Rotation thromboelastometry detects thrombocytopenia and hypofibrinogenaemia during orthotopic liver transplantation.

BACKGROUND: Orthotopic liver transplantation can be associated with haemorrhage, particularly in patients with severe liver dysfunction. We assessed the value of rotation thromboelastometry (ROTEM) to monitor coagulation in the operating theatre, its correlation with routine laboratory findings, and its ability to guide platelet (Plt) and fibrinogen (Fg) transfusion. METHODS: Twenty-three patients were included in this prospective observational study. Laboratory tests and ROTEM tests (EXTEM, INTEM, FIBTEM, and APTEM) were performed six times during the procedure. Correlations between laboratory findings and ROTEM parameters were sought. Thresholds for ROTEM parameters were determined with receiver-operating characteristic (ROC) curve analysis according to Plt count and Fg levels. RESULTS: Clot amplitude at 10 min (A10) of EXTEM was well correlated with Plt count and Fg levels (R(2)=0.46 and 0.52, respectively, P<0.0001). FIBTEM A10 was correlated with Fg (R(2)=0.55, P<0.0001). ROC analysis showed that EXTEM A10 with a threshold of 29 mm predicted thrombocytopenia with a sensitivity of 79% and a specificity of 60%, and a threshold of 26 mm predicted hypofibrinogenaemia with a sensitivity of 83% and a specificity of 75%. CONCLUSIONS: ROTEM is useful for the global assessment of coagulation in the operating theatre. EXTEM was the most informative for assessing the whole coagulation process and A10 showed value in guiding Plt and Fg transfusion.

Validation of a bedside activated clotting time test (Hemochron Jr II Signature) with low dose heparin therapy.

The purpose of this study was to validate a device designed to measure activated clotting time in low-range heparin plasma concentrations (ACT-LR) prospectively during the post-operative period of vascular surgery. Measurement of ACT-LR and activated partial thromboplastin time (APTT) were performed before heparinisation (T0) and at the end of surgery (T1). ACT-LR(T1) and DeltaACT-LR (defined as ACT-LR(T1) - ACT-LR(T0)) were evaluated as diagnostic tests for excessive anticoagulation, defined by APTT more than twice the laboratory's normal, by Bland-Altman method and receiver operating characteristic (ROC) curves. In 103 patients, mean (SD) ACT-LR was 137 (33) s at T0 and 176 (39) s at T1. Bland-Altman graph did not show a good agreement between APTT and ACT-LR. Areas under ROC curves were 0.82 (95% CI: 0.75-0.89) and 0.87 (95% CI: 0.80-0.93) for ACT-LR(T1) and DeltaACT-LR, respectively. Using a threshold of 32 s for DeltaACT-LR, test sensitivity was 87% (95% CI: 81-93%), specificity was 85% (95% CI: 78-92%), positive predictive value was 90% (95% CI: 84-96%) and negative predictive value was 81% (95% CI: 73-86%). While DeltaACT-LR may have some potential in evaluating excessive anticoagulation in vascular surgery, the poor correlation between ACT-LR and APTT does not support its routine use.

Liver Transplantation With Old Grafts: A Ten-Year Experience.

BACKGROUND: The persistent scarcity of donors has prompted liver transplantation teams to find solutions for increasing graft availability. We report our experience of liver transplantations performed with grafts from older donors, specifically over 70 and 80 years old. PATIENTS AND METHODS: We analyzed our prospectively maintained single-center database from January 1, 2005, to December 31, 2014, with 380 liver transplantations performed in 354 patients. Six groups were composed according to donor age: <40 (n = 84), 40 to 49 (n = 67), from 50 to 59 (n = 62), from 60 to 69 (n = 76), from 70 to 79 (n = 64), and ≥80 years (n = 27). RESULTS: Donors <40 years of age had a lower body mass index, died more often from trauma, and more often had cardiac arrest and high transaminase levels. In contrast, older donors (≥70 years of age) died more often from stroke. Recipients of grafts from donors <50 years of age were more frequently infected by hepatitis C virus; recipients of oldest grafts more often had hepatocellular carcinoma. Cold ischemia time was the shortest in donors >80 years of age. Patient survival was not significantly different between the groups. In multivariate analysis, factors predicting graft loss were transaminase peak, retransplantation and cold ischemia time but not donor age. CONCLUSIONS: Older donors >70 and >80 years of age could provide excellent liver grafts.

[Target-controlled infusion of propofol for intraoperative sedation: determination of effect-site concentration and assessment of bispectral index]. / Sédation peropératoire à objectif de concentration avec le propofol: détermination des concentrations au site d'action et évaluation de l'index bispectral.

OBJECTIVES: To determine the effect-site concentration (Ce) of propofol, required to achieving adequate sedation. To assess the efficacy and safety of a target-controlled infusion system during monitored anaesthesia care and to evaluate the ability of bispectral index (BIS) to predict sedation level. Study design. - Prospective clinical study. PATIENTS: Women scheduled for insertion of tension-free vaginal tape under local anaesthetic infiltration. METHODS: After premedication with hydroxyzine, 1% propofol was infused using the Diprifusor system at an initial target plasma concentration (Cc) of 1 microg/ml and then adjusted by steps of 0.2 microg/ml at 5 min intervals. The level of sedation was assessed using the observer's assessment of alertness/sedation (OAA/S) scale; the objective was to obtain an OAA/S level at 4 or 3 (response to verbal stimulation). Ce of propofol and BIS were noted every 5 min. Relation between Ce or BIS and OAA/S scale was analysed by linear regression and probability of prediction (P(K)). RESULTS: Fifty patients aged 62 +/- 12 years were studied. Sedation at level 4 or 3 was observed in all patients. Ce of propofol and BIS to maintain this OAA/S score were, respectively, 1.0 +/- 0.2 microg/ml and 87 +/- 7. There was a linear relation between OAA/S scale and BIS or Ce; however, individual values demonstrate wide variability. The average of P(K) values computed for each patient for the BIS and Ce was 0.84 and 0.83, respectively. CONCLUSIONS: Target-controlled infusion of propofol provides easy and safe management of intraoperative sedation, allowing a fast and precise adjustment of the propofol concentration to the clinical response of the patient.

[Severe acute hepatic failure and haemophagocytic syndrome: cause or consequence?]. / Insuffisance hépatique aiguë sévère et syndrome d'activation macrophagique: cause ou conséquence?

Haemophagocytic syndrome corresponds to an unconnected macrophagic activity with haemophagocytosis. We report the case of a haemophagocytic syndrome in a 49-year-old woman with initially a severe acute hepatic failure. This syndrome is probably underestimated in ICU patients. Haemophagocytic syndrome should be suspected in patients with fever and jaundice without infection.

Risk factors for bleeding and transfusion during orthotopic liver transplantation.

OBJECTIVE: While orthotopic liver transplantation (OLT) can be associated with haemorrhage, the risk factors for bleeding and transfusion remain difficult to predict. Perioperative transfusion has potentially deleterious side effects and impairs graft and patient survival. Preoperative identification of patients at high risk of bleeding is of clinical interest to manage perioperative transfusion and blood product storage. STUDY DESIGN: Retrospective study. PATIENTS AND METHODS: All OLT conducted between 2004 and 2008 in the University Hospital of Bordeaux were studied. Risk factors for bleeding greater than one blood volume and for massive red blood cell (RBC) transfusion were determined using univariate and multivariate analysis. Thresholds were determined with ROC curve analysis. RESULTS: One hundred and forty-eight transplantations were studied. Preoperative haemoglobin and Child class A were independent protective risk factors for bleeding greater than one blood volume (OR 0.81 [0.67-0.98] and 0.27 [0.10-0.72], respectively). Preoperative Hb was a protective risk factor (OR 0.71 [0.58-0.88]) whereas history of oesophageal varicose bleeding was a risk factor (OR 4.67 [1.45-15.05]) for transfusion of more than eight RBC. CONCLUSION: Risk factors for bleeding and transfusion during OLT identified in this study were of little clinical usefulness so blood products should always be available during the procedure.

Continuous non-invasive arterial pressure measurement: evaluation of CNAP device during vascular surgery.

OBJECTIVE: Standard non-invasive blood pressure (BP) monitoring is an intermittent, discontinuous procedure. Beat-to-beat BP monitoring requires invasive measurement via an arterial catheter and may be associated with serious complications. The Infinity CNAP SmartPod (Dräger Medical AG & Co. KG, Lübeck, Germany) has recently been proposed for non-invasive continuous beat-to-beat BP measurements. The present study was designed to compare BP obtained with the CNAP and with an invasive method in the operating room. STUDY DESIGN: Prospective study. PATIENTS AND METHODS: Twenty-five patients undergoing major vascular surgery were included. Systolic, mean and diastolic BP were monitored invasively (SAP, MAP and DAP respectively) and not invasively using the CNAP (CNAP-S, CNAP-M and CNAP-D respectively). Measurements were performed intraoperatively every minute during 1 hour. RESULTS: One thousand and five hundred pairs of simultaneous CNAP and invasive BP measurements were obtained and 148 were eliminated. The range of BP measurements was 63-205 mmHg for SAP and 57-187 mmHg for CNAP-S, 38-143 mmHg for MAP and 43-142 mmHg for CNAP-M, 29-126 mmHg for DAP and 33-121 mmHg for CNAP-D. Bias and 95% limit of agreement between CNAP and invasive BP measurements were respectively 7.2 and -17.7 to 32.2 mmHg for SAP, -1.8 and -22.0 to 18.3 mmHg for MAP, and -7.5 and -27.3 to 12.4 mmHg for DAP. The percentage of CNAP measurements with a bias <10% with the arterial line was 69%, 86% and 91% for systolic, diastolic and mean pressures, respectively. CONCLUSION: Despite low accuracy for SAP and DAP measurements, CNAP system seems more accurate for MAP measurement in patients undergoing vascular surgery.

[Cranial subdural haematoma after spinal anaesthesia treated by blood patch]. / Hématome sous-dural aigu intracrânien après rachianesthésie traité par blood patch.

The authors report a case of subdural haematoma after spinal anaesthesia. A 36-year-old woman underwent phlebectomy under spinal anaesthesia. Two days later, she complains of severe headache without neurological signs, not responding to bed rest and analgesics. Magnetic resonance imaging showed a small acute subdural haematoma in the right parieto-occipital region. On the forth day, she was given a blood-patch, which improved rapidly the patient. Recovery was complete.

[Mitochondria in anaesthesia and intensive care]. / La mitochondrie: rôles et implications en anesthésie-réanimation.

OBJECTIVE: Mitochondria play a key role in energy metabolism within the cell through the oxidative phosphorylation. They are also involved in many cellular processes like apoptosis, calcium signaling or reactive oxygen species production. The objectives of this review are to understand the interactions between mitochondrial metabolism and anaesthetics or different stress situations observed in ICU and to know the clinical implications. DATA SOURCES: References were obtained from PubMed data bank (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi) using the following keywords: mitochondria, anaesthesia, anaesthetics, sepsis, preconditioning, ischaemia, hypoxia. DATA SYNTHESIS: Mitochondria act as a pharmacological target for the anaesthetic agents. The effects can be toxic like in the case of the local anaesthetics-induced myotoxicity. On the other hand, beneficial effects are observed in the anaesthetic-induced myocardial preconditioning. Mitochondrial metabolism could be disturbed in many critical situations (sepsis, chronic hypoxia, ischaemia-reperfusion injury). The study of the underlying mechanisms should allow to propose in the future new specific therapeutics.

Pressure support ventilation during inhalational induction with sevoflurane and remifentanil in adults.

BACKGROUND AND OBJECTIVE: The purpose of this prospective randomized study was to assess the value of pressure support ventilation during inhalational induction with sevoflurane in adult patients. METHODS: Thirty-five adult patients, ASA I-II and scheduled for ear nose throat surgery were studied. Vital capacity induction with 8% sevoflurane in 8 L min-1 oxygen was performed. Pressure support ventilation was used in Group 1 with pressure set at 15 cmH2O. In Group 2, patients breathed spontaneously. After 2 min, sevoflurane was set to 3% and remifentanil 1 microg kg(-1) was injected over 2 min followed by an infusion of 0.1 microg kg(-1) min(-1). Two minutes after the end of the bolus, intubation was performed. Bispectral index, oxygen saturation, respiratory rate, end-tidal carbon dioxide, expired tidal volume and expired sevoflurane concentration were recorded every minute. RESULTS: Eighteen patients were included in Group 1 and 17 in Group 2. Saturation, respiratory rate and end-tidal carbon dioxide were similar in the two groups. Expired tidal volume was significantly higher and bispectral index values significantly lower in Group 1. Intubating conditions were better in Group 1. CONCLUSIONS: Pressure support ventilation provides both better ventilation and deeper level of anaesthesia during inhalation induction with sevoflurane.