Diaphragmatic regional displacement assessed by ultrasound and correlated to subphrenic organ movement in the critically ill patients-an observational study

IntroductionThe objectives of the study are to identify the most reliably imaged regions of the diaphragm, to evaluate the correlation of movement between different parts of each hemidiaphragm, and to assess the agreement between liver or spleen displacement and movement of the ipsilateral hemidiaphragm.MethodsImages of the diaphragm, liver, and spleen were obtained using 2-dimensional ultrasound. Acceptable agreement between regions of the diaphragm, liver, and spleen was defined as an absence of fixed or proportional bias using Deming regression analysis and limits of agreement of 2 SDs of the difference less than 30% of the mean value.ResultsWe included 90 critically ill patients. The medial (87%) and middle (73%) regions of the right hemidiaphragm, liver (87.7%), and spleen (81%) and medial (71%) and middle regions (51%) of the left hemidiaphragm were most frequently imaged. In nonintubated patients, acceptable agreement was present for comparisons of the left middle and medial, right middle and medial, and left middle regions and spleen displacement. In intubated patients and in all patients when combined, acceptable agreement was only present for comparisons of the left middle and medial and right middle and medial regions of the diaphragm. Acceptable agreement was not present for intubated and all patients for diaphragmatic and solid organ movement.ConclusionThe diaphragm medial part is visualized in the majority of studied patients. The medial and middle thirds may be used interchangeably to assess hemidiaphragm movement. Acceptable agreement does not exist for diaphragm and solid organ movement, other than for the left middle region and the spleen.