Biomedical subjects

M Malinge

Publications and source records attributed to M Malinge.

At least 19 recordsLinked to original sources

PubMed2005

[Anaesthesia and prostate surgery].

OBJECTIVES: To review the current data about anaesthetic management in prostate surgery with special regards on analysis and prevention of specific risks, appropriate anaesthetic procedure keeping with surgery and patient, recognition and treatment of adverse events. DATA SOURCES AND EXTRACTION: The Pubmed database was searched for articles (1990-2004) combined with references analysis of major articles on the field. DATA SYNTHESIS: It is strongly recommended to settle germfree urine in the preoperative period. The thromboembolic risk of radical retropubic prostatectomy for cancer parallels lower abdomen oncologic surgery and is prolonged. Preoperative evaluation of cardiovascular, respiratory, neurological and metabolic comorbidity is a source of prognostic information and an essential tool in the management of elderly patients with prostate disease. Extreme patient positioning applied in prostate surgery induces haemodynamic and respiratory changes and are associated with severe muscular and nervous injuries. The laparoscopic access for radical prostatectomy is a growing alternative to the open surgical procedure. Acute normovolaemic haemodilution is a consistent and cost-effective blood conservation strategy in reducing allogenic blood transfusion for radical retropubic prostatectomy. Whether open transvesical or transurethral prostatectomy for treatment of benign hypertrophy depends on the size of the gland: transurethral resection is safe up to 80 g. Intrathecal anaesthesia with a T9 cephalad spread of sensory block, produces adequate conditions for transurethral prostatectomy and allows a rapid diagnosis of irrigating fluid absorption syndrome. In spite of recommended preoperative antibiotic prophylaxis, bacteriemias are frequent during transurethral prostate resection.

Adenoma↗

PubMed2003

Sedation caused by clonidine in patients with spinal cord injury.

BACKGROUND: In patients with spinal cord injury, cephalad spread of intrathecal (i.t.) medication could be delayed. METHODS: We used bispectral index and an observer scale to assess sedation after two different doses of i.t. clonidine in patients with or without spinal cord injury. Twelve patients with neurological deficit caused by trauma (Spinal Cord Injury, SCI) were compared with patients without neurological disease. They received 10 mg of i.t. bupivacaine with clonidine, with either 50 microg (low dose, n=6) or 150 microg (high dose, n=6) at L(2)-L(3). A further 12 patients, six with spinal trauma lesion and six healthy, received i.t. bupivacaine and 150 micro g of i.m. clonidine. RESULTS: Sedation and a decrease in BIS occurred only in patients receiving 150 microg of clonidine. Onset of sedation and the decrease in BIS was delayed in most spinal cord injured patients whatever the route of administration (P<0.001). Duration of sedation was not different between the groups. Delayed sedation and decrease of BIS after i.t. clonidine in patients with spinal cord injury are similar than those observed after i.m. clonidine. CONCLUSION: A systemic effect is likely to be the main reason for sedation.

Adrenergic alpha-Agonists↗

PubMed2000

Intrathecal anesthesia: ropivacaine versus bupivacaine.

We compared intrathecal ropivacaine to bupivacaine in patients scheduled for transurethral resection of bladder or prostate. Doses of ropivacaine and bupivacaine were chosen according to a 3:2 ratio found to be equipotent in orthopedic surgery. One hundred patients were randomly assigned to blindly receive either 10 mg of isobaric bupivacaine (0.2%, n = 50) or 15 mg of isobaric ropivacaine (0.3%, n = 50) over 30 s through a 27-gauge Quincke needle at the L2-3 level in the sitting position. Onset and offset times for sensory and motor blockades and mean arterial blood pressure were recorded. Pain at surgical site requiring supplemental analgesics was recorded. Cephalad spread of sensory blocks was higher with bupivacaine (median level, cold T(4) and pinprick T(7)) than with ropivacaine (cold T(6) and pinprick T(9)) (P<0.001). Eight patients in Group Ropivacaine received IV alfentanil (P<0.01). Onset time (mean +/- SD) to T(10) anesthesia and offset time at L2 were not different (bupivacaine = 13 +/-8 min, 127+/-41 min; ropivacaine = 11+/-7 min, 105+/-29 min). Complete motor blockade occurred in 43 patients with bupivacaine and in 41 patients with ropivacaine (not significant). Total duration of motor blockade was not different. No difference in hemodynamic effects was detected between groups. No patient reported back pain. We conclude that 15 mg of intrathecal ropivacaine provided similar motor and hemodynamic effects but less potent anesthesia than 10 mg of bupivacaine for endoscopic urological surgery.

Aged↗

PubMed1999

Cholecystokinin receptor agonists block the jumping behaviour precipitated in morphine-dependent mice by naloxone.

The aim of present study was to reveal the role of cholecystokinin (CCK) in the jumping behaviour induced by the opioid antagonist naloxone (30 mg/kg) after the acute administration of morphine (200 mg/kg) in mice. Treatment with caerulein (0.01-1 microg/kg), a nonselective agonist of CCK receptors, induced a large reduction of jumping frequency without parallel suppression of locomotor activity. The CCK(B) receptor agonist CCK tetrapeptide (CCK-4. 0.125-32 mg/kg) caused the same effect, but it happened at much higher doses (above 0.5 mg/kg). Devazepide (1 microg/kg), a preferential CCK(A) receptor antagonist, completely reversed the action of caerulein (0.1 gmg/kg) and CCK-4 (2 mg/kg). A preferential CCK(B) receptor antagonists LY 288,513 at a high dose (4 mg/kg) blocked the action of CCK-4, but not that of caerulein. Acetorphan (16-128 mg/kg), an inhibitor of enkephalin metabolism, did not block naloxone-precipitated jumping behaviour. However, the combination of subthreshold doses of caerulein (0.001 microg/kg) and CCK-4 (0.25 mg/kg) with acetorphan (64 mg/kg) potently antagonized the behaviour induced by naloxone. In conclusion, the antagonism of CCK agonists against naloxone-precipitated jumping behaviour is apparently mediated via the CCK(A) receptor subtype. The stimulation of CCK(A) receptors seems to increase the release of endogenous enkephalins.

Animals↗

PubMed1999

Intrathecal bupivacaine in humans: influence of volume and baricity of solutions.

BACKGROUND: The effects of volume and baricity of spinal bupivacaine on block onset, height, duration, and hemodynamics were studied. METHODS: Ninety patients undergoing endoscopic urologic procedures were randomized to receive 10 mg of intrathecal bupivacaine at L2-L3 level in sitting position. In the operating room, commercial products were diluted as needed with NaCl 0.9% to obtain isobaric solutions (density, 1.005-1.008) or with NaC 10.9% and glucose 30% to obtain hyperbaric solutions (density, 1.031-1.037) of 2, 5, or 10 ml (six groups of 15 patients each). Three minutes after spinal injection the patients were placed in lithotomy position. Sensory blockade was assessed using pinprick and cold sensation tests, and motor blockade was assessed using a four-point scale. RESULTS: Onset times to maximal cephalad spread of spinal blockade were similar with isobaric and hyperbaric solutions. A greater maximal cephalad spread of anesthesia was obtained with diluted isobaric bupivacaine but was not associated with more hypotension. Volume had no effect on cephalad extent of anesthesia with hyperbaric bupivacaine. Times for regression of anesthesia to L2 and offset of motor block were longer with isobaric than with hyperbaric solutions of bupivacaine. The intensity of motor blockade was decreased with diluted hyperbaric bupivacaine. No patient reported back pain. CONCLUSION: In this study, volume had no significant influence on either cephalad spread or duration of sensory blockade for either isobaric or hyperbaric bupivacaine. Time for offset of anesthesia was shorter with hyperbaric bupivacaine compared with isobaric solutions.

Aged↗

PubMed1998

The urodynamic effects of intravenous opioids and ketoprofen in humans.

UNLABELLED: We used a double-blind design to study urodynamic changes induced by mu-agonists (fentanyl, morphine), a partial mu-agonist antagonist (buprenorphine), a putative mu-antagonist, kappa-agonist (nalbuphine), and ketoprofen, an injectable nonsteroidal antiinflammatory drug. Men (20-55 yr old) were randomly assigned to receive one of the following i.v. before anesthesia for endoscopic extraction of a ureteral stone: 10 mg of morphine, 0.3 mg of buprenorphine, 0.35 mg of fentanyl, 20 mg of nalbuphine, 100 mg of ketoprofen, or 10 mL of 0.9% sodium chloride. The urodynamic study consisted of cystometry followed by urethral pressure profile. Measurements were taken before the i.v. infusion of drugs and 15 min thereafter. Statistical comparisons were performed by using analysis of variance with repeated measurements (P < 0.05). Ketoprofen and saline did not induce any urodynamic changes. Opioids altered bladder sensations, and the residual volume after voiding increased, except after morphine. Detrusor contraction decreased only after the administration of fentanyl and buprenorphine. Some patients could not micturate after receiving morphine, fentanyl, and buprenorphine. Compliance and urethral pressures did not change with any drug. This study suggests that ketoprofen and nalbuphine are useful analgesics in terms of their urodynamics. IMPLICATIONS: We compared the urodynamic effects of opioids and ketoprofen used as analgesics in surgical patients. In contrast to ketoprofen, opioids altered urodynamics. The opioid nalbuphine had no effect on detrusor contraction. This study suggests that ketoprofen and nalbuphine are useful analgesics in terms of their urodynamics.

Adult↗

PubMed1996

A new design of trial for hypnotics comparison: a double-blind cross-over trial with patient's preference assessment and continuation of the preferred treatment.

1. This study compared two hypnotics administrated at comparable therapeutic dosages: triazolam (0.25 mg) and loprazolam (1 mg), were administered using an original scheme (cross-over on the first 2 nights, and continuation of the preferred treatment or new randomization). 2. Sixty-seven outpatients complaining of common insomnia participated in this study conducted by general practitioners. 3. Both drugs provided improvement in sleep quality (decreased sleep latency, increased total duration of sleep, decreased number of night awakenings), and are equally well tolerated. 4. For the first 2 nights, triazolam was evaluated to be more efficient than loprazolam (p < 0.001), and patients felt more rested the following day (p < 0.01) with the former drug. Moreover, triazolam is more frequently preferred than loprazolam by 47.7% and 29.2%, respectively, (p = 0.09). 5. No interaction was found between treatment and order of administration or specific effects and order of administration.

Adult↗

PubMed1996

Pharmacodynamic dose-response and safety study of cisatracurium (51W89) in adult surgical patients during N2O-O2-opioid anesthesia.

After administration of doses ranging from 0.025 to 0.25 mg/kg, the neuromuscular blocking effect of cisatracurium was assessed in 119 adult surgical patients receiving N2O-opioid-midazolam-thiopental anesthesia. The calculated 95% effective dose (ED95) for inhibition of adductor pollicis twitch evoked at 0.1 Hz was 0.053 mg/kg. With 0.10 mg/kg injected over 5-10 and 20-30 s, median onset times (range) were 5.8 (3.0-7.7) and 4.8 (1.2-10.2) min, respectively, and median times to 5% and 95% recovery (range) were 27 (19-46) and 48 (25-68) min, respectively. For doses of 0.10, 0.20, and 0.25 mg/kg, median 5%-95% and 25%-75% recovery indexes ranged from 48 to 90 min and 8 to 9 min, respectively. After administration of neostigmine (0.06 mg/kg) at 10%-15% or 16%-30% recovery, the median times to 95% recovery (range) were 6 (2-22) and 4 (2-5) min, respectively. There were no changes in heart rate, blood pressure, or plasma histamine concentrations during the first 5 min after administration of cisatracurium at doses up to 5 x ED95 injected over 5-10 s. No cutaneous flushing or bronchospasm was noted. In summary, cisatracurium is a potent neuromuscular blocking drug with an intermediate duration of action, characterized by excellent cardiovascular stability, with no apparent histamine release.

Adolescent↗

PubMed1996

Two faces of cholecystokinin: anxiety and schizophrenia.

It has been suggested that cholecystokinin (CCK), a gut-brain peptide found in high concentrations in the mammalian brain, might be implicated in the neurobiology of anxiety and panic disorder. The administration of CCK tetrapeptide induced panic attacks analogous to spontaneous ones in patients suffering from panic disorder and to a lesser degree in healthy volunteers. In animal models of anxiety, the pretreatment with CCK agonists and antagonists produced, respectively, anxiogenic- and anxiolytic-like action on the exploratory paradigms. On the other hand, CCK could also play a role in the pathophysiology of schizophrenia. The administration of CCK agonists (caerulein, CCK-8s) to rodents results in behavioural effects analogous to those of antipsychotic drugs. However, CCK agonists lack any activity in rodent behavioural models to reveal antipsychotic drugs. A significant reduction of CCK concentration and CCK receptors has been shown in cortical and limbic structures of patients suffering from schizophrenia. Nevertheless, administration of CCK agonists to these patients does not effect their symptoms. Two major conclusions should be drawn: first, CCK is involved in the neurobiology of anxiety; second, changes in the CCK system in schizophrenia could be linked to a cortical neurodegeneration related to this disease.

Animals↗

PubMed1995

Controlled comparison of the effects and abrupt discontinuation of buspirone and lorazepam.

1. The purpose of this study was to compare the effects and abrupt discontinuation of buspirone 15 or 20 mg tid and lorazepam 3 or 4 mg tid following 8 weeks of treatment. A total of 43 outpatients with generalized anxiety disorder were included in the study and 39 entered the withdrawal phase. 2. Clinical assessments were performed at baseline, 2, 4, 6 and 8 weeks (active phase) and after 9 and 10 weeks (withdrawal phase). These included the Hamilton anxiety scale, the visual analogue scale, the CHESS 84 (a check list for the evaluation of somatic symptoms) and the Lader tranquilizer withdrawal scale (translated in french). 3. Results show similar efficacy for lorazepam and buspirone during the active phase with a higher significant difference for buspirone on the CHESS 84 in relation with neurovegetatives symptoms: lorazepam D0 :16.30 +/- 3.14 D56: 5.10 +/- 0.93 (p < or = 0.01) buspirone D0 :18.82 +/- 3.4 D56: 4.73 +/- 1.18 (p < or = 0.001) No withdrawal phenomena was observed for both drugs using HAM-A lorazepam D63 :12.59 +/- 2.26 D70: 12.0 +/- 1.75 (p = ns) buspirone D63 :10.05 +/- 1.28 D70: 10.32 +/- 1.82 (p = ns) and the same significant difference using Lader scale: lorazepam D63 :4.44 +/- 0.89 D70: 6.96 +/- 1.28 (p < or = 0.05) buspirone D63 :2.95 +/- 0.66 D70: 4.15 +/- 0.92 (p < or = 0.05). 4. This study confirmed that buspirone was as effective as lorazepam at D56 in monitored outpatients with generalized anxiety disorder.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1995

[Experimental and clinical pharmacology of psychostimulants].

OBJECTIVE: To examine the fact that, after 50 years, the introduction of amphetamines for therapeutic purposes, psychostimulants such as methylphenidate have proved to be effective medications used in the treatment of childhood hyperactivity, yet misunderstood. METHOD: A review of the literature is undertaken on the use of psychostimulants in children and adults. RESULTS: Studies evaluating their helpfulness in adults are for the most part outdated and nonexploratory. CONCLUSION: their rehabilitation could prove to be useful for young and older adults, on condition that their target syndromes are studied more thoroughly.

Adult↗

PubMed1991

Clonidine as a sensitizing agent in the forced swimming test for revealing antidepressant activity.

The forced swimming test (FST) in mice has failed to predict antidepressant activity for drugs having beta adrenoreceptor agonist activity and for serotonin uptake inhibitors. We investigated the potential for clonidine to render the FST sensitive to antidepressants by using a behaviorally inactive dose of this agent (0.1 mg/kg). All antidepressants studied (tricyclics, 5-HT uptake inhibitors, iprindole, mianserin, viloxazine, trazodone) showed either activity at lower doses or activity at previously inactive doses. The effect appeared specific because it did not appear with drugs other than antidepressants (diazepam, chlorpromazine, sulpiride, atropine), except for amphetamine and apomorphine which have a strong effect on the dopaminergic system. The use of behaviorally subactive doses of clonidine may thus provide an important means of increasing the sensitivity of the forced swimming test.

Animals↗

PubMed1988

Additive effects of clonidine and antidepressant drugs in the mouse forced-swimming test.

In the mouse forced-swimming model, dose-dependent reversal of immobility was induced by the alpha-agonist clonidine given IP 30 min before testing. In addition, three preferential inhibitors of 5-HT uptake (citalopram, indalpine and fluvoxamine) had similar activity in the dose range 8-16 mg/kg as did the 5-HT1 agonist 8-OH-DPAT (1-4 mg/kg). Pretreatment with alpha-methyl-paratyrosine (100 mg/kg) did not prevent clonidine (1 mg/kg) action, suggesting that there was mediation by alpha post-junctional receptors. The effect of clonidine was unaltered by prazosin (2 mg/kg) and reversed by yohimbine (4 mg/kg) and 5-MeODMT (1 mg/kg), whereas it was potentiated by reserpine (2.5 mg/kg), methysergide (2 mg/kg) and ketanserin (8 mg/kg). Moreover, an ineffective dose of clonidine (0.06 mg/kg at 45 min pre-testing) made active subthreshold doses of various antidepressants (given at 30 min pre-testing): imipramine (4 mg/kg), amitriptyline (1 mg/kg), maprotiline (8 mg/kg), citalopram (2 mg/kg), indalpine, fluvoxamine and mianserin (4 mg/kg), viloxazine (2 mg/kg). Similar interactions were found with iprindole and nialamide (32 mg/kg), which were inactive alone up to 64 mg/kg, and 8-OH-DPAT (0.5 mg/kg) but not with major and minor tranquillizers. It is suggested that one effect of antidepressants might be the triggering of different relationships between alpha-2 and 5-HT mechanisms.

Animals↗

PubMed1988

Influence of alpha stimulants and beta blockers on yohimbine toxicity.

1. Potentiation of yohimbine-induced sublethality has been largely used to predict antidepressant action. 2. Several products were tested in order to understand the mechanism of this toxicity better: an alpha-1 central stimulant (adrafinil); an alpha-2 central stimulant (clonidine); and 4 beta-blockers (propranolol, atenolol, penbutolol and metoprolol). 3. It was found that atenolol and adrafinil could not antagonize toxicity, whereas clonidine and the other 3 beta-blockers could. 4. It is suggested that a central beta-origin toxicity exists since only beta-blockers which cross the blood-brain barrier are capable of antagonizing this activity. 5. The fact that clonidine also antagonized this toxicity may be explained by the beta-antagonist action of this substance at the high doses used.

Adrenergic alpha-Agonists↗

PubMed1987

[Halogenated inhalation anesthesia with a semiclosed circle system].

Thirty-six patients were anaesthetized for a maxillofacial surgical procedure. Ventilation was controlled by a ventilator (Kontron ABT 4100) with a semi-closed circle system. The flow of fresh gases was 1,200 ml.min-1. The vaporizer for the halogenated anaesthetic agent was placed out of the circle before the ventilator. Halothane was used for maintenance of anaesthesia and isoflurane for induced hypotension in orthognathic surgery. The inspired concentration of the halogenated agent was monitored by an analyser. A linear correlation between the delivered and the inhaled concentration of halogenated agent was established, the latter never reaching the delivered concentration. Monitoring the inspired oxygen concentration was required, so as to maintain a constant value. Carbon dioxide absorption by soda lime was also studied. The known advantages were: substantial economies in nitrous oxide and halogenated agents, prevention of contamination of the operating theatre, humidification and warning of the inspired gases. The use of such a system with the vaporizer out of the circle was safe, all the more so as the concentration of inhaled halogenated agents could be predicted.

Adult↗

PubMed1987

[Curarization of the myasthenia patient by atracurium].

The use of atracurium, a new intermediate duration of action non depolarizing muscle relaxant, is described in a myasthenic patient undergoing abdominal surgery. The effective dose to 95% twitch suppression is 0.15 mg.kg-1. Following the first dose, the time from maximum twitch depression to 25% recovery is 32 min, and 33 min following the second dose. The recovery index (25-75% recovery time) and the 5-90% recovery time are respectively 33 and 83 min. The train-of-four ratio is greater than 0.7 within 90 min after the reinjection. The significance of the behaviour of atracurium is discussed. In reduced dosage and with careful neuromuscular monitoring, atracurium appears to be a reasonable and safe choice of myasthenic patients to provide surgical relaxation.

Aged↗

PubMed1987

Vecuronium and atracurium in patients with end-stage renal failure. A comparative study.

Twenty patients with end-stage renal failure, undergoing kidney transplantation, were assigned randomly to receive either vecuronium or atracurium under evoked twitch tension control. The cumulative-dose technique was used to obtain 95% twitch depression (vecuronium: initial bolus 15 micrograms kg-1, increments 6 micrograms kg-1; atracurium: initial bolus 100 micrograms kg-1, increments 40 micrograms kg-1). Using ED95 values derived from the log-probit dose-response curves, vecuronium was 4.6 times more potent than atracurium. The durations of action of the initial cumulative-doses (from end of injection of the last increment to 25% recovery) were 11.1 +/- 3.3 min for vecuronium and 16.2 +/- 3.9 min for atracurium (P less than 0.05). In terms of duration of action of the maintenance doses (vecuronium one-quarter of the total incremental dose; atracurium one-third) some cumulation was observed with vecuronium (interaction time X treatment; cumulation ratio 1.46 +/- 0.31 v. 0.98 +/- 0.10 for atracurium, P less than 0.001). After 2 h of surgery, the mean recovery times (25% to 75% twitch height) did not differ (18.5 +/- 2.8 min and 16.7 +/- 4.4 min). It is concluded that vecuronium might be less safe than atracurium in patients with end-stage renal failure undergoing prolonged operations.

Adult↗

PubMed1981

[Gas gangrene of dental origin. Report on four cases (author's transl)].

Four patients developed diffuse cervicofacial cellulitis following an acute circumscribed infection of dental origin. Necrosis of skin, subcutaneous and muscle layers was associated with a severe generalised toxic infective syndrome, producing a clinical picture and following a course identical with that observed in gas gangrene of the limbs. Anaerobic germs, normally present in the buccodental region, were at the origin of the affection in all four cases, chronic dental lesions providing favourable anaerobic conditions for an increase in their virulence. Three factors appear to be of importance for the development of gas gangrene from dental abscesses: insufficient or lack of suitable surgical treatment, the use of antibiotics not active against anaerobic germs, treatment with corticoids or anti-inflammatory drugs. Once gas gangrene has developed, possible intramediastinal spread should be investigated. Treatment is essentially surgical (with excision of necrotic tissue and wide drainage), plus penicillin therapy and hyperbaric oxygen. The prophylaxis of these gas gangrene lesions is discussed.

Adult↗