Kleinere Studien haben erstmals die arteriovenöse CO2-Differenz als neuen Parameter einer Gewebehypoxie untersucht. Basis hierfür ist die Hypothese, dass ein erhöhter arterieller CO2-Partialdruck infolge einer Minderperfusion eine unzureichende Gewebeoxygenierung darstellt. Die arteriovenöse CO2-Differenz steigt somit bei abfallendem HZV an (inverse Korrelation zum HZV), das CO2 im insuffizient durchbluteten Gewebe kann nicht mehr extrahiert werden.

Kiss, G.; Joulin, O.; Habchi, S.; Akkad, R.; Desbordes, J.; Robin, E. Author Information

La perspective d’une utilisation mieux validée des techniques non invasives d’analyse de l’onde de pouls pourrait offrir de multiples apports en pratique clinique. Dans ce domaine, le monitorage non invasif de la pression artérielle (PA) pourrait permettre un meilleur dépistage des variations tensionnelles rapides dans des situations d’instabilité hémodynamique où une mesure invasive est délicate ou peu habituelle à mettre en oeuvre. Le caractère continu de la mesure est également intéressant pour l’évaluation immédiate de l’efficacité d’une épreuve de remplissage. Par ailleurs, et quoique la validation reste à établir en pratique clinique, la généralisation d’une mesure non invasive continue de la variation respiratoire de la pression pulsée semble prometteuse chez les patients recevant une anesthésie générale ou une sédation en ventilation contrôlée, pour guider le remplissage vasculaire en peropératoire (chirurgie viscérale moyenne avec pertes insensibles, orthopédique, orthognatique…), mais également dans le cadre de l’optimisation hémodynamique en préhospitalier, aux urgences ou à l’entrée en réanimation. Pour les patients de réanimation, la mise en place d’un cathéter artériel radial reste la référence lorsque le contexte clinique (choc, utilisation de catécholamines) rend l’utilisation d’une mesure non invasive difficile et ininterprétable.

BACKGROUND:This study aimed to evaluate the implementation of a strategy to prevent postoperative nausea and vomiting (PONV) in patients undergoing general surgery.STUDY DESIGN:Prospective observational study.METHODS:A first period was observational. During a second period, a strategy to prevent PONV was based on five risk factors (RF) identified after the first phase. From two RF, antiemetic treatment was given according to the number of RF. The incidence of PONV was recorded in postoperative anaesthesic care unit (PACU) and at the 24th postoperative hour (24h).RESULTS:We prospectively enrolled 823 patients. Implementation of a prophylactic PONV strategy was associated with a decrease of nausea in PACU from 29.9 to 9.8% (P<0.001) and at 24h from 19 to 10.3% (P<0.001). Vomiting decreased from 12.4 to 2.3% (P<0.001) in PACU and from 5.6 to 3.7% at 24h (non-significant).CONCLUSION:Prophylaxis of PONV by the administration of antiemetic treatment according to a strategy based on a local risk score was efficient and associated with a significant decrease of PONV.

Secq, E.; Robin, E.; Habchi, S.; Desanlis, E.; Decoene, C.; Vallet, B. Author Information

Department of Anaesthesiology and Intensive Care, Huriez Hospital, Lille Teaching Hospital, Lille Cedex, France, Metropolitan

OBJECTIVE:The purpose of this review is to draw up a statement on current knowledge available on the more recent hydroxyethyl starch (HES). DATA SOURCES:References were obtained from computerized bibliographic research (Medline), recent review articles, the library of the service and personal files. STUDY SELECTION:All categories of articles on this topic have been selected. DATA EXTRACTION:Articles have been analysed for biophysics, pharmacology, toxicity, side effects, clinical effects and using prospect of HES. DATA SYNTHESIS:The first HES was made available in the United States in 1970. The development of a new generation of HES restarted the discussion on clinical interest and the limits in the use of these macromolecules. This interest is also strengthened today by the recent data attached to plasma substitution in intensive care or perioperative resuscitation. The interest for crystalloids and colloids is still widely debated, and among the latter, the relative interest of the HES last generation compared to older ones. Recent HES development is in line with a decrease molecular weight, change rate molar substitution and to amend the glucose to hydroxyethyl report. The ultimate goal is to reduce the side effects of these molecules preventing their use. Side effects are dominated by haemostasis and renal dysfunction. The latest developments are the so-called HES "balanced" solutions.

Objectives. - To assess the difficulty in both laryngoscopy and tracheal intubation related to goitre and to identify factors predictive of difficult intubation due to this condition. Study design. - Prospective observational.Methods. - We used the Intubation Difficulty Scale (IDS) in 80 consecutive patients with large goitre (defined by the inability to palpate the cricoid cartilage, the presence of endothoracic goitre, tracheal deviation of more than 1 cm or tracheal stenosis on the chest x-ray) and 77 control patients.Results. - Cormack grades 3-4 were more frequent at initial laryngoscopy in patients with goitre (23/80 vs. 9/77; p < 0.05), but the difference was no longer significant after application of an external laryngeal pressure (8/80 vs. 5/77). IDS scores (median [25th-75th percentiles]) were higher in the goitre group (1 [0 - 4]) than in the control group (0[0 - 1]; p = 0.001), corresponding to an increase in slightly difficult intubation (IDS 1-5: 36/80 vs. 15/77; p < 0.05). However, incidence of moderate to major difficulty in intubation (IDS > 5: 8/80 vs. 7/77) as well as time to completion of intubation were similar in both groups. Tracheal stenosis (>= 30%) and reduced mouth opening (< 4.4 cm) were the only significant predictors of increased difficulty in intubation in patients with a goitre.Conclusion. - Large goitres are usually associated with slight difficulty in intubation only. Increased difficulty should be expected when severe tracheal stenosis is present on chest x-ray, especially when associated with a reduced mouth opening. (C) 2010 Elsevier Masson SAS. All rights reserved.

Departments of Anesthesiology and Intensive Care and Thoracic Surgery, University Hospital of Lille, Lille, France

To analyze the current knowledge related to xenon anaesthesia.References were obtained from computerized bibliographic research (Medline), recent review articles, the library of the service and personal files.All categories of articles on this topic have been selected.Articles have been analyzed for biophysics, pharmacology, toxicity and environmental effects, clinical effects and using prospect.The noble gas xenon has anaesthetic properties that have been recognized 50 years ago. Xenon is receiving renewed interest because it has many characteristics of an ideal anaesthetic. In addition to its lack of effects on cardiovascular system, xenon has a low solubility enabling faster induction of and emergence from anaesthesia than with other inhalational agents. Nevertheless, at present, the cost and rarity of xenon limits widespread use in clinical practice. The development of closed rebreathing system that allowed recycling of xenon and therefore reducing its waste has led to a recent interest in this gas.Reducing its cost will help xenon to find its place among anaesthetic agents and extend its use to severe patients with specific pathologies.

Objective. - To analyze the current knowledge related to xenon anaesthesia.Data sources. - References were obtained from computerized bibliographic research (Medline (R)), recent review articles, the library of the service and personal files.Study selection. - All categories of articles on this topic have been selected.Data extraction. - Articles have been analyzed for biophysics, pharmacology, toxicity and environmental effects, clinical effects and using prospect.Data synthesis. - The noble gas xenon has anaesthetic properties that have been recognized 50 years ago. Xenon is receiving renewed interest because it has many characteristics of an ideal anaesthetic. In addition to its lack of effects on cardiovascular system, xenon has a low solubility enabling faster induction of and emergence from anaesthesia than with other inhalational agents. Nevertheless, at present, the cost and rarity of xenon limits widespread use in clinical practice. The development of closed rebreathing system that allowed recycling of xenon and therefore reducing its waste has led to a recent interest in this gas.Conclusion. - Reducing its cost will help xenon to find its place among anaesthetic agents and extend its use to severe patients with specific pathologies. (C) 2010 Published by Elsevier Masson SAS.

Data synthesis The first HES was made available in the United States in 1970. The development of a new generation of HES restarted the discussion on clinical interest and the limits in the use of these macromolecules. This interest is also strengthened today by the recent data attached to plasma substitution in intensive care or perioperative resuscitation. The interest for crystalloids and colloids is still widely debated, and among the latter, the relative interest of the HES last generation compared to older ones. Recent HES development is in line with a decrease molecular weight, change rate molar substitution and to amend the glucose to hydroxyethyl report. The ultimate goal is to reduce the side effects of these molecules preventing their use. Side effects are dominated by haemostasis and renal dysfunction. The latest developments are the so-called HES “balanced” solutions.

BACKGROUND:This study aimed to evaluate whether exposure to sevoflurane at the onset of reperfusion provides protection similar to sevoflurane preconditioning and whether the effect depends on mitochondrial potassium ATP-dependent channel (mitoK(ATP)) in a rat model of focal cerebral ischaemia.METHODS:Adult Wistar male rats were subjected to focal cerebral ischaemia for 1 h followed by 24 h or 7 days of reperfusion. Preconditioning consisted of 15 min exposure to sevoflurane at 1 minimum alveolar concentration (2.6%) 72 h before ischaemia. Post-conditioning was performed by exposure to sevoflurane immediately at the onset of reperfusion or by a delayed exposure 5 min after the onset of reperfusion. The role of the mitoK(ATP) channel was assessed by i.p. injection of the selective blocker 5-hydroxydecanoate before each sevoflurane administration or by the mitoK(ATP) channel opener, diazoxide (DZX), given in place of sevoflurane. Cerebral infarct size, neurological deficit score, and motor coordination were evaluated 24 h and 7 days after reperfusion.RESULTS:Sevoflurane preconditioning and early post-conditioning reduced both cerebral infarct size and neurological defect score at 24 h of reperfusion whereas the sole sevoflurane post-conditioning improved motor coordination. At 7 days, only infarct volume remained lower in pre- and post-conditioned animals. Neuroprotection mediated by sevoflurane was lost when it was given 5 min after the onset of reperfusion and was abolished by inhibition of mitoK(ATP). DZX alone mimicked sevoflurane-induced pre- and post-conditioning.CONCLUSIONS:The pretreatment with sevoflurane or its early administration at reperfusion provides neuroprotection via mitoK(ATP) in a rat model of focal cerebral ischaemia.

Central venous oxygen saturation (ScvO2) has been shown to be a useful therapeutic target in septic shock or high-risk surgery. The central venous-to-arterial carbon dioxide difference (Pcv-aCO2) has been proposed as a complementary tool for goal-directed therapy (GDT) in septic shock. We tested the hypothesis that both ScvO2 and Pcv-aCO2 could be used as complementary tools for GDT during high-risk surgery.

This article is one of ten reviews selected from the Yearbook of Intensive Care and Emergency Medicine 2010 (Springer Verlag) and co-published as a series in Critical Care. Other articles in the series can be found online at http://ccforum.com/series/yearbook. Further information about the Yearbook of Intensive Care and Emergency Medicine is available from http://www.springer.com/series/2855.

Adequate volume expansion (VE) in patients with evidence of hypoperfusion should be aimed not only at achieving an increase in stroke volume (SV) and cardiac index (CI) but also at improved tissue perfusion and oxygenation. Our aim in this study was to assess the dynamic changes in muscle tissue oxygen saturation (StO2) during hypovolaemia and in response to VE.

BACKGROUND Off-line calculation of the pulse pressure variation (PPV(ref)) has repeatedly been shown to be a reliable predictor of fluid responsiveness in mechanically ventilated patients. This study was designed to assess the ability of two algorithms for automated calculation of PPV (PPV(auto)) (Intellivue MP 70) and stroke volume variation (SVV(auto)) (FloTrac/Vigileo) to predict fluid responsiveness during abdominal surgery. METHODS We conducted a prospective study of 56 fluid challenges given for haemodynamic instability in 11 patients undergoing major abdominal surgery. Fluid responsiveness was defined as an increase in stroke volume index (SVI) >10%. PPV(ref), PPV(auto), SVV(auto), and SVI (oesophageal Doppler) were recorded simultaneously before and after each fluid challenge. RESULTS PPV(auto) and SVV(auto) both correlated with PPV(ref) [r(corr)=0.87 (P<0.0001) and 0.84 (P<0.0001), respectively; n=77]. All three indices measured before fluid challenges were higher in responder (n=32) than in non-responder (n=24) fluid challenges (P < or = 0.02). The mean areas under the receiver operating characteristic curves were 0.96 (PPV(ref)), 0.96 (PPV(auto)), and 0.95 (SVV(auto)), and the optimal threshold value for each variable was 13%, 13%, and 12%, respectively. All indices correlated with the fluid challenge-induced changes in SVI (PPV(ref): r(corr)=0.65; PPV(auto): r(corr)=0.58; SVV(auto): r(corr)=0.58, P<0.001 for all). CONCLUSIONS PPV(auto) and SVV(auto) predict fluid responsiveness as accurately as off-line PPV(ref) in patients with haemodynamic instability during major abdominal surgery.