Reducing tidal volume and increasing positive end-expiratory pressure with constant plateau pressure during one-lung ventilation: effect on oxygenation.

BACKGROUND: It is no longer safe to use large tidal volumes (V(T)) (>8 ml kg(-1)) for one-lung ventilation (OLV), and limiting plateau pressure should be a major objective. Due to the specificity of OLV, the use of positive end-expiratory pressure (PEEP) remains controversial. This study determined whether at the same low plateau pressure, reducing V(T) and increasing PEEP were not inferior to larger V(T) and lower PEEP ventilation in terms of oxygenation. METHODS: This prospective, randomized, non-inferiority, cross-over trial included 88 patients undergoing open thoracotomy who received two successive ventilatory strategies in random order: V(T) (8 ml kg(-1) of ideal body weight) with low PEEP (5 cm H(2)O), or low V(T) (5 ml kg(-1)) with a high PEEP. Respiratory rate and PEEP were, respectively, adjusted to maintain constant ventilation and plateau pressure. The primary endpoint was the ratio under each ventilatory strategy. RESULTS: The non-inferiority of low-V(T) ventilation could not be established. The mean adjusted ratio was lower overall during low-V(T) ventilation, and differences between the two ventilatory modes varied significantly according to baseline (T0). Decreased oxygenation during low V(T) was smaller when baseline values were low. Systolic arterial pressure was not lower during low-V(T) ventilation. CONCLUSION: During OLV, lowering V(T) and increasing PEEP, with the same low plateau pressure, reduced oxygenation compared with larger V(T) and lower PEEP. This strategy may reduce the risk of lung injury, but needs to be investigated further.

Pressure-controlled ventilation and intrabronchial pressure during one-lung ventilation.

BACKGROUND: Pressure-controlled ventilation (PCV) has been suggested to reduce peak airway pressure (P(peak)) and intrapulmonary shunt during one-lung ventilation (OLV) when compared with volume-controlled ventilation (VCV). At the same tidal volume (V(T)), the apparent difference in P(peak) is mainly related to the presence of a double-lumen tracheal tube. We tested the hypothesis that the decrease in P(peak) observed in the breathing circuit is not necessarily associated with a decrease in the bronchus of the dependent lung. METHODS: This observational study included 15 consecutive subjects who were ventilated with VCV followed by PCV at constant V(T). Airway pressure was measured simultaneously in the breathing circuit and main bronchus of the dependent lung after 20 min of ventilation. RESULTS: PCV induced a significant decrease in P(peak) [mean (sd)] measured in the breathing circuit [36 (4) to 26 (3) cm H(2)0, P<0.0001] and in the bronchus [23 (4) to 22 (3) cm H(2)O, P=0.01]. However, the interaction (ventilatory mode x site of measurement) revealed that the decrease in P(peak) was significantly higher in the circuit (P<0.0001). Although the mean percentage decrease in P(peak) was significant at both sites, the decrease was significantly lower in the bronchus [5 (6)% vs 29 (3)%, P<0.0001]. CONCLUSIONS: During PCV for OLV, the decrease in P(peak) is observed mainly in the respiratory circuit and is probably not clinically relevant in the bronchus of the dependent lung. This challenges the common clinical perception that PCV offers an advantage over VCV during OLV by reducing bronchial P(peak).

Safety of HES 130/0.4 (Voluven(R)) in patients with preoperative renal dysfunction undergoing abdominal aortic surgery: a prospective, randomized, controlled, parallel-group multicentre trial.

BACKGROUND AND OBJECTIVE: Patients with impaired renal function are at risk of developing renal dysfunction after abdominal aortic surgery. This study investigated the safety profile of a recent medium-molecular-weight hydroxyethyl starch (HES) preparation with a low molar substitution (HES 130/0.4) in this sensitive patient group. METHODS: Sixty-five patients were randomly allocated to receive either 6% hydroxyethyl starch (Voluven); n = 32) or 3% gelatin (Plasmion); n = 33) for perioperative volume substitution. At baseline, renal function was impaired in all study patients as indicated by a measured creatinine clearance < 80 mL min(-1). The main renal safety parameter was the peak increase in serum creatinine up to day 6 after surgery. RESULTS: Both treatment groups were compared for non-inferiority (pre-defined non-inferiority range hydroxyethyl starch < gelatin + 17.68 micromol L(-1) or 0.2 mg dL(-1). Other renal safety parameters included minimum postoperative creatinine clearance, incidence of oliguria and adverse events of the renal system. Baseline characteristics, surgical procedures and the mean total infusion volume were comparable. Non-inferiority of hydroxyethyl starch vs. gelatin could be shown by means of the appropriate non-parametric one-sided 95% CI for the difference hydroxyethyl starch-gelatin [-infinity, 11 micromol L(-1)]. Oliguria was encountered in three patients of the hydroxyethyl starch and four of the gelatin treatment group. One patient receiving gelatin required dialysis secondary to surgical complications. Two patients of each treatment group died. CONCLUSION: As we found no drug-related adverse effects of hydroxyethyl starch on renal function, we conclude that the choice of the colloid had no impact on renal safety parameters and outcome in patients with decreased renal function undergoing elective abdominal aortic surgery.

[High-volume hemofiltrations].

Almost 10 years ago, standard hemofiltration (HF) was carried out at an ultrafiltration (UF) rate of not more than 2 1/hour and only a predilution variant was usually used. However, after Ronco published the results of his study early in the 20th century the situation changed as this study provided evidence that increasing an UF rate up to 35 ml/kg/hr had a positive effect in patients with acute renal failure (ARF). At the same time, there was a new standard for the determination of high-volume HF (HVHF) and new concepts generalized in this paper have emerged. Moreover, two different procedures of HVHF: (1) a continuous high-volume technique providing a rate of 50-70 ml/kg/hr during 24 hours; (2) an intermittent high-volume technique, the so-called HVHF with short courses of treatment, a very high volume at a rate of 100-120 ml/kg/hr during 4-8 hours. Later on this technique came to be called pulse HVHF. Both methods are designated by the abbreviation HVHF, but their concepts and results are slightly different, as will be discussed below. As for the higher doses of plasma replacement therapy, it is necessary to put the results of two recently published studies into routine clinical practice of continuous vein-venous HF (CVVHF) as soon as possible just in 2008. The performed studies suggest the most important role of adequate dosage of CVVHF and show that the use of a dose of 35 ml/kg/hr in critically ill patients with ARF increased survival by almost 20%. These two studies contain today's most vivid evidence, but one awaits the results of other studies that confirm (or do not confirm) these conclusions. In the world where more importance is attached to evidence-based medicine, two first-level studies will yield Stage A recommendations that may be guided by any intensive care specialist using CVVHF in expectation of the results of on-going investigations. Nevertheless, many difficulties are to be surmounted while introducing new procedures into routine intensive care practice. The most cardinal problems are those associated with requirements for blood flow via vascular access with pre- and postdilution procedures, with the type of employed membranes and substituting liquids, and with a possible need for concomitant dialysis. From the strictly practical standpoint, introduction of these changes into routine intensive care practice may be extremely difficult. This will undoubtedly require that physicians and nurses should make joint effects.

The big bang of hemofiltration: the beginning of a new era in the third millennium for extra-corporeal blood purification!

Since the last decade, hemofiltration and especially high volume hemofiltration has rapidly evolved from a somewhat experimental treatment towards a potentially effective 'adjunctive' therapy in severe septic shock and especially refractory or catecholamine resistant hypodynamic septic shock. Nevertheless, this approach lacks prospective randomized studies (PRT'S) evaluating the critical role of early hemofiltration in sepsis. An important step forward which could be called the 'big bang' in term of hemofiltration was the publication of a PRT in patients with acute renal failure (ARF) (1). Before this study (2), nobody believed that hemofiltration could change the survival rate in intensive care. Since that big bang, many physicians consider that hemofiltration at a certain dose can change the survival rate in intensive care. So the world of hemofiltration in ICU is not a definitive world, it is still in expansion. Indeed, we now have to try to define what will be the exact dose we need in septic acute renal failure. This dose might well be 'higher' than 35 ml/kg/hour in the septic acute renal failure 'group' as suggested by many studies (2-5). At present, it is the issue of continuous dose of high volume hemofiltration that has to be tested in future randomized studies. Since the Vicenza study (2) has shown that 35 ml/kg/h is the best dose in terms of survival, dealing with non septic acute renal failure in ICU, several studies from different groups have shown that, in septic acute renal failure, a higher dose might correlate with better survival. This has also been shown in some way by the study of the 'Vicenza group' but not with a statistically significant value (2). New PRT'S have just started in Europe like the IVOIRE study (hIgh VOlume in Intensive caRE) (6) and the RENAL study. Another large study is looking more basically at dose in non septic acute renal failure in Australasia and is led by the group of Rinaldo Bellomo in Melbourne (7) as well as the ATN study (8) led by Palevsky and colleagues in the USA, also testing the importance of dose in the treatment for ARF. Nevertheless, 'early goal-directed hemofiltration therapy' like early goal directed therapy (9) has to be studied in our critical ill patients. Regarding this issue, fewer studies, mainly retrospective exist, but again the IVOIRE study (6) will address this issue by studying septic patients with acute renal injury according to the Rifle classification (10). So, this review focuses on the early application and on the adequate dose of continuous high volume hemofiltration in septic shock in order to improve not only hemodynamics, but survival in this very severely ill cohort of patients. This could well be called the 'big bang of hemofiltration' as one could never have anticipated that an adequate dose of hemofiltration could markedly influence the survival rate of ICU-septic acute renal failure patients. On top of the use of early and adequate dose of hemofiltration in sepsis, a higher dose could also provide better renal recovery rate and reduce the risk of associate chronic dialysis in these patients. Furthermore, this paper also reviews 'brand' new theories regarding the rationale for hemofiltration in sepsis. Finally, this paper also addresses the so-called negative studies as well anticipated side effects.

[Perioperative anticoagulation management for prosthetic heart valves]. / Gestion en période périopératoire de l'anticoagulation des valves prothétiques cardiaques.

OBJECTIVES: The practices and the guidelines over the perioperative management of the anticoagulation of patients with cardiac valves prothesis are the object of no consensual attitude. The thrombotic risk over the time is well known. It depends of the type or the location on the valve, of their associations and the age of the patient. In the perioperative period, the antithrombotic treatment must be interrupted according to the surgical haemorrhagic risk. STUDY DESIGN: Short review. RESULTS: Only patients, without associated risk factor, carriers of bioprosthesis from more than 3 months, can be maintained only under antiplatelets agents. In others situations, the caution imposes a bridge of anticoagulants from 48 to 72 hours with unfractionated heparin (subcutaneous at home, intravenous at the hospital). Low molecular weight heparin has no commercial authorization in this indication. The resumption of the anticoagulation by unfractionated heparin in postoperative period must be the most premature possible after the decrease of the surgical bleeding. The relay by vitamin K antagonists has to be made over 48 to 72 hours. Within the framework of the urgency, the surgical haemorrhagic risk is weak for an INR <1.5. According to the urgency of the surgery, a treatment by vitamin K (if the delay is over 12 hours) or by prothrombinic complex allows to correct this INR. The identification of thrombotic complications requires a particular attention. In the postoperative period, as soon as there is suspicion of thrombosis, clinical manifestations must be consolidated by the practice of a transoesophageal echography, which only confirm the diagnosis.

A long-term follow-up of an HIV type 1-infected patient reveals a coincidence of Nef-directed cytotoxic T lymphocyte effectors and high incidence of epitope-deleted variants.

Cytotoxic T lymphocytes (CTL) play a critical role in controlling human immunodeficiency virus-1 (HIV-1) and simian immunodeficiency virus (SIV) infections. However, in spite of developing a strong CTL response most HIV-1-infected patients eventually progress to AIDS. Amino acid changes in CTL epitope have been previously described and may permit HIV to escape from CTL immune responses. The importance of CTL selection pressure in controlling the course of viral evolution in HIV-infected patient remains debatable. For over a 10-year period, we longitudinally followed a patient for bulk unstimulated effector (eCTL) and stimulated memory CTL responses (mCTL) against the viral proteins Gag, Pol, and Nef. The patient showed a strong CTL response against Nef in unstimulated peripheral blood mononuclear cells with a peak during Month 40 of the follow-up. The mCTL response was also higher against Nef than Gag and Pol. PCR amplification and nucleotide sequencing of the plasma viral variants showed a viral variant with the epitope deletion that was detected early during the follow-up and essentially replaced the wild-type virus during the peak eCTL response. These studies support the importance of Nef epitope deletion as a mechanism for HIV-1 escape from CTL immune pressure.

In vitro accuracy of three blood O2 saturation optic catheter systems.

OBJECTIVE: The measure of the precision and accuracy of three optic SvO2 systems in vitro (SAT-2 Baxter, oximetrix 3 Abbott, HEMOPRO-2 Spectramed in a wide range of saturations (24-85%) and hematocrit (20-40%). DESIGN: In vitro comparison of the results given by a Co-Oximeter and the SvO2 systems. MEASUREMENTS AND RESULTS: 144 blood samples were tonometered with a variety of gas mixtures. Measurements of SvO2 were compared to those obtained by means of a Co-Oximeter, the difference (dSO2) between paired values were calculated. Precision was evaluated from confidence intervals (2SD) and accuracy was tested using dSO2 figures. As there was no difference in either precision or accuracy among catheters for a given system, data obtained from a given system were pooled. Mean precision was 14.2%, 8.6%, 9% for the Spectramed, Baxter and Abbott systems, respectively. CONCLUSION: The rather low reliability of the optic method should be borne in mind in patients with low SvO2 and/or low hematocrit.

Reduction in requirements for allogeneic blood products: nonpharmacologic methods.

BACKGROUND: Various strategies have been proposed to decrease bleeding and allogeneic transfusion requirements during and after cardiac operations. This article attempts to document the usefulness, or lack thereof, of the nonpharmacologic methods available in clinical practice. METHODS: Blood conservation methods were reviewed in chronologic order, as they become available to patients during the perisurgical period. The literature in support of or against each strategy was reexamined critically. RESULTS: Avoidance of preoperative anemia and adherence to published guidelines for the practice of transfusion are of paramount importance. Intraoperatively, tolerance of low hemoglobin concentrations and use of autologous blood (predonated or harvested before bypass) will reduce allogeneic transfusions. The usefulness of plateletpheresis and retransfusion of shed mediastinal fluid remains controversial. Intraoperatively and postoperatively, maintenance of normothermia contributes to improved hemostasis. CONCLUSIONS: Several approaches have been shown to be effective. An efficient combination of methods can reduce, and sometimes abolish, the need for allogeneic blood products after cardiac operations, inasmuch as all those involved in the care of cardiac surgical patients adhere thoughtfully to existing transfusion guidelines.

Extracorporeal circulation, hemocompatibility, and biomaterials.

BACKGROUND: Performance of a majority of cardiac surgical procedures requires the use of extracorporeal circulation. Contact of the patients' blood with the nonendothelial surface of the cardiopulmonary bypass circuit is responsible for several, potentially harmful systemic reactions. METHODS: The patients' response to extracorporeal circulation is reviewed briefly. The interactions between patient and circuit are discussed not only as they relate to blood-material contact, but also from a mechanical and rheologic standpoint. The theoretic benefits of the newer, more hemocompatible materials are presented, along with a review of published clinical experience with heparinized cardiopulmonary bypass circuits. RESULTS: The response to extracorporeal circulation extends far beyond a simple derangement of hemostasis. This inflammatory response is strongly influenced by the rheologic design of the circuit and by the physical and chemical properties of the surface. Heparinized circuits decrease inflammation, but the clinical benefits of this reduction remain unclear, except for extended cardiopulmonary support. The safe use of these circuits requires full heparinization and does not reduce allogeneic transfusions. CONCLUSIONS: Clinicians are still in the search of the ideal material and the ideal extracorporeal circuit design. Newer, heparinized materials offer real but limited clinical benefits.

Inhibition of platelet aggregation by abciximab but not by aspirin can be detected by a new point-of-care test, the hemostatus.

We have investigated the type of platelet defect that can be detected with the Hemostatus test performed with the Hepcon/HMS instrument (Medtronic) designed to investigate platelet function during and after surgery. This assay is based on the comparison of the activated clotting time of whole blood measured in cartridges containing kaolin or kaolin and platelet-activating factor in different concentrations. Addition of platelet-activating factor shortened the blood activated clotting time when the platelet counts were normal. However, when platelet counts were below 70000/microL, the activated clotting time was prolonged in all channels including those without platelet-activating factor showing the influence of platelets in the formation of the clot under the conditions tested. Inhibition of platelet aggregation with c7E3 (abciximab, ReoPro) also induced a much-prolonged activated clotting time, and a similar finding was seen with blood from a patient with Glanzmann's thrombasthenia confirming the need for platelet aggregation and/or the glycoprotein (GP) IIb-IIIa complex. In contrast, the interaction of GP Ib with von Willebrand Factor was not of major importance, since inhibition of this interaction with the anti-GP Ib murine monoclonal antibody, ALMA-12, did not modify the activated clotting time. Furthermore, the activated clotting time measured for patients with an acquired defect in von Willebrand Factor activity were unchanged. Finally, inhibition of thromboxane A2 formation by aspirin did not influence the results of this test. Globally, the Hemostatus test was able to detect major abnormalities of GP IIb-IIIa function in the presence or absence of platelet-activating factor.

Electronic ventilator temperature sensors as a potential source of respiratory tract colonization with Stenotrophomonas maltophilia.

Stenotrophomonas maltophilia (S. maltophilia) is an important cause of nosocomial infection among ventilated and immunocompromised patients, and among patients receiving broad-spectrum antimicrobials. We report a cluster of patients in a surgical intensive care unit who were colonized or infected with S. maltophilia. An epidemiological investigation was initiated after surveillance data revealed that eight patients were culture-positive from sputum for S. maltophilia in the preceding month. Review of respiratory care procedures revealed that when mechanical ventilators were serviced between patients, the electronic temperature probes used with servo-controlled humidifiers were wiped with inadequate disinfection. We collected cultures of case-patient room surfaces, sinks and ventilator equipment. S. maltophilia was recovered from room surfaces, ventilator expiratory circuits and a temperature sensor which had been kept in ambient air after disinfection. Patients and environmental isolates were examined by RAPD-PCR. Three clinical isolates and one environmental isolate had the same profile, which suggests cross-contamination or common source exposure. The outbreak was controlled by adequate disinfection of the temperature sensors. No single epidemic strain was identified but several observations support the conclusion that the temperature probes contributed to the outbreak.

Changes in type B natriuretic peptide (BNP) concentrations during cardiac valve replacement.

OBJECTIVE: The aim of our study was to investigate the ability of BNP levels to reveal the immediate post-surgery cardiac function improvement. We measured the perioperative variations in BNP concentrations in patients scheduled for cardiac surgery with cardiopulmonary bypass (CPB), chronic mitral regurgitation, valvular aortic stenosis, or myocardial ischaemia. METHODS: Three groups were included: patients with coronary artery bypass graft (CABG, group I, n = 14), aortic (AVR, group II, n = 14) or mitral (MVR, group III, n = 7) valve replacement. BNP assay was performed at the induction of anesthesia, immediately after the CPB, at the arrival in the intensive care unit, 4 h, 8 h and 12 h after the arrival in ICU. RESULTS AND CONCLUSION: The occurring variation in BNP levels after the operation is an increase whatever the corrective surgery, underlying the relative lack of specificity of BNP with regard to the cardiac pathology. Besides iatrogenic cardioplegia one can supposes that cardiac surgery involves other major stimuli such as anesthesia, sternotomia, hemodynamics, post-operative that could influence in a non specific way BNP levels.

Late reoperations after aorto-iliac restaurations.

(1) Late thrombosis after aorto-iliac revascularisations are infrequent when the operation is correctly performed and controlled by intra-operative angiography. (2) Reoperation after thromboendarterectomy is a difficult procedure requiring great care in the aortic approach. (3) Reoperation after thrombosis of a prosthetic graft is much easier as far as dissection is concerned, usually the upper part of the former prosthesis may be kept, which renders the procedure very much easier. (4) The distal anastomosis should be realised distally to the sclerotic block surrounding the femoral bifurcation. (5) In case of poor risk patients, it is better to use extra-anatomical bypasses, and if necessary, one must be able to sacrifice a limb for a life. Mortality rates are high in our series. It may be due in part to a too much optimistic pre-operative evaluation and selection of our patients, in the first years of our experience.

Rationale for the design of biomaterials and the evaluation of their biocompatibility.

The biocompatibility of a material can be considered as the ideally expectable result of its interactions with living tissues with which it is interfaced. This property determines the ability of devices involving this material in their constitution, to correctly assume their ascribed function; reciprocally a bad fitting, between devices and their intended use, coming from a non-optimized design or from an inappropriate prescription, may alter the original biocompatibility of constitutive materials. Accordingly, the actual biocompatibility of a biomaterial depends upon both its intrinsic properties and the application in which it is involved. Such considerations must be taken into account by specialists who try to design more performant biomaterials, or new assist devices, should they be implantable or not; but they draw also methodological guidelines for the evaluation of the biocompatibility of these biomedical products.

[Conditions of practice of upper digestive endoscopy in ambulatory care. Results of a national survey (I)]. / Conditions de réalisation de l'endoscopie digestive haute en ambulatoire. Résultats d'une enquête nationale (I).

OBJECTIVES: The aim of the study was to describe the usual conditions of practice of esophagogastroscopy in ambulatory care by French gastroenterologists. METHODS: During a week, a questionnaire was filled out for each esophagogastroscopy performed in ambulatory or day care. RESULTS: Seven hundred and thirty nine gastroenterologists participated in the study (25.9% of French gastroenterologists) and enrolled 4585 patients. Intra-venous sedation was performed in 36.6% of endoscopic examinations, with diazepam (17.8%), midazolam (41.7%), propofol (14.9%), diazepam and propofol (2.1%) or midazolam and propofol (23.5%). A morphinomimetic was associated in 58.6% of cases. Monitoring equipment of endoscopy units was: aspiration (58.6%), pulse oxymeter (41.6%), electrocardiographic monitoring (37.7%). Recommendations about follow-up after ambulatory anaesthesia were not implemented in 7.3% of examinations with anaesthesia (patient discharged alone). Seventeen minor adverse events were recorded. CONCLUSION: The study underlines variability of practice, mainly about use of sedation, monitoring and follow-up of patients during esophagogastroscopy performed in ambulatory care in France. An improvement in quality of endoscopy practice is likely.

[Patient's opinion following an upper digestive endoscopy in ambulatory care. Results of a national survey (II)]. / Opinion des patients après la réalisation d'une endoscopie digestive haute en ambulatoire. Résultats d'une enquête nationale (II).

OBJECTIVES: The aim of the study was to evaluate patient satisfaction after esophagogastroscopy performed in ambulatory care and to correlate it with conditions of usual practice. METHODS: Study was proposed to the French gastroenterologists. During a week, 2 questionnaires were filled out for each esophagogastroscopy performed in ambulatory care: one recorded conditions of examination and one was independently filled out by the patient one day after endoscopy. RESULTS: Seven hundred and thirty nine gastroenterologists and 4,585 patients participated in the study. Among the patients, 3,758 (82%) filled out the questionnaire. Sedation was performed in 36.6% of cases. Subsequent endoscopy would be accepted by 79.3% of patients in the same conditions. Acceptance was significantly better with use of sedation and use of propofol. Without sedation, independent factors associated with a better acceptance were: male gender, absence of habitual benzodiazepine medication, endoscopy performed in private practice or private hospitals, smaller size of endoscope. CONCLUSION: This study underlines factors associated with a good acceptance of esophagogastroscopy without sedation and could help to improve decision-making regarding use of sedation.

[Quality of psychomotor recovery after colonoscopy under general anesthesia using propofol. Value of tests of awakening]. / Qualité de la récupération psychomotrice après une coloscopie sous anesthésie générale par propofol. Intérêt des tests de réveil.

Achieving colonoscopy under general anaesthesia entails the problem of ambulatory-care anaesthesia, in particular because perception of patient's recovery determines to some extent the length of monitoring following colonoscopy. The aims of the study was to assess the quality of patient's recovery after a colonoscopy under general anaesthesia while using propofol, by means of psychomotor-tests. METHODS--Colonoscopy was performed in 40 patients according to the following anaesthetic protocol: induction: propofol 2 mg/kg, continuous support: propofol 10 mg/kg/h i.v. with a 50 mg bolus in case of insufficient sedation; series of 3 psychomotor-tests were performed the day before and 1 hour, 3 hours and 6 hours after colonoscopy. The 3 psychomotor-tests studied: coordination (Newman test), time-space orientation and short-term memory. RESULTS--Forty patients, 25 females and 15 males, underwent colonoscopy with general anaesthesia for an average time-period of 22 +/- 11 min. The mean dose of propofol used was 286 +/- 102 mg. Awakening was complete in all patients, according to physical criteria such as consciousness and cardiovascular status, 20 min after receiving colonoscopy. The average psychomotor-tests results over time were (as percentages of original values) (*P < 10(-3); **P < 0.05): [table: see text] At 6 hours, 35 patients (87.5%) had recovered to their original performance and at 3 hours, 30 patients (75%) retained 90% their former state as measured with 3 psychomotor-tests. Neither by age or sex nor by propofol doses used or length or anaesthesia, the study population differed significantly. CONCLUSION--Three hours after colonoscopy under general anaesthesia using propofol, 30 patients (75%) had recovered at least 90% to their initial performances. Newman test was the most disturbed but there was no predictive factor for the quality of recovery. Psychomotor-tests may be useful before authorizing early discharge after colonoscopy under general anaesthesia but other recommendations about conditions of discharge after sedation must be also implemented.