Abstracts from papers

S FROM PAPERS RESPIRATORY PHYSIOLOGY: Scientific Editors P. HUGH-JONES AND E. J. M. CAMPBELL, Brit. Med. Bulletin, Vol. 19, No. I, Jan. 1963, pp. 1-96. 30s. There is a high morbidity and mortality among acute paraplegic patients from chest complications. The cervical patients frequently suffer pulmonary emboli and develop pneumonia. Thoracic paraplegics may have additional fractures to their ribs causing haemopneumothoraces. Because of these complications the physician who looks after these patients must have an adequate understanding of the treatment of chest disorders, and this entails a knowledge of pulmonary physiology. The January edition of the British Medical Bulletin is devoted to current trends in Respiratory Physiology. The panel of contributors is composed of a distinguished team of physiologists and physicians. They discuss such topics as the clinical and neurological regulations of breathing and the distribution of gas and the blood flow within the lungs. J. G. Widdicombe's article is of particular interest. He reviews the significance of reflexes arising within the lungs, and their influence upon respiration and circulation. He points out the importance of irritant reflexes that cause the integrated act of coughing, and of pulmonary vascular reflexes whereby sudden increases of pressure within the lungs, caused by pulmonary congestion or emboli, may cause profound changes in the cardio­ vascular system. The Hering-Breuer inflation and deflation reflexes, first described in animals 1868, are discussed and it is suggested that they are weak in man. In another article on breathlessness E. J. M. Campbell and J. B. L. Howell describe a series of results obtained after respiratory loading of normal and anaesthetised subjects, that suggest that there are other more important reflexes which regulate breathing whose receptors are situated in the spindles of the muscles of respiration. They elaborate a new concept of length-tension inappropriateness within these receptors to explain the sensation of dys­ pnoea. C. G. Caro discusses a complex subject in an article on the physics of blood flow through the lungs. He points out that the blood does not perfuse the lung in a steady continuous stream, but fluctuates greatly. He attempts to analyse this flow by resolving it into two components, the mean flow and the oscillatory flow. The mean flow is influ­ enced by such factors as the physical properties of the blood and blood vessels, and the pressures developed within the chambers of the heart and within the lung substance and alveoli. The oscillatory flow depends upon the varying pressures imparted to the blood by the beating of the heart. These pressures are modified by the pulmonary blood vessels. Drs. Duke and De Lee describe some of the physiological and pathological mechanisms whereby the blood flow of the lungs is modified, and the significance of the interrelation­ ship of the pulmonary and systemic circulations. The whole symposium is written in a stimulating and provocative manner posing as many questions as it answers, but stressing for the physician concerned with the care of paraplegic patients that 'ours is surely an age of integration in Science where ideas and methods developed in one discipline are being applied to another'. DISORDERS OF TEMPERATURE REGULATION IN ACUTE TRAUMATIC TETRAPLEGIA: H. G. PLEDGER (1962), J. Bone Jt Surg., 44, 110. Following a short survey of the literature on the subject of thermoregulation in tetraplegia in man as well as animals, the author described a patient with a tetraplegia following fracture of the 5th and 6th cervical vertebrae, who developed hypothermia shortly after being rendered tetraplegic. In addition to a complete motor and sensory loss below C6, there was a bilateral Horner's syndrome with nasal congestion (Guttmann's sign) and anhidrosis. The rectal temperature sank to 30·8°C. (8T4°F.), the electrocardiogram showed bradycardia (40 per minute), delayed conduction and J waves-all characteristic