Cardiac Output Monitoring: Validation Studies–how Results Should be Presented

Cardiac Output Monitoring: Validation Studies–how Results Should be Presented

Purpose of Review Cardiac output monitors can be assessed by a variety of techniques, but a common principle is quantifying agreement between a reference standard and new monitor. The current standard analysis technique is a Bland-Altman plot. The Bland-Altman plot evaluates bias between mean differences of cardiac output, from which an agreement interval is derived. These limits are, however, ...

Continuous blood pressure-derived cardiac output monitoring--should we be thinking long term?

Continuous blood pressure-derived cardiac output monitoring—should we be thinking long term? Cardiac output, along with cardiac filling pressure, arterial blood pressure, and heart rate, is one of the most important hemodynamic variables to monitor continuously in patients with compromised cardiovascular performance. This point is illustrated strikingly in Fig. 1, which shows an example of seve...

Cardiac Output Monitoring

Should Output-Output Correspondence be Invoked to Account for Analogy?

A guiding principle of all scientific inquiry is that the power of a theory should be extended only if such an extension leads to greater insight than a more constrained theory. This principle, which goes by the name of Occam’s Razor, should be applied to the problem of constraining the set of universal constraints in an Optimality Theoretic (OT) model of grammar. Recent work in OT has seen a b...

Non-invasive cardiac output monitoring.

Outcomes in the management of critically ill patients may be improved using goal-directed peri-operative haemodynamic monitoring. A conservative approach may no longer be acceptable but in view of the significant morbidity associated with balloon tipped flow directed pulmonary artery catheters a non-invasive approach would be preferable. In this review we consider the different non-invasive tec...