[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.

[Emergency calls in the Samu system]. / Les appels d'urgence au Samu.

The French emergency medical system is public and medical. Named Samu, it is almost entirely managed by anesthesiologists specially trained for emergency medical assistance and advanced medical support. The system comprises a reception and dispatching center for emergency calls, directly connected to police and firemen, but assuring patient confidentiality. This fixed center is managing mobile units which are Medical Intensive Care Ambulances (MICA named Smur in France). The Samu's mission consists in performing urgent individual medical assistance and also medical services for treatment of mass casualties. It is also to find adequate hospital units for the patients, to perform medical transport and to be a consultant for general practitioners in emergency.

[Infra-orbital nerve block in early primary cheiloplasty]. / Bloc des nerfs sous-orbitaires dans les cheiloplasties primaires précoces.

A prospective study have studied the effect of infraorbital block during anesthesia in infants with a cleft lip. The study was conducted during the year 1994, in the hospital Necker Enfants-malades. During this period 51 cleft lip surgery were performed. Anesthesia for infants with cleft lip using bilateral infraorbital block is a safe, simple and quick technique, and result in a good longlasting analgesia, seems to decrease the risk of respiratory depression, and allows an immediate and comfortable awakening.

Autologous blood donation for elective surgery in children weighing 8-25 kg.

To determine whether autologous blood donation can be used safely and efficiently in children weighing 8-25 kg, we studied children whose perioperative blood losses were expected to exceed 25% of total blood volume. Blood donations were performed in pediatric units, under the direction of an anesthesiologist and a blood bank physician experienced in paediatric care. Twenty-four children, median age 6 years (1-13), were included. They underwent surgery mainly for digestive or urological disorders, and for orthopedic defects. Forty blood collections were performed of the 46 prescribed. Phlebotomies could not be performed in 1 child because of the mother's apprehension, and in 5 cases because of venous access problems. All phlebotomies were hemodynamically well tolerated. Hemodilution was also performed in 17 children, and cell saver used in 2. Allogeneic blood transfusion was avoided in 21/24 children.

Accidents following extradural analgesia in children. The results of a retrospective study.

A retrospective multicentre study of the complications observed after regional anaesthesia in children was undertaken in 1991 at the request of the association of Anesthésistes-Réanimateurs Pédiatriques d'Expression Française (ADARPEF). The incidence of accidents seen in the study was comparable to that found in the literature. Five cases which were exceptional due to the severity of the sequelae have been analysed separately. Different pathophysiological mechanisms are proposed.

[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).

Blood loss during repair of craniosynostosis.

Surgical repair of craniosynostosis carries a high risk with large blood losses. Over a 2-yr period, we have managed 115 patients undergoing craniosynostosis repair with peroperative haemodilution to achieve a final PCV of 0.28-0.35. Measurements of PCV allowed calculation of estimated blood losses and transfused volumes in terms of red blood cell mass. Total estimated red cell volume lost was 91 +/- 66% of patient's estimated red blood cell volume during the peroperative period. The type of skull deformation and surgical procedure determined the extent of peroperative bleeding. Peroperative transfusion was satisfactory in 48% of patients and slight overtransfusion was noted in 32%. During the postoperative period, liberal administration of blood led to overtransfusion and possibly unnecessary transfusion in 74% of patients. Because of the well known risks of transmission of infectious disease, strict volume compensation with development of haemodilution and autotransfusion procedures should be used to limit these risks.

[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.

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.

[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.

[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.

[Continuous spectrum analysis during anesthesia and the recovery period in infants under 1 year of age]. / Analyse spectrale continue de l'EEG lors de l'anesthésie et du réveil chez l'enfant de moins de 1 an.

Continuous spectral EEG activity monitoring has been used in adults as a monitor of brain activity during anesthesia. It has not been used in infants. We studied 22 infants less than 7 months old undergoing minor surgery. Halothane alone or minimal Halothane anesthesia associated with caudal epidural anesthesia were used. Life-Scan analysis, in spite of wide individual variations, allowed us to detect infraclinical hypoxia episodes, it provided informations about operative confort, depth of anesthesia and added in the post-operative period an objective criteria to clinical evaluation of pain. A wide use of such a monitoring is warranted in infants.