Positive End-Expiratory Pressure Ventilation Decreases Plasma Atrial and Brain Natriuretic Peptide Levels in Humans

Abstract

To investigate the possible role of atrial and brain natriuretic peptides (ANP and BNP) in the renal effects of mechanical ventilation with positive end-expiratory pressure (PEEP), we measured changes in plasma ANP and BNP levels during PEEP in patients undergoing subtotal esophagectomy. Application of 15 cm of H2O PEEP for 1 h decreased the levels of plasma ANP and BNP from 24.4 +/- 5.5 (mean +/- SEM) and 19.0 +/- 3.5 fmol/mL to 14.4 +/- 2.1 and 15.3 +/- 3.0 fmol/mL, respectively (P < 0.05). The level of plasma cyclic guanosine monophosphate, an intracellular second messenger of ANP and BNP, also decreased from 8.4 +/- 1.5 to 5.7 +/- 0.8 pmol/mL (P < 0.05). PEEP increased the levels of plasma arginine vasopressin from 2.0 +/- 0.5 to 4.2 +/- 1.2 pg/mL, aldosterone from 36.1 +/- 4.9 to 65.3 +/- 12.7 pg/mL, and plasma renin activity from 1.4 +/- 0.5 to 2.7 +/- 0.7 ng.mL-1.h-1. During PEEP ventilation, urine output, urinary sodium and potassium excretion, osmolar clearance, and cardiac index all decreased. PEEP increased free water clearance, right atrial pressure, pulmonary arterial pressure, and pulmonary capillary wedge pressure. The level of plasma endothelin, mean blood pressure, and heart rate did not change significantly. These results suggest that not only hemodynamics and the vasopressin and renin-angiotensin-aldosterone system, but also the natriuretic peptide system (ANP and BNP), are involved in the renal effects of PEEP.

High frequency jet ventilation is associated with increased levels of plasma α-atrial natriuretic peptide — a preliminary study

“…Many experimental and clinical studies have demonstrated that the decrease in urine output induced by PEEP is mediated in part by a decrease in the secretion of α-ANP, secondary to a reduction in the atrial transmural pressure. 2 In contrast, as shown in the present study, HFJV increased the plasma α-ANP concentration and the urine output.…”

“…1 Recent studies have suggested that a decrease in the plasma ANP concentration contributes to the renal effects of controlled mechanical ventilation (CMV) with positive end-expiratory pressure (PEEP). [2][3][4] On the other hand, the authors have observed that polyuria has often been observed during high frequency jet ventilation (HFJV). However, little is known about the effects of HFJV on the plasma concentration of ANP and renal function.…”

Prediction of hospital outcome in septic shock: a prospective comparison of tissue Doppler and cardiac biomarkers

“…However, elevated BNP appears to lack validity as a biomarker of myocardial dysfunction in sepsis. Potential explanations include inflammation [38], altered clearance [57], altered intrathoracic pressures/mechanical ventilation [58], vasoactive and inotropic drugs [37], fluid management [36,59], and diastolic dysfunction [40]. …”

A Comparison of Transcutaneous Doppler Corrected Flow Time, B-Type Natriuretic Peptide and Central venous Pressure as Predictors of Fluid Responsiveness in Septic Shock: A Preliminary Evaluation.

“…extremely high BNP concentrations have been reported in septic patients, even in the presence of preserved left ventricular systolic function 20 . The precise cause of this is unclear but may be due to several potential confounders, including inflammation 21,22 , impaired clearance 5 and commonly employed therapies such as altered intrathoracic pressures/ mechanical ventilation 23 and the use of vasoactive and inotropic drugs 24 . In keeping with previous data, static values of CVP did not predict haemodynamic response to fluid challenge 7 .…”