Dynamic arterial elastance predicts mean arterial pressure decrease associated with decreasing norepinephrine dosage in septic shock

Abstract

IntroductionGradual reduction of the dosage of norepinephrine (NE) in patients with septic shock is usually left to the physician’s discretion. No hemodynamic indicator predictive of the possibility of decreasing the NE dosage is currently available at the bedside. The respiratory pulse pressure variation/respiratory stroke volume variation (dynamic arterial elastance (Eadyn)) ratio has been proposed as an indicator of vascular tone. The purpose of this study was to determine whether Eadyn can be used to predict the decrease in arterial pressure when decreasing the NE dosage in resuscitated sepsis patients.MethodsA prospective study was carried out in a university hospital intensive care unit. All consecutive patients with septic shock monitored by PICCO2 for whom the intensive care physician planned to decrease the NE dosage were enrolled. Measurements of hemodynamic and PICCO2 variables were obtained before/after decreasing the NE dosage. Responders were defined by a >15% decrease in mean arterial pressure (MAP).ResultsIn total, 35 patients were included. MAP decreased by >15% after decreasing the NE dosage in 37% of patients (n = 13). Clinical characteristics appeared to be similar between responders and nonresponders. Eadyn was lower in responders than in nonresponders (0.75 (0.69 to 0.85) versus 1 (0. 83 to 1.22), P <0.05). Baseline Eadyn was correlated with NE-induced MAP variations (r = 0.47, P = 0.005). An Eadyn less than 0.94 predicted a decrease in arterial pressure, with an area under the receiver-operating characteristic curve of 0.87 (95% confidence interval (95% CI): 0.72 to 0.96; P <0.0001), 100% sensitivity, and 68% specificity.ConclusionsIn sepsis patients treated with NE, Eadyn may predict the decrease in arterial pressure in response to NE dose reduction. Eadyn may constitute an easy-to-use functional approach to arterial-tone assessment, which may be helpful to identify patients likely to benefit from NE dose reduction.

Dynamic arterial elastance measured by uncalibrated pulse contour analysis predicts arterial-pressure response to a decrease in norepinephrine

“…14e16 In studies assessing the effect of vasopressors, Ea dyn was demonstrated to change while CO did not change. 3,4,14 Ea dyn was demonstrated to be associated to cardiac factors (HR and peak of velocity of aortic blood flow) and vascular factors (arterial compliance and vascular resistance). 3,16 Moreover, no study has demonstrated an association between CO and Ea dyn .…”

“…0.90) to distinguish responders from non-responders is close to the previously demonstrated value. 3 One important question remains the physiological significance of Ea dyn . This parameter was initially described as a functional dynamic approach of vascular tone.…”

“…1,2 Dynamic arterial elastance (Ea dyn ) has been proposed as an indicator of arterial tone that can predict NE-dependent arterial pressure. 3 Ea dyn is calculated using the ratio of respiratory pulse-pressure variation (PPV) over the respiratory stroke volume variation (SVV). Guinot and colleagues 4 demonstrated a decrease in the duration of NE treatment with the use of Ea dyn .…”

“…Guinot and colleagues 4 demonstrated a decrease in the duration of NE treatment with the use of Ea dyn . 4 To date, studies that have validated Ea dyn at bedside have used cardiac-output (CO) calibrated pulse contour analysis 3 (PiCCO™ and PULSION™) or oesophageal Doppler. 5 Such monitoring systems need dedicated and specific arterial line and venous access that may limit their use at bedside.…”

Cortico-therapy in a dog with septic shock not responsive to vasopressors: A case report

“…Assim, seguindo a recomendação de Lopes et al (2010) iniciou-se a reposição volêmica com uso de cristaloide porém sem sucesso, pois não conseguiu-se a estabilização da pressão arterial sistólica (PAS). Contudo, iniciou-se a infusão contínua de norepinefrina e dobutamina, conforme descrito no protocolo da Campanha de Sobrevivência à Sepse (Surviving Sepsis Campaign), devido esta ser o vasopressor de primeira escolha para pacientes em choque séptico, pois promove ação vasoconstritora sistêmica pela ativação de receptores α-adrenérgicos (Guinot et al, 2015). A associação do inotrópico positivo, no caso dobutamina, foi realizada neste paciente com o objetivo de elevação do débito cardíaco.…”