'Lone' increase in C-reactive protein after cardiac surgery: prevalence, clinical characteristics, in-hospital course, and prognostic value

Whole Blood Reactivity to Viral and Bacterial Pathogens after Non-Emergent Cardiac Surgery during the Acute and Convalescence Periods Demonstrates a Distinctive Profile of Cytokines Production Compared to the Preoperative Baseline in Cohort of 108 Patients, Suggesting Immunological Reprogramming during the 28 Days Traditionally Recognized as the Post-Surgical Recovery Period

The release of danger signals from tissues in response to trauma during cardiac surgery creates conditions to reprogram the immune system to subsequent challenges posed by pathogens in the postoperative period. To demonstrate this, we tested immunoreactivity before surgery as the baseline (tbaseline), followed by subsequent challenges during the acute phase (t24h), convalescence (t7d), and long-term recovery (t3m). For 108 patients undergoing elective heart surgery, whole blood was stimulated with lipopolysaccharide (LPS), Influenza A virus subtype N2 (H3N2), or the Flublok™ vaccine to represent common pathogenic challenges. Leukocytosis, platelet count, and serum C-reactive protein (CRP) were used to measure non-specific inflammation. Cytokines were measured after 18 h of stimulation to reflect activation of the various cell types (activated neutrophils-IL-8; activated T cells-IL-2, IFNγ, activated monocyte (MO)-TNFα, IL-6, and deactivated or atypically activated MO and/or T cells-M-CSF, IL-10). IL-2 and IL-10 were increased at t7d, while TNFα was suppressed at t24h when LPS was utilized. Interestingly, M-CSF and IL-6 production was elevated at seven days in response to all stimuli compared to baseline. While some non-specific markers of inflammation (white cell count, IL-6, and IL-8) returned to presurgical levels at t3m, CRP and platelet counts remained elevated. We showed that surgical stimulus reprograms leukocyte response to LPS with only partial restoration of non-specific markers of inflammation.

Effects of dexamethasone on early cognitive decline after cardiac surgery: A randomised controlled trial

BACKGROUND

Postoperative cognitive decline (POCD), a very common complication after cardiac surgery, is characterised by impairment of both memory function and intellectual ability as well as being associated with increased use of healthcare resources. The investigators focused on the role of the inflammatory response to a surgical procedure as a potential factor involved in the pathogenesis of POCD.

OBJECTIVE

The use of prophylactic dexamethasone to attenuate the inflammatory response was hypothesised to reduce the risk of POCD.

DESIGN

Randomised controlled study.

SETTING

Single university teaching hospital, from March 2015 to January 2016.

PATIENTS

A total of 169 patients scheduled for elective cardiac surgery were enrolled, and 161 patients were included in the analyses.

INTERVENTION

Patients were randomised to receive a single intravenous bolus of 0.1 mg kg dexamethasone (n = 85) or placebo (n = 84) 10 h before the surgery.

MAIN OUTCOME MEASURES

The primary outcome measure in both groups was the incidence of POCD on the 6th day after surgery. The investigators also evaluated the effect of dexamethasone on the incidence of systemic inflammatory response syndrome, postoperative C-reactive protein levels and postoperative serum S100β protein levels.

RESULTS

Compared to the placebo group, the dexamethasone group showed statistically significant reductions in the incidence of POCD (relative risk, 0.43; 95% confidence interval, 0.21 to 0.89; P = 0.02), the incidence of systemic inflammatory response syndrome (30.0 versus 58.0%, P < 0.001) and postoperative C-reactive protein levels (P < 0.001). Postoperative S100β levels were insignificantly lower (P = 0.56) in the dexamethasone group.

CONCLUSION

Preoperative administration of dexamethasone reduced the inflammatory response and thereby decreased the risk of early POCD after cardiac surgery.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT02767713.

Acute systemic inflammatory response after cardiac surgery in patients infected with human immunodeficiency virus using clinical and inflammatory markers

BACKGROUND

Immediate post-cardiopulmonary bypass (CPB) immune responses and organ injuries in immune-compromised patients remain poorly documented.

METHOD

Sixty-one consecutive patients (30 HIV seropositive and 31 seronegative), undergoing elective cardiac valve(s) replacement were enrolled, from a single center hospital, after informed consent was obtained. C-reactive protein (CRP) and Erythrocyte sedimentation rate (ESR) were used as biomarkers of acute inflammatory response.

RESULTS

The mean age was similar between the HIV seropositive and negative group. Pre-operatively, CRP (p=0.388) and ESR (p=0.817) were comparable. The CPB events and durations were significantly different between the two groups: duration (p=0.021), clamp aortic duration (p=0.026), bloodtransfusion (p=0.013), total urine output (p=0.035) and peak lactate (p=0.040). Post-operatively, there was significant increased biomarkers level in both groups, albeit not between the groups with a significant negative correlation between the mean change in CRP levels and mechanical ventilation (r=0.548, p=0.002) in the seropositive group (r=0.025, p=0.893). The correlation between pre-operative and post-operative difference in CRP and ICU stay was not significant in both groups. A significant drop (p=<0.001) in CD4 cells was documented post-operatively in the HIV seropositive group.

CONCLUSION

HIV positive patients' post-operative reactions to cardiac surgery supported by CPB are similar to those of HIV seronegative patients.

Procalcitonin and white blood cells, combined predictors of infection in cardiac surgery patients

BACKGROUND

Sepsis is strongly associated with an increased risk of postoperative mortality, longer length of hospital stay, and elevated health care costs. Early clinical symptoms overlap with those of systemic inflammatory response syndrome, a response that commonly occurs after cardiac surgery with cardiopulmonary bypass. Since a combination of biomarkers has been demonstrated to improve the prediction of postoperative infection, the objective of the present study was to test whether the combination of C-reactive protein (CRP), white blood cells (WBC), and procalcitonin (PCT) is able to predict postoperative infection in a large cohort of cardiac surgery patients.

MATERIAL AND METHODS

Case-control study involving 423 patients who underwent cardiac surgery with cardiopulmonary bypass. Patients were retrospectively classified into two groups based on whether they developed severe sepsis or septic shock during the postoperative period. Blood samples for biological measurements (PCT, CRP, and WBC) were drawn on the first day in the intensive care unit, then once daily in the morning until the 10th postoperative day.

RESULTS

CRP median values were similar in both groups. WBC and PCT median values were significantly higher in patients with infection than without during the first 10 postoperative days. With elevation cutoffs ≤3 times (OR: 4.058; 95% CI: 2.206-7.463; P = 0.001) and ≥4 times (OR: 10.274, 95% CI: 3.690-28.604; P < 0.001), the median value for PCT (1.7 ng/mL) and/or WBC (13,000 cells/mm³) on the second postoperative day was significantly associated with the development of infection.

CONCLUSIONS

The goal of this study was to use a large cohort of cardiac surgery patients to ensure that the results were representative of this population. The combination of PCT and WBC levels over the first three postoperative days was able to predict postoperative infection within the 30 d following cardiac surgery.

[Cardiac biomarkers in perioperative risk stratification]

OBJECTIVES

The field of new cardiac biomarkers has triggered physicians' enthusiasm because of their potential diagnostic and prognostic values for routine clinical practice in the surgical setting. The objective of the present article is to review the role of new cardiac biomarkers and their potential additive clinical value in predicting short- and long-term risk following cardiac and non-cardiac surgery.

DATA SOURCES

A PubMed(®) database research in English and French languages published until June 2010. Keywords were cardiac biomarkers, troponins, cardiac troponin I (cTnI), natriuretic peptides, B-type natriuretic peptide (BNP), C-reactive protein (CRP), multiple markers approach, risk stratification, clinical risk scores.

DATA SYNTHESIS

Numerous publications deal with the diagnostic and prognostic values of new cardiac biomarkers in cardiac and non-cardiac surgical settings and provide an increasing evidence of their interest, validating different hierarchical steps which are mandatory before recommending a wide use of biomarkers for routine practice. Even if the first studies demonstrating an additional prognostic value of serum postoperative cTnI and/or preoperative BNP when compared with clinical predictive models are now available, we still lack data concerning an actual positive impact of new biomarkers measurements on clinical decision making or practice, as well as patient care and outcome.

CONCLUSIONS

While use of new cardiac biomarkers in the perioperative period appears to be a simple and objective tool for risk stratification at the bedside, we still need to remain cautious concerning their additional clinical value on existing predictive models for routine practice.