Risk score elaboration for mediastinitis after coronary artery bypass grafting.
BACKGROUND
The mediastinitis is a serious postoperative complication of cardiac surgery, with an incidence of 0.4 to 5% and mortality between 14 and 47%. Several models were proposed to assess risk of mediastinitis after cardiac surgery. However, most of these models do not evaluate the postoperative morbidity.


OBJECTIVE
This study aims to develop a score risk model to predict the risk of mediastinitis for patients undergoing coronary artery bypass grafting.


METHODS
The study sample included data from 2,809 adult patients undergoing coronary artery bypass grafting between January 1996 and December 2007 at Hospital São Lucas -PUCRS. Logistic regression was used to examine the relationship between risk factors and the development of mediastinitis. Data from 1,889 patients were used to develop the model and its performance was evaluated in the remaining data (n=920). The definitive model was created with the data analysis of 2,809 patients.


RESULTS
The rate of mediastinitis was 3.3%, with mortality of 26.6%. In the multivariate analysis, five variables remained independent predictors of the outcome: chronic obstructive pulmonary disease, obesity, surgical reintervention, blood transfusion and stable angina class IV or unstable. The area under the ROC curve was 0.72 (95% CI, 0.67-0.78) and P = 0.61.


CONCLUSIONS
The risk score was constructed for use in daily practice to calculate the rate of mediastinitis after coronary artery bypass grafting. The score includes routinely collected variables and is simple to use.
Magedanz
Ellen Hettwer
EH
Postoperative Cardiac Surgery Unit, PUCRS Sao Lucas Hospital, Porto Alegre, Rio Grande do Sul, Brazil. ellenmagedanz@yahoo.com.br
Bodanese
Luiz Carlos
LC
Guaragna
João Carlos Vieira da Costa
JC
Albuquerque
Luciano Cabral
LC
Martins
Valério
V
Minossi
Silvia Daniela
SD
Piccoli
Jacqueline da Costa Escobar
Jda C
Goldani
Marco Antônio
MA
D001026:Coronary Artery Bypass / Q000009:adverse effects*; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008297:Male; D008480:Mediastinitis / Q000209:etiology* / Q000401:mortality / Q000517:prevention & control; D008875:Middle Aged; D018570:Risk Assessment / Q000379:methods