Identifying risk factors for postoperative pulmonary complications

AORN Journal, Oct, 2006 by Priscilla K. Gazarian

In health care today, the ability to predict and prevent adverse events such as postoperative pulmonary complications has become increasingly important as a measure of the safety and quality of care delivered. The need to improve quality of care within the constraints of current health care system economics, workforce shortages, and increasing patient care complexity means nurses must take a proactive approach to identifying and reducing risks of patient complications.

Traditionally, nurses have been instrumental in preventing adverse events. Preventable adverse events that have been linked to nursing care include falls, pressure ulcers, deep vein thromboses, urinary tract infections, and pneumonia. (1) The prevention of postoperative pulmonary complications needs further investigation, and nurses are well positioned to have an effect on reducing their incidence.

INCIDENCE

Postoperative pulmonary complications remain all too common after surgery. The rate of postoperative pulmonary complications for North Americans is estimated to be as high as one million of every 45 million people who undergo nonthoracic surgery. (2) The Agency for Healthcare Research and Quality (AHRQ) estimates that four patients of every 1,000 who undergo surgery will experience postoperative respiratory failure, and eight of every 1,000 will experience a pulmonary embolus. (3) This is more than the incidence of other postoperative complications measured by the AHRQ (eg, hemorrhage or hematoma, hip fracture, physiologic and metabolic derangement, wound dehiscence). (3) The only postoperative complication that occurs more frequently is sepsis. (3) Respiratory complications are the second most common reason for unexpected death or transfer to an intensive care unit and often are preventable. (4)

POSTOPERATIVE PULMONARY COMPLICATIONS

Less is known about postoperative pulmonary complication risk prediction or prevention than about cardiac complications or their prediction, even though postoperative pulmonary complications occur more frequently. (2,5) Although research related to postoperative pulmonary complication risk prediction exists, the state of the science in this area is still developing.

The most commonly studied postoperative pulmonary complication is pneumonia, however other complications that have been studied include atelectasis, (1-4,6-19) respiratory failure, (2,6) prolonged mechanical ventilation, (7,14) pneumothorax, (2) acute respiratory distress syndrome (ARDS), (15) pleural effusion, (2) and pulmonary embolus. (16) Pulmonary complications such as ARDS or respiratory failure are associated with higher morbidity and mortality and longer lengths of hospital stay and consume a significant amount of health care resources; (6,15) however, they are less frequently studied as outcomes. Although several risk prediction studies have been completed, the lack of consistency of outcome indicators makes it difficult to compare previous research results.

LITERATURE REVIEW METHODS

This review examines the existing evidence related to risk factors for the development of postoperative pulmonary complications among hospitalized adults. Common postoperative pulmonary complications used for search terms in this literature review included atelectasis, ARDS, pulmonary embolism, pulmonary edema, pneumonia, and respiratory distress syndrome. (16) Key search terms included postoperative complications, risk factors, and postoperative pulmonary complications including atelectasis, pneumonia, pulmonary edema, pulmonary embolism, respiratory distress syndrome, and ARDS. Studies were identified by searching electronic versions of the Cumulative Index of Nursing and Allied Health Literature (ie, CINAHL) and the Medical Literature Analysis and Retrieval System (ie, MEDLINE).

Articles included were original research that addressed pulmonary complications in postoperative adult patients and that were published in a peer-reviewed journal. No publication time limit was imposed. Studies that addressed thoracic or cardiac procedures such as pneumonectomy, thoracotomy, or open heart surgery (ie, involving direct disruption of the airway, chest wall, or lung tissue) were excluded.

LITERATURE SEARCH RESULTS

Forty-one abstracts were reviewed. Articles were eliminated if they did not examine a relationship between risk factors and postoperative pulmonary complications, if they were not primary research, or if they tested an intervention. In addition, the reference lists of the selected articles were manually searched to retrieve studies not recovered in the electronic search. Thirteen articles met the inclusion criteria. (2,5-15,17) These studies were conducted between 1991 and 2005.

The high morbidity and mortality associated with a postoperative pulmonary complication was cited as the major reason for studying the problem. The purposes of the studies were generally to identify risk factors; (2,5,7,13-15,17) identify relationships between risk factors and development of postoperative pulmonary complications; (6,9,12) and, in some cases, to determine if those risk factors could predict the occurrence of postoperative pulmonary complications. (5,10) Two studies were undertaken for the purpose of validating a risk prediction model. (5,8)