Benzodiazepine anesthesia in humans modulates the interleukin-1 beta, tumor necrosis factor-alpha and interleukin-6 responses of blood monocytes.

The influence of sedative and anxiolytic benzodiazepines on human monocyte function was assessed in 11 patients undergoing anesthesia prior to control endoscopy of the urinary tract. A single i.v. injection of 0.08 mg/kg midazolam induced a marked and delayed inhibition of the lipopolysaccharide-induced production of interleukin-1 beta, tumor necrosis factor-alpha and interleukin-6 by monocytes isolated from peripheral blood. Corticosteroids were not responsible for the observed immunosuppression. These studies demonstrate that, when administered in man, benzodiazepines markedly alter the capacity of monocytes to synthetize major mediators of the host inflammatory response.

Measurement of post-operative pain and narcotic administration in infants using a new clinical scoring system.

We developed a clinical neurologic and behavioral scoring system composed of 10 items to measure the post-operative pain levels in infants: (1) sleep during preceeding hour, (2) facial expression of pain, (3) quality of cry, (4) spontaneous motor activity, (5) Spontaneous excitability, (6) flexion of fingers and toes, (7) sucking, (8) global evaluation of tone, (9) consolability and (10) sociability. Using this system, a group of infants ranging from one to seven months in age and undergoing minor surgical procedures was studied. The infants were randomly assigned to two groups: Group I received Fentanyl intravenously (3 micrograms/kg) prior to surgery, and Group II received a placebo. The infants then were studied post-operatively in the recovery room at 30, 60, 90 and 120 min intervals. Over the entire post-operative observation period, 54% of the infants in Group I had satisfactory analgesia compared to 18% in Group II. There were no significant differences in Group I and Group II in oxygenation, carbon dioxide elimination, blood pressure, heart rate or temperature.

[Prehospital fibrinolysis with rt-PA in acute myocardial infarction]. / Fibrinolyse préhospitalière par rt-PA dans l'infarctus aigu du myocarde.

Thrombolytic therapy has been shown to be very effective in the acute phase of myocardial infarction and the benefits are greater if the treatment is initiated as soon as possible. In France, early treatment in the prehospital phase is possible through the SAMU, an emergency ambulance and care unit organisation. Between December 1987 and November 1988, 80 patients (73 men and 7 women) with an average age of 55 +/- 9 years were treated by rt-PA (100 mg i.v. in 90 minutes) for acute myocardial infarction within three and a half hours of the onset of symptoms. The average delay between the onset of pain and the administration of rt-PA was 126 +/- 43 minutes, which represents an estimated average time gain of 55 minutes compared with thrombolysis started after hospital admission. No haemorrhagic or allergic complications occurred during hospital transfer and there was no mortality. There were, however, two diagnostic errors. Thrombolysis was estimated to be effective on clinical, electrocardiographic and enzymatic criteria in 60 p. 100 of cases. Thirty early coronary angiographies (within 48 hours) showed that 83 p. 100 of the arteries thought to be responsible for the infarct were patent. Haemorrhage was a rare complication during the hospital phase and had a favourable outcome. Hospital mortality was 6 per cent. The low morbidity and the reliability of diagnosis indicate that prehospital thrombolysis is feasible in the acute phase of myocardial infarction.

[Anesthesia and bone marrow harvesting in children]. / Anesthésie et don de moelle osseuse chez l'enfant.

Allogeneic bone marrow transplantation is increasingly used to treat a great variety of disorders which range from genetic conditions to leukaemia. Most often, the donor is a healthy sibling of the patient. Bone marrow harvesting in young children is a very painful procedure requiring anaesthesia; this presents yet more risk for the donor. In order to analyse the specific problems related to this procedure, a retrospective study was carried out on 30 anaesthetic records of marrow-harvesting procedures performed between January 1980 and December 1987. The 30 harvests were carried out in 28 patients (15 boys, 13 girls). Mean age of donors was 6 +/- 0.8 yr (range: 13 months to 17 yr). Twenty-seven patients were classed ASA I and one ASA II. The harvests were all carried out in prone and intubated patients. The volume of removed marrow was 350 +/- 80 ml (range 170 to 600 ml). This was equivalent to a mean 21% estimated blood volume (6-37%). Blood transfusion with phenotyped irradiated blood was carried out in 18 patients, and with autologous blood in one. Mean duration of the procedure was 88 +/- 6 min and the mean stay in hospital was three days. The potential risks for the children are discussed, as well as the related legal problems.

[Electric infusion devices: criteria of choice and comparative analysis of 45 models available in France]. / Appareils électriques de perfusion: critères de choix et analyse comparative de 45 modèles disponibles en France.

This study compared 45 electric infusion devices, either constant flow pumps or syringe pumps, available in France. These devices were tested for start-up delay, time to alarm following occlusion, bolus following occlusion, accuracy of flow rate and pressure output. Ergonomic, environmental and various technical criteria such as safety in continuous perfusion, correct positioning of infusion sets, air in line and end of perfusion detection were also considered. Users can compare these devices in easy to read tables. The newest devices include systems improving the quality of flow.

[Electric infusion devices]. / Les appareils électriques de perfusion.

Electrical infusion devices are specifically aimed to maintain an accurate and constant flow rate. The infused agents can be allocated into three categories of risk, according to their therapeutical index and their infusion rate. Each category requires infusion devices with the corresponding performances. Moreover the choice of a device depends also on ergonomical and environmental criteria as the area of use (e.g. ambulatory patient, transport, neonates, intravenous anaesthesia).

[Ventilation with metallic tubes in CO2 laser surgery of the larynx]. / Ventilation par sonde métallique pour la chirurgie laryngée au laser CO2.

One of the risks of laryngeal laser surgery is the ignition of the disposable plastic endotracheal tubes used for ventilation. In 1985, Hunton and Oswal (Anaesthesia, 40: 1210, 1985) developed a metallic tube which is now available in France. In this study, the tube has been tested on 30 patients undergoing this type of surgery. The tube was sterilized in glutaraldehyde before re-using it. There never was any problem with placing the tube and surgical conditions were satisfactory. There was neither incident due to the laser, nor any difficulties with the use of high-frequency jet-ventilation. The blood gas values were satisfactory (mean PaO2: 19.4 +/- 4.2 kPa; mean PaCO2 5.0 +/- 0.46 kPa). After a use in 30 consecutive patients, the tube was not damaged. The advantages and disadvantages of this tube are discussed, considering the other types of special laser surgery endotracheal tubes. This metallic tube is not flammable, can be used several times, occupies only a small space and does not hurt tissues. Moreover, it is cheaper than disposable tubes when the price is calculated per patient. It would therefore seem that Hunton and Oswal's metallic tube, used with high-frequency jet-ventilation is a good alternative for tubes used today.

[Fatal pulmonary leukoagglutination after administration of fresh frozen plasma]. / Leucoagglutination pulmonaire mortelle après administration de plasma frais congelé.

A case is reported of a 73 year old female patient who died during surgery for enlarged nephrectomy as a result of a massive non-cardiogenic pulmonary oedema. She had been given 2 red cell concentrates (450 g) and 3 fresh frozen plasma units (900 g). A postmortem examination did not reveal any pulmonary embolus, acute myocardial infarct, haemorrhage or cardiac tamponade. Further tests on the sera of the 5 plasma donors revealed a neutrophil-specific anti-NA2 antibody. Alveolar leukostasis was confirmed on the postmortem lung slices. This type of transfusion accident occurs for about 1 in 5,000 units transfused, fortunately not all as serious. This case confirms once more that fresh frozen plasma is not the ideal treatment for acute hypovolaemia, 4% human albumin being safer.

[Continuous monitoring of mixed venous oxygen saturation in anesthesia in pulmonary surgery]. / Surveillance continue de la SvO2 au cours de l'anesthésie pour chirurgie pulmonaire.

The multiplicity of potential causes of variations in mixed venous oxygen saturation (SvO2) during one lung ventilation (OLV), including a constant ventilation/perfusion mismatch, explains that it has been suggested as a routine monitoring procedure. To assess its usefulness, 12 adults undergoing OLV were monitored during surgery with an Oximetrix pulmonary catheter, placed on the side opposite to the surgical field under fluoroscopic control. Seventy two complete sets of haemodynamic measurements were obtained at 6 different times during surgery. We studied the ability of changes in SvO2 to predict changes in arterial oxygen saturation (SaO2), cardiac output (CO), and venous admixture (VA) by calculating sensitivities (Se), specificities (Sp) and predictive values with regard to these variables. There were no complications due to the protocol. However left-sided catheter placement failed in four cases. Correlation between optical and measured SvO2 was very strong (r = 0.94; p less than 0.001). SvO2, oxygen consumption (VO2) and the rate of oxygen extraction remained constant throughout the procedure, even when CO, mean arterial pressure, VA, SaO2 and PaO2 varied. Clamping the pulmonary artery returned VA, SaO2 and PaO2 values to those found before OLV, but produced a significant decrease in CO. SvO2 had low Se and Sp for changes in other variables (CO: 76 +/- 7, 48 +/- 9; PaO2: 79 +/- 6, 59 +/- 9; VA: 54 +/- 7, 48 +/- 7 respectively). In this type of surgery, alterations in variables related to oxygen are probably balanced by haemodynamic changes. In fact, according to Fick's formula, SvO2 is almost completely determined by SaO2 and CO, when VO2 and haemoglobin remain stable.(ABSTRACT TRUNCATED AT 250 WORDS)

[Comparison of the antithrombotic effects of heparin, enoxaparin and prostacycline in continuous hemofiltration]. / Comparaison des effets antithrombotiques de l'héparine, l'énoxaparine et la prostacycline au cours de l'hémofiltration continue.

Continuous anticoagulation is required during haemofiltration to prevent the deposition of fibrin and the formation of thrombus which would lead to early clotting of the haemofilter. This study aimed to compare the efficiencies of 3 different anticoagulation protocol: 150 IU.kg-1.day-1 heparin (group HEP), 1.2 mg.kg-1.day-1 enoxaparin (group ENX), and a combination of 0.8 mg.kg-1.day-1 enoxaparin with 5 ng.kg-1.min-1 prostaglandin I2 (group ENX and PGI2). A flat ANS69S (Hospal) haemofilter was used for continuous venovenous haemofiltration. Antithrombotic efficiency was assessed with a haemofilter permeability index (HPI) including the transmembraneous pressure gradient and the rate of production of ultrafiltrate. The time required for HPI to decrease to 1/3 of its initial value (HPI1/3) was used to compare the 3 protocols. Treatment tolerance was judged by monitoring the usual haemodynamic and haemostatic parameters. No adverse effects (bleeding, thrombosis, hypotension) were observed. HPI1/3 was 15.1 +/- 2.4 h, 18.3 +/- 3.1 h and 28.2 +/- 4.2 h in groups HEP, ENX and ENX and PGI2 respectively. High dose enoxaparin reached antithrombotic efficiency without increasing the risk of haemorrhage. The use of low doses of prostaglandin I2 greatly increased HPI1/3, without any deleterious haemodynamic effects. However, the high cost of prostaglandin I2 needs to be put in the balance with the increase in duration of haemofilter life. Therefore, further investigations are required to evaluate the possible synergy between heparin and prostaglandin I2, as well as the biological parameters which need to be monitored.

[Antishock trousers in the prevention of air embolism]. / Le pantalon antichoc dans la prévention de l'embolie gazeuse.

This study aimed to assess the efficiency and safety of military anti-shock trousers (MAST) in preventing venous air embolism in children undergoing neurosurgical procedures in the sitting position. It included 26 children, 7.7 +/- 4-year-old and weighing 25.4 +/- 10.5 kg. All had the same anaesthetic protocol including premedication with oral lorazepam, induction with thiopentone or propofol with fentanyl and vecuronium, and maintenance with isoflurane and a continuous infusion of fentanyl. In 10 patients, a retrograde central venous catheter was inserted for measurement of pressure in the superior bulb of the internal jugular vein. Haemodynamic measurements were carried out with the patient supine; with the patient sitting, the MAST not being inflated; 10 min after inflation of the MAST (40 mmHg in the limbs, 30 mmHg in the abdominal part); after starting 10 cmH2 O positive end expiratory pressure; and after fluid administration with 5 ml.kg-1 macromolecules (Plasmion). The criterion for air embolism was a decrease in PetCO2 of more than 5 mmHg over more than 30 s, not preceded by respiratory or cardiovascular impairment. Inflation of the MAST resulted in a dramatic rise in venous pressure, still reinforced by minor PEEP. Transmission of pressure from the right atrium to the dural sinus was linear, and seemed to be sufficient to prevent occurrence of detectable venous air emboli. No deleterious side-effects were noted. This method would therefore seem to be very efficient, preserving the advantages of the sitting position, and restricting its disadvantages. Unfortunately, the limited availability of different paediatric sizes of MAST reduces the possible uses of this method.

[Perinatal medicine in the year 2000 seen by the anesthesiology-resuscitation specialist]. / La médecine périnatale en l'an 2000 vue par un anesthésiste-réanimateur.

Every year, 40.000 preterm babies are born in France, 10.000 of them being born before 33 weeks of gestation. They represent 1.2% of birth rate, but 50% of neonatal mortality. If IVF (in vitro fertilization) is the cause of less than 1% of all births, it is the cause of 7% of very preterm babies. Resuscitation of the very premature born infants has improved their survival rate but led to some adverse outcome. So, it is necessary to design a long term follow-up for children born from IVF, to evaluate the neonatal resuscitation and to improve treatment and care of children with developmental abnormalities.

[Practical aspects of the laryngeal mask]. / Aspects pratiques du masque laryngé.

The laryngeal mask (LM) is increasingly used. An overview is made: description, insertion, cardiovascular responses, advantages, LM and aspiration, LM as an aid to ventilation, indications, LM in difficult intubations, contra-indications, sterilization and cost.

[Comparative use of thiopental and methohexital in patients anesthesized for E.N.T. endoscopy. Apropos of 60 cases]. / Utilisation comparée du thiopental et du méthohexital chez les patients anesthésiés pour endoscopie O.R.L. A propos de 60 cas.

The clinical effects of methohexital versus thiopental are studied in 60 randomized patients anaesthetized for E.N.T. endoscopy or laser surgery of the larynx. Thiopental is injected by I.V. bolus (5 mg/kg) and methohexital is administered by continuous infusion (0.1 mg/kg/min). Fentanyl is the analgesic and succinyl-choline is used for curarisation. All patients are ventilated by a conventional ventilator or by high frequency ventilation. Side-effects, extubation time, and recovery estimated by the Newman-test modified by Weber are studied. The only difference between methohexital and thiopental is a better recovery-score at 30 minutes for the methohexital group.