Biomedical subjects

G Audibert

Publications and source records attributed to G Audibert.

At least 19 recordsLinked to original sources

PubMed2001

Relevance of diffusion and perfusion weighted mri for endovascular treatment of vasospasm in subarachnoid hemorrhage.

The endovascular treatment of vasospasm is effective when implemented rapidly. However its indication often proves difficult on account of the lack of diagnostic arguments or the difficulties in obtaining them in daily practice. We report a case that highlights the relevance of MRI in the decision-making process. A 37-year-old patient presented with symptomatic vasospasm of the middle cerebral artery and was subjected to morphological, diffusion- and perfusion-weighted MRI. These investigations confirmed the presence of significant oligemia in the MCA territory and revealed onsetting diffusion disorders. Angioplasty was immediately performed, resulting in normal diffusion and hemodynamic parameters and complete regression of clinical signs. This case highlights the relevance of MRI when assessing vasospasm before treatment. Coupled with transcranial Doppler, it should help teams quickly select patients most likely to benefit from angioplasty.

Adult↗

PubMed2000

Evaluation of donor cardiac function for heart transplantation: experience of a French academic hospital.

OBJECTIVES: The diagnostic and therapeutic approaches for evaluation and management of cardiac function in brain-dead patients vary from country to country. The aim of the present study was to describe the results of the evaluation of brain-dead patients as potential cardiac donors in a French teaching hospital that manages the largest number of brain-dead patients in France. METHODS: Demographic parameters, the causes of brain death, clinical evolution, hemodynamic parameters, doses of inotropic and/or vasopressive drugs, the results of echocardiographic examination, and several biochemical markers of myocardial cell injury were retrospectively collected. RESULTS: Seventy-one consecutive brain-dead patients admitted to the intensive care unit of the Academic Hospital of Nancy from October 1st, 1998 to September 30, 1999 were analyzed. Twenty-nine patients were considered as potential heart donors: 22 males and 7 females aged 33 +/- 3 years (Mean + SEM). The cause of brain death was head trauma in 17 cases (59%), cerebrovascular disease in 10 cases (34%), and cerebral anoxia related to cardiac arrest in 2 cases (7%). Eighteen hearts (18/29 or 66%) were harvested and transplanted with a favorable outcome at one month in 17 cases. In 11 cases, the heart was not harvested, nine (9/29 or 31%) because of myocardial dysfunction upon subsequent echocardiographic examination and 2 because of the lack of matched recipients. CONCLUSION: Comparison of these results with those of other groups suggests that hormonal substitution with insulin and triiodothyronine in the presence of myocardial dysfunction could be of potential interest to correct myocardial dysfunction and increase the number of donor hearts.

Academic Medical Centers↗

PubMed1999

Multivariate analysis of predictors of cerebral vasospasm occurrence after aneurysmal subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: The role of type of treatment on cerebral vasospasm occurrence after aneurysmal subarachnoid hemorrhage (SAH) has not been studied. Through multivariate analysis we determined the independent prognostic factors of the occurrence of symptomatic vasospasm following aneurysmal SAH in a study cohort of 244 patients undergoing either surgical or endovascular treatment. The prognostic factors of sequelae after aneurysmal SAH were studied as well. METHODS: Symptomatic vasospasm was defined as the association of deterioration in a patient's neurological condition between 3 and 14 days after SAH with no other explanation and an increase in mean transcranial Doppler velocities of >120 cm/s. The prognostic factors were registered on admission and during the intensive care stay. RESULTS: Symptomatic vasospasm occurred in 22.2% surgical patients compared with 17.2% endovascular treatment patients (P=0.37). Multivariate analysis revealed that the probability of occurrence of symptomatic vasospasm decreased with age >50 years (relative risk [RR], 0.47 [0.25 to 0.88]) and severe World Federation of Neurological Surgeons (WFNS) grade measured on admission (RR, 0.43 [0.20 to 0.90]) and increased with hyperglycemia occurring during the intensive care stay (RR, 1.94 [1.04 to 3.63]). No difference in risk of symptomatic vasospasm could be identified between surgical and endovascular treatment. Symptomatic vasospasm (OR, 4.73 [CI, 1. 77 to 12.6]) as well as WFNS grade of >2 (OR, 8.95 [3.46 to 23.2]), treatment complications (OR, 8.39 [3.16 to 22.3]), and secondary brain insults were associated with an increased risk of 6-month sequelae. CONCLUSIONS: Age <50 years, good neurological grade, and hyperglycemia were all associated with an increased risk of cerebral vasospasm whereas treatment was not. This provides a basis for future clinical prospective randomized trials comparing both treatments.

Adult↗

PubMed1999

[Endovascular treatment of vasospasm].

Cerebral vasospasm remains a leading cause of heightened morbidity and mortality rates following aneurysmal subarachnoid hemorrhage despite the apparent benefit of recent medical therapeutics. Successful resolution of medically refractory angiographically demonstrated vasospasm with concomitant reversal of delayed neurological deficit has been observed after balloon angioplasty. Subsequent reports confirmed these encouraging results but also emphasized the limitations of the technique and the risks of complications. Intraarterial papaverine infusion has been performed for the treatment of diffuse cerebral vasospasm with controversial results and has also been combined with angioplasty either to facilitate balloon navigation or to treat arteries inaccessible to balloon catheterization. All these different endovascular approaches explain the confusion existing about the indications, timing and efficacy of the endovascular treatments. This article reviews several clinical and experimental studies dealing with these questions.

Angioplasty, Balloon↗

PubMed1998

Effect of the H1 blocker d-chlorpheniramine on cerebral blood flow in the conscious dog during normocapnic hypoxia.

The mechanism causing cerebral vasodilatation during hypoxia remains unclear. A role for histamine is suspected because H2 receptor-blocking drugs blunt the hypoxia-induced increase in cerebral blood flow (CBF). Moreover, in vitro blockade of H1 receptors by chlorpheniramine decreases the vasodilatation of cerebral arteries that is induced by histamine. The present study tested the hypothesis that an H1 receptor blocker (d-chlorpheniramine) would have a similar effect in vivo during hypoxia. Isocapnic hypoxia (inspired oxygen fraction, FIO2 = 0.10; inspired carbon dioxide fraction, FICO2 = 0.035) was induced in 16 conscious dogs randomly divided into two groups: eight dogs received saline intravenously (controls) at time 0 (normoxia) and after 2 h and 4 h hypoxia, and the other eight dogs received d-chlorpheniramine intravenously (0.5 mg kg-1) to block the H1 receptors. Regional CBF was measured by the radioactive microspheres technique 15 min after each injection of d-chlorpheniramine or saline. In the control group, CBF increased during hypoxia in all regions of the brain. In the d-chlorpheniramine group, total CBF increased similarly after 2 h of hypoxia. After 4 h of hypoxia, the increase was limited, especially in the pons, cerebral peduncles, hippocampus, hypothalamus, thalamus, and occipital lobes (six out of 12 studied regions). It is concluded that the H1 blocker d-chlorpheniramine did not strongly inhibit the increase in CBF during hypoxia. After cumulative doses, however, as in the fourth hour of hypoxia, the increase in total CBF was limited.

Animals↗

PubMed1998

Reversal of late septic shock with supraphysiologic doses of hydrocortisone.

OBJECTIVES: Preliminary studies have suggested that low doses of corticosteroids might rapidly improve hemodynamics in late septic shock treated with catecholamines. We examined the effect of hydrocortisone on shock reversal, hemodynamics, and survival in this particular setting. DESIGN: Prospective, randomized, double-blind, placebo-controlled study. SETTING: Two intensive care units of a University hospital. PATIENTS: Forty-one patients with septic shock requiring catecholamine for >48 hrs. INTERVENTIONS: Patients were randomly assigned either hydrocortisone (100 mg i.v. three times daily for 5 days) or matching placebo. MEASUREMENTS AND MAIN RESULTS: Reversal of shock was defined by a stable systolic arterial pressure (>90 mm Hg) for > or =24 hrs without catecholamine or fluid infusion. Of the 22 hydrocortisone-treated patients and 19 placebo-treated patients, 15 (68%) and 4 (21%) achieved 7-day shock reversal, respectively, a difference of 47% (95% confidence interval 17% to 77%; p = .007). Serial invasive hemodynamic measurements for 5 days did not show significant differences between both groups. At 28-day follow-up, reversal of shock was higher in the hydrocortisone group (p = .005). Crude 28-day mortality was 7 (32%) of 22 treated patients and 12 (63%) of 19 placebo patients, a difference of 31% (95% confidence interval 1% to 61%; p = .091). Shock reversal within 7 days after the onset of corticosteroid therapy was a very strong predictor of survival. There were no significant differences in outcome in responders and nonresponders to a short corticotropin test. The respective rates of gastrointestinal bleeding and secondary infections did not differ between both groups. CONCLUSIONS: Administration of modest doses of hydrocortisone in the setting of pressor-dependent septic shock for a mean of >96 hrs resulted in a significant improvement in hemodynamics and a beneficial effect on survival. These beneficial effects do not appear related to adrenocortical insufficiency.

APACHE↗

PubMed1997

Comparison of norepinephrine and dobutamine to epinephrine for hemodynamics, lactate metabolism, and gastric tonometric variables in septic shock: a prospective, randomized study.

OBJECTIVES: To compare the effects of norepinephrine and dobutamine to epinephrine on hemodynamics, lactate metabolism, and gastric tonometric variables in hyperdynamic dopamine-resistant septic shock. DESIGN: A prospective, intervention, randomized clinical trial. SETTING: Adult medical/surgical intensive care unit in a university hospital. PATIENTS: 30 patients with a cardiac index (CI) > 3.51 x min(-1) x m(-2) and a mean arterial pressure (MAP) < or = 60 mmHg after volume loading and dopamine 20 microg/kg per min and either oliguria or hyperlactatemia. INTERVENTIONS: Patients were randomized to receive an infusion of either norepinephrine-dobutamine or epinephrine titrated to obtain an MAP greater than 80 mmHg with a stable or increased CI. MEASUREMENTS AND MAIN RESULTS: Baseline measurements included: hemodynamic and tonometric parameters, arterial and mixed venous gases, and lactate and pyruvate blood levels. These measurements were repeated after 1, 6, 12, and 24 h. All the patients fulfilled the therapeutic goals. No statistical difference was found between epinephrine and norepinephrine-dobutamine for systemic hemodynamic measurements. Considering metabolic and tonometric measurements and compared to baseline values, after 6 h, epinephrine infusion was associated with an increase in lactate levels (from 3.1 +/- 1.5 to 5.9 +/- 1.0 mmol/l;p < 0.01), while lactate levels decreased in the norepinephrine-dobutamine group (from 3.1 +/- 1.5 to 2.7 +/- 1.0 mmol/l). The lactate/pyruvate ratio increased in the epinephrine group (from 15.5 +/- 5.4 to 21 +/- 5.8; p < 0.01) and did not change in the norepinephrine-dobutamine group (13.8 +/- 5 to 14 +/- 5.0). Gastric mucosal pH (pHi) decreased (from 7.29 +/- 0.11 to 7.16 +/- 0.07; p < 0.01) and the partial pressure of carbon dioxide (PCO2) gap (tonometer PCO2-arterial PCO2) increased (from 10 +/- 2.7 to 14 +/- 2.7 mmHg; p < 0.01) in the epinephrine group. In the norepinephrine-dobutamine group pHi (from 7.30 +/- 0.11 to 7.35 +/- 0.07) and the PCO2 gap (from 10 +/- 3.0 to 4 +/- 2.0 mmHg) were normalized within 6 h (p < 0.01). The decrease in pHi and the increase in the lactate/pyruvate ratio in the epinephrine group was transient, since it returned to normal within 24 h. CONCLUSIONS: Considering the global hemodynamic effects, epinephrine is as effective as norepinephrine-dobutamine. Nevertheless, gastric mucosal acidosis and global metabolic changes observed in epinephrine-treated patients are consistent with a markedly inadequate, although transient, splanchnic oxygen utilization. The metabolic and splanchnic effects of the combination of norepinephrine and dobutamine in hyperdynamic dopamine-resistant septic shock appeared to be more predictable and more appropriate to the current goals of septic shock therapy than those of epinephrine alone.

Adrenergic beta-Antagonists↗

PubMed1997

Is endotoxin and cytokine release related to a decrease in gastric intramucosal pH after hemorrhagic shock?

OBJECTIVES: (a) To investigate the relationship between gut ischemia parameters (gastric intramucosal pH [pHi], mucosal-arterial carbon dioxide difference [PCO2-gap]), and endotoxin or cytokine release during hemorrhagic shock; (b) to compare the predictive value of pHi, PCO2-gap and arterial lactate concentrations. DESIGN: Prospective study. SETTING: Surgical intensive care unit of a university hospital. PATIENTS: 20 multiple trauma patients with severe hemorrhagic shock. INTERVENTIONS: Intramucosal measurements and blood samples were obtained on admission to the emergency room and repeatedly over 48 h. MEASUREMENTS AND RESULTS: Endotoxin was measured using a chromogenic limulus amoebocyte assay. Cytokine [tumor necrosis factor-alpha (TNF alpha) and interleukin-6 (IL-6)] values were evaluated by immunoradiometric assays. Only 3 patients had positive blood cultures but endotoxins were detected at least once in all patients. Endotoxin levels were similar in survivors and non-survivors over the study period and were not related to pHi or PCO2-gap. Initially, high levels of IL-6 were observed in both nonsurvivors and survivors [median 1778 pg/ml (range 435-44,540) vs 2068 pg/ml (range 996-92,300)]. IL-6 levels progressively decreased in the survivors but not significantly. On admission, TNF alpha concentrations were similar in nonsurvivors and survivors (42 +/- 35 vs 46 +/- 27 pg/ml). From the 24th h, TNF alpha values were higher in the nonsurvivors than in the survivors (24 h: 72 +/- 38 vs 34 +/- 17 pg/ml, p < 0.05). The greatest IL-6 levels were found for a pHi < 7.20 (28.5 +/- 36.5 vs 1.8 +/- 1.3 ng/ml, p < 0.05) or a PCO2-gap > 7.5 mmHg (1 kPa) (32.5 +/- 37.5 vs 1.7 +/- 1.3 ng/ml, p < 0.01). With the same pHi threshold, no difference was found in endotoxin levels. The lactate concentrations were predictive for outcome from the 12th h (9.5 +/- 5.9 vs 3.6 +/- 2.3 mmol/l, p < 0.05). CONCLUSIONS: During severe hemorrhagic shock, endotoxin translocation from the gut was a common phenomenon that seemed independent of both pHi values and outcome. It could not explain IL-6 and TNF alpha release. In severe hemorrhagic shock, neither pHi nor PCO2-gap provides additional information to the lactate measurements.

Adult↗

PubMed1997

Intravenous angiography in brain death: report of 140 patients.

We present our experience and discuss the value of cerebral intravenous digital subtraction angiography (IV DSA) in the diagnosis of brain death. A total of 140 patients presenting with clinical signs of brain death were studied by IV DSA. According to the angiographic appearance of the vertebrobasilar system, the patients were divided into four groups. Cessation of blood flow within the internal carotid arteries and their branches was consistently found. Attention is focused on 9 patients with persistent blood flow within the posterior fossa. In sedated patients in whom EEG and evoked brain-stem responses are non-diagnostic, or in order to shorten the observation time, transcranial Doppler should be performed to determine the appropriate moment for IV DSA, which is a reliable method of confirming brain death.

Adolescent↗

PubMed1997

Pharmacokinetic-pharmacodynamic modeling of doxacurium: effect of input rate.

One of the basic assumptions in pharmacokinetic-pharmacodynamic modeling (PK-PD) is that drug equilibration rate constant between plasma concentration and effect (Ke0) is not changed by input rate. To test this assumption in a clinical setting, a 25 micrograms/kg i.v. dose of doxacurium was administered either by bolus injection or 10-min infusion to 15 anesthetized patients. Neuro-muscular function was monitored using train-of-four stimulation of the ulnar nerve. For the short infusion dose, arterial concentrations were measured at I-min intervals during infusion and at frequent intervals thereafter. Following the iv bolus dose, the early PK profile of doxacurium was investigated by measuring doxacurium arterial concentrations every 10 sec during the first 2 min and at frequent intervals thereafter. PK-PD modeling was performed using nonparametric approach with and without including a finite receptor concentration (Rtot) in the effect compartment. Kinetic parameters were unchanged. For the bolus and the infusion, Ke0 values were 0.053 +/- 0.006 and 0.056 +/- 0.009 min-1, respectively. Using the Rtot model, corresponding Ke0 values were 0.148 +/- 0.016 and 0.150 +/- 0.024, respectively. The relatively faster Ke0 obtained with the Rtot model is compatible with the high potency of doxacurium. Our results show that PK-PD parameters derived with either a bolus or an infusion mode of administration are equally reliable.

Adult↗

PubMed1997

Differential quantitative blood cultures in the diagnosis of catheter-related sepsis in intensive care units.

The aim of this prospective study was to compare differential blood cultures and quantitative catheter tip cultures for the diagnosis of catheter-related sepsis. Over a period of 2 years, 283 central venous catheters were inserted in 190 adult patients. Catheters were removed when they were no longer needed or when infection was suspected. Immediately before removal of the central venous catheters, blood cultures were performed, with blood drawn simultaneously from the catheter and the peripheral vein. After removal, quantitative catheter culture was performed according to the Brun-Buisson modified Cleri technique. Fifty-five quantitative catheter cultures were positive. They were classified as contaminated (n = 18), colonized (n = 23), or infected (n = 14). Differential blood cultures correctly identified 13 infections. With a catheter/peripheral cfu ratio of 8, differential blood cultures had a sensitivity of 92.8% and a specificity of 98.8%. When the catheters were removed because of suspected infection, differential blood cultures had a sensitivity of 92.8% and a specificity of 100%. Differential blood culture, a technique that does not necessitate catheter removal, seems effective in the diagnosis of catheter-related sepsis in patients in the intensive care unit.

Adult↗

PubMed1996

[Chylothorax following closed thoracic injury].

Chylothorax following blunt chest trauma is a rare event. The presence of a cloudy or milky persistent pleural effusion should suggest the possibility of its chylous origin. The diagnosis is made by analysis of the fluid obtained either from thoracentesis or tube thoracostomy. A lymphangiogram can show the site of the lesion, but computed tomography is a more recent and probably as helpful diagnostic test. An efficient control of the chylous effusion may be facilitated by using a fat-poor enteral nutrition and parenteral nutrition, which prevents malnutrition. Surgical ligation of the thoracic duct is relatively simple and efficient. It is indicated when the daily chylous flow is over 500 mL after 2 or 3 weeks of medical treatment or in case of weight loss.

Adult↗

PubMed1996

[Anesthesia and intensive care of subarachnoid hemorrhage. A survey on practice in 32 centres].

OBJECTIVE: To assess the current practices in anaesthesia and intensive care in patients experiencing subarachnoid haemorrhage (SAH). STUDY DESIGN: Analysis of questionnaire sent to the members of the French speaking Association of neuroanesthesia and intensive care. METHODS: The survey, performed in the summer of 1995, included questions on the composition of the neuroanesthesia team, anaesthesia, as well as medical and surgical treatments. RESULTS: Twenty-nine French and three non French centers answered the questionnaire. In 14 centers, more than 60 SAH had been treated in the previous year. Angiography was performed under sedation with a benzodiazepine associated with an opioid (54%). Criteria for choosing an endovascular approach were the site of the aneurysm (81%), its neck size (42%) and the underlying disease (42%). Anaesthesia was induced with either propofol (60%) or thiopentone (40%) associated with an opioid and a muscle relaxant. It was maintained with either isoflurane (59%) or propofol (41%). Nitrous oxide was often associated (62%). During anaesthesia, nimodipine (84%), mannitol (69%), anticonvulsants (47%), dopamine (31%) and lidocaine (9%) were also administered. Postoperatively, nimodipine was administered for prophylaxis of vasospasm (97%) and transcranial Doppler was employed to diagnose vasospasm (50%). Other techniques of care included hypervolaemia (89%), controlled arterial hypertension (36%) and haemodilution (36%).

Anesthesia, General↗

PubMed1996

[Subarachnoid hemorrhage caused by aneurysm rupture. Surgery or embolization?].

Traditionally the aneurysms of the circle of Willis have been an indication for neurosurgery. New technologies of endovascular treatment with electrically detachable coils resulted in a different therapeutical concept since four years. A series including 140 patients has been treated in our institution from 1 January 1992 to 31 December 1994, 94 of them presenting with a subarachnoid haemorrhage. Out of these 140 patients, 84 were treated with surgery, 51 with the endovascular technique, five with surgery after incomplete or unsuccessful endovascular treatment. Surgery was indicated in patients presenting early after bleeding, devoid of vasospasm, with a favourable Hunt and Hess grading and in aneurysms located in the anterior part of the circle of Willis. Endovascular treatment was indicated in patients admitted with delay, with severe vasospasm, a poor Hunt and Hess grading and in all aneurysms of the vertebrobasilar arterial network. Age was of less importance in comparison to the status of the vessels for selection of the method of treatment. Giant aneurysms are difficult to treat as surgery is faced with the size of the aneurysmal itself and endovascular technique with the width of the aneurysmal neck.

Aneurysm, Ruptured↗

PubMed1996

[Endovascular treatment of intracranial aneurysms].

Major improvements have been achieved in endovascular treatment of intracranial aneurysms during the last twenty years. Initial techniques of selective balloon occlusion were progressively replaced by the packing of the aneurysmal pouch with very small and soft metallic devices, named coils, with controlled detachment. In some rare cases, balloon occlusion is still used in order to occlude the parent vessel or to reverse the flow, especially in the vertebro-basilar system. Essential aims for the anaesthesiologist include: complete immobility of the patient throughout the endovascular procedure, systemic anticoagulation in order to avoid any thromboembolic complication during and after treatment, prevention and/or treatment of vasospasm, precise evaluation of fluid balance during the procedure. Our experience is based on 145 aneurysms in 135 patients, treated by endovascular route; 91 (63%) of them were revealed by a subarachnoid haemorrhage (SAH). Their main locations were: the carotid siphon (33.1%), the anterior communicating artery (19.3%), the basilar artery (17.2%) and the middle cerebral artery (17.2%). Thirty-seven of these aneurysms (25.5%) were very small in size with a diameter less than 4 mm. Total or sub-total (more than 90%) occlusion was achieved in 141 aneurysms (90.3%). Thromboembolic complications occurred in eight patients (5.9%), neurological sequelae in one. Other treatment-related complications included the migration of a coil outside the aneurysm in six cases (4.4%) without neurological deficit in one and five ruptures of the aneurysm (3.7%) during the procedure with one lethal issue due to the spontaneous bleeding of a controlateral arterio-venous malformation. Thirteen patients died (9.6%). The cause of the death was related on the initial SAH in 11 of them. The two others were both due to rupture: of a second untreated aneurysm in one case and of an associated arteriovenous malformation in the second one. At present the main indications of endovascular treatment are poor or non indications for neurosurgery. Due to the quality of results, endovascular therapy will be more and more used in case of ruptured or non ruptured aneurysms.

Cerebral Angiography↗

PubMed1996

[Treatment of post-traumatic acute anemia by recombinant human erythropoietin in Jehovah's Witnesses].

A 20-year-old Jehovah's witness patient experienced a femur fracture, with a section of the femoral artery and vein. On admission, haemoglobin concentration was 5.6 g.dL-1 and haematocrit 17%. Because of aponevrotomy, blood losses persisted. As the patient refused blood transfusion, recombinant human erythropoietin and parenteral iron were administered, associated with mild hypothermia, sedation and mechanical ventilation. After 21 days, the haemoglobin concentration increased to 10.9 g.dL-1 and haematocrit to 33% Recombinant human erythropoietin and parenteral iron may provide an alternative safe and effective therapy in life-threatening anaemia when blood transfusions are not accepted by the patient.

Acute Disease↗

PubMed1996

The onset of rocuronium, but not of vecuronium or mivacurium, is modified by tourniquet inflation.

A previous investigation showed that inflation of a tourniquet did not interrupt onset of vecuronium neuromuscular block. To test the hypothesis that this effect depended on potency, twitch tension was measured in an arm with a tourniquet inflated during onset and compared with a control arm in 30 patients under fentanyl-thiopental-nitrous oxide-isoflurane anesthesia. Patients were randomly allocated to receive either vecuronium 0.1 mg/kg (n = 10), rocuronium 0.6 mg/kg (n = 10), or mivacurium 0.2 mg/kg (n = 10). The electromyographic response of the first dorsal interosseus to single twitch stimulation of the ulnar nerve every 10 s was recorded in both arms. When neuromuscular block was 20% (i.e., twitch tension was 80% of control), the tourniquet was inflated to a pressure of 300 mm Hg. It was deflated 5 min later. In the vecuronium and mivacurium groups, the tourniquet did not influence onset of block. In the rocuronium group, maximum neuromuscular block was (mean +/- SD) 79% +/- 10% in the tourniquet arm, compared with 96% +/- 4% in the perfused arm (P < 0.05). The maximum rate of onset was half that of the perfused arm. The difference in maximum neuromuscular block between arms was 17% +/- 7%, 5% +/- 5%, and 0% +/- 2% in the rocuronium, vecuronium, and mivacurium groups (P < 0.05). To explain that onset of block continues in spite of interruption of blood flow, drug molecules must gain access to the neuromuscular junction via routes other than the circulation. The results of this investigation are consistent with the hypothesis that there is redistribution of drug from extrajunctional to junctional areas during onset of action of muscle relaxants and this process is more important for the more potent drugs (vecuronium and mivacurium) than for rocuronium.

Adult↗

PubMed1995

[Outcome of the use of albumin and colloid plasma substitutes from 1989 to 1993 in a French University Hospital Center].

OBJECTIVES: To evaluate the use of plasma substitutes (albumin, gelatins, dextrans, starches) from 1989 to 1993 in a 3000-bed University hospital and to assess the impact of the 1989 consensus conference of the French speaking Society of Intensive Care Medicine on the choice of plasma substitutes for treatment of hypovolaemia. STUDY DESIGN: Retrospective study of a case series. METHODS: Data on the use of albumin and artificial plasma substitutes were obtained from Blood Bank and Pharmacy. RESULTS: Between 1989 and 1993, the total amount of administered plasma substitutes decreased by 20%, allowing a saving of 1.7 million FF. There was a 60% decrease in the use of gelatins and dextrans. The starches, introduced in 1991, became in 1993 the most used plasma substitute, with 37% of the total. The use of albumin showed only a 32% decrease and was still in 1993 the main source of expenditure for plasma substitutes, with 3.8 million FF and 80% of the total cost. The number of plasmapheresis increased by 15%, whereas the use of albumin for plasmapheresis, almost constant in absolute value, increased from 31% in 1989 to 45% in 1993 of the total expenses. There were large differences between the services regarding the use of albumin. Intensive care and surgical units represented 70% of the total (plasmapheresis excluded). In this group, the overall fall of use was 22%, some units obtaining a 93% decrease whereas other did not change in spite of constant admission numbers. Medical units decreased their albumin use by 53%. CONCLUSION: The decrease in the albumin use between 1989 and 1993 was not significant. The impact of the consensus conference, if any, was weak. A careful evaluation of the prescriptions would be necessary to improve the compliance of clinical practice with recommendations by the consensus conference.

Albumins↗