Search PubMed⌕ Search

Biomedical subjects

O Fourcade

Publications and source records attributed to O Fourcade.

At least 19 recordsLinked to original sources
PubMed2006

Assessment of renal function in clinical practice at the bedside of burn patients.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: * In burn patients it has been shown ([2]), that there is a correlation between the creatinine clearance (CL(CR)) and the clearance of inulin. * The CL(CR) has never been studied in burn patients who have normal serum creatinine. * The Robert, Kirkpatrick and sMDRD formulae have never been evaluated in burn patients. WHAT THIS STUDY ADDS: * Despite burn patients having normal serum creatinine concentrations, the study showed that there are large variations in CL(CR) which cannot be detected by single serum creatinine measurements, and which have important implications for drug therapy. * It showed that the formulae currently used to calculate creatinine clearance on the basis of serum creatinine are inadequate for use in burn patients, and they should be abandoned in favour of direct measurement from a 24 h urine collection. AIMS: The aim of this study was to evaluate whether the renal function of burn patients could be correctly assessed using a single serum creatinine measurement, within normal limits, and three prediction equations of glomerular filtration taking into account, serum creatinine, age, weight and sex. METHODS: This was a prospective study comprising 36 adult burn patients with a serum creatinine <120 micromol l(-1), within the second or third week following the burn injury. Renal function was assessed using serum creatinine, 24 h urinary CL(CR), and the Cockcroft-Gault, Robert, Kirkpatrick and simplified MDRD equations. RESULTS: Despite normal serum creatinine concentrations in all patients, a significant number had a decreased CL(CR). The urinary CL(CR) was <80 ml(-1) min(-1) 1.73 m(-2) in nine patients (25%), and <60 ml(-1) min(-1) 1.73 m(-2) in five patients (14%). Between the groups having a CL(CR) lower or greater than 80 ml(-1) min(-1) 1.73 m(-2) there were no differences in gender, burn indices, percentage of mechanically ventilated patients or length of hospital stay, but a difference in age. The highest CL(CR) (>140 ml(-1) min(-1) 1.73 m(-2)) was found in 13 patients younger than 40 years. Regression analysis, residual and Bland-Altman plots revealed that neither the Cockcroft-Gault, Robert, Kirkpatrick nor sMDRD equations were specific enough for the assessment of renal function. CONCLUSIONS: In burn patients with normal serum creatinine during the hypermetabolic phase, serum creatinine and creatine based predictive equations are imprecise in assessing renal function.

Adult↗
PubMed2006

[Characteristics of mepivacaine axillary brachial plexus block performed at 2800 m of altitude].

OBJECTIVE: We evaluated the feasibility and pharmacodynamic profile of axillary brachial plexus nerve blocks performed in high altitude. STUDY DESIGN: A prospective study was performed in healthy volunteers. PATIENTS AND METHODS: Ten male volunteers received 20 ml of 1.5% mepivacaine on radial and median nerves (total 40 ml), first at altitude of 150 then at 2877 m. Onset and offset times for sensory, motor and sympathetic blocks were recorded. Blood was sampled up to 60 min after injection to measure plasma concentrations of mepivacaine. RESULTS: At 150 and 2877 m of altitude, onset times for blocks were similar. Duration of sensory and motor blocks was not different at low and high altitude (193+/-35 min and 180+/-47 min; and 237+/-32 min and 217+/-44 min, respectively). Plasma mepivacaine concentrations were significantly lower at 20 minutes in high altitude (p<0.05). At higher altitude, one patient showed clinical signs of neurological toxicity, with plasma concentrations of mepivacaine ranging from 0.94 to 1.21 mug/ml. CONCLUSION: At altitude of 2877 m, axillary brachial plexus block with 1.5% mepivacaine is feasible, with onset and offset times for sensory and motor effects similar to those performed at 150 m.

Adult↗
PubMed2006

[Subarachnoidal haemorrhage and myocardial failure: interest of cardiac and cerebral monitoring].

Spontaneous subarachnoidal haemorrhage can be associated with neurogenic pulmonary oedema and cardiogenic shock. The presentation is an ischemic myocardial dysfunction associated with normal coronary arteries. Hypoxaemia associated with arterial hypotension on patients with brain injury can worsen neurological outcome. The administration of norepinephrine associated with fluid expansion could be deleterious on cardiac function. We report the case of a patient with acute pulmonary oedema associated with post-aneurysmal subarachnoid haemorrhage managed with transoesophageal Doppler monitoring.

Adult↗
PubMed2006

[Cerebral ischemic threshold in clinical practice].

The ischemic threshold is reached when the availability of oxygen in the cerebral tissue does not cover oxygen requirement. For a patient sedated, with constant PaO(2) and haemoglobin, the cerebral blood flow (CBF) global and local is the essential factor to maintain such a balance. At a cellular level, ischemia occurs when the CBF is below 20-25 ml/min. However, this threshold probably varies with the patient and also within the normal or perilesional tissue. A cerebral perfusion pressure (CPP) of 60 mmHg, recommended for a cerebral perfusion allowing a sufficient CBF for normal brain, does not prevent ischemia. Monitoring aimed to control parameters of the aerobic metabolism (PtiO(2), SjO(2) and microdialysis) and to detect the ischemic threshold allows to adapt the CPP to each patient and continuously.

Brain Ischemia↗
PubMed2006

[Decompressive craniectomy and intracranial hypertension].

Decompressive craniectomy was purposed for the treatment of refractory intracranial hypertension after head injury. This review discusses results obtained by this surgery in severe head trauma. Several studies have confirmed a reduction in intracranial pressure secondary to decompressive craniectomy. Mortality decreased and the proportion of good outcome of the survivors increased. These results have not been confirmed prospectively, and indications have to be clarified. The positive effects of decompressive craniectomy compared to barbiturate or hypocapnia in the "second tier therapy" in refractory intracranial hypertension could be interesting to evaluate.

Craniocerebral Trauma↗
PubMed2006

Double- vs. single-injection infraclavicular plexus block in the emergency setting: higher success rate with lower volume of local anaesthetic.

BACKGROUND AND OBJECTIVES: Infraclavicular plexus block has many advantages of particular interest in the emergency setting. However, the number of nerve stimulations needed to optimize the technique remains unclear. We evaluated both the local anaesthetic requirement and the success rate of Sim's derived infraclavicular plexus block performed with a nerve stimulator when either one or two responses were sought. METHODS: In this prospective study, 50 patients who presented for distal upper limb surgery were randomized into two groups: in Group 1, ropivacaine 0.75% 40 mL was injected when nerve stimulation elicited a distal motor response (median, ulnar or radial). In Group 2, only 30 mL of the same local anaesthetic was injected, 7 mL to the musculocutaneous nerve and 23 mL to the median, ulnar or radial nerves. Sensory and motor blocks were tested at 5-min intervals over 30 min. RESULTS: The time to perform the block was similar in both groups. The success rate of the block increased from 80% in the single-stimulation group to 92% in the double-stimulation group (not significant). The onset time of sensory and motor block was shorter and block extension was greater in ulnar, antebrachial cutaneous and brachial cutaneous nerve distributions in the multistimulation group (P < 0.05). CONCLUSIONS: We conclude that only 30 mL of local anaesthetic seems to be sufficient to ensure a high level of success when performing an infraclavicular block with stimulation of both the musculocutaneous nerve and median, ulnar or radial nerve.

Adult↗
PubMed2006

[Continuous spinal anesthesia for femoral fracture in two patients with severe aortic stenosis].

Neuraxial blockade is usually not recommended in patients with aortic stenosis. However, neuroaxial blockade techniques such as continuous spinal or epidural anaesthesia can be tailored to minimize potentially dramatic consequences of decrease in systemic vascular resistance, often encountered after standard single shot spinal anaesthesia. We report the cases of two severe aortic stenosis patients (aortic valve area<0.5 cm2) that underwent hip surgery under continuous spinal anaesthesia. Small doses of isobaric 0.25% bupivacaine titrated to limit total dose below 5 mg, injected through the intrathecal catheter allowed the control of haemodynamic parameters. No clinical complication occurred in these two patients.

Aged, 80 and over↗
PubMed2005

Propacetamol and ketoprofen after thyroidectomy.

BACKGROUND AND OBJECTIVE: The combination of non-opioid analgesic drugs, though widely used, has been rarely evaluated. The aim of this study was to compare the efficacy of propacetamol and the non-steroidal analgesic drug ketoprofen, alone or in combination, on pain relief after thyroid surgery performed using remifentanil. METHODS: Ninety-seven patients were randomly allocated to one of the three groups: propacetamol 2 g (32), ketoprofen 100 mg (33) and propacetamol 2 g + ketoprofen 100 mg (32). Each regimen was administered intravenously (i.v.) 30 min before the end of surgery and then every 6 h. If pain was not relieved, patients received an i.v. bolus of tramadol 100 mg. Tramadol consumption and pain intensity using a visual analogue scale was recorded at 1, 2, 8 and 14 h after the end of surgery. RESULTS: Pain scores were significantly higher with propacetamol compared with ketoprofen 2 h after surgery (35 +/- 3.7, 21 +/- 2.6, respectively; P < 0.01). The number of patients receiving tramadol was higher with propacetamol alone compared with the two other groups, 1 h (14/32, 4/33, 2/32, respectively; P > 0.01) and 2 h (24/32, 6/33, 8/32, respectively; P < 0.01) after surgery. There was no difference between ketoprofen alone and ketoprofen plus propacetamol, and there was no difference between the three groups from the 8th hour onward. CONCLUSIONS: In the immediate postoperative period after thyroid surgery performed using remifentanil, the concomitant use of propacetamol and ketoprofen does not improve analgesia compared with ketoprofen alone.

Acetaminophen↗
PubMed2003

Spinal anaesthesia in a child with hypoplastic left heart syndrome.

Hypoplastic left heart syndrome (HLHS), a complex congenital heart disease, is the most common lethal cardiac defect in neonates. Its treatment includes cardiac transplantation and/or surgical palliation. Associated extracardiac congenital abnormalities are exceptional. We report the case of a neonate with HLHS and anorectal atresia who required urgent surgical management to relieve intestinal obstruction. The surgery was successfully performed under spinal anaesthesia.

Anesthesia, Spinal↗
PubMed1999

New developments in phospholipase A2.

Some of the most recent data concerning various phospholipases A2, with special emphasis on secretory, cytosolic, and calcium-independent phospholipases A2 are summarized. Besides their contribution to the production of proinflammatory lipid mediators, the involvement of these enzymes in key cell responses such as apoptosis or tumor cell metastatic potential is also discussed, taking advantage of transgenic models based on gene invalidation by homologous recombination. The possible role of secretory and cytosolic platelet-activating factor acetyl hydrolases is also briefly mentioned. Finally, the ectopic expression in epididymis of an intestinal phospholipase B opens some novel issues as to the possible function of phospholipases in reproduction.

Animals↗
PubMed1999

Membrane sidedness of biosynthetic pathways involved in the production of lysophosphatidic acid.

Lysophosphatidic acid (LPA) is a novel phospholipid mediator with diverse biological activities such as smooth muscle contraction, and proliferative effects or modifications of cytoskeleton. Activated blood platelets are the best identified source, explaining accumulation of LPA in serum upon blood coagulation. However, the metabolic pathways responsible for LPA synthesis are still poorly known. Using a model of human erythrocytes treated with the calcium ionophore A23187, we have shown that type II secretory phospholipase A2 (sPLA2) is able to produce LPA by hydrolyzing phosphatidic acid exposed on the cell surface after phospholipid scrambling. A similar mechanism does not appear to occur in platelets, where inhibitors of sPLA2 or genetic lack of the enzyme do not modify LPA production. However, this does not definitely eliminate the possibility that LPA is also produced in platelets in the external leaflet of the membrane by other phospholipases, which have to be better characterized.

Animals↗
PubMed1998

Regulation of secretory type-II phospholipase A2 and of lysophosphatidic acid synthesis.

Secretory non-pancreatic phospholipase A2 (sPLA2), also called type II-PLA2, is produced in large amounts under inflammatory conditions, thus accumulating in inflammatory fluids. Since the enzyme is virtually inactive on phospholipids from intact cells, we have searched for conditions allowing the action of sPLA2 on membrane phospholipids. Based on an in vitro model, our studies suggest that only those membranes where the transverse distribution of phospholipids has been disturbed offer a convenient surface able to interact with the enzyme, which then achieves significant degradation of all glycerophospholipids. This results in the accumulation of various lysophospholipids such as lysophosphatidylcholine, lysophosphatidylethanolamine and lysophosphatidylserine. However, lysophosphatidic acid (LPA) can also be generated under these conditions involving accumulation of phosphatidic acid in the cytoplasmic leaflet of the membrane, followed by its transfer to the outer monolayer. Since LPA is now considered as a novel phospholipid mediator, this pathway deserves further studies concerning mainly platelets, the main source of LPA identified so far.

Animals↗