Prophylactic Penehyclidine Hydrochloride Inhalation and 3-year Outcome After Surgery

Postoperative pulmonary complications (PPCs) are major causes of postoperative morbidity, mortality, and prolonged hospital stay. The incidence of PPCs was found to vary from 2 to 19%, but this rate may be as high as 41 to 75% in patients after intrathoracic and intraabdominal surgery. According to Canet's model, the predicted incidence of PPCs in high-risk patients (ARISCAT risk index ≥45 points) is 42.1%. Use of effective strategies to prevent PPCs is essential for those high-risk patients. As a bronchodilator, anticholinergic inhalation may be helpful. Studies showed that, in high-risk patients undergoing intrathoracic surgery, airway resistance is increased due to bronchial hyperresponsiveness, which increased the risk of PPCs. Inhalation of anticholinergic bronchodilator can reduce the activity of vagus nerve and relieve high airway resistance, which may decrease the risk of bronchospasm and other PPCs. It has been shown that M1, M3-receptor selective blockers have better effects than β2-receptor activator in dilating bronchia. Penehyclidine hydrochloride is a new anticholinergic agent, which selectively blocks M1 and M3 receptors. Preclinical studies found that it also has anti-inflammation effects. In a pilot study of the investigators, prophylactic inhalation of penehyclidine decreased the incidence of bronchospasm and the use of aminophylline in elderly patients after long-duration surgery. In a previous randomized controlled trial, 864 high-risk patients were recruited and randomized to receive prophylactic inhalation of either penehyclidine or placebo. The investigators hypothesize that prophylactically penehyclidine hydrochloride inhalation may improve long-term outcomes in this patient population by reducing PPCs. The purpose of this 3-year follow-up study is to investigate whether prophylactically penehyclidine hydrochloride inhalation can affect the 3-year outcomes in high-risk patients recruited in the previous randomized controlled trial.