BScMed (Hons I) MB BS (Hons II) FRACP PhD

Assoc. Professor David McKenzie is senior staff specialist and head of the Department of Respiratory and Sleep Medicine at the Prince of Wales Hospital.  In addition to carrying a full clinical, teaching and administrative load he has developed an international reputation for his basic and clinical research and has made a major contribution nationally to changing models of care and improving clinical practice, particularly in the management of COPD.

David has inpatient and out-patient responsibilities at The Prince of Wales Hospital and The Private of Wales Private Hospital. He is also responsible for pulmonary function and exercise testing laboratory and sleep investigation services. He has a busy private practice in Suite 20, and is well regarded for his expertise in occupational lung disorders.

 He has particular interests in respiratory failure in COPD and neurological disorders, brittle asthma, respiratory disorders in sleep and occupational lung disorders. 

 Assoc. Prof. McKenzie has extensive experience in occupational lung disorders and lectures on dust diseases and occupational asthma to medical students and occupational physicians. He has prepared numerous medicolegal reports relating to asbestos, silica, carcinoma, asthma, multiple chemical sensitivity, quadriplegia and other claims and appeared as an expert witness on many occasions. He has also prepared environmental impact reports and provided expert evidence relating to health effects from quarrying, mining, air pollution and silicon smelting.

 Administrative Responsibilities

As Convenor of the Thoracic Society of Australia and New Zealand’s Chronic Airflow Limitation Special Interest Group (1997-2002) and Chairman of the Australian and New Zealand COPD Guidelines Committee (2000-2004) he played a leading role in the development of the COPD guidelines. He was the principal author of a peer-reviewed publication of the COPDX guidelines. As a member of the Australian Lung Foundation COPD Executive and Co-ordinating Committees (1996-2007) he supervised the implementation of the COPD guidelines. Several tools were developed for general practitioners including a handbook, summary booklet, a diagnostic algorithm and a COPD action plan. In 2003 he received a medal from the Thoracic Society of Australia in recognition of his contributions to raising awareness of COPD and leadership in the guideline process.  

At a State level he has driven change in clinical practice through his supervision of the Respiratory project of the NSW Health Chronic and Complex Care Program from 2000–2005 and through chairmanship of the NSW Health Respiratory Clinical Expert Reference Group.  Assoc. Prof. McKenzie was instrumental in the formation of the Respiratory Network of the NSW Health Agency of Clinical Innovation (formerly GMCT), which now serves as the peak advisory body to the Minister and Director-General, and is co-chair of the Steering Committee (2005–date). The Steering Committee oversees 6 working groups and a Rural Taskforce with the network now comprising over two hundred multidisciplinary clinicians. 

Research Activities

Assoc. Prof. McKenzie has developed an international reputation for research into respiratory muscle function and control in healthy subjects and in patients with various respiratory or neuromuscular diseases or sleep apnoea.  He has developed novel methods for measurement of the neuromotor drive and its mechanical effectiveness, including the use of phrenic nerve stimulation to activate the diaphragm, cine-radiology and ultrasound to measure diaphragm length and shortening and single motor unit recordings of the diaphragm and other respiratory muscles. These methods have been used to advance knowledge of the impairment of respiratory muscle function in pateints with chronic obstructive pulmonary disease. A series of novel studies of respiratory muscle endurance documented for the first time that the diaphragm is highly resistant to fatigue in both healthy subjects and patients with COPD.

Assoc. Prof. McKenzie has also published work on a variety of clinical topics including evaluation of asthma education, pulmonary rehabilitation and management of tuberculosis and occupational lung disease. He published the first randomised controlled trial (RCT) demonstrating the effectiveness of asthma education in Australia. More recently Assoc. Prof. McKenzie supervised the first RCT to demonstrate effectiveness of cognitive behavioural therapy in preventing panic attacks in patients with COPD. With R McNamara he conducted the first RCT to show that water based exercise is more effective than standard pulmonary rehabilitation in patients with COPD and physical comorbidities. He has also been a chief investigator or co-investigator in 21 clinical trials of various pharmaceutical agents, including new treatments for pneumonia, asthma and chronic air flow limitation.