14 Sep 10
By T Edrich, N Sadovnikoff
Curr Opin Anaesth. 2010;2:18-24
Patients with chronic obstructive lung disease experience an increased risk of perioperative pulmonary complications. This review presents an evidence-based approach to perioperative care designed to optimize management.
Recent findings: Recent research has provided guidance regarding intraoperative and postoperative administration of oxygen and the selective use of volatile agents. The significance of preoperative malnutrition and postoperative epidural analgesia on outcomes has also been explored further. The opportunity for anesthesiologists to engage in tobacco interventions and the benefits of addressing smoking cessation have been studied.
Optimization for surgery includes preoperative treatment of reversible airway obstruction and respiratory infections, smoking cessation, and possibly nutritional interventions. Meticulous intraoperative monitoring combined with a sound understanding of pathophysiological mechanisms underlying air trapping will help clinicians strike a balance between permissive hypercapnia and adequate ventilation.
08 Nov 09
By M Wildman, C Sanderson, J Groves, B Reeves, J Ayres, D Harrison, D Young and K Rowan
QJM 2009 102(6):389-399 http://qjmed.oxfordjournals.org/cgi/content/full/102/6/389
Decisions about the intensity of treatment for patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are influenced by predictions about survival and quality of life. Evidence suggests that these predictions are poorly calibrated and tend to be pessimistic.
The aim of this study was to develop an outcome prediction model for COPD patients to support treatment decisions.
A prospective multi-centre cohort study in Intensive Care Units (ICU) and Respiratory High Dependency Units (RHDU) in the UK recruited patients aged 45 years and older admitted with an exacerbation of obstructive lung disease. Data were collected on patientsí characteristics prior to ICU admission, and on their survival and quality of life after 180 days. An outcome prediction model was developed using multivariate logistic regression and bootstrapping.
Ninety-two ICUs (53% of those in the UK) and three RHDUs took part. A total of 832 patients were recruited. Cumulative 180-day mortality was 37.9%. Using data available at the time of admission to the units, a prognostic model was developed which had an estimated area under the receiver operating characteristic curve (ëcí) of 74.7% after bootstrapping that was more discriminating than the clinicians (P = 0.033) and was well calibrated.
This study has produced an outcome prediction model with slightly better discrimination and much better calibration than the participating clinicians. It has the potential to support risk adjustment and clinical decision making about admission to intensive care.
12 Aug 09
By M Cosio, M Saetta and A Agusti
Chronic obstructive pulmonary disease (COPD) is a major cause of illness and death throughout the world. It affects about 10% of the general population, but its prevalence among heavy smokers can reach 50%. COPD is the fourth leading cause of death in most industrialized countries, and it is projected to be the third leading cause of death worldwide by 2020. Tobacco smoking is the primary risk factor for the development of COPD, but other factors, such as burning biomass fuels for cooking and heating, are important causes of COPD in many developing countries.
A principal feature of COPD is a limitation of airflow that is not fully reversible and is associated with an abnormal inflammatory response in the small airways and alveoli. The principal abnormalities in small airways are the presence of an inflammatory cellular infiltrate and a remodeling that thickens the airway wall, thereby reducing the airway diameter and increasing resistance to flow. Additional features are prominent inflammatory infiltrates in the alveolar walls, destruction of alveoli, and enlargement of air spaces. These anatomical hallmarks of emphysema reduce the elastic pressure that generates expiratory flow. Chronic bronchitis, a condition that according to some authors has little to do with the development of airflow obstruction, develops in approximately 50% of smokers.