Search PubMed⌕ Search

Biomedical subjects

F Clergue

Publications and source records attributed to F Clergue.

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

Evaluation by polymerase chain reaction of cytomegalovirus reactivation in intensive care patients under mechanical ventilation.

OBJECTIVE: The study was undertaken to determine if critically ill patients under mechanical ventilation could reactivate latent cytomegalovirus (CMV) in either lung or blood. DESIGN: Prospective study in critically ill patients was performed in a multidisciplinary intensive care unit in a university hospital. PATIENTS: 23 non-immunocompromised, mechanically ventilated patients who were anti-CMV immunoglobulin G-positive. Ten immunocompromised patients with active CMV infection and 16 asymptomatic CMV seropositive non-immunocompromised patients constituted the positive and negative control groups. MEASUREMENTS AND RESULTS: The presence of CMV in blood and bronchoalveolar lavage (BAL) was evaluated by both viral cultures and polymerase chain reaction (PCR). Thirty-seven blood and 22 BAL samples were investigated. Sequential samples were evaluated in 8 patients. For PCR, a 290 bp fragment in the first exon of the immediate early 1 gene was amplified. In order to exclude inhibitors of PCR amplification, a 268 bp fragment of the beta-globin gene was concurrently amplified in all samples. Viral cultures of blood and BAL were negative in all 23 non-immunocompromised, mechanically ventilated patients. Moreover, no CMV DNA could be amplified in blood BAL samples, whereas a beta-globin amplification was observed in all samples. CONCLUSION: In a series of 23 critically ill patients under mechanical ventilation who were seropositive for CMV, no reactivation of CMV in blood or lung was demonstrated.

Adult↗
PubMed1996

[Evaluation of direct theoretical cost of passage in anesthesia recovery room].

OBJECTIVE: To assess the direct cost of a stay in a postanaesthesia care unit (PACU). STUDY DESIGN: Standard cost study based on information gathered from staff and suppliers in accordance with government regulations and recommendations. Results reviewed by a group of anaesthesists. TYPE OF PACU: PACU working in ideal conditions with optimal safety conditions for and accommodation surgical patients). METHOD: Estimation of three cost components: 1) depreciation and maintenance costs of equipment, 2) physician and other staff wages, and 3) variable costs such as drugs and disposable devices. We computed an annual budget for three PACU which was defined according to size (4, 8 or 12 beds) and working hours. RESULTS: Fixed annual costs (staff and equipment) were 1,134,938 FF for a 4 bed room: 3,820,339 FF for an 8 bed room: and 6,481,792 FF for a 12 bed room. Variable costs per stay were 75,43 FF. The cost of a stay in an 8 bed PACU based on a rate of 3,500 stays per year therefore was 1,167 FF (87.0% for staff, 6.6% for equipment, 6.4% for variable costs).

Cost of Illness↗
PubMed1995

[Ventilators for anesthesia. Models available in France. Criteria for choice].

This update article discusses the criteria for the choice of an anaesthetic machine and provides a short analysis of the main components of the models commercialized in France in 1994. The following items are considered: the design of the machine, the fresh gas delivery system, the anaesthesia breathing system(s), the ventilator and the waste gas scavenging system, the monitors associated with the machine and other criteria such as facility of learning to run the machine and of its daily use, ease of "in-house" maintenance and quality of after-sales service, cost of the machine and of its use (driving gas, disposable equipment).

Anesthesia, Inhalation↗
PubMed1995

Inferences about respiratory muscle use after cardiac surgery from compartmental volume and pressure measurements.

BACKGROUND: After upper abdominal surgery, patients have been observed to have alterations in respiratory movements of the rib cage and abdomen and respiratory shifts in pleural and abdominal pressure that suggest dysfunction of the diaphragm. The validity of making such deductions about diaphragm function from these observations is open to discussion. METHODS: In eight adult patients, American Society of Anesthesiologists physical status 2, scheduled for elective cardiac surgery, we measured respiratory rate, tidal volume, rib cage and abdominal cross-section changes, and esophageal (Pes) and gastric (Pga) pressures preoperatively, 1 day postoperatively, and 5 days postoperatively. These data were analyzed in detail by following the variables through each respiratory cycle. RESULTS: Mean delta Pga/delta Pes decreased from 0.73 preoperatively to -0.56 1 day postoperatively and recovered to 0.47 5 days postoperatively. Plots of Pes against Pga and rib cage against abdominal expansion (Konno-Mead diagrams) were constructed. Six patients showed a postoperative pattern of breathing similar to that seen in patients who have undergone abdominal surgery: a decrease in the ratio of delta Pga/delta Pes and a shift toward rib cage expansion, with an increase in breathing rate and a decrease in tidal volume. This change was accomplished in most cases by the use of abdominal muscles in expiration with an increase in inspiratory intercostal muscle action without an increase in diaphragm activation, that is, a shift in the normal balance of respiratory muscle use in favor of muscles other than the diaphragm. A different ventilatory pattern was observed in the other two patients, consisting of minimal rib cage excursion and a large abdominal excursion. In these cases tidal volume was generated largely by contraction and relaxation of abdominal muscles with probable reduction in diaphragm activity. In addition, five patients exhibited positive changes in Pes at the end of inspiration that corresponded to closure of the upper airway, relaxation of inspiratory muscles, and subsequent opening of the airway with sudden exhalation, producing a grunt. CONCLUSIONS: Indirect measurements of respiratory muscle action based on pressure and chest wall motion are easier than are assessments based on implanted electromyogram electrodes and sonomicrometers that measure electric activity and muscle length, respectively, directly. Interpretation requires numerous assumptions and detailed analysis of phase relations among the variables. In patients after thoracic surgery, however, these measurements strongly point to a shift in the distribution of motor output toward muscles other than the diaphragm.

Abdominal Muscles↗
PubMed1994

[Pollution and retro-pollution by the distribution system of medical gases].

The anaesthetic machine, the recovery room or the ICU ventilator as well as any other simple oxygenation device can be accidentally supplied with a "wrong" gas, or a mixture of "wrong" and "true" gases, or a gas containing chemical impurities, as a result of one of the following causes: a) the source of the medical gas pipeline supply contains a "wrong" gas or impurities; b) the gas pipeline is polluted by a "wrong" gas or solvents, introduced during the installation or maintenance of the pipeline; c) the pipeline is polluted by a wrong gas at a point of inter-connection or cross-connection of two pipelines; d) supply of a "wrong" gas through wrong quick couplers connected to the pipeline; e) back flow of a gas in another pipeline supply through a defective gas mixer, which is today the most common cause of pipeline contamination or retropollution. It occurs with some types of mixers in case of absence or malfunction of non-return valves, associated with a pressure difference between the two gas lines. The means of prevention, recognition and emergency treatment of these events include: a) systematic removal of mixers and flowmeter-mixers from supplies when not in use; b) periodical checking of these devices for an accidental communication between the gases to be mixed; c) systematic use of an oxygen analyser for a continuous measurement of FIO2, especially when the machine is connected to the N2O pipeline supply; d) the presence of a reserve cylinder of oxygen connected to every anaesthetic machine.

Air↗
PubMed1994

[Distribution of a hypoxic gas mixture by retro-pollution of a medical gas distribution system].

The authors report a case of retropollution through the defective gas mixer of a Logic O4T-IMV ventilator (Ohmeda) located in the recovery room. Due to a defective check valve inside the mixer, medical air entered into the oxygen pipeline when the O2 pressure decreased below the pressure inside the medical air pipeline. This incident resulted in episodes of hypoxic gas mixture delivery in the operating theatre, when nitrous oxide was associated with oxygen polluted with medical air. The occurrence of such an incident, rarely described so far, requires the association of several factors. It can be recognized without delay with the continuous use of an oxygen analyser.

Air↗
PubMed1993

[Peroperative perfusion of fentanyl or sufentanil: plasma concentrations and postoperative respiratory changes].

This study was designed to assess postoperatively the time course of respiratory depression due to fentanyl (F) or sufentanil (S), as well as the plasma concentrations. Seventy patients scheduled for orthopaedic surgery lasting more than 3 hours were randomly assigned to two groups, F (n = 8) or S (n = 9). Anaesthesia was induced with etomidate (0.3 mg.kg-1), droperidol (0.15 mg.kg-1), vercuronium (0.1 mg.kg-1), a loading dose of either F (10 micrograms.kg-1) or S (1 microgram.kg-1), and maintained with 60% nitrous oxide in oxygen, and an infusion of F (6 micrograms.kg-1.h-1) or S (0.6 microgram.kg-1.h-1). Mechanical ventilation was maintained postoperatively in the recovery room until the patient could be extubated. PetCO2, SpO2, fR and F and S plasma concentrations were assessed at the end of the opioid infusion, at extubation, every hour for the first 6 hours, and thereafter every 2 h for a further 10 and 18 h. Time to extubation was the same in both groups (301 +/- 141 and 307 +/- 148 min). At the time, plasma concentrations of F and S were 1.35 +/- 0.9 ng.ml-1 and 0.14 +/- 0.07 ng.ml-1 respectively. Secondary peaks in plasma concentration (78% mean increase in comparison to the previous figure) were observed in 6 patients in group F. No similar peaks occurred in group S. Mean elimination half-life was shorter with sufentanil (457 +/- 130 min) than with fentanyl (325 +/- 132 min) (not significant). The results of this study suggest that sufentanil results less frequently in postoperative secondary peaks than fentanyl.

Adult↗
PubMed1993

Effects of thoracic extradural block on diaphragmatic electrical activity and contractility after upper abdominal surgery.

BACKGROUND: Upper abdominal surgery (UAS) induces diaphragmatic dysfunction. Thoracic extradural block (TEB) using 0.5% bupivacaine improves some pressure and motion indices of diaphragmatic function. However, no direct information on diaphragmatic activity is available after UAS. The aim of this study was to assess diaphragmatic electrical activity (Edi) after UAS before and after TEB. METHODS: A postoperative electromyogram was obtained, using intramuscular electrodes inserted by the surgeon in the costal and crural parts of the diaphragm, in 14 patients undergoing abdominal aortic surgery. Tidal changes in abdominal (VAB) and rib-cage (VRC) volumes, and gastric (delta Pgas), esophageal (delta Pes), and transdiaphragmatic (delta Pdi) pressures were used to measure tidal volume (VT) and respiratory rate and to provide indirect indices of diaphragmatic activity from the two ratios VAB/VT and delta Pgas/delta Pdi. These respiratory variables were obtained preoperatively. Postoperatively, measurements including Edi were obtained before and after a segmental epidural block, reaching a T4 level was achieved with 0.5% plain bupivacaine. RESULTS: Upper abdominal surgery induced an increase in respiratory rate (+28 +/- 15%; P < .01), associated with a decrease in VAB/VT (from 0.75 +/- 0.11 to 0.07 +/- 0.08; P < .01), delta Pgas/delta Pdi (from 0.3 +/- 0.08 to 0.01 +/- 0.19; P < .05), and VT (-30 +/- 14%; P < .01). After surgery, all patients exhibited electrical diaphragmatic activity that increased with TEB by 48 +/- 28% (P < .01) and 60 +/- 22% (P < .001) for the cural and costal segments, respectively. The ratio delta Pdi/Edi, used to evaluate diaphragmatic contractility, was not modified by TEB. Tidal volume, respiratory rate, and delta Pgas/delta Pdi returned to preoperative levels, whereas VAB/VT increased but remained different from preoperative values. CONCLUSIONS: This study demonstrates that TEB produces an increase in diaphragmatic activity, identical for the two segments of the muscle. Interruption of afferents that produce an inhibitory effect on diaphragmatic activity appears the most attractive hypothesis to explain the consequences of TEB after UAS.

Aorta, Abdominal↗
PubMed1993

Respiratory physiology in upper abdominal surgery.

This article describes the pathophysiology of the respiratory system after upper abdominal surgery, emphasizing the role of respiratory muscle dysfunction. The history of current techniques to measure respiratory muscle function are reviewed. The authors describe the postoperative pattern of breathing, speculate on the physiologic mechanisms responsible and discuss the data supporting the role of reflexes arising from the abdomen and the shift of neural output to different respiratory muscles. Finally, the authors review the impact of "closed" surgical interventions such as laparoscopic cholecystectomy.

Abdomen↗
PubMed1992

[A study of 11 ventilators for anesthesia: laboratory testing].

Eleven anaesthesia ventilators were instrumentally tested under various conditions. They included: Excel and Modulus II Plus (Ohmeda); 710 and Servo anaesthesia circle 985 (Siemens); Jollytronic (Soxil) and Elsa (Engström); SA2 and Cicero (Dräger); ABT 4,300 (Kontron); Monnal A and the prototype Alys (Taema). The test circuit comprised a two compartment model lung, a pneumotachograph, a pressure gauge in the "airway". The volume was calculated as the integral of flow rate. Each machine was calibrated by the firms' technicians. Before each test, the pneumotachograph was calibrated using a 11 air syringe and the pressure gauge with a 5 cm water column. Each machine ventilated the model lung for 30 min before starting the tests. There were five tests: 1) reliability of the machine's spirometer, 2) reliability of the ventilation rate, 3) reliability of pressure measurements, 4) effect of increasing fresh gas flow on spirometry, 5) effect of increasing downstream resistances. In usual simulated ventilatory conditions, all the machines accurately delivered the setted ventilation and spirometric measurements were with minimal error only. Several ventilators (SA2, Excel, 710, Elsa, ABT 4,300) did not succeed in maintaining their performances when compliance was strongly decreased or resistance of the test lung notably increased. Resistance in the circuit during simulated spontaneous ventilation was < 3.6 cmH2O.l-1.s-1. Increasing fresh gas flow raised the minute volume delivered in six ventilators. It is concluded that, during extreme ventilatory conditions, the inspired volume must be adjusted so as to maintain the inspired tidal volume. However, ventilators which increase inspiratory time in response to an increased mechanical load cannot be adjusted by this way.

Anesthesia, Closed-Circuit↗