Perioperative Pulmonary Functions In Chronic Obstructive Pulmonary Disease (Copd )

Pulmonary function testing provides valuable information on the components of gas exchange in health and disease. The measurements of lung function can aid in the diagnosis of disease and in the assessment of the need for and effectiveness of respiratory therapeutics.Chronic obstructive pulmonary disease is typically considered an important risk factor for postoperative complications. Many authors reported that chronic obstructive pulmonary disease patients are at higher risk of postoperative complications.Anaesthesia for patients with COPD is associated with a number of problems and hazards. These include reduced sensitivity to carbon dioxide, hyperinflation with impaired function of the flattened diaphragm which may be further compromised in the immediate postoperative period due to the residual effects of neuromuscular blocking drugs. The problem of excessive mucous production is exacerbated by general anaesthesia, in addition to hyperresponsive airway in COPD patients.The present work was designed to study peri operative pulmonary functions in surgical patients with COPD undergoing lower abdominal or lower extremity operations under general versus regional anaesthesia. Special consideration was given to early postoperative period.This study included 120 patients, 90 of them were COPD patients and 30 of them formed the control group.The patients were divided into three equal main groups according to the anaesthetic technique:Group I: 40 patients (30 COPD, 10 control) received spinal analgesia. Group II: 40 patients (30 COPD, 10 control) received general anaesthesia with endotracheal intubation.Group III: 40 patients (30 COPD, 10 control) received general anaesthesia with laryngeal mask insertion.Every patient was subjected to complete history taking, physical examination, chest X-ray, ECG and complete blood investigations. Pulmonary functions were done pre and post operatively. Arterial blood gas was done pre, intra and postoperatively.The results showed that anaesthesia and surgery change the pulmonary functions especially in COPD patients. Changes with the use of spinal analgesia were less than with the use of general anaesthesia. Changes in pulmonary functions with general anaesthesia by LMA were less than changes that occur with general anaesthesia by endotracheal tube.Conclusion:The present study concludes that, the spinal anaesthesia is preferred to general anaesthesia and that general anaesthesia with laryngeal mask is preferable to general anaesthesia with endotracheal intubation.The study recommends the use of spinal anaesthesia in patients with COPD in lower abdominal operations or general anaesthesia with laryngeal mask aIrway. COPD patients with severe pulmonary dysfunction must be given O2 mask with appropriate Fi02 in early postoperative period in recovery room until full recovery to avoid postoperative hypoxaemia. Between parameters which evaluate the oxygenation status, aJ A appeared to be less sensitive and Qs/Qr (calculated) appeared to underestimate the degree of intrapulmonary shunt