[Digestive surgery in the elderly]. / Chirurgie digestive du grand âge.

The dramatic increase in digestive surgery among patients of advanced age is the logical consequence of the aging population demographics in developed countries. Surgery in the aged is not fundamentally different, but it demands precise and tailored assessment and management of surgical indications and surgical and anesthetic techniques. Advanced age is not a contraindication to even major digestive surgery, but every effort must be made to avoid urgent operations by attention to pre-existing symptoms which are all-too-often neglected in the aged. Intensive care may help to shorten the hospital stay which should ideally occupy only a minor portion of the numbered days of the patient (whose life expectancy may be significantly longer than one may intuitively foresee).

-Cerebral air embolism after removal of an internal jugular vein catheter-. / Embolie gazeuse cérébrale après retrait d'un cathéter jugulaire interne.

Central venous catheters are usually inserted and manipulated by anaesthetists-intensivists and others familiar with their use under surgical conditions, yet they are often removed on the wards by junior doctors or nurses insufficiently trained in the removal procedure. In order to illustrate the risks presented by such a practice, we report a case of cerebral air embolism following the withdrawal of an internal jugular catheter in a sitting patient. The mechanisms of air entry into the venous and systemic circulation are considered, as well as the preventive and therapeutic measures.

[Syndrome of ovarian hyperstimulation. Report of a severe iatrogenic complication]. / Syndrome d'hyperstimulation ovarienne. Rapport d'une complication iatrogène grave.

Severe ovarian hyperstimulation syndrome is a rare complication of ovulation induction with exogenous gonadotrophins. Severe forms involve acute renal failure, coagulation disorders, massive ascites, pleural effusion and may require pleural and peritoneal puncture. We report a case of severe ovarian hyperstimulation syndrome effectively treated by simple procedures in an intensive care unit.

[Effect of halothane on ventilation and arterial blood gases in rats with and without diaphragmatic paralysis]. / Effets de l'halothane sur la ventilation et les gaz du sang arteriel chez le rat avec ou sans paralysie diaphragmatique.

Some patients with diaphragmatic paralysis or dysfunction maintain ventilation by use of other muscles. Anaesthesia, in modifying the performance of these muscles, presents a potential risk to such patients. To evaluate this risk, the effects of halothane on ventilation and arterial blood gases were studied on a model of bilateral diaphragmatic paralysis, the phrenectomized rat. The study was performed on 43 rats. Success of phrenectomy was confirmed at laparotomy, which did not result in blood gas changes. Laparotomy was performed in 23 rats and a carotid artery was catheterized. In 11 control rats, phrenic nerves were exposed but not sectioned, and in 12 other rats, the phrenic nerves were sectioned. Ventilation was measured by plethysmography in awake rats before and after surgery and in the same rats anaesthetized with halothane 1.1%. In the 23 rats, a decrease in weight and core temperature was observed after operation and this was more marked in phrenectomized than in control rats. In the 11 control rats, ventilation increased postoperatively without change in blood gases. In these rats, halothane caused a decrease in minute ventilation and PaO2 and an increase in PaCO2. Phrenectomy in awake rats led to an increase in minute ventilation, hypoxaemia and hypercapnia. In these rats, halothane led to death in three and a decrease in minute ventilation, with hypercapnia and hypoxaemia in the nine other rats. Blood gas changes were greater than in anaesthetized controls. In the intact rat, halothane leads to blood gas changes comparable to those observed in other species and humans. The present study confirms the effects of halothane on respiratory muscles other than the diaphragm and demonstrates the severe respiratory risk of anaesthesia in patients whose ventilation is maintained by these muscles.

[The effects of halothane on the changes in PaCO2, acid-base equilibrium and ventilation induced by hypoxia in the rat]. / Effets de l'halothane sur les modifications de la PaCO2, de l'équilibre acido-basique et de la ventilation provoquées par l'hypoxie chez le rat.

The effects of progressive hypoxia, obtained by decreasing FIO2 from 0.21 to 0.12, on arterial blood gases and acid-base balance were studied in 13 awake rats and 13 rats anaesthetized with halothane (inspired concentration 1.1%). The effects on ventilation of the decrease in FIO2 from 0.21 to 0.12 were studied in eight rats, awake and then anaesthetized. Halothane causes a decrease in PaO2 and an increase in PaCO2; it abolishes the ventilatory response to hypoxia. The effects of hypoxia on PaCO2 were identical in awake and in anaesthetized rats. In the awake rats, PaO2 decreased from 90.3 +/- 5.9 mmHg to 42.3 +/- 3.6 mmHg, and PaCO2 decreased from 36.7 +/- 3.3 mmHg to 28.1 +/- 1.8 mmHg. In the anaesthetized rats, PaO2 decreased from 78.8 +/- 6.2 mmHg to 34.8 +/- 4.2 mmHg, and PaCO2 decreased from 40.7 +/- 2.8 mmHg to 31.9 +/- 3.7 mmHg. The decrease in PaCO2 during acute hypoxia in the anaesthetized rat could be explained by a decrease in CO2 production, secondary to a decrease in oxygen consumption due to the metabolic and circulatory effects of halothane and hypoxia.

[The effect of halothane on blood gases and arterial acid-base equilibrium in intact rats and in chemo-denervated rats]. / Effets de l'halothane sur les gaz du sang et l'équilibre acido-basique artériels chez le rat intact et chez le rat chémodénervé.

Halothane decreases the ventilatory response to hypoxia and the activity of peripheral arterial chemoreceptors, resulting in "chemical chemodenervation." In order to evaluate the role of this halothane-induced "chemical denervation" in acid-base and arterial blood gas changes, these values were measured in intact and chemodenervated rats, awake and under anaesthesia. Since the depth of anaesthesia could be modified by the anatomical chemodenervation, the ED50 of inspired halothane was determined in six rats before and after anatomical chemodenervation. To prevent haemodynamic changes due to halothane and/or anatomical chemodenervation from interfering with the results, systemic arterial blood pressure and heart rate were measured in six intact rats, awake and then anaesthetized, and in the same rats after chemodenervation, awake and then anaesthetized. In nine intact rats and in 19 chemodenervated rats, arterial pH, arterial bicarbonate concentration, and arterial blood gases (PaO2 and PaCO2) were measured before and after administration of halothane. Anatomical chemodenervation modified neither the inspired ED50 (1.1%), nor the mean arterial blood pressure or heart rate. The haemodynamic effects of halothane were comparable in intact and in chemodenervated rats. Changes in arterial blood gases and acid-base balance due to halothane in intact rats and due to chemodenervation in awake rats were not different, but there was a decrease in PaO2 and pHa, and an increase in PaCO2. In chemodenervated rats, halothane caused a further decrease in PaO2 and a further increase in PaCO2. The fact that halothane and anatomical chemodenervation have similar effects on arterial blood gases and acid-base balance favours a "chemical chemodenervating" action of halothane. However, the additional effects of halothane in the anatomically chemodenervated animal show that the action of halothane on blood gases and acid-base balance is the result of multiple sites of impact on the respiratory system.

[Respiratory effects of moderate hypothermia (36 degrees C-28 degrees C) in dogs under halothane anesthesia]. / Effets ventilatoires d'une hypothermie modérée (36 degrees C-28 degrees C) chez le chien anesthésie à l'halothane.

Changes in systemic haemodynamic variables (mean arterial pressure, MAP; heart rate, HR; cardiac output, Qc), in oxygen consumption, VO2, and in ventilation (minute ventilation, V; respiratory frequency, f; tidal volume, VT; and arterial blood gases) with particular attention to respiratory times (duration of inspiration, TI; duration of expiration, TE; duration of the breathing cycle, TTOT), to respiratory timing (TI/TTOT) and respiratory drive (VT/TI) were studied during moderate progressive hypothermia (36 degrees C to 28 degrees C) during stable halothane anaesthesia (MAC = 1.5) in six dogs. MAP, HR and Qc decreased; V and f decreased, the decrease in f being correlated with that in temperature (r = 0.66; P < 0.01). Tidal volume did not change. The PaO2 and pHa decreased while PaCO2 increased slightly. The decrease in ventilation was related to changes in respiratory times (TI and TE) which increased (TE more than TI) and in respiratory drive (VT/TI which decreased due to the increase in TI). The relation between VT/TI and TI/TTOT changes was not constant during cooling. Changes in respiratory times and drive could be due to the effect of cold on medullar respiratory control.

[Evaluation of epidural analgesia. Analysis of a prospective questionnaire answered by 100 women who delivered with epidural analgesia]. / Evaluation de l'analgésie péridurale. Analyse d'un questionnaire prospectif chez 100 femmes ayant accouché sous analgésie péridurale.

An enquiry was carried out by sending 368 women a double questionnaire at the eighth month of pregnancy and after delivery, in order to assess their opinions and motivations as far as epidural anaesthetic was concerned, and how far their expectations had been fulfilled. One hundred forms were returned. The sample was: 64% primipara and 36% multipara, of whom 64 women were married, 27 living in a stable relationship and 9 living on their own. 85% had a profession and 52% were in a higher social category. Eighty two of the women asked for an epidural in order to: in 58% of cases participate in their delivery, and in 31% of cases bond with the child. 57% hoped for less pain rather than for complete absence of pain which was asked for in 43%. Of the 36 multipara, 34 asked for epidural analgesia. Those who refused to have an epidural thought that they would be able to live through the delivery in a more natural way (44%) and 52% thought the process had become too medicalized and that complications of a medical nature might supervene. 33% gave no reason for refusing. This group contained more primipara (16) than multipara (2). These primipara thought that epidural analgesia would stop them taking part in the delivery and 10 of these knew that they would have pain in the delivery. Post partum replies showed that 58% had a higher opinion of epidural after than before the delivery and 93% were highly satisfied with the analgesia that they received. This despite the fact that the techniques were not perfect. Seven women thought the procedure unsatisfactory although there were no technical faults but the enquiry showed that they expected more from epidural analgesia. Whether they were satisfied or not, 98% of the women said that they would ask for epidurals in subsequent deliveries.

[Addition of a morphinomimetic to the continuous perfusion of 0.125% bupivacaine for peridural obstetrical anesthesia. A comparative study of fentanyl and alfentanyl]. / Adjonction d'un morphinomimétique à la perfusion continue de bupivacaïne 0.125% pour l'analgésie péridurale obstétricale. Etude comparative fentanyl-alfentanil.

Morphinic drugs added to epidural local anesthetic during labour enhance analgesia and obstetrical conditions. Fentanyl, 1 microgram/kg-1, is safe for the newborn. Alfentanil is of faster and shorter duration and its pharmacokinetics suggests less accumulation than fentanyl. The aim of this study is to compare Alfentanil versus Fentanyl when added to an epidural continuous bupivacaine 0.125% infusion. Two groups of parturients are constituted: group A 10 micrograms/kg alfentanil, group F 1 microgram/kg fentanyl. Pain is assessed with a 0 to 10 points scale. There are no differences between the two groups for age, weight, parity, term, initial cervical dilatation and new born weight. Analgesia begins quickly in the two groups, and is more pronounced in the group A (than in the group F (p less than 0.005). Analgesia is maintained for the whole dilatation course. Pain scores increase during expulsion but are significantly lower than the initial scores. No difference is noted as regards analgesia supplementation. Obstetrical data: labour duration, oxytocin dosage, expulsion strength, instrumental extraction rate and uterin evacuation are similar in the 2 groups. No cesarean section is observed. Neonatal status, established according to Apgar scores and then Amiel Tison neurological scales (0 to 30) respectively at 30 to 120 minutes are in the same favorable ranges: Apgar score is in all cases more than 9. The neurological score is 24 (group A) and 22.9 (group F) at 30 minutes and increases significantly at 120 minutes in the 2 groups (27 in the two groups).(ABSTRACT TRUNCATED AT 250 WORDS)

A comparison between propofol and ketamine for anaesthesia in the elderly. Haemodynamic effects during induction and maintenance.

The haemodynamic effects of propofol and ketamine were studied in two groups of eight randomly allocated elderly patients (mean age 85.8 years) anaesthetised for hip replacement. Group 1 patients patients received propofol 1 mg/kg by intravenous bolus for induction and 0.1 mg/kg/minute by continuous infusion for maintenance. Group 2 patients received ketamine 1.5 mg/kg by intravenous bolus as induction dose and 50 micrograms/kg/minute by continuous infusion for maintenance. All patients breathed spontaneously via a facemask at FIO2 1.0. Haemodynamic status was established before induction and at 1, 3, 5, 10 and 15 minutes after induction. Arterial pressure and cardiac output decreased slightly in group 1 but heart rate, right atrial pressure and pulmonary arterial pressure remained unchanged. Myocardial oxygen consumption showed a significant decrease of 27%. There was a significant increase in blood pressure and pulmonary capillary wedge pressure (by 97%) in group 2. Cardiac output and systemic vascular resistance remained unchanged whereas myocardial oxygen consumption showed a very significant increase of 100%.

The arteriovenous fistula in segmental pancreatic transplantation in dogs--a hemodynamic study.

Arterial and/or venous thrombosis is a frequent complication in experimental or human pancreatic transplantation. A canine experiment was used to study the hemodynamic effects of spleno-splenic arteriovenous fistula during segmental pancreatic transplantation. An increase in blood flow, without "steal" syndrome in the pancreatic blood supply or pressure increase, was found. Thus this technique can help prevent vascular thrombosis in pancreatic transplant in dogs.

[Fentanyl in peridural obstetrical analgesia. Evaluation after 4 years' use]. / Le fentanyl dans l'analgésie obstétricale par voie péridurale. Bilan après quatre ans d'utilisation.

7,500 deliveries occurred from the date of opening of the Maternity Hospital Jean-Rostand. 3,500 of these were conducted under epidural anaesthesia. At different stages prospective studies were carried out to recall the effect of adding fentanyl to bupivacaine when the epidural injection was made. A pharmacokinetic study. This shows that the levels in the mother and the fetus begin to coincide more with the number of doses that are given and pass from 0.3 after 50 micrograms have been administered to 0.5 after 100 micrograms have been administered and 0.7 after 150 micrograms have been administered. The fetal levels are far lower than those required to depress respiration. The half life of distribution through the circulation has been worked out at 4 minutes and the half for elimination of the drug at 460 minutes. The maternal levels show great fluctuations and late alterations. Analgesia is earlier, more complete and more prolonged when fentanyl is added. Fentanyl also masks irregularities. Undesirable effects such as tiredness, pruritus, nausea, vomiting and urinary retention occur infrequently and last only for short periods of time. No mother had respiratory depression. The doses of bupivacaine that had to be given were as a whole less when fentanyl was added. In 40% of cases it only required one injection to achieve analgesia throughout the whole labour. The length of labour and the number of caesarean operations carried out did not change.(ABSTRACT TRUNCATED AT 250 WORDS)

[Propofol or ketamine in anesthesia of the very old patient. Study of the hemodynamic effects during induction]. / Propofol ou kétamine pour l'anesthésie du grand vieillard. Etude des effets hémodynamiques à l'induction.

The haemodynamic changes following anaesthesia for hip surgery in 16 very old ASA II or III patients (mean age 85.8 +/- 5 years) were studied. Patients were randomly assigned to two groups: group I 1 mg X kg-1 propofol, group II 1.5 mg X kg-1 ketamine. After injection, the patients were left spontaneously breathing oxygen, and were assisted when apneic. Haemodynamic measures with a Swan-Ganz catheter and thermodilution cardiac output calculator were made before and 1, 3, 5, 10 and 15 min after anaesthetic induction. The two groups were similar in age, weight and mean arterial pressure, but statistically different for some haemodynamic parameters (Ppa, Ppw, CI). In group I, arterial pressure fell significantly (-17%) in the first minute and continued to fall (-15%) until the 15th min. Heart rate remained unchanged: right atrial and pulmonary pressures were not changed; cardiac index fell slightly and MVO2 estimated by the triple product fell (-27%) as soon as propofol was infused. There was no clinical sign of cardiac failure. In group II, arterial pressure increased significantly, and heart rate decreased; pulmonary capillary wedge pressure increased (+93% after the 3rd min) and cardiac index was unchanged. The ventricular function curve was shifted to the right, suggesting a decrease in inotropism. Systemic vascular resistances were steady. MVO2 increased twofold, mainly due to the rise in pulmonary capillary wedge pressure.(ABSTRACT TRUNCATED AT 250 WORDS)