New device for nonvolitional evaluation of quadriceps force in ventilated patients.
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ABSTRACT:
SUBMITTER: Laghi F
PROVIDER: S-EPMC5910250 | biostudies-literature | 2018 May
REPOSITORIES: biostudies-literature
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New device for nonvolitional evaluation of quadriceps force in ventilated patients.
Laghi Franco F Khan Najeeb N Schnell Thimothy T Aleksonis Dinas D Hammond Kendra K Shaikh Hameeda H Collins Eileen E Jubran Amal A Tobin Martin J MJ
Muscle & nerve 20171211 5
<h4>Introduction</h4>In mechanically ventilated patients, nonvolitional assessment of quadriceps weakness using femoral-nerve stimulation (twitch force) while the leg rests on a right-angle trapezoid or dangles from the bed edge is impractical. Accordingly, we developed a knee-support apparatus for use in ventilated patients.<h4>Methods</h4>Ninety subjects (12 ventilated patients, 28 ambulatory patients, and 50 healthy subjects) were enrolled. Twitches with leg-dangling, trapezoid, and knee-supp ...[more]
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Project description:BackgroundIntensive care unit acquired weakness is a serious problem, contributing to respiratory failure and reductions in ambulation. Currently, there is no pharmacological therapy for this condition. Studies indicate, however, that both beta-hydroxy-beta-methylbutyrate (HMB) and eicosapentaenoic acid (EPA) increase muscle function in patients with cancer and in older adults. The purpose of this study was to determine whether HMB and/or EPA administration would increase diaphragm and quadriceps strength in mechanically ventilated patients.MethodsStudies were performed on 83 mechanically ventilated patients who were recruited from the Medical Intensive Care Units at the University of Kentucky. Diaphragm strength was assessed as the trans-diaphragmatic pressure generated by supramaximal magnetic phrenic nerve stimulation (PdiTw). Quadriceps strength was assessed as leg force generated by supramaximal magnetic femoral nerve stimulation (QuadTw). Diaphragm and quadriceps thickness were assessed by ultrasound. Baseline measurements of muscle strength and size were performed, and patients were then randomized to one of four treatment groups (placebo, HMB 3 gm/day, EPA 2 gm/day and HMB plus EPA). Strength and size measurements were repeated 11 days after study entry. ANCOVA statistical testing was used to compare variables across the four experimental groups.ResultsTreatments failed to increase the strength and thickness of either the diaphragm or quadriceps when compared to placebo. In addition, treatments also failed to decrease the duration of mechanical ventilation after study entry.ConclusionsThese results indicate that a 10-day course of HMB and/or EPA does not improve skeletal muscle strength in critically ill mechanically ventilated patients. These findings also confirm previous reports that diaphragm and leg strength in these patients are profoundly low. Additional studies will be needed to examine the effects of other anabolic agents and innovative forms of physical therapy.Trial registrationClinicalTrials.gov, NCT01270516. Registered 5 January 2011, https://clinicaltrials.gov/ct2/show/NCT01270516?term=Supinski&draw=2&rank=4 .
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