30 November 2009 Respiratory Physiology Lab this week: A case study and measuring lung volumes and capacities with Powerlab. Bring calculator and textbook to lab.

Respiration is the overall movement of gases between the outside environment and the internal cells. Ventilation is the movement of air in and out of the lungs. O2O2 O2O2 CO 2 Carbon Dioxide reacts with water! CO 2 + H 2 0 ↔ H 2 CO 3 ↔ H + + HCO 3 - Carbonic Acid Bicarbonate So disturbances in gas exchange or ventilation are often associated with disruptions of pH. pH changes with Hypoventilation & Hyperventilation

Respiratory Physiology The physics of air flow 1)Flow in tubes 2) Ventilation Poiseulle’s equation

Upper Respiratory Tract The Structure underlying the function: Lower Respiratory Tract Bronchitis= infection/inflammation of conducting airways Asthma = smooth muscles contract to increase resistance to airflow in conducting airways.

Pneumothorax (unilateral due to each lung having its own compartment. Greg R. and the story of spontaneous pneumothorax Visceral pleura and parietal pleura separated by fluid-filled pleural cavity which allows lung and chest wall to slide relative to each other but remain adhered unless air enters the pleural cavity (which leads to collapse of the lung and outward expansion of chest wall on that side.)

Upper Tract Sleep Apnea & CPAP

Continuous Positive Airway Pressure

Relaxation/contraction of circular smooth muscle lining these “airways’” determines how easily airflow can occur (bronchodilation vs. bronchoconstriction). Most gas exchange occurs in the ~8,000,000 alveolar sacs. Figure 13-2 Anatomical Dead Space

Bronchopulmonary segments and Surgical resection

Figure 22.5 Smoker’s hack

Respiratory Epithelium of Airway (Not alveolus!) Mucus escalator

What does a river delta and your lungs have in common?

Figure 13-2 Anatomical Dead Space Impaction Sedimentation Brownian Diffusion Particle Filtration: deposition varies Decrease In Flow Rate

Pulmonary arterial blood = low in O 2 Cartilage prevents collapse of airways during expiration.

Figure 22.10

Type I pneumocytes are simple squamous epithelia that comprise the majority of the surface area. Type II pneumocytes secrete surfactant. Gas exchange by diffusion based on gradients.

Figure Who cares? Respiratory Distress Syndrome of the Newborn

Table 13.04