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Objectives: Although pericardial effusions (PE) and pleural effusions (PLE) may lead to life-threatening respiratory and circulatory deterioration following open heart surgery the postoperative frequency is not fully recognized. The diagnosis is typically based on ultrasonography, X-ray or computer tomography and often disclosed when circulatory collapse is evident. Point-of-care (POC) ultrasonography protocols constitute a noninvasive evaluation of the cardiopulmonary status. We hypothesized that POC ultrasonography could diagnose unknown PE and PLE., Design: Patients scheduled for open heart surgery were eligible for inclusion. Baseline evaluation including POC examination and dyspnea score was performed one day prior to surgery and repeated on the 4th and 30th postoperative day., Results: Eighty patients were included and complete follow-up was 80%. Thirteen patients (19%) had PE on the 4th day postsurgery and 19 patients (30%) had PE on the 30th day. Ultrasonography facilitated change in management in one patient with PE requiring drainage. Forty-nine patients (70%) had PLE on the 4th day following surgery and 19 patients (30%) had PLE on the 30th postoperative day. Ultrasonography facilitated a change in management in seven patients with PLE requiring drainage., Conclusion: POC ultrasonography detected pathology, otherwise undisclosed, and was responsible for a change in management in a considerable number of cases.

Background: Ultrasonography of the cardiovascular system is pivotal for hemodynamic assessment. Diastolic function is evaluated with a combination of tissue Doppler (e' and a') and pulsed Doppler (E and A) measures of transmitral- and mitral valve annuli velocities. However, accurate echocardiographic evaluation in the intensive care unit or perioperative setting is contingent on relative resistance to positive pressure ventilation and changes in preload. This study aimed to evaluate the effects of positive end-expiratory pressure (PEEP) and positioning on echocardiographic measures of diastolic function., Methods: The study was a prospective, randomized, crossover study. Cardiac surgery patients with ejection fraction greater than 45% and averaged e' of 9 or more were included. Postoperatively, anesthetized patients were randomized into six combinations of PEEP (0, 6, 12 cm H2O) and positions (horizontal, Trendelenburg). At each combination, e' (primary endpoint), a', E, and A were obtained with transesophageal echocardiography along with left ventricular area. Image analysis was performed blinded to the protocol., Results: Thirty patients completed the study. PEEP decreased lateral e' from 6.6±3.6 to 5.3±3.0 cm/s (P<0.001) in the horizontal position and from 7.4±4.2 to 6.5±3.3 cm/s (P<0.001) in Trendelenburg. Similar results were found for septal e', a' bilaterally and transmitral pulsed Doppler measures, and PEEP decreased left ventricular area. E/A, E/e', and e'/a' remained unaffected by PEEP and positioning., Conclusions: When evaluating diastolic function by echocardiography, the levels of PEEP and its effect on ventricular area have to be taken into account. In addition, this study dissuades the use of E/e' for tracking changes in left ventricular filling pressures in cardiac surgery patients.

Objectives: The myocardial recovery time following on-pump cardiac surgery remains uncertain. Global peak longitudinal strain is a sensitive measure of endocardial function which is most susceptible to ischaemia. We aimed to evaluate changes in global peak longitudinal strain up to 6 months after surgery and to compare initial changes with alterations in troponin T. Secondarily, we aimed to describe perioperative changes in strain of the inter-ventricular septum when compared with reference segments., Methods: Patients scheduled for coronary bypass, aortic valve replacement or combination procedures were enrolled. Echocardiography was performed on the day before surgery, the day after surgery, 4 days after surgery, 30 days after surgery and 6 months after surgery. Troponin T was measured 3, 16 and 24 h following procedure., Results: Forty patients were enrolled and one was later excluded. Global peak longitudinal strain decreased from -14.5 ± 3.33% preoperatively to -9.98 ± 3.09% and -10.57 ± 3.16% on the first and fourth postoperative day, respectively. Global strain was still reduced on the 30th postoperative day, but had returned to preoperative values 6 months after surgery. Absolute values and relative changes in global strain did not correlate with postoperative peak troponin T measurements. Strain of the inter-ventricular septum was unaffected by surgery as opposed to reference segments, although septal displacement in the longitudinal direction decreased from 12.0 ± 3.75 mm preoperatively to 3.58 ± 4.22 mm 4 days after surgery., Conclusions: Global peak longitudinal strain was reduced for at least 30 days after on-pump cardiac surgery and seems to represent a more sensitive marker of myocardial function than ejection fraction. The decrease in global strain was not reflected in troponin T measurements. The visual, echocardiographic impression of septal dysfunction may be a translational phenomenon, as septal strain was unaffected by surgery.