June 2008, Volume 38 Number 6 , p 27 - 27 [FREE]



function set_JnlFullText_Print() { metaTag = document.createElement('meta'); metaTag.setAttribute('name','OvidPageId'); metaTag.setAttribute('content','JnlFullText_Print'); head = document.getElementsByTagName('head')[0]; head.appendChild(metaTag); return; } if (window.addEventListener) { // DOM Level 2 Event Module (NS 6+) // Firefox throws an uncaught exception error executing this // code, even though it seems to work. Adding a do nothing // try/catch clause around it for now, since the exection itself // appears to be innocuous try { window.addEventListener('onload',set_JnlFullText_Print(),false); } catch(e) {} } else if (window.attachEvent) { // IE 5+ Event Model window.attachEvent('onload',set_JnlFullText_Print); } // For anything else, just don't add the event Display Knowledge Base Logoff Full Text #header-block { display: none; } $().ready( function() { window.print(); } ); Why weaning may be a problem DOI: 10.1097/01.NURSE.0000320351.71455.3f ISSN: 0360-4039 Accession: 00152193-200806000-00026 ...


Mechanical ventilation can weaken lung muscles in as little as 18 hours of use, according to a new study that helps explain why weaning some patients from a ventilator is so difficult. The results suggest that the practice of providing ventilator support to "rest" a patient's respiratory muscles may encourage atrophy of the diaphragm and be counterproductive.


Researchers analyzed diaphragm biopsy specimens from 14 patients who were brain-dead and who'd been on a ventilator for 18 to 69 hours, and from 8 surgical patients who'd been on a ventilator for no more than 3 hours. They found that patients who'd been on a ventilator for longer periods had atrophy of diaphragm myofibers.


Researchers say their findings are consistent with increased breakdown of diaphragmatic proteins (proteolysis) during inactivity. They speculate that blocking or attenuating diaphragm proteolytic pathways in patients on ventilators might reduce problems with weaning.



Levine S, et al., Rapid disuse atrophy of diaphragm fibers in mechanically ventilated humans, The New England Journal of Medicine, March 27, 2008; Sieck GC, Mantilla CB, Effect of mechanical ventilation on the diaphragm, The New England Journal of Medicine, March 27, 2008.