Isabelle Alves

University of Lille Nord de France, Lille, Nord-Pas-de-Calais, France

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Publications (3)5 Total impact

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    ABSTRACT: We tested the effects of activated protein C (APC) in macro and microvascular beds within 60 minutes of treatment. Twelve patients treated with APC for severe sepsis were included. We assessed macrovascular reactivity by phenylephrine arterial dose-response. Pharmacological modeling (EC50, Emax and Hill coefficient) and individual dose-response curve were tested. Microvascular reactivity was tested with skin laser-Doppler by using post-occlusive reactive hyperemia (PORH) with measurements of peak, time to peak (Tmax), time to half recovery (T1/2R) and myogenic and sympathetic tones. All measurements were done 30 minutes before, just before and 30 minutes and 60 minutes after APC infusion. Microvascular reactivity was also tested in 8 healthy volunteers. In patients, arterial pressure did not increase significantly. However, 60 minutes after the beginning of APC infusion, reactivity to alpha-1 stimulation was improved: EC50 decreased from 15.3 (0.9-55830) to 3.1 (1.0- 6.2) (p=0.04) and 5/12 patients improved their dose-response curve. As for microcirculatory parameters, as early as 30 minutes after the beginning of APC infusion, PORH peak increased from 102 (40-168) to 162 (35-196) (p=0.04), Tmax was shorter: 30 (14-52) vs 56 (22-83) sec (p=0.03) and the T1/2R also decreased, from 72.4 sec (41.9-134.6) to 49.8 sec (31.0-129.8) (p=0.02). Myogenic tone increased (p=0.03) whereas sympathetic tone decreased (p=0.03) and myogenic tone was lower than controls before but not after APC treatment. In conclusion, APC improves vascular reactivity both at macro- and microcirculatory levels very quickly, suggesting that this is not due to protein synthesis or anticoagulant effect. The myogenic properties of vessels could partly drive this effect.
    Shock (Augusta, Ga.) 09/2013; · 2.87 Impact Factor
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    ABSTRACT: The aim of this study was to evaluate the manual compression of the abdomen (MCA) during expiration as a simple bedside method to detect expiratory flow limitation (EFL) during daily clinical practice of mechanical ventilation (MV). We studied 44 semirecumbent intubated and sedated critically ill patients. Flow-volume loops obtained during MCA were superimposed upon the preceding breaths and recorded with the ventilator. Expiratory flow limitation was expressed as percentage of expiratory tidal volume without any increase in flow during MCA (MCA [%V(T)]). In the first 13 patients, MCA was validated by comparison with the negative expiratory pressure (NEP) technique. Esophageal pressure changes during MCA and intrinsic positive end-expiratory pressure were also recorded in all the patients. Manual compression of the abdomen and NEP agreed in all cases in detecting EFL with a bias of -0.16%. Percentage of expiratory tidal volume without any increase in flow during MCA is highly correlated with percentage of expiratory tidal volume without any increase in flow during NEP (n = 13, P < .0001, r(2) = 0.99) and intrinsic positive end-expiratory pressure (n = 44, P < .001, r(2) = 0.78), with a good repeatability (n = 44; within-subject SD, 5.7%) and reproducibility (n = 13; within-subject SD, 2.41%). Two third of the patients were flow limited, among whom one third had no previously known respiratory disease. Manual compression of the abdomen provides a simple, rapid, and safe bedside reliable maneuver to detect and quantify EFL during mechanical ventilation.
    Journal of critical care 07/2011; 27(1):37-44. · 2.13 Impact Factor
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    ABSTRACT: Acute delirium is a commonly encountered problem in the intensive care unit (ICU), which has a myriad of causes and contributes to poor outcomes. We present the case of an alcoholic critically ill patient who developed prolonged acute ICU delirium wrongly diagnosed as sedation and alcohol withdrawal. Protracted vomiting, swallowing disorders and continuous aspirations prevented him from enteral feeding and discontinuation of mechanical ventilation. After several days, it became clear that the patient had been misdiagnosed. Fortunately, nystagmus and ophthalmoplegia then allowed the recognition of Wernicke's encephalopathy, confirmed by cerebral MRIs. After thiamine supplementation, his state improved but he was discharged only on day 32. Wernicke's encephalopathy is an acute reversible neuropsychiatric emergency, which is falsely considered as uncommon, and is largely misdiagnosed, especially in critically ill patients. Thiamine should be systematically given to all critically ill alcoholic patients, especially those with protracted vomiting.
    Case Reports 01/2009; 2009.