Prognostic value of noninvasive measures of contractility in emergency department patients with severe sepsis and septic shock undergoing early goal-directed therapy.
OBJECTIVE
Reversible ventricular dysfunction is common in sepsis. Impedance cardiography allows for noninvasive measurement of contractility through time interval or amplitude-based measures. This study evaluates the prognostic capacity of these measures in patients with severe sepsis or septic shock in the emergency department.


METHODS
This is a prospective observational cohort study of 56 patients older than 18 years meeting criteria for early goal-directed therapy (lactate level >4 mmol/L or systolic blood pressure <90 mm Hg after 2-L isotonic sodium chloride solution). Continuous collections of contractility measures were performed, and patients were followed until discharge or in-hospital death.


RESULTS
A significant 57% reduction in the accelerated contractility index (ACI) in nonsurvivors (71 1/s(2) [41-102]) compared with survivors (123 1/s(2) [98-147]) existed. Only ACI predicted in-hospital mortality (area under the receiver operating characteristic curve = 0.70, P < .01). Accelerated contractility index did not correlate with amount of prior fluid administration, central venous pressure, number of cardiac risk factors, or troponin I value. An ACI of less than 40 1/s(2) is 95% (84-99) specific with a positive likelihood ratio of 8.8 for predicting in-hospital mortality.


CONCLUSIONS
A reduced ACI is associated with mortality in critically ill emergency department patients presenting with severe sepsis and septic shock meeting criteria for early goal-directed therapy. This association appears to be independent of clinical or laboratory predictors of cardiac dysfunction or preload.
Napoli
Anthony M
AM
Department of Emergency Medicine, Brown University Medical School, Providence, RI 02903, USA. anapoli@lifespan.org
Corl
Keith
K
Gardiner
Fenwick
F
Forcada
Ahteri
A
D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure / Q000502:physiology; D002307:Cardiography, Impedance / Q000379:methods*; D016638:Critical Illness; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D005500:Follow-Up Studies; D017052:Hospital Mortality; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology*; D011379:Prognosis; D011446:Prospective Studies; D012772:Shock, Septic / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy; D016896:Treatment Outcome
D019344:Lactic Acid