Common Inflammatory Markers After Cardiac Surgery in Infants and Their Relation to Blood Stream Sepsis

Limited information exists on trends of common inflammatory markers after infant heart surgery and their role in identifying post-operative sepsis.

275 consecutive infants undergoing cardiac surgery (231 with and 44 without Cardiopulmonary Bypass) were studied prospectively. Daily trends (0–4 day post-operative) of leucocyte counts, platelet counts and C-reactive protein were recorded. Association of these trends with early post-operative bloodstream sepsis, Cardiopulmonary Bypass and surgical outcomes were studied.

Trends of these inflammatory markers were noted. While off-Cardiopulmonary Bypass Surgery, and sepsis were associated with a statisticaly insignificant rise in total leucocyte count peaking on first post-operative day, Cardiopulmonary Bypass exposure was associated with significant decline (p = 0.002), more pronounced with Cardiopulmonary Bypass-exposure exceeding 150 min. Percentage of neutrophils showed a rise (maximum on first post-operative day) but no significant association with sepsis or Cardiopulmonary Bypass.

Platelet counts significantly declined after surgery, with nadir on 2^nd POD (p < 0.001), the drop being more marked in patients operated on Cardiopulmonary Bypass (p < 0.005). Counts were significantly lower in patients exposed to >150 min Cardiopulmonary Bypass compared to those with shorter Cardiopulmonary Bypass. Septic patients had significantly lower platelet counts than uninfected patients, decline >2 SD from mean pre-operative level strongly associated with sepsis (p < 0.001).

C-Reactive Protein levels rose markedly after surgery, peaking on 2^nd POD; levels were significantly higher if operated on Cardiopulmonary Bypass. Cardiopulmonary Bypass >150 min was associated with lower mean C-Reactive Protein on first post-operative day, but significantly higher values on third and fourth post-operative days, as compared to Cardiopulmonary Bypass <150 min. Comparison of infected versus non-infected patients showed significantly higher mean C-Reactive Protein in the former group.

While leucocyte count, platelet count and C-Reactive Protein emerged as useful markers of post-operative inflammatory response and reaction to Cardiopulmonary Bypass, they proved unsatisfactory predictors of early post-operative sepsis.