Pulse wave velocity and short-term outcome in patients requiring intravascular volume expansion: a pilot study

Fluid therapy has a pivotal role in the management of acutely ill patients. However, whether or not a patient can tolerate additional intravascular volume is controversial and optimal strategy is unknown. Carotid femoral pulse wave velocity (cfPWV) evaluates arterial stiffness.

To determine whether cfPWV can predict the ability of patients to tolerate clinically indicated acute fluid expansion.

50 consecutive patients requiring intravascular volume expansion were prospectively recruited in intensive care units. All subjects underwent transthoracic echocardiography, pulmonary ultrasound assessment, and a cfPWV study (S. Giovanni Bosco Hospital in Turin, Italy, between 2015 and 2016) at baseline and after 24 hours. Acute outcomes were registered at 24 hours ("soft" end points) and 30 days ('hard' end points: death, acute myocardial infarction, stroke, occurrence of atrial fibrillation, need for dialysis) after initial fluid therapy. Multivariate logistic regression was used to assess association of the initial cfPWV with outcomes.

cfPWV was significantly higher (10.6±3.6 vs 7.4±2.2 m/s, P<0.0001) in subjects who met the prespecified combined endpoints (hard or soft) than in those who did not. After adjustment for confounding factors, initial cfPWV was significantly and independently associated with the occurrence of hard events (OR=2.8 (95% CI 1.36 to 5.97), P=0.005; area under the receiver operating characteristic curve 84%). cfPWV of <9 m/s had a negative predictive value of 93%, excluding hard events associated with fluid expansion.

cfPWV appears to reflect the ability of the patient to tolerate an intravascular fluid expansion when clinically indicated. Increased cfPWV could help to identify subjects at greater risk of developing signs and symptoms of fluid overload.