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M Pineau

Publications and source records attributed to M Pineau.

8 recordsLinked to original sources

Intra-abdominal hypertension and abdominal compartment syndrome in burn patients.

BACKGROUND: Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are known to occur in patients after major abdominal surgery. The incidence of IAH and ACS in the burn population is not known. METHODS: We prospectively recorded the intra-abdominal pressures of major burn patients admitted to our burn center from February 1999 to September 1999. A bladder pressure greater than 25 mm Hg was diagnosed as IAH. ACS was diagnosed when pulmonary compliance decreased in association with persistent IAH and was treated with abdominal decompression. RESULTS: Ten patients were placed on the protocol; of these, seven developed IAH. Five responded to conservative treatment. Two patients with 80% body surface area burns developed ACS and required decompression. CONCLUSIONS: IAH occurs commonly in major burn patients, and ACS is seen regularly in patients with more than 70% body surface area burns. We recommend bladder pressure measurements after infusion of more than 0.25 L/kg during the acute resuscitation phase and for peak inspiratory pressures greater than 40 cm H2O. Whereas ACS warrants surgical decompression of the abdominal cavity, IAH usually responds to conservative therapy.

Adult↗

Global context effects on musical expectancy.

The effects of global harmonic contexts on expectancy formation were studied in a set of three experiments. Eight-chord sequences were presented to subjects. Expectations for the last chord were varied by manipulating the harmonic context created by the first six: in one context, the last chord was part of an authentic cadence (V-I), whereas in the other, it was a fourth harmonic degree following a full cadence (I-IV). Given this change in harmonic function, the last chord was assumed to be more expected in the former context, all the other local parameters being held constant. The effect of global context on expectancy formation was supported by the fact that subjects reported a lower degree of completion for sequences ending on an unexpected chord (Experiment 1), took longer to decide whether the last chord belonged to the sequence when the last chord was unexpected (Experiment 2), and took longer to decide whether the last chord was consonant or dissonant when it was unexpected (Experiment 3). These results are discussed with reference to current models of tonal cognition.

Auditory Perception↗

[Postoperative hypoglycemia after excision of pheochromocytoma. A case].

A case of hypoglycaemia consecutive to excision of a bilateral phaeochromocytoma in a 33-year old patient with Sipple's syndrome is reported. The severity of the hypoglycaemia (1.3 mmol/l) accounted for the brain lesions which ultimately resulted in the patient's death. Eight cases of hypoglycaemia occurring in similar circumstances have been published. The condition is due to the massive release of insulin during the hours that follow removal of the tumour. This results in the persistence of the peri-operative hyperglycaemic stimulation and in the suppression of the previous inhibition of insulin secretion due to alpha-adrenergic stimulation of catecholamines in the beta-cells of Langerhans' islets.

Adrenal Gland Neoplasms↗

The pharmacokinetics of lignocaine and beta-adrenoceptor antagonists in patients with acute myocardial infarction.

Lignocaine (lidocaine) and beta-adrenoceptor antagonists are widely used after acute myocardial infarction. The therapeutic value of these agents depends on the achievement and maintenance of safe and effective plasma concentrations. Lignocaine pharmacokinetics after acute myocardial infarction (MI) are controlled by a number of variables. The single most important is left ventricular function, which affects both volume of distribution and plasma clearance. Other major factors include bodyweight, age, hepatic function, the presence of obesity, and concomitant drug therapy. Lignocaine is extensively bound to alpha 1-acid glycoprotein, a plasma protein which is also an acute phase reactant. Increases in alpha 1-acid glycoprotein concentration occur after an acute MI, decreasing the free fraction of lignocaine in the plasma and consequently decreasing total plasma lignocaine clearance without altering the clearance of non-protein-bound lignocaine. Complex changes in lignocaine disposition occur with long term infusions, and therefore early discontinuation of lignocaine infusions (within 24 hours) should be undertaken whenever possible. Because the risk of ventricular tachyarrhythmia declines rapidly after the onset of an acute MI, lignocaine therapy can be rationally discontinued within 24 hours in most patients. Lignocaine has a narrow toxic/therapeutic index, so that pharmacokinetic factors are critical in dose selection. In contrast, beta-adrenoceptor antagonists' adverse effects are more related to the presence of predisposing conditions (such as asthma, heart failure, bradyarrhythmias, etc.) than to plasma concentration. The pharmacokinetics of beta-adrenoceptor antagonists are important to help assure therapeutic efficacy, to provide information about the anticipated time course of drug action, and to predict the possible role of ancillary drug effects (such as direct membrane action) and loss of cardioselectivity. Lipid solubility is the main determinant of the pharmacokinetic properties of a beta-adrenoceptor antagonist. Lipid-soluble agents like propranolol and metoprolol are well absorbed orally, and undergo rapid hepatic metabolism, with important presystemic clearance and a short plasma half-life. Water-soluble drugs like sotalol, atenolol, and nadolol are less well absorbed, and are eliminated more slowly by renal excretion. Clinical assessment of beta-adrenoceptor antagonism is more valuable than plasma concentration determinations in evaluating the adequacy of the dose of a particular beta-adrenoceptor antagonist.(ABSTRACT TRUNCATED AT 400 WORDS)

Adrenergic beta-Antagonists↗

Blood and urinary magnesium, zinc, calcium, free fatty acids, and catecholamines in type A and type B subjects.

Twenty type A male students were compared to nineteen type B male students (all in apparently good health), before and after exposure to combined stress (noise and task). Before stress, red blood cell (RBC) Zn concentration is higher (P less than .05) and Zn excretion lower (P less than .05) in type A than in type B people. After stress, type A subjects exhibit changes that are larger and more significant than those of type B individuals. After stress, the type A group shows an important increase of urinary catecholamines (P = 2.10(-5), serum free fatty acids, and urinary Zn (P = .001); a slight increase in plasma magnesium (P less than .05); and a small but significant decrease in RBC Mg (P less than .02). These results suggest that type A subjects are more sensitive to stress than are type B people and more readily lose their intracellular Mg, the rise in plasma Mg being a transient one, probably consecutive to the cellular loss. The present observations are in good agreement with published data: ie, the psychological characteristics of type A personalities; their greater susceptibility to ischemic heart disease, which has been associated with Mg deficiency; the possible role of hypomagnesemia in the pathogenesis of hypertension and coronary vasospasm; and the high RBC Zn levels found in hypertensive patients.

Adult↗

Role of H-2 and non-H-2 genes in the control of blood magnesium levels.

Red blood cell (RBC) and plasma (P) magnesium levels have been determined in 372 male mice of 13 inbred and H-2 congenic strains with C3H or B10 genetic backgrounds. Several groups of individuals belonging to the same strains have been tested at various times over a 2-year period to verify the results. Time and interstrain variations are highly significant for both RBC and P Mg. Statistical analyses made either with or without corrections for the time effect show that the largest variations are due to the genetic background (P less than 10(-10) ), the effect of the H-2 complex being smaller but nevertheless highly significant (P less than 10(-4) to 10(-6) ), except for the RBC Mg of the strains with B10 background. These findings can be compared with those previously obtained in man, and they demonstrate the high heritability of blood Mg concentration and its association with the major histocompatibility complex or with closely linked genes.

Animals↗

Abdominal compartment syndrome in patients with burns.

Abdominal compartment syndrome (ACS) is a well-recognized perioperative complication that occurs in patients who undergo intra-abdominal operations and who require extensive fluid resuscitation. The classic presentation of this syndrome includes high peak airway pressures; oliguria, despite adequate filling pressures; and intra-abdominal pressures of more than 25 mm Hg. A decompressive laparotomy performed at the bedside can alleviate ACS. If left untreated, sustained intra-abdominal hypertension is often fatal. In the literature, ACS has been described in pediatric patients with burns but not in adult patients with burns. This article describes 3 adults who sustained burns of more than 70% of their body surface areas, who required more than 20 L of crystalloid resuscitation, and who developed ACS during their resuscitation after the burn injury. The mortality rate among these patients was 100%, which confirms the grave consequences of this syndrome. In our institution, intra-abdominal pressure is now routinely measured as part of the burn resuscitation process in an attempt to diagnose and treat this syndrome earlier and more efficaciously. It is recommended that the possibility of ACS be considered when diagnosing any patient with burns who develops high airway pressures, oliguria, or both.

Abdomen↗