Utility of Pulmonary Echography for Evaluation of Patients Undergoing Orthopedic Surgery for Femur Fracture

The stratification of perioperative risk is an essential moment in the preoperative evaluation of the patient undergoing surgery especially in the setting of urgency. There is a very broad group of indexes used in the stratification of preoperative risk, like ASA-PS (American Society of Anesthesiologists Physical Status), RCRI (Revised Cardiac Risk Index) and NSQIP MICA (National Surgical Quality Improvement Program Myocardial Infarction or Cardiac Arrest). The role of some laboratory markers such as BNP has also been demonstrated. The fundamental point of all these scores is cardiocirculatory compensation. There are concerns about the value of certain preoperative exams, especially in an urgent setting. Of them all, mostly chest X-ray is questioned. Chest X-ray, indeed, needs special costs, not always short execution times and the need for X-ray exposition. Furthermore, its utility is questionable in asymptomatic patients, in which there are often no alterations to be detected. Sensibility, for Thorax x-ray, is 41% for apical flow inversion, 27% for interstitial and 6% for alveolar oedema. In chronic decompensated patients, radiographic signs of congestion have a small diagnostic accuracy, being absent in 53% of patients with capillary pulmonary pressure between 16 and 29 mmHg and in 39% of those with wedge pressure more of 30 mmHg. Pulmonary echography is a known method, that has different possible applications in diagnosis of the lung parenchymal and pleural disease. Lung is made up for 80% of water. Extravascular lung water is physiologically less than 500 ml and it increases in the case of pathology. Augmentation of this water is detected reliably by echography. B-lines are an echographic artefact that allows recognition of interstitial syndrome, having a sensibility of 93,4% and specificity of 93%. Presence of 3 or more of B-lines in 2 out of 4 fields of each hemithorax can identify a cardiac problem like pulmonary sub-oedema or chronic heart failure and i