Comparison of ultrasound with computed tomography to measure skeletal muscle mass in critically ill patients: A prospective study protocol

Abstract

Introduction: Therapy and nutritional status directly interfere in the clinical evolution of critically ill patients, in reducing morbidity and mortality, by maintaining the functional integrity of the gastrointestinal tract, decreasing the catabolic response, besides contributing to the reduction of hospitalization time resulting in less treatment cost. Critical patients and trauma victims suffer early changes in the quantity and quality of muscle mass. Tools to identify the groups most susceptible to these complications are necessary so that interventions can minimize the deleterious effects of malnutrition in critically ill patients. Methods and analysis: The aim of the present study is to measure muscle mass loss by measuring the thickness of the rectus femoris muscle by bedside ultrasound in critically ill patients admitted to the Intensive Care Unit (ICU) of a university hospital. Information will be collected regarding the length of hospital and ICU stay, the reason for admission, anthropometric data at admission and during hospitalization, energy needs, nutritional therapy used, and fasting time. This is a prospective, observational study that will be carried out in a single center in an ICU of a tertiary university hospital. The study population will undergo 3 tomographic images and 3 ultrasounds of the rectus femoris of each patient at different times. We propose, unprecedentedly, performing a validation study of ultrasound with the gold standard Computed tomography to evaluate the musculature of critically ill patients victims of traumatic brain injury. The results got will texto be fundamental for the development of new fields of investigation and certainly contribute to the discovery of a new approach to treat sarcopenia in critically ill patients. The Research Ethics Committee approved the study and all patients included will sign an informed consent form. (Clinical Record: RBR-2bzspnz).

Biceps brachii muscle cross‐sectional area measured by ultrasonography is independently associated with one‐month mortality: A prospective observational study

“…With aging, there is a predominant loss of type 2 (fast‐twitch) muscle fibers, whereas type 1 fibers do not alter significantly 60 . Lower limb muscles are predisposed to rapid atrophy compared to the upper limbs due to the distribution of muscle fibers 61 . The rectus femoris is rich in type 2 fibers 62 while the biceps brachii usually does not show fiber‐type dominance but may be more sensitive to neurogenic modifications induced by activities of daily living and cervical spondylosis than lower extremity muscles 63 .…”

“…60 Lower limb muscles are predisposed to rapid atrophy compared to the upper limbs due to the distribution of muscle fibers. 61 The rectus femoris is rich in type 2 fibers 62 while the biceps brachii usually does not show fiber-type dominance but may be more sensitive to neurogenic modifications induced by activities of daily living and cervical spondylosis than lower extremity muscles. 63 The different muscle fiber types, immobilization duration, and inclusion of the population under 65 years of age in whom sarcopenia has not yet started may have played a role in our results.…”

Validation study of ultrasonography versus computed tomography for measuring muscle mass loss in critically ill patients: CT mUS study

“…The second measurement was 24 to 96 h after admission and the third measurement 72 to 168 h after admission. All US measurements were taken simultaneously with quadriceps CT [ 3 ]. We have performed 21 measurements to assess the inter-observer correlation in performing the US and found a strong positive correlation ( r = 0.99) with good limits of agreement using the Bland and Altman analysis.…”