Detecting unilateral phrenic paralysis by acoustic respiratory analysis

The consequences of phrenic nerve paralysis vary from a considerable reduction in respiratory function to an apparently normal state. Acoustic analysis of lung sound intensity (LSI) could be an indirect non-invasive measurement of respiratory muscle function, comparing activity on the two sides of the thoracic cage. Lung sounds and airflow were recorded in ten males with unilateral phrenic paralysis and ten healthy subjects (5 men/5 women), during progressive increasing airflow maneuvers. Subjects were in sitting position and two acoustic sensors were placed on their back, on the left and right sides. LSI was determined from 1.2 to 2.4 L/s between 70 and 2000 Hz. LSI was significantly greater on the normal (19.3±4.0 dB) than the affected (5.7±3.5 dB) side in all patients (p = 0.0002), differences ranging from 9.9 to 21.3 dB (13.5±3.5 dB). In the healthy subjects, the LSI was similar on both left (15.1±6.3 dB) and right (17.4±5.7 dB) sides (p = 0.2730), differences ranging from 0.4 to 4.6 dB (2.3±1.6 dB). There was a positive linear relationship between the LSI and the airflow, with clear differences between the slope of patients (about 5 dB/L/s) and healthy subjects (about 10 dB/L/s). Furthermore, the LSI from the affected side of patients was close to the background noise level, at low airflows. As the airflow increases, the LSI from the affected side did also increase, but never reached the levels seen in healthy subjects. Moreover, the difference in LSI between healthy and paralyzed sides was higher in patients with lower FEV1 (%). The acoustic analysis of LSI is a relevant non-invasive technique to assess respiratory function. This method could reinforce the reliability of the diagnosis of unilateral phrenic paralysis, as well as the monitoring of these patients.Peer ReviewedPostprint (published version

Contemporary use of arterial and venous conduits in coronary artery bypass grafting:anatomical, functional and clinical aspects

Although the benefits of using the left internal mammary artery to bypass the left anterior descending artery (LAD) have been extensively ascertained, freedom from major cardiovascular events and survival after coronary artery bypass grafting (CABG) also correlate with the completeness of revascularisation. Hence, careful selection of the second-best graft conduit is crucial for CABG success. The more widespread use of saphenous vein grafts contrasts with the well-known long-term efficacy of multiple arterial grafting, which struggles to emerge as the procedure of choice due to concerns over increased technical difficulties and higher risk of postoperative complications. Conduit choice is at the discretion of the operator instead of being discussed by the heart team, where cardiologists are not usually engaged in such decisions due to a hypothetical lack of technical knowledge. Furthermore, according to the ESC/EACTS guidelines, traditional CABG remains the gold standard for multi-vessel coronary artery disease with complex LAD stenosis, but hybrid procedures using percutaneous coronary intervention for non-LAD targets could combine the best of two worlds. With the aim of raising the cardiologist’s awareness of the surgical treatment options, we provide a comprehensive overview of the anatomical, functional and clinical aspects guiding the decision-making process in CABG strategy

Anatomy and neuro-pathophysiology of the cough reflex arc

<p>Abstract</p> <p>Coughing is an important defensive reflex that occurs through the stimulation of a complex reflex arc. It accounts for a significant number of consultations both at the level of general practitioner and of respiratory specialists. In this review we first analyze the cough reflex under normal conditions; then we analyze the anatomy and the neuro-pathophysiology of the cough reflex arc. The aim of this review is to provide the anatomic and pathophysiologic elements of evaluation of the complex and multiple etiologies of cough.</p