ABSTRACT
Acute cor pulmonale, usually secondary to pulmonary hypertension induced from severe pulmonary diseases or pulmonary circulation disorders, is characterized by acute right heart dysfunction and right heart failure.Hypoxemia, hypercapnia and positive pressure ventilation can all lead to pulmonary hypertension.During the treatment of critically ill children, especially in the process of respiratory support, acute cor pulmonale should be identified as soon as possible to consider the implementation of "lung protection" and "circulation protection" with monitoring of right heart function and protection as the core.
ABSTRACT
Acute respiratory distress syndrome ( ARDS) is a devastating clinical syndrome with the condition of dyspnea,characterized by rapidly progressive hypoxemia with noncardiogenic pulmonary edema. Current therapeutic strategies are based on improving oxygenation and pulmonary compliance while minimizing ventilator-induced lung injury. However,many previous studies had found that the leading risk of ARDS patient′s death is circulatory collapse rather than pulmonary injury or hypoxemia. Additionally,acute cardiac dysfunc-tion caused by increased pulmonary vascular resistance is an important cause of circulatory failure. Besides,with the deepening of the studies,the dysfunction of lung and heart in ARDS patients,also known as severe acute cor pulmonale (ACP),has been shown to be associated with the pathophysiological process of the ARDS and could lead to the increase of right ventricular pressure load,which eventually might result in right ventricular failure. Furthermore,the inappropriate mechanical ventilation could also lead to right ventricular failure,and therefore it′s necessary to closely monitor the function of right ventricular in ARDS patients. To conclude,we will intro-duce the protective ventilation strategy of right ventricular preliminarily in this review.
ABSTRACT
Objective To explore the effect of acute respiratory distress syndrome (ARDS) induced by endotoxin on the right ventricular function in rats. Methods Sixty male Sprague-Dawley (SD) rats were randomly divided into normal saline (NS) control group and lipopolysaccharide (LPS) model group with 30 rats in each group. The rat model of ARDS was reproduced by intratracheal instillation of LPS 10 mg/kg after tracheotomy, and the rats in NS control group was intratracheally given the same volume of NS instead of LPS. The survival of rats in each group was observed. Right ventricular function was evaluated by echocardiography at 6 hours and 12 hours after instillation of LPS or NS respectively. Then the rats were sacrificed by bloodletting, and the right heart and lung tissue were harvested. The lung wet/dry weight (W/D) ratio was assessed. The pathological changes in cardiopulmonary tissue in rats were observed with hematoxylin and eosin (HE) strain, and the pathological score of lung injury was calculated. Results There was no animal death in NS control group. In LPS model group, there were 3 rats dead at 6 hours, and 4 dead at 12 hours. The pathological manifestations of lung injury were found at 6 hours after instillation of LPS, and the marked pathological changes of ARDS, such as atelectasis and hyaline membranes were observed at 12 hours. There was no obvious abnormality in the lung tissue of the NS control group. Compared with the NS control group, the 12-hour lung W/D ratio and the lung injury pathological score in the LPS model group were significantly increased (lung W/D ratio:7.69±1.02 vs. 4.14±0.48, lung injury pathological score: 8.26±2.12 vs. 1.32±0.94, both P < 0.01). Echocardiography showed that the right heart function of rats was significantly abnormal with the prolongation of LPS induction time, which showed that pulmonary arterial diameter (PAD) and right ventricular diastolic diameter (RVDd) were increased, maximum blood flow velocity of pulmonary artery (PAVmax), maximum pulmonary artery pressure gradient (PAmaxPG),pulmonary artery acceleration time (PAAT) and tricuspid annular plane systolic excursion (TAPSE) were decreased, with significant differences at 12 hours as compared with those of NS normal group [PAD (mm): 2.84±0.31 vs. 2.11±0.37, RVDd (mm): 4.18±0.71 vs. 3.17±0.40, PAVmax (mm/s): 704.00±145.13 vs. 809.59±120.48, PAmaxPG (mmHg, 1 mmHg = 0.133 kPa): 2.07±0.88 vs. 2.73±0.76, PAAT (ms): 23.80±4.87 vs. 30.01±3.02, TAPSE (mm): 2.48±0.45 vs. 3.56±0.40, all P < 0.01]. Pathological examination showed that the cardiac tissue in the LPS model group showed disorder of myocardial cells and scattered inflammatory cells at 6 hours, and cardiomyocyte degeneration, structural destruction and inflammatory cells were found at 12 hours. Conclusion ARDS induced by instillation of LPS at 12 hours causes right ventricular dysfunction in rats.
ABSTRACT
Acute respiratory distress syndrome (ARDS) is a severe respiratory condition that is characterized by rapidly progressive hypoxemia with noncardiogenic pulmonary edema.Despite the improvement of therapeutic methods,the mortality of ARDS is in the range of 40％-50％ all over the world.Some studies have shown that a significant number of patients with ARDS had acute cor pulmonale (ACP),and ACP is independently associated with the mortality of patients with ARDS,which has attracted wide attention in recent years.This paper reviewed recent related studies,summarized the prevalence,pathogenesis and diagnostic approaches of ACP in ARDS,especially echocardiography which was considered as a cornerstone for ACP diagnosis,and elucidated the beneficial effects of right ventricular protective ventilatory strategy and prone-positioning on the pulmonary vasculature and right heart,in order to provide a novel idea for the therapy of ACP in ARDS.
ABSTRACT
Acute respiratory distress syndrome (ARDS) patients experiencing protective mechanical ventilation, is associated with a marked mortality reduction. However, the incidence of acute cor pulmonale (ACP) in ARDS patients has recently been reported to range between 22% and 25%, as well as a trend for higher mortality. Therefore, the mechanical ventilation strategy is proposed, not only based on the protection of the lung, but also focused on the impact on the right ventricle function. Currently, point-of-care ultrasound has been widely practiced in a variety of clinical setting, which plays more and more important role in the early detection and management of ARDS and its complications. A retrospective study concerning the incidence, pathophysiology and risk factors for ACP patients in ARDS was done to analysis the application of lung ultrasound and echocardiography combined with lung ultrasound in clinical hemodynamics monitoring, and so as to optimize the ventilation setting to protect the function of lung and right ventricle. Further exploration of effective improvement of the pulmonary vascular and right ventricle function the goal-directed ultrasound approach, and the diagnosis and treatment flow is expected.