Extracorporeal CO2 removal in acute exacerbation of COPD unresponsive to non-invasive ventilation.

BACKGROUND: The gold-standard treatment for acute exacerbation of chronic obstructive pulmonary disease (ae-COPD) is non-invasive ventilation (NIV). However, NIV failures may be observed, and invasive mechanical ventilation (IMV) is required. Extracorporeal CO2 removal (ECCO2R) devices can be an alternative to intubation. The aim of the study was to assess ECCO2R effectiveness and safety. METHODS: Patients with consecutive ae-COPD who experienced NIV failure were retrospectively assessed over two periods of time: before and after ECCO2R device implementation in our ICU in 2015 (Xenios AG). RESULTS: Both groups (ECCO2R: n=26, control group: n=25) were comparable at baseline, except for BMI, which was significantly higher in the ECCO2R group (30 kg/m² vs 25 kg/m²). pH and PaCO2 significantly improved in both groups. The mean time on ECCO2R was 5.4 days versus 27 days for IMV in the control group. Four patients required IMV in the ECCO2R group, of whom three received IMV after ECCO2R weaning. Seven major bleeding events were observed with ECCO2R, but only three led to premature discontinuation of ECCO2R. Eight cases of ventilator-associated pneumonia were observed in the control group. Mean time spent in the ICU and mean hospital stay in the ECCO2R and control groups were, respectively, 18 vs 30 days, 29 vs 49 days, and the 90-day mortality rates were 15% vs 28%. CONCLUSIONS: ECCO2R was associated with significant improvement of pH and PaCO2 in patients with ae-COPD failing NIV therapy. It also led to avoiding intubation in 85% of cases, with low complication rates. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov, NCT04882410. Date of registration 12 May 2021, retrospectively registered.https://www.clinicaltrials.gov/ct2/show/NCT04882410.

Continuous Positive Airway Pressure (CPAP) face-mask ventilation is an easy and cheap option to manage a massive influx of patients presenting acute respiratory failure during the SARS-CoV-2 outbreak: A retrospective cohort study.

INTRODUCTION: Because of the COVID-19 pandemic, intensive care units (ICU) can be overwhelmed by the number of hypoxemic patients. MATERIAL AND METHODS: This single centre retrospective observational cohort study took place in a French hospital where the number of patients exceeded the ICU capacity despite an increase from 18 to 32 beds. Because of this, 59 (37%) of the 159 patients requiring ICU care were referred to other hospitals. From 27th March to 23rd April, consecutive patients who had respiratory failure or were unable to maintain an SpO2 > 90%, despite receiving 10-15 l/min of oxygen with a non-rebreather mask, were treated by continuous positive airway pressure (CPAP) unless the ICU physician judged that immediate intubation was indicated. We describe the characteristics, clinical course, and outcomes of these patients. The main outcome under study was CPAP discontinuation. RESULTS: CPAP was initiated in 49 patients and performed out of ICU in 41 (84%). Median age was 65 years (IQR = 54-71) and 36 (73%) were men. Median respiratory rate before CPAP was 36 (30-40) and median SpO2 was 92% (90-95) under 10 to 15 L/min oxygen flow. Median duration of CPAP was 3 days (IQR = 1-5). Reasons for discontinuation of CPAP were: intubation in 25 (51%), improvement in 16 (33%), poor tolerance in 6 (12%) and death in 2 (4%) patients. A decision not to intubate had been taken for 8 patients, including the 2 who died while on CPAP. Two patients underwent less than one hour CPAP for poor tolerance. In the end, 15 (38%) out of 39 evaluable patients recovered with only CPAP whereas 24 (62%) were intubated. CONCLUSIONS: CPAP is feasible in a non-ICU environment in the context of massive influx of patients. In our cohort up to 1/3 of the patients presenting with acute respiratory failure recovered without intubation.

Early mechanical ventilation in patients with Guillain-Barré syndrome at high risk of respiratory failure: a randomized trial.

INTRODUCTION: About 30% of patients with Guillain-Barré syndrome become ventilator dependent, of whom roughly 75% develop pneumonia. This trial aimed at assessing the impact of early mechanical ventilation (EMV) on pneumonia occurrence in GBS patients. We hypothesize that EMV will reduce the incidence of pneumonia. METHODS: This was a single centre, open-label, randomized controlled trial performed on two parallel groups. 50 intensive care unit adults admitted for Guillain-Barré syndrome and at risk for acute respiratory failure. Patients were randomized to early mechanical ventilation via face-mask or endotracheal intubation owing to the presence or absence of impaired swallowing (experimental arm), or to conventional care (control arm). The primary outcome was the incidence of pneumonia up to intensive care unit discharge (or 90 days, pending of which occurred first). FINDINGS: Twenty-five patients were randomized in each group. There was no significant difference between groups for the incidence of pneumonia (10/25 (40%) vs 9/25 (36%), P = 1). There was no significant difference between groups for the time to onset of pneumonia (P = 0.50, Gray test). During follow-up, there were 16/25 (64%) mechanically ventilated patients in the control group, and 25/25 (100%) in the experimental arm (P < 000·1). The time on ventilator was non-significantly shorter in the experimental arm (14 [7; 29] versus 21.5 [17.3; 35.5], P = 0.10). There were no significant differences between groups for length of hospital stay, neurological scores, the proportion of patients who needed tracheostomy, in-hospital death, or any serious adverse events. CONCLUSIONS: In the present study including adults with Guillain-Barré syndrome at high risk of respiratory failure, we did not observe a prevention of pneumonia with early mechanical ventilation. TRIAL REGISTRATION: ClinicalTrials.gov under the number NCT00167622. Registered 9 September 2005, https://clinicaltrials.gov/ct2/show/NCT00167622?cond=Guillain-Barre+Syndrome&cntry=FR&draw=2&rank=1.

She Has The Blues: An Unusual Case of Copper Sulphate Intoxication.

BACKGROUND: Copper is an essential trace element of the human body. However, it is related to many diseases. Copper intoxication is not common in Western countries, but needs to be rapidly recognised because of its high lethality. CASE PRESENTATION: We report the case of a 40-year-old woman who presented to the emergency department after performing intrarectal administration of a blue powder sent from Cameroon by her family, in the belief that this would help her to get pregnant. Her evolution was complicated by multiorgan failure and the unusual circumstances. The diagnosis was suspected on the basis of the clinical presentation and the colour of the powder, and confirmed by blood dosage and toxicological analysis of the powder. She underwent symptomatic treatment, and the outcome was progressively favourable, apart from persistent chronic renal failure with dependence on dialysis. CONCLUSION: Copper intoxications are rare but severe. Laboratory diagnosis of the condition is not an issue; the difficulty is suspecting it and quickly initiating chelation treatment associated with symptomatic treatments. LEARNING POINTS: Copper sulphate is a rare but severe condition that must be promptly diagnosed. Diagnosis may be based on clinical presentation, characterised by multiple organ failure, and suspected in the case of ingestion of a blue chemical product.In the presence of saturation gap on pulse oximetry, the clinician must consider the possibility of methemoglobinaemia, and look for toxic causes.Treatment of copper sulphate poisoning requires mainly symptomatic treatment and chelation of copper by oral or IV drugs.

Preclinical septic shock research: why we need an animal ICU.

Animal experiments are widely used in preclinical medical research with the goal of disease modeling and exploration of novel therapeutic approaches. In the context of sepsis and septic shock, the translation into clinical practice has been disappointing. Classical animal models of septic shock usually involve one-sex-one-age animal models, mostly in mice or rats, contrasting with the heterogeneous population of septic shock patients. Many other factors limit the reliability of preclinical models and may contribute to preclinical research failure in critical care, including the host specificity of several pathogens, the fact that laboratory animals are raised in pathogen-free facilities and that organ support techniques are either absent or minimal. Advanced animal models have been developed with the aim of improving the clinical translatability of experimental findings. So-called animal ICUs refer to the preclinical investigation of adult or even aged animals of either sex, using-in case of rats and mice-miniaturized equipment allowing for reproducing an ICU environment at a small animal scale and integrating chronic comorbidities to more closely reflect the clinical conditions studied. Strength and limitations of preclinical animal models designed to decipher the mechanisms involved in septic cardiomyopathy are discussed. This article reviews the current status and the challenges of setting up an animal ICU.

Correction to: Esmolol indirectly stimulates vagal nerve activity in endotoxemic pigs.

Following publication of the original article [1], the author reported these required corrections to Fig. 5 and Fig. 6.

Esmolol indirectly stimulates vagal nerve activity in endotoxemic pigs.

BACKGROUND: There is an increasing interest in beta-blockade as a therapeutic approach to sepsis following consistent experimental findings of attenuation of inflammation and improved survival with beta1 selective antagonist. However, the mechanism of these beneficial effects remains very uncertain. Thus, this study is aimed at investigating the effects of a beta-1 selective blockade on sympathetic/parasympathetic activity in endotoxin-challenged pigs using heart rate variability. The hypothesis is that an adrenergic blockade could promote parasympathetic activity. Indeed, the increase of parasympathetic activity is a mechanism recently described as beneficial in septic states. METHODS: Fifty-one endotoxin-challenged pigs were studied. After 30 min of endotoxin infusion and 30 min of evolution without intervention, the pigs were randomly assigned the placebo or esmolol treatment and were observed for 200 min. Overall heart rate variability was assessed continuously, in the temporal domain by standard deviation of RR intervals (SDNN, ms),and in the frequency domain by spectral powers of low frequency (LF, ms2 × 103/Hz) and high frequency (HF, ms2 × 103/Hz) bands. RESULTS: Variations of power in these frequency bands were interpreted as putative markers of sympathetic (LF) and parasympathetic (HF) activity. In LPS treated animals, Esmolol did not increase SDNN, but instead decreased LF and increased HF power. CONCLUSION: These spectral modifications associated to a beta-blocker treatment after an endotoxemic challenge are interpreted as a significant decrease of sympathetic activity and an indirect increase of vagal autonomic tone.

A Comparative Analysis of Sepsis Identification Methods in an Electronic Database.

OBJECTIVES: To evaluate the relative validity of criteria for the identification of sepsis in an ICU database. DESIGN: Retrospective cohort study of adult ICU admissions from 2008 to 2012. SETTING: Tertiary teaching hospital in Boston, MA. PATIENTS: Initial admission of all adult patients to noncardiac surgical ICUs. INTERVENTIONS: Comparison of five different algorithms for retrospectively identifying sepsis, including the Sepsis-3 criteria. MEASUREMENTS AND MAIN RESULTS: 11,791 of 23,620 ICU admissions (49.9%) met criteria for the study. Within this subgroup, 59.9% were suspected of infection on ICU admission, 75.2% of admissions had Sequential Organ Failure Assessment greater than or equal to 2, and 49.1% had both suspicion of infection and Sequential Organ Failure Assessment greater than or equal to 2 thereby meeting the Sepsis-3 criteria. The area under the receiver operator characteristic of Sequential Organ Failure Assessment (0.74) for hospital mortality was consistent with previous studies of the Sepsis-3 criteria. The Centers for Disease Control and Prevention, Angus, Martin, Centers for Medicare & Medicaid Services, and explicit coding methods for identifying sepsis revealed respective sepsis incidences of 31.9%, 28.6%, 14.7%, 11.0%, and 9.0%. In-hospital mortality increased with decreasing cohort size, ranging from 30.1% (explicit codes) to 14.5% (Sepsis-3 criteria). Agreement among the criteria was acceptable (Cronbach's alpha, 0.40-0.62). CONCLUSIONS: The new organ dysfunction-based Sepsis-3 criteria have been proposed as a clinical method for identifying sepsis. These criteria identified a larger, less severely ill cohort than that identified by previously used administrative definitions. The Sepsis-3 criteria have several advantages over prior methods, including less susceptibility to coding practices changes, provision of temporal context, and possession of high construct validity. However, the Sepsis-3 criteria also present new challenges, especially when calculated retrospectively. Future studies on sepsis should recognize the differences in outcome incidence among identification methods and contextualize their findings according to the different cohorts identified.

Safety of hyperbaric oxygen therapy in mechanically ventilated patients.

BACKGROUND: To evaluate the epidemiology of patients who require mechanical ventilation during hyperbaric oxygen therapy. MATERIALS AND METHODS: One-hundred-fifty patients who required mechanical ventilation during hyperbaric oxygen therapy were prospectively studied during a 6-year period in a French university hyperbaric centre. We analysed the indication of hyperbaric oxygen therapy, agent used for sedation, presence of a chest tube, need for vasopressor agents and tolerance and appearance of side effects. Finally, we compared the outcomes of patients according to the presence or absence of acute respiratory distress syndrome (ARDS). RESULTS: Eleven children and 139 adult patients were included (n = 150) in the study. In both populations, carbon monoxide poisoning (51%) and iatrogenic gas embolism (33%) were the two main causes of intubation and mechanical ventilation. The combination of midazolam and sufentanil was used in 85 (67%) patients. All of the patients were given a bolus of a neuromuscular blocker during the hyperbaric session, despite the presence of ARDS in 35 patients. Patient-ventilator asynchrony was the most frequent side effect in 6 (5%) patients and was often the consequence of suboptimal sedation. Mortality was higher in the group with ARDS (23%). CONCLUSIONS: Carbon monoxide poisoning and iatrogenic gas embolism are the two main diseases of the patients who required mechanical ventilation during hyperbaric oxygen therapy in this study. Mechanical ventilation is a safe method for patients during hyperbaric oxygen therapy. Sedation needs to be perfected to avoid patient-ventilator asynchrony.

Correlation between clinical severity and different non-invasive measurements of carbon monoxide concentration: A population study.

OBJECTIVES: Carbon monoxide (CO) poisoning is a major concern in industrialized countries. Each year, thousands of victims, resulting in approximately 100 fatalities, are encountered in France. The diagnosis of CO poisoning is challenging; while carboxyhemoglobin (COHb) may be useful, it is a weak indicator of the severity of CO poisoning. This weak indicator may be a result of the delay between poisoning occurrence and the blood assay. Two apparatuses, CO oximeters and exhaled CO analyzers, now permit COHb to be determined outside hospitals. Our hypothesis is that these instruments allow the early measurement of COHb concentrations, which are more correlated with the severity of poisoning, expressed using the poisoning severity score (PSS). DESIGN: In an observational and retrospective cohort study, the distribution of COHb measurements obtained by CO oximetry or by exhaled CO analyzers was compared between groups of severity expressed using the PSS. SETTING: Data were collected in the Paris area from January 2006 to December 2010 by the French Surveillance System of CO poisoning. PARTICIPANTS: All patients with CO poisoning reported to the French Surveillance System of CO poisoning. RESULTS: There was a significant difference in the COHb values obtained by CO oximetry between groups stratified according to PSS (p<0.0001). A significant difference in the values of exhaled CO was also observed between PSS groups (p = 0.006), although the relationship was not linear. CONCLUSIONS: The COHb concentrations measured using CO oximetry, but not those measured using exhaled CO analyzers, were well correlated with the severity of CO poisoning.

A "datathon" model to support cross-disciplinary collaboration.

In recent years, there has been a growing focus on the unreliability of published biomedical and clinical research. To introduce effective new scientific contributors to the culture of health care, we propose a "datathon" or "hackathon" model in which participants with disparate, but potentially synergistic and complementary, knowledge and skills effectively combine to address questions faced by clinicians. The continuous peer review intrinsically provided by follow-up datathons, which take up prior uncompleted projects, might produce more reliable research, either by providing a different perspective on the study design and methodology or by replication of prior analyses.

Criteria for initiation of invasive ventilation in septic shock: An international survey.

PURPOSE: The objective of this study is to record intensivists' beliefs on indications and modalities of ventilatory support in critically ill patients with septic shock. METHODS: The instrument is a 23-items questionnaire, sent to all members of the Systemic Inflammation and Sepsis section of the European Society of Intensive Care Medicine. RESULTS: A total of 186 intensivists from 30 countries completed the survey. For 95% of respondents, intubation should be performed in patients with neurologic or respiratory failure. There was much less consensus about cardiovascular failure as a reason for initiation of invasive mechanical ventilation. Among the 7 hemodynamic criteria proposed, none achieved strong agreement. Among respiratory criteria, hypoxemia, signs of respiratory distress, and cyanosis were the most strongly associated with the will to intubate. Among neurologic criteria, a Glasgow score lower than 8 was strongly associated with the will to intubate. Strikingly, 51% of respondents believed that invasive mechanical ventilation would worsen patients with septic shock, mainly through hemodynamic deterioration (70.4%). CONCLUSIONS: This survey highlights the general belief that invasive mechanical ventilation may worsen hemodynamic status in patients with septic shock. There was general agreement with the mandatory need to initiate mechanical ventilation in patients with respiratory failure and coma, but with little respect to hemodynamic criteria.

Changing use of noninvasive ventilation in critically ill patients: trends over 15 years in francophone countries.

PURPOSE: Over the last two decades, noninvasive ventilation (NIV) has been proposed in various causes of acute respiratory failure (ARF) but some indications are debated. Current trends in NIV use are unknown. METHODS: Comparison of three multicenter prospective audits including all patients receiving mechanical ventilation and conducted in 1997, 2002, and 2011 in francophone countries. RESULTS: Among the 4132 patients enrolled, 2094 (51%) required ventilatory support for ARF and 2038 (49 %) for non-respiratory conditions. Overall NIV use was markedly increased in 2010/11 compared to 1997 and 2002 (37% of mechanically ventilated patients vs. 16% and 28%, P < 0.05). In 2010/11, the use of first-line NIV for ARF had reached a plateau (24% vs. 16% and 23%, P < 0.05) whereas pre-ICU and post-extubation NIV had substantially increased (11% vs. 4% and 11% vs. 7%, respectively, P < 0.05). First-line NIV remained stable in acute-on-chronic RF, continued to increase in cardiogenic pulmonary edema, but decreased in de novo ARF (16% in 2010/11 vs. 23% in 2002, P < 0.05). The NIV success rate increased from 56% in 2002 to 70% in 2010/11 and remained the lowest in de novo ARF. NIV failure in de novo ARF was associated with increased mortality in 2002 but not in 2010/11. Mortality decreased over time, and overall, NIV use was associated with a lower mortality. CONCLUSION: Increases in NIV use and success rate, an overall decrease in mortality, and a decrease of the adverse impact NIV failure has in de novo ARF suggest better patient selection and greater proficiency of staff in administering NIV. TRIAL REGISTRATION: Clinicaltrials.gov Identifier NCT01449331.

StO2 guided early resuscitation in subjects with severe sepsis or septic shock: a pilot randomised trial.

The scientific community has agreed upon developing accurate monitoring of tissue perfusion and oxygenation to improve the management of subjects with sepsis. This pilot study aimed to investigate the feasibility of targeting tissue oxygen saturation (StO2) in addition to the currently recommended resuscitation goals, central venous pressure, mean arterial pressure and central venous oxygen saturation, in patients with severe sepsis or septic shock. A pilot, single-centre, randomised, non-blinded trial recruited 30 subjects with severe sepsis upon intensive care unit admission at an academic medical centre in France. Subjects were randomly assigned to a 6 h resuscitation strategy following the Surviving Sepsis Campaign guidelines with (experimental) or without (control) StO2. StO2 was measured over several muscles (masseter, deltoid and pectoral or thenar muscles), and a StO2 above 80 % over at least 2 muscles was the therapeutic goal. The primary outcome was evaluated as follows: 7-day mortality or worsening of SOFA score between day 7 and study onset, i.e., DSOFA > 0). Thirty subjects were included in the study over a period of 40 weeks. Fifteen subjects were included in each group. Monitoring of StO2 over three areas was performed in the experimental group. However, measures over the pectoral muscle provided poor results. At study day 7, there were 5/15 (33.3 %) subjects who died or had a DSOFA > 0 in the experimental arm and 4/15 (26.6 %) who died or had a DSOFA > 0 in the control arm (p = 1.00). This pilot study was the first randomised controlled trial using an algorithm derived from the SSC recommendations, which included StO2 as a treatment goal. However, the protocol showed no clear trend for or against targeting StO2.

Decompression sickness in urban divers in France.

BACKGROUND: Decompression sickness (DCS) can occur in SCUBA divers. DCS is treated with oxygen, preferably given under hyperbaric conditions. Although Paris (France) is located at a distance from the sea or lakes, some injured divers require hyperbaric oxygen treatment (HBOT) in this city, sometimes within a specific time frame. Thus, this study investigated the epidemiology and outcomes of such urban divers. AIM: We conducted an observational study of SCUBA divers admitted to the Raymond Poincaré Hyperbaric centre near Paris from 1993 to 2003. MATERIALS AND METHODS: We prospectively enrolled 69 consecutive SCUBA divers presenting DCS. Common risk factors were reported, especially aeroplane flight and training dives. Symptoms are very often atypical (63%) and onset time of symptoms is often too long (59% after 2 h) due to denial of symptoms. First aid is generally inadequate, with only 23% of victims receiving oxygen, fluid loading and aspirin together. HBOT was given for 42 (61%) patients although their examination results were considered as normal. CONCLUSIONS: Diving pits and diving travel agencies should do more to warn divers of the need for treatment with normobaric oxygen and hydration pending HBOT. Moreover, hyperbaric physicians should better clarify HBOT indications for both symptoms of late onset and atypical presentations.

[Septic shock treatment concerns]. / Les enjeux du traitement du choc septique.

The establishment of care procedures in the treatment of septic shock may decrease the risk of mortality. Prognosis of this condition may improve through teamwork in the Intensive Care Unit.

Dead space and CO2 elimination related to pattern of inspiratory gas delivery in ARDS patients.

INTRODUCTION: The inspiratory flow pattern influences CO2 elimination by affecting the time the tidal volume remains resident in alveoli. This time is expressed in terms of mean distribution time (MDT), which is the time available for distribution and diffusion of inspired tidal gas within resident alveolar gas. In healthy and sick pigs, abrupt cessation of inspiratory flow (that is, high end-inspiratory flow (EIF)), enhances CO2 elimination. The objective was to test the hypothesis that effects of inspiratory gas delivery pattern on CO2 exchange can be comprehensively described from the effects of MDT and EIF in patients with acute respiratory distress syndrome (ARDS). METHODS: In a medical intensive care unit of a university hospital, ARDS patients were studied during sequences of breaths with varying inspiratory flow patterns. Patients were ventilated with a computer-controlled ventilator allowing single breaths to be modified with respect to durations of inspiratory flow and postinspiratory pause (TP), as well as the shape of the inspiratory flow wave. From the single-breath test for CO2, the volume of CO2 eliminated by each tidal breath was derived. RESULTS: A long MDT, caused primarily by a long TP, led to importantly enhanced CO2 elimination. So did a high EIF. Effects of MDT and EIF were comprehensively described with a simple equation. Typically, an efficient and a less-efficient pattern of inspiration could result in ± 10% variation of CO2 elimination, and in individuals, up to 35%. CONCLUSIONS: In ARDS, CO2 elimination is importantly enhanced by an inspiratory flow pattern with long MDT and high EIF. An optimal inspiratory pattern allows a reduction of tidal volume and may be part of lung-protective ventilation.

Masseter tissue oxygen saturation predicts normal central venous oxygen saturation during early goal-directed therapy and predicts mortality in patients with severe sepsis.

OBJECTIVE: This study aimed to investigate, in patients with severe sepsis, the correlation between central venous oxygen saturation and tissue oxygen saturation at different levels. DESIGN: Prospective observational study. SETTING: General intensive care unit at an academic medical center in France. PATIENTS: Thirty-eight patients with underresuscitated severe sepsis and septic shock on intensive care unit admission. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: During early resuscitation according to the 6-hr bundles of the Surviving Sepsis Campaign guidelines, tissue oxygen saturation was recorded every other hour at the level of the thenar, masseter, and deltoid muscles along with central hemodynamics, arterial lactate concentrations, and central venous oxygen saturation. Over the 6-hr resuscitation period, thenar tissue oxygen saturation was consistently higher than masseter tissue oxygen saturation (p = .04) and deltoid tissue oxygen saturation (p = .002), and masseter tissue oxygen saturation was consistently higher than deltoid tissue oxygen saturation (p = .04). Receiver operating characteristic curves analyses showed that masseter tissue oxygen saturation was better predictor of central venous oxygen saturation >70% than thenar tissue oxygen saturation (area under the curve, 0.80; 95% confidence interval 0.71-0.89 vs. 0.67; 95% confidence interval 0.56-0.77; p = .02). The crude 28-day mortality was 36.8%. Receiver operating characteristic curve analysis showed that masseter tissue oxygen saturation (area under the curve 0.87; 0.75-0.98) and deltoid tissue oxygen saturation (area under the curve 0.88; 0.77-0.98) but not thenar tissue oxygen saturation (area under the curve 0.66; 0.46-0.86) or central venous oxygen saturation (area under the curve 0.56; 0.38-0.80) were strong predictors of 28-day mortality. CONCLUSIONS: This study suggested that in the early 6-hr resuscitation period, masseter tissue oxygen saturation accurately identified patients with severe sepsis and central venous oxygen saturation >70%. Both masseter tissue oxygen saturation and deltoid tissue oxygen saturation but not central venous oxygen saturation or thenar tissue oxygen saturation are strong predictors of 28-day mortality.

Effects of esmolol on systemic and pulmonary hemodynamics and on oxygenation in pigs with hypodynamic endotoxin shock.

PURPOSE: The aim of this experimental study is to investigate cardiovascular tolerance of blockade of beta-adrenergic receptors in an endotoxin model. DESIGN: Prospective, randomized, controlled study. SETTING: Animal laboratory in a university medical center. METHODS: Ten anesthetized, mechanically ventilated pigs were challenged with intravenous lipopolysaccharide (LPS) to achieve a status of profound hypodynamic shock. Systemic and pulmonary hemodynamics and cardiac output were continuously monitored throughout the 5-h study period, and blood samples were taken at baseline (T - 30 min), 1 h from the beginning of LPS infusion (T + 60 min), and every 2 h (T + 180 min and T + 300 min). Animals were randomly assigned to continuous intravenous esmolol infusion titrated to decrease heart rate by 20% or isotonic saline. RESULTS: Esmolol decreased heart rate by 20%, while in the saline group, heart rate increased by 7% and 22% at T + 180 min and T + 300 min, respectively (p < 0.001). In esmolol-treated animals, cardiac index decreased by 9% at T + 180 min and by 2% at T + 300 min, and in controls by 14% at T + 180 min and by 27% at T + 300 min (p = 0.870). In esmolol-treated animals, median (interquartile range, IQR) stroke index was 31 (6) and 47 (11) ml/min/m(2) at T + 180 min and T + 300 min, respectively, and decreased steadily from 45 (20) to 18 (13) ml/min/m(2) in controls (p = 0.030). There were no significant differences between groups for any other hemodynamics variables, except for systemic vascular resistance (SVR) (p = 0.017). CONCLUSIONS: In large animals with endotoxemic shock, continuous infusion of esmolol, a selective beta-1 adrenergic blocker, titrated to decrease heart rate by 20%, was well tolerated and may offset LPS-induced cardiac dysfunction by a preload positive effect.