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Daniel De Backer

Publications and source records attributed to Daniel De Backer.

54 records · Page 3Linked to original sources
PubMed2003

Low-dose vasopressin in the treatment of septic shock in sheep.

After induction of cecal perforation, 20 anesthetized sheep were randomized to be treated, when arterial blood pressure fell below 75 mm Hg, with vasopressin (fixed dose of 0.02 U/minute), norepinephrine (0.5-5 microg/kg/minute titrated to maintain mean arterial pressure between 75 and 85 mm Hg), vasopressin + norepinephrine (vasopressin at fixed dose 0.01 U/minute plus norepinephrine titrated as for norepinephrine only group), or no vasopressor (Ringer's lactate [control]). Mean arterial pressure was well maintained in all treatment groups. Superior mesenteric arterial blood flow was significantly lower in the vasopressin + norepinephrine group than in the vasopressin group. Vasopressin alone or combined with norepinephrine limited the increase in blood lactate concentration and ileal PCO2-gap compared with control and norepinephrine groups. Urine output was higher in the vasopressin group than in control and norepinephrine groups. Survival time was longer in the vasopressin (30 +/- 6 hours) and vasopressin + norepinephrine (30 +/- 3 hours) groups than in the norepinephrine group (20 +/- 1 hours, p < 0.05) and in all treatment groups than in the control group (17 +/- 2 hours, p < 0.05). Tissue injury was less severe in the vasopressin and vasopressin + norepinephrine groups than in the others. In this clinically relevant model of septic shock due to peritonitis, vasopressin administration (alone or with norepinephrine) can prolong survival.

Animals↗
PubMed2003

Effect of vasopressin on sublingual microcirculation in a patient with distributive shock.

OBJECTIVE: To assess the sublingual microcirculation in a patient during vasopressin administration for a distributive shock after cardiopulmonary bypass. DESIGN AND SETTING: Case-report in the Department of Intensive Care of a university hospital. PATIENT: A 53 year-old man developed severe distributive shock after cardiac transplant, requiring massive doses of vasopressor agents. METHODS: Vasopressin administered twice at a dose of 0.02 U/min increased mean blood pressure and allowed partial weaning of other vasopressor drugs. Microcirculatory alterations were assessed by orthogonal polarization spectral technique: 50% and 60% of capillaries were perfused at baseline, and these proportions did not worsen when vasopressin was administered. CONCLUSIONS: Despite its strong vasopressor effects vasopressin infusion did not worsen microcirculatory alterations in this patient with distributive shock following cardiac surgery.

Blood Pressure↗
PubMed2003

Lactic acidosis.

Explore the source record for details and available documents.

Acidosis, Lactic↗
PubMed2003

Optimal adrenergic support in septic shock due to peritonitis.

BACKGROUND: The authors evaluated optimal adrenergic support using norepinephrine, dopamine, and dobutamine in a clinically relevant model of septic shock. METHODS: Twenty-eight mature, female, anesthetized sheep (weight, 30.5 +/- 3.6 kg) underwent cecal ligation and perforation and were randomized into four groups of seven animals to be treated with norepinephrine, dopamine-norepinephrine, dobutamine-norepinephrine, or no adrenergic agent. In all groups, lactated Ringer's solution was administered to restore cardiac filling pressures to baseline. In the norepinephrine group, norepinephrine (0.5-5 microg. kg(-1). min(-1)) was titrated to maintain mean arterial pressure between 75-85 mmHg. In the dopamine-norepinephrine group, dopamine was given first, and norepinephrine was added only when mean arterial pressure remained below 75 mmHg despite the infusion of 20 microg. kg(-1). min(-1) dopamine. In the dobutamine-norepinephrine group, dobutamine was started at the same time as norepinephrine and titrated up to 20 microg. kg(-1). min(-1) to get a 15% increase in cardiac output. RESULTS: The dobutamine-norepinephrine group had greater cardiac output; superior mesenteric blood flow, oxygen delivery (Do(2)), and oxygen consumption ([OV0312]o(2)); and lower blood lactate concentration and partial pressure of carbon dioxide (Pco(2)) gap than the controls did. Cumulative urine output was significantly higher in the dobutamine-norepinephrine group than in the other groups. Survival time was significantly longer in the dobutamine-norepinephrine (24 +/- 4 h), dopamine- norepinephrine (24 +/- 6 h), and norepinephrine (20 +/- 1 h) groups than the control group (17 +/- 2 h; P < 0.05 vs. other groups), and significantly longer in the combined dopamine-norepinephrine and dobutamine-norepinephrine groups (24 +/- 5 h) than in the norepinephrine alone group (P < 0.05). Histologic examination of lung biopsies revealed less severe lesions in the dobutamine-norepinephrine group than in the control and norepinephrine alone groups. Anatomic alterations in the lung, liver, and small intestine were less severe in the dobutamine-norepinephrine group than in the other groups. CONCLUSIONS: In this prolonged septic shock model, association of norepinephrine with either dopamine or dobutamine resulted in the longest survival and the least severe pulmonary lesions. The combination of dobutamine with norepinephrine was associated with a better myocardial performance, greater Do(2) and [OV0312]o(2), lower blood lactate concentration and Pco(2) gap, and less anatomic injury.

Adrenergic Agents↗
PubMed2003

Effects of dopamine, norepinephrine, and epinephrine on the splanchnic circulation in septic shock: which is best?

OBJECTIVE: To assess the effects of different doses of dopamine, norepinephrine, and epinephrine on the splanchnic circulation in patients with septic shock. DESIGN: Prospective, randomized, open-label study. SETTING: A 31-bed, medicosurgical intensive care unit of a university hospital. PATIENTS: Convenience sample of 20 patients with septic shock, separated into two groups according to whether (moderate shock group, n = 10) or not (severe shock, n = 10) dopamine alone was able maintain mean arterial pressure >65 mm Hg. INTERVENTIONS: Dopamine was progressively withdrawn and replaced successively by norepinephrine and then epinephrine (the order of the two agents was randomly determined) to maintain mean arterial pressure constant (moderate shock) or to increase mean arterial pressure above 65 mm Hg (severe shock). MEASUREMENTS AND MAIN RESULTS: Systemic circulation (pulmonary artery catheter) and splanchnic circulation (indocyanine green dilution and hepatic vein catheter) and gastric mucosal Pco(2) (gas tonometry) were measured during dopamine (moderate shock only), norepinephrine, and epinephrine administration (both groups). Data were analyzed with nonparametric tests and are presented as median [percentiles 25-75]. In moderate shock, cardiac index was similar to dopamine and norepinephrine (3.1 [2.7-3.8] vs. 2.9 [2.7-4.1] L/min.m2, p = nonsignificant) but greater with epinephrine (4.1 [3.5-4.4] p <.01 vs. dopamine and norepinephrine). Splanchnic blood flow was similar with the three agents (732 [413-1483] vs. 746 [470-1401] vs. 653 [476-1832] mL/min.m, p = nonsignificant). The gradient between mixed-venous and hepatic venous oxygen saturations was lower with dopamine than with norepinephrine and epinephrine, but the Pco(2) gap was similar with the three agents. In severe shock, cardiac index was higher, but splanchnic blood flow was lower, with epinephrine than with norepinephrine (4.6 [3.7-5.3] vs. 3.4 [3.0-4.1] L/min.m2, p <.01 and 860 [684-1334] vs. 977 [806-1802] mL/min.m2, p <.05, respectively). Epinephrine increased the mixed-venous and hepatic venous oxygen saturation gradient but did not alter Pco(2) gap. CONCLUSIONS: Dopamine and norepinephrine have similar hemodynamic effects, but epinephrine can impair splanchnic circulation in severe septic shock.

Aged↗
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

The cuff leak test to predict failure of tracheal extubation for laryngeal edema.

OBJECTIVE: Laryngeal edema secondary to endotracheal intubation may require early re-intubation. Prior to extubation the absence of leak around an endotracheal tube may predict laryngeal edema after extubation. We evaluated the usefulness of a quantitative assessment of such a leak to identify the patients who will require early re-intubation for laryngeal edema. METHODS: This prospective study included 76 patients with endotracheal intubation for more than 12 h. The leak, in percent, was defined as the difference between expired tidal volume measured just before extubation, in volume-controlled mode, with the cuff inflated and then deflated. The best cut-off value to predict the need for re-intubation for significant laryngeal edema was determined and the patients were divided into two groups, according to this cut-off value. RESULTS: Eight of the 76 patients (11%) needed re-intubation for laryngeal edema. Patients requiring re-intubation had a smaller leak than the other patients [9 (3-18) vs 35 (13-53)%, p<0.01]. The best cut-off value for gas leak was 15.5%. The high leak group included 51 patients, of whom only two patients (3%) required re-intubation. The low leak group included 25 patients, among whom six patients (24%) required re-intubation ( p<0.01). The sensitivity of this test was 75%, the specificity 72.1%, the positive predictive value 25%, the negative predictive value 96.1% and the percent of correct classification 72.4%. CONCLUSIONS: A gas leak around the endotracheal tube greater than 15.5% can be used as a screening test to limit the risk of re-intubation for laryngeal edema.

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

Management of septic shock.

Severe sepsis is a common disease process affecting some 2-11% of hospital admissions in the US. Severe sepsis and septic shock are associated with considerable morbidity and mortality, and account for a large part of intensive care unit costs. Until recently, the management of septic shock relied on the treatment of underlying infection with antimicrobial agents and surgical removal of any infectious source, and individual support of failing organs. However, in the last few years we have seen huge strides being made in our understanding of the pathophysiology of the sepsis response, and in our ability to manipulate that response. In the last couple of years these advances have come to fruition with the development of a drug, drotrecogin alfa, which specifically reduces mortality from this all too often fatal disease. While intensive early resuscitation remains the cornerstone of management, new approaches are beginning to form part of sepsis management protocols and will lead to improved outcomes for patients with this disease process.

Adjuvants, Immunologic↗