Risk Factors of Sternal Wound Infection After Coronary Artery Bypass Graft

Study Overview
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Brief Summary
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The investigators are trying to evaluate the performance of neutrophil and lymphocyte counts as a risk factor of deep sternal wound infection after coronary artery bypass graft surgery.

Detailed Description
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Deep sternal wound infection after coronary artery bypass graft is a very dangerous complication as it prolongs hospital stay, increase morbidity and mortality, and increase cost of care. As a risk factor of surgical site infection, risk index reported by NNIS (national nosocomial infection surveillance), Euroscore, or Society of thoracic surgeon risk score are currently used. However, as various performances are reported regarding these index or scoring systems, and many factors are needed for these index or scoring system, there is a need to develop a more simple risk factor with better performance. We focused on the differential blood cell count, as the neutrophil and lymphocyte count are related to the degree of surgical invasion, and inflammatory response. Previous studies reported that the neutrophilia or lymphopenia is related to postoperative infection. Therefore, we are trying to evaluate the performance of preoperative or postoperative the blood cell differential count as a risk factor for sternal wound infection after coronary artery bypass surgery.

Official Title
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Risk Factors of Sternal Wound Infection After Coronary Artery Bypass Graft

Conditions
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Coronary Artery Bypass Graft, Median Sternotomy

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Those underwent coronary artery bypass graft surgery with median sternotomy in Samsung Medical Center during the period of January 2008 and December 2011. Exclusion Criteria: Those underwent coronary artery bypass graft surgery with mini-thoracotomy Those with insufficient study data recognized by electronic medical record

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Coronary Artery Bypass Graft Group<br>Those underwent coronary artery bypass graft surgery with median sternotomy in Samsung Medical Center during the period of January 2008 and December 2011. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative surgical wound infection | postoperative surgical wound infection within first week after the end of coronary artery bypass graft surgery, classified as a superfical or deep sternal wound infection | within first week after the end of coronary artery bypass graft surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| preoperative total leukocyte count | preoperative total leukocyte count | 1 day before surgery | 
| preoperative neutrophil count | preoperative neutrophil count | 1 day before surgery | 
| preoperative lymphocyte count | preoperative lymphocyte count | 1 day before surgery | 
| postoperative total leukocyte count | postoprative total leukocyte count | 2 hour after the end of surgery | 
| postoperative neutrophil count | postoperative neutrophil count | 2 hour after the end of surgery | 
| postoperative lymphocyte count | postoperative lymphocyte count | 2 hour after the end of surgery | 
| preoperative NNIS risk index | preoperative NNIS risk index | 1 day before surgery | 
| preoperative EuroScore | preoperative EuroScore | 1 day before surgery | 
| Preoperative STS | Preoperative STS (Society of Thoracic Surgeons risk score) | 1 day before surgery | 
| the incidence of surgical reopen with surgical wound infection | the incidence of surgical reopen with surgical wound infection | within 1 month after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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risk factor, sternal wound infection, coronary artery bypass graft