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S Duperret

Publications and source records attributed to S Duperret.

At least 19 recordsLinked to original sources
PubMed2006

Effects of increased intra-abdominal pressure on central circulation.

BACKGROUND: In an experimental model we investigated the effects of a gradual increase in intra-abdominal pressure (IAP) on the central circulation. METHODS: Seven pigs were anaesthetized, mechanically ventilated and instrumented. IAP was gradually increased by 5 mm Hg up to 30 mm Hg by abdominal banding in normovolaemic animals, and then they were made hypovolaemic after blood withdrawal. Right atrial pressure (RAP) and left ventricular end-diastolic pressure (LVEDP) at each step and aortic, femoral and inferior vena cava blood flows were measured. Left ventricular end-diastolic area (LVEDA) was determined using epicardial echocardiography. RESULTS: Cardiac output maintained at mild IAP was reduced to 76 (24)% of the initial value at 30 mm Hg IAP [mean (sd)] in normovolaemic animals, and 72 (22)% (P<0.001) in hypovolaemic animals. In normovolaemic animals the LVEDA and LVEDP were significantly increased at an IAP of 10 and 15 mm Hg by 26 (24)% and 38 (23)%, respectively. At these IAP values, the difference between the RAP and IAP was positive. When this gradient became negative, that is beyond 15 mm Hg in normovolaemia and for all IAP values in hypovolaemic animals, the LVEDA declined, reaching 78 (16)% and 62 (22)% (P<0.05) of the initial values in normovolaemic and hypovolaemic groups at the highest IAP value. CONCLUSIONS: These results showed that a gradual increase in IAP led to a redistribution of abdominal blood volume towards the thoracic compartment, at IAP lower than 15 mm Hg in normovolaemia, and at its expense at higher values of IAP. In hypovolaemia there was no thoracic compartment gain. Whereas the absolute or transmural RAPs were not informative of the direction of this blood shift, an RAP greater than IAP was associated with an intrathoracic compartment gain.

Abdomen↗
PubMed2006

Cardiac lesions induced by 5-fluorouracil in the rabbit.

Cardiotoxicity is a rare, but well-recognized complication of treatments with the anti-cancer drug 5-fluorouracil (5FU). The underlying mechanism, however, is not fully elucidated. A spasm of the coronary arteries is often considered to be the leading cause of myocardial ischemia and decreased contractility associated with 5FU. As spasm cannot account for all reported adverse cardiac effects, the present study was undertaken to search for alternative mechanisms. Groups of six rabbits were given either a single intravenous dose of 50 mg/kg 5FU or four intravenous doses of 15 mg/kg 5FU at 7-day intervals. A third group served as control. The heart was removed shortly after death or scheduled sacrifice of the animals, to perform macroscopic and microscopic examinations of the heart and to evidence apoptosis by the TUNEL method. Following a single dose of 50 mg/kg 5FU, all animals rapidly developed a massive hemorrhagic myocardial infarct with spasms of the proximal coronary arteries. Repeated infusions of 15 mg/kg 5FU induced left ventricular hypertrophy, foci of myocardial necrosis, thickening of intra-myocardial arterioles, and disseminated apoptosis in myocardial cells of the epicardium, as well as endothelial cells of the distal coronary arteries. These results indicate that a spasm of the coronary arteries is not the only mechanism of 5FU cardiotoxicity, and that apoptosis of myocardial and endothelial cells can result in inflammatory lesions mimicking toxic myocarditis.

Animals↗
PubMed2004

Amniotic fluid embolism during caesarean section.

Amniotic fluid embolism occurs rarely but is a leading cause of maternal mortality. A high index of clinical suspicion is necessary to make an early diagnosis to reduce morbidity and mortality. We report a non-fatal case of amniotic fluid embolism occurring during a caesarean section, with special emphasis on the mode of development and diagnosis. The initial presentation of this syndrome was a coagulopathy, followed by the usual complications of massive bleeding. Although non-specific, the diagnosis of amniotic fluid embolism was supported by the observation of amniotic fluid in the central venous blood as well as in the broncho-alveolar fluid.

Adult↗
PubMed2003

[Risk factors for amoxicillin-clavulanate-resistant Escherichia coli in ICU patients].

OBJECTIVE: To determine risk factors of infections with amoxicillin-clavulanate-resistant Escherichia coli in ICU patients. STUDY DESIGN: Prospective, consecutive sample survey study. PATIENTS: A consecutive series of 133 patients from whom culture results were positive for E. coli during their ICU stay. METHODS: Risk factors analysed included demographics, comorbid conditions, and antimicrobial drug exposure. Univariate and multivariate analysis were performed. RESULTS: Multivariate logistic regression analysis identified only one significant independent factor associated with the emergence of amoxicillin-clavulanate-resistant E. coli: prior use of amoxicillin (odds ratio: 5.45). CONCLUSION: Clinicians should avoid administering amoxicillin-clavulanate as empiric therapy for possible E. coli infection in patients that have recently been treated with amoxicillin.

Adult↗
PubMed2002

[ARDS as an unusual presentation of bronchiolitis obliterans organizing pneumonia].

We report the case of a 46-year-old patient with liver transplantation who developed an acute respiratory distress syndrome (ARDS). The commonly associated clinical disorders, those associated with direct injury to the lung and those that cause indirect lung injury in the setting of a systemic process, were not responsible for the clinical picture. Finally, because of progressive clinical deterioration, an open-lung biopsy was performed and revealed a bronchiolitis obliterans with organizing pneumonia (BOOP). Physicians should be aware of this rare aetiology of ARDS.

Adult↗
PubMed1999

Cervical necrotizing fasciitis: 10 years' experience at a single institution.

OBJECTIVE: To evaluate clinical and microbiologic characteristics, modalities of treatment and outcome of patients with cervical necrotizing fasciitis admitted to our institution. DESIGN: Retrospective clinical investigation. PATIENTS AND METHODS: We reviewed the charts of 20 consecutive patients hospitalized in our Intensive Care Unit between January 1987 and June 1998 with the diagnosis of cervical necrotizing fasciitis. RESULTS: All the patients required mechanical ventilation. Four of them had mediastinal involvement. The organisms most commonly implicated included Streptococcus, Prevotella, and Peptostreptococcus species. Patients with adequate surgery had a better outcome than those with inadequate surgical procedures. Because no evidence-based recommendations exist in the field of head and neck infections, hyperbaric oxygen was not used as adjunctive therapy. Of the 20 patients, 3 (15 %) died. CONCLUSION: The main finding of this study is that prompt, rather than delayed, surgical débridement correlates with a decrease in morbidity and mortality. However, no definite conclusion is justified due to the relatively small number of patients. Immediate radical débridement, and early redébridement if needed, appropriate antibiotics and intensive care support are critical in controlling these life-threatening infections.

Adult↗
PubMed1998

[The good use of antibiotics in intensive care: results of a program for rationalization of prescriptions].

OBJECTIVE: To assess the impact of an antibiotic prescribing programme in a intensive therapy unit. TYPE OF STUDY: Prospective comparative study. METHODS: We compared antibiotic prescriptions and bacterial susceptibility to antimicrobial agents before and after introduction of a programme focusing on injection control and therapeutic indications. RESULTS: The introduction of the programme resulted in a major decrease in antibiotic administration. Moreover, the susceptibility of Pseudomonas aeruginosa to ticarcillin increased from 40 to 68%, and susceptibility of Staphylococcus aureus to methicillin increased from 55 to 73%. CONCLUSIONS: Antibiotic control policies must be considered integral to any effort to decrease resistance and cost of therapy with antibiotics.

Anti-Bacterial Agents↗
PubMed1998

Time course evolution of ventilatory responses to inspiratory unloading in patients.

Inspiratory muscle unloading decreases ventilatory drive. In this study, we examined the time course of this effect in patients with chronic obstructive pulmonary disease receiving two modes of ventilatory support: pressure support ventilation (PSV), during which each cycle was assisted, and biphasic positive airway pressure (BIPAP), set up in such a manner that one spontaneous breath took place between two consecutive pressure-assisted breaths. The first breath following the switch from spontaneous breathing to PSV was associated with an increase in tidal volume (VT) and a drop in mean transdiaphragmatic pressure (mean Pdi) and inspiratory work (WI) performed per liter but with unchanged values of esophageal occlusion pressure at 100 ms (Pes 0.1), diaphragmatic electrical activity (EMGdi), and WI performed by breath. The same phenomena were observed for the assisted breath of BIPAP as compared with the preceding spontaneous breath. During the subsequent breaths of PSV, Pes 0.1, EMGdi, and WI performed per breath decreased progressively up to the sixth to eighth breaths, and VT returned to pre-PSV values. We conclude that in patients with chronic obstructive pulmonary disease the decrease in ventilatory drive associated with PSV takes place from the first breath onwards but requires six to eight breaths to be fully achieved. During BIPAP, as a consequence of the kinetics of the PSV-induced downregulation of ventilatory drive, assisted breaths following spontaneous breaths are characterized by an enhanced inspiratory efficiency.

Aged↗
PubMed1997

Haemodynamic changes induced by two I:E ratios: a transoesophageal echocardiographic study.

PURPOSE: To assess the effects of controlled ventilation with two I:E ratios on haemodynamic and left ventricular function in mechanically ventilated patients with moderate to severe respiratory disease, using fluctuation of the arterial pressure waveform and the changes in left ventricular areas obtained by transoesophageal echocardiography. METHODS: Nine patients had their lungs ventilated using volume controlled ventilation with two I:E ratios 1:3 and 1:1). Respiratory rate was adjusted so that six cardiac beats occurred during a respiratory cycle. Systolic blood pressure variation (SBPV), left ventricular area variations measured by TEE and haemodynamic variables measured by PA catheter were compared. RESULTS: When compared with I:E (1:3), I:E (1:1) decreased end diastolic area (EDA) throughout the respiratory cycle from 3% to 8% (P < 0.01) and increased SBPV from 6 +/- 1 to 11 +/- 1 mmHg (P < 0.01). In four patients, SBPV was > 12 mmHg with I:E 1:1. Conversely, SBPV was < 10 mmHg in all patients with I:E 1:3. With I:E (1:1), EDA decreased up to 7% during expiration (P < 0.01). The ejection fraction area remained stable for both ventilatory patterns and throughout the ventilatory cycle for a given I:E. The usual invasive haemodynamic variables were unchanged throughout the study, as was PaO2/FIO2. CONCLUSION: In this setting, EDA and SBPV allow beat-to-beat evaluation of left ventricular preload during change of I:E ratio. Switch from I:E 1:3 to 1:1 may be used as a rapid, safe and reversible test to estimate intravascular volume status assessed by changes in SBPV or EDA.

Adult↗
PubMed1997

Major cellulitis following percutaneous tracheostomy.

Percutaneous tracheostomy, a technique that can be performed at the bedside in the intensive care unit (ICU), is increasingly used for critically ill ventilator-dependent patients. Based on many clinical studies, this procedure appears to be simple, rapid and safer than conventional surgical tracheostomy. This technique produces a stoma tissue tract that fits snugly around the cannula, and this could explain the low incidence of infective complications. However, we report two cases of life-threatening cellulitis, a serious complication that has rarely been reported previously.

Adult↗
PubMed1997

Comparison of transesophageal and transthoracic contrast echocardiography for detection of an intrapulmonary shunt in liver disease.

STUDY OBJECTIVES: Contrast transthoracic echocardiography (TTE) is currently used to identify intrapulmonary shunt (IPS) in patients with end-stage liver disease. The aim of this study was to compare the use of contrast TTE and transesophageal echocardiography (TEE) in detecting IPS. DESIGN: Thirty-seven consecutive outpatients with severe liver disease awaiting liver transplantation underwent contrast TEE and TTE. The IPS was assessed semiquantitatively in four grades with TEE and as positive or negative with TTE. SETTING: ICU. INTERVENTIONS: Patients underwent contrast TEE after pharyngeal anesthesia alone followed by contrast TTE. Contrast echocardiography was performed with a modified fluid gelatin solution. RESULTS: Overall detection rate of an IPS was 51% with TEE and 32% with TTE (p < 0.001). Four patients had an IPS detected with TEE but not with TTE. Quality of imaging was poor in 22% with TTE and 0% with TEE (p < 0.001). A PaO2 < 80 mm Hg or a dyspnea was associated with an IPS in 56% and 50% of patients with TEE and in 33% and 25% with TTE, respectively. CONCLUSION: Contrast-enhanced TEE is superior to TTE for detecting an IPS in patients with severe liver disease awaiting liver transplantation. The use of gelatin contrast solution allows an early detection of IPS. Because of the high sensitivity of TEE, all patients suspected of hepatopulmonary syndrome should undergo TEE in search of an IPS if TTE is normal.

Arteriovenous Fistula↗