Central venous-to-arterial PCO difference as a marker to identify fluid responsiveness in septic shock.

Defining the hemodynamic response to volume therapy is integral to managing critically ill patients with acute circulatory failure, especially in the absence of cardiac index (CI) measurement. This study aimed at investigating whether changes in central venous-to-arterial CO difference (Δ-ΔPCO) and central venous oxygen saturation (ΔScvO) induced by volume expansion (VE) are reliable parameters to define fluid responsiveness in sedated and mechanically ventilated septic patients. We prospectively studied 49 critically ill septic patients in whom VE was indicated because of circulatory failure and clinical indices.

Delayed but successful response to noninvasive ventilation in COPD patients with acute hypercapnic respiratory failure.

Background: We evaluated a new noninvasive ventilation (NIV) protocol that allows the pursuit of NIV in the case of persistent severe respiratory acidosis despite a first NIV challenge in COPD patients with acute hypercapnic respiratory failure (AHRF).

Patients And Methods: A prospective observational multicentric pilot study was conducted in three tertiary hospitals over a 12-month study period. A total of 155 consecutive COPD patients who were admitted for AHRF and treated by NIV were enrolled.

Acute hyperventilation increases the central venous-to-arterial PCO difference in stable septic shock patients.

Background: To evaluate the effects of acute hyperventilation on the central venous-to-arterial carbon dioxide tension difference (∆PCO) in hemodynamically stable septic shock patients.

Methods: Eighteen mechanically ventilated septic shock patients were prospectively included in the study. We measured cardiac index (CI), ∆PCO, oxygen consumption (VO), central venous oxygen saturation (ScvO), and blood gas parameters, before and 30 min after an increase in alveolar ventilation (increased respiratory rate by 10 breaths/min).

Ratios of central venous-to-arterial carbon dioxide content or tension to arteriovenous oxygen content are better markers of global anaerobic metabolism than lactate in septic shock patients.

Background: To evaluate the ability of the central venous-to-arterial CO2 content and tension differences to arteriovenous oxygen content difference ratios (∆ContCO2/∆ContO2 and ∆PCO2/∆ContO2, respectively), blood lactate concentration, and central venous oxygen saturation (ScvO2) to detect the presence of global anaerobic metabolism through the increase in oxygen consumption (VO2) after an acute increase in oxygen supply (DO2) induced by volume expansion (VO2/DO2 dependence).

Methods: We prospectively studied 98 critically ill mechanically ventilated patients in whom a fluid challenge was decided due to acute circulatory failure related to septic shock. Before and after volume expansion (500 mL of colloid solution), we measured cardiac index, VO2, DO2, ∆ContCO2/∆ContO2 and ∆PCO2/∆ContO2 ratios, lactate, and ScvO2.

Repeatability of blood gas parameters, PCO2 gap, and PCO2 gap to arterial-to-venous oxygen content difference in critically ill adult patients.

The objective of this study was to examine the repeatability of blood gas (BG) parameters and their derived variables such as the central venous-to-arterial carbon dioxide tension difference (▵PCO2) and the ratio of ▵PCO2 over the central arteriovenous oxygen content difference (▵PCO2/C(a-cv)O2) and to determine the smallest detectable changes in individual patients.A total of 192 patients with arterial and central venous catheters were included prospectively. Two subsequent arterial and central venous blood samples were collected immediately one after the other and analyzed using the same point-of-care BG analyzer.

Postpartum acute renal failure: a multicenter study of risk factors in patients admitted to ICU.

Background: Even in developed countries, severe specific pregnancy complications may occur in the immediate postpartum period and require admission to the ICU. The characteristics and risk factors of acute renal failure (ARF) induced by these complications and their treatments are not well known.

Methods: We performed a retrospective multicenter study in three intensive care departments linked to level III maternity wards in the north of France.

Determinants of noninvasive ventilation success or failure in morbidly obese patients in acute respiratory failure.

Purpose: Acute respiratory failure (ARF) is a common life-threatening complication in morbidly obese patients with obesity hypoventilation syndrome (OHS). We aimed to identify the determinants of noninvasive ventilation (NIV) success or failure for this indication.

Methods: We prospectively included 76 consecutive patients with BMI>40 kg/m2 diagnosed with OHS and treated by NIV for ARF in a 15-bed ICU of a tertiary hospital.

Central venous-to-arterial carbon dioxide partial pressure difference in early resuscitation from septic shock: a prospective observational study.

Background: Central venous-to-arterial carbon dioxide partial pressure difference (ΔPCO2) can be used as a marker for the efficacy of venous blood in removing the total CO2 produced by the tissues. To date, this role of ΔPCO2 has been assessed only in patients after resuscitation from septic shock with already normalised central venous oxygen saturation (ScvO2 ≥70%). There are no reports on the behaviour of ΔPCO2 and its relationship to cardiac index (CI) and clinical outcome before normal ScvO2 has been achieved.

Time course of central venous-to-arterial carbon dioxide tension difference in septic shock patients receiving incremental doses of dobutamine.

Purpose: To assess the time course of the central venous-arterial carbon dioxide tension difference (∆PCO2)-as an index of the carbon dioxide production (VCO2)/cardiac index (CI) ratio-in stable septic shock patients receiving incremental doses of dobutamine.

Methods: Twenty-two hemodynamically stable septic shock patients with no signs of global tissue hypoxia, as testified by normal blood lactate levels, were prospectively included. A dobutamine infusion was administered at a dose of up to 15 μg/kg/min in increments of 5 μg/kg/min every 30 min.

Effects of sitting position and applied positive end-expiratory pressure on respiratory mechanics of critically ill obese patients receiving mechanical ventilation*.

Objective: To evaluate the extent to which sitting position and applied positive end-expiratory pressure improve respiratory mechanics of severely obese patients under mechanical ventilation.

Design: Prospective cohort study.

Settings: A 15-bed ICU of a tertiary hospital.

Use of sodium-chloride difference and corrected anion gap as surrogates of Stewart variables in critically ill patients.

Introduction: To investigate whether the difference between sodium and chloride ([Na(+)] - [Cl(-)]) and anion gap corrected for albumin and lactate (AG(corr)) could be used as apparent strong ion difference (SID(app)) and strong ion gap (SIG) surrogates (respectively) in critically ill patients.

Methods: A total of 341 patients were prospectively observed; 161 were allocated to the modeling group, and 180 to the validation group. Simple regression analysis was used to construct a mathematical model between SID(app) and [Na(+)] - [Cl(-)] and between SIG and AG(corr) in the modeling group.

Rescue therapy by switching to total face mask after failure of face mask-delivered noninvasive ventilation in do-not-intubate patients in acute respiratory failure.

Objective: To evaluate the impact of switching to total face mask in cases where face mask-delivered noninvasive mechanical ventilation has already failed in do-not-intubate patients in acute respiratory failure.

Design And Setting: Prospective observational study in an ICU and a respiratory stepdown unit over a 12-month study period.

Intervention: Switching to total face mask, which covers the entire face, when noninvasive mechanical ventilation using facial mask (oronasal mask) failed to reverse acute respiratory failure.

The repeatability of Stewart's parameters and anion gap in a cohort of critically ill adult patients.

Purpose: To examine the repeatability of Stewart's parameters and anion gap in a cohort of critically ill patients and to determine the smallest detectable changes in individual patients.

Methods: A total of 161 patients were included prospectively. They underwent two subsequent blood samplings within 10 min of each other and samples were analyzed using the same central laboratory analyzer.

Extravascular lung water indexed or not to predicted body weight is a predictor of mortality in septic shock patients.

Purpose: The purpose was to investigate whether extravascular lung water (EVLW) indexed to actual body weight (EVLWa) is an independent predictor of mortality in patients with septic shock, to determine the relationship between EVLWa and other markers of lung injury, and to test if indexing EVLW with predicted body weight (EVLWp) strengthens its predictive power.

Methods: Extravascular lung water, pulmonary vascular permeability index, and other markers of lung injury were measured prospectively in 55 patients with septic shock for 3 days.

Results: At day 1, EVLWa, EVLWp, and pulmonary vascular permeability index were not significantly different between survivors and nonsurvivors.

Pretreatment with peroxysome proliferator-activated receptor alpha agonist fenofibrate protects endothelium in rabbit Escherichia coli endotoxin-induced shock.

Objective: To investigate the effects of fenofibrate, an activator of peroxysome proliferator activated receptor (PPAR) alpha, on vascular endothelium and on hemostasis in a rabbit endotoxic shock model.

Design And Setting: Prospective laboratory study in a university laboratory.

Subjects: 36 male New Zealand rabbits weighing 2.

Beneficial effect of pharmacological mobilization of bone marrow in experimental cerebral ischemia.

Bone marrow stem cells are able to differentiate into nervous and endothelial cells. In our study, we found that administration of a bone marrow-stimulating factor (granulocyte colony-stimulating factor; G-CSF 50 microg/kg) decrease the brain infarct volume and enhance survival rate in a model of cerebral ischemia. Taken together, these data suggest a beneficial effect of a pharmacological endogenous bone marrow mobilization in the course of cerebral ischemia and open a new direction for cellular therapy strategy in stroke.