In patients with asthma, a history of smoking or severe asthma are risk factors for postoperative pulmonary complications (PPC), whereas in patients with chronic obstructive pulmonary disease (COPD), age, upper abdominal surgery, and long duration of surgery are risk factors for PPC, according to an article published in BMC Pulmonary Medicine.
Takanori Numata, MD, of the division of respiratory diseases, department of internal medicine, Jikei University School of Medicine, Tokyo, Japan, and colleagues evaluated 346 adult patients with pulmonary diseases who underwent nonpulmonary surgery (excluding cataract surgery) from April 2014 through March 2015 in Jikei University hospital. The investigators retrospectively evaluated physiological backgrounds, surgical factors, and perioperative specific treatment for asthma and COPD to identify risk factors for PPC.
A total of 29 patients with pulmonary diseases (22 with asthma and 7 with COPD) developed PPC. In patients with asthma, smoking index (≥20 pack-years), peripheral blood eosinophil count (≥200/mm3), and disease severity (Global Initiative for Asthma Step ≥3) were significantly associated with PPC in the multivariate logistic regression analysis, with odds ratios (OR) of 5.4, 0.31, and 3.2, respectively.
In patients with COPD, older age, introducing treatment for COPD, upper abdominal surgery, and operation duration (≥5 hours) were significantly associated with PPC, with ORs of 1.18, 0.09, 21.2, and 9.5, respectively.
The investigators noted that treating asthma with perioperative systemic corticosteroids seemed to significantly increase the risk for PPCs in the univariate analysis; however, this association was not detected in the multivariate logistic analysis.
The finding that peripheral blood eosinophilia and a history of heavy smoking are significantly associated with PPCs in patients with asthma is noteworthy considering that both variables are also implicated in steroid responsiveness. In addition, a peripheral blood eosinophil count ≥200/mm3 decreased the risk for PPCs to one-third, while a history of heavy smoking increased the risk 5-fold. In COPD, the introduction of treatment such as long-acting bronchodilators reduced the risk of PPC.
Study limitations included the retrospective case-control design, the use of data from a single institution, having fewer patients than expected, and the low incidence of PPC in this population.
Numata T, Nakayama K, Fuji S, et al. Risk factors of postoperative pulmonary complications in patients with asthma and COPD. BMC Pulmon Med. 2018:18:4. doi:10.1186/s12890-017-0570-8