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V de Larminat

Publications and source records attributed to V de Larminat.

6 recordsLinked to original sources

Role of prostaglandins and nitric oxide on halothane-induced arteriolar dilatation in rat diaphragm.

The effects of anaesthetics on the microcirculation of the diaphragm are incompletely understood. Therefore, we assessed by in vivo intravital microscopy in rats the action of halothane on diaphragmatic arteriolar diameter and the role of nitric oxide and prostaglandins on halothane-induced diaphragmatic arteriolar diameter. We studied 54 rats anaesthetized with thiopentone. Dose-response curves to topically applied Krebs' solution saturated with halothane at increasing concentrations of 0%, 1%, 3% and 5% were carried out in the presence of an inhibitor of nitric oxide synthesis (N omega-nitro-L-arginine (LNA), 300 mumol litre-1) or inhibitors of prostaglandin synthesis (mefenamic acid 20 mumol litre-1 or indomethacin 20 mol litre-1) or in the absence of any inhibitor. We found dose-dependent arteriolar dilatation which was abolished by mefenamic acid and indomethacin. In contrast, the effect of halothane was not modified by LNA. These data demonstrated that halothane-induced arteriolar dilatation in the diaphragm of the rat was mediated by prostaglandins but not by nitric oxide.

Anesthetics, Inhalation↗

Alteration in swallowing reflex after extubation in intensive care unit patients.

OBJECTIVES: To assess the swallowing reflex after prolonged endotracheal intubation and to assess the influence of age and duration of intubation on this reflex. DESIGN: Prospective, observational, clinical study. SETTING: The intensive care unit of a university teaching hospital. PATIENTS: The swallowing reflex was studied after extubation in 34 patients and compared with the deglutition in 30 nonintubated patients with a nasogastric tube and 15 nonintubated patients without a nasogastric tube. INTERVENTIONS: Four volumes of normal saline (0.25, 0.50, 0.75, and 1 mL) were injected at the epipharynx level. Swallowing efficiency was assessed by the latency between instillation and the first swallow, as identified on a submental electromyogram. The tests were performed immediately (day 0), and at 1 (day 1), 2 (day 2), and 7 (day 7) days after extubation in the intubated group. Nonintubated patients were tested once. MEASUREMENTS AND MAIN RESULTS: On day 0, the latency was increased for each bolus in the extubated group when compared with the control groups. Significant shortening of latency after 0.50, 0.75, and 1 mL injections of normal saline occurred on days 1 and 2 when compared with day 0, whereas no change was observed after 0.25 mL of normal saline was injected. On day 7, a significant improvement was observed, regardless of the volume injected. There was no correlation between swallowing latency and either the age of the patients or the duration of endotracheal intubation. CONCLUSIONS: These data indicate that prolonged endotracheal intubation impairs the swallowing reflex, with improvement within 1 wk. This phenomenon could contribute to microinhalations and aspiration pneumonia after extubation.

Aged↗

[Changes in the deglutition reflex during the perioperative period].

The swallowing reflex is one of the major mechanisms protecting the lungs against aspiration of foreign material. Its complex time course requires a perfect coordination with ventilation, as the aerodigestive crossroads are common for both functions. Physiological factors as ageing, as well as mechanical and pharmacological agents, may contribute to swallowing reflex alterations. Moreover, endotracheal intubation and most anaesthetic agents may impair the swallowing function and favour the occurrence of aspiration. This review discusses the normal swallowing process and its alterations by agents currently used in anaesthesia. Furthermore, the effect of intubation as well as changes related to co-existing diseases are considered.

Aged↗

Penetration of piperacillin-tazobactam into bronchial secretions after multiple doses to intensive care patients.

The penetration of piperacillin-tazobactam in eight mechanically ventilated intensive care patients (age, 56.0 +/- 12.2 years, and weight, 76.5 +/- 15.2 kg [means +/- standard deviations]) with bacterial pneumonia was investigated. They were given intravenous doses of piperacillin (4 g) and tazobactam (0.5 g) as 30-min infusions every 6 h. The kinetic study was performed after the fourth dose on day 2 of treatment. Samples of blood and bronchial secretions (BS) were collected before the fourth dosing and 0.5, 1, 2, 4, and 6 h after the end of infusion. Drug concentrations in both sera and BS were measured by high-performance liquid chromatography. Concentrations (in micrograms per milliliter) in serum were 184.80 +/- 63.03 and 40.03 +/- 30.79 for piperacillin and 23.05 +/- 7.53 and 4.86 +/- 4.54 for tazobactam at 0.5 and 6 h, respectively, after the end of infusion. The corresponding concentrations (in micrograms per milliliter) in BS were 29.33 +/- 25.08 and 20.25 +/- 19.11 for piperacillin and 6.86 +/- 4.25 and 4.25 +/- 2.78 for tazobactam. The percentages for the extent of penetration of piperacillin and tazobactam, as defined by the BS/serum area under the curve ratio, were 35.70 and 78.42%, respectively. These data indicate good penetration of both piperacillin and tazobactam into BS. The concentrations of tazobactam in BS are persistent and high enough to exceed the values found to be effective in vitro against the tazobactam-susceptible beta-lactamases produced by the most important pathogens responsible for nosocomial pneumonia.

Adult↗

[Impairment of deglutition reflex after prolonged intubation].

This study was designed to assess the swallowing reflex after an endotracheal intubation of more than 24 h, as well as the influence of age and duration of intubation on swallowing. Twenty patients (aged 58 +/- 17 years) who had been intubated for more than 24 h were compared with fifteen others (63.1 +/- 16.7 years), who had never been intubated. All had a nasogastric tube. Swallowing was assessed after administration of 0.25, 0.5, 0.75 and 1 ml volumes of normal saline, in a random sequence, into the epipharynx through a thin catheter passing through the nostril after extubation (E0), and then at 1 (E1), 8 (E8), 24 (E24) and 48 h (E48) in the extubated patients, and once in the control patients. Swallowing responses were identified by an electromyogram of the floor of the oral cavity. The efficiency of the swallowing reflex was assessed by the delay between instillation and the first swallowing response obtained, and the number of swallows recorded during the first 15 seconds following each injection. There was a significant increase in swallowing delay in intubated patients for volumes less than 1 ml during the first three measurements. Recovery occurred for 0.5 and 0.75 ml at E24 and E48, when compared with the control group. However, delay remained increased throughout the study for 0.25 ml. The number of swallows was the same in both groups for each volume tested. There was no correlation between increased delay and age or duration of intubation. These data confirmed that prolonged endotracheal intubation impairs the swallowing reflex.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗