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Marc-Jacques Dubois

Publications and source records attributed to Marc-Jacques Dubois.

10 recordsLinked to original sources
PubMed2004

Microvascular alterations in patients with acute severe heart failure and cardiogenic shock.

BACKGROUND: Microvascular blood flow alterations may impair tissue oxygenation and may participate in the development of multiple organ failure in patients with severe heart failure. We hypothesized that microvascular blood flow alterations are present in patients with severe heart failure and cardiogenic shock. METHODS: We used an orthogonal polarization spectral imaging technique to investigate the sublingual microcirculation in 40 patients with acute severe heart failure, including 31 patients with cardiogenic shock, and in a control group of 15 patients who were examined the day before cardiac surgery. The effects of topical application of acetylcholine (10-2M) were also tested in 5 patients with cardiogenic shock. Five sublingual areas were recorded, allocated a random number, and later analyzed semiquantitatively. Data were analyzed with non-parametric tests and presented as medians (percentiles 25-75). RESULTS: The density of all the vessels was similar in the 3 groups. The proportion of perfused small (<20 microm) vessels was lower in patients with cardiac failure and cardiogenic shock than in control patients (63% [46%-65%] and 49% [38%-64%] vs 92% [90%-93%], P <.001). The perfusion of large vessels was preserved in all groups. The proportion of perfused vessels was higher in patients who survived than in patients who did not survive in all vessels (90% [84%-93%] vs 81% [74%-87%], P <.05) and in small vessels (64% [49%-68%] vs 43% [37%-62%], P <.05). The topical application of acetylcholine totally reversed these alterations CONCLUSIONS: Microvascular blood flow alterations are frequently observed in patients with severe heart failure and are more severe in patients who do not survive.

Acetylcholine↗
PubMed2004

Normality.

Explore the source record for details and available documents.

Biomarkers↗
PubMed2004

Persistent microcirculatory alterations are associated with organ failure and death in patients with septic shock.

OBJECTIVE: To characterize the time course of microcirculatory alterations and their relation to outcome in patients with septic shock. DESIGN: Prospective, observational study. SETTING: Thirty-one-bed, medico-surgical intensive care unit in a university hospital. PATIENTS: Forty-nine patients with septic shock. INTERVENTIONS: The sublingual microcirculation was investigated with an orthogonal polarization spectral imaging device on the day of onset of septic shock (baseline) and each day until resolution of shock. MEASUREMENTS AND MAIN RESULTS: Five sequences of 20 secs each were recorded and analyzed off-line by a semiquantitative method. Data were analyzed with nonparametric tests and presented as median (25th-75th percentiles). Three patients died after the resolution of shock from unrelated causes and were excluded. Of the other 46 patients, 26 survived and 20 died: 13 due to unresolving shock and seven due to persistent multiple organ failure after resolution of shock. At the onset of shock, survivors and nonsurvivors had similar vascular density (5.6 [4.7-7.0] vs. 6.2 [5.4-7.0]/mL; p = nonsignificant) and percentage of perfused small vessels (65.0 [53.1-68.9] vs. 58.4 [47.5-69.1]%; p = nonsignificant). Small vessel perfusion improved over time in survivors (analysis of variance, p <.05 between survivors and nonsurvivors) but not in nonsurvivors. Despite similar hemodynamic and oxygenation profiles and use of vasopressors at the end of shock, patients dying after the resolution of shock in multiple organ failure had a lower percentage of perfused small vessels than survivors (57.4 [46.6-64.9] vs. 79.3 [67.2-83.2]%; p =.02). CONCLUSIONS: Microcirculatory alterations improve rapidly in septic shock survivors but not in patients dying with multiple organ failure, regardless of whether shock has resolved.

Aged↗
PubMed2003

Hypoalbuminemia in acute illness: is there a rationale for intervention? A meta-analysis of cohort studies and controlled trials.

OBJECTIVE: To determine whether hypoalbuminemia is an independent risk factor for poor outcome in the acutely ill, and to assess the potential of exogenous albumin administration for improving outcomes in hypoalbuminemic patients. SUMMARY BACKGROUND DATA: Hypoalbuminemia is associated with poor outcomes in acutely ill patients, but whether this association is causal has remained unclear. Trials investigating albumin therapy to correct hypoalbuminemia have proven inconclusive. METHODS: A meta-analysis was conducted of 90 cohort studies with 291,433 total patients evaluating hypoalbuminemia as an outcome predictor by multivariate analysis and, separately, of nine prospective controlled trials with 535 total patients on correcting hypoalbuminemia. RESULTS: Hypoalbuminemia was a potent, dose-dependent independent predictor of poor outcome. Each 10-g/L decline in serum albumin concentration significantly raised the odds of mortality by 137%, morbidity by 89%, prolonged intensive care unit and hospital stay respectively by 28% and 71%, and increased resource utilization by 66%. The association between hypoalbuminemia and poor outcome appeared to be independent of both nutritional status and inflammation. Analysis of dose-dependency in controlled trials of albumin therapy suggested that complication rates may be reduced when the serum albumin level attained during albumin administration exceeds 30 g/L. CONCLUSIONS: Hypoalbuminemia is strongly associated with poor clinical outcomes. Further well-designed trials are needed to characterize the effects of albumin therapy in hypoalbuminemic patients. In the interim, there is no compelling basis to withhold albumin therapy if it is judged clinically appropriate.

Acute Disease↗
PubMed2003

Do all nonsurvivors of cardiogenic shock die with a low cardiac index?

STUDY OBJECTIVES: To characterize the hemodynamic course of cardiogenic shock and to relate the cause of death to ongoing cardiac failure or multiple organ dysfunction. DESIGN: Retrospective study. SETTING: A 31-bed department of intensive care in a university hospital. PATIENTS: All patients admitted for cardiogenic shock from January 1999 to December 2000. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Charts were reviewed for demographic, clinical, hemodynamic, oxygen transport, inflammation, and organ dysfunction data. Of 62 patients with cardiogenic shock, 40 (65%) did not survive. Eight patients (20%) died from fatal arrhythmia, 14 patients (35%) died with low cardiac index (CI) [ie, < 2.2 L/min/m(2)], and 18 patients (45%) died with normalized CI (ie, > 2.2 L/min/m(2)) and a higher CI/oxygen extraction ratio. Of these 18 patients, 9 had evidence of infection. The patients with normalized CI were younger and stayed longer in the ICU than patients with low CI. CONCLUSION: A substantial number of patients with cardiogenic shock die with a normalized CI, suggesting a distributive defect, in the absence of obvious infection. These patients are younger and have a longer ICU course. The release of mediators may be secondary to gut hypoperfusion.

Aged↗
PubMed2002

Microvascular blood flow is altered in patients with sepsis.

Microvascular blood flow alterations are frequent in animal models of sepsis and may impair tissue oxygenation. We hypothesized that alterations of the microcirculation are present in patients with sepsis. We used an orthogonal polarization spectral imaging technique to investigate the sublingual microcirculation in 10 healthy volunteers, 16 patients before cardiac surgery, 10 acutely ill patients without sepsis (intensive care unit control subjects), and 50 patients with severe sepsis. The effects of topical application of acetylcholine (10(-2) M) were tested in 11 patients with sepsis. In each subject, five to seven sublingual areas were recorded and analyzed semiquantitatively. Data were analyzed with nonparametric tests and are presented as medians (25th-75th percentiles). No significant difference in microvascular blood flow was observed between healthy volunteers and patients before cardiac surgery or intensive care unit control subjects. The density of all vessels was significantly reduced in patients with severe sepsis (4.5 [4.2-5.2] versus 5.4 [5.4-6.3]/mm in volunteers, p < 0.01). The proportion of perfused small (< 20 microm) vessels was reduced in patients with sepsis (48 [33-61] versus 90 [89-92]% in volunteers, p < 0.001). These alterations were more severe in nonsurvivors. The topical application of acetylcholine totally reversed these alterations. In conclusion, microvascular blood flow alterations are frequent in patients with sepsis and are more severe in patients with a worse outcome.

Acetylcholine↗
PubMed2002

Delirium in critically ill patients.

Delirium in the intensive care unit is a serious problem that has recently attracted much attention. User-friendly and reliable tools, such as the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU), offer the clinician the opportunity to identify delirium in patients better. Diagnosis of delirium in a critical care population is often a difficult task because classical psychiatric evaluation is impossible for a number of reasons. The CAM-ICU makes use of nonverbal assessments to evaluate the cardinal features of delirium (i.e. acute or fluctuating onset, inattention, disorganized thinking and altered level of consciousness). Its development for use in the critical care setting represents a significant advance that could lead to better care for such patients.

Critical Illness↗
PubMed2002

Clinical trials of immunomodulatory therapies in severe sepsis and septic shock.

Sepsis remains one of the leading causes of mortality in critically ill patients. Increased insight into the complexities of this disease process has resulted in the targeting of various aspects of the inflammatory response as offering potential therapeutic benefits. There have been encouraging results in the past few years. Some of the tested agents have been shown to improve mortality rates in large randomized controlled trials involving patients with severe sepsis. In this article, we discuss the positive and negative results of trials in this field; some of the possible reasons for the negative results are examined, and directions for the future are suggested.

Antitoxins↗
PubMed2002

Use of albumin in the intensive care unit.

Recent publications have renewed interest in albumin use in the ICU. Meta-analyses have been published that demonstrate the safety of albumin administration and even potential benefits. Hypoalbuminemia, which has long been considered a marker of disease, has been causally linked to the development of complications. Finally, advances have been made in our knowledge of the unique and potentially beneficial properties of albumin.

Albumins↗