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D Dreyfuss

Publications and source records attributed to D Dreyfuss.

At least 55 records · Page 3Linked to original sources
PubMed1996

Atrial septal aneurysm plus a patent foramen ovale. A predisposing factor for paradoxical embolism and refractory hypoxemia during pulmonary embolism.

We report three consecutive cases of patients who had refractory hypoxemia and paradoxical embolism during the course of pulmonary embolism. Transesophageal echocardiography showed an atrial septal aneurysm and a patent foramen ovale in all patients. The latter was detected by an early and massive passage of contrast from the right to the left atrium. We suggest that the presence of an atrial septal aneurysm plus a patent foramen ovale greatly enhances both magnitude of shunting and the risk of systemic embolism. The presence of an atrial septal aneurysm plus a patent foramen ovale should be considered and checked using transesophageal echocardiography in every patient with significant pulmonary embolism.

Aged↗
PubMed1996

Comparison of the effects of heat and moisture exchangers and heated humidifiers on ventilation and gas exchange during weaning trials from mechanical ventilation.

Heat and moisture exchangers (HME) are increasingly used to warm and humidify inspired gases in intubated ventilated patients. But these devices add dead space that may alter the alveolar ventilation. This could impair the efficiency of spontaneous ventilation (SV) during weaning trials from mechanical ventilation. Fifteen patients were tested with an HME (Hygrobac-DAR) and a heated humidifier (HH) (Fischer-Paykel MR 450) in a random order during weaning trials in SV with inspiratory pressure support. Minute ventilation VE, tidal volume), and respiratory rate were recorded and arterial blood was sampled for blood gas analysis with each device. The HME gave a significantly greater VE than the HH (9.3 +/- 0.8 L/min vs 8.1 +/- 0.8 L/min; p < 0.005), because of increased respiratory rate (21 +/- 2/min vs 19 +/- 2/min; p < 0.05). Tidal volume was unchanged for HME and HH (470 +/- 32 mL vs 458 +/- 39 mL). The higher PaCO2 with HME than with HH (44 +/- 2 mm Hg vs 42 +/- 2 mm Hg; p < 0.005) revealed an insufficient alveolar ventilation response to the increase in dead space. Arterial Po2 rose with the HME, but not significantly above the HH values (103 +/- 6 mm Hg vs 97 +/- 6 mm Hg; p = 0.055), possibly because of a positive end-expiratory pressure effect of the HME. The need to increase VE in SV when an HME is used should be taken into account during difficult weaning from mechanical ventilation.

Adult↗
PubMed1995

Mechanical ventilation-induced pulmonary edema. Interaction with previous lung alterations.

The risk of lung injury due to alveolar overdistension during mechanical ventilation has been clearly delineated in healthy animals with intact lungs. In contrast, the effect of high-volume ventilation (HV) on previously injured lungs is less well documented: whether HV would simply add its own deleterious effects or act synergistically with previous injury has not been addressed. We compared the effect of 7 ml/kg body weight tidal volume mechanical ventilation for 2 min with that of 25 (HV25), 33(HV33), and 45(HV45) ml/kg body weight HV in anesthetized rats previously exposed or not exposed to alpha-naphthylthiourea (ANTU). ANTU alone produced moderate permeability edema with significant increases in extravascular lung water (Qwl), dry lung weight (DLW), and albumin distribution space in lungs (ASp). HV alone resulted in a permeability edema in which severity was dependent on the magnitude of the tidal volume. The effects of HV25 and HV33 and those of ANTU were only additive, as indicated by the absence of any significant two-factor (ANTU-HV) interaction by analysis of variance (ANOVA). In contrast, HV45 after ANTU produced significantly greater increases in Qwl, DLW, and ASp than expected from the sum of the effects of either insult alone. Two-way ANOVA disclosed two-factor interactions with p values < 0.001, < 0.02, and < 0.01 for Qwl, DLW, and ASp, respectively, indicating synergistic adverse effects on pulmonary edema.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia↗
PubMed1995

Changing heat and moisture exchangers every 48 hours rather than 24 hours does not affect their efficacy and the incidence of nosocomial pneumonia.

Heat and moisture exchangers (HME) (Dar-Hygrobac II, Peters) can safely be used every 24 h for long-term mechanical ventilation and provide a cost-saving alternative to heated humidifiers. We have prospectively determined whether changing HMEs every 48 h only affects their clinical and bacteriological efficiency in a series of consecutive nonselected ICU patients requiring long-term mechanical ventilation. Two consecutive periods were compared. During period 1, HMEs were replaced every day; during period 2, they were changed every 48 h. Patients from the two periods were similar in terms of age and indication for and overall duration of MV (10 +/- 8.6 versus 10 +/- 9 d, p = 0.9). Minute ventilation and maximum values for peak airway pressure were identical during the two periods. These values were also identical after 1 and 2 d of HME use during period 2, indicating that HME resistance was not increased by prolonged use. Obstruction of the tracheal tube occurred only once in a period 1 patient. The results of quantitative cultures indicate that the maximum and mean levels of bacterial colonization during the two periods were similar for the pharynx, trachea, Y-connector, patient, and ventilator side of the HME. More importantly, the incidence of nosocomial pneumonia was similar during the two periods (6/61 versus 8/68, p = 0.7). Thus, prolonged HME use is safe and provides a substantial reduction in the cost of mechanical ventilation.

Adult↗
PubMed1995

Mechanical ventilation with heated humidifiers or heat and moisture exchangers: effects on patient colonization and incidence of nosocomial pneumonia.

The contribution of ventilator circuit bacterial contamination to the occurrence of ventilator-associated pneumonia remains controversial. In a previous study, we found that the incidence of pneumonia was identical with ventilator circuit changes every 48 h and with no ventilator circuit changes. The present study prospectively assessed whether keeping ventilator circuits clean with a heat and moisture exchanger exhibiting antimicrobial barrier properties affects patient colonization and the incidence of nosocomial pneumonia in patients receiving mechanical ventilation for more than 48 h. Consecutive patients were randomly allocated to humidification with either a heat and moisture exchanger (Group 1, n = 61) or a heated humidifier (Group 2, n = 70). In both groups, no circuit changes were performed throughout ventilatory support. Duration of mechanical ventilation was identical in both groups (10 +/- 8.6 d (range: 2 to 47) in Group 1 and 12.5 +/- 14.2 d [range: 2 to 85] in Group 2). The incidence of pneumonia (positive quantitative culture of protected brush specimen) was similar in both groups (6/61 and 8/70 in Groups 1 and 2, respectively; p = 0.8), as was duration of ventilation prior to pneumonia (9 +/- 5.9 versus 8.2 +/- 5.7 d; p = 0.8). Ventilator tubing contamination was considerably reduced with the use of a heat and moisture exchanger. In contrast, bacterial colonization of the pharynx and trachea was identical in both groups. These results suggest that circuit colonization plays little or no role in the occurrence of ventilator-associated pneumonia, provided usual maintenance precautions are applied.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Spontaneous pneumothorax. Comparison of thoracic drainage vs immediate or delayed needle aspiration.

In the first part of this study, 61 patients admitted for the first episode or the first recurrence of a spontaneous pneumothorax (SP) were randomly treated with thoracic drainage (TD; 28 patients) or with simple needle aspiration (NA; 33 patients). Success rate of therapy was significantly higher with TD than with NA (93%, CI 84 to 100 vs 67%, CI 51 to 83; p = 0.01). Hospital stay was similar between the two groups (7 +/- 4.6 vs 7 +/- 5.6 days), mainly because NA was delayed by 72 h in 26 patients. Recurrence rates at 3 months were 29% (CI 11 to 47%) after TD, and 14% (CI 0 to 29%) after NA (p > 0.20, NS). In the second part of the study, an additional population of 35 patients was treated by immediate NA, with a success rate of 68.5% (CI 53.5 to 83.5%), and a recurrence rate at 3 months of 30% (CI 10 to 50%). Taken together, our results indicate that NA may be proposed as a first-line treatment of SP, with a successful result in two thirds of patients and recurrence in one fifth of patients. In patients who do not heal with NA, a combined risk of TD failure and short-term recurrence of 50% may be an incentive for undelayed surgical procedures.

Adolescent↗
PubMed1995

[Deleterious effects of mechanical ventilation on the lower lung].

Mechanical ventilation may have adverse effects on the lung. The appearance of extra-alveolar air, either as a pneumothorax or as subcutaneous emphysema along with other manifestations, is a complication of barotrauma which has been known for a long time. Recent experimental studies have clearly shown that mechanical ventilation can also lead to alterations in the blood gas barrier. Mechanical ventilation with high inflation pressure and elevated tidal volumes induces pulmonary oedema; the genesis of which results principally from anomalies of alveolar capillary permeability. These anomalies are made as a result of pulmonary distension and not as a result of elevated pressures in the airways, thus justifying the term "volume traumatism". The existence of previous acute pulmonary injury considerably worsens the deleterious pulmonary effect of mechanical ventilation. Although the direct clinical implications of these experimental studies are difficult to confirm, these latter have nevertheless lead to profound changes in ventilatory strategy during the course of acute pulmonary disease such as the adult respiratory distress syndrome.

Adult↗
PubMed1994

A placebo-controlled trial of trihexyphenidyl in unmedicated patients with schizophrenia.

Seventeen patients with schizophrenia who had been free of medication for at least 2 months entered a placebo-controlled, random-order crossover trial of 5 mg of trihexyphenidyl twice daily for 4 weeks. Ten patients completed trials of both drug and placebo. Ratings of anticholinergic symptoms and of feeling the effects of the drug, controlled for order effects, were significantly higher at week 4 of the trihexyphenidyl trial than at week 4 of the placebo trial. Measures of psychosis, negative symptoms, depression, and liking the drug did not differ between trihexyphenidyl and placebo trials.

Adult↗
PubMed1994

Fluoxetine in posttraumatic stress disorder.

BACKGROUND: This study was designed to establish the efficacy of the serotonin reuptake blocker fluoxetine in the treatment of posttraumatic stress disorder (PTSD). METHOD: 64 subjects (22 women and 42 men; 31 veterans and 33 nonveterans) with PTSD entered a 5-week randomized double-blind trial comparing fluoxetine (N = 33) and placebo (N = 31). RESULTS: By Week 5 fluoxetine, but not placebo, significantly reduced overall PTSD symptomatology, as assessed by the Clinician-Administered PTSD Scale (CAPS) score. Changes were most marked in the arousal and numbing symptom subcategories. Non-VA patients responded much better than VA patients. Fluoxetine was an effective antidepressant independent of its effects on PTSD. CONCLUSION: Fluoxetine is an effective pharmacotherapeutic agent for treating PTSD and its associated features, particularly in patients without chronic treatment histories.

Adolescent↗
PubMed1994

Platelet-activating factor receptor antagonist BN 52021 in the treatment of severe sepsis: a randomized, double-blind, placebo-controlled, multicenter clinical trial. BN 52021 Sepsis Study Group.

OBJECTIVE: To evaluate the safety and efficacy of a natural platelet-activating factor receptor antagonist, BN 52021 (Ginkgolide B), in the treatment of patients with sepsis syndrome. DESIGN: Prospective, randomized, placebo-controlled, double-blind, phase III, multicenter clinical trial. SETTING: Twenty-one academic medical center intensive care units in France. PATIENTS: Two hundred sixty-two patients with sepsis syndrome who received standard supportive care and antimicrobial therapy, in addition to the administration of platelet-activating factor receptor antagonist or placebo. INTERVENTIONS: Patients received either a 120-mg dose of platelet-activating factor receptor antagonist intravenously every 12 hrs over a 4-day period or placebo. MAIN OUTCOME MEASUREMENTS: All patients were evaluated for 28-day, all-cause mortality. RESULTS: The 28-day mortality rate was 51% for the placebo group and 42% for the platelet-activating factor receptor antagonist group (p = .17). However, the efficacy of platelet-activating factor receptor antagonist was significantly greater in patients with Gram-negative sepsis (test for interaction, p = .03). In a separate analysis of patients with and without Gram-negative sepsis, the 28-day mortality rate was 57% for the patients receiving placebo (30 deaths of 53 patients) and 33% for patients receiving platelet-activating factor receptor antagonist (22 deaths of 67 patients; p = .01). Platelet-activating factor receptor antagonist also significantly (p = .01) reduced the mortality rate among patients with Gram-negative sepsis who were in shock at entry into the study (mortality rate was 65% for placebo vs. 37% for platelet-activating factor receptor antagonist) and among patients > 60 yrs of age (mortality rate was 74% for placebo vs. 31% for platelet-activating factor receptor antagonist). A Cox proportional-hazards model identified five independent prognostic factors: a) adequacy of antibiotic therapy; b) severity of illness; c) renal failure; d) hematologic failure; and e) hepatic failure at study entry. When the Gram-negative sepsis population was stratified by age and these five prognostic factors were controlled for, the relative risk of death of the platelet-activating factor receptor antagonist group was 0.61 (0.34 to 1.08, 95% confidence interval; p = .09). This risk corresponds with an adjusted reduction in mortality rate of 39% for patients receiving platelet-activating factor receptor antagonist. No differences in mortality rates were found between the placebo and the platelet-activating factor receptor antagonist groups in the absence of Gram-negative sepsis. There were no differences in adverse events between the placebo and the treated groups. CONCLUSION: The studied platelet-activating factor receptor antagonist (BN 52021) seems to be a safe and promising treatment for patients with severe Gram-negative sepsis.

APACHE↗
PubMed1993

Is penicillin G an adequate initial treatment for aspiration pneumonia? A prospective evaluation using a protected specimen brush and quantitative cultures.

OBJECTIVE: To evaluate the bacteriology of early aspiration pneumonia using a protected specimen brush and quantitative culture techniques, and whether penicillin G is adequate as initial treatment pending culture results. PATIENTS AND METHODS: 52 patients (of which 45 required mechanical ventilation) meeting usual clinical criteria for aspiration pneumonia were prospectively included. On admission, patients were given intravenous penicillin G and a protected specimen brush was performed < or = 48 h after. RESULTS: Cultures of the brush were negative (< 10(3) CFU/ml) in 33 patients (1 had blood cultures positive with S. pneumoniae) and positive (> or = 10(3) CFU/ml) for S. pneumoniae in 2 patients. Seventeen patients had a positive culture (> or = 10(3) CFU/ml) for at least one penicillin G resistant microorganism, with a total of 20 organisms (S. aureus: 6; H. influenzae: 2; Enterobacteriaceae: 8; P. aeruginosa: 3; C. albicans: 1). In 4 of these patients, a penicillin-sensitive pathogen was also recovered in significant concentrations (S. pneumoniae: 2; Streptococcus sp.: 2). These 17 patients with a resistant pathogen did not differ from the 35 other patients with respect to need for ventilatory support and mortality rate. By contrast, they were older (61.1 +/- 21.9 vs. 42.9 +/- 18.8 years; p < 0.005) and required longer mechanical ventilation (6.1 +/- 4.6 vs. 3.5 +/- 2.7 days; p < 0.03) and hospitalization (11.2 +/- 8.8 vs. 6.7 +/- 4.7 days; p < 0.02). Of 17 patients 12 with penicillin G resistant organisms versus 0/35 without, were in-hospital patients and/or had a digestive disorder (p < 0.001). CONCLUSION: The broad range of offending organisms seen in early aspiration pneumonia precludes use of any single empiric regimen, making protected specimen brush mandatory in many patients. Nevertheless, the involvement of S.pneumoniae in a notable proportion of our patients suggests that routine penicillin prophylaxis after early aspiration (at least in most patients with community-acquired aspiration) is warranted given the potential severity of pneumococcal sepsis in such patients.

Adult↗
PubMed1993

Clinical significance of borderline quantitative protected brush specimen culture results.

In patients with clinical suspicion of pneumonia, quantitative cultures of protected brushing specimens (PBS) yielding > or = 10(3) CFU/ml of at least one microorganism have been found useful for differentiating airway colonization and lung infection, especially in mechanically ventilated patients. The amount of secretions collected by protected catheter brushing is small and difficult to determine accurately. Thus, the clinical significance of PBS cultures yielding organisms in concentrations > or = 10(2) but < 10(3) CFU/ml, in the absence of active antimicrobial treatment, is unknown. The 34 consecutive results of PBS cultures yielding organisms in concentrations > or = 10(2) but < 10(3) CFU/ml in 30 patients under mechanical ventilation or weaned for < or = 4 days were prospectively studied. No patients were receiving agents active on the organism recovered. In 5 cases, the diagnosis of pneumonia was ruled out by recovery without treatment (n = 4) or negative postmortem lung cultures (n = 1). A second PBS was cultured in 29 episodes (2.7 +/- 1.8 days after the first PBS). In 12 instances (Group 1), cultures of the second PBS yielded > or = 10(3) CFU/ml of the same organism as that found in the first PBS (S. pneumoniae, 1; S. aureus, 1; H. influenzae, 1; E. coli, 1; P. aeruginosa, 4; and A. baumannii, 4), and these patients were therefore treated with appropriate antibiotics. A total of 17 patients had a negative repeat PBS culture (no growth or trivial concentrations) and were considered free of pneumonia and given no antibiotic treatment for this episode.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteria↗
PubMed1993

Role of tidal volume, FRC, and end-inspiratory volume in the development of pulmonary edema following mechanical ventilation.

Mechanical ventilation with high peak inspiratory pressure and large tidal volume (VT) produces permeability pulmonary edema. Whether it is mean or peak inspiratory pressure (i.e., mean or end-inspiratory volume) that is the major determinant of ventilation-induced lung injury is unsettled. Rats were ventilated with increasing tidal volumes starting from different degrees of FRC that were set by increasing end-expiratory pressure during positive-pressure ventilation. Pulmonary edema was assessed by the measurement of extravascular lung water content. The importance of permeability alterations was evaluated by measurement of dry lung weight and determination of albumin distribution space. Pulmonary edema with permeability alterations occurred regardless of the value of positive end-expiratory pressure (PEEP), provided the increase in VT was large enough. Similarly, edema occurred even during normal VT ventilation provided the increase in PEEP was large enough. Furthermore, moderate increases in VT or PEEP that were innocuous when applied alone, produced edema when combined. The effect of PEEP was not the consequence of raised airway pressure but of the increase in FRC since similar observations were made in animals ventilated with negative inspiratory pressure. However, although permeability alterations were similar, edema was less marked in animals ventilated with PEEP than in those ventilated with zero end-expiratory pressure (ZEEP) with the same end-inspiratory pressure. This "beneficial" effect of PEEP was probably the consequence of hemodynamic alterations. Indeed, infusion of dopamine to correct the drop in systemic arterial pressure that occurred during PEEP ventilation resulted in a significant increase in pulmonary edema. In conclusion, rather than VT or FRC value, the end-inspiratory volume is probably the main determinant of ventilation-induced edema. Hemodynamic status plays an important role in modulating the amount of edema during lung overinflation but does not fundamentally modify the characteristics of this edema which is consistently associated with major permeability alterations. These results may be relevant for ventilatory strategies during acute respiratory failure.

Albumins↗
PubMed1993

Prospective evaluation of the incidence of bacteremia after protected specimen brushing in ICU patients with and without pneumonia.

To test the hypothesis that the use of protected specimen brushing (PSB) via flexible bronchoscopy does not predispose to bacteremia in ICU patients, we prospectively performed aerobic and anaerobic blood cultures immediately following bronchoscopy with PSB. A total of 123 episodes in 68 consecutive patients with suspected pneumonia were analyzed. Blood cultures were negative in 110 cases (89 percent) and positive in 13 cases (11 percent) (p < 0.001). Twelve of these 13 patients with positive blood cultures had quantitative PSB specimen cultures showing nonsignificant growth (< 10(3) CFU/ml). In nine patients, the bacteria recovered from blood cultures (coagulase-negative staphylococci or sarcina) were considered nonpathogenic according to conventional criteria. Blood cultures grew a Staphylococcus aureus in two patients with previously documented staphylococcal septicemia. In one patient with no identifiable site of infection, the blood culture yielded Enterococcus faecalis. The only patient with both a positive blood culture and PSB culture results indicating pneumonia had different organisms recovered from the two samples. Blood cultures taken after PSB in the 17 other episodes of pneumonia (PSB specimen cultures > or = 10(3) CFU/ml) were negative. At the time of brushing and blood sampling for culture, none of these patients was receiving antibiotics active on the organisms found. In conclusion, the incidence of bacteremia after PSB in ICU patients seems very low even in patients with documented pneumonia. Substantial savings would result from not performing routine blood cultures after PSB.

Aged↗