Gérard Janvier

Hemovigilance network in France: organization and analysis of immediate transfusion incident reports from 1994 to 1998

BACKGROUND : Hemovigilance networks have been introduced in several countries to improve knowledge of blood transfusion‐related morbidity and mortality. The general organization of the French network and its results from 1994 through March 1999 are presented here.

Impact of High Volume Hemofiltration on Hemodynamic Disturbance and Outcome during Septic Shock

The purpose of this study was to evaluate the effect of high volume continuous venovenous hemofiltration (HVCVVH) on hemodynamic and outcome in patients with septic shock. The primary end point was mortality at 28 days. Study design was a prospective case series, and study setting was a 12 bed intensive care unit at a university hospital. A total of 24 consecutive patients with septic shock were included, with dysfunction of more than two organs. All patients were treated by HVCVVH with ultrafiltration rate between 40 ml · kg−1 · hr−1 and 60 ml · kg−1 · hr−1 for 96 hours. In all patients, the increase in hemodynamic parameters was statistically significant (p < 0.05), with a significant linear decrease in norepinephrine doses (p < 0.05). The predicted 28 day mortality by three different severity scores was more than 70%, and the mortality in the hemofiltration group was 46% (p < 0.075). In the present study of septic shock patients with organ dysfunction, the hemodynamic parameters increased regularly during treatment by HVCVVH. This study suggests a beneficial effect of HVCVVH on 28 day mortality (46%vs. 70%), and further studies with larger cohorts are required.

Validation of a continuous, arterial pressure-based cardiac output measurement: a multicenter, prospective clinical trial

IntroductionThe present study compared measurements of cardiac output by an arterial pressure-based cardiac output (APCO) analysis method with measurement by intermittent thermodilution cardiac output (ICO) via pulmonary artery catheter in a clinical setting.MethodsThe multicenter, prospective clinical investigation enrolled patients with a clinical indication for cardiac output monitoring requiring pulmonary artery and radial artery catheters at two hospitals in the United States, one hospital in France, and one hospital in Belgium. In 84 patients (69 surgical patients), the cardiac output was measured by analysis of the arterial pulse using APCO and was measured via pulmonary artery catheter by ICO; to establish a reference comparison, the cardiac output was measured by continuous cardiac output (CCO). Data were collected continuously by the APCO and CCO technologies, and at least every 4 hours by ICO. No clinical interventions were made as part of the study.ResultsFor APCO compared with ICO, the bias was 0.20 l/min, the precision was ± 1.28 l/min, and the limits of agreement were -2.36 l/m to 2.75 l/m. For CCO compared with ICO, the bias was 0.66 l/min, the precision was ± 1.05 l/min, and the limits of agreement were -1.43 l/m to 2.76 l/m. The ability of APCO and CCO to assess changes in cardiac output was compared with that of ICO. In 96% of comparisons, APCO tracked the change in cardiac output in the same direction as ICO. The magnitude of change was comparable 59% of the time. For CCO, 95% of comparisons were in the same direction, with 58% of those changes being of similar magnitude.ConclusionIn critically ill patients in the intensive care unit, continuous measurement of cardiac output using either APCO or CCO is comparable with ICO. Further study in more homogeneous populations may refine specific situations where APCO reliability is strongest.

Doppler resistive index to reflect regulation of renal vascular tone during sepsis and acute kidney injury

IntroductionRenal resistive index (RI), determined by Doppler ultrasonography, directly reveals and quantifies modifications in renal vascular resistance. The aim of this study was to evaluate if mean arterial pressure (MAP) is determinant of renal RI in septic, critically ill patients suffering or not from acute kidney injury (AKI).MethodsThis prospective observational study included 96 patients. AKI was defined according to RIFLE criteria and transient or persistent AKI according to renal recovery within 3 days.ResultsMedian renal RIs were 0.72 (0.68-0.75) in patients without AKI and 0.76 (0.72-0.80) in patients with AKI (P=0.001). RIs were 0.75 (0.72-0.79) in transient AKI and 0.77 (0.70-0.80) in persistent AKI (P=0.84). RI did not differ in patients given norepinephrine infusion and was not correlated with norepinephrine dose. RI was correlated with MAP (ρ= -0.47; P=0.002), PaO2/FiO2 ratio (ρ= -0.33; P=0.04) and age (ρ=0.35; P=0.015) only in patients without AKI.ConclusionsA poor correlation between renal RI and MAP, age, or PaO2/FiO2 ratio was found in septic and critically ill patients without AKI compared to patients with AKI. These findings suggest that determinants of RI are multiple. Renal circulatory response to sepsis estimated by Doppler ultrasonography cannot reliably be predicted simply from changes in systemic hemodynamics. As many factors influence its value, the interest in a single RI measurement at ICU admission to determine optimal MAP remains uncertain.

Target-controlled dosing of remifentanil during cardiac surgery reduces postoperative hyperalgesia.

OBJECTIVE One of the strategies to attenuate opioid-induced hyperalgesia (OIH) may be to decrease intraoperative doses of opioids by using target-controlled infusion (TCI). DESIGN Double-blind and randomized study. SETTING A single university hospital. PARTICIPANTS Forty American Society of Anesthesiologists II to III patients scheduled for elective cardiac surgery. INTERVENTIONS patients were randomized to 1 of the 2 groups: 1 group received an infusion of intraoperative remifentanil using TCI (target: 7 ng/mL), and the 2nd one was given an intraoperative continuous infusion (CI) (0.3 μg/kg/min). The anesthestic protocol and postoperative pain management were the same in both groups. The extent of mechanical dynamic hyperalgesia on the middle line perpendicular to the wound was considered the primary endpoint. The secondary endpoints were other results of dynamic and punctuate hyperalgesia until postoperative day 7, visual analog scale (VAS) and verbal rating scale (VRS) scores, and total morphine consumption until postoperative day 2. MEASUREMENTS AND MAIN RESULTS Morphometric and demographic characteristics and duration of surgery were comparable in both groups. Intraoperative remifentanil consumption was greater in CI than in TCI group (5,329 [1,833] v 3,662 [1,160] μg, p = 0.003). During the first 44 hours, there were no differences in morphine consumption, VAS, and VRS. The extent of hyperalgesia was significantly lower on postoperative days 1, 2, and 4 in the TCI group than in the CI group on the 3 evaluated lines (p < 0.05). Punctuate hyperalgesia evaluating 3 different points was lower in the TCI than in the CI group from postoperative day 1 until postoperative day 7 (p < 0.05). CONCLUSIONS The intraoperative decrease of opioid consumption when comparing the CI versus TCI mode of administration of remifentanil led to less OIH after cardiac surgery.

Propofol and sufentanil titration with the bispectral index to provide anesthesia for coronary artery surgery.

Background To provide anesthesia for cardiac surgery, hypnotics and opioids are frequently titrated on variables such as mean arterial pressure and heart rate. In this study conducted in patients scheduled to undergo coronary artery bypass grafting, propofol and sufentanil, both administered by computer-controlled infusion, were titrated on the Bispectral Index (BIS) values using a predefined algorithm. Methods After written informed consent, 110 patients, 95 men and 15 women aged 61 (9) yr [mean (SD)], were randomly allocated to receive predicted sufentanil effect site concentrations (Ce) of 0.5, 0.75, 1, 1.25, and 1.5 ng/ml, decreased by a third after sternotomy (groups 1–5). Target induction propofol concentration was 1.5 &mgr;g/ml and subsequently adjusted on BIS values. The following parameters were recorded: BIS values, predicted propofol Ce, the number of changes of propofol target, mean arterial pressure, heart rate, the number of bolus injection and doses of vasoconstrictor and vasodilator drugs, time to tracheal extubation, postoperative awareness and satisfaction scores, and cumulative morphine doses for the first postoperative day. Results One patient randomized to group 1 required 0.75 ng/ml sufentanil Ce instead of 0.5 ng/ml for increased BIS values on tracheal intubation. BIS values were similar in the five groups. The predicted propofol Ce values were different (P < 0.05; analysis of variance) among the five groups: 1.59 (0.47) to 1.23 (0.25) &mgr;g/ml in group 1 and group 4, respectively. Significantly fewer changes of propofol target were required in group 4 as compared to group 1. There were no differences among the five groups for mean arterial pressure, heart rate, time to tracheal extubation, awareness, satisfaction scores, and morphine requirements. Conclusion These results suggest the BIS, as part of an algorithm that uses both the absolute BIS value and its increase following tracheal intubation, can be used to effectively titrate both propofol and sufentanil. A predicted sufentanil Ce of 1.25 ng/ml before and 0.8 ng/ml after sternotomy was associated with the lowest predicted propofol Ce and fewer changes of propofol target. Lower sufentanil concentrations required higher propofol concentrations and more frequent changes of the target propofol concentration and were associated with similar hemodynamic tolerance.

The bilateral superficial cervical plexus block with 0.75% ropivacaine administered before or after surgery does not prevent postoperative pain after total thyroidectomy.

Patients undergoing thyroid surgery need postoperative pain management. Bilateral superficial cervical plexus block by administration of 0.25% bupivacaine with 1:200000 epinephrine at the end of surgery has been shown to improve postoperative analgesia. The objective of this study was to assess the analgesic efficacy in the first 36 postoperative hours after total thyroidectomy of bilateral superficial cervical plexus block with 0.75% ropivacaine administered before the incision or on completion of the surgical procedure. Methods: We performed a prospective double-blinded, randomized controlled trial that compared 3 parallel groups: the CONT group did not receive any block, the PRE group received bilateral superficial cervical plexus block before surgery while under general anesthesia, and the POST group received bilateral superficial cervical plexus block after surgery while under general anesthesia. The study included 111 patients (37 in each group). Postoperative pain was assessed every 4 hours by use of a 0 to 10 numeric rating scale. All patients received paracetamol every 6 hours. Morphine was administered following a standardized protocol if the numeric rating scale was 4 or higher. The main outcome variables were the proportion of patients given morphine during the 36 hours period, pain intensity scores, and morphine consumption. Results: No intergroup differences were observed in terms of percentage of patients who required morphine, morphine delivery, pain scores, and intraoperative opioid consumption. Conclusions: Bilateral superficial cervical plexus block with 0.75% ropivacaine administered before or after surgery does not improve postoperative analgesia after total thyroidectomy.

Precision of noninvasive hemoglobin-level measurement by pulse co-oximetry in patients admitted to intensive care units for severe gastrointestinal bleeds.

Objectives:Measurement of total hemoglobin, based on pulse co-oximetry, is a continuous and noninvasive method that has been principally evaluated in healthy volunteers subjected to hemodilution. We tested the hypothesis that its accuracy could adversely affect patients presenting with severe hemorrhage, which is traditionally associated with increased microvascular tone. Design:Observational study. Setting:Twelve-bed mixed medico-surgical intensive care unit. Patients:Thirty-three patients admitted to our critical care unit for gastrointestinal bleeds were included. Interventions:A spectrophotometric sensor was positioned on the patient’s fingertip and connected to a pulse co-oximeter. During the first 24 hrs following admission, venous hemoglobin level was determined at the laboratory every 8 hrs and was compared with hemoglobin levels displayed on the pulse co-oximeter measurements screen and/or measured from capillary blood using a portable photometer. Measurements and Main Results:The primary end point was the percentage of inaccurate measurements, which were defined as >15% difference compared with reference values or their unavailability for any technical reason. Twenty-five (19%) measurements of pulse co-oximeter measurements were unavailable from the screen. Pulse co-oximeter measurements and capillary hemoglobin levels were significantly correlated to venous hemoglobin level. For venous hemoglobin level compared with pulse co-oximeter measurements (n = 105), and for venous hemoglobin level compared with capillary hemoglobin levels (n = 111), the biases were, respectively, 1.0 ± 1.9 g dL−1 and 0.4 ± 1.0 g dL−1 (p < .05). The proportion of inaccurate measurements was significantly higher for pulse co-oximeter measurements (56% vs. 15%, p < .05). Although the use of norepinephrine did not affect concordance parameters, unavailability of measurements was frequently observed (42% vs. 15%, p < .05). Conclusions:Determination of pulse co-oximetry-based hemoglobin in patients presenting with severe gastrointestinal bleeds can be inaccurate, which renders its use to guide transfusion decisions potentially hazardous. The unavailability of measurements, especially during vasopressor infusion, represents another serious limitation for hemorrhagic patients.

Severe Rhabdomyolysis after Laparoscopic Surgery for Adenocarcinoma of the Rectum in Two Patients Treated with Statins

RHABDOMYOLYSIS is a clinical and biochemical syndrome resulting from skeletal muscle injury with the release of muscle contents into the plasma. It results either form a direct muscle injury or from an altered metabolic relationship between energy production and consumption in muscle. Crush syndrome, extensive burns, electric shock, and prolonged immobilization are the main causes of direct muscle injury. Strenuous physical exercise, malignant hyperthermia, muscle ischemia resulting from compression or vascular injury, infections, myopathies, toxins, and drugs, including alcohol, which accounts for 20% of the cases, can cause nontraumatic rhabdomyolysis. This syndrome has been described with fibrates and statin lipid-lowering drugs, culminating in the recent removal of cerivastatin from the market because of a number of rhabdomyolysis-related deaths. Severe cases were reported in elderly patients and in patients taking lipid-lowering drugs. We observed two consecutive cases of severe postoperative rhabdomyolysis in patients who underwent elective laparoscopic surgery for adenocarcinoma of the rectum, and for whom cumulative risk factors were identified in retrospect: long-term treatment with statins and laparoscopic surgery with prologned immobilization under general anesthesia.

Reproductibilité et interchangeabilité du Thromboélastographe®, Sonoclot® et du temps de coagulation activé (Hémochron®), en chirurgie cardiaque

PURPOSE Despite their common use in cardiac surgery, few studies have evaluated the reproducibility of the Thromboelastograph (TEG), of the Sonoclot (SCT), and of the activated coagulation time with celite (ACT-C) or kaolin (ACT-K) measured with the Hemochron, in clinical conditions of on-site monitoring of hemostasis. This study determined the reproducibility of those measurements, and evaluated the ability of various devices to substitute for the ACT-C. METHODS Blood samples collected from 20 volunteers and 21 patients undergoing myocardial revascularization were analyzed in the two channels of the TEG, in two SCT and four Hemochron analyzers. The overall of TEG and SCT coagulation profiles were analyzed by a computerized TEG and an experienced observer respectively. The variation rate (V%) was calculated for each variable. The ability of ACT-K and SCT to substitute for ACT-C under different clinical conditions was evaluated. RESULTS ACT-C and ACT-K V% ranged between 5.6% and 10.8% and between 6.7% and 12.4% respectively. TEG and SCT V% ranged between 3.1% and 9.5% and between 5.8% and 33.6% respectively, according to different conditions and parameters. In volunteers and non-heparinized patients, the ACT-C and ACT-K were interchangeable. No other test can substitute for the ACT-C when patients are heparinized during cardiopulmonary bypass (CPB). CONCLUSIONS In the clinical conditions of use, on-site hemostasis monitoring devices providing the most reproducible measurements are, in decreasing order, the TEG, the Hemochron and the SCT. In heparinized patients and during CPB, results from different tests are not interchangeable, stressing the importance of establishing appropriate instrument-specific values for monitoring anticoagulation during cardiac surgery.ObjectifMalgré une utilisation courante, la reproductibilité des mesures du Thromboélastographe® (TEG), du Sonoclot® (SCT), et de l’Hémochron® mesurant le temps de coagulation activé avec célite ou kaolin (ACT-C et ACT-K), a été peu étudiée dans les conditions réelles d’utilisation. La présente étude évalue la reproductibilité de ces mesures, et la possibilité de substituer l’ACT-C par un des autres tests.MéthodeLes échantillons sanguins ont été prélevés chez 20 volontaires et 21 patients devant subir une revascularisation myocardique, et analysés dans deux canaux du TEG, deux SCT et quatre Hémochron®. Les tracés du TEG et du SCT ont été analysés respectivement par ordinateur et par un observateur expérimenté. Le pourcentage de variation (V %) pour chaque variable et l’interchangeabilité de l’ACT-K et du SCT avec l’ACT-C ont été évalués.RésultatsLes V % de l’ACT-C et de l’ACT-K varient respectivement de 5,6 % à 10,8 % et de 6,7 % à 12,4 % selon les conditions. Les V % du TEG et du SCT varient respectivement de 3,1 % à 9,5 % et de 5,8 % à 33,6 %, selon les conditions et les paramètres étudiés. Aucun instrument ne peut se substituer à l’ACT-C en présence d’héparine et durant la circulation extracorporelle (CEC). Chez les volontaires et les malades non héparinisés, l’ACT-C et l’ACT-K sont interchangeables.ConclusionDans des conditions réelles d’utilisation en chirurgie cardiaque, les mesures les plus reproductibles sont obtenues, dans un ordre décroissant, avec le TEG, l’Hémochron puis le SCT Les résultats des différents tests ne sont pas interchangeables chez le malade durant la CEC.AbstractPurposeDespite their common use in cardiac surgery, few studies have evaluated the reproducibility of the Thromboelastograph® (TEG), of the Sonoclot® (SCT), and of the activated coagulation time with celite (ACT-C) or kaolin (ACT-K.) measured with the Hemochron®, in clinical conditions of on-site monitoring of hemostasis. This study determined the reproducibility of those measurements, and evaluated the ability of various devices to substitute for the ACTC.MethodsBlood samples collected from 20 volunteers and 21 patients undergoing myocardial revascularization were analyzed in the two channels of the TEG, in two SCT and four Hemochron® analyzers. The overall of TEG and SCT coagulation profiles were analyzed by a computerized TEG and an experienced observer respectively. The variation rate (V%) was calculated for each variable. The ability of ACT-K and SCT to substitute for ACT-C under different clinical conditions was evaluated.ResultsACT-C and ACT-K V% ranged between 5.6% and 10.8% and between 6.7% and 12.4% respectively. TEG and SCT V% ranged between 3.1 % and 9.5% and between 5.8% and 33.6% respectively, according to different conditions and parameters. In volunteers and nonheparinized patients, the ACT-C and ACT-K were interchangeable. No other test can substitute for the ACT-C when patients are heparinized during cardiopulmonary bypass (CPB).ConclusionsIn the clinical conditions of use, on-site hemostasis monitoring devices providing the most reproducible measurements are, in decreasing order, the TEG, the Hemochron® and the SCT. In heparinized patients and during CPB, results from different tests are not interchangeable, stressing the importance of establishing appropriate instrument-specific values for monitoring anticoagulation during cardiac surgery.