Hannan et al identified risk factors for 30-day readmission following a coronary artery bypass graft (CABG) procedure. This can help to identify a patient who may benefit from more aggressive management. The authors are from the University of Albany, Maimonides and Columbia-Presbyterian Medical Centers in New York City, New York University Medical Center, Medical University of Toledo, Ohio State University, and Drexel University.


Patient selection: CABG


Outcome: 30-day hospital readmission


The leading cause for readmission was infection (surgical site, sepsis, pneumonia, other), which represented a quarter of the cases.


Risk factors independently associated with 30-day readmission:

(1) age > 70 years

(2) female gender

(3) race Afro-American

(4) body mass index (BMI) >= 35 kg per square meter)

(5) comorbidities (see below)

(6) post-operative renal failure

(7) unplanned cardiac reoperation

(8) primary payer Medicare or Medicaid

(9) discharge to a skilled nursing facility

(10) saphenous vein graft only (no use of internal mammary artery)

(11) longer length of stay (>= 5 days)



(1) cerebrovascular disease

(2) periphral vascular disease

(3) congestive heart failure

(4) chronic obstructive pulmonary disease (COPD)

(5) extensive aortic atherosclerosis

(6) diabetes mellitus

(7) 3-vessel coronary artery disease

(8) immunodeficiency

(9) left ventricular ejection fraction < 30%

(10) serum creatinine > 2.5 mg/dL

(11) dialysis


Of these risk factors the only ones with adjusted odds ratios > 1.5:

(1) body mass index >= 40 kg per square meter (OR 1.6)

(2) unplanned cardiac reoperation (OR 1.6)

(3) length of stay >= 7 days (OR 1.7 to 2.1)


Because of the relatively low odds ratios, multiple risk factors must be present before the cumulative odds become significant.


To read more or access our algorithms and calculators, please log in or register.