Early Six-Minute Walk Test May Predict Midterm Outcomes Following Coronary Artery Bypass Grafting

ABSTRACT Objective: This study aims to investigate the ability of the six-minute walk distance (6MWD) as a prognostic marker for midterm clinical outcomes three months after coronary artery bypass grafting (CABG), to identify possible predictors of fall in 6MWD in the early postoperative period, and to establish the percentage fall in early postoperative 6MWD, considering the preoperative baseline as 100%. Methods: A prospective cohort of patients undergoing elective CABG were included. The percentage fall in 6MWD was assessed by the difference between preoperative and postoperative day (POD) five. Clinical outcomes were evaluated three months after hospital discharge. Results: There was a significant decrease in 6MWD on POD5 compared with preoperative baseline values (percentage fall of 32.5±16.5%, P<0.0001). Linear regression analysis showed an independent association of the percentage fall of 6MWD with cardiopulmonary bypass (CPB) and preoperative inspiratory muscle strength. Receiver operating characteristic curve analysis revealed that the best cutoff value of percentage fall in 6MWD to predict poorer clinical outcomes at three months was 34.6% (area under the curve = 0.82, sensitivity = 78.95%, specificity = 76.19%, P=0.0001). Conclusion: This study indicates that a cutoff value of 34.6% in percentage fall of 6MWD on POD5 was able to predict poorer clinical outcomes at three months of follow-up after CABG. Use of CPB and preoperative inspiratory muscle strength were independent predictors of percentage fall of 6MWD in the postoperative period. These findings further support the clinical application of 6MWD and propose an inpatient preventive strategy to guide clinical management over time.

Cardiovascular involvement in COVID-19: not to be missed

Abstract In December 2019, a striking appearance of new cases of viral pneumonia in Wuhan led to the detection of a novel coronavirus (SARS-CoV2). By analyzing patients with severe manifestations, it became apparent that 20 to 35% of patients who died had preexisting cardiovascular disease. This finding warrants the important need to discuss the influence of SARS-CoV2 infection on the cardiovascular system and hemodynamics in the context of clinical management, particularly during mechanical ventilation. The SARS-CoV2 enters human cells through the spike protein binding to angiotensin-converting enzyme 2 (ACE2), which is important to cardiovascular modulation and endothelial signaling. As ACE2 is highly expressed in lung tissue, patients have been progressing to acute respiratory injury at an alarming frequency during the Coronavirus Disease (COVID-19) pandemic. Moreover, COVID-19 leads to high D-dimer levels and prothrombin time, which indicates a substantial coagulation disorder. It seems that an overwhelming inflammatory and thrombogenic condition is responsible for a mismatching of ventilation and perfusion, with a somewhat near-normal static lung compliance, which describes two types of pulmonary conditions. As such, positive pressure during invasive mechanical ventilation (IMV) must be applied with caution. The authors of this review appeal to the necessity of paying closer attention to assess microhemodynamic repercussion, by monitoring central venous oxygen saturation during strategies of IMV. It is well known that a severe respiratory infection and a scattered inflammatory process can cause non-ischemic myocardial injury, including progression to myocarditis. Early strategies that guide clinical decisions can be lifesaving and prevent extended myocardial damage. Moreover, cardiopulmonary failure refractory to standard treatment may necessitate the use of extreme therapeutic strategies, such as extracorporeal membrane oxygenation.

A dedicated stitch to allow early safe mobilization avoiding drain-induced heart injury

Abstract Placement of a mediastinal drain is a routine procedure following heart surgery. Postoperative bed rest is often imposed due to the fear of potential risk of drain displacement and cardiac injury. We developed an encapsulating stitch as a feasible, effective and low-cost technique, which does not require advanced surgical skills for placement. This simple, novel approach compartmentalizes the drain allowing for safe early mobilization following cardiac surgery.

Early open-lung ventilation improves clinical outcomes in patients with left cardiac dysfunction undergoing off-pump coronary artery bypass: a randomized controlled trial

Abstract Objective: To compare pulmonary function, functional capacity and clinical outcomes amongst three groups of patients with left ventricular dysfunction following off-pump coronary artery bypass, namely: 1) conventional mechanical ventilation (CMV); 2) late open lung strategy (L-OLS); and 3) early open lung strategy (E-OLS). Methods: Sixty-one patients were randomized into 3 groups: 1) CMV (n=21); 2) L-OLS (n=20) initiated after intensive care unit arrival; and 3) E-OLS (n=20) initiated after intubation. Spirometry was performed at bedside on preoperative and postoperative days (PODs) 1, 3, and 5. Partial pressure of arterial oxygen (PaO2) and pulmonary shunt fraction were evaluated preoperatively and on POD1. The 6-minute walk test was applied on the day before the operation and on POD5. Results: Both the open lung groups demonstrated higher forced vital capacity and forced expiratory volume in 1 second on PODs 1, 3 and 5 when compared to the CMV group (P<0.05). The 6-minute walk test distance was more preserved, shunt fraction was lower, and PaO2 was higher in both open-lung groups (P<0.05). Open-lung groups had shorter intubation time and hospital stay and also fewer respiratory events (P<0.05). Key measures were significantly more favorable in the E-OLS group compared to the L-OLS group. Conclusion: Both OLSs (L-OLS and E-OLS) were able to promote higher preservation of pulmonary function, greater recovery of functional capacity and better clinical outcomes following off-pump coronary artery bypass when compared to conventional mechanical ventilation. However, in this group of patients with reduced left ventricular function, initiation of the OLS intra-operatively was found to be more beneficial and optimal when compared to OLS initiation after intensive care unit arrival.

Pleural subxyphoid drain confers better pulmonary function and clinical outcomes in chronic obstructive pulmonary disease after off-pump coronary artery bypass grafting: a randomized controlled trial / Dreno pleural subxifoide confere melhor função pulmonar e resultados clínicos na doença pulmonar obstrutiva crônica após cirurgia de revascularização miocárdica sem circulação extracorpórea: ensaio clínico controlado e randomizado

Objective: To evaluate the lung function and clinical outcome in severe chronic obstructive pulmonary disease in patients undergoing off-pump coronary artery bypass grafting with left internal thoracic artery graft, comparing the pleural drain insertion in the intercostal versus subxyphoid region. Methods: A randomized controlled trial. Chronic obstructive pulmonary disease patients were randomized into two groups according pleural drain site: II group (n=27) - pleural drain in intercostal space; SI group (n=29) - pleural drain in the subxyphoid region. Spirometry values (Forced Vital Capacity - and Forced expiratory volume in 1 second) were obtained on preoperative and 1, 3 and 5 postoperative days. Chest x-ray from preoperative until postoperative day 5 (POD5) was performed for monitoring respiratory events, such as atelectasis and pleural effusion. Pulmonary shunt fraction and pain score was evaluate preoperatively and on postoperative day 1. Results: In both groups there was a significant decrease of the spirometry values (Forced Vital Capacity and Forced expiratory volume in 1 second) until POD5 (P<0.05). However, when compared, SI group presented less decrease in these parameters (P<0.05). Pulmonary shunt fraction was significantly lower in SI group (P<0.05). Respiratory events, pain score, orotracheal intubation time and postoperative length of hospital stay were lower in the SI group (P<0.05). Conclusion: Subxyphoid pleural drainage in severe Chronic obstructive pulmonary disease patients determined better preservation and recovery of pulmonary capacity and volumes with lower pulmonary shunt fraction and better clinical outcomes on early postoperative off-pump coronary artery bypass grafting. .

Objetivo: Avaliar a função pulmonar e os resultados clínicos em pacientes com doença pulmonar obstrutiva crônica grave submetidos à cirurgia de revascularização do miocárdio sem circulação extracorpórea, com enxerto da artéria torácica interna esquerda, comparando a inserção do dreno pleural intercostal versus subxifoide. Métodos: Estudo clínico, controlado e randomizado. Pacientes com doença pulmonar obstrutiva crônica foram randomizados em dois grupos de acordo com a posição do dreno pleural: grupo II (n=27) - dreno pleural intercostal; grupo IS (n=29) - dreno pleural na região subxifóide. Os valores espirométricos (Capacidade Vital Forçada e Volume expiratório forçado no 1 segundo) foram obtidos no pré-operatório, e no 1º, 3º e 5º dias de pós-operatório. Foi realizada radiografia de tórax no préoperatório até o 5º dia pós-operatório (5PO) para monitoração de eventos respiratórios, como atelectasia e derrame pleural. A fração de shunt pulmonar e a escala de dor foram avaliadas no 1º dia pós-operatório. Resultados: Em ambos os grupos houve queda significativa dos valores espirométricos (Capacidade Vital Forçada e Volume expiratório forçado no 1 segundo) até o 5PO (P<0.05), porém, quando comparados, o grupo IS apresentou menor queda destes parâmetros (P<0.05). A fração de shunt pulmonar foi significativamente menor no grupo IS (P<0.05). Os eventos respiratórios, escala da dor, tempo de intubação orotraqueal e dias internação hospitalar no pós-operatório foram menores no grupo IS (P<0.05). Conclusão: Drenagem pleural subxifoide em pacientes com doença pulmonar obstrutiva crônica grave determinou melhor preservação e recuperação dos volumes e capacidades pulmonares, com menor fração de shunt pulmonar e melhores resultados clínicos no pós-operatório precoce de cirurgia de revascularização do miocárdio sem circulação extracorpórea. .