EFFECT OF DIFERENT MODES OF VENTILATION ON SOME HEAMODYNAMIC FUNCTIONS

Abstract

The mouth is made up of the vestibule and the mouth cavity, the former communicating with the latter through the aperture of the mouth. The vestibule is formed by the lips and cheeks without and by the gums and teeth within. An important feature is the opening of the parotid duct on a small papilla opposite the 2nd upper molar tooth Nonnally the walls of the vestibule are kept together by the tone of the facial muscles; a characteristic feature of a facial nerve paralysis is that the cheek falls away from the teeth and gums, enabling food and drink to collect in, and dribble out of, the now patulous vestibule. The function or respiration is to ensure the needs of the tissues for oxygen and for removal of CO,. The Process of respiration can be divided into four major mechanistic events: Pulmonary ventilation: Which means the inflow and outflow of air between the atmosphere and lung alveoli. Diffusion: Diffusion of oxygen and carbon dioxide between the alveoli and the blood. Pulmonary perfusion: The volume of blood Pumped by the right ventricle to the lungs is 5L/min. Gas transport function of the blood: The transport of oxygen and carbon dioxide by blood is mainly in chemical combination. The Process of pulmonary ventilation is regulated by respiratory centers present in the brain stem according to cellular needs. (Zwart, et al. 1984). Compliance refers to the ease with which the lungs and thoracic wall can be expanded. High compliance means that the lungs and thoracic wall expanded easily. Low compliance means that they resist expansion. Compliance is related to two principal factors: elasticity and surface tension. Presence of elastic fibers in lung tissue results in high compliance. If surface tension within lung tissue were high, the tissues would resist expansion, but surfactant lowers surface tension and thus