Value of CVP: an epidemiological or physiological question?

Exploring the optimal range of central venous pressure in sepsis and septic shock patients: A retrospective study in 208 hospitals

BACKGROUND

The aim of this study was to investigate the optimal CVP range in sepsis and septic shock patients admitted to intensive care unit.

METHODS

We performed a retrospective study with adult sepsis patients with CVP records based on the eICU Collaborative Research Database. Multivariable logistic regression was performed to explore the associations between CVP level and hospital mortality. Non-linear correlations and optimal CVP range were explored using restricted cubic splines (RCS).

RESULTS

A total of 5302 sepsis patients were included in this study. Patients in 4-8 mmHg group owned the lowest odds ratio for raw hospital mortality (19.7%). The logistic regression analyses revealed that hospital death risk increased significantly when mean CVP level exceeds 12 mmHg compared to 4-8 mmHg level. U-shaped association of CVP with hospital mortality was revealed by RCS model in septic shock patients and the optimal range was 5.6-12 mmHg. While, there was a J-shaped trend for non-septic shock patients. For non-septic shock patients, patients had an increased risk of hospital death only if CVP exceeded 11 mmHg.

CONCLUSIONS

We observed U-shaped association between mean CVP level and hospital mortality in septic shock patients and J-shaped association in non-septic shock patients. This may imply that patients with different severity of sepsis have different CVP requirements. We need to monitor and manage CVP according to the circulatory status of the sepsis patient.

Perioperative hemodynamic monitoring: Still a place for cardiac filling pressures?

The clinical usefulness of the so-called "static" cardiac filling pressures - central (CVP) and pulmonary-artery-occlusion-pressure (PAOP) - has come into question for guiding hemodynamic therapy due to their poor ability to predict fluid responsiveness in comparison with other monitoring modalities such as transpulmonary thermodilution-derived volumetric measurements, dynamic variables for assessing fluid responsiveness, and the potential risks associated with pulmonary artery catheterization. This contrasts with observations in multiple patient populations showing a clear association between increased CVP and PAOP levels and poor outcomes, probably due to a reduction in effective perfusion pressure (mean arterial pressure minus CVP) and their role as effectiveness parameters of the cardiovascular system. Furthermore, clinical studies have revealed beneficial effects when interpreting CVP and PAOP dynamically and combining them with flow-related hemodynamic variables. Taking into account the additional information derived from bedside CVP and PAOP pulse curve interpretation, cardiac filling pressures remain an important hemodynamic monitoring tool.

Impact of restrictive fluid protocol on hypoxemia after aneurysmal subarachnoid hemorrhage

PURPOSE

In patients with aneurysmal subarachnoid hemorrhage (aSAH), acute cardiac dysfunction and triple-H-therapy, can lead to hypoxemia. Our aim was to assess impact of a protocoled fluid restrictive approach on hypoxemia in these patients.

METHODS

We included prospectively ICU patients with aSAH admitted within 24h after the bleed. The study was divided into 2 phases. The first phase, from January to December 2012, was designated as control group (group C). The second phase, from February 2014 to January 2015, was designated as study group (group S). Between these periods, a protocoled fluid intake approach was implemented to maintain as low as possible the cumulative fluid balances.

RESULTS

Effective fluid restriction was obtained: at day 3 cumulative fluid balances were respectively for group C and group S, 1559±2402ml and 759±1855ml (p=0.04); and 2211±4918ml vs 529±2806ml (p=0.04) at day 7. We observed reduction in proportion of hypoxemic patient in group S compared to group C, at day 3 (22% vs 40%, p=0.047) and at day 7 (28% vs 57%, p=0.007).

CONCLUSIONS

Fluid restrictive management of patients with aSAH decreases number of hypoxemic patients at day 3 and day 7.