Lower versus higher hemoglobin threshold for transfusion in ARDS patients with and without ECMO.

BACKGROUND: Efficacy and safety of different hemoglobin thresholds for transfusion of red blood cells (RBCs) in adults with an acute respiratory distress syndrome (ARDS) are unknown. We therefore assessed the effect of two transfusion thresholds on short-term outcome in patients with ARDS. METHODS: Patients who received transfusions of RBCs were identified from a cohort of 1044 ARDS patients. After propensity score matching, patients transfused at a hemoglobin concentration of 8 g/dl or less (lower-threshold) were compared to patients transfused at a hemoglobin concentration of 10 g/dl or less (higher-threshold). The primary endpoint was 28-day mortality. Secondary endpoints included ECMO-free, ventilator-free, sedation-free, and organ dysfunction-free composites. MEASUREMENTS AND MAIN RESULTS: One hundred ninety-two patients were eligible for analysis of the matched cohort. Patients in the lower-threshold group had similar baseline characteristics and hemoglobin levels at ARDS onset but received fewer RBC units and had lower hemoglobin levels compared with the higher-threshold group during the course on the ICU (9.1 [IQR, 8.7-9.7] vs. 10.4 [10-11] g/dl, P < 0.001). There was no difference in 28-day mortality between the lower-threshold group compared with the higher-threshold group (hazard ratio, 0.94 [95%-CI, 0.59-1.48], P = 0.78). Within 28 days, 36.5% (95%-CI, 27.0-46.9) of the patients in the lower-threshold group compared with 39.5% (29.9-50.1) of the patients in the higher-threshold group had died. While there were no differences in ECMO-free, sedation-free, and organ dysfunction-free composites, the chance for successful weaning from mechanical ventilation within 28 days after ARDS onset was lower in the lower-threshold group (subdistribution hazard ratio, 0.36 [95%-CI, 0.15-0.86], P = 0.02). CONCLUSIONS: Transfusion at a hemoglobin concentration of 8 g/dl, as compared with a hemoglobin concentration of 10 g/dl, was not associated with an increase in 28-day mortality in adults with ARDS. However, a transfusion at a hemoglobin concentration of 8 g/dl was associated with a lower chance for successful weaning from the ventilator during the first 28 days after ARDS onset. TRIAL REGISTRATION: ClinicalTrials.gov NCT03871166.

La respuesta de la saturación dinámica muscular en cirugía no cardiaca se altera pese a la terapia hemodinámica dirigida por objetivos / Dynamic muscle O2 saturation response is impaired during major non-cardiac surgery despite goal-directed haemodynamic therapy

Introducción. En pacientes sépticos, la espectroscopia cercana a infrarrojos combinada con un test de oclusión vascular (VOT) puede indicar alteraciones de la reactividad microvascular (RMV) detectando cambios dinámicos de la saturación de oxígeno muscular (StO2). Sin embargo, se desconocen las consecuencias del trauma quirúrgico sobre la StO2 como indicador de RMV perioperatoria. Métodos. Subanálisis de un ensayo clínico aleatorizado en pacientes con metástasis de cáncer primario de ovario sometidos a cirugía citorreductora donde se aplicó un algoritmo de terapia hemodinámica dirigida a objetivo mediante doppler esofágico. Tras un VOT de 3 min, se valoraron cambios dinámicos de la StO2 muscular mediante espectroscopia cercana a infrarrojo. Resultados. Al inicio de la cirugía, los valores de desaturación y las pendientes de recuperación de valores basales fueron comparables a los valores obtenidos en voluntarios sanos pero ambas mostraron disminuciones progresivas durante el transcurso de la misma. Simultáneamente, la población a estudio sufrió una transición a un estado de respuesta inflamatoria sistémica por estrés quirúrgico, mostrándose por un incremento progresivo de los requerimientos de norepinefrina, de la frecuencia cardiaca y de interleucina 6, y produciéndose un pico inmediatamente tras la cirugía. Las dosis altas de norepinefrina y la frecuencia cardiaca se correlacionaron con una disminución más rápida de StO2 durante el VOT. Conclusiones. El uso combinado de espectroscopia cercana a infrarrojo y VOT durante la cirugía mostró un deterioro progresivo de la RMV en pacientes hemodinámicamente tratados de forma óptima. El deterioro de la RMV se acompañó de una transición a un estado de respuesta inflamatoria sistémica inducida por cirugía (AU)

Background. Near-infrared spectroscopy combined with a vascular occlusion test (VOT) could indicate an impairment of microvascular reactivity (MVR) in septic patients by detecting changes in dynamic variables of muscle O2 saturation (StO2). However, in the perioperative context the consequences of surgical trauma on dynamic variables of muscle StO2 as indicators of MVR are still unknown. Methods. This study is a sub-analysis of a randomised controlled trial in patients with metastatic primary ovarian cancer undergoing debulking surgery, during which a goal-directed haemodynamic algorithm was applied using oesophageal Doppler. During a 3 min VOT, near-infrared spectroscopy was used to assess dynamic variables arising from changes in muscle StO2. Results. At the beginning of surgery, values of desaturation and recovery slope were comparable to values obtained in healthy volunteers. During the course of surgery, both desaturation and recovery slope showed a gradual decrease. Concomitantly, the study population underwent a transition to a surgically induced systemic inflammatory response state shown by a gradual increase in norepinephrine administration, heart rate, and Interleukin-6, with a peak immediately after the end of surgery. Higher rates of norepinephrine and a higher heart rate were related to a faster decline in StO2 during vascular occlusion. Conclusions. Using near-infrared spectroscopy combined with a VOT during surgery showed a gradual deterioration of MVR in patients treated with optimal haemodynamic care. The deterioration of MVR was accompanied by the transition to a surgically induced systemic inflammatory response state (AU)

Dynamic muscle O2 saturation response is impaired during major non-cardiac surgery despite goal-directed haemodynamic therapy.

BACKGROUND: Near-infrared spectroscopy combined with a vascular occlusion test (VOT) could indicate an impairment of microvascular reactivity (MVR) in septic patients by detecting changes in dynamic variables of muscle O2 saturation (StO2). However, in the perioperative context the consequences of surgical trauma on dynamic variables of muscle StO2 as indicators of MVR are still unknown. METHODS: This study is a sub-analysis of a randomised controlled trial in patients with metastatic primary ovarian cancer undergoing debulking surgery, during which a goal-directed haemodynamic algorithm was applied using oesophageal Doppler. During a 3 min VOT, near-infrared spectroscopy was used to assess dynamic variables arising from changes in muscle StO2. RESULTS: At the beginning of surgery, values of desaturation and recovery slope were comparable to values obtained in healthy volunteers. During the course of surgery, both desaturation and recovery slope showed a gradual decrease. Concomitantly, the study population underwent a transition to a surgically induced systemic inflammatory response state shown by a gradual increase in norepinephrine administration, heart rate, and Interleukin-6, with a peak immediately after the end of surgery. Higher rates of norepinephrine and a higher heart rate were related to a faster decline in StO2 during vascular occlusion. CONCLUSIONS: Using near-infrared spectroscopy combined with a VOT during surgery showed a gradual deterioration of MVR in patients treated with optimal haemodynamic care. The deterioration of MVR was accompanied by the transition to a surgically induced systemic inflammatory response state.

Oesophageal Doppler and calibrated pulse contour analysis are not interchangeable within a goal-directed haemodynamic algorithm in major gynaecological surgery.

BACKGROUND: Evidence for the benefit of an intraoperative use of a goal-directed haemodynamic management has grown. We compared the oesophageal Doppler monitor (ODM, CardioQ-ODM™) with a calibrated pulse contour analysis (PCA, PiCCO2™) with regard to assessment of stroke volume (SV) changes after volume administration within a goal-directed haemodynamic algorithm during non-cardiac surgery. METHODS: The data were obtained prospectively in patients with metastatic ovarian carcinoma undergoing cytoreductive surgery. During surgery, fluid challenges were performed as indicated by the goal-directed haemodynamic algorithm guided by the ODM. Monitors were compared regarding precision and trending. Clinical characteristics associated with trending were studied by extended regression analysis. RESULTS: A total of 762 fluid challenges were performed in 41 patients resulting in 1524 paired measurements. The precision of ODM and PCA was 5.7% and 6.0% (P=0.80), respectively. Polar plot analysis revealed a poor trending between ODM and PCA with an angular bias of -7.1°, radial limits of agreement of -58.1° to 43.8°, and an angular concordance rate of 67.8%. Dose of norepinephrine (NE) (scaled 0.1 µg kg(-1) min(-1)) [adjusted odds ratio (OR) 0.606 (95% confidence interval, CI: 0.404-0.910); P=0.016] and changes in mean arterial pressure (MAP) to a fluid challenge (scaled 10%) [adjusted OR 0.733 (95% CI: 0.635-0.845); P<0.001] were associated with trending between ODM and PCA, whereas there was no relation to type of i.v. solution. CONCLUSIONS: Despite a similar precision, ODM and PCA were not interchangeable with regard to measuring SV changes within a goal-directed haemodynamic algorithm. A decrease in interchangeability coincided with increasing NE levels and greater changes of MAP to a fluid challenge.