Oh! My beating heart…

What fortuitous timing that we should be covering cardiac intensive care during February, our National Heart Health Month! There was a smorgasbord of articles to choose from, but I was drawn to one on hemodynamics since just spent a good week or so completely immersed in that wild and wooly world…

Since 1996, pulmonary artery catheters, once considered the gold standard in hemodynamic monitoring, have been falling out of favor due to mounting, yet inconclusive, research finding that they are associated with increased likelihood of patient death. Central venous pressure monitoring has similarly been found to have minimal effect on patient outcomes when treating shock, compared to the use of conventional fluid replacement protocols (Johnson & Ahrens, 2015). Rather, Johnson & Ahrens (2015) propose that effective hemodynamic management of critically ill patients is best achieved by focusing on stroke volume optimization.

Stroke volume is the earliest and most reliable sign of hypovolemia because it is least affected by compensatory mechanisms, and the most effective means by which to measure stroke volume while maintaining the context of preload, contractility and afterload, is esophageal Doppler imaging (Johnson & Ahrens, 2015). This article proposes that correction of hypovolemia is best achieved through stroke volume optimization (SVO), a type of cyclic fluid replacement algorithm that recommends administration of fluid boluses for improvement of stroke volume by increments of 10% or more. When stroke volumes no longer increase by the full 10%, no more fluid is needed (Johnson & Ahrens, 2015). Hemodynamic monitoring of SVO protocol utilizes esophageal Doppler imaging, (or other indirect methods measuring cardiac output when contraindicated) (Johnson & Ahrens, 2015).

Implementation of SVO is supported by 11 large-scale, randomized controlled trials conducted by agencies such as the National Health Service, the Agency for Healthcare Research and Quality, the Centers for Medicare and Medicaid Services and Aetna. And though esophageal Doppler imaging, bioimpedance, and pulmonary artery catheters are all reimbursed by Centers for Medicare and Medicaid Services, esophageal Doppler monitoring is the only one of these endorsed by the Agency for Healthcare Research and Quality (Johnson & Ahrens, 2015).

I just can’t wait until next week when I have my very first day in ICU…

Reference

Johnson, A., & Ahrens, T., (2015). Stroke volume optimization: The new hemodynamic algorithm. Critical Care Nurse (35)1: 11-27.