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Objective: To describe the perioperative management, from the point of view of the anesthesia-intensive care unit specialist, of patients with aortic stenosis who undergo transcatheter aortic valve implantation (femoral or apical TAVI)., Data Source: The PubMed database (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi) was queried, using the following keywords: aortic stenosis, transcatheter aortic valve implantation TAVI, outcome, complications, anesthesia., Data Synthesis: TAVI is performed in patients suffering from aortic stenosis and presenting with numerous comorbidities, high-predicted perioperative mortality and/or contraindications to conventional cardiac surgery. TAVI is performed either by percutaneous transfemoral or transapical puncture of the left ventricle (LV) apex. These patients are older, have more comorbidities than those undergoing aortic valve replacement surgery and perioperative mortality predicted by risk scores is higher. While transapical TAVI is performed with general anaesthesia, transfemoral TAVI can be performed with either general or locoregional anaesthesia and/or sedation. The choice of the anaesthetic technique for transfemoral TAVI depends on the patient's medical history, the technique chosen for valve implantation, the type of monitoring and the anticipated hemodynamic problems. The incidence of complications following TAVI is high, some are common to surgical aortic valve replacement, and others are specific to this technique. Because of the prevalence of comorbidities, the hemodynamic-specific constraints of this technique and the incidence of complications, anaesthetic and perioperative management (evaluation, anaesthetic technique, monitoring, post-surgery care) requires the same level of expertise as in cardiac surgery anaesthesia., Conclusion: TAVI expands treatment options for patients with aortic valve stenosis. The anaesthesia team must be involved in the care of these patients with the same level of expertise and care as in heart surgery on critical patients., (2011 Elsevier Masson SAS. All rights reserved.)

Unlabelled: This article reviews the development of STANDARDS, Recommendations and Guidelines for practice in anaesthesiology in France and other countries. The French society for anaesthesia and intensive care (Sfar) has published, since 1989, 11 basic, Standards: 1) Recommendations for the monitoring of patients during anaesthesia (June 1989, amended on January 1994) [APSF Newsletter, Summer 1990, page 22]; 2) Recommendations for postanaesthesia monitoring and care (September 1990); 3) Recommendations for preanaesthesia care (September 1991); 4) Recommendations for anaesthetic apparatus and checking before use (January 1994); 5) Recommendations for the equipment of anaesthesia working places (January 1995); 6) Recommendations for the tasks of the nurse anaesthetist (January 1995); 7) Recommendations for hygiene standards in anaesthesia practice (December 1997); 8) Recommendations for outpatient anaesthesia (September 1990); 9) Recommendations for the practice of obstetrical analgesia (September 1992); 10) Recommendations for interhospital physician-accompanied transfers (December 1992); 11) Recommendations for intrahospital physician-accompanied transfers (February 1994). Additionally the Sfar produced or coproduced 9 Experts' conferences, 15 Consensus conferences and 5 Guidelines for clinical practice.

Objectives: To display theorical and methodological basis of the molecular biology. To point out its main medical applications., Data Sources: For this review, we analysed the English and French literature concerning the research and clinical aspects of the molecular biology, especially in anaesthesiology and intensive care, using the Medline database. The current textbooks were also used., Study Selection: We selected: 1) the original articles corresponding to the main advances that resulted in the present state of this discipline; 2) the reviews; 3) some chapters of textbooks., Data Extraction: In this review, we report: 1) the current knowledge concerning the conservation and the expression of the genome; 2) the principles of the most widely used experimental techniques; 3) the medical applications of this knowledge in anaesthesiology and intensive care; 4) the more recent developments of this research field., Data Synthesis: Within medical biology, molecular biology essentially corresponds to the study of nucleic acids. In this review, the general principles governing the organization and expression of the genome are discussed. The expansion of molecular biology has been a consequence of the widespread use of enzymatic tools, of which bacterial restriction enzymes were the first. Numerous enzymes are now available, permitting DNA strands to be cut, linked, synthesized and sequenced. Several of the most representative molecular biology techniques are described. Some of them, such as PCR, are commonly used in clinical situations. Animal experimental models have also been generated by genome altering methods, in order to analyse the phenotypic consequences of these modifications. Recently, a viable mammal, deriving from a differentiated cell, has been cloned. Human embryonic totipotent stem cells are now available in cultures. These advances have important ethical implications whilst, at the same time, offering new opportunities for medical applications. The state of gene therapy and human genome sequencing programmes is discussed.

The reporting of the first death attributed to anaesthesia is commonly placed in 1848. The present work indicates that, in France, anaesthesia was recognized as being responsible for deaths as early as February, 1847.

Penetrating cardiac injury has to be ruled out in any patients with penetrating thoracic injuries, even in those with no alterations in vital functions. Undelayed echocardiography should be performed to screen for the presence of pericardial effusion. The first case underlines the risk of cardiac tamponade if the diagnosis is missed. Echocardiography was not performed because no echocardiographist was present at the time, and a high suspicion of a neck vascular injury existed. Sudden deterioration due to the onset of acute tamponade was only reversed by an immediate pericardiocentesis followed by surgical haemostasis. The second patient, although stable, had a large echographic pericardial effusion. Emergent sternotomy revealed a large amount of blood in the pericardial space and two cardiac wounds with one on a coronary artery. Penetrating wounds in proximity to the heart, even in a stable patient, require aggressive attempts at ruling out a cardiac injury. Immediate echocardiography should be systematically performed to screen for pericardial fluid.

Objective: To compare the effects of a sedative dose of midazolam on mean inspiratory flow (VT/TI = index of central respiratory activity), known as being decreased by midazolam and the intercostal muscle activity, known as being increased by this agent., Study Design: Laboratory study., Patients: Seven healthy volunteers., Methods: After assessment of baseline values of ventilatory variables and intercostal electromyographic activity (in arbitrary units), midazolam 0.1 mg.kg-1 was administered by iv route. The measurements were repeated after 5 and 10 min, and finally 2 min after the i.v. injection of flumazenil 1 mg., Results: Midazolam decreased VE and VT. Similarly VT/TI ratio decreased from 0.44 +/- 0.04 (baseline value) to 0.26 +/- 0.03 (5 min) and 0.3 +/- 0.03 L.s-1 (10 min later) respectively (P < 0.05). Conversely, midazolam increased the intercostal electromyographic activity from 4.0 +/- 0.7 (baseline value) to 26.5 +/- 16.6 (5 min) and 28.4 +/- 16.6 U (10 min later) respectively (P < 0.05). Within 2 min after flumazenil administration all variables returned to baseline values., Conclusions: The decrease of VT/TI ratio is probably linked to increased resistances in the upper airways. This ratio cannot act as an indicator of respiratory drive during sedation or anaesthesia. The assessment of the ventilatory effects of benzodiazepines must be based simultaneously of the various other indicators of the ventilatory drive, as these agents act on the different stages of the ventilatory cycle and therefore cannot be characterized by a unique variable.

Objectives: The predictive value of APACHE II and SAPS severity scores were evaluated in a group of patients with acute renal failure admitted in ICU after emergency surgery. The criteria of poor prognosis identified in the 24 hours following admission were also evaluated., Study Design: Open prospective study., Patients and Methods: During 22 months, we included every patient admitted in ICU after emergency surgery with a serum creatinine concentration > or = 130 mumol.L-1. Clinical and biological parameters were collected in the first 24 hours following admission and the severity scores were calculated. Prediction of hospital outcome, based on APACHE II score, was calculated. The standard mortality ratio (observed mortality/predicted mortality) was calculated. Accuracy of SAPS and APACHE II score was compared using ROC curves and comparison of the areas under the curves., Results: Death in ICU occurred in 44% of the patients while hospital mortality was 51%. The standard mortality ratio for APACHE II score was 1.35. The areas under the curves for SAPS and APACHE II scores were not statistically different. The criteria of poor prognosis, identified in the first 24 hours following admission, were cardiovascular failure, oliguria and sepsis., Conclusion: Conventional severity scores are inaccurate for prediction of mortality in patients with acute renal failure following emergency surgery.

A 78-year-old man with a history of hypertension was admitted for a fall with back pain. The blood pressure was at 110/50 mmHg and the pulse at 115 b.min-1. A pulsatile abdominal mass was palpated. No signs of respiratory insufficiency or congestive heart failure were found. The diagnosis of abdominal aortic aneurysm was promptly confirmed by echography. Before laparotomy, a pulmonary artery catheter was inserted for haemodynamic monitoring which showed a high cardiac output, low systemic vascular resistances, increased pulmonary artery wedge pressure and a high SvO2 (93%). This was not consistent with a hypovolaemic shock but rather an aortocaval fistula. After incision and aortic clamping, surgical procedure consisted of transaortic closure of the fistula and restoration of arterial continuity with a prosthetic graft. Initial control of venous bleeding was obtained by passing a Foley's catheter distally and by clamping the vena cava. The postoperative course was initially satisfactory. The patient was extubated, but remained with a major renal insufficiency. After a stay of 15 days in the intensive care unit, he died from nosocomial pneumonia. Aortocaval fistulas are either traumatic or spontaneous. Spontaneous fistulas are more common, and in about 90% of the cases result from a rupture of an atherosclerotic aortic aneurysm. Clinical findings include signs of high cardiac output symptoms of venous hypertension and regional arterial insufficiency. Haemodynamic changes can be of value for the recognition of an aortocaval fistula. Most authors emphasize the importance of preoperative diagnosis, allowing the use of appropriate operative techniques and a prompt control of the fistula. This could decrease haemodynamic instability and transfusion requirements.

Acute alcohol intake may be of potential hazard in anaesthesia emergency procedures because of consciousness alterations. Alcohol ingestion alters indeed the functions of upper airway muscles and increases the risk of obstructive sleep apnea. However, no data are available on the effects of alcohol on the swallowing reflex (SR), which is a major protective mechanism against pulmonary inhalation and on upper airway resistances (UAR) following external inspiratory load application. This study was designed to investigate the effects of acute alcohol intake on SR and UAR in healthy volunteers. After informed consent, 8 male volunteers (29 +/- 3 years) were studied in the supine position. The tip of a catheter was placed through the naris at the epipharynx level for injection of 3 series of 2 volumes of distilled water (0.25 and 1 ml respectively). Swallows were identified by a submental electromyogram. SR efficiency was assessed by recording 1) the latency (L) between injection and the first swallow, and 2) the number of swallows (N) elicited by each bolus. The subjects were breathing through a facial mask connected to a pneumotachograph. Supraglottic airway pressures (UAP) were recorded using a small balloon catheter placed at the tip of the epiglottis. UAR were calculated as the ration of UAP (cmH2O) on air-flow (l.s-1) at the airflow's peak. After a control set of measurements (TC), including SR assessment and UAR at rest (UARo) and during application of an external inspiratory resistive load (12 cmH2O.l-1 x s-1) (UARr) to sensitize the experiment, the subjects ingested 1 ml.kg-1 of alcohol as 40 degrees vodka.(ABSTRACT TRUNCATED AT 250 WORDS)

In order to assess the medical activity and the related costs, the French Ministry of Health has designed a relative value scale for medical procedures, the Relative Complexity Index (RCI). The RCI for anaesthesiology, called BETA, is the result of the combination of four subindexes: T for the type of anaesthesia, D for the duration, C for the related surgical procedure, and EG for the patient's status according to the ASA scale. The goal of this study has been to test whether the BETA index was actually an acceptable indicator of the direct cost of an anaesthetic. We have determined the cost of 248 procedures in a teaching hospital and achieved a statistical analysis of the relationship between costs, RCI and the various subindexes. The mean cost of an anaesthetic was 1,205 FF (SD = 1,325), 61.4% of which being for salaries. The cost of a general anaesthetic was 2.5 times higher than the cost of a local/regional anaesthesia procedure. Mean cost was around 700 FF for ENT, urology, gynaecology and obstetrics, 1,200 FF for orthopaedia and visceral surgery, and 5,130 FF for cardiac surgery (not including the equipment for extracorporeal circulation). A strong positive relation was found between the BETA and cost (r = 0.90, p < 10(-4)). The best predictive model of cost was log-linear, using only the duration, the type of anaesthetic and the related surgical procedure. The patient's status was not a significant factor, nevertheless in our sample, ASA 4 patients had a significantly higher cost than others (p = 0.0004, Mann & Whitney test).(ABSTRACT TRUNCATED AT 250 WORDS)

This study was designed to assess the swallowing reflex after an endotracheal intubation of more than 24 h, as well as the influence of age and duration of intubation on swallowing. Twenty patients (aged 58 +/- 17 years) who had been intubated for more than 24 h were compared with fifteen others (63.1 +/- 16.7 years), who had never been intubated. All had a nasogastric tube. Swallowing was assessed after administration of 0.25, 0.5, 0.75 and 1 ml volumes of normal saline, in a random sequence, into the epipharynx through a thin catheter passing through the nostril after extubation (E0), and then at 1 (E1), 8 (E8), 24 (E24) and 48 h (E48) in the extubated patients, and once in the control patients. Swallowing responses were identified by an electromyogram of the floor of the oral cavity. The efficiency of the swallowing reflex was assessed by the delay between instillation and the first swallowing response obtained, and the number of swallows recorded during the first 15 seconds following each injection. There was a significant increase in swallowing delay in intubated patients for volumes less than 1 ml during the first three measurements. Recovery occurred for 0.5 and 0.75 ml at E24 and E48, when compared with the control group. However, delay remained increased throughout the study for 0.25 ml. The number of swallows was the same in both groups for each volume tested. There was no correlation between increased delay and age or duration of intubation. These data confirmed that prolonged endotracheal intubation impairs the swallowing reflex.(ABSTRACT TRUNCATED AT 250 WORDS)

A study was carried out to compare the haemodynamic and respiratory effects, as well as the quality of recovery, of anaesthesia with ketamine, sodium gamma-hydroxybutyrate (GOH) and etomidate in children undergoing cardiac catheterization. Thirty children, mean age 48 +/- 35 months, ranked ASA 2 or 3 on account of congenital heart disease, were assigned to one of three groups (n = 10). They were given: in group E1, a 0.3 mg.kg-1 bolus of etomidate, followed by 0.1 mg.kg-1.min-1 for 10 minutes, and 0.026 mg.kg-1.min-1 thereafter; in group G2, a 50 mg.kg-1 bolus of GOH, and in group K3, a 4 mg.kg-1 bolus of ketamine followed by a continuous infusion of 0.083 mg.kg-1.min-1. The patients breathed spontaneously. Monitoring included heart rate, systolic, diastolic and mean blood pressure, pulse oximetry, and capnography. Femoral venous or arterial catheterization was performed after local anaesthesia (with no more than 2 mg.kg-1 of lidocaine). Measurements were performed before induction, and then 1, 10, 30 and 60 minutes afterwards. The quality of anaesthesia was assessed according to Steward's scale. The investigation lasted between 50 and 100 min in all three groups. There were no significant differences in haemodynamic and respiratory parameters during the investigation between the groups. Recovery was shorter and of better quality in group E1. On the opposite, 30 minutes after the end of the catheterization, all the patients in group K3 were stuporous, with 5 of them displaying involuntary movements. The patients of the other two groups reacted correctly to stimuli, but those in group G2 went back to sleep very rapidly. There were no complications.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of a continuous steady rate infusion of propofol on spontaneous ventilation were studied in eight unpremedicated ASA 1 male patients. All were non smokers, aged 29 +/- 8 years, and weighed 67 +/- 9 kg. After an initial 1 mg.kg-1 bolus, they received 10 mg.kg-1.h-1 propofol for 10 min, followed by 8 mg.kg-1.h-1 for a further 10 min, and then 6 mg.kg-1.h-1 during the whole study period. Endotracheal intubation was carried out using lidocaine for local anaesthesia. Spontaneous ventilation was assessed during three periods of five minutes: in the awake subject, using indirect spirometry (measurement of variations in chest circumference) and direct spirometry separately, and then, in the anaesthetized subject, using both methods simultaneously. This study aimed: a) to compare the results obtained with the two methods, b) to characterize the effects of propofol anaesthesia on chest wall mechanics using the partitioning of ventilation between rib cage and abdomen provided by the non-invasive method, and c) to assess abdominal compliance by means of a gastric balloon catheter. There was an increase in rib cage ventilation in the awake state, induced by the apparatus for direct spirometry (mouth piece, nose clip). This explained that the ventilatory depression induced by propofol anaesthesia was more pronounced when measured by the direct method. The major determinant of this depression was a shortened inspiratory time, and, to a lesser extent, a decreased mean inspiratory flow rate. By contrast to inhalational anaesthesia, rib cage ventilation was preserved during propofol anaesthesia. The decrease in abdominal ventilation was partly related to a lowered abdominal compliance, suggesting recruitment of the abdominal muscles.

This study was designed to investigate the effects of halothane on the electrical activity of the respiratory muscles in rats. Indeed, halothane is known to reduce end-expiratory lung volume, both in man and in animal; this may be due to altered activity in the respiratory muscles. The electrical activity of the diaphragm, parasternal, intercostal and abdominal muscles were recorded using intramuscular electrodes in ten rats weighing between 400 and 450 g each. The rats were prepared under light halothane anaesthesia (tracheostomy, laparotomy, electrode positioning, plaster of Paris cast to impede leg movements). They were placed prone in a 20 1 plexiglass chamber, and allowed to awake. Thereafter halothane was vaporized in this chamber at a known concentration, until the animals no longer reacted to tail pinching. The measurements were carried out during the awake state, and under 2 vol % halothane. Muscle tone was assessed by the thickness of baseline inspiratory muscle activity at the end of expiration (maximally amplified raw electromyographic signals). The measurement of phasic electrical activity was carried out using peak inspiratory integrated electromyographic signals. Under halothane, phasic activity of the diaphragm was slightly reduced (p less than 0.05), whereas tonic activity remained unchanged. Parasternal intercostal muscle activity, both tonic and phasic, was also decreased during halothane anaesthesia (p less than 0.001). No phasic activity occurred in the abdominal muscles, but muscle tone was reduced during halothane administration (p less than 0.01). In rats, the decrease in intercostal muscle tone under halothane anaesthesia could play a major part in the fall in functional residual capacity.(ABSTRACT TRUNCATED AT 250 WORDS)

This prospective study aimed to assess the quality of interpretation by Teaching Hospital anaesthesiologists of preoperative electrocardiograms (ECG). It was carried out over a period of 7 months, and included 500 patients scheduled for elective surgery. The ECG was first interpreted by the anaesthesiologist during the preoperative visit, and later during the postoperative period, by a cardiologist. The two interpretations were compared using the following criteria: minor anomalies, which would not influence the anaesthetic technique already selected; major anomalies, which, on the other hand, are known to increase anaesthetic morbidity and mortality rates, thereby influencing the choice of anaesthetic technique; and interpretative errors concerning only the major anomalies, i.e. anomalies not seen by the anaesthesiologist (false negatives), anomalies found which did not exist (false positives), and erroneous or incomplete interpretation. Interpretation of the ECG by the anaesthesiologist was written on the anaesthetic record for only 156 patients (31.2%). Among the 500 ECG's, 141 were found to be abnormal by the cardiologist (28.2%). Seventy-three of them had 1 or more major abnormalities. Of the 156 ECG's interpreted by an anaesthesiologist, 64 (41%) were abnormal. The overall error rate was 21.1%, the major error rate being 7.1%. The overall false negative rate was 12.8%, with 7 major ischaemic abnormalities (4.5%) having not been found, including 4 (2.6%) diagnostic errors. About 3.8% of ECG's were wrongly interpreted as abnormal by the anaesthesiologist; all errors were of minor importance, but nevertheless responsible for delayed surgery, loss of time, and extra expenditure in laboratory tests.(ABSTRACT TRUNCATED AT 250 WORDS)

This open, non comparative study was designed to establish a suitable dose regime for propofol when used as the main anaesthetic agent and given as a continuous infusion. Thirty patients (ASA I and II) were studied; five received muscle relaxants and were excluded from the analysis of maintenance and recovery. Immediately after an i.v. bolus dose of fentanyl (2 micrograms X kg-1), anaesthesia was induced in all patients with a mean dose of 2.03 mg X kg-1 propofol. Apnoea at induction was seen in 14 patients, with a mean duration of 151 s (range: 20 to 360 s). Mean, systolic and diastolic arterial pressures and heart rate decreased slightly but statistically significantly following induction. Fourteen patients, four of whom received propofol into a vein of the hand, noted pain on the injection site without venous sequelae immediately nor 24 h after anaesthesia. The mean duration of anaesthesia from induction to the patient ability to obey a simple command was approximately 40 min (range: 10 to 95 min). The mean infusion rate of propofol during maintenance was 0.86 +/- 0.04 mg X kg-1 X min-1. During maintenance, a satisfactory depth of anaesthesia was achieved in 23 patients without any further bolus injection of propofol. The mean time from stopping the infusion to eye opening on verbal command was 6.2 min, whilst that for orientation was 8.4 min. The anaesthesist assessed the quality of recovery as good or adequate in all the patients, who all were satisfied by the anaesthesia. No major adverse reactions occurred during or after anaesthesia and the incidence of minor side-effects was low.

Preoperative measurement of blood volume was performed in 35 patients undergoing coronary arterial bypass grafts. The patients were divided in two groups according to the preoperative blood volume measurement : normal (group I) and decreased (group II) blood volume. Cardiac filling pressures were measured with a Swan-Ganz catheter prior to induction of anaesthesia in all patients. Pulmonary capillary wedge pressure was significantly decreased in patients with diminished blood volume. Clinical data was compared between the two groups. No differences were found regarding preoperative cardiovascular drugs and severity of coronary arterial disease. The only differences between the two groups were : 1) the length of preoperative hospitalization was significantly longer for hypovolaemic patients (21 +/- 10 days) than for normovolaemic patients (3 +/- 6 days); 2) more group II patients (13 of 15) received a salt-restricted diet than group I patients (2 of 20). Diet induced hypovolaemia may increase the rate of large haemodynamic variations produced by induction of anaesthesia in patients with coronary arterial disease. Seeing the frequency of preoperative hypovolaemia in patients undergoing coronary arterial surgery, we recommend the preoperative measurement of blood volume in these patients and preanaesthetic fluid replacement when hypovolaemia is present.

The effects of enflurane on systemic vascular resistance and venous capacitance, and its biotransformation during hypothermia, were studied in patients undergoing cardiovascular surgery with enflurane anaesthesia. When administered during cardiopulmonary bypass (CPB), cardiac regulatory mechanisms being therefore excluded, enflurane induced an arteriolar vasodilation related to the concentration inhaled. An inspired concentration of 2.5% in hypothermia (28 degrees C) produced a drop in systemic vascular resistance of 30% from control level. In the same conditions, venous capacitance was not altered. The rise in the blood gas solubility coefficient during hypothermia was only partly balanced by haemodilution. Therefore, inspired enflurane concentration should be higher during hypothermic CPB than during normothermic anaesthesia to obtain the same effects. For the same amount of enflurane inhaled, the fraction of enflurane metabolized was higher in hypothermia than in normothermia, but the inorganic fluoride plasma concentration at its highest never reached the level of 50 mumol X 1(-1) regarded as the nephrotoxic threshold.

The usual anterior and lateral routes used for superior laryngeal (SL) nerve blocks are not often used because too difficult to carry out. A simpler and easier technique is described, which blocks the SL nerve at the level of the greater cornu of the hyoid bone. Because the nerve is not located accurately with this technique, a larger volume of local anaesthetic is required. This technique was tested in 31 patients scheduled for endoscopies with rigid tubes. The mean duration of endoscopy was 30 +/- 10 min. The use of 8 ml 1% lidocaine for the block 30 min surgical anaesthesia. In 2 patients, the SL nerve block alone was sufficient. In 26 others a complement with a benzodiazepine (flunitrazepam, n = 9, mean dose 0.8 mg; midazolam, n = 17, mean dose 5 mg) was required. In 4 of these patients, attempts of oesophagoscopy gave rise to hypertension and tachycardia. General anaesthesia with propofol and tracheal intubation were therefore used. In the last 3 patients, intercricothyroid jet ventilation was used, requiring general anaesthesia (propofol and succinylcholine). The SL nerve block was satisfactory in 24 patients with total vocal cord paralysis and no haemodynamic reaction to painful stimuli in the blocked area. No complication was observed. It is concluded that this technique is useful and easier to carry out than the usual ones.

Sixty difficult radial artery cannulations were carried out using either the Seldinger technique (Seldicath Plastimed, FG 3, 80 mm long; group S; n = 30) or a new arterial catheter (Arrow, Critikon, gauge 20, 44 mm long; group A; n = 30) in patients scheduled for coronary arterial surgery or cardiac valve replacement (age: 54.8 +/- 11.8 yr). The technique was chosen at random after failure of radial artery catheterization with a short intravenous catheter (Quick-Cath Travenol, gauge 20, 31 or 51 mm long, or Insite W Beckton-Dickinson, gauge, 20, 30 mm long). The second attempt was carried out on the same artery, a few centimeters higher up than the first one. Heparinized normal saline was infused through this arterial line. All the catheters were removed after extubation. There was no arterial thrombosis, nor any displacement of the catheter with loss of the arterial pressure curve. No difference was found between the two techniques regarding the number of catheterization failures, the duration of cannulation, and the quality of the blood pressure curve. For difficult radial artery cannulations, the arterial catheter Arrow associated the advantages of the Seldinger technique with those of short intravenous catheters.

Because sufentanil has been reported as being able to prevent or treat peroperative hypertensive crises during aorto-coronary artery graft surgery, a study was carried out to compare the haemodynamic effects of sufentanil with those of fentanyl. 20 patients who were to undergo aortocoronary bypass grafting (CABG) were randomly allocated to two equal groups, sufentanil (Sf) and fentanyl (F) groups. A 1 to 5 dose ratio was used so as to have equipotent doses of sufentanil and fentanyl. Induction doses were 10 micrograms.kg-1 sufentanil and 50 micrograms.kg-1 fentanyl. Up to 20 micrograms.kg-1 sufentanil and 100 micrograms.kg-1 fentanyl were then used between intubation and the setting-up of cardiopulmonary bypass (CPB). A bolus of 10 micrograms.kg-1 flunitrazepam was given if necessary, so as to lower the mean arterial pressure (Pa) to below 100 mmHg after intubation, and under 80 mmHg during CPB. Heart rate, Pa, mean pulmonary arterial pressure, pulmonary wedge pressure (Ppw), central venous pressure and cardiac output were measured before anaesthesia, 2 min after intubation, before incision, 2 min after sternotomy, 10 min after the end of CPB, after chest closure, 30 min and 2h after arrival of the patient in the intensive care unit. The only difference found between the two groups was a more rapid drop in left ventricular preload after induction with sufentanil; 2 min after intubation, there was a 26% fall in Ppw with sufentanil (p less than 0.01) and 8% with fentanyl. Before skin incision, this drop was of 32% (p less than 0.01) and 24% (p less than 0.01) respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Reversal of benzodiazepine-induced sedation by flumazenil has been reported to produce no or minor hemodynamic alterations although some adverse responses have been observed. To better delineate circulatory and adrenergic modifications induced by flumazenil, 20 consenting patients scheduled for short orthopedic procedures were included in a double blind controlled study. Anesthesia consisted in flunitrazepam (30 to 40 micrograms.kg-1) plus halothane (0.5 vol. % in N2O-O2, 60-40 vol. %) and alfentanil. At the end of surgery, patients received 15 minutes after discontinuation of halothane and N2O, either flumazenil (1 mg) or placebo according th randomization. Heart rate and blood pressure were obtained before reversal and repeatedly for 30 minutes following flumazenil or placebo. Level of consciousness was also assessed and blood samples were withdrawn for subsequent determination of plasma levels of norepinephrine. Flumazenil administration induced in all cases an immediate and total reversion of sedation while recovery was slow in the placebo group. No significant changes in heart rate and blood pressure values were found in both groups. By contrast, plasma levels of norepinephrine were significantly increased in all patients. It is concluded that reversal of benzodiazepine-induced sedation or anesthesia is not associated with significant variations of usual hemodynamic or adrenergic responses.

The equipment available for mixed venous blood saturation (Svo2) monitoring is now accurate. SvO2 is not a direct measure of cardiac output, because it depends on the balance between oxygen delivery (TaO2) and consumption (VO2). As haemoglobin affinity for oxygen increases during cardio-pulmonary bypass (CPB), the optimal level of SvO2 after CPB should be above 65-70%. There is a critical level of TaO2 below which VO2 is dependent on TaO2. Below this level, SvO2 has no clinical value as it no longer depends on TaO2. Similarly, SvO2 has no clinical value during lactic acidosis. When these limitations are taken into account, SvO2 monitoring is useful for the interpretation of intra- and post-operative haemodynamic alterations occurring during cardiac surgery. It is particularly indicated in patients with preoperative NYHA class III or IV congestive heart failure.