RESPIRATORY PHYSIOLOGY – Part 2 ANAESTHESIA TUTORIAL OF THE WEEK 160

Before continuing, try to answer the following questions. The answers can be found at the end of the article, together with an explanation. 1. The oxyhaemoglobin dissociation curve is shifted to the left by: a) an increase in arterial PCO2 b) acidosis c) a decrease in 2,3 DPG d) carbon monoxide e) a fall in temperature 2. Anatomy of the respiratory tract a) the alveoli humidify gas b) generations 1- 18 are known as the conducting zone of the lungs c) there are 25 bronchial generations d) bifurication of the bronchi occurs at T4 e) the lungs are lined with transistional epithelium 3. Dead space a) is defined as the volume of gas which does take part in gas exchange b) physiological dead space is the same as alveolar dead space c) anatomical dead space is measured by the Bohr equation d) dead space is usually about 45 % of tidal volume e) occurs with pneumonia 4. Pulmonary vascular resistance a) is high at high lung volumes b) is low at low lung volumes c) can cause heart failure d) is calculated using PCWP e) is decreased by nitrous oxide 5. Diffusion of gases a) is increased with a decrease in surface area b) is indirectly proportional to the concentration gradient c) is not governed by Grahams law d) is directly proportional to the thickness e) is decreased according to Beers la