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OBJECTIVE: To investigate maternal and neonatal outcomes after a delivery in France in 2019, according to hospital characteristics and the impact of distance and time of travel on mother and newborn. METHODS: All parturients above 18 years of age who delivered in 2019 and were identified in the French health insurance database were included, with their newborns, in this retrospective cohort study. Main outcome measures were Severe Maternal Morbidity score and the Neonatal Adverse Outcome Indicator (NAOI). RESULTS: Among the 733 052 pregnancies included, 10 829 presented a severe maternal morbidity (1.48%) and 77 237 had a neonatal adverse outcome (10.4%). Factors associated with an unfavorable maternal or neonatal outcome were Obstetric Comorbidity Index, primiparity, and cesarean or instrumental delivery. Prematurity was associated with less severe maternal morbidity but more neonatal adverse outcomes. Time of travel above 30 min was associated with a higher NAOI rate. CONCLUSIONS: Results suggest the efficiency of regionalization of perinatal care in France, although a difference in both outcomes persists according to unit volume, suggesting the need for a further step in concentrating perinatal care. Perinatal care organization should focus on mapping the territory with high-level, high-volume maternity throughout the territory; this suggests closing down high-volume units and improving low-volume ones to maintain coherent mapping.
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Mães , Assistência Perinatal , Criança , Recém-Nascido , Gravidez , Humanos , Feminino , Estudos Retrospectivos , Parto Obstétrico/métodos , França/epidemiologiaRESUMO
BACKGROUND: Hip arthroplasty is a frequently performed procedure in orthopedic surgery, carried out in almost all health structures for two main issues: fracture and coxarthrosis. Even if volume-outcome relationship appeared associated in many surgeries recently, data provided are not sufficient to set surgical thresholds neither than closing down low-volumes centers. QUESTION: With this study, we wanted to identify surgical, health care-related and territorial factors influencing patient' mortality and readmission after a HA for a femoral fracture in 2018 in France. PATIENTS AND METHODS: Data were anonymously collected from French nationwide administrative databases. All patients who underwent a hip arthroplasty for a femoral fracture through 2018 were included. Patient outcome was 90-day mortality and 90-day readmission rate after surgery. RESULTS: Of the 36,252 patients that underwent a HA for fracture in France in 2018, 0.7% died within 90-day year and 1.2% were readmitted. Male and Charlson comorbidity index were associated with a higher 90-day mortality and readmission rate in multivariate analysis. High volume was associated with a lower mortality rate. Neither time of travel nor distance upon health facility were associated with mortality nor with readmission rate in the analysis. CONCLUSION: Even if volume appears to be associated with lower mortality rate even for longer distance and time of travel, the persistence of exogenous factors not documented in the French databases suggests that regionalization of hip arthroplasty should be organized with caution. CLINICAL RELEVANCE: As volume-outcome relationship must be interpreted with caution, policy makers should not regionalize such surgery without further investigation.
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Artroplastia de Quadril , Fraturas do Fêmur , Fraturas do Quadril , Humanos , Masculino , Fatores de Risco , Hospitais , Atenção à Saúde , Fêmur/cirurgia , Fraturas do Fêmur/cirurgia , Fraturas do Quadril/cirurgia , Estudos RetrospectivosRESUMO
This paper describes the development and implementation of an anesthesia data warehouse in the Lille University Hospital. We share the lessons learned from a ten-year project and provide guidance for the implementation of such a project. Our clinical data warehouse is mainly fed with data collected by the anesthesia information management system and hospital discharge reports. The data warehouse stores historical and accurate data with an accuracy level of the day for administrative data, and of the second for monitoring data. Datamarts complete the architecture and provide secondary computed data and indicators, in order to execute queries faster and easily. Between 2010 and 2021, 636 784 anesthesia records were integrated for 353 152 patients. We reported the main concerns and barriers during the development of this project and we provided 8 tips to handle them. We have implemented our data warehouse into the OMOP common data model as a complementary downstream data model. The next step of the project will be to disseminate the use of the OMOP data model for anesthesia and critical care, and drive the trend towards federated learning to enhance collaborations and multicenter studies.
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Anestesia , Data Warehousing , HumanosRESUMO
INTRODUCTION: Many recent studies have investigated the hospital volume-outcome relationship in surgery. In some cases, the results have prompted the centralization of surgical activity. However, the methodologies and interpretations differ markedly from one study to another. The objective of the present scoping review was to describe the various features used to assess the volume-outcome relationship: the analyzed datasets, study population, outcome, covariates, confounders, volume modalities, and statistical methods. METHODS AND ANALYSIS: The review was conducted according to a study protocol published in BMJ Open in 2020. Two authors (both of whom had helped to design the study protocol) screened publications independently according to the title, the abstract and then the full text. To ensure exhaustivity, all the papers included by each reviewer went through to the next step. INTERPRETATION: The 403 included studies covered 90 types of surgery, 61 types of outcome, and 72 covariates or potential confounders. 191 (47.5%) studies focussed on oncological surgery and 37.8% focussed visceral or digestive tract surgery. Overall, 86.6% of the studies found a statistically significant volume-outcome relationship, although the findings differed from one type of surgery to another. Furthermore, the types of outcome and the covariates were highly diverse. The majority of studies were performed in Western countries, and oncological and visceral surgical procedures were over-represented; this might limit the generalizability and comparability of the studies' results.
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Procedimentos Cirúrgicos do Sistema Digestório , Hospitais , Atenção à Saúde , HumanosRESUMO
The purpose of the study was to evaluate the behavior of the venous-to-arterial CO2 tension difference (ΔPCO2) over the arterial-to-venous oxygen content difference (ΔO2) ratio (ΔPCO2/ΔO2) and the difference between venous-to-arterial CO2 content calculated with the Douglas' equation (ΔCCO2D) over ΔO2 ratio (ΔCCO2D/ΔO2) and their abilities to reflect the occurrence of anaerobic metabolism in two experimental models of tissue hypoxia: ischemic hypoxia (IH) and hypoxic hypoxia (HH). We also aimed to assess the influence of metabolic acidosis and Haldane effects on the PCO2/CO2 content relationship. In a vascularly isolated, innervated dog hindlimb perfused with a pump-membrane oxygenator system, the oxygen delivery (DO2) was lowered in a stepwise manner to decrease it beyond critical DO2 (DO2crit) by lowering either arterial PO2 (HH-model) or flow (IH-model). Twelve anesthetized and mechanically ventilated dogs were studied, 6 in each model. Limb DO2, oxygen consumption ([Formula: see text]), ΔPCO2/ΔO2, and ΔCCO2D/ΔO2 were obtained every 15 min. Beyond DO2crit, [Formula: see text] decreased, indicating dysoxia. ΔPCO2/ΔO2, and ΔCCO2D/ΔO2 increased significantly only after reaching DO2crit in both models. At DO2crit, ΔPCO2/ΔO2 was significantly higher in the HH-model than in the IH-model (1.82 ± 0.09 vs. 1.39 ± 0.06, p = 0.002). At DO2crit, ΔCCO2D/ΔO2 was not significantly different between the two groups (0.87 ± 0.05 for IH vs. 1.01 ± 0.06 for HH, p = 0.09). Below DO2crit, we observed a discrepancy between the behavior of the two indices. In both models, ΔPCO2/ΔO2 continued to increase significantly (higher in the HH-model), whereas ΔCCO2D/ΔO2 tended to decrease to become not significantly different from its baseline in the IH-model. Metabolic acidosis significantly influenced the PCO2/CO2 content relationship, but not the Haldane effect. ΔPCO2/ΔO2 was able to depict the occurrence of anaerobic metabolism in both tissue hypoxia models. However, at very low DO2 values, ΔPCO2/ΔO2 did not only reflect the ongoing anaerobic metabolism; it was confounded by the effects of metabolic acidosis on the CO2-hemoglobin dissociation curve, and then it should be interpreted with caution.
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Dióxido de Carbono/sangue , Hipóxia Celular/fisiologia , Hipóxia/sangue , Isquemia/sangue , Oxigênio/sangue , Acidose/sangue , Anaerobiose/fisiologia , Animais , Artérias , Gasometria , Cães , Membro Posterior/irrigação sanguínea , Concentração de Íons de Hidrogênio , Modelos Teóricos , Fluxo Sanguíneo Regional , VeiasRESUMO
BACKGROUND: Antimicrobial resistance (AMR) is a serious threat to humanity. This paper describes the French efforts made since 2001 and presents data on antimicrobial consumption (AC) and AMR. METHODS: We gathered all data on AC and AMR recorded since 2001 from different national agencies, transferred on a regular basis to standardized European data on AC and resistance in both humans and animals. RESULTS: After a large information campaign implemented in France from 2001 to 2005 in humans, AC in the community decreased significantly (18% to 34% according to the calculation method used). It remained at the same level from 2005 to 2010 and increased again from 2010 to 2018 (8%). Contrasting results were observed for AMR. The resistance of Staphylococcus aureus decreased significantly. For gram-negative bacilli, the results were variable according to the microorganism. The resistance of Enterobacteriaceae to third-generation cephalosporins increased, remaining moderate for Escherichia coli (12% in 2017) but reaching 35% in the same year for Klebsiella pneumoniae. Resistance to carbapenems in those 2 microorganisms remained below 1%. Both global AC and resistance to most antibiotics decreased significantly in animals. CONCLUSIONS: Antibiotic consumption decreased significantly in France after a large public campaign from 2001 to 2005, but this positive effect was temporary. The effect on AMR varied according to the specific microorganism: The effect was very impressive for gram-positive cocci, variable for gram-negative bacilli, and moderate for E. coli, but that for K. pneumoniae was of concern. The consumption of and resistance to antibiotics decreased significantly in animals.
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BACKGROUND: Students' choice of medical specialties has evolved throughout year, with a growing interest in quality of life and in technological specialties. We investigated the repartition of such choices in the world and its influencing factors with a focus on the gender's influence, for helping policy-makers to deal with medical shortage and territorial to specialty disconnect. METHODS: A systematic search was conducted on MEDLINE and Scopus from January 2010 to January 2020. Data extraction and analysis followed JBI and PRISMA recommendations. The selected articles had to focus on medical students, detail their choice of specialty, and look for factors influencing their choice. Articles were excluded if they only assessed the attractiveness of a specialty, or evaluated a public policy. This review was registered on PROSPERO, CRD 42020169227. FINDINGS: 751 studies were screened, and fifty-four were included. Surgery and internal medicine were the most wanted specialties, both in occidental and non-occidental countries. The main factors influencing the choice of specialty were lifestyle, work-life balance and discipline interest, with variation across different countries. Gender clearly affected this choice with 63.7% of men willing radiology and 14.7% of men in obstetrics and gynecology. INTERPRETATION: Influential factors vary with specialty and are affected by the country of residence. Gender has a great impact in students' willingness to work in specific specialties. Policymakers should adapt their appealing strategies according to the country and the medical discipline concerned. FUNDING: The authors have no support or funding to report.
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INTRODUCTION: Even if a positive volume-outcome correlation in surgery is mostly admitted in many surgical fields, the various ways to assess this relationship make it difficult for researchers and policymakers to use it. Our aim is therefore to provide an overview of the way hospital volume-outcome relationship was assessed. Through this overview, our goal is to identify potential gaps in the assessment of this relationship, to help researchers who want to pursue work in this field and, ultimately, to help policy makers interpret such analyses. METHODS AND ANALYSIS: This review will be conducted using the six stages of the scoping review method: identifying the research question, searching for relevant studies, selecting studies, data extraction, collating, summarising and reporting the results and concluding. This review will address all the key questions used to assess the volume-outcome relationship in surgery.Primary research papers investigating the hospital volume-outcome relationship from 2009 will be included. Studies only looking at surgeons' volume-outcome relationship or studies were the volume variable is not individualisable will be excluded.Both MEDLINE and Scopus will be searched along with grey literature. Two researchers will perform all the stages of the review: screen the titles and abstracts, review the full text of selected articles to determine final inclusions and extract the data. The results will be summarised quantitatively using numerical counts. ETHICAL CONSIDERATIONS AND DISSEMINATION: Reviews of published articles are considered secondary analysis and do not need ethical approval. The findings will be disseminated through multiple channels like conferences and peer-reviewed journals.
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Hospitais , Projetos de Pesquisa , Procedimentos Cirúrgicos Operatórios , Hospitais com Alto Volume de Atendimentos , Humanos , Revisão por Pares , Literatura de Revisão como AssuntoRESUMO
OBJECTIVES: RBC transfusions can increase oxygen availability to the tissues, but studies have provided conflicting results. The objectives of this study were, therefore, to evaluate, using systematic review and meta-analysis, the effects of transfusion on hemodynamic/oxygenation variables in patients without acute bleeding. DATA SOURCES: PubMed, Scopus, Cochrane Database of Systematic Reviews, and Embase from inception until June 30, 2019. STUDY SELECTION: All articles that reported values of prespecified hemodynamic or oxygenation variables before and after RBC transfusion. DATA EXTRACTION: Publication year, number of patients, number of transfusions and the type of population studied, hemodynamic and oxygenation data (heart rate, cardiac index, mixed venous oxygen saturation or central venous oxygen saturation, oxygen delivery index, oxygen consumption index, oxygen extraction ratio, arteriovenous oxygen difference and arterial blood lactate) before and after transfusion. We performed a meta-analysis for each variable for which there were sufficient data to estimate mean differences. We also performed subgroup analyses comparing septic with nonseptic patients. DATA SYNTHESIS: We retrieved 6,420 studies; 33 met the inclusion criteria, 14 of which were in patients with sepsis. In the meta-analysis, the estimated mean differences and 95% CIs comparing the periods before and after transfusion were -0.0 L/min/m (-0.1 to 0.1 L/min/m) (p = 0.86) for cardiac index; -1.8 beats/min (-3.7 to 0.1 beats/min) (p = 0.06) for heart rate; 96.8 mL/min/m (71.1-122.5 mL/min/m) (p < 0.01) for oxygen delivery index; 2.9% (2.2-3.5%) (p < 0.01) for mixed venous oxygen saturation or central venous oxygen saturation; -3.7% (-4.4% to -3.0%) (p < 0.01) for oxygen extraction ratio; and 4.9 mL/min/m (0.9-9.0 mL/min/m) (p = 0.02) for oxygen consumption index. The estimated mean difference for oxygen consumption index in the patients with sepsis was 8.4 mL/min/m (2.3-14.5 mL/min/m; p = 0.01). CONCLUSIONS: Transfusion was not associated with a decrease in mean cardiac output or mean heart rate. The increase in mean oxygen delivery following transfusion was associated with an increase in mean oxygen consumption after transfusion, especially in patients with sepsis.
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Transfusão de Eritrócitos , Hemodinâmica/fisiologia , Oxigênio/sangue , HumanosAssuntos
Saúde Global , Política , Saúde Pública , Educação Profissional em Saúde Pública , França , Humanos , EstudantesRESUMO
The physiology of venous and tissue CO2 monitoring has a long and well-established physiological background, leading to the technological development of different tissue capnometric devices, such as transcutaneous capnometry monitoring (TCM). To outline briefly, measuring transcutaneous PCO2 (tcPCO2) depends on at least three main phenomena: (I) the production of CO2 by tissues (VCO2), (II) the removal of CO2 from the tissues by perfusion (wash-out phenomenon), and (III) the reference value of CO2 at tissue inlet represented by arterial CO2 content (approximated by arterial PCO2, or artPCO2). For this reason, there are, at present, roughly two clinical uses for tcPCO2 measurement: a respiratory approach where tcPCO2 is likely to estimate and non-invasively track artPCO2; and a hemodynamic under-estimate use where tcPCO2 can reflect tissue perfusion, summarized by a so-called "tc-art PCO2 gap". Recent research shows that these two uses are not incompatible and could be combined. The spectrum of indications and validation studies in ICUs is summarized in this review to give a survey of the potential applications of TCM in critically ill patients, focusing mainly on its potential (micro)circulatory monitoring contribution. We strongly believe that the greatest benefit of measuring tcPCO2 is not to only to estimate artPCO2, but also to quantify the gap between these two values, which can then help clinicians continuously and noninvasively assess both respiratory and hemodynamic failures in critically ill patients.
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BACKGROUND: Rapid identification and treatment of tissue hypoxia reaching anaerobiosis (dysoxia) may reduce organ failure and the occurrence of major postoperative complications (MPC) after cardiac surgery. The predictive ability of PCO2-based dysoxia biomarkers, central venous-to-arterial PCO2 difference (ΔPCO2) and ΔPCO2 to arteriovenous oxygen content difference ratio, is poorly studied in this setting. OBJECTIVES: We evaluated the ability of PCO2-based tissue dysoxia biomarkers, blood lactate concentration and central venous oxygen saturation measured 2âh after admission to the ICU as predictors of MPC. DESIGN: A prospective, observational cohort study. SETTING: Single-centre, academic hospital cardiovascular ICU. PATIENTS: We included adult patients undergoing cardiac surgery with cardiopulmonary bypass and measured dysoxia biomarkers at ICU admission, and after 2, 6 and 24âh. MAIN OUTCOME MEASURES: The primary endpoint was MPC, a composite of cardiac and noncardiac MPC evaluated in the 48âh following surgery. After univariate analysis of MPC covariates including dysoxia biomarkers measured at 2âh, multivariate logistic regression analyses were performed to identify the association of these biomarkers with MPC for confounders. Areas under the receiver operating characteristic curves were determined for biomarkers which remained independently associated with MPC. RESULTS: MPC occurred in 56.5% of the 308 patients analysed. ΔPCO2, blood lactate concentration and central venous oxygen saturation measured at 2âh, but not ΔPCO2 to arteriovenous oxygen content difference ratio, were significantly associated with MPC. However, only ΔPCO2 was independently associated with MPC after multivariate analysis. The areas under the receiver operating characteristic curves of ΔPCO2 measured at 2âh for MPC prediction was 0.64 (95% CI 0.57 to 0.70, Pâ<â0.001). CONCLUSION: After cardiac surgery with cardiopulmonary bypass, ΔPCO2 measured 2âh after ICU admission was the only dysoxia biomarker independently associated with MPC, but with limited performance. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03107572.
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Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ponte Cardiopulmonar/efeitos adversos , Hipóxia/sangue , Complicações Pós-Operatórias/diagnóstico , Idoso , Biomarcadores/sangue , Gasometria , Dióxido de Carbono/sangue , Feminino , Humanos , Hipóxia/etiologia , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Complicações Pós-Operatórias/etiologia , Prognóstico , Estudos Prospectivos , Medição de Risco , Resultado do TratamentoAssuntos
Febre Amarela , Guiana Francesa , Humanos , Estudos Retrospectivos , Vacinação , Cobertura VacinalRESUMO
In critically ill patients, tissue hypoperfusion is an important cause leading to multi-organ dysfunction and death, and it cannot always be detected by measuring standard global hemodynamic and oxygen-derived parameters. Gastric intramucosal partial pressure of carbon dioxide (PCO2) as measured by gastric tonometry has been recognized to be of clinical value as a prognostic factor, in assessing the effects of particular therapeutic interventions, and as an end-point of resuscitation. However, this technique has several limitations that have hampered its implementation in clinical practice. The sublingual tissue bed has been shown to be damaged in models of shock, and microcirculatory changes in this area may indicate imminent changes in other important organs. The measurement of sublingual mucosal PCO2 (PslCO2) by sublingual capnography is technically simple, noninvasive and gives near instantaneous results. Clinical studies have established that high PslCO2 values and, more especially, high PslCO2 gap (PslCO2 - arterial PCO2) values are correlated with impaired microcirculatory blood flow and a poor outcome in critically ill patients. Sublingual capnography seems to be the ideal noninvasive monitoring tool to evaluate the severity of shock states and the adequacy of tissue perfusion. However, clinical studies are needed to determine the clinical utility of PslCO2 gap monitoring as end-point target to guide resuscitation in critically ill patients.
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Monitorização Transcutânea dos Gases Sanguíneos/métodos , Mucosa/irrigação sanguínea , Fluxo Sanguíneo Regional , Pele/irrigação sanguínea , Humanos , ManometriaAssuntos
Surtos de Doenças , Microcefalia/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Doenças Virais Sexualmente Transmissíveis/epidemiologia , Infecção por Zika virus/epidemiologia , Animais , Feminino , França , Guiana Francesa/epidemiologia , Guadalupe/epidemiologia , Síndrome de Guillain-Barré/epidemiologia , Síndrome de Guillain-Barré/prevenção & controle , Síndrome de Guillain-Barré/virologia , Humanos , Insetos Vetores , Martinica/epidemiologia , Microcefalia/prevenção & controle , Microcefalia/virologia , Controle de Mosquitos/métodos , Polinésia/epidemiologia , Gravidez , Complicações Infecciosas na Gravidez/prevenção & controle , Saúde Pública , Doenças Virais Sexualmente Transmissíveis/prevenção & controle , Zika virus , Infecção por Zika virus/prevenção & controleRESUMO
On Friday November 13th at 9:20 pm, three kamikaze bombs went off around the Stade de France a stadium in Saint-Denis just outside Paris, 4 different shootings took place and bombings in Paris and hundreds of people were held hostage in a theater.This multi-site terrorist attack was the first of this magnitude in France. Drawing the lessons of these attacks and those which occurred in other countries from a health perspective is essential to continuously adapt and improve the French response to possible future attacks. Several issues would need to be further explored: Management of uncertainties: When to trigger the plans: after the 1st attack, the 2nd? When do attacks end and when to release mobilized resources? Management of victims: How to ensure that all victims are secured or taken care of? How to provide assistance when attacks are ongoing? Management of teams: Proper follow-up of persons involved in the response: health professionals, police and firemen, emergency call centers but also civil servants within administration that contributed to the response. Communication: Reactivity of all is a key element to secure appropriate resource is mobilized for the response. All actors have to be able to communicate quickly in a secured way.
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Atenção à Saúde/organização & administração , Serviços Médicos de Emergência/métodos , Terrorismo/tendências , Atenção à Saúde/métodos , Planejamento em Desastres/organização & administração , Planejamento em Desastres/normas , Serviços Médicos de Emergência/organização & administração , Serviços Médicos de Emergência/estatística & dados numéricos , Explosões/estatística & dados numéricos , Humanos , Paris , Terrorismo/psicologia , Terrorismo/estatística & dados numéricosRESUMO
The mixed venous-to-arterial carbon dioxide (CO2) tension difference [P (v-a) CO2] is the difference between carbon dioxide tension (PCO2) in mixed venous blood (sampled from a pulmonary artery catheter) and the PCO2 in arterial blood. P (v-a) CO2 depends on the cardiac output and the global CO2 production, and on the complex relationship between PCO2 and CO2 content. Experimental and clinical studies support the evidence that P (v-a) CO2 cannot serve as an indicator of tissue hypoxia, and should be regarded as an indicator of the adequacy of venous blood to wash out the total CO2 generated by the peripheral tissues. P (v-a) CO2 can be replaced by the central venous-to-arterial CO2 difference (ΔPCO2), which is calculated from simultaneous sampling of central venous blood from a central vein catheter and arterial blood and, therefore, more easy to obtain at the bedside. Determining the ΔPCO2 during the resuscitation of septic shock patients might be useful when deciding when to continue resuscitation despite a central venous oxygen saturation (ScvO2) > 70% associated with elevated blood lactate levels. Because high blood lactate levels is not a discriminatory factor in determining the source of that stress, an increased ΔPCO2 (> 6 mmHg) could be used to identify patients who still remain inadequately resuscitated. Monitoring the ΔPCO2 from the beginning of the reanimation of septic shock patients might be a valuable means to evaluate the adequacy of cardiac output in tissue perfusion and, thus, guiding the therapy. In this respect, it can aid to titrate inotropes to adjust oxygen delivery to CO2 production, or to choose between hemoglobin correction or fluid/inotrope infusion in patients with a too low ScvO2 related to metabolic demand. The combination of P (v-a) CO2 or ΔPCO2 with oxygen-derived parameters through the calculation of the P (v-a) CO2 or ΔPCO2/arteriovenous oxygen content difference ratio can detect the presence of global anaerobic metabolism.
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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. Fluid-responders were defined as a ≥15 % increase in cardiac index. Areas under the receiver operating characteristic curves (AUC) were determined for these variables. RESULTS: Fifty-one patients were fluid-responders (52 %). DO2 increased significantly (31 ± 12 %) in these patients. An increase in VO2 ≥ 15 % ("VO2-responders") concurrently occurred in 57 % of the 51 fluid-responders (45 ± 16 %). Compared with VO2-non-responders, VO2-responders were characterized by higher lactate levels and higher ∆ContCO2/∆ContO2 and ∆PCO2/∆ContO2 ratios. At baseline, lactate predicted a fluid-induced increase in VO2 ≥ 15 % with AUC of 0.745. Baseline ∆ContCO2/∆ContO2 and ∆PCO2/∆ContO2 ratios predicted an increase of VO2 ≥ 15 % with AUCs of 0.965 and 0.962, respectively. Baseline ScvO2 was not able to predict an increase of VO2 ≥ 15 % (AUC = 0.624). CONCLUSIONS: ∆ContCO2/∆ContO2 and ∆PCO2/∆ContO2 ratios are more reliable markers of global anaerobic metabolism than lactate. ScvO2 failed to predict the presence of global tissue hypoxia.