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F Sztark

Publications and source records attributed to F Sztark.

At least 19 recordsLinked to original sources
PubMed2006

[Microparticles during sepsis and trauma. A link between inflammation and thrombotic processes].

Sepsis and trauma lead to a sustained activation of monocytes and endothelium. In the vascular compartment, stimulated cells release microparticles. Circulating MP provide an additional procoagulant phospholipid surface enabling the assembly of the clotting enzymes complexes and thrombin generation. Their procoagulant properties rely on the exposition of phosphatidylserine, made accessible after cell stimulation and on the possible presence of tissue factor, the main cellular initiator of blood coagulation. Microparticles constitute the main reservoir of blood-borne tissue factor activity. At sites of endothelium injury, enhanced release or recruitment of procoagulant MP through P-selectin-PSGL-1 pathway could concentrate TF activity above a threshold allowing blood coagulation to be triggered. Converging evidences from experimental or clinical data highlight a role for MP harboring tissue factor in the initiation of disseminated intravascular coagulopathy. In these settings, the pharmacological modulation of MP levels or biological functions through activated protein C or factor VIIa allows challenging issues.

Apoptosis↗
PubMed2006

[Use of activated recombinant FVII in the control of haemorrhage following trauma].

Uncontrolled haemorrhage is a major cause of death in trauma patients: sometimes inaccessible to surgery and often associated with coagulopathy. We report a case of severe blunt pelvic trauma associated with suicide. The conventional treatments were unsuccessful and embolization was impossible. The patient required massive blood product transfusion. A 100 microg/kg recombinant activated factor VII dose was infused, twice. After administration of the first dose, the blood requirement decreased dramatically. Further work and trials are required to assess the safety profile and dose regimen for this drug.

Coagulants↗
PubMed2006

[Controlled hypernatremia].

Hypernatremia exerts its main effect on the brain through the osmotic gradient it creates on either side of the blood brain barrier, which is impermeable to sodium. This generates a transfer of water from the intracellular to the vascular sector leading to temporary cell shrinkage. Osmoregulation permits cerebral cells to accumulate osmoactive molecules in order to restore their initial volume. It has been demonstrated in animals with brain injury that intracellular dehydration occurs essentially in the nonlesioned hemisphere. In most experimental studies, the reduction in cerebral volume obtained by hypertonic saline (HS) perfusion is accompanied by an intracranial pressure decrease, even under hemorrhagic shock conditions. Initially, clinical studies successfully used HS, as an alternative to mannitol, in the treatment of acute and refractory intracranial hypertension. Then continuous infusion of HS, with the objective of inducing hypernatremia, had produced encouraging effects on intracranial pressure control. However, these results were limited to non-randomized studies, without control groups and mainly in pediatric patients. Nevertheless, the use of HS on intracranial hypertension, refractory to conventional treatments, could be reasonable under strict monitoring of natremia as well as its adverse effects.

Animals↗
PubMed2005

[Heat stroke and fulminans hepatitis: is MARS system relevant?].

Exertional heat stroke (EHS) is a life-threatening condition caused by an extreme elevation in core body temperature. Acute liver failure has been reported during EHS justifying liver transplantation in some cases. The Molecular Adsorbent Recirculating System (MARS) could be indicated in such situations. We report a case of a 58-year old patient who suffered acute liver failure occurring after EHS. The patient was referred for liver transplantation and benefited of MARS therapy. After three sessions of MARS, liver function improved progressively and the transplantation was not necessary. The patient completely recovered.

Bilirubin↗
PubMed2005

[Induction of anaesthesia with target-controlled inhalation of sevoflurane in adults with the ZEUS anaesthesia machine].

OBJECTIVES: To evaluate if the new anaesthesia platform ZEUS (Dräger Medical) allows the induction of anaesthesia with target-controlled inhalation of sevoflurane. STUDY DESIGN: Prospective clinical study. PATIENTS: Adult ASA I or II patients scheduled for elective surgery under general anaesthesia. METHODS: After preoxygenation during 3 min at 100% oxygen, patients were asked to breathe normally; the target end-tidal concentration of sevoflurane was fixed at 4% without priming of the circuit. Sufentanil (target concentration 0.5 ng/ml) was administered 40 s after. RESULTS: Ten patients (48+/-22 yrs) were included. Sevoflurane was detected in the circuit after 36+/-5 s; the target end-tidal concentration of sevoflurane was obtained at 130+/-19 s. Loss of consciousness was observed after 119+/-7 s. The induction was achieved in all patients without any incident. CONCLUSION: This new anaesthesia system make available the induction of anaesthesia with sevoflurane without priming of the circuit.

Adult↗
PubMed2005

Comparison of the anaesthetic requirement with target-controlled infusion of propofol to insert the laryngeal tube vs. the laryngeal mask.

BACKGROUND AND OBJECTIVE: The target effect-site concentration of propofol to insert a laryngeal mask airway was recently reported as almost 5 microg mL(-1). The present study aimed to determine the target effect-site concentration with target-controlled infusion of propofol to place classical larnygeal mask airway or current laryngeal tube in adult patients. METHODS: We included 40 patients scheduled for short gynaecological and radiological procedures under general anaesthesia in a randomized, double-blind manner using the Dixon's up-and-down statistical method. Monitoring included standard cardiorespiratory monitors, and bispectral index monitoring was used for all patients. Anaesthesia was conducted with a target-controlled infusion system: Diprifusor. The initial target plasma concentration of propofol was 5 microg mL(-1), and was changed stepwise by 0.5 microg mL(-1) increments according to Dixon's up-and-down method. Criteria for acceptable insertion were: Muzi's score < or = 2, and mean arterial blood pressure, heart rate or bispectral index variation <20% the baseline values. RESULTS: Target effect-site concentration of propofol required to insert laryngeal tube was 6.3 +/- 0.3 microg mL(-1) with Dixon method and ED50 was 6.1 microg mL(-1) (5.9-6.4) with logistic regression method. In the case of larnygeal mask airway they were 7.3 +/- 0.2 microg mL(-1) (Dixon method) and 7.3 microg mL(-1) (7.1-7.5; with logistic regression) respectively (P < 0.05). ED95 (logistic regression) was 6.8 microg mL(-1) (5.9-7.6) for laryngeal tube and 7.7 microg mL(-1) (7.3-8.0) for larnygeal mask airway (P < 0.05). Haemodynamic incidents were 55% in the larnygeal mask airway group vs. 30% in the laryngeal tube group (P < 0.05). CONCLUSIONS: The target effect-site concentration of propofol for insertion of laryngeal tube was lower than for larnygeal mask airway (P < 0.05), with a consequent reduction of the propofol induced haemodynamic side-effects.

Adolescent↗
PubMed2005

Concentration of remifentanil needed for tracheal intubation with sevoflurane at 1 MAC in adult patients.

BACKGROUND AND OBJECTIVE: Inhalation induction with sevoflurane provides acceptable conditions for tracheal intubation. Opioids significantly decrease the alveolar concentration needed to achieve tracheal intubation. The purpose of this study was to determine the target concentration of remifentanil providing excellent conditions for tracheal intubation with sevoflurane at 1 minimum alveolar concentration without muscle relaxant. METHODS: Twenty-four consecutive patients, aged 18-50 yr, ASA I or II, were studied. Induction of anaesthesia was performed with sevoflurane at age-adjusted minimum alveolar concentration. Remifentanil was simultaneously administered using target-controlled infusion with the Minto model. Target plasma concentration of remifentanil was selected for each patient according to an up-and-down method. RESULTS: The mean target concentration of remifentanil for successful tracheal intubation was 3.3 ng mL(-1) (95% confidence interval: 2.6-3.9 ng mL(-1)). Arterial pressure, heart rate and bispectral index did not increase after tracheal intubation in the group of patients with successful intubation. CONCLUSIONS: Remifentanil at 3.3 ng mL(-1) together with sevoflurane at 1 minimum alveolar concentration provides excellent conditions for tracheal intubation in 50% of patients.

Adolescent↗
PubMed2004

[Protocol for advanced prehospital emergency care of severe head injury].

OBJECTIVES: To analyze the frequency of systemic factors leading to secondary brain insults in victims of serious head trauma in a prehospital setting and to evaluate a protocol for the advanced prehospital emergency care by mobile intensive care unit (i.e., the French Samu-Smur system). STUDY DESIGN: Prospective study, over a period of 24 months. PATIENTS AND METHODS: This prospective study involved 60 victims of severe head injuries (with the exception of polytrauma patients). Tracheal intubation was performed on each patient under direct laryngoscopy and after induction of anaesthesia (fentanyl-etomidate-rocuronium). Controlled ventilation and vascular loading (objectives: SpO(2) >or= 97%, PETCO(2) between 30 and 35 mmHg, SAP >or= 90 mmHg) were administered. RESULTS: Hypoxaemia was found to be the most frequent cause of secondary insults (57% of patients with SpO(2) < 97%). In the case involving an accident that occurred 17 km from the hospital (with extremes of 6-65 km), the speed of medical intervention was note-worthy: tracheal intubation was performed 50 min after the accident, and the patient was admitted into a trauma centre 101 min after impact (median). However, faster intervention could be obtained if the transmission of the alert was improved. The conditions under which the tracheal intubation was performed were found to be satisfactory (difficult intubation 1.6%) without deteriorating the haemodynamic status. This is probably related to the use of muscle relaxants and the choice of etomidate as the first line hypnotic in the prehospital emergency care.

Adolescent↗
PubMed2004

[Severe acute hepatic failure and haemophagocytic syndrome: cause or consequence?].

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.

Aged↗
PubMed2004

[Target-controlled infusion of propofol for intraoperative sedation: determination of effect-site concentration and assessment of bispectral index].

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.

Aged↗
PubMed2001

[Recovery of neuromuscular block after continuous infusion of cisatracurium in patients with renal dysfunction].

OBJECTIVE: Study of the recovery of neuromuscular block after continuous infusion of cisatracurium in patients with renal dysfunction. STUDY DESIGN: Prospective case-control study. PATIENTS: Forty adult patients scheduled for urological surgery were assigned to two groups according to the creatinine clearance (CC) as a measure of the renal function: group IR (CC < 60 mL.min-1) or group NR (CC > or = 60 mL.min-1). METHODS: After premedication with hydroxyzine, anaesthesia was induced with propofol, sufentanil and cisatracurium (0.15 mg.kg-1), and maintained using isoflurane, sufentanil and a continuous infusion of cisatracurium (0.12 mg.kg-1.h-1) adjusted for maintained a post-tetanic count < or = 5. Neuromuscular transmission was monitored at the adductor pollicis using accelerography (TOF Gard). Onset and recovery times in both groups were compared using Student's t test. RESULTS: Infusion time and total dose of cisatracurium were comparable in both groups. Onset times were 3.9 +/- 0.8 min and 3.5 +/- 0.6 min in groups IR and NR respectively. After the infusion, the time to train-of-four ratio of 0.8 were not different in both groups: 77 +/- 18 min (group IR) and 73 +/- 13 min (group NR). However, the spontaneous recovery intervals 25%-75% were delayed in group IR (20 +/- 9 min vs 14 +/- 5 min p < 0.05). CONCLUSION: There are minor differences in the pharmacodynamics of cisatracurium between patients with normal or impaired renal function. Nevertheless, a marked interindividual variability in the recovery parameters was observed in patients with renal dysfunction.

Adult↗
PubMed2000

Determination of sevoflurane alveolar concentration for tracheal intubation with remifentanil, and no muscle relaxant.

The sevoflurane alveolar concentration needed for tracheal intubation with remifentanil was studied in 26 adult patients premedicated with 100 mg hydroxyzine. Anaesthesia was induced with sevoflurane in oxygen. The concentration was determined by Dixon's up-and-down method. The first patient was tested at 4.5%. One minute after obtaining the preselected value, remifentanil 1 microg.kg-1 was injected for 60 s followed by an infusion of 0.25 microg.kg-1. min-1. Ventilation was then manually assisted for 2 min and tracheal intubation was attempted. Tracheal intubation conditions and responses to intubation were noted. Heart rate and mean arterial pressure were recorded before induction, before remifentanil injection, and before and 3 min after tracheal intubation. The concentration for acceptable intubating conditions was 2.5 +/- 0.7%. From logistic regression, ED50 and ED95 were 2.0% (95% CI 1.3-2.5) and 3.2% (95% CI 2.6-5.6), respectively. With sevoflurane 2.5%, heart rate and mean arterial pressure decreased by 18% and 15%, respectively, after remifentanil administration and increased slightly after tracheal intubation.

Adolescent↗
PubMed2000

Absence of stereospecific effects of bupivacaine isomers on heart mitochondrial bioenergetics.

BACKGROUND: Highly lipophilic local anesthetics interfere with mitochondrial energy metabolism. These metabolic effects could, in part, explain some toxic effects of local anesthetics, such as bupivacaine-induced myocardial depression. The purpose of this study was to compare the optically pure isomers of bupivacaine on heart mitochondrial bioenergetics. METHODS: Both bupivacaine enantiomers were tested on rat heart isolated mitochondria. Oxygen consumption, adenosine triphosphate synthesis, and enzymatic activities of the four complexes of the respiratory chain were measured. RESULTS: No significant differences were found between R(+)- and S(-)-bupivacaine on mitochondrial oxidative phosphorylation with a similar dose-dependent decrease in adenosine triphosphate synthesis. Complex I (nicotinamide adenine dinucleotide ubiquinone reductase) was the enzymatic complex of the respiratory chain most sensitive to the bupivacaine isomers. Half-inhibitory concentrations for R(+)- and S(-)-bupivacaine were not statistically different (3.3 +/- 0.4 mm and 2.8 +/- 0.6 mm, respectively). CONCLUSIONS: No stereospecific effects of bupivacaine enantiomers were shown in the inhibition of complex I activity and uncoupling of oxidative phosphorylation. This can be correlated with the lack of stereospecific effects of bupivacaine on myocardial depression. The lipid solubility of local anesthetics appears to be the principal physicochemical factor affecting the potency of these tertiary amines on mitochondrial bioenergetics.

Adenosine Triphosphate↗
PubMed2000

Mitochondrial energy metabolism in brain-dead organ donors.

OBJECTIVES: Change from aerobic to anaerobic metabolism has been described in brain-dead organ donors (BDOD) managed for organ procurement. Such modifications could lead to a depletion in intracellular adenine nucleotides and in part explain primary graft dysfunction. The purpose of this study was to investigate the mitochondrial energy metabolism in BDOD using permeabilized muscle fibers. METHODS: With institutional approval, the study was performed prospectively in 15 consecutive BDOD. In each patient, muscle biopsy and blood samples for the determination of plasma lactate and pyruvate were obtained just before organ removal. Mitochondrial respiratory parameters of skeletal muscle were determined in saponin-skinned muscle fibers. Mitochondrial oxygen consumption rates were measured polarographically using different substrates and inhibitors of the respiratory chain complexes. Results were compared to those obtained from muscle biopsies performed in 10 healthy patients during orthopedic surgery. RESULTS: Fifteen donors, 13 men and 2 women, aged 35 +/- 11 yrs, were studied. All patients had a high lactate-to-pyruvate ratio (10). Mitochondrial respiration rates were significantly decreased during adenosine triphosphate (ATP) synthesis. CONCLUSIONS: Major changes in energy metabolism occurred during brain death with a decrease in ATP synthesis capacity. High-risk donors should be recognized for a better graft evaluation.

Adenosine Triphosphate↗
PubMed1999

[Patient-controlled sedation with propofol for extracorporeal shock wave lithotripsy].

OBJECTIVE: Evaluation of patient-controlled sedation with propofol for extracorporeal shock wave lithotripsy (ESWL) using an EDAP LT01 lithotriptor. STUDY DESIGN: Prospective clinical study. PATIENTS: Fifty consecutive patients, ASA I or II, aged 18-65 years. METHODS: Patients received 50 mg of propofol five minutes before ESWL, then they self-administered 50 mg bolus doses of propofol with a ten minutes lock-out interval. Pain (1-100 mm VAS) and sedation (four points scale) were assessed every five minutes. Patient satisfaction was recorded at the end of the procedure. Pharmacokinetic simulation was done with the Marsh's data set. RESULTS: Three patients were excluded. Patients received a mean propofol dose of 147 +/- 68 mg during the procedure with a mean duration of 47 +/- 8 minutes. The median of the higher sedation scores was 2 (drowsy) and mean maximal VAS was 40 +/- 20 mm (10-70). No complications were recorded. Thirty-nine patients (83%) were satisfied or very satisfied by patient-controlled sedation. CONCLUSION: Patient-controlled sedation with propofol is a safe and efficient mode of administration of an hypnotic agent for ESWL.

Adult↗
PubMed1999

[Cellular energy metabolism: physiologic and pathologic aspects].

Cellular homeostasis requires permanent energy production and consumption. Adenosine triphosphate (ATP) is the major energy component for the cell. Its synthesis occurs mainly in mitochondria where the oxidative phosphorylations realise the coupling between oxygen consumption and phosphorylation of adenosine diphosphate. The anaerobic production of ATP plays an important role in the intermediary metabolism. The enzymatic complexes of the mitochondrial respiratory chain are energy transducers acting as proton pumps. In cardiomyocytes, the phosphocreatine circuit allows a substrate channelling between mitochondria and myofibrils. This metabolic compartmentation explains the difficulties of studying energetic metabolism in the beating heart and the lack of correlation between cardiac function and the usual energy parameters. Mitochondria are a potential site of action of anaesthetic agents. Lipophilic local anaesthetics impair cellular energy metabolism and mitochondrial ATP production. Such effects could be associated with toxic effects of these molecules. NMR or near-infrared spectroscopy are non invasive techniques for monitoring energetic metabolism in vivo. Clinical applications are developed for analysing brain, muscle or cardiac function in physiological and pathological conditions.

Adenosine Triphosphate↗
PubMed1998

[Medical treatment of spinal cord injury in the acute stage].

OBJECTIVES: To evaluate the effect on neurologic outcome and the safety of nimodipine (N), methylprednisolone (M), or both (MN) versus no medical treatment (P) in spinal cord injury at the acute phase. STUDY DESIGN: Prospective, randomized clinical trial. PATIENTS: One hundred and six patients with a spinal trauma, including 48 with paraplegia and 58 with tetraplegia. METHOD: After eligibility, patients were randomly allocated in one of the following groups: M = methylprednisolone 30 mg.kg-1 over 1 hour, followed by 5.4 mg.kg-1.h-1 for 23 hours, N = nimodipine 0.015 mg.kg-1.h-1 over 2 hours followed by 0.03 mg.kg-1.h-1 for 7 days, MN or P. Neurologic assessment (ASIA score) was performed by a senior neurologist before treatment and at the 1-year follow-up. Early spinal decompression and stabilization was performed as soon as possible after injury. RESULTS: One hundred patients were reassessed at the 1-year follow-up. Neurologic improvement was seen in each group (P < 0.0001), however no neurologic benefit from treatment was observed. Infectious complications occurred more often in patients treated with M. Early surgery (49 patients), within the first 8 hours did not influence the neurologic outcome. The only predictor of the latter was the extent of the spinal injury (complete or incomplete lesion). CONCLUSION: Currently, no evidence of the benefit of medical treatment in this indication is existing. Because of the lack of clinical studies proving efficacy of pharmacological treatment in this specific pathology, a systematic use of medications cannot be recommended.

Acute Disease↗