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C Mardirosoff

Publications and source records attributed to C Mardirosoff.

At least 19 recordsLinked to original sources

Posture-related distribution of hyperbaric bupivacaine in cerebro-spinal fluid is influenced by spinal needle characteristics.

BACKGROUND: No studies have evaluated the relationship between duration of time sitting and spinal needle type on the maximal spread of local anaesthetics. The few trials available have studied the influence of time spent sitting on the spread of anaesthesia without standardising spinal needle types, and have not found any effect. METHODS: In this randomised, blinded study, 60 patients scheduled for elective orthopaedic surgery of the lower limbs were divided into 4 groups. With the patient sitting erect, 15 mg hyperbaric bupivacaine were injected in a standard manner through a 24G Sprotte or a 27G Whitacre needle and patients were placed supine after 1 min (24G/1 group and 27G/1 group) or 4 min (24G/4 group and 27G/4 group). RESULTS: Time to achieve maximum block height after injection was similar in all groups. Block height levels were significantly lower at all time points for the 24G/4 group. Maximum block heights were Th4 in the 24G/1, 27G/1 and 27G/4 groups, and Th6 in the 24G/4 group (P<0.0001). CONCLUSION: In a standard spinal anaesthesia procedure, when different lengths of time spent sitting are compared, spinal needle characteristics influence the maximum spread of hyperbaric bupivacaine. However, within the limits of our study, a two-segment difference in block height is too small to consider using spinal needles as valuable tools to control block height during spinal anaesthesia in our daily practice.

Adult↗

Efficacy and harm of pharmacological prevention of acute mountain sickness: quantitative systematic review.

OBJECTIVE: To quantify efficacy and harm of pharmacological prevention of acute mountain sickness. DATA SOURCES: Systematic search (Medline, Embase, Cochrane Library, internet, bibliographies, authors) in any language, up to October 1999. STUDY SELECTION: Randomised placebo controlled trials. DATA EXTRACTION: Dichotomous data on efficacy and harm from 33 trials (523 subjects received 13 different interventions, 519 a placebo). DATA SYNTHESIS: At above 4000 m the mean incidence of acute mountain sickness with placebo was 67% (range 25% to 100%); incidence depended on the rate of ascent, but not on the altitude or the mode of ascent. Across all ascent rates, dexamethasone 8-16 mg prevented acute mountain sickness (relative risk 2.50 (95% confidence interval 1.71 to 3.66); number needed to treat (NNT) 2.8 (2.0 to 4.6)), without evidence of dose responsiveness. Acetazolamide 750 mg was also efficacious (2.18 (1.52 to 3.15); NNT 2.9 (2.0 to 5.2)), but 500 mg was not. In two trials, adverse reaction (including depression) occurred after dexamethasone was stopped abruptly (4.45 (1.08 to 18); NNT 3.7 (2.5 to 6.9)). With acetazolamide, paraesthesia (4.02 (1.71 to 9.43); NNT 3.0 (2.0 to 6.0)) and polyuria (4.24 (1.92 to 9.37); NNT 3.6 (2.5 to 6.2)) were reported. Data were sparse on nifedipine, frusemide (furosemide), dihydroxyaluminium-sodium, spironolactone, phenytoin, codeine, phenformin, antidiuretic hormone, and ginkgo biloba. CONCLUSIONS: At above 4000 m, with a high ascent rate, fewer than three subjects need to be treated with prophylactic dexamethasone 8-16 mg or acetazolamide 750 mg for one subject not to experience acute mountain sickness who would have done so had they all received a placebo. Acetazolamide 500 mg does not work.

Acetazolamide↗

Brain magnetic resonance imaging (MRI) and neurological changes after a single high altitude climb.

PURPOSE: Neurological impairment, mental dysfunction, and brain imaging changes caused by severe hypoxia have been described by several authors. However, the occurrence of transitory, long lasting, or permanent brain damage has been debated. Although climbing to 8000 m is reserved to a small number of climbers, there are hundreds of lowlanders spending relatively short holidays climbing peaks up to 6000 m in the Andes or in the Himalayas. They are usually not well acclimated and often suffer from acute mountain sickness (AMS). The aim of this study was to examine the effect of a single high altitude exposure on the changes in brain MRI and neuropsychological testing in climbers. METHODS: Brain MRI, medical history, and a battery of neuropsychological tests were obtained in eight male climbers between 31 and 48 yr of age a few days before and between 5 and 10 d after returning to sea level following ascent to altitudes of over 6000 m without oxygen. RESULTS: The mean AMS symptom score recorded at 5500 m was three in all climbers, headache being the predominant symptom. CONCLUSION: We did not observe the changes in brain imaging and in neuropsychological testing observed by other authors. The residual central nervous system impairment following return from high altitude was not observed in our study, and the good results in neuropsychological testing were well correlated with the unchanged brain MRI imaging.

Adult↗

A serious anaesthetic complication of a Lefort I osteotomy.

We report a case of surgical transsection of the nasoendotracheal tube during a Lefort I maxillary osteotomy, resulting in severe intra-operative ventilatory difficulties. The management of this problem and a brief review of the literature are presented.

Adolescent↗

Two doses of intrathecal sufentanil (2.5 and 5 microg) combined with bupivacaine and epinephrine for labor analgesia.

UNLABELLED: In this study, we evaluated the effect of two doses of intrathecal sufentanil combined with bupivacaine and epinephrine on the incidence of pruritus and on the duration and quality of analgesia. One hundred five parturients were enrolled in this randomized, double-blinded, placebo-controlled study. They received either intrathecal 1.25 mg bupivacaine and 25 microg epinephrine (control group); 1.25 mg bupivacaine, 25 microg epinephrine, and 2.5 microg sufentanil (2.5-microg group); or 1.25 mg bupivacaine, 25 microg epinephrine, and 5 microg (5-microg group). Pain relief was assessed 10 min after injection, and pruritus was recorded at 30 min by a blinded observer. The study ended when the parturients requested further analgesia. There were no demographic differences among groups. Ninety of 103 parturients achieved complete pain relief with the initial dose, 11 patients in the control group (P < 0.004, control versus both sufentanil groups), and 2 patients in the 2.5-microg group needed a supplemental epidural bupivacaine. Pruritus was absent in the control group (P < 0.0001, control versus both sufentanil groups), whereas it was present in 36% of the 2.5-microg group and in 66% of the 5-microg group (P = 0.015, 2.5-microg versus 5-microg group). The mean duration of analgesia was similar in patients receiving sufentanil (2.5-microg group: 133 +/- 55 min; 5-microg group: 142 +/- 52 min) but was significantly higher than the control group (56 +/- 32 min). Reducing the sufentanil dose from 5 microg to 2.5 microg when combined with bupivacaine and epinephrine, decreases the incidence of pruritus without impeding the quality or duration of analgesia. IMPLICATIONS: We evaluated two different doses of intrathecal sufentanil combined with bupivacaine and epinephrine for labor analgesia. Sufentanil 2.5 microg offered an advantage over sufentanil 5 microg because, while providing the same quality and duration of analgesia, it was associated with a reduced incidence of pruritus.

Adult↗

Labour analgesia in a patient with carnitine palmityl transferase deficiency and idiopathic thrombocytopenic purpura.

We report a case of a woman with carnitine palmityl deficiency (CPT) and idiopathic thrombocytopenic purpura, presenting in active labour at 38 weeks gestation. We discuss different anaesthetic factors involved with both diseases, and we propose an optimal management of such cases. Neuraxial analgesia with minimal motor blockade is indicated in early labour because it is necessary to alleviate stress in order to avoid rhabdomyolisis associated with CPT deficiency. Neuraxial analgesia is also needed because the theoretical risk of performing a caesarean section is higher than in a normal population, first because labour must be kept as short as possible and secondly because the possible thrombocytopenic in the baby precludes the use of instrumental delivery.

Journal Article↗

Bilateral mydriasis during laparoscopic surgery.

Peritoneal insufflation with CO2 has been associated with profound cardiorespiratory disturbances, which may modify cerebral blood flow (CBF), particularly in hypertensive patients in whom CBF autoregulation is altered. We report a case of bilateral mydriasis during laparoscopic gastrectomy in a patient with chronic hypertension followed by a coma lasting several hours and we shortly discuss the possible mechanisms involved.

Carbon Dioxide↗

Changes in pulmonary mechanics during laparoscopic gastroplasty in morbidly obese patients.

BACKGROUND: Obesity is an important respiratory risk factor after abdominal surgery. Laparoscopic surgical techniques seem beneficial in obese patients in terms of respiratory morbidity, with a faster return to normal respiratory function. However, there is little information about intraoperative respiratory mechanics and about patient tolerance to abdominal insufflation in the morbidly obese. METHODS: We studied respiratory mechanics and arterial blood gases in 15 morbidly obese patients (mean BMI = 45) undergoing laparoscopic gastroplasty under general anaesthesia and controlled ventilation. Respiratory mechanics were analysed using side-stream spirometry. RESULTS: When compared to preinsufflation values, servocontrolled abdominal insufflation to 2.26 kPa caused a significant decrease in respiratory system compliance (31%), a significant increase in peak (17%) and plateau (32%) airway pressures at constant tidal volume with a significant hypercapnia but no change in arterial O2 saturation. Respiratory system compliance and pulmonary insufflation pressures returned to baseline values after abdominal deflation. CONCLUSION: These alterations in pulmonary mechanics are less than those observed with comparable degrees of abdominal inflation in non-obese patients, and were well tolerated. From the point of view of intraoperative respiratory mechanics, laparoscopic surgery is safe in morbidly obese patients.

Adult↗

Hemodynamic changes during laparoscopic gastroplasty in morbidly obese patients.

BACKGROUND: In nonobese patients, peritoneal insufflation has consistently been shown to influence parameters of preload and afterload as well as cardiac output. Obese patients have an abnormal and particular cardiovascular status. The aim of this study was to investigate the hemodynamic changes induced by an increase of intra-abdominal pressure in morbidly obese patients (MOP). METHODS: Standard general anesthesia was administered to 15 informed MOP (body mass index > 40 kg/m2) scheduled for laparoscopic gastroplasty. Hemodynamic parameters were measured by thermodilution through a pulmonary artery catheter and through invasive blood pressure monitoring. RESULTS: CO2 insufflation with an intra-abdominal pressure of 17 mmHg caused a significant increase of mean arterial pressure (MAP) (33%, P = 0.005), mean pulmonary arterial pressure (MPAP) (40%, P = 0.001), pulmonary capillary wedge pressure (PCWP) (41%, P = 0.001), and central venous pressure (CVP) (55%, P = 0.001). The increase in diastolic filling pressures could be due to an increase in the filling volume or to a decrease in diastolic compliance. Ventricular volumes were not measured but we speculate that the rise in CVP, PCWP and MPAP is due to an increase in intrathoracic pressure as judged by the increase of pulmonary airway pressure. Stroke volume fell slightly (11%, P = 0.008), because of a reduction in transmural pressure and a fall in effective preload. Cardiac output rose slightly (16%, P = 0.005) because of an increase in heart rate (15%, P = 0.014) probably induced by sympathetic stimulation, which only became fully operative after 15 minutes. CONCLUSIONS: When compared to nonobese patients our obese patients tolerated the pneumoperitoneum surprisingly well, without experiencing fall in cardiac output. The hemodynamic consequences of peritoneal insufflation seem to be different in obese and nonobese patients.

Adult↗

Transient radicular irritation followed by meningitis after spinal anesthesia.

Neurotoxicity of spinally administered hyperbaric 5% lidocaine is becoming a serious concern in view of the recent literature. We report a case of probable neurotoxicity of hyperbaric 5% lidocaine, followed by an aseptic meningitis. This case report emphasizes the danger of using hyperbaric 5% lidocaine in a too high dose while performing spinal anesthesia.

Adult↗

Methaemoglobinemia induced by a low dose of prilocaïne during interscalenic block.

Methaemoglobinemia is a rare but well known complication of the use of prilocaïne in locoregional anaesthesia. We report a case of methaemoglobinemia following the administration of a low dose of prilocaïne for an interscalenic bloc. We suggest some hypotheses to explain this phenomenon. This case illustrates the necessity of pulse oximetry monitoring in all patients receiving prilocaïne during locoregional anaesthesia.

Adult↗