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P Feiss

Publications and source records attributed to P Feiss.

At least 55 records · Page 3Linked to original sources
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

[Intra-arterial thrombolysis of acute mesenteric ischemia].

A 73-year-old man with pre-existing cardiac failure, coronary artery and chronic obstructive pulmonary disease was presented for an acute mesenteric ischaemia, resulting from an embolic obstruction of the superior mesenteric artery. An intra-arterial fibrinolysis with a bolus of 250 000 units of streptokinase, followed by an infusion of 150 mg rtPA with adequate heparin dosage was performed 10 hours after the first symptoms. An abdominal guarding occurred 24 hours later, despite radiological improvement, justifying emergency surgery which confirmed the partial efficiency of the medical therapy. Unfortunately, a cardiogenic shock occurred preoperatively and the patient died five days later from intractable cardiovascular failure.

Acute Disease↗
PubMed1995

[Measurement of tympanic temperature by infrared and thermocouple thermometry. A comparative study].

OBJECTIVE: To compare tympanic temperatures obtained with an infrared thermometer Core Check 2090A (IVAC), non in contact with the tympanic membrane, to values obtained with a thermocouple thermometer Mon-A-Therm (Mallinckrodt) in contact with it, and to assess whether the differences depend on the person measuring the temperature. STUDY DESIGN: Prospective comparative open study. PATIENTS: The study included 150 adults in whom the tympanic temperatures were measured at their admission to recovery room by 10 nurse anaesthetists. METHODS: Each thermometer was inserted in the same patient into an external acoustic meatus. The median and range of the temperature differences were used to assess the bias and the accuracy of the measures. Their reliability was analyzed with consideration of the measuring person and the presence of irrelevant values, defined as a temperature difference over 0.3 degrees C. RESULTS: The temperatures obtained with both devices were similar (36.2 +/- 0.7 degrees C with IVAC thermometer vs 36.2 +/- 0.8 degrees C with Mallinckrodt thermometer). The median value of the differences was 0 degrees C, with a range of 2.5 degrees C (maximum value + 1.5 degrees C, minimum value: -1 degree C). Nineteen patients could be qualified as hypothermic (temperature < 36.5 degrees C) with one thermometer and normothermic (temperature > or = 36.5 degrees C) with the other. Among them, only 9 (6%) had temperature differences above 0.3 degrees C. The temperature differences were not different according to the measuring nurse. Nevertheless two of them obtained major differences or irrelevant figures. CONCLUSIONS: As compared to the thermocouple thermometry, infrared thermometry has no bias but a low precision. The measurement error does not allow the recognition of hypothermia in 6% of patients. The error may be made by the measuring person and/or related to the anatomy and the patency of the external acoustic meatus. Tympanic infrared thermometry seems to be a convenient method for temperature measurements at short time intervals in the recovery room, provided its limitations are kept in mind.

Adult↗
PubMed1995

Effects of a paf-receptor antagonist on hemodynamics during and after cardiopulmonary bypass.

OBJECTIVES: To assess after cardiopulmonary bypass (CPB) the role of paf-acether (paf), a phospholipid mediator whose injection in animal mimics the hemodynamics observed after CPB. DESIGN: Prospective double-blind randomized study. SETTING: Single institutional university hospital. PARTICIPANTS: 18 patients scheduled to undergo coronary artery bypass graft. INTERVENTIONS: 18 patients randomly received a placebo (n = 8) or 120 mg BN52021 (n = 10), a paf-receptor antagonist injected twice just before vascular cannulation and before cross-clamp release. MEASUREMENTS AND MAIN RESULTS: Hemodynamic measurements were performed with a pulmonary artery and a radial artery catheter before and after the first injection of BN52021 or placebo, at the end of CPB, 1, 15, and 30 minutes after protamine infusion, then 6 hours and 24 hours postoperatively. BN52021 infusion, did not affect hemodynamic parameters. After CPB, the pulmonary artery pressures, the cardiac index, and the pulmonary artery occlusion pressures were statistically the same between groups. By contrast, the pulmonary vascular resistances (1.5 +/- 0.5 IU v 4.5 +/- 0.6 IU, p < 0.05), the right ventricular systolic work index (5.3 +/- 0.91 g m m-2 v 9.37 +/- 1.02 g m m-2, p < 0.05) and the transpulmonary gradient (4.7 +/- 1.1 mmHg v 12.0 +/- 1.2 mmHg, p < 0.05) were lower in the BN52021 group as compared with the placebo group. After protamine infusion, these differences between groups disappeared. CONCLUSION: Because the inotropic and vasodilator therapy and the volume loading were the same between groups, this study suggests that pretreatment with a paf-receptor antagonist improves post-CPB pulmonary resistance. Nevertheless, this beneficial effect is transient without consequences on left ventricular function indices.

Blood Pressure↗
PubMed1995

[Pharmacokinetics of lidocaine and bupivacaine after peribulbar block with additional hyaluronidase].

OBJECTIVE: To assess the time course of plasma concentrations of lidocaine and bupivacaine associated with hyaluronidase for peribulbar block. STUDY DESIGN: Prospective study. PATIENTS: Ten patients (mean age = 71 +/- 11 yrs, mean weight 63 +/- 10 kg) scheduled for cataract surgery with lens implantation. METHOD: Lidocaine 2% (5.5 mL = 110 mg) and bupivacaine 0.5% (5.5 mL = 27.5 mg) associated with hyaluronidase (80 IU) were injected supra and infra-orbitally, in patients premedicated with midazolam. Blood samples wer0 collected at constant time intervals from the end of infiltration until the 6th hour. The plasma concentrations of local anesthetics were measured with the HPLC technique. RESULTS: The median plasma peak concentration was 1.74 mg.L-1 after 10 min for lidocaine, and 0.52 mg.L-1 after 7.5 min for bupivacaine respectively. CONCLUSIONS: The similar delays of occurrence of peak concentrations confirm that liposolubility is not the only factor of diffusion of local anaesthetics from the periocular fat into the blood stream. The peak concentrations are far below the alleged toxic concentrations. When associated with hyaluronidase, the peak concentrations occur as rapidly as after endotracheal or paracervical administration.

Aged↗
PubMed1995

[Prescribing and performing autologous blood transfusion: experience at a University Medical Center].

Prescription and carrying out of autologous blood transfusion in a university hospital during a whole year (1992) were investigated. 554 patients were involved. 88% of them gave at least one blood unit. Three surgical groups are specified: cardiac surgery with bypass (95 patients), orthopaedic procedures with knee or hip replacement or spine surgery (276 patients) and other types of surgery (117 patients). Prescriptions of blood donation before cardiac surgery were not carried out (by the transfusion centre) twice more often than in the other groups. This is why autologous blood taking is now effected in the anaesthetic unit. 88.9% (n = 434) of all patients did not receive homologous blood (90% in the orthopaedic group, 84% in the cardiac group). 25% of the collected units were not transfused. This figure is only 8% for the cardiac patients. An efficiency index is suggested taking in account the transfusion of autologous blood units and the need of homologous transfusion: % autologous used units x % procedures realized without homologous blood. The good rate to achieve could be 70%. In aorto-coronary bypass surgery when no autologous blood was collected preoperatively, 57.5% patients received homologous blood vs 16% when at least one unit was predeposited. A short review of literature shows an increasing place of predeposited autotransfusion, with some limits in orthopaedic surgery where a combination of autologous blood donation and other erythrocytes saving methods appears to give the best results. Erythropoietin, critical haemoglobine concentration threshold, autologous transfusion in cancer patients still need further studies.

Academic Medical Centers↗
PubMed1994

Effects of the platelet-activating factor receptor antagonist BN 52021 on hematologic variables and blood loss during and after cardiopulmonary bypass.

Cardiopulmonary bypass (CPB)-induced thrombocytopenia and leukopenia is augmented after heparin reversal of protamine. Platelet-activating factor (PAF) might be implicated in these disorders. To evaluate the effects of PAF on the hematologic disorders and blood loss during and after CPB, patients were pretreated with BN 52021, a PAF receptor antagonist, or a placebo. BN 52021 (120 mg) (n = 13) or placebo (n = 15) were infused intravenously before vascular cannulation and before cross-clamp release. Platelet and leukocyte counts were assessed in venous blood before and after the first dose of BN 52021 or placebo, 2 min after the beginning of CPB (at the entry of the oxygenator), at the end of CPB, 1, 15, and 30 min after protamine infusion, and 6 and 24 h after CPB. The decrease in platelet and leukocyte counts were the same between groups during and after CPB and after protamine infusion. Bleeding times were not modified by the pretreatment of patients with BN 52021. During surgery, blood loss reached 1660 +/- 297 mL in the BN 52021 group and 1599 +/- 283 mL in the placebo group (P > 0.05). Forty-eight hours postoperatively, the chest tube outputs were not different between groups (1460 +/- 418 mL vs 1640 +/- 362 mL in the BN 52021 and placebo groups, respectively). This study shows that BN 52021 infusion did not change the hematologic variables studied. Moreover, a PAF antagonist pretreatment did not protect the patients against CPB- or protamine-induced hematologic changes.

Analysis of Variance↗
PubMed1993

[Pharmacokinetics of epidural or intrathecal bupivacaine in elective cesarean section].

Twenty ASA 1 pregnant women at term, undergoing elective Caesarean section were included in this study. They were randomly assigned to one of two groups, receiving either a spinal or an epidural anaesthesia. Before induction, in order to prevent hypotension, all patients were given an i.v. infusion of 1000 ml of Ringer-lactate and a subcutaneous injection of ephedrine 30 mg. They were positioned on the operating table with a 15 degrees left lateral tilt. Spinal anaesthesia was performed with hyperbaric bupivacaine 0.5 p. cent (0.08 mg.cm-1 of height). Epidural anaesthesia was obtained with a bolus dose of 0.5 p. cent plain bupivacaine, followed by a continuous infusion through the epidural catheter until the level of surgical block reached T6 bilaterally. Bupivacaine was assayed in plasma by high performance liquid chromatography (HPLC). Following pharmacokinetic parameters of bupivacaine were determined: Cmax (maximal concentration), Tmax (time to reach maximum), AUC (area under curve), Cl (total plasma clearance), Vz (volume of distribution during the elimination phase), T1/2 (elimination half-life). Bupivacaine concentration was also measured in samples obtained at birth from umbilical vein and umbilical artery. The mean dose of bupivacaine used was 12.8 +/- 0.6 mg in the spinal group and 118.6 +/- 17.8 mg in the epidural group. The time of onset of surgical anaesthesia was significantly shorter with spinal anaesthesia (7.6 +/- 4.4 vs 31 +/- 11.1 min; p < 0.01). The sensory block had a longer duration in epidural group (223.2 +/- 15 vs 291 +/- 13.8; p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Epidural↗
PubMed1993

[Infusion of propofol or closed-circuit isoflurane. A study of cost].

The choice of an anaesthetic agent is influenced by its cost. The use of a circle absorber system decreases the cost of the maintenance of anaesthesia with halogenated agents. Fast recovery and low incidence of postoperative nausea and vomiting are the main advantages of propofol. The cost of propofol can limit its use for the maintenance of anaesthesia except for short procedures. This prospective study compared in 50 ASA 1 and 2 patients the cost of anaesthesia with either propofol (group P, n = 25) or the association thiopentone-isoflurane administered with a rebreathing circuit (group I, n = 25). Patients were premedicated the evening before surgery with 2.5 mg lorazepam. Anaesthesia was induced with either propofol (2-3 mg.kg-1) or thiopentone (4-6 mg.kg-1) and maintained with either propofol (6-10 mg.kg-1.h-1) in group P or isoflurane continuously injected as liquid in the expiratory limb of the circuit in group I. The side effects of anaesthesia and the delay of recovery and discharge from the recovery room were assessed. Peroperative cost of anaesthesia included nitrous oxide, isoflurane and i.v. agents, fluids volumes and disposable devices. The total cost of anaesthesia included also the recovery room stay. The mean duration of anaesthesia was not significantly different between the two groups (109.4 +/- 7.1 min vs 107.3 +/- 7.3 min group P vs group I). The delay lf recovery (eyes opening) was shorter in the propofol group (14.4 +/- 1.3 min vs 19.4 +/- 1.4 min) as well as the delay of discharge from the recovery room (70 +/- 4 min, vs 82.4 +/- 4.6 min).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

[Acute respiratory distress caused by a mediastinal pancreatic pseudocyst].

The pseudocyst of the pancreas is a frequent complication of acute pancreatitis. However to intrathoracic localization remains exceptional. A case of acute respiratory insufficiency in a 66-year-old man in whom artificial ventilation was required for such a complication is reported. This case stresses the difficulty often encountered for the differential diagnosis of these liquid tumors. The clinical signs are variable and non specific, especially in case of absence of any history of pancreatitis. The radiographic studies, in particular ultrasonography and CT-scanner defines its liquid nature and its connections. Endoscopy examination confirms its retro-oesophageal extension due to the migration through the oesophageal hiatus. Only the percutaneous needle aspiration of a collection or an associated pleural effusion confirms the diagnosis by the high content of amylases. The treatment of this type of localisation is surgical and essentially consists of an internal derivation.

Acute Disease↗
PubMed1993

Pharmacokinetics of propofol and its conjugates after continuous infusion in normal and in renal failure patients: a preliminary study.

The pharmacokinetics of propofol, 2,6 diisopropylphenol, were compared in 6 end-stage renal failure patients aged 66.3 +/- 12.1 years and in 5 normal patients aged 45.5 +/- 13.5 years. Anesthesia was induced with propofol (2 and 2.5 mg.kg-1 respectively) and fentanyl (0.1 mg). Anesthesia was maintained with propofol (9 and 10 mg.kg-1 x h-1 respectively). Patients breathed spontaneously a 50 per cent oxygen in nitrous oxide mixture. Two ml blood samples were taken during anesthesia and at regular intervals until up to 24 hours after infusion. Plasma levels of propofol were determined by HPLC with electrochemical detection. Propofol conjugates were determined after hydrolysis with beta glucuronidase or HCl. Results were expressed as median [lower-upper percentiles]. Propofol clearance (1.53 [1.02-2.10] L.min-1 x kg-1 versus 1.65 [1.39-1.78] L.min-1 x kg-1 in normal patients), and half-lives elimination were not modified by renal failure. Renal failure patients exhibited a higher volume of distribution at steady state as compared to normal patients (19.28 [11.71-76.81] L.kg-1 versus 8.60 [6.58-9.81] L.kg-1, p < 0.05). Renal failure did not affect the production of conjugates but they accumulated in blood of renal failure patients. Despite this, no difference in time to eyes opening and propofol concentration were observed, confirming the absence of clinical effect of these metabolites.

Adult↗
PubMed1993

Comparison of omeprazole with cimetidine for prophylaxis of acid aspiration in elective surgery.

Gastric pH and volume were measured in four groups of 15 patients scheduled for elective surgery. The patients were randomly allocated to receive either no antacid, oral omeprazole 40 mg the evening before surgery, oral omeprazole 40 mg 2 h before surgery, or effervescent cimetidine 800 mg, 2 h before surgery. Anaesthesia was induced with thiopentone (4-6 mg kg-1), fentanyl (0.03 mg kg-1) and vecuronium (0.1 mg kg-1) and maintained with nitrous oxide in oxygen (50/50) and isoflurane. After induction of anaesthesia and on completion of surgery, gastric pH (mean +/- SEM) and volume were measured using a glass electrode and a phenol red dilution technique. Gastric pH were significantly higher in the three treated groups than in control (P < 0.01). Omeprazole and cimetidine were equally effective in reducing volume and pH of the gastric juice at the beginning and at the end of anaesthesia. Nevertheless 14.2 and 28.5% of patients who received omeprazole respectively the day before or the morning of surgery remained at risk of aspiration pneumonitis (gastric pH < 2.5 and gastric volume > 25 ml).

Administration, Oral↗
PubMed1992

Variations of blood PAF-acether levels during coronary artery surgery.

Extracorporeal circulation (ECC) is associated with thrombocytopenia and transient leukopenia. After ECC and coronary artery bypass graft (CABG) surgery, some patients can develop pulmonary and cardiac dysfunction, which might be related to the release of various mediators such as thromboxane A2, C5a, and C3a anaphylatoxins. The involvement of PAF-acether (PAF), a potent vasoactive thrombocytopenic and leukoneutropenic agent, has not been determined. Therefore, 10 patients were studied during and after CABG. The release of PAF, lipo PAF (PAF bound to blood lipoproteins), and lyso PAF (PAF precursor and metabolite) was measured in blood from the left atrium, radial artery, and pulmonary artery before and after CABG. PAF, lipo PAF, and lyso PAF were also determined during ECC at the entry and exit points of the oxygenator. Hemodynamic parameters, platelet, and leukocyte counts in the pulmonary artery were measured simultaneously. PAF did not increase significantly during ECC; it showed a transitory six-fold increase immediately after CABG in the radial artery (0.18 +/- 0.13 v 1.09 +/- 0.36 ng/mL, P < 0.05), but not in the pulmonary artery (0.10 +/- 0.03 v 0.56 +/- 0.21 ng/mL, P > 0.05). Blood PAF amounts in the radial artery were significantly higher than in the left atrium following ECC (1.09 +/- 0.36 v 0.06 +/- 0.04, P < 0.05), probably indicating PAF production in the heart. No variation of blood lipo PAF and lyso PAF was observed. No correlation was seen between PAF amounts and blood cell count.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Pressure↗
PubMed1992

[Prevention of postoperative nausea and vomiting by ondansetron].

This study was carried out to assess the efficacy of oral ondansetron, a new 5HT3 receptor antagonist, in patients undergoing thyroid surgery. It included 60 patients, randomly assigned to two groups, and receiving orally, 1 h before induction of anaesthesia, either 8 mg of ondansetron (n = 29) or a placebo (n = 30). One patient was excluded. The same anaesthetic protocol, consisting of 3 to 5 micrograms.kg-1 of fentanyl, 4 to 6 mg.kg-1 of thiopentone, and 0.5 mg.kg-1 of atracurium, was used in all. Anaesthesia was maintained with 50% nitrous oxide in oxygen with 0.8 to 1% endtidal concentration of isoflurane and additional boluses of 0.1 mg of fentanyl as required. The incidence and intensity of nausea, graded mild, moderate or severe, and the incidence of vomiting were recorded postoperatively. During the first twelve hours after surgery, 40% of patients in the placebo group had nausea (16.7% mild, 20% moderate and 6.7% severe), and 50% vomited. In the ondansetron group, nausea and vomiting occurred in 13.8% and 20.4% of patients respectively. The 4 patients in the latter group complained of major nausea. The differences between the groups were statistically significant: p = 0.025 for nausea and p = 0.042 for vomiting. It is concluded that oral ondansetron, 8 mg taken orally 1 h before surgery, significantly reduces the incidence of nausea and vomiting during the first twelve postoperative hours. As it is easy to use and has no side-effects, it might be of interest in day-case surgery patients, despite its high cost.

Administration, Oral↗
PubMed1992

Variations in blood platelet-activating-factor levels after protamine reversal of heparin in humans.

The potent inflammatory mediator PAF-acether (PAF = platelet-activating factor) can produce the same hemodynamic and hematological effects as protamine infusion. In 10 patients, blood PAF and precursor levels were measured in the left atrium, the pulmonary and the radial artery before and after protamine reversal of heparin during coronary artery bypass graft. Blood PAF level in the left atrium increased 6-fold (17 +/- 12 pg.ml-1 vs 98 +/- 46 pg.ml-1, P = 0.03) after protamine infusion. By contrast, a 4-fold decrease was observed in the pulmonary artery blood (130 +/- 48 pg.ml-1 vs 31 +/- 23 pg.ml-1, P = 0.03) and a 9-fold decrease was noted in the radial artery blood (285 +/- 104 pg.ml-1 vs 31 +/- 15 pg.ml-1, P = 0.01). No cardiovascular impairment was observed but all patients exhibited thrombocytopenia. After protamine, PAF in the left atrium reached lower levels than those observed in the pulmonary and radial artery before protamine infusion. Moreover, no significant correlation was observed between platelet counts and PAF levels. Thus PAF seems not to mediate the platelet drop induced by heparin-protamine complexes. A positive correlation was obtained between leukocyte counts in the pulmonary artery and PAF levels in the left atrium (r = 0.78, P = 0.02). Protamine infusion may stimulate PAF biosynthesis by leukocytes in the lung, on the one hand, and accelerate the disappearance of PAF in the arterial bed, on the other hand.

Coronary Artery Bypass↗