MEASUREMENTS OF INTERFACE PRESSURE BETWEEN BODY SITES AND THE SURFACES OF FOUR SPECIALISED AIR MATTRESSES

SUMMARY Four specialised air mattresses had interface pressure measured under six body sites prone to pressure sores in 10 subjects, supine and sitting. The mattresses were the Clinirest (SSI) and FirstStep (KCI) continuous airflow mattress overlays, and Airwave (Pegasus) and Nimbus (Huntleigh) alternating pressure air mattresses. On the mattress overlays, average supine interface pressures were 2.33 kPa (scapula), 4.15 kPa (elbow), 1.94 kPa (sacrum) and 2.79 kPa (buttock), although they were higher at the occiput (7.97 kPa) and heel (11.7 kPa). The alternating pressure air mattresses had an average minimum interface pressure close to zero for three sites, rising to 4.28 kPa under the heel. Average maximum interface pressures were 8.61 kPa (occiput), 5.21 kPa (scapula), 4.90 (elbow), 4.85 kPa (sacrum), 4.61 kPa (buttock) and 13.2 kPa (heel). No accepted scientific method exists for comparing the two types of mattress. Our data suggest a clinical benefit at the occiput and heel (supine) in using an alternating pressure air mattress and a benefit in using a continuous airflow mattress overlay at other sites.     

Pathophysiological aspects of predominant preload lowering on pulmonary circulation, gas exchange, and the biventricular function in patients with chronic obstructive lung disease

A group of 21 patients with various degrees of chronic obstructive pulmonary disease underwent radionuclide ventriculography with hemodynamic monitoring to assess the extent to which pulmonary artery pressures and pulmonary vascular resistance can be lowered by the vasodilator molsidomine. Molsidomine (N-carboxy-3-morpholino-sydnonimin-ethylester) is similar to nitroglycerin in its mode of action. After hemodynamic and radionuclide data acquisition, at rest and during submaximal exercise in the steady state, 2 mg molsidomine was injected intravenously. Rest and exercise measurements were repeated 45 min after molsidomine injection. In patients with mild to moderate disease (group 1), pulmonary artery resting pressures decreased by 12% (p less than 0.05) at rest by 22% (p less than 0.01) during exercise after the administration of the drug. Total pulmonary resistance during exercise decreased significantly (p less than 0.01) as a result of marked decrease of pulmonary artery pressure (PAP) compared with a minimal decrease in cardiac index (CI). In patients with severe disease (group 2), only the resting values of PAP decreased while the relationship between pressure and flow was unchanged. During the exercise period, the preload parameters of the right and left ventricles decreased by an average of 30%. With regard to gas exchange, only the arterial PO2 at rest decreased slightly but significantly (p less than 0.05) after molsidomine, while the coefficient of oxygen delivery was not affected by the drug. However, in four patients arterial PO2 was markedly reduced by the drug. Right ventricular ejection fraction increased significantly (p less than 0.01) both at rest and during exercise in group 1 and during exercise in group 2 after administration of molsidomine.(ABSTRACT TRUNCATED AT 250 WORDS)     

Radiology and the Health Policy Agenda for the American People

Eleven radiologists appointed by the major radiological societies participated for the past 5 years in the development of the Health Policy Agenda for the American People. The Agenda is an action plan to address a wide variety of serious problems in medicine. The first phase involved establishment of 159 principles, broad value statements that were the foundation of the project. Phase 2 involved the development of policy proposals on 38 urgent issues for action in medical science; education; health resources; delivery mechanisms; evaluation, assessment, and control; and payment for services. These proposals are summarized in this report. The activities and recommendations of representatives for the field of radiology are described. The Agenda has been released, and an implementation phase has begun. It will likely be of great importance to the practice of radiology over the next decade. Important issues can be addressed by acting with the coalitions that are being formed from among the more than 150 participating organizations.     

Genetic linkage of the tricho-dento-osseous syndrome to chromosome 17q21

Tricho-dento-osseous syndrome (TDO), MIM# 190320, is transmitted as a highly penetrant autosomal dominant trait that is characterized by variable clinical expression. The principal clinical features include kinky/curly hair in infancy, enamel hypoplasia, taurodontism, as well as increased thickness and density of cranial bones. Possible genetic linkage has been reported for TDO with the ABO blood group locus, but the gene defect remains unknown. We have identified four multiplex families (n = 63, 39 affected, 24 unaffected) from North Carolina segregating TDO. We previously have excluded a major locus for TDO in the ABO region for these families. Utilizing a genome-wide search strategy, we obtained conclusive evidence for linkage of the TDO syndrome locus to markers on chromosome 17q21 (D17S791, Z max = 10.54, Theta = 0.00) with no indication of genetic heterogeneity. Multipoint analysis suggests the TDO locus is located in a 7 cM chromosomal segment flanked by D17S932 and D17S941. This finding represents the first step towards isolation and cloning of the TDO gene. Identification of this gene has important implications for understanding normal and abnormal craniofacial development of hair, teeth and bone.