Vital Times 2020 - 66

Figure 3. ClearSight finger cuff model with self-coiling mechanism within the interior of the cuff that wraps around the finger.

Studies comparing CO measured by a pulse contour
device (ClearSight, Edwards Lifesciences, Irvine, CA)
to direct PAC measurements demonstrated a >90%
concordance and accuracy of 84-100%, indicating
a strong correlation between ClearSight and PAC
measures.2,16 A randomized trial showed that noninvasive continuous blood pressure monitoring during
orthopedic surgery was associated with greater blood
pressure stability and significantly fewer hypotensive
episodes as compared to only monitoring non-invasive
blood pressure. When hypotension did occur, it was
detected and treated earlier with the continuous
non-invasive device.17 Another study demonstrated
significant correlation between CO values obtained
with non-invasive finger pulse contour analysis and
the transpulmonary thermodilution technique.18
However, some limitations with finger-cuff devices
include distorted signals in patients with finger edema
or peripheral hypoperfusion, as well as unreliable
measurements in cardiogenic and hypovolemic
shock.14
Non-invasive hemodynamic management strategies
can be potentially applied to patients for whom
arterial or pulmonary arterial catheters would typically

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not be placed or contraindicated. For instance,
non-invasive devices may provide greater insight to
hemodynamic function in patients undergoing low
or intermediate-risk surgery, neuraxial or regional
anesthesia, and in patients with active catheter
infections. Additionally, continuous hemodynamic
monitoring has become increasingly important
with the rising prevalence of heart disease and
comorbidities, especially within an aging surgical
population.
Introducing non-invasive devices into the preoperative
evaluation may prove useful for guiding optimization
prior to surgery and ultimately guiding intraoperative
management. By establishing individualized " normal
ranges " for blood pressure, dynamic cardiac
preload, and CO, practitioners can develop an
individualized framework for managing intraoperative
hemodynamics. Personalized blood pressure
management helps maintain cerebral blood flow as
autoregulation is affected by chronic hypertension, in
which case both the upper and lower limits of cerebral
autoregulation are shifted towards higher pressures,
predisposing patients to cerebral hypoperfusion.
With this approach, hemodynamic goals are
Vital Times 2020

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