Independent risk factors for hypoxemia after surgery for acute aortic dissection.

OBJECTIVES: To determine risk factors associated with postoperative hypoxemia after surgery for acute type A aortic dissection. METHODS: We retrospectively analyzed the clinical data of 192 patients with acute type A aortic dissection who underwent surgery in Qingdao Municipal Hospital, Medical College of Qingdao University, Qingdao, China between January 2007 and December 2013. Patients were divided into hypoxemia group (n=55) [arterial partial pressure of oxygen (PaO2)/fraction of inspired oxygen (FiO2) ≤ 200 mm Hg] and non-hypoxemia group (n=137) [PaO2/FiO2 > 200 mm Hg]. Perioperative clinical data were analyzed and compared between the 2 groups. RESULTS: The incidence of postoperative hypoxemia after surgery for acute aortic dissection was 28.6% (55/192). Perioperative death occurred in 13 patients (6.8%). Multivariate regression identified body mass index (BMI) > 25 kg/m2 (OR=21.929, p=0.000), deep hypothermic circulatory arrest (DHCA) (OR=11.551, p=0.000), preoperative PaO2/FiO2 ≤ 300 mm Hg (OR=7.830, p=0.000) and blood transfusion > 6U in 24 hours postoperatively (OR=12.037, p=0.000) as independent predictors of postoperative hypoxemia for patients undergoing Stanford A aortic dissection surgery. CONCLUSION: Our study demonstrated that BMI > 25 kg/m2, DHCA, preoperative PaO2/FiO2 ≤ 300 mm Hg, and blood transfusion in 24 hours postoperatively > 6U were independent risk factors of the hypoxemia after acute type A aortic dissection aneurysm surgery.

Independent risk factors for ventilator-associated pneumonia after cardiac surgery.

OBJECTIVE: To investigate the related factors and pathogens of ventilator-associated pneumonia (VAP) after heart surgery so as to provide evidences for clinical prevention and therapy. METHODS: In total 1,688 cases were collected from January 2004 to January 2011. Overall 105 patients developed VAP. Retrospectively analyzed these patients after heart surgery to determine the clinical data, pathogens and treatment measures. RESULTS: The frequency of ventilator-associated pneumonia was 6.2% (105/1 688), and mortality was 25.7% (27/105), 198 pathogen strains were isolated by bacterial culture, in which Gram negative bacteria accounted for 69.2% (137/198), Gram positive bacteria 27.8% (55/198), and fungi 3.0% (6/198). The independent risk factors for VAP after cardiac surgery were: age >70 (p < .01), emergent surgery (p < .01), perioperative blood transfusions (p < 0.01), reintubation (p < .01) and days of mechanical ventilation (MV) (p < .01). Median length of stay in the ICU for patients who developed VAP or not was, respectively, (24.7 ± 4.5) days versus (3.2 ± 1.5) days (p < .05), and mortality was, respectively, 25.7% versus 2.9% in both populations (p < .05). CONCLUSION: Age >70, emergent surgery, perioperative blood transfusions, reintubation and days of MV are the risk factors for VAP in patients following cardiac surgery. P. aeruginosa, P. klebsiella, S. aureus, and Acinetobacter baumannii were the main pathogens of VAP. According to the cause of VAP, active prevention and treatment measures should be developed and applied to shorten the time of MV and improve chances of survival.

[Clinical analysis of 105 cases of ventilator-associated pneumonia after heart surgery].

OBJECTIVE: To investigate the related factors and pathogens of ventilator-associated pneumonia (VAP) after heart surgery. METHODS: VAP was diagnosed in 105 patients out of 1688 cases (6.2%) who underwent heart surgery in our department between January 2004 and January 2011. Clinical data, pathogens and treatments were analyzed. RESULTS: Incidence of VAP was 6.2% (105/1688), and 53.0% (105/198) in patients who required more than 48 hours of mechanical ventilation. One hundred and ninety-eight pathogen strains were isolated by bacterial culture, in which Gram negative bacteria accounted for 69.2% (137/198), Gram positive bacteria 27.8% (55/198), and fungi for 3.0% (6/198). Pseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumannii, Escherichia coli, and Staphylococcus aureus were the main pathogens of VAP. The independent risk factors for VAP were: age > 70 years, emergent surgery, perioperative transfusions, reintubation and days of mechanical ventilation (all P < 0.01). Median length of stay in the ICU for patients who developed VAP or not was (24.7 ± 4.5) days versus (3.2 ± 1.5) days, respectively (P < 0.05) and in-hospital mortality was 25.7% (27/105) versus 2.9% (46/1583) respectively (P < 0.05). CONCLUSIONS: Patients undergoing heart surgery have a high frequency of developing VAP, especially in patients that require more than 48 hours of mechanical ventilation. VAP is associated with high in-hospital mortality. Age > 70 years, emergent surgery, perioperative transfusions, reintubation and prolonged mechanical ventilation use are independent risk factors for VAP in patients following cardiac surgery. Pseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumannii, Escherichia coli, and Staphylococcus aureus are the main pathogens of VAP.