The Significance Of Rectus Femoris Ultrasonography In Nutritional Status Assessment Of Critically Ill Patients

Objective:Critically ill patients are severely ill,acute catabolic state in the acute phase,combined with protective constraint,lack of exercise and other reasons,a large amount of protein consumption and muscle loss are difficult to avoid.Early rapid muscle loss leads to skeletal muscle atrophy,muscle strength decline and muscle function impaired,which is related to prolonged hospital stay and increased mortality and complications.Ultrasonography can qualitatively and quantitatively measure skeletal muscle,record the changes of skeletal muscle in critically ill patients,which is non-invasive,convenient and rapid.The purpose of this study was to assess the value of ultrasound measurement of the rectus femoris cross-sectional area to monitor the nutritional status and prognosis of critically ill patients.Method:The study subjects were adult critically ill patients who stayed in the Intensive Care Unit(ICU)of Hebei General Hospital for 4days or more,hospitalized from July 1,2018 to December 31,2018.At the same time,the bedside ultrasound measurement of the rectus femoris cross-sectional area(RF-CSA)was used by a specially trained Severe physician,expressed in square centimeters(cm~2).RF-CSA was ultrasound measured on the 1th,4th and 7th day of the ICU.The age,gender,APACHE II score,admission diagnosis,length of ICU stay,length of hospital stay,ICU mortality,hospital mortality,nutritional support in the ICU,bicarbonate concentration,oxygenation index,and mean hemoglobin concentration at the time of admitted to the ICU were recorded.Indirect calorimetry was used to evaluate whether the feeding of the patients was up to standard.The changes of RF-CSA were assessed by repeated measures analysis of variance,and multiple stepwise linear regression analysis was used to analyze the factors affecting the change of 7th day RF-CSA.Logistic regression was used to analyze the relationship between RF-CSA of day 1 admitted to ICU and RF-CSA changes and hospital mortality.Other independent variables included age,gender,acute physiologic and chronic health(APACHEII)score,and admission diagnosis(postresuscitation,respiratory dysfunction,sepsis,cerebrovascular,metabolic/Renal,heat stroke,cardiovascular,trauma,digestive system disease,postsurgery).The relationship between RF-CSA changes on the4th and 7th day and length of ICU stay and length of hospital stay was analyzed.The change of RF-CSA on day 4 was analyzed using ROC curve,and the cut-off value predicting ICU mortality was calculated.Results:The study included 53 patients,12 women,and 41 men.The mean age is 67 years old,and nutritional support was adequate for all patients.On the first day of ICU,RF-CSA of women was lower than that of men(2.9225±0.862 cm~2,4.3315±1.76335 cm~2;P=0.002).On day 4,RF-CSA decreased by 4.70%,95%CI(4.23%-5.18%),on day 7 decreased by 11.05%,95%CI(9.94%-12.16%),and the change was not related to gender.The APACHEII score and the oxygenation index affected the change of RF-CSA on day 7.The change of RF-CSA on day 7 affected the duration of ICU stay and was not related to the length of hospital stay.The change of RF-CSA on day 4 and APACHEII score were independent risk factors for ICU mortality,and the cut-off value for predicting death was5.39%.Conclusion:Ultrasound is an effective and practical tool for measuring skeletal muscle,which can record muscle mass daily in the intensive care unit.In the early stage of critical illness,although the energy supply is adequate,skeletal muscle area also decreases,and ultrasound can measure skeletal muscle changes early.The APACHEII score and oxygenation index affected the change of rectus muscle area on the 7th day.Muscle atrophy can prolong ICU stay in critically ill patients.Changes in the cross-sectional area of the rectus femoris are independent risk factors for death in critically ill patients.