Decreased levels of procoagulant phospholipids in bleeding patients treated by vitamin K antagonists.

International Normalized Ratio (INR) is currently used to monitor vitamin K antagonist therapy, and the bleeding incidence becomes exponential for INR>4.5. Inversely, more than 50% of patients with a supratherapeutic INR are asymptomatic. Therefore it could be of interest to identify patients with a higher bleeding risk. Microparticles derived from different cell types express procoagulant phospholipids (PPL) which can be evaluated by a chronometric coagulation assay where a shortening of the clotting times is associated with increased levels of PPL. In a series of 174 consecutive patients referred to our Emergency Department with an INR>5, median level of PPL was significantly (p=0.004) lower (38.2s) in the 119 asymptomatic patients than in patients with nonmajor (43.6s, n=35) or major bleeding (46.6s, n=19), indicating higher levels of procoagulant phospholipids in asymptomatic patients. By receiver operating characteristic curve analysis, a cut-off of 43.5s discriminated patients with higher haemorrhagic risk (area under the curve=0.648). In contrast, thrombomodulin levels, quantified either by immunological or functional assays were not significantly different between both groups. In conclusion, evaluation of PPL could be of interest to define the haemorrhagic risk of VKA- treated patients.

Efficacy of AccuVein to facilitate peripheral intravenous placement in adults presenting to an emergency department: a randomized clinical trial.

OBJECTIVES: In the emergency department (ED), intravenous (IV) catheter placement is one of the most frequent interventions and may be a real challenge in some conditions. Improvement of the success rate with new technology represents a great opportunity. This randomized controlled trial aimed to show the superiority of AccuVein to cannulate veins in adults compared to routine care. METHODS: After giving written consent, patients were randomized into two groups: routine IV catheter insertion or insertion guided by the AccuVein, which is a hand-held instrument displaying laser light to optimize visualization of veins. The primary outcome was the time to successful placement of catheters. Secondary outcomes included the number of attempts, the rate of failure, technique-related pain, occurrence of movements, and efficiency of IV cannulation as perceived by the operator when using the AccuVein device. Results are given as mean and bootstrapped 95% confidence interval (CI) and percentages. p-values of <0.05 were considered significant. RESULTS: A total of 266 six patients were included, with 157 randomized to routine cannulation and 115 to AccuVein. Patient characteristics were similar. Time to successful placement of IV catheter (routine, 98 seconds, 95% CI = 85 to 113 seconds; and AccuVein, 119 seconds, 95% CI = 93 to 154 seconds) was not different between groups (p = 0.24). Secondary outcomes (failure and pain) did not significantly differ, except for movements, which were more frequent when using the AccuVein device (19.1% vs. 10.2%, p = 0.05). Evaluation of the AccuVein by operators was more often negative than positive. CONCLUSIONS: Use of the AccuVein did not improve IV cannulation in nonselected ED patients.

Non-invasive measurement of hemoglobin: assessment of two different point-of-care technologies.

BACKGROUND: Measurement of blood hemoglobin (Hb) concentration is a routine procedure. Using a non-invasive point-of-care device reduces pain and discomfort for the patient and allows time saving in patient care. The aims of the present study were to assess the concordance of Hb levels obtained non-invasively with the Pronto-7 monitor (version 2.1.9, Masimo Corporation, Irvine, USA) or with the NBM-200MP monitor (Orsense, Nes Ziona, Israel) and the values obtained from the usual colorimetric method using blood samples and to determine the source of discordance. METHODS AND FINDINGS: We conducted two consecutive prospective open trials enrolling patients presenting in the emergency department of a university hospital. The first was designed to assess Pronto-7™ and the second NBM-200MP™. In each study, the main outcome measure was the agreement between both methods. Independent factors associated with the bias were determined using multiple linear regression. Three hundred patients were prospectively enrolled in each study. For Pronto-7™, the absolute mean difference was 0.56 g.L(-1) (95% confidence interval [CI] 0.41 to 0.69) with an upper agreement limit at 2.94 g.L(-1) (95% CI [2.70;3.19]), a lower agreement limit at -1.84 g.L(-1) (95% CI [-2.08;-1.58]) and an intra-class correlation coefficient at 0.80 (95% CI [0.74;0.84]). The corresponding values for the NBM-200MP™ were 0.21 [0.02;0.39], 3.42 [3.10;3.74], -3.01 [-3.32;-2.69] and 0.69 [0.62;0.75]. Multivariate analysis showed that age and laboratory values of hemoglobin were independently associated with the bias when using Pronto-7™, while perfusion index and laboratory value of hemoglobin were independently associated with the bias when using NBM-200MP™. CONCLUSION: Despite a relatively limited bias in both cases, the large limits of agreement found in both cases render the clinical usefulness of such devices debatable. For both devices, the bias is independently and inversely associated with the true value of hemoglobin. TRIAL REGISTRATION: ClinicalTrials.gov NCT01321580 and NCT01321593.