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C Mann

Publications and source records attributed to C Mann.

At least 55 records · Page 3Linked to original sources
PubMed1999

The relationship among carbon dioxide pneumoperitoneum, vasopressin release, and hemodynamic changes.

UNLABELLED: We assessed the role of vasopressin (VP) for the hemodynamic response to pneumoperitoneum in pigs. Four groups of anesthetized pigs were investigated. Nine pigs were intraabdominally insufflated with CO2 and eight were intraabdominally insufflated with argon; eight pigs received an i.v. injection of 1 mg/kg SR 49059, a VP antagonist, before CO2 insufflation; and six pigs received SR 49059 alone. Hemodynamics, plasma concentrations of VP and vasoactive hormones, and Paco2 were measured. Data were analyzed by using analysis of variance, Student's t-test, and Mann-Whitney U-test. Five minutes after insufflation, changes in systemic vascular resistance (SVR) were significantly correlated with changes in VP (r = 0.72; P = 0.005) but not with changes in epinephrine, norepinephrine, renin activity, or Paco2. SVR increased during CO2 insufflation but not during argon insufflation or CO2 insufflation with a preceding infusion of SR 49059. The SR 49059 injection itself resulted in increases in heart rate and cardiac output and decreases in blood pressure and SVR. We conclude that, during CO2 pneumoperitoneum in pigs, absorbed CO2 initiates a pathophysiological process that stimulates VP release. Hence, VP most likely plays a key role in the hemodynamic response to a CO2-induced pneumoperitoneum. IMPLICATIONS: Intraabdominal insufflation of CO2 is associated with hemodynamic and hormonal changes. Investigating CO2 and argon-insufflated pigs and using a vasopressin antagonist, we found that CO2 insufflation released vasopressin, which, in turn, induced hemodynamic perturbances.

Animals↗
PubMed1998

[Ambulatory surgery in French public hospitals. Present and future. "Public hospitals" group of the French Association of Ambulatory Surgery].

OBJECTIVES: To assess ambulatory surgery practices in France, make an inventory of projects for the creation of ambulatory structures and analyze the perception of different hospital personnel of ambulatory surgery. METHODS: A questionnaire was sent to 541 public hospitals with a surgery unit in France. The first part of the questionnaire was used to record current activity and existing projects for ambulatory surgery. The questionnaire also collected opinions concerning the analysis of difficulties encountered and possibilities offered by ambulatory surgery. RESULTS: Overall participation rate was 59%. Ambulatory surgery was practised in 81% of the hospitals. Sixty-six percent had a projects under consideration, including several at the decision making stage (17%). 1550 ambulatory surgery clinics could be created by the year 2000. In 66% of the cases, the future facility would be integrated into the traditional surgery unit. There was favorable opinion concerning the development of ambulatory surgery clinics in public hospitals in 83% of the cases. Inconveniences suggested generally involved organizational aspects, particularly concerning medical organization. Foreseen obstacles to the development of ambulatory surgery clinics were regulatory procedures, unfavorable exchange rate, insufficient investment funds and the lack of a policy favoring their development. CONCLUSION: The development of ambulatory surgery clinics in public hospitals in France can be expected in the near future. Budgeting and regulatory procedures must however be adapted to promote implementation of the existing projects.

Attitude of Health Personnel↗
PubMed1998

Improved postoperative analgesia with isoflurane than with propofol anaesthesia.

PURPOSE: The impact of hypnotic drugs on postoperative analgesia has not been evaluated. We compared the influence of the maintenance of anaesthesia with either propofol or isoflurane on postoperative pain. METHODS: Forty ASA 1-2 women, undergoing cosmetic abdominoplasty were randomized to receive either 6-12 mg.kg-1.hr-1 propofol i.v. (P, n = 20) or MAC 1-1.5 isoflurane inhalation (Iso, n = 20). The lungs were ventilated with N2O 60% and O2 40%, and 1 microgram.kg-1 fentanyl i.v. provided intraoperative analgesia. Before surgical closure, 2 g propacetamol i.v. were administered. Postoperative analgesia was provided after hourly assessment of pain (VAS 0-100 mm), with 10 mg nalbuphine i.v. if VAS > or = 50 mm, during the eight hours after surgery. Sedation score (awake 0 to unrousable 4) was also recorded. Analgesia satisfaction score (nil 0 to excellent 4) obtained from the patient on discharge. RESULTS: Sedation scores were similar in both groups except in the first postoperative hour, when it was higher in the Iso group. The VAS at rest (15.4 +/- 18.6 vs 29.7 +/- 19.8 mm, P = 0.0001) and nalbuphine requirements (0.13 +/- 0.35 vs 0.70 +/- 0.80 doses, P = 0.004) were lower in the Iso group during the first six hours, although emesis was more frequent than in P (60 vs 25%; P = 0.03). The incidence of analgesia satisfaction score (> or = 3) was similar between the two groups (P: 95; Iso: 75%). CONCLUSION: These results suggested that isoflurane anaesthesia provides better analgesia than propofol anaesthesia in the first six hours after abdominoplasty.

Abdomen↗
PubMed1998

[Acute myopericarditis following laparoscopic treatment of gastroesophageal reflux].

A 32-year-old patient experienced a postoperative acute myopericarditis following laparoscopic surgery for gastro-oesophageal reflux (Toupet's fundoplication). His medical history was unremarkable, apart from controlled arterial hypertension. Peroperative circulation was stable, except a short hypertensive episode at CO2 insufflation, controlled with nicardipine. A myopericarditis occurred at the fourth postoperative hour, with apical and inferior hypokinesia at ventriculography, ST-segment elevation with unremarkable coronary arteriography. The patient was discharged at day seven, with a NSAIDs treatment. Echocardiography three and nine months later postoperatively, showed an apical akinesia and persistence of the ST-segment modification, without clinical symptoms. Complications of laparoscopic fundoplication is either specific to surgery (gastro-oesophageal injury, diaphragmatic injury, mediastinitis, stenosis) or secondary to pneumoperitoneum (pneumothorax, carbon dioxide embolism). In this case, following an apparently uncomplicated laparoscopy and, except a direct cardiac trauma from a laparoscopic instrument, either coronary artery spasm, or pneumopericardium with CO2, or delayed gas embolism, or preoperative "silent" myopericarditis could be the potential cause of this cardiac complication.

Acute Disease↗
PubMed1998

Haemodynamic heterogeneity and treatment with the calcium channel blocker nicardipine during phaeochromocytoma surgery.

BACKGROUND: Favourable outcome of phaeochromocytoma surgery requires that paroxysmal hypertension and arrhythmia be controlled, and that hypotension be prevented. Is nicardipine, a calcium channel blocking drug, always adequate? METHODS: Nineteen consecutive patients underwent surgery for phaeochromocytoma. Management was standardised with regards to anaesthesia and antihypertensive treatment. Nicardipine was used as a vasodilator and was given in order to maintain systemic vascular resistance lower than 1600 dyn.s.cm-5. RESULTS: Hypertension did not occur at any time during surgery in 6/19 patients. Blood pressure rose acutely in 3/19 patients at the time of tracheal intubation or surgical approach to the tumour, and was controlled by increased depth of anaesthesia. Hypertensive episodes occurred in 11/19 patients during tumour manipulation. Nicardipine always succeeded in maintaining low systemic vascular resistance but its dosage varied widely between patients (0.5 to 70 mg), a fact that may be accounted for by the striking intersubject variability of haemodynamic behaviour during surgery. In 7/11 patients, despite nicardipine treatment, sustained increase in blood pressure persisted with increased cardiac index, but low systemic vascular resistance. Following tumour removal, transient serious hypotension (MAP < 60 mmHg) occurred in 4 patients, and was corrected by fluid volume expansion. Perioperative incidence of hypertension or hypotension was not related to preoperative clinical status. CONCLUSION: Adequate management of patients operated upon for phaeochromocytoma requires invasive monitoring, since the mechanisms underlying hypertensive crises are heterogeneous with regards to systemic vascular resistance and not predictable from preoperative data. Nicardipine provides a good control of vasoconstriction during phaeochromocytoma surgery with limited risk of serious hypotension after tumour removal.

Adrenal Gland Neoplasms↗
PubMed1997

Quantitative determination of CGP 61755, a protease inhibitor, in plasma and urine by high-performance liquid chromatography and fluorescence detection.

A liquid chromatographic assay for the determination of CGP 61755 (I) in plasma and urine is described. A similar method for CGP 53437, another HIV-1 protease inhibitor, has been developed and reported previously. After a deproteinization step, a liquid-liquid extraction is performed. Compound I and the internal standard CGP 55749 (II) are hydrolyzed and the primary amine group derivatized using fluorescamine. Chromatography is achieved by isocratic elution with a mobile phase of 30 mM borax buffer (pH 9)-acetonitrile (58:42, v/v). The derivatives of the compounds I and II fluoresce at 480 nm, on excitation at 395 nm and the retention times under these conditions were approximately 6 and 8 min, respectively. The limit of quantitation (LOQ) which is the lowest concentration of the analyte that can be measured with a coefficient of variation and a deviation from theory of less than 20%, was 15 ng/ml plasma and 20 ng/ml urine. The analyte is stable for at least four months in human plasma and sixteen months in dog plasma samples. Different human plasma sources and three different species (rat, rabbit and dog) were tested and no interference between analyte and plasma constituents was observed.

Administration, Oral↗
PubMed1997

Argon pneumoperitoneum is more dangerous than CO2 pneumoperitoneum during venous gas embolism.

UNLABELLED: We investigated the possibility of using argon, an inert gas, as a replacement for carbon dioxide (CO2). The tolerance of argon pneumoperitoneum was compared with that of CO2 pneumoperitoneum. Twenty pigs were anesthetized with enflurane 1.5%. Argon (n = 11) or CO2 (n = 9) pneumoperitoneum was created at 15 mm Hg over 20 min, and serial intravenous injections of each gas (ranging from 0.1 to 20 mL/kg) were made. Cardiorespiratory variables were measured. Transesophageal Doppler and capnographic monitoring were assessed in the detection of embolism. During argon pneumoperitoneum, there was no significant change from baseline in arterial pressure and pulmonary excretion of CO2, mean systemic arterial pressure (MAP), mean pulmonary artery pressure (PAP), or systemic and pulmonary vascular resistances, whereas CO2 pneumoperitoneum significantly increased these values (P < 0.05). During the embolic trial and from gas volumes of 2 and 0.2 mL/kg, the decrease in MAP and the increase in PAP were significantly higher with argon than with CO2 (P < 0.05). In contrast to CO2, argon pneumoperitoneum was not associated with significant changes in cardiorespiratory functions. However, argon embolism seems to be more deleterious than CO2 embolism. The possibility of using argon pneumoperitoneum during laparoscopy remains uncertain. IMPLICATIONS: Laparoscopic surgery requires insufflation of gas into the peritoneal cavity. We compared the hemodynamic effects of argon, an inert gas, and carbon dioxide in a pig model of laparoscopic surgery. We conclude that argon carries a high risk factor in the case of an accidental gas embolism.

Animals↗
PubMed1997

The detection of carbon dioxide embolism during laparoscopy in pigs: a comparison of transesophageal Doppler and end-tidal carbon dioxide monitoring.

BACKGROUND: The aim of the study was to compare the value of transesophageal Doppler and end-tidal carbon dioxide monitoring to detect venous carbon dioxide embolism in pigs during laparoscopic cholecystectomy. METHOD: Ten pigs were anesthetized under constant ventilation, and instrumented for laparoscopic cholecystectomy. CO2 pneumoperitoneum was performed at 15 mmHg and then, successive increased intravenous gas boluses of 0.1 to 4 ml/kg injected through the femoral vein using a 55-mm long catheter. The responses indicative of embolism were defined as: 1) a change in Doppler tone placed facing the junction of the right atrium and inferior vena cava; 2) a change in end-tidal CO2 > or = 0.4 kPa. RESULTS: Doppler was more sensitive in detecting 0.1, 0.2 and 0.4 ml/mg of CO2 embolism than end-tidal CO2 (P < 0.05). Over 0.4 ml/mg no differences in sensitivity were found but the Doppler signal modifications occurred earlier than the changes in end-tidal CO2. Moreover, these changes always consisted of a reduction of the value. CONCLUSION: During laparoscopic cholecystectomy in pigs, transesophageal Doppler was a highly sensitive monitor which provided an earlier detection of CO2 embolism and at lower doses than end-tidal CO2 monitoring.

Animals↗
PubMed1997

Multiple eruptive dermatofibromas in three men with HIV infection.

BACKGROUND: Multiple eruptive dermatofibromas (MEDF) are rare and their etiology is unknown. An association with immunosuppression has led to the speculation that they are the result of an abortive immunoreactive process. In the literature, there have been 5 isolated case reports of multiple dermatofibromas and human immunodeficiency virus (HIV) infection. Three of these cases had other immune modulators present (i.e. prednisone, systemic lupus erythematosus, alpha-interferon, UVB phototherapy). The other 2 cases had disseminated mycobacteriosis. OBSERVATIONS: A series of 3 men with HIV infection and MEDF is described. In contrast to previous case reports, our patients did not have other immune modulators besides HIV infection nor did they have disseminated mycobacteriosis. CONCLUSIONS: This series lends support to the speculation that MEDF may be associated with immunosuppression. Further study is needed to delineate the exact mechanism for this relationship. These patients presented within a 4-month period and illustrate the frequency at which MEDF may be seen in the HIV-positive population. As clinicians who care for patients with HIV infection, it is important to be aware that MEDF may be seen in this immunosuppressed population.

Adjuvants, Immunologic↗
PubMed1997

A yeast heat shock transcription factor (Hsf1) mutant is defective in both Hsc82/Hsp82 synthesis and spindle pole body duplication.

Cdc28 is a cyclin-dependent protein kinase of Saccharomyces cerevisiae that is required for the G1/S and G2/M transitions of the cell division cycle. All previously described cdc28 mutants aside from cdc28-1N arrest division specifically in the G1 phase. cdc28-1N arrests division in G2/mitosis. We show here that the cdc28-109 mutant exhibits a mixed cell division arrest at 37 degrees C with cells in both the G1 and G2 phases. In order to identify proteins that functionally interact with Cdc28, we isolated mutants that are colethal with cdc28-109 at its permissive temperature. We describe here our phenotypic analysis of two such mutants, hsf1-82 and ydj1-10, that affect the heat shock transcription factor and a yeast dnaj-like protein chaperone, respectively. hsf1-82 and ydj1-10 temperature-sensitive mutants arrest the cell division cycle at several stages. However, one predominant class of cells in both mutants was arrested with a large bud and a single vertex of microtubules. Electron microscopic analysis of such hsf1-82 cells showed that they contained an unduplicated spindle pole body with an enlarged half-bridge. Two-dimensional gel electrophoresis of total cell proteins revealed that the hsf1-82 cells were specifically defective in the expression of the Hsc82 and Hsp82 proteins. Furthermore, the hsf1-82 mutation was suppressed by the HSC82 gene on a multicopy plasmid that restored Hsc82 protein to high levels in these cells. These results show that Hsf1 is required for spindle pole body duplication at 37 degrees C.

Alleles↗