Focused ultrasound is the next step in perioperative care

Abstract

In this issue of the Journal, two different investigators report the use of bedside ultrasound for focused cardiac examination as well as for focused thoracic and abdominal examinations in patients undergoing non-cardiac surgery. These ultrasound observations led to a change in patient management, and it is expected that more widespread use of this tool in our practice will likely have a significant impact on perioperative care. This paradigm change implies that consideration should be given to incorporating an ultrasound curriculum within our anesthesiology training programs. The first case involves a previously healthy 29-yr-old pregnant woman who developed preeclampsia complicated by HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome. Following Cesarean delivery, the patient remained anuric and was transferred to the intensive care unit. A bedside cardiac ultrasound was performed using a validated pulsed wave tissue Doppler technique to estimate filling pressures and evaluate cardiac function. The patient was found to be responsive to passive leg raising and fluid therapy, and ultrasound confirmed the absence of fluid overload; however, a few hours later, she was found to be anemic. At that point, abdominal ultrasound was used to diagnose an intra-abdominal hematoma. Based on these findings, a decision was made to transfuse blood and explore the abdomen surgically. Postoperatively, the patient became hypoxic, and a repeated lung ultrasound showed comet-tail artifacts of B-lines, which is suggestive of an alveolar-interstitial syndrome. The absence of elevated filling pressure on cardiac ultrasound suggested non-cardiogenic pulmonary edema and the possibility of acute respiratory distress syndrome. The other case involves a 58-yr-old man who was scheduled for elective nasal polyp excision. The patient was known to have aortic stenosis and was ‘‘cleared’’ preoperatively by a cardiologist and a cardiac surgeon. A preoperative anesthesia evaluation of cardiac function with bedside ultrasound revealed an unsuspected large pericardial effusion with signs of pericardial tamponade and right atrial and right ventricular collapse. The case was cancelled and the patient underwent percutaneous pericardial drainage. The clinical presentation and pericardial fluid analysis led to the diagnosis of ChurgStrauss syndrome complicated by progressive pericardial effusion. The patient was discharged from hospital several days later, and his nasal polyps were treated medically. These two cases effectively illustrate the gradual integration of bedside ultrasound as a point-of-care examination performed by the anesthesiologist for conditions that are not uncommon in the perioperative setting. Ultrasound was used in a goal-oriented approach to answer a specific question, and it involved more than solely examination of the heart. As anesthesiologists and critical care physicians, we strive to maintain adequate oxygen delivery; ultrasound can play a role in identifying A. Denault, MD, PhD (&) Department of Anesthesia, Montreal Heart Institute, 5000 Belanger Street, Montreal, QC H1S 1T8, Canada e-mail: andre.denault@gmail.com