Nonlinear N - Compartments model of respiratory mechanics considering viscoelasticity, inertia and surface tension properties.

Respiratory biomechanics constitutes an important topic in clinical practice. Different strategies like mathematical models have been implemented to understand and replicate scenarios allowing deeper analysis. In this paper, a nonlinear N - compartments model is presented, allowing to represent the lung in a heterogeneous way.

Computational model of trachea-alveoli gas movement during spontaneous breathing.

A computational model of the transport of gases involved in spontaneous breathing, from the trachea inlet to the alveoli was developed for healthy patients. Convective and diffusive transport mechanisms were considered simultaneously, using a diffusion coefficient (D) that has considered the four main species of gases present in the exchange carried out by the human lung, nitrogen (N), oxygen (O), carbon dioxide (CO) and water vapor (HO). A Matlab® script was programmed to simulate the trachea-alveolus gas exchange model under three respiratory frequencies: 12, 24 and 40 breaths per minute (BPM), each with three diaphragmatic movements of 2 cm, 4 cm, and 6 cm.

Low-power system for the acquisition of the respiratory signal of neonates using diaphragmatic electromyography.

Introduction: An apnea episode is defined as the cessation of breathing for ≥15 seconds or as any suspension of breathing accompanied by hypoxia and bradycardia. Obtaining information about the respiratory system in a neonate can be accomplished using electromyography signals from the diaphragm muscle.

Objective: The purpose of this paper is to illustrate a method by which the respiratory and electrocardiographic signals from neonates can be obtained using diaphragmatic electromyography.

Dual-pump support in the inferior and superior vena cavae of a patient-specific fontan physiology.

The implementation of simultaneous mechanical cavopulmonary assistance having blood pumps located in both of the vena cavae is investigated as an approach to treating patients with an ailing Fontan physiology. Identical intravascular blood pumps are employed to model the hemodynamic support of a patient-specific Fontan. Pressure flow characteristics, energy gain calculations, and blood damage analyses are assessed for each model.

A viable therapeutic option: mechanical circulatory support of the failing Fontan physiology.

A blood pump specifically designed to augment flow from the great veins through the lungs would ameliorate the poor physiology of the failing univentricular circulation and result in a paradigm shift in the treatment strategy for Fontan patients. This study is the first to examine mechanical cavopulmonary assistance with a blood pump in the inferior vena cava (IVC) and hepatic blood flow. Five numerical models of mechanical cavopulmonary assistance were investigated using a three-dimensional, reconstructed, patient-specific Fontan circulation from magnetic resonance imaging data.