الفهرس 
Overview of postoperative pulmonary complicationsOnly 14 pages are availabe for public view
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Abstract
Pulmonary complications are major causes of morbidity and mortality during the postoperative period. They include atelectasis, bronchospasm, pneumonia and exacerbation of chronic lung disease. However, the list can be expanded to include acute upper airway obstruction, complications from obstructive sleep apnea, pleural effusions, chemical pneumonitis, pulmonary edema, hypoxemia due to abdominal compartment syndrome and tracheal laceration.
Estimation of risk factors of Postoperative Pulmonary Complications (PPCs) is a necessary part of the preoperative evaluation. The risk factors may be grouped into patient-related, procedure-related and anesthesia-related. Procedure related factors are more important than patient related factors in predicting the risk of PPCs.
Usually, in surgical procedures with no cavity opening or airway manipulation, the risk for PPCs is low. The rate of complication is inversely related to the distance of the surgical incision from the diaphragm. Patients undergoing upper abdominal and thoracic surgery have a decreased postoperative vital capacity which leads to VA/Q mismatch and contributes to development of hypoxemia. Thus, the rate is substantially higher for thoracic and upper abdominal surgeries than for lower abdominal surgery.
A complete history and physical examination are the most important elements of preoperative risk assessment. Any history suggesting unrecognized chronic lung disease or heart failure, such as exercise intolerance, unexplained dyspnea or cough, requires further consideration. Physical examination should be directed toward evidence for obstructive lung disease especially noting decreased breath sounds, wheezes or prolonged expiratory phase.
The ultimate goal of preoperative evaluation and risk assessment for PPCs lies in the individualization of perioperative strategies able to reduce the calculated risk. Strategies to reduce postoperative pulmonary complications should generally be reserved for those at higher than average risk. As an example, patients undergoing upper abdominal or open thoracic surgery with at least one other risk factor are at high risk. Patients undergoing other types of surgical procedures are at lower risk; these individuals are candidates for risk reduction strategies if multiple other risk factors are present.
Risk reduction strategies include preoperative strategies such as smoking cessation, optimization of underlying chronic lung disease and patient education. Intraoperative strategies such as choice of type of anesthesia and neuromuscular blockade , lung protective ventilation . Postoperative strategies such as lung expansion maneuvers, pain control .
Postoperative interventions that are definitely beneficial for high risk patients include deep breathing exercises or incentive spirometry and use of epidural analgesia, where appropriate, in place of parenteral opioids. Continuous positive airway pressure (CPAP), intercostal nerve blocks, limiting use of nasogastric tubes (for symptoms only) after abdominal surgeries and early mobilization are probably beneficial postoperative interventions.