The role of procalcitonin and N-terminal pro-B-type natriuretic peptide in predicting outcome after cardiac surgery

Higher incidence of acute respiratory distress syndrome in cardiac surgical patients with elevated serum procalcitonin concentration: a prospective cohort study

BACKGROUND

Inflammatory response is activated during cardiopulmonary bypass (CPB), which may lead to acute respiratory distress syndrome (ARDS) and procalcitonin (PCT) increases during this inflammatory response. The objective of the study was to validate whether patients with higher serum PCT concentrations have a higher incidence of ARDS.

METHODS

The study was a prospective, single-center, observational cohort study. All patients who received cardiac surgery with CPB were screened for study eligibility. Patients were assigned to the PCT-elevated cohort or the control cohort according to serum PCT concentration on the first postoperative day with a cut-off value of 7.0 ng/mL. Patients were followed up until the 7th postoperative day. The primary endpoint was the incidence of ARDS, which was diagnosed according to the Berlin definition.

RESULTS

A total of 296 patients were enrolled, 64 patients were assigned to the PCT-elevated cohort and 232 patients were assigned to the control cohort. PCT concentration was 16.23 ± 5.9 ng/mL in the PCT-elevated cohort, and 2.70 ± 1.43 ng/mL in the control cohort (p < 0.001). The incidence of ARDS was significantly higher in the PCT-elevated cohort than in the control cohort (21.9% versus 5.6%, p < 0.001). The incidence of moderate-to-severe ARDS was also significantly higher in the PCT-elevated cohort than in the control cohort (10.9% versus 0.4%, p < 0.001). The hazard ratio of ARDS at 7 days in the PCT-elevated cohort, as compared with the control cohort, was 6.8 (95% confidence interval 2.7 to 17.4). The hazard ratio of moderate-to-severe ARDS in the PCT-elevated cohort was 57.3 (95% confidence interval 10.4 to 316.3). The positive predictive value of PCT for ARDS and moderate-to-severe ARDS were 0.242 and 0.121, respectively; the negative predictive value of PCT for ARDS and moderate-to-severe ARDS were 0.952 and 1.0, respectively.

CONCLUSION

Cardiac surgical patients with elevated PCT concentration have a higher incidence of ARDS. Elevated PCT may serve as a warning signal of postoperative ARDS in patients undergoing cardiac surgery with CPB. Study registration Chinese Clinical Trial Registry (ChiCTR-OCH-14005076).

Influence of the postoperative inflammatory response on cognitive decline in elderly patients undergoing on-pump cardiac surgery: a controlled, prospective observational study

Background

The role of non-infective inflammatory response (IR) in the aetiology of postoperative cognitive dysfunction (POCD) is still controversial. The aim of this controlled, prospective observational study was to assess the possible relationship between the grade of IR, defined by procalcitonin (PCT) changes, and development of POCD related to cardiac surgery.

Methods

Forty-two patients, who were ≥ 60 years of age and scheduled for elective cardiac surgery, were separated into the low inflammatory (LIR) and high inflammatory (HIR) response groups based on their PCT levels measured on the first postoperative day. A matched normative control group of 32 subjects was recruited from primary care practice. The PCT and C-reactive protein (CRP) levels were monitored daily during the first five postoperative days. The cognitive function and mood state were preoperatively tested with a set of five neurocognitive tests and two mood inventories and at the seventh postoperative day. The Reliable Change Index modified for practice (RCIp) using data from normative controls was applied to determine the significant decline in test performance.

Results

The LIR (n = 20) and HIR (n = 22) groups differed significantly in the PCT (p < 0.001) but not in the CRP time courses. The incidence of POCD at the first postoperative week was 35.7% in the cohort. The LIR and HIR groups did not vary in the RCIp Z scores of neurocognitive tests and frequencies of POCD (7 vs 8 cases, respectively, p > 0.05). Additionally, there was no difference in the mood states, anxiety levels and perioperative parameters known to influence the development of POCD.

Conclusions

In this study, the magnitude of the non-infective inflammatory response generated by on-pump cardiac surgery did not influence the development of POCD in the early postoperative period in elderly patients.

The effect of anesthesia method on serum level of pro-brain natriuretic Peptide in patients undergoing orthopedic surgery

Background:

Surgical stress response is among the most severe stress tolerated by the patient, which needs suppression by anesthesia.

Objectives:

We assessed the effect of three methods of anesthesia on postoperative levels of pro-brain natriuretic peptide (pro-BNP) to determine the most effective one in preventing surgical stress response.

Patients and Methods:

In a randomized clinical trial, 120 patients who were 18 to 65 years old and met inclusion and exclusion criteria were selected and randomly allocated to three groups of 40:Group A, general anesthesia plus epidural catheter; Group B, general anesthesia and intravenous patient-controlled analgesia; and Group C, spinal anesthesia plus intravenous patient-controlled analgesia.

Results:

There was no difference between three groups for basic characteristics and variables and baseline pro-BNP levels; however, postoperative pro-BNP levels in Groups A, B, and C were respectively63.8 ± 10.1, 83.2 ± 12.3, and 51.5 ± 8.5 ng/L (ANOVA, P = 0.01).

Conclusions:

The results of the current study suggested that spinal anesthesia plus intravenous patient-controlled analgesia have the most favorable cardiac effects regarding postoperative levels of pro-BNP.

Procalcitonin as a predictor of moderate to severe acute respiratory distress syndrome after cardiac surgery with cardiopulmonary bypass: a study protocol for a prospective cohort study

INTRODUCTION

Procalcitonin (PCT) is activated during cardiopulmonary bypass (CPB) and may be a predictor of acute respiratory distress syndrome (ARDS). The objective of this study is to determine whether patients with different serum PCT concentrations exhibit different rates of developing moderate to severe ARDS.

METHODS AND ANALYSIS

This is a prospective, single centre, observational cohort study. All patients admitted to the cardiosurgery department for cardiac surgery with CPB were screened for study eligibility. All eligible patients received a CPB procedure. Blood samples were obtained to determine white cell counts as well as N-terminal pro-B-type natriuretic peptide, C reactive protein and PCT levels. Patients were assigned to the PCT elevated cohort or the control cohort based on serum PCT concentrations on the first postoperative day with a cut-off value of 7.0 ng/mL. Data, including baseline, perioperative and outcome data, were collected daily for 7 days. The primary end point was the incidence of moderate to severe ARDS, which was diagnosed according to the Berlin definition.

ETHICS AND DISSEMINATION

The study was approved by the Institutional Review Board of Fujian Provincial Hospital. Study findings are disseminated through peer-reviewed publications and conference presentations.

STUDY REGISTRATION

Chinese Clinical Trial Registry (ChiCTR-OCH-14005076).

Alpha lipoic acid attenuates inflammatory response during extracorporeal circulation

Aim

Extracorporeal circulation (ECC) of blood during cardiopulmonary surgery has been shown to stimulate various pro-inflammatory molecules such as cytokines and chemokines. The biochemical oxidation/reduction pathways of a-lipoic acid suggest that it may have antioxidant properties.

Methods

In this study we aimed to evaluate only patients with coronary heart disease and those planned for coronary artery bypass graft operation. Blood samples were obtained from the patients before the operation (P1) and one (P2), four (P3), 24 (P4) and 48 hours (P5) after administration of a-lipoic acid (LA). The patients were divided into two groups, control and LA treatment group. Levels of interleukin-6 (IL-6) and -8 (IL-8), complement 3 (C3) and 4 (C4), anti-streptolysin (ASO), C-reactive protein (CRP) and haptoglobin were assessed in the blood samples.

Results

Cytokine IL-6 and IL-8 levels were significantly higher after surgery. Compared with the control groups, LA significantly decreased IL-6 and IL-8 levels in a time-dependent manner. CRP levels did not show significant variation in the first three time periods. CRP levels were higher after surgery, especially in the later periods. These results demonstrate that CRP formation depends on cytokine release. C3 and C4 levels were significantly higher after surgery than in the pre-operative period. LA treatment decreased C3 and C4 levels. Therefore, LA administration may be useful for the treatment of diseases and processes where excessive cytokine release could cause oxidative damage.

Conclusions

Our findings suggest a possible benefit of using LA during cardiac surgery to reduce cytokine levels.