Perioperative B-type Natriuretic Peptide/ N -terminal pro-B-type Natriuretic Peptide

NT-proBNP in young healthy adults undergoing non-cardiac surgery

OBJECTIVES

N-terminal pro-brain natriuretic peptide (NT-proBNP), a standard marker for diagnosis and treatment guidance of heart failure, has previously been investigated in high-risk patients undergoing cardiac and non-cardiac surgery. However, the kinetics of NT-proBNP in healthy patients undergoing non-cardiac surgery are unknown.

DESIGN & METHODS

A secondary analysis of a prospective cohort study was conducted. NT-proBNP plasma concentrations were measured preoperatively, 2-6 h, and 18-30 h after surgery in 120 patients, 18-35 years, undergoing elective non-cardiac surgery. Reasons for non-inclusion: history or symptoms of cardiac disease, kidney disease, pulmonary embolism, thrombosis, stroke, diabetes, head or chest trauma, pregnancy, incomplete panel of perioperative NT-proBNP plasma samples. Absolute and relative change of NT-proBNP plasma concentration were calculated. Changes between preoperative, 2-6 h, and 18-30 h (POD 1) NT-proBNP values, and of within-patient change in NT-proBNP were analyzed.

RESULTS

In 95 patients, NT-proBNP plasma concentrations (median [IQR]) were 8 [5-26] pg/mL at baseline, 17 [5-53] pg/mL 2-6 h, and 42 [11-86] pg/mL 18-30 h after surgery. Absolute and relative NT-proBNP increase after surgery was 32 [5-74] pg/mL and 196% [61 - 592%] compared to baseline. NT-proBNP elevation above the age- and sex-specific reference range was observed in 6/95 (6%) patients prior to surgery and in 39/95 (41%) patients after surgery.

CONCLUSIONS

Even after uncomplicated surgery and postoperative period, NT-proBNP concentrations markedly increase in otherwise healthy adult patients. The aetiology of postoperative NT-proBNP increase is currently unknown and may be multifactorial.

Biomarker dynamics in cardiac surgery: a prospective observational study on MR-proADM, MR-proANP, hs-CRP and sP-selectin plasma levels in the perioperative period

Background: For many biomarkers in cardiac surgery, there is a lack of knowledge regarding the normal dynamics of plasma levels during the perioperative course. The aim of this study was to investigate the perioperative dynamics of MR-proADM, MR-proANP, hs-CRP and sP-selectin in cardiac surgery.Method: A prospective observational pilot study with 20 patients scheduled for open cardiac surgery procedures with cardiopulmonary bypass (CPB). Plasma samples were taken for each patient and biomarker during the pre-, per- and postoperative period until Day 6 postoperatively.Results: MR-proADM increased significantly from 0.62 [IQR; 0.54-0.93] nmol/L preoperatively to 1.20 [1.04-1.80] nmol/L postoperative Day 1. MR-proANP increased significantly from 125 [77-152] pmol/L preoperatively to 198 [168-307] pmol/L on weaning from CPB. hs-CRP increased significantly from 2.5 mg/L [0.4-12] preoperatively to peak at 208 mg/L [186-239] postoperative Day 3. The preoperative level of sP-selectin at 23.0 [21.3-26.3] ng/mL initially fell at weaning from CPB, followed by a significant peak of 25.5 [22.7-27.7] ng/mL 8 h postoperatively.Conclusions: The findings in this study may help to understand the physiology of the biomarkers analysed and their response to cardiac surgical trauma including CPB. Furthermore, these findings will guide us in further research on the clinical usefulness of these biomarkers.

Plasma N-terminal pro-brain natriuretic peptide concentrations before and after pericardiocentesis in dogs with cardiac tamponade secondary to spontaneous pericardial effusion

OBJECTIVE

To determine if concentrations of plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) are increased in dogs with cardiac tamponade and if there is a significant increase in plasma NT-proBNP after pericardiocentesis.

ANIMALS

Ten client-owned dogs with spontaneous cardiac tamponade.

METHODS

Prospective clinical study. Cardiac tamponade was suspected from physical examination and confirmed with echocardiography. Blood was collected and plasma NT-proBNP concentrations were measured before and 30-60 min following pericardiocentesis and resolution of cardiac tamponade. Within-subject changes in plasma NT-proBNP were compared by the Wilcoxon signed-rank test.

RESULTS

The plasma NT-proBNP concentrations measured within the reference interval in seven of 10 dogs before pericardiocentesis and in six of 10 dogs following pericardiocentesis. Following pericardiocentesis, there was a statistically significant increase in median NT-proBNP concentration (733 pmol/L, range 250-3,297) compared with the values measured before (643 pmol/L, range 250-3,210, P = 0.004). The NT-proBNP concentration increased in 90% of the dogs following pericardiocentesis.

CONCLUSIONS

An upper reference limit of 900 pmol/L for plasma NT-proBNP is insensitive for the diagnosis of pericardial effusion and cardiac tamponade in dogs. Plasma NT-proBNP concentration commonly increases following pericardiocentesis, perhaps related to improved ventricular filling and stretch.