Intensive care unit (ICU) acquired muscle weakness (ICUAW) is a clinically detected condition characterized by diffuse, symmetric weakness involving the limbs and respiratory muscles Patients have different degrees of limb muscle weakness and are dependent on a ventilator, while the facial muscles are spared. Diagnosis of ICUAW requires that no plausible etiology other than critical illness be identified, and thus, other causes of acute muscle weakness is excluded. One major diagnostic criterion is that ICUAW is detected after the onset of critical illness. ICUAW is a multifactorial disease the risk factors include female gender duration of mechanical ventilation, glucocorticoids therapy, persistent hyperglycemia, multiorgan system failure, sepsis, use of neuromuscular blockers during the ICU stay2,3,1 ICUAW is a clinically relevant complication during the acute stage of disease and after discharge from the acute-care hospital. In the ICU, severe muscle weakness is independently associated with prolonged mechanical ventilation, ICU stays, hospital stays, and increased mortality Patients developing weakness during the ICU stay have reduced quality of life and increased mortality 1 year after ICU discharge.
A diagnosis of ICUAW is achieved by manually testing the muscle strength using the Medical Research Council scale. MRC muscle strength is assessed in 12 muscle groups, (wrist flexion, forearm flexion, shoulder abduction, ankle dorsiflexion, knee extension, and hip flexion), the total score ranges from 0 (complete paralysis) to 60 (normal muscle strength) a summed score below 48/60 designates ICUAW or significant weakness, and an MRC score below 36/48 indicates severe weakness But this requires full patient cooperation and a fully conscious patient which is not always the case in ICU because of the use of sedation. Respiratory muscles are often involved in ICUAW. The diaphragm is a major respiratory muscle accounting for 80% of inspiratory function assessment of diaphragm weakness is a useful tool in assessing ICUAW. Bedside ultrasonography, which is already crucial in several aspects of critical illness has been recently proposed as a simple, non-invasive method of quantification of diaphragmatic contractile activity. Ultrasound can be used to determine diaphragm excursion using M mode Ultrasonography of the diaphragm may be useful in identifying patients with diaphragmatic weakness which may lead to prolonged weaning Diaphragmatic excursion using M mode can be measured in both hemidiaphragm, during quiet breathing, deep breathing, and voluntary sniff. Normal values of excursion vary with age and gender position of the patient, In supine position. The lower limit values for the right hemidiaphragm were close to 1.1 cm for women and 1.2 cm for men during quiet breathing, 1.6 cm for women and 1.8 cm for men during voluntary sniffing, and 3.7 cm for women and 4.7 cm for men during deep breathing7 Not all patients who are weaned in ICU off ventilator have diaphragm weakness, they may have poor muscle power or MRC score. in this study, we plan to find a correlation between diaphragmatic excursion using ultrasound with MRC sum score which has not been done in earlier studies. We hypothesize that the degree of respiratory weakness correlates with the degree of limb weakness measured using the MRC sum score. And we can use diaphragmatic excursion to predict the presence of ICUAW. |