Activated protein C ameliorates coagulopathy but does not influence outcome in lethal H1N1 influenza: a controlled laboratory study

Introduction

Discrepancies of 5-24% between superior vena cava oxygen saturation (ScvO₂) and mixed venous oxygen saturation (SvO₂) have been reported in patients with severe heart failure. Thenar muscle tissue oxygenation (StO₂) measured with near-infrared spectroscopy (NIRS) during arterial occlusion testing decreases slower in sepsis/septic shock patients (lower StO₂ deoxygenation rate). The StO₂ deoxygenation rate is influenced by dobutamine. The aim of this study was to determine the relationship between the StO₂ deoxygenation rate and the ScvO₂-SvO₂ discrepancy in patients with severe left heart failure and additional sepsis/septic shock treated with or without dobutamine.

Methods

Fifty-two patients with severe left heart failure due to primary heart disease with additional severe sepsis/septic shock were included. SvO₂ and ScvO₂ were compared to the thenar muscle StO₂ before and during arterial occlusion.

Results

SvO₂ correlated significantly with ScvO₂ (Pearson correlation 0.659, P = 0.001), however, Bland Altman analysis showed a clinically important difference between both variables (ScvO₂-SvO₂ mean 72 ± 8%, ScvO₂-SvO₂ difference 9.4 ± 7.5%). The ScvO₂-SvO₂ difference correlated with plasma lactate (Pearson correlation 0.400, P = 0.003) and the StO₂ deoxygenation rate (Pearson correlation 0.651, P = 0.001). In the group of patients treated with dobutamine, the ScvO₂-SvO₂ difference correlated with plasma lactate (Pearson correlation 0.389, P = 0.011) and the StO₂ deoxygenation rate (Pearson correlation 0.777, P = 0.0001).

Conclusions

In patients with severe heart failure with additional severe sepsis/septic shock the ScvO₂-SvO₂ discrepancy presents a clinical problem. In these patients the skeletal muscle StO₂ deoxygenation rate is inversely proportional to the difference between ScvO₂ and SvO₂; dobutamine does not influence this relationship. When using ScvO₂ as a treatment goal, the NIRS measurement may prove to be a useful non-invasive diagnostic test to uncover patients with a normal ScvO₂ but potentially an abnormally low SvO₂.

Trial Registration

NCT00384644 ClinicalTrials.Gov.     

Central venous O2 saturation and venous-to-arterial CO2 difference as complementary tools for goal-directed therapy during high-risk surgery

Introduction  

Central venous oxygen saturation (ScvO₂) is a useful therapeutic target in septic shock and high-risk surgery. We tested the hypothesis that central venous-to-arterial carbon dioxide difference (P(cv-a)CO₂), a global index of tissue perfusion, could be used as a complementary tool to ScvO₂ for goal-directed fluid therapy (GDT) to identify persistent low flow after optimization of preload has been achieved by fluid loading during high-risk surgery.     

No agreement of mixed venous and central venous saturation in sepsis,independent of sepsis origin

Introduction  

Controversy remains regarding the relationship between central venous saturation (ScvO₂) and mixed venous saturation (SvO₂) and their use and interchangeability in patients with sepsis or septic shock. We tested the hypothesis that ScvO₂ does not reliably predict SvO₂ in sepsis. Additionally we looked at the influence of the source (splanchnic or non-splanchnic) of sepsis on this relationship.     

Central venous oxygen saturation in septic shock - a marker of cardiac output,microvascular shunting and/or dysoxia?

Shock therapy aims at increasing central venous oxygen saturation (ScvO₂), which is a marker of inadequate oxygen delivery. In this issue of Critical Care, Textoris and colleagues challenge this notion by reporting that high levels of ScvO₂ are associated with mortality in patients with septic shock. This is of obvious interest, but as their retrospective design has inherent limitations, the association should be confirmed in a prospective, multicenter study with protocolized ScvO₂ measurements and detailed registration of potentially confounding factors.     

Near-infrared spectroscopy during stagnant ischemia estimates central venous oxygen saturation and mixed venous oxygen saturation discrepancy in patients with severe left heart failure and additional sepsis/septic shock

Introduction

Discrepancies of 5-24% between superior vena cava oxygen saturation (ScvO₂) and mixed venous oxygen saturation (SvO₂) have been reported in patients with severe heart failure. Thenar muscle tissue oxygenation (StO₂) measured with near-infrared spectroscopy (NIRS) during arterial occlusion testing decreases slower in sepsis/septic shock patients (lower StO₂ deoxygenation rate). The StO₂ deoxygenation rate is influenced by dobutamine. The aim of this study was to determine the relationship between the StO₂ deoxygenation rate and the ScvO₂-SvO₂ discrepancy in patients with severe left heart failure and additional sepsis/septic shock treated with or without dobutamine.

Methods

Fifty-two patients with severe left heart failure due to primary heart disease with additional severe sepsis/septic shock were included. SvO₂ and ScvO₂ were compared to the thenar muscle StO₂ before and during arterial occlusion.

Results

SvO₂ correlated significantly with ScvO₂ (Pearson correlation 0.659, P = 0.001), however, Bland Altman analysis showed a clinically important difference between both variables (ScvO₂-SvO₂ mean 72 ± 8%, ScvO₂-SvO₂ difference 9.4 ± 7.5%). The ScvO₂-SvO₂ difference correlated with plasma lactate (Pearson correlation 0.400, P = 0.003) and the StO₂ deoxygenation rate (Pearson correlation 0.651, P = 0.001). In the group of patients treated with dobutamine, the ScvO₂-SvO₂ difference correlated with plasma lactate (Pearson correlation 0.389, P = 0.011) and the StO₂ deoxygenation rate (Pearson correlation 0.777, P = 0.0001).

Conclusions

In patients with severe heart failure with additional severe sepsis/septic shock the ScvO₂-SvO₂ discrepancy presents a clinical problem. In these patients the skeletal muscle StO₂ deoxygenation rate is inversely proportional to the difference between ScvO₂ and SvO₂; dobutamine does not influence this relationship. When using ScvO₂ as a treatment goal, the NIRS measurement may prove to be a useful non-invasive diagnostic test to uncover patients with a normal ScvO₂ but potentially an abnormally low SvO₂.

Trial Registration

{"type":"clinical-trial","attrs":{"text":"NCT00384644","term_id":"NCT00384644"}}NCT00384644 ClinicalTrials.Gov.     

Thenar oxygen saturation measured by near infrared spectroscopy as a noninvasive predictor of low central venous oxygen saturation in septic patients

Objective  To validate thenar oxygen saturation (StO₂) measured by near-infrared spectroscopy (NIRS) as a noninvasive estimation of central venous saturation (ScvO₂) in septic patients. Design  Prospective observational study. Setting  A 26-bed medical–surgical intensive care unit at a university-affiliated hospital. Patients  Patients consecutively admitted to the ICU in the early phase of severe sepsis and septic shock, after normalization of blood pressure with fluids and/or vasoactive drugs. Measurements  We recorded demographic data, severity score, hemodynamic data, and blood lactate, as well as ScvO₂, and StO₂ measured simultaneously on inclusion. Patients were divided into two groups according to ScvO₂ values: group A, with ScvO₂ < 70%, and group B, with ScvO₂ ≥ 70%. Results  Forty patients were studied. StO₂ was significantly lower in group A than in group B (74.7 ± 13.0 vs. 83.3 ± 6.2, P 0.018). No differences in age, severity score, hemodynamics, vasoactive drugs, or lactate were found between groups. Simultaneously measured ScvO₂ and StO₂ showed a significant Pearson correlation (r = 0.39, P 0.017). For a StO₂ value of 75%, sensitivity was 0.44, specificity 0.93, positive predictive value 0.92, and negative predictive value 0.52 for detecting ScvO₂ values lower than 70%. Conclusions  StO₂ correlates with ScvO₂ in normotensive patients with severe sepsis or septic shock. We propose a StO₂ cut-off value of 75% as a specific, rapid, noninvasive first step for detecting patients with low ScvO₂ values. Further studies are necessary to analyze the role of noninvasive StO₂ measurement in future resuscitation algorithms. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Incidence of low central venous oxygen saturation during unplanned admissions in a multidisciplinary intensive care unit: an observational study

Introduction  

It has been shown that early central venous oxygen saturation (ScvO₂)-guided optimization of hemodynamics can improve outcome in septic patients. The early ScvO₂ profile of other patient groups is unknown. The aim of this study was to characterize unplanned admissions in a multidisciplinary intensive care unit (ICU) with respect to ScvO₂ and outcome.     

Transfusion of Packed Red Blood Cells is Not Associated with Improved Central Venous Oxygen Saturation or Organ Function in Patients with Septic Shock

Background

The exact role of packed red blood cell (PRBC) transfusion in the setting of early resuscitation in septic shock is unknown.

Study Objective

To evaluate whether PRBC transfusion is associated with improved central venous oxygen saturation (ScvO₂) or organ function in patients with severe sepsis and septic shock receiving early goal-directed therapy (EGDT).

Methods

Retrospective cohort study (n = 93) of patients presenting with severe sepsis or septic shock treated with EGDT.

Results

Thirty-four of 93 patients received at least one PRBC transfusion. The ScvO₂ goal > 70% was achieved in 71.9% of the PRBC group and 66.1% of the no-PRBC group (p = 0.30). There was no difference in the change in Sequential Organ Failure Assessment (SOFA) score within the first 24 h in the PRBC group vs. the no-PRBC group (8.6–8.3 vs. 5.8–5.6, p = 0.85), time to achievement of central venous pressure > 8 mm Hg (732 min vs. 465 min, p = 0.14), or the use of norepinephrine to maintain mean arterial pressure > 65 mm Hg (81.3% vs. 83.8%, p = 0.77).

Conclusions

In this study, the transfusion of PRBC was not associated with improved cellular oxygenation, as demonstrated by a lack of improved achievement of ScvO₂ > 70%. Also, the transfusion of PRBC was not associated with improved organ function or improved achievement of the other goals of EGDT. Further studies are needed to determine the impact of transfusion of PRBC within the context of early resuscitation of patients with septic shock.     

Central venous-to-arterial carbon dioxide difference: an additional target for goal-directed therapy in septic shock?

Objective  To test the hypothesis that, in resuscitated septic shock patients, central venous-to-arterial carbon dioxide difference [P(cv-a)CO₂] may serve as a global index of tissue perfusion when the central venous oxygen saturation (ScvO₂) goal value has already been reached. Design  Prospective observational study. Setting  A 22-bed intensive care unit (ICU). Patients  After early resuscitation in the emergency unit, 50 consecutive septic shock patients with ScvO₂ > 70% were included immediately after their admission into the ICU (T0). Patients were separated in Low P(cv-a)CO₂ group (Low gap; n = 26) and High P(cv-a)CO₂ group (High gap; n = 24) according to a threshold of 6 mmHg at T0. Measurements  Measurements were performed every 6 h over 12 h (T0, T6, T12). Results  At T0, there was a significant difference between Low gap patients and High gap patients for cardiac index (CI) (4.3 ± 1.6 vs. 2.7 ± 0.8 l/min/m2, P < 0.0001) but not for ScvO₂ values (78 ± 5 vs. 75 ± 5%, P = 0.07). From T0 to T12, the clearance of lactate was significantly larger for the Low gap group than for the High gap group (P < 0.05) as well as the decrease of SOFA score at T24 (P < 0.01). At T0, T6 and T12, CI and P(cv-a)CO₂ values were inversely correlated (P < 0.0001). Conclusion  In ICU-resuscitated patients, targeting only ScvO₂ may not be sufficient to guide therapy. When the 70% ScvO₂ goal-value is reached, the presence of a P(cv-a)CO₂ larger than 6 mmHg might be a useful tool to identify patients who still remain inadequately resuscitated. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

The incidence of low venous oxygen saturation on admission to the intensive care unit: a multi-center observational study in The Netherlands

Background  

Low mixed or central venous saturation (S(c)vO₂) can reveal global tissue hypoxia and therefore can predict poor prognosis in critically ill patients. Early goal directed therapy (EGDT), aiming at an ScvO₂ ≥ 70%, has been shown to be a valuable strategy in patients with sepsis or septic shock and is incorporated in the Surviving Sepsis Campaign guidelines.     

The peripheral perfusion index and transcutaneous oxygen challenge test are predictive of mortality in septic patients after resuscitation

Introduction

The peripheral perfusion index (PI) is a noninvasive numerical value of peripheral perfusion, and the transcutaneous oxygen challenge test (OCT) is defined as the degree of transcutaneous partial pressure of oxygen (PtcO₂) response to 1.0 FiO_2. The value of noninvasive monitoring peripheral perfusion to predict outcome remains to be established in septic patients after resuscitation. Moreover, the prognostic value of PI has not been investigated in septic patients.

Methods

Forty-six septic patients, who were receiving PiCCO-Plus cardiac output monitoring, were included in the study group. Twenty stable postoperative patients were studied as a control group. All the patients inspired 1.0 of FiO₂ for 10 minutes during the OCT. Global hemodynamic variables, traditional metabolic variables, PI and OCT related-variables were measured simultaneously at 24 hours after PiCCO catheter insertion. We obtained the 10min-OCT ((PtcO₂ after 10 minutes on inspired 1.0 oxygen) - (baseline PtcO₂)), and the oxygen challenge index ((10min-OCT)/(PaO₂ on inspired 1.0 oxygen - baseline PaO₂)) during the OCT.

Results

The PI was significantly correlated with baseline PtcO₂, 10min-OCT and oxygen challenge index (OCI) in all the patients. The control group had a higher baseline PtcO₂, 10min-OCT and PI than the septic shock group. In the sepsis group, the macro hemodynamic parameters and ScvO₂ showed no differences between survivors and nonsurvivors. The nonsurvivors had a significantly lower PI, 10min-OCT and OCI, and higher arterial lactate level. The PI, 10min-OCT and OCI predicted the ICU mortality with an accuracy that was similar to arterial lactate level. A PI <0.2 and a 10min-OCT <66mmHg were related to poor outcome after resuscitation.

Conclusions

The PI and OCT are predictive of mortality for septic patients after resuscitation. Further investigations are required to determine whether the correction of an impaired level of peripheral perfusion may improve the outcome of septic shock patients.     

In-hospital mortality following treatment with red blood cell transfusion or inotropic therapy during early goal-directed therapy for septic shock: a retrospective propensity-adjusted analysis

Introduction

We sought to investigate whether treatment of subnormal (<70%) central venous oxygen saturation (ScvO₂) with inotropes or red blood cell (RBC) transfusion during early goal-directed therapy (EGDT) for septic shock is independently associated with in-hospital mortality.

Methods

Retrospective analysis of a prospective EGDT patient database drawn from 21 emergency departments with a single standardized EGDT protocol. Patients were included if, during EGDT, they concomitantly achieved a central venous pressure (CVP) of ≥8 mm Hg and a mean arterial pressure (MAP) of ≥65 mm Hg while registering a ScvO₂ < 70%. Treatment propensity scores for either RBC transfusion or inotrope administration were separately determined from independent patient sub-cohorts. Propensity-adjusted logistic regression analyses were conducted to test for associations between treatments and in-hospital mortality.

Results

Of 2,595 EGDT patients, 572 (22.0%) met study inclusion criteria. The overall in-hospital mortality rate was 20.5%. Inotropes or RBC transfusions were administered for an ScvO₂ < 70% to 51.9% of patients. Patients were not statistically more likely to achieve an ScvO₂ of ≥70% if they were treated with RBC transfusion alone (29/59, 49.2%, P = 0.19), inotropic therapy alone (104/226, 46.0%, P = 0.15) or both RBC and inotropic therapy (7/12, 58.3%, P = 0.23) as compared to no therapy (108/275, 39.3%). Following adjustment for treatment propensity score, RBC transfusion was associated with a decreased adjusted odds ratio (aOR) of in-hospital mortality among patients with hemoglobin values less than 10 g/dL (aOR 0.42, 95% CI 0.18 to 0.97, P = 0.04) while inotropic therapy was not associated with in-hospital mortality among patients with hemoglobin values of 10 g/dL or greater (aOR 1.16, 95% CI 0.69 to 1.96, P = 0.57).

Conclusions

Among patients with septic shock treated with EGDT in the setting of subnormal ScvO₂ values despite meeting CVP and MAP target goals, treatment with RBC transfusion may be independently associated with decreased in-hospital mortality.     

Prospective evaluation of regional oxygen saturation to estimate central venous saturation in sepsis

Current treatment guidelines for sepsis claim an early goal-directed hemodynamic optimization including fluid resuscitation, use of vasopressors and inotropic agents. We investigated the correlation between the prominent treatment goal central venous saturation (ScvO₂) and the frontal and the thenar regional oxygen saturation (rSO₂) measured by near infrared spectroscopy. Secondary, we examined the value of ScvO₂, lactate levels and rSO₂ as surrogate markers of an impaired tissue oxygenation for outcome prediction in sepsis. This prospective, observational study was performed at the surgical intensive care unit of the University Hospital Giessen. A total of 50 patients with sepsis, severe sepsis or septic shock were included. ScvO₂, rSO₂ and lactate were measured at sepsis diagnosis (baseline), 24 and 48 h, thereafter. We investigated the predictive value of frontal and thenar rSO₂ for a decreased SvcO₂ under 70 %. For survivor and non-survivors ScvO₂, rSO₂ and lactate were analysed. Patients with ScvO₂ >70 % showed a trend to higher levels of fontal rSO₂ (62.81 ± 8.06 vs. 53.54 ± 15.48; p = 0.058). ROC-analysis revealed a minor prediction of a decreased ScvO₂ by frontal rSO₂ levels at baseline (AUC = 0.687; 95 % CI 0.511–0.863; p = 0.047). Combined measurements of lactate and ScvO2 showed significantly elevated mortality for patients with ScvO2 ≥70 % and lactate levels ≥2.5 mmol/l (log rank test p = 0.004). In the group with ScvO₂ <70 % and lactate levels <2.5 mmol/l no patients died during the observation period. Frontal rSO₂ correlates with ScvO₂ but both frontal and thenar rSO2 do not exactly discriminate between patients with high or low ScvO2 in sepsis. The combination of elevated lactate >2.5 mmol/l and ScvO₂ >70 % is highly associated with poor outcome in ICU patients with sepsis, severe sepsis and septic shock.     

Prognostic implications of tissue oxygen saturation in human septic shock

Purpose  

To analyze the prognostic value of tissue oxygen saturation (StO₂) in septic shock patients with restored mean arterial pressure (MAP).     

Mixed venous oxygen saturation cannot be estimated by central venous oxygen saturation in septic shock

Objective Central venous oxygen saturation (ScvO₂) in initial resuscitation is included in the Surviving Sepsis Campaign guidelines. ScvO₂ monitoring has also been suggested to be comparable to mixed venous oxygen saturation (SvO₂) for clinical purposes. The aim of our study was to assess the correlation and agreement of ScvO₂ and SvO₂ and compare ScvO₂–SvO₂ difference to lactate, oxygen-derived and hemodynamic parameters in early septic shock in ICU after initial resuscitation.Design and setting Prospective clinical study with 16 patients with septic shock at two university hospital ICUs. A dose of norepinephrine over 0.1 μg/kg/min was required for inclusion.Measurements and results Five paired ScvO₂ and SvO₂ samples at 6-h intervals, altogether 72 samples, were collected during 24 h. The mean SvO₂ was below the mean ScvO₂ at all time points. Bias of difference was 4.2% and 95% limits of agreement ranged from –8.1% to 16.5%. The difference correlated significantly to CI and DO₂.Conclusions The difference between paired ScvO₂ and SvO₂ varies highly. Therefore, SvO₂ may not be estimated on the basis of ScvO₂ in treatment of septic shock after resuscitation period in ICU.Electronic supplementary material The electronic reference of this article is . The online full-text version of this article includes electronic supplementary material. This material is available to authorised users and can be accessed by means of the ESM button beneath the abstract or in the structured full-text article. To cite or link to this article you can use the above reference.     

Association of left ventricular longitudinal strain with central venous oxygen saturation and serum lactate in patients with early severe sepsis and septic shock

IntroductionIn septic shock, assessment of cardiac function often relies on invasive central venous oxygen saturation (ScvO₂). Ventricular strain is a non-invasive method of assessing ventricular wall deformation and may be a sensitive marker of heart function. We hypothesized that it may have a relationship with ScvO₂ and lactate.MethodsWe prospectively performed transthoracic echocardiography in patients with severe sepsis or septic shock and measured (1) left ventricular longitudinal strain from a four-chamber view and (2) ScvO₂. We excluded patients for whom image quality was inadequate or for whom ScvO₂ values were unobtainable. We determined the association between strain and ScvO₂ with logistic and linear regression, using covariates of mean arterial pressure, central venous pressure, and vasopressor dose. We determined the association between strain and lactate. We considered strain greater than −17 % as abnormal and strain greater than −10 % as severely abnormal.ResultsWe studied 89 patients, 68 of whom had interpretable images. Of these patients, 42 had measurable ScvO₂. Sixty percent of patients had abnormal strain, and 16 % had severely abnormal strain. Strain is associated with low ScvO₂ (linear coefficient −1.05, p =0.006; odds ratio 1.23 for ScvO₂ <60 %, p =0.016). Patients with severely abnormal strain had significantly lower ScvO₂ (56.1 % vs. 67.5 %, p <0.01) and higher lactate (2.7 vs. 1.9 mmol/dl, p =0.04) than those who did not. Strain was significantly different between patients, based on a threshold ScvO₂ of 60 % (−13.7 % vs. -17.2 %, p =0.01) but not at 70 % (−15.0 % vs. −18.2 %, p =0.08).ConclusionsLeft ventricular strain is associated with low ScvO₂ and hyperlactatemia. It may be a non-invasive surrogate for adequacy of oxygen delivery during early severe sepsis or septic shock.     

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. Complete hemodynamic and gas measurements were obtained at baseline, and at each dose of dobutamine.

Results

Dobutamine induced a significant dose-dependent increase of CI from 0 to 15 μg/kg/min (P < 0.001). Oxygen consumption (VO₂) and VCO₂ were progressively increased by dobutamine. These increases were more marked between 10 and 15 μg/kg/min (8.3 and 8.6 %, respectively) than between the lower doses. ?PCO₂ and oxygen extraction (EO₂) significantly decreased between 0 (8.0 ± 2.0 mmHg and 43.8 ± 13.4 %, respectively) and 10 μg/kg/min of dobutamine (4.2 ± 1.6 mmHg and 28.9 ± 7.9 %, respectively), but remained unchanged from 10 to 15 μg/kg/min (5.4 ± 2.4 mmHg and 29.5 ± 8.2 %, respectively). The central venous oxygen saturation significantly (ScvO₂) increased from 0 to 10 μg/kg/min and remained unchanged from 10 to 15 μg/kg/min. Time courses of ?PCO₂, ScvO₂, and EO₂ were linked therefore to the biphasic changes of VO₂ and VCO₂.

Conclusion

?PCO₂ is a good indicator of the change of VCO₂ induced by dobutamine. Measurement of ?PCO₂, along with ScvO₂ and EO₂, may be presented as a useful tool to assess the adequacy of oxygen supply versus metabolic and oxygen demand.     

Bedside monitoring of patients with shock using a portable spatially-resolved near-infrared spectroscopy

Clinical monitoring of shock mainly depends on blood-oxygen-indices obtained from invasive blood sample tests. The central internal jugular central vein oxygenation level (ScvO₂) has been considered as a gold standard indicator for shock prediction. We developed a noninvasive spatially-resolved near-infrared spectroscopy (SR-NIRS) to measure tissue blood oxygen saturation (StO₂) surrounding the region of taking blood sample for the ScvO₂ test in 25 patients with shock. StO₂ values were found to be highly correlated (r = 0.84, p < 0.001) with ScvO₂ levels and the concordance coefficient of 0.80 is high. The results suggest the potential of noninvasive SR-NIRS for bedside shock monitoring.OCIS codes: (170.1470) Blood or tissue constituent monitoring, (300.0300) Spectroscopy     

Bench-to-bedside review: The initial hemodynamic resuscitation of the septic patient according to Surviving Sepsis Campaign guidelines – does one size fit all?

The Surviving Sepsis Campaign guidelines for the management of severe sepsis and septic shock recommend that the initial hemodynamic resuscitation be done according to the protocol used by Rivers and colleagues in their well-known early goal-directed therapy (EGDT) study. However, it may well be that their patients were much sicker on admission than many other septic patients. Compared with other populations of septic patients, the patients of Rivers and colleagues had a higher incidence of severe comorbidities, a more severe hemodynamic status on admission (excessively low central venous oxygen saturation [ScvO₂], low central venous pressure [CVP], and high lactate), and higher mortality rates. Therefore, it may well be that these patients arrived to the hospital in late untreated hypovolemic sepsis, which may have been due, in part at least, to low socioeconomic status and reduced access to health care. The EGDT protocol uses target values for CVP and ScvO₂ to guide hemodynamic management. However, filling pressures do not reliably predict the response to fluid administration, while the ScvO₂ of septic patients is characteristically high due to decreased oxygen extraction. For all these reasons, it seems that the hemodynamic component of the Surviving Sepsis Campaign guidelines cannot be applied to all septic patients, particularly those who develop sepsis during their hospital stay.     

Low and “supranormal” central venous oxygen saturation and markers of tissue hypoxia in cardiac surgery patients: a prospective observational study

Purpose  

To characterize incidence of low, normal and “supranormal” central venous oxygen saturation (ScvO₂) and the relation to markers of tissue hypoxia, course and outcome in cardiac surgery patients.