An observational study to know the association of leukocytosis and fever with infection in post cardiac surgery patients.
BACKGROUND
Leukocytosis and fever in the absence of infection are common phenomena in post surgical period. The systemic inflammatory response syndrome induced by surgical trauma is a well-known entity, with resultant release of variety of inflammatory cytokines leading to fever and/or leukocytosis in spite of the absence of infection.


OBJECTIVE
To know the association of leukocytosis and fever with infection in immediate post cardiac surgical period.


METHODS
It was a retrospective, observational study including 569 patients, who underwent cardiac surgeries in our institute. All demographic data, comorbidities and other factors associated with fever and/or leukocytosis were analyzed. The sensitivity and specificity of fever and/or leukocytosis were analyzed for the diagnosis of infection.


RESULTS
Out of 569 patients; 49 patients (9%) had evidence of infection on microbiological culture. Mean total leukocyte counts (TLC) on zero and 1st postoperative days were associated with infection with a sensitivity (75.5% and 63.3%) and specificity (15.8% and 24.0%) respectively. Mean maximum temperature (Tmax) on zero and 1st postoperative days were associated with infection with a sensitivity (20.4% and 24.5%) and specificity of (82.5% and 83.3%) respectively. The combined sensitivity and specificity of leukocytosis and fever for the diagnosis of infection on 2nd postoperative day was 14.3% and 91.5% respectively.


CONCLUSIONS
Fever and leukocytosis are poor predictors of diagnosing infection on the first two postoperative days. However, fever and leukocytosis combined together have low sensitivity (14.3%) with high specificity (91.5%) for the diagnosis of infection on the 2nd and subsequent postoperative days.
Kumar
Satish
S
Department of Anesthesiology, Critical Care and Cardiovascular Surgery, Escorts Heart Institute and Research Centre, New Delhi, India.
Mehta
Yatin
Y
Vats
Mayank
M
Chand
Rajesh
R
Kapoor
Pawan
P
Trehan
Naresh
N
D006348:Cardiac Surgical Procedures; D005260:Female; D005334:Fever / Q000175:diagnosis*; D006801:Humans; D007239:Infections / Q000175:diagnosis*; D007964:Leukocytosis / Q000175:diagnosis*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity