Littlejohn, A.Bowles, FelicityBigalke, R.D.Cameron, Colin McKenzieGilchrist, Frances M.C.Jordaan, E.Morren, A.J.Verster, Anna J.M.Verwoerd, Daniel WynandWalker, Jane B.Steyn, P.J.J.2015-12-072015-12-0720151982Littlejohn, A & Bowles, F 1982, 'Studies on the physiopathology of chronic obstructive pulmonary disease in the horse. VI. The alveolar dead space’, Onderstepoort Journal of Veterinary Research, vol. 49, no. 2, pp. 71-72.0330-2465http://hdl.handle.net/2263/51087The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.The alveolar dead space (VDalv) as a percentage of tidal volume was calculated in horses by substituting the values for partial pressure of carbon dioxide in end-expiratory gas (PE’CO₂) and for partial pressure of carbon dioxide in arterial blood (PaC0₂) in the equation: % VDalv =( (PaC0₂ - PE'C0₂)/PaC0₂) X 100. The mean % VDalv of 12 chronic obstructive pulmonary disease (COPD) subjects was 3 times greater than that of 22 normal subjects. Since the larger % VDalv of COPD subjects was due to an elevated PaC0₂, it was considered that maldistribution of ventilation was the principal cause of their increased % VDalv compared with that of clinically normal subjects.en©ARC - Onderstepoort and Faculty of Veterinary Science, University of Pretoria (original). ©University of Pretoria. Dept. of Library Services (digital).Veterinary medicineVeterinary medicine -- South AfricaArticle