gal beta 1-3GalNAc core type. Glycosylation patterns at individual Asn-Xaa-Thr/Ser sites were determined by analytical high-pH anion-exchange chromatography with pulsed amperometric detection. Only tetraantennary chains with 0-3 N-acetyllactosamine repeats were detected at Asn38 and Asn83, while almost all of the di- and triantennary oligosaccharides were attached to Asn24. Batch analysis of different preparations of recombinant erythropoietin revealed the high reproducibility of the production procedure. Structures containing terminal GalNAc-GlcNAc were detected in small amounts in a few batches.     

Head trauma

Progress in research includes studies concerning the pathophysiology and outcome of pediatric head injury, the pathology of the hippocampus in fatal injury, and the use of multivariate statistics to predict outcome in survivors. Recent research has confirmed and extended findings regarding the differential effects of closed head injury, depending on the age of the individual. These studies indicate that the consequences of head injury are more severe in older adults and in children younger than 2 years. Neuroimaging findings include evidence for delayed brain injury as a major cause of mortality and disability. Functional brain imaging provides evidence for cerebral dysfunction that is not appreciated by structural brain imaging techniques and may have a stronger relationship to neurobehavioral sequelae. The neurobehavioral sequelae frequently implicate frontal dysfunction, even in the absence of structural findings on computed tomography or magnetic resonance imaging. Studies of mild head injury have expanded our knowledge concerning the pathogenesis of postconcussional symptoms, including a preinjury vulnerability based on recent life events. Persistent postconcussional symptoms after mild head injury are frequently associated with emotional disturbance of clinical proportions.     

Are endoscopic measurements of colonic polyps reliable?

Many clinical studies of colorectal adenomatous polyps rely on endoscopic estimation of polyp size. To examine the reliability of such measurements, we conducted a study using artificial polyps in an endoscopy teaching model. Eight experienced endoscopists estimated the size of 13 polyps in two separate sessions 2 wk apart. Endoscopic estimates of polyp size tended to be significantly lower than the true polyp size for all polyps and all endoscopists at both sessions. We also found a statistically significant difference in the magnitude of the underestimation between the first and second session (p < 0.0001). At the first session, polyps tended to be estimated at 64% of their true size, and at the second session, the estimates tended to be at 77% of the actual polyp size. We estimate the magnitude of the variation in polyp measurements due to individual polyps, endoscopist, and examination session, and discuss the impact these sources of variation have in planning of clinical trials.     

The effect of erythromycin on motility of the duodenum, sphincter of Oddi, and gallbladder in the prairie dog

Over the past 9 years, the fertility potential for men with spinal cord injury and other neurological impairments has improved. Approximately 80% of men with spinal cord injury have semen (collected either by vibration or by electroejaculation using rectal probe) of sufficient quality to use in intrauterine insemination or in vitro fertilization. Assuming that other factors are equal, it would seem that length or level of injury are not dominating factors that control the quality of semen from these men.     

Predictors of outcome following severe head trauma: follow-up data from the Traumatic Coma Data Bank

Outcome as a function of employment status or return to school was evaluated in severely head-injured patients. A priori we selected the most salient demographic, physiological, neuropsychological and psychosocial outcome predictors with the aim of identifying which of there variables captured at baseline or 6 months would best predict employability at 6 or 12 months. Based on the patients evaluated at 6 months, 18% of former workers had returned to gainful employment and 62% of former students had returned to school. For those not back to work or school at 6 months, 31% of the former workers and 66% of the former students had returned by 12 months. Age, length of coma, speed for both attending and motor movements, spatial integration, and intact vocabulary were all significantly related to returning to work or school. The three most potent predictors for returning to work or school were intactness of the patient's verbal intellectual power, speed of information processing and age.     

Tumor labeling indices of primary breast cancers and their regional lymph node metastases

BACKGROUND: Tumor labeling index has emerged as a strong predictor of the clinical course of women with breast cancer. This study investigated whether labeling index of primary tumors correlates with labeling indices of concurrent regional node metastases. METHODS: With appropriate written consent, preoperative in vivo infusion of the thymidine analogue 5-bromodeoxyuridine (BrdUrd) was used to label 109 human breast cancers. Labeled S-phase cells were identified immunohistochemically with an antibody specific to DNA-incorporated BrdUrd. Labeling index was the fraction of labeled nuclei in 2000 tumor nuclei. For 30 women, there was sufficient cancer in axillary lymph nodes to compare labeling indices in primary breast cancer and regional lymph node metastases. RESULTS: The 30 women were from 25 to 82 years of age. Tumors were from 1 to 12 cm in size and there were from 1 to 26 positive nodes. Tumor labeling index ranged from 0.1% to 34%, (mean, 11.1%; median, 10.3%) and axillary lymph node metastasis labeling index ranged from 0.1% to 27.7% (mean, 10.8%; median, 10.0%). There was strong correlation between primary tumor labeling index and regional lymph node metastases labeling index (r = 0.82, with 95% confidence interval 0.65-0.91). The correlation persisted within subgroups according to age, tumor size, number of positive nodes, and hormone receptor status. Primary tumor and lymph node metastases labeling indices also had statistically similar relationships with age, level of hormone receptors, tumor size, and number of positive nodes. CONCLUSIONS: Primary tumor and regional node labeling indices correlate strongly; the relationship is not influenced by age, level of hormone receptors, tumor size, or number of positive nodes.