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M Georgieff

Publications and source records attributed to M Georgieff.

At least 127 records · Page 7Linked to original sources

In vivo quantification of endotoxin-induced nitric oxide production in pigs from Na15NO3-infusion.

1. In this investigation the NO production rate is quantified in the pig during normotensive endotoxin-induced shock with increased cardiac output and during subsequent treatment with the NO synthase inhibitor N omega-monomethy-L-arginine (L-NMMA). NO production rate was derived from the plasma isotope-enrichment of 15N-labelled nitrate (15NO3-). 2. Three groups of animals (control, n = 5; endotoxin, n = 6; endotoxin + L-NMMA, n = 6) were anaesthetized and instrumented for the measurement of systemic and pulmonary haemodynamics. Each animal received a primed-continuous infusion of stable, non-radioactively labelled Na15 NO3 (bolus 30 mg, infusion rate 2.1 mg h-1). Arterial blood samples were taken 5, 10, 15, 30, 60 and 90 min later and every 90 minutes until the end of the experiment. 3. Continuous i.v. infusion of endotoxin was incrementally adjusted until mean pulmonary artery pressure (PAP) reached 50 mmHg and subsequently titrated to keep mean PAP approximately 35 mmHg. Hydroxyethylstarch was administered as required to maintain mean arterial pressure (MAP) > 60 mmHg. Six hours after the start of the endotoxin continuous i.v. L-NMMA (1 mg kg-1 h-1) was administered to the endotoxin + L-NMMA group. Haemodynamic data were measured before as well as 9 h after the start of the endotoxin. 4. After conversion of NO3- to nitro-trimethoxybenzene and gas chromatography-mass spectrometry analysis the total NO3- pool, basal NO3- production rate and the increase per unit time in NO3- production rate were calculated from the time-course of the 15NO3- plasma isotope-enrichment. A two compartment model was assumed for the NO3- kinetics, one being an active pool in which newly generated NO3- appears and from which it is eliminated, the other being an inactive volume of distribution in which only passive exchange takes place with the active compartment. 5. Although MAP did not change during endotoxin infusion alone, cardiac output (CO) increased by 42 +/- 40% (P < 0.05 versus baseline) by the end of the experiment due to a significant (P < 0.05 versus baseline) fall in systemic vascular resistance (SVR) to 65 +/- 25% of the baseline value. L-NMMA given with endotoxin did not change MAP, and both CO and SVR were maintained close to the pre-shock levels. 6. Baseline plasma NO3- concentrations were 43 +/- 13 and 40 +/- 10 mumol l-1 in the control and endotoxin animals, respectively, and did not differ at the end of the experiment (39 +/- 8 and 44 +/- 15 mumol l-1, respectively). The mean NO3- pool and basal NO3- production rate were 1155 +/- 294 mumol and 140 +/- 32 mumol h-1, respectively, without any intergroup difference. Endotoxin significantly increased NO3- production rate (23 +/- 10 mumol h-2, P < 0.05 versus control (6 +/- 7 mumol h-2) and endotoxin + L-NMMA groups). L-NMMA given with endotoxin (-1 +/- 2 mumol h-2, P < 0.05 versus control and endotoxin groups) had no effect. 7. Analysis of the time course of the 15NO3- plasma isotope enrichment during primed-continuous infusion of Na15NO3 allowed us to quantify the endotoxin-induced increase in NO3- production rate independently of total NO3- plasma concentrations. Low-dose L-NMMA blunted the increase in NO3- production rate while maintaining basal NO3- formation.

Animals↗

[Xenon].

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Anesthesia, Closed-Circuit↗

[Effectiveness of anesthetic gas scavengers fulfilling EN 740 requirements with reference to equipment leakage and fresh gas flow].

PURPOSE: During inhalation anaesthesia, contaminations of the working environment be anaesthetic volatiles and nitrous oxide occur. The amount of leaking gases is influenced by leakages of the anaesthetic ventilator, by fresh-gas flows and by the effectivity of the scavenging system. Since 1st January 1996 new ventilators have to be equipped with scavenging devices according to the European standard EN 740. We measured the effectivity of this system with anaesthetic ventilators of a type that is now superseded (mean leakage rate 100 ml/min) and recent devices (mean leakage rate 5 ml/min) using high and low fresh-gas flows. MATERIAL AND METHODS: The anaesthetic ventilators were placed in a non-air-conditioned area. A test lung was ventilated with gas flows of 1 l/min, 3 l/min and 6 l/min (concentrations of nitrous oxide 70%, Enflurane 1%). The ventilation time in each case was 1 h. The minute volume was set to 8 l/min. At 2-minute intervals the concentrations of nitrous oxide and enflurane were measured by a multigas monitor Brüel & Kjaer 1302. The experiments were carried out with an old scavenging device according to DIN 13260 and a new device according to EN 740. RESULTS: Using the scavenging device according to DIN 13260, the concentrations of the pollutant gases were significantly dependent on the fresh-gas flows. No differences were found when using old or new anaesthetic ventilators. Medians of nitrous oxide (n2o) and Enflurane (e): 6 l/min: (n2o) 204 ppm (e) 4.3 ppm 3 l/min: (n2o) 115 ppm (e) 2.1 ppm 1 l/min: (n2o) 61 ppm (e) 0.97 ppm. Scavenging devices according to EN 740 significantly reduced the amount of emitted pollutants. No dependency on fresh-gas flows could be detected. 6 l/min: (n2o) 11.25 ppm (e) 0.05 ppm 3 l/min: (n2o) 10.12 ppm (e) 0.0 ppm 1 l/min: (n2o) 9.5 ppm (e) 0.0 ppm. CONCLUSIONS: The formerly reported dependence of the room air concentrations of anaesthetic volatiles and nitrous oxide from the fresh gas flow are caused by the spillage of pollutants through scavenging devices according to DIN 13260. The use of systems according to EN 740 is not only useful in new devices but must also be recommended for superseded models of anaesthetic ventilators.

Air Pollutants, Occupational↗

[Effectiveness, side effects and costs of postoperative pain therapy: intravenous and epidural patient-controlled analgesia (PCA)].

PURPOSE: Improvement of the quality of analgesia, reduction of side effects and costs by application of epidural (PCEA) in comparison to intravenous patient-controlled analgesia (PCA) in postoperative pain treatment. METHODS: 62 patients with upper abdominal surgery took part in this randomised prospective study which was approved by the local ethics committee. Epidural catheters were inserted at T 8/9 (group PCEA). General anaesthesia was performed with propofol, sufentanil 2 micrograms/kg, pancuronium, enflurane and O2:N2O = 1:2. Postoperative analgesia consisted of epidural bupivacaine 0.25% + sufentanil 2 micrograms/ml (BS). (bolus 0.05 ml/kg, lockout 10 min) in group PCEA, or of intravenous morphine (bolus 2 mg. lockout 10 min) in group PCA. The following parameters were recorded until the evening of postoperative day 4: pain intensity at rest (VASR, 1-10) and on coughing (VASH, 1-10), blood pressure, heart rate, blood gas analysis, ability to ambulate, pruritus, nausea/vomiting (PONV), patient satisfaction (0-4), time and expenses for postoperative pain treatment. RESULTS: Median VASR (1 vs 2) and VASH (3 vs 4.5) were lower, cough intensity (2 vs 1) and patient satisfaction score (4 vs 3) were higher in PCEA compared to PCA. Ability to ambulate, pruritus, PONV, haemodynamics, paO2 and paCO2 were comparable. Postoperative pain treatment with PCEA was more time-consuming (407 vs 299 min) and expensive (71 vs 40 S/day) than PCA. CONCLUSION: PCEA in comparison to PCA after major abdominal surgery provides superior analgesia with comparable side effects at approximately 80% higher costs.

Abdomen↗

[Differential indications for non-opioids for postoperative analgesia III. Analgesic effect of perioperative administration of metamizole plus diclofenac after spinal anesthesia].

PURPOSE: In a previous study we investigated the analgesic efficacy of a combination of metamizol plus diclofenac after general anaesthesia. After minor orthopaedic surgery postoperative opioid requirements were reduced by 73% during the first 24 h after surgery. In the present study, we have investigated the efficacy of this analgesic combination after minor orthopaedic operations performed in spinal anaesthesia. METHODS: Seventy four patients, scheduled for minor orthopaedic surgery, participated in this double-blind, randomised, placebo-controlled study. The setting was comparable to our previous study. Before induction of spinal anaesthesia, verum-treated patients received a diclofenac suppository (100 mg), and metamizol (1 g/100 ml NaCl 0.9% intravenously over 15 min). These infusions were repeated at 6 h and 12 h. In addition to the third infusion, the patients received a further diclofenac suppository (100 mg). Cumulated doses of buprenorphine (PCA, patient-controlled analgesia), pain scores (0-10), blood pressure, heart rate and side effects were recorded during the first 6 h and again at 24 h. RESULTS: After spinal anaesthesia had subsided, all patients required increasing doses of buprenorphine. Verum-treated patients required significantly lower doses during the first 24 h after surgery (median -29%). CONCLUSIONS: The combination of metamizol and diclofenac causes a clinically relevant reduction in opioid requirements after minor orthopaedic surgery in spinal anaesthesia.

Adult↗

Effects on haemodynamics and catecholamine release of xenon anaesthesia compared with total i.v. anaesthesia in the pig.

In order to investigate haemodynamic response and catecholamine release during anaesthesia with xenon, we conducted a study on 28 pigs which were allocated randomly to one of four groups: total i.v. anaesthesia with pentobarbitone and buprenorphine, and xenon anaesthesia with inspiratory concentrations of 30%, 50% or 70%, respectively, supplemented with pentobarbitone. Haemodynamic variables were measured using arterial and Swan Ganz catheters. Depth of anaesthesia was monitored using spectral edge frequency analysis. Plasma concentrations of dopamine, noradrenaline and adrenaline were measured by high pressure liquid chromatography. All haemodynamic variables and plasma concentrations of dopamine and noradrenaline remained within normal limits. Adrenaline concentrations were reduced significantly in all groups. Xenon anaesthesia was associated with a high degree of cardiovascular stability. Significant reduction in adrenaline concentrations at inspiratory xenon concentrations of 30% and 50% can be explained by analgesic effects of xenon below its MAC value.

Anesthetics, Inhalation↗

Reduced postoperative analgesic demand after inhaled anesthesia in comparison to combined epidural-inhaled anesthesia in patients undergoing abdominal surgery.

We studied the effect of epidural/general combination anesthesia, in comparison to inhaled anesthesia, on postoperative pain and analgesic consumption in patients undergoing upper abdominal surgery. Anesthesia was induced with propofol and maintained with enflurane in 70% N2O as necessary to maintain arterial blood pressure within 20% of baseline. Group I received bupivacaine 0.25% 0.2 mL/kg and sufentanil 1 microgram/kg 65 +/- 3 min before dermal incision and 0.1 mL/kg bupivacaine 0.25% + sufentanil 2 micrograms/mL (BS) every hour thereafter. Group II received 0.2 mL/kg of BS 316 +/- 15 min after dermal incision in the recovery room. Postoperative patient-controlled epidural analgesia (PCEA) with BS was provided. Pain intensities and consumption of PCEA BS were recorded on postoperative days (PODs) 1 to 5. Inspiratory fraction of enflurane was lower (0.5% +/- 0.01% vs 1.6% +/- 0.04%; P < 0.001) in Group I compared with Group II. Cumulative postoperative consumption of PCEA BS was higher in Group I compared with Group II from the evening of POD 2 until the end of the study (301 +/- 19 mL vs 249 +/- 17 mL; P < 0.001), while pain intensities were comparable at all times. The intraoperative effects of combined BS and enflurane/N2O (inspiratory fraction [Fi] approximately 1 minimum alveolar anesthetic concentration [MAC]) did not preempt postoperative pain in contrast to enflurane/N2O anesthesia (Fi approximately 2.8 MAC).

Abdomen↗

The impact of prostanoids on pulmonary gas exchange during abdominal surgery with mesenteric traction.

We investigated the effect of intravenous (iv) ibuprofen on prostanoid release and on pulmonary gas exchange after abdominal mesenteric traction (MT) during either abdominal aortic surgery or pancreas resection. In a prospective, randomized, double-blind study, 400 mg ibuprofen (pancreas n = 13, aorta n = 13) or a placebo (pancreas n = 13, aorta n = 13) was administered iv before skin incision. MT was applied uniformly. The prostanoid plasma concentrations, venous admixture (Q(va)/Q(t)), and PaO2/FIO2 ratio were determined at baseline (before MT) and 5, 15, 45, and 90 min after MT. Patients who underwent aortic surgery were older and exhibited a lower preoperative PaO2 than those who underwent pancreas resection. Placebo-treated patients revealed a 30-fold peak increase in 6-keto-prostaglandin F1alpha (stable metabolite of prostacyclin) levels after intentional MT during aortic as well as pancreatic operations. This response was accompanied by an increase in Q(va)/Q(t) (ibuprofen: pancreas 7% +/- 1%, aorta 14% +/- 2%; placebo: pancreas 16% +/- 3%, aorta 26% +/- 3%/15 min after MT [mean +/- SEM, P < 0.05, placebo vs ibuprofen]), which resulted in decreased PaO2/ FIO2 ratio only in the aortic surgery patients (ibuprofen: 310 +/- 19; placebo: 237 +/- 24 15 min after MT, [mean +/- SEM, P < 0.05]). The authors conclude that ibuprofen-pretreated patients demonstrated almost constant prostanoid levels without changes in pulmonary gas exchange after MT.

6-Ketoprostaglandin F1 alpha↗

Epidural bolus clonidine/morphine versus epidural patient-controlled bupivacaine/sufentanil: quality of postoperative analgesia and cost-identification analysis.

UNLABELLED: We compared the costs, quality of analgesia, and side effects of postoperative patient-controlled epidural analgesia (PCEA) with bupivacaine/sufentanil versus an epidural bolus (BOLUS) of clonidine/morphine in 68 patients with pancreatic surgery. Postoperative pain treatment was performed over 4 days: the PCEA pump was filled with bupivacaine 0.25% and sufentanil 2 micrograms/mL and set to 3-mL bolus and 10-min lockout time. BOLUS patients received injections of clonidine 150 micrograms plus morphine 2 mg on demand. Visual analog scale (VAS) score at rest and during coughing, heart rate (HR), systolic arterial pressure (SAP), incidence of postoperative nausea and vomiting, pruritus, duration of intestinal paralysis, hospital treatment, and costs for personnel and material were recorded. VAS scores during coughing (3 +/- 2.5 vs 5 +/- 3, P < 0.001) was higher, and HR (79 +/- 13 vs 89 +/- 15, P < 0.001), and SAP (110 +/- 18 vs 124 +/- 23, P < 0.001) were lower, in the BOLUS compared with the PCEA group. The incidence of hypotension (SAP < 80 mm Hg) was greater (6 vs 0, P < 0.001) in the BOLUS group. The incidence of all other side effects was comparable. The costs of personnel ($204 +/- $40 vs $166 +/- $38, P < 0.001) were higher in the BOLUS group, but the costs of material ($51 +/- $17 vs $87 +/- $18, P < 0.001) were higher in the PCEA group. Total costs ($62 +/- $9 vs $62 +/- $11 per day, P = 0.9) were comparable. We conclude that because of superior analgesia and reduced side effects at analogous costs, PCEA is preferable to the BOLUS technique for the treatment of postoperative pain. IMPLICATIONS: An epidural clonidine/morphine bolus technique resulted in inferior analgesia, more side effects, and comparable costs compared with a bupivacaine/sufentanil patient-controlled regimen in a randomized controlled trial after abdominal surgery.

Adult↗

Effects of a dobutamine-induced increase in splanchnic blood flow on hepatic metabolic activity in patients with septic shock.

BACKGROUND: Septic shock leads to increased splanchnic blood flow (Qspl) and oxygen consumption (VO2spl). The increased Qspl, however may not match the splanchnic oxygen demand, resulting in hepatic dysfunction. This concept of ongoing tissue hypoxia that can be relieved by increasing splanchnic oxygen delivery (DO2spl), however, was challenged because most of the elevated VO2spl was attributed to increased hepatic glucose production (HGP) resulting from increased substrate delivery. Therefore the authors tested the hypothesis that a dobutamine-induced increase in Qspl and DO2spl leads to increased VO2spl associated with accelerated HGP in patients with septic shock. METHODS: Twelve patients with hyperdynamic septic shock in whom blood pressure had been stabilized (mean arterial pressure > or = 70 mmHg) with volume resuscitation and norepinephrine received dobutamine to obtain a 20% increase in cardiac index (CI). Qspl, DO2spl, and VO2spl were assessed using the steady-state indocyanine green clearance technique with correction for hepatic dye extraction, and HGP was determined from the plasma appearance rate of stable, non-radio-active-labeled glucose using a primed-constant infusion approach. RESULTS: Although the increase in CI resulted in a similar increase in Qspl (from 0.91 +/- 0.21 to 1.21 +/- 0.34l.min-1.m2; P < 0.001) producing a parallel increase of DO2spl (from 141 +/- 33 to 182 +/- 44 ml.min-1.m2; P < 0.001), there was no effect on VO2spl (73 +/- 16 and 82 +/- 21 ml.min-1.m2, respectively). Hepatic glucose production decreased from 5.1 +/- 1.6 to 3.6 +/- 0.9 mg.kg-1.min-1 (P < 0.001). CONCLUSIONS: In the patients with septic shock in whom blood pressure had been stabilized with volume resuscitation and norepinephrine, no delivery-dependency of VO2spl could be detected. Oxygen consumption was not related to the accelerated HGP either, and thus the concept that HGP dominates VO2spl must be questioned in well-resuscitated patients with septic shock.

Adrenergic beta-Agonists↗

Regulation of beta 2-adrenergic receptors on mononuclear leukocytes in patients with acute ischemic heart disease.

OBJECTIVE: To investigate relationships between acute adrenergic stress, plasma catecholamine concentrations, and beta 2-adrenergic receptors. DESIGN: Prospective, descriptive study. SETTING: Emergency medical service at a university hospital. PATIENTS: Twenty-seven patients with out-of-hospital cardiac arrest (n = 11), myocardial infarction (n = 6), and angina pectoris (n = 10), and 12 control subjects. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Mononuclear leukocyte beta 2-adrenergic receptor density and affinity were measured in patients 15 mins after successful cardiopulmonary resuscitation and after the diagnosis of myocardial infarction or angina pectoris, respectively, and were measured as well in control subjects. Plasma concentrations of catecholamines, glucose, and lactate were simultaneously measured with heart rate and blood pressure. After cardiac arrest, the density of beta 2-adrenergic receptors (1858 +/- 188 sites/cell [p < .01]), plasma epinephrine concentration (31,990 +/- 14,526 pg/mL [174.6 +/- 79.3 nmol/L] [p < .01]), heart rate (100 +/- 6 beats/min [p < .01]), glucose concentration (14.9 +/- 0.8 mmol/L [p < .01]), and lactate concentration (10.9 +/- 0.6 mmol/L [p < .01]) were increased in patients compared with those values in healthy controls. CONCLUSION: Acute maximal stress, such as after cardiac arrest, is associated with an increase in the density of beta 2-adrenergic receptors on mononuclear leukocytes derived from patients after successful cardiopulmonary resuscitation.

Acute Disease↗

Metabolic and calorigenic effects of dopexamine in healthy volunteers.

OBJECTIVE: To evaluate metabolic and calorigenic effects of dopexamine in healthy volunteers. DESIGN: Prospective, randomized trial. SETTING: Laboratory of the University Department of Anesthesiology. SUBJECTS: Eight volunteers. INTERVENTIONS: After a control period, dopexamine was administered using four infusion rates (0.75, 1.5, 3.0, and 6.0 microg/kg/min). MEASUREMENTS AND MAIN RESULTS: Blood pressure, heart rate, oxygen consumption (VO2), and the plasma concentration of potassium, glucose, lactate, and norepinephrine were measured. Typical hemodynamic responses were seen. VO2 increased from 122 +/- 11 (SD) to 150 +/- 9 mL/min/m2 during the highest dopexamine infusion rate. Plasma potassium concentration decreased only during the highest infusion rate. Plasma glucose concentration increased during infusion rates of 3 and 6 microg/kg/min of dopexamine, from 90 +/- 5 to 99 +/- 5 mg/dL (5.0 +/- 0.3 to 5.5 +/- 0.3 mmol/L), and from 87 +/- 7 to 103 +/- 11 mg/dL (4.8 +/- 0.4 to 5.7 +/- 0.6 mmol/L), respectively. Lactate did not increase during dopexamine infusion. Plasma norepinephrine concentration increased during all four infusion rates. CONCLUSION: It was not possible to differentiate the adrenergic receptor subtype responsible for the calorigenic and metabolic effects, since the putative beta2 adrenergic-receptor agonist, dopexamine, caused an increase in the plasma concentration of the beta1 adrenergic-receptor agonist, norepinephrine. Since beta2 adrenergic receptor-mediated effects such as hypokalemia were found only at infusion rates > or = 3 microg/kg/min, the effects of dopexamine at infusion rates < 3 microg/kg/min may be mainly mediated by stimulation of dopaminergic receptors and the indirect sympathomimetic action.

Adrenergic beta-Agonists↗

Effects of basic fibroblast growth factor on hippocampal neurons after axonal injury.

OBJECTIVE: Axons of adult central nervous system neurons fail to regenerate after diffuse axonal injury in head trauma. Basic fibroblast growth factor (bFGF) has been reported to enhance neuritic extensions after neuronal injury in immature nerve cells. To investigate the effects of bFGF on adult neurons and axonal reoutgrowth, differentiated nerve cells were axonally transected and bFGF was applied. DESIGN: Cell culture study with primary rat hippocampal neurons. MATERIALS AND METHODS: After axotomy, hippocampal cultures were maintained untreated or in the presence of 0.5, 1, 10, or 20 ng/mL bFGF and evaluated over a 7-day period after injury. MEASUREMENTS AND MAIN RESULTS: Seven days after injury, axotomy decreased cell survival to 65%, increased [3H]arachidonic acid release 1.8-fold from prelabeled cells, and showed negligible effects on neuronal dendrites. bFGF reduced this neurodegeneration at all doses applied. bFGF at 10 ng/mL most efficiently increased live cells to 85% and decreased [3H]arachidonic acid release from prelabeled cells to control values (p < 0.01, vs. damaged cells). Furthermore, 10 ng/mL bFGF induced axonal branching and the longest axonal re-extensions from 60 +/- 8 to 377 +/- 10 microns 7 days after injury (p < 0.01, vs. damaged cells). CONCLUSIONS: bFGF increased cell survival and supported axonal re-elongations in adult hippocampal neurons in vitro when applied after axotomy. bFGF may play a role in new therapeutic concepts for the management of axonal injury after head trauma.

Animals↗

Perioperative respiratory events in smokers and nonsmokers undergoing general anaesthesia.

BACKGROUND: The prevalence of respiratory diseases in smokers and nonsmokers and the incidence of perioperative respiratory events (PREs) were investigated for patients undergoing general anaesthesia. The aim was to quantify well-known problems and to identify possible new associations between smoking and PREs. METHODS: From July 1992 to December 1994, risk factors, demographic data, and PREs were documented by an automatically readable anaesthetic record (ARAR). PREs were used as defined by the German Society of Anaesthesiology and Intensive Care. RESULTS: Of 26961 subsequent anaesthesias in adults, 7122 (26.4%) were performed in smokers with a prevalence of chronic bronchitis of 23.3% (4.8% in nonsmokers). 1573 PREs occurred in 1397 (5.2%) of all anaesthetics. 459 events concerned intubation problems and problems in technical airway management. 1114 specific respiratory events (SPREs) like re-intubation, laryngospasm, bronchospasm, aspiration, hypoventilation/hypoxaemia and others had a total incidence of 5.5% in smokers and 3.1% in nonsmokers. The relative risk (RR) of SPREs was 1.8 in all smokers, 2.3 in young (16-39 years) smokers, and 6.3 in obese young smokers. The RR of perioperative bronchospasm was 25.7 in young smokers with chronic bronchitis. CONCLUSION: The impact of smoking on perioperative respiratory problems should make anaesthetists take this widespread preoperative condition seriously, particularly in young adults. The presented method of incident reporting (based on a national classification) could contribute to future research in anaesthetic epidemiology.

Adolescent↗

Shed mediastinal blood in 500 elective cardiac surgery patients: is there enough for retransfusion routinely?

OBJECTIVE: Since an increased use of several blood salvaging measures has contributed to a reduction in perioperative blood loss and the requirement for banked blood in recent years, the aim of this study was to establish current postoperative drainage losses in order to evaluate whether homologous retransfusion may be a useful measure to reduce autologous transfusion in elective cardiac surgery. DESIGN/SETTING: This prospective clinical investigation was performed at a University Intensive Care Unit during the first six hours following cardiac surgery. PATIENTS: 373 men and 127 women undergoing elective cardiac surgery were investigated. MEASURES: The amount of shed blood was measured four and six hours postoperatively. RESULTS: The average blood loss was higher in men than in women both in all operations as a whole (men, four hours: 223+/-73 ml, six hours 270+/-95 ml; women, four hours: 156+/-25 ml, six hours 195+/-22 ml), in valve replacement (men, four hours: 299+/-87 ml, six hours 350+/-101 ml; women, four hours: 187+/-30 ml, six hours: 219+/-31 ml) and in coronary artery bypass grafting (men, four hours: 197+/-69 ml, six hours: 242+/-83 ml; women, four hours: 128+/-15 ml, six hours: 173+/-18 ml). A blood loss of 400 ml was exceeded in 13% of men after valve replacement four and six hours postoperatively. In all other groups, less than 8% of patients had a loss of more than 400 ml both after four and after six hours. CONCLUSIONS: Postoperative drainage losses in elective cardiac surgery patients are small and a measurable advantage from retransfusion seems to be unlikely. We therefore endorse the routine use of shed mediastinal blood retransfusion in these patients.

Blood Loss, Surgical↗

The effect of basic fibroblast growth factor on glutamate-injured neuroarchitecture and arachidonic acid release in adult hippocampal neurons.

During development in culture, basic fibroblast growth factor (bFGF) protected immature primary hippocampal neurons against glutamate-induced neurotoxicity. We investigated the effects of bFGF on mature, differentiated rat hippocampal neurons cultured for 10-12 days after an 8-min exposure to 500 microM glutamate. Seven days post-injury, hippocampal cells demonstrated severe reductions in cellular viability and axonal and dendritic outgrowth, which were accompanied by a marked increase in [3H]arachidonic acid (ARA) release from prelabelled neurons. bFGF applied post-injury attenuated cell death and cytoarchitectural destruction at all concentrations used (500 pg/ml, 1, 10, 20 ng/ml). However, neurite elongation and branching processes were only significantly protected by 10 ng/ml bFGF. [3H]ARA release decreased in a dose-related fashion within a concentration range of 1-10 ng/ml bFGF. 20 ng/ml bFGF was not superior to 10 ng/ml bFGF. Therefore, bFGF's neurotropic actions appear to be concentration-dependent. Our data suggest that bFGF applied post-injury may have a neuroprotective potential for mature, differentiated, completely polarized hippocampal neurons.

Animals↗

The Erlanger Microlightguide Photometer: a new concept for monitoring intracapillary oxygen supply of tissue--first results and a review of the physiological basis.

The local oxygen supply to the skin immediately before and after withdrawal of blood was appraised in 18 healthy test subjects by measuring the intracapillary hemoglobin oxygenation (HbO2). The investigation was carried out with the Erlanger Microlightguide Photometer (EMPHO). EMPHO measurements are based on the registration of tissue remission spectra from which the HbO2 values are calculated using the Kubelka-Munk theory. The results show that global parameters do not reflect the supply of oxygen to the tissue; for example, in hypovolemia, the physiological response to the pathophysiological stimulus is centralization. This is manifested at a very early stage in the skin, before the oxygen supply to other organs (e.g., liver, kidney, gut) is affected. The disturbance of the local cutaneous oxygen supply is reflected in a change in the intracapillary hemoglobin oxygenation of the skin. Hence, one might consider measurements of the local oxygen supply to the skin as an early indicator for centralization.

Hemoglobinometry↗