Echocardiography in the intensive care unit: An essential tool for diagnosis, monitoring and guiding clinical decision-making.

In the last years, new trends on patient diagnosis for admission in cardiac intensive care unit (CICU) have been observed, shifting from acute myocardial infarction or acute heart failure to non-cardiac diseases such as sepsis, acute respiratory failure or acute kidney injury. Moreover, thanks to the advances in scientific knowledge and higher availability, there has been increasing use of positive pressure mechanical ventilation which has its implications on the heart. Therefore, there is a growing need for Cardiac intensivists to quickly, noninvasively and repeatedly evaluate various hemodynamic conditions and the response to therapy. Transthoracic critical care echocardiography (CCE) currently represents an essential tool in CICU, as it is used to evaluate biventricular function and complications following acute coronary syndromes, identify the mechanisms of circulatory failure, acute valvular pathologies, tailoring and titrating intravenous treatment or mechanical circulatory support. This could be completed with trans-esophageal echocardiography (TOE), advanced echocardiography and lung ultrasound to provide a thorough evaluation and monitoring of CICU patients. However, CCE could sometimes be challenging as the acquisition of good-quality images is limited by mechanical ventilation, suboptimal patient position or recent surgery with drains on the chest. Moreover, there are some technical caveats that one should bear in mind while performing CCE in order to optimize its use and avoid misleading findings. The aim of this review is to highlight the key role of CCE, providing an updated overview of its main applications and possible pitfalls in order to facilitate its use in CICU for clinical decision-making.

Pros and Cons of Different Types of Mechanical Circulatory Support Device in Case of Postinfarction Ventricular Septal Defect.

Postinfarction ventricular septal defect (VSD) is an uncommon but almost lethal complication. The optimal timing for VSD repair is matter of debate, and mechanical circulatory support (MCS) devices allow to hemodynamically support the patient and postpone the VSD closure until myocardial tissue is less friable and the patient's condition is less compromised. However, data are lacking to guide the choice of the best types of MCS in case of VSD. We present a case of a large postinfarction VSD and the use of central venoarterial extracorporeal membrane oxygenation support to stabilize the patient until the VSD surgical repair. This case offers the opportunity to revise the indications and characteristics of different MCS, highlighting pros and cons of each one.

The contribution of left heart disease in COPD patients with pulmonary hypertension.

BACKGROUND: Pulmonary hypertension (PH), regardless of its etiology, is associated with an impaired outcome in patients with chronic obstructive pulmonary disease (COPD). The aim of our study was to determine the incidence, cause, and effect of PH as detected by echocardiography in COPD patients. METHODS: Patients with confirmed COPD of any stage were evaluated by echocardiography for the likelihood of PH according to the proposed criteria. Patients with possible/likely to have PH underwent right heart catheterization, upon agreement, to confirm the presence, severity, and cause of PH. RESULTS: Of 91 patients, 39 were in stable condition (group A) and 52 with COPD exacerbation (group B). Group B patients presented with PH and left ventricular diastolic dysfunction more often than group A patients. One of two fulfilled the criteria for possible/likely PH. The incidence of likely/possible PH was significantly higher in group B. Nineteen group B patients with likely/possible PH underwent RHC, and PH was confirmed in 15 cases and in 73.3% was associated with left heart disease. The presence of possible/likely PH was associated with a statistically significant increase in mortality compared to those with unlikely PH. CONCLUSIONS: The use of echocardiographic criteria for the presence of PH is adequate for the screening of COPD patients. Patients with acute exacerbation of COPD and possible/likely PH demonstrate worse mortality compared to patients unlikely to have PH.

Impaired phospholipases A2production by stimulated macrophages from patients with acute respiratory distress syndrome.

The aim of this study was to investigate whether early phase of acute respiratory distress syndrome (ARDS) is associated with changes in immune response, either systemic or localized to the lung. ARDS and control mechanically ventilated patients, as well as healthy volunteers were studied. Alveolar macrophages (AMΦ) and blood monocytes (BM) were treated ex vivo with lipopolysaccharide (LPS), interferon-γ (IFNγ), and surfactant. Phospholipase A2 (PLA2) activity and TLR4 expression were evaluated as markers of cell response. AMΦ from ARDS patients did not respond upon treatment with either LPS or IFN-γ by inducing PLA2 production. On the contrary, upon stimulation, in control patients the intracellular PLA2, (mainly cPLA2) levels were increased, but secretion of PLA2 (mainly sPLA2-IIA) was observed only after treatment with LPS. Surfactant suppressed PLA2 production in cells from both groups of patients. Increased relative changes of total PLA2 activity and an upregulation of TLR4 expression upon stimulation was observed in BM from primary ARDS, control patients and healthy volunteers. In BM from secondary ARDS patients, however, no PLA2 induction was observed, with a concomitant down-regulation of TLR4 expression. Cytosolic PLA2, its activated form, p-cPLA2, and sPLA2-IIA were the predominant PLA2 types within the cells, while extracellularly only sPLA2-IIA was identified. These results support the concept of down-regulated innate immunity in early ARDS that is compartmentalized in primary and systemic in secondary ARDS. PLA2 isoforms could serve as markers of the immunity status in ARDS. Finally, our data highlight the role of surfactant in controlling inflammation.

Lung and 'end organ' injury due to mechanical ventilation in animals: comparison between the prone and supine positions.

INTRODUCTION: Use of the prone position in patients with acute lung injury improves their oxygenation. Most of these patients die from multisystem organ failure and not from hypoxia, however. Moreover, there is some evidence that the organ failure is caused by increased cell apoptosis. In the present study we therefore examined whether the position of the patients affects histological changes and apoptosis in the lung and 'end organs', including the brain, heart, diaphragm, liver, kidneys and small intestine. METHODS: Ten mechanically ventilated sheep with a tidal volume of 15 ml/kg body weight were studied for 90 minutes. Five sheep were placed in the supine position and five sheep were placed in the prone position during the experiment. Lung changes were analyzed histologically using a semiquantitative scoring system and the extent of apoptosis was investigated with the TUNEL method. RESULTS: In the supine position intra-alveolar hemorrhage appeared predominantly in the dorsal areas, while the other histopathologic lesions were homogeneously distributed throughout the lungs. In the prone position, all histological changes were homogeneously distributed. A significantly higher score of lung injury was found in the supine position than in the prone position (4.63 +/- 0.58 and 2.17 +/- 0.19, respectively) (P < 0.0001). The histopathologic changes were accompanied by increased apoptosis (TUNEL method). In the supine position, the apoptotic index in the lung and in most of the 'end organs' was significantly higher compared with the prone position (all P < 0.005). Interestingly, the apoptotic index was higher in dorsal areas compared with ventral areas in both the prone and supine positions (P < 0.003 and P < 0.02, respectively). CONCLUSION: Our results suggest that the prone position appears to reduce the severity and the extent of lung injury, and is associated with decreased apoptosis in the lung and 'end organs'.

Biochemical parameters of bronchoalveolar lavage fluid in fat embolism.

OBJECTIVE: To identify diagnostic markers distinguishing between acute lung injury/acute respiratory distress syndrome (ALI/ARDS) due to fat embolism syndrome (FES) and that due to other causes, and to investigate whether phospholipase A2 and platelet-activating factor (PAF) play a role in the pathogenesis of ALI due to FES. DESIGN AND SETTING: A prospective study in a 14-bed ICU. PATIENTS: We studied 13 patients with FES, 11 with ALI/ARDS from other causes (6 without trauma, ALI/ARDS group 1; 7 with trauma, ALI/ARDS group 2) and 5 without cardiopulmonary disease. MEASUREMENTS AND RESULTS: We compared broncholveolar lavage (BAL) fluid alterations in the respective groups. Total BAL protein in FES group was significantly higher compared to in ALI/ARDS group 1 and controls but ALI/ARDS group 2. Higher total phospholipids were found than in other groups. The alterations in individual phospholipid classes were similar to those in ALI/ARDS patients. However, total cholesterol, lipid esters, and monoglycerides were significantly higher in FES than in other groups. The level of PAF in FES was significantly higher and there was an inverse correlation between PAF and PAF-acetylhydrolase. Phospholipase A2 activity was significantly higher in both FES and ALI/ARDS groups than in control. CONCLUSIONS: The levels of neutral lipids and especially cholesterol and cholesterol esters in BAL can be used to distinguish patients with FES from ALI/ARDS due to other predisposing factors. Phospholipase A(2) may be involved in the development, and PAF-acetylhydrolase in the downregulation of inflammation in FES.