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Biomedical subjects

G Strauss

Publications and source records attributed to G Strauss.

At least 37 records · Page 2Linked to original sources
PubMed2003

[Teleteaching in otorhinolaryngology. Part 2: the European database "medicstream"].

Searching the medical literature is mainly characterized by the use of databases. The time for reviewing and printing a paper causes a delay between the first presentation of scientific results in a lecture and the appearance of the appropriate journal publication. Moreover, the possibilities for the integration of multimedia data are limited. Because of the development of new compression algorithms for audiovisual digitization software, the near simultaneous transmission of scientific presentations, both visually and aurally, has been possible since 1999. The section telemedicine of the interdisciplinary study group on image guided surgical navigation from the University of Leipzig has developed "medicstream" as a unique, audiovisual, scientific internetdatabase. It allows the documentation of presentations at congresses and courses, including the discussion,over a freely accessible, widely available homepage, using a home developed streaming technology. All presentations are examined by an authorized editorial committee consisting of representatives with different medical specializations for content before the admission to the data base. A total of 392 presentations from seven scientific meetings can be selected by an integrated search machine and viewed with Windows Media Player or Real Player using a conventional or faster internet connection to the homepage www.medicstream.de. The quality of the audiovisual transmission depends on the receiver-lateral data transmission rate,whereby the minimum variant of 56 kB/s is characterized by good detectability of the contents. In an analysis period of 242 days,we registered 44,199 accesses and 4,488 attendances. The telemedicine data base "medicstream" can optimize quality and extend medical education by live-streaming as well as by archiving scientific presentations as audiovisual data.

Congresses as Topic↗
PubMed2003

Headspace solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) for the determination of 5alpha-androst-2-en-17-one and -17beta-ol in the female Asian elephant: application for reproductive monitoring and prediction of parturition.

Asian elephants are not self-sustaining in captivity. The main reasons for this phenomenon are a low birth rate, an aging population, and poor calf-rearing. Therefore, it is essential that reproductive rates had to be improved and there is need for rapid quantitative measures to monitor reproductive functions focussing on estrous detection and the prediction of the period of parturition. The objective of this study was to develop a method which combines headspace solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) for analyses of 5alpha-androst-2-en-17beta-ol and -17-one to prognose estrous and to predict the period of parturition. SPME was carried out with a CTC Combi Pal system. The course of the luteal phase-specific substance 5alpha-androst-2-en-17beta-ol and -17-one followed a cyclic pattern in which the follicular and luteal phases could be clearly distinguished (mean estrous cycle length, 15+/-1.4 weeks). Based on daily urine samples, estrous prognosis might be possibly based on the initial 5alpha-androst-2-en-17beta-o1 increase at the end of the follicular phase. Parturition prognosis was performed in three elephant cows based on the 5alpha-androst-2-en-17beta-o1 drop to baseline levels 5-4 days prior parturition. Experiments revealed that 5alpha-androst-3alpha-ol-17-one and probably 5alpha-androst-3alpha-ol-17beta-ol are generated from sulfate conjugates by a thermal process.

Androstane-3,17-diol↗
PubMed2002

Induction of apoptosis and modulation of activation and effector function in T cells by immunosuppressive drugs.

Immunosuppressive drugs (ISD) are used for the prevention and treatment of graft rejection, graft-versus-host-disease (GVHD) and autoimmune disorders. The precise mechanisms by which ISD interfere with T cell activation and effector function or delete antigen-specific T cells are defined only partially. We analysed commonly used ISD such as dexamethasone (DEX), mycophenolic acid (MPA), FK506, cyclosporin A (CsA), rapamycin (RAP), methotrexate (MTX) and cyclophosphamide (CP) for apoptosis-induction and modulation of activation and effector function in human peripheral T cells, cytotoxic T cell lines (CTL) and Jurkat T cells. Of all drugs tested only CP and MTX prevented antigen-specific proliferation of T cells and decreased cytotoxicity of alloantigen specific CTL lines by direct induction of apoptosis. MTX and CP also slightly increased activation-induced cell death (AICD) and CD95-sensitivity. In contrast, all other drugs tested did not induce T cell apoptosis, increase CD95-sensitivity or AICD. CsA and FK506 even prevented AICD by down-modulation of CD95L. DEX, MPA, CsA, FK506 and RAP inhibited activation of naive T cells, but were not able to block proliferation of activated T cells nor decrease cytotoxic capacity of CTL lines. These results show that ISD can be classified according to their action on apoptosis-induction and inhibition of proliferation and would favour a rational combination therapy to delete existing reactive T cells and prevent further T cell activation.

Apoptosis↗
PubMed2001

Activation of apoptosis pathways in peripheral blood lymphocytes by in vivo chemotherapy.

In addition to myelosuppression, anticancer drugs cause rapid and persistent depletion of lymphocytes, possibly by direct apoptosis induction in mature T and B cells. Induction of apoptosis regulators was analyzed in peripheral blood lymphocytes from pediatric patients undergoing first-cycle chemotherapy for solid tumors. In vivo chemotherapy induced a significant increase in lymphocyte apoptosis ex vivo. The activation of initiator caspase-8 and effector caspase-3 and the cleavage of caspase substrates was detected 12 to 48 hours after the onset of therapy. Caspase inhibition by Z-VAD-fmk did not reduce ex vivo lymphocyte apoptosis in all patients, indicating the additional involvement of caspase-independent cell death. No evidence for the involvement of activation-induced cell death was found in the acute phase of lymphocyte depletion as analyzed by activation marker expression and sensitivity for CD95 signaling. Lymphocyte apoptosis in vivo appeared to be predominantly mediated by the mitochondrial pathway because a marked decrease of mitochondrial membrane potential (DeltaPsi(M)) was detected after 24 to 72 hours of treatment, preceded by the increased expression of Bax. Interestingly, despite the use of DNA-damaging agents, p53 remained completely undetectable throughout treatment. In contrast, in vitro treatment with cytarabine and etoposide induced p53 protein, CD95 receptor expression, CD95 sensitivity, and CD95 receptor-ligand interaction in stimulated cycling lymphocytes, but no such induction was seen in resting cells. These data suggest that chemotherapy-induced lymphocyte depletion involves distinct mechanisms of apoptosis induction, such as direct mitochondrial and caspase-dependent pathways in resting cells and p53-dependent pathways in cycling lymphocytes.

Adolescent↗
PubMed2001

Administration of antiprogestin J956 for contraception in bears: a pharmacological study.

Effective and reversible control of reproduction in bears is highly desirable for conservation and management programs in zoos to establish genetically variable ex-situ populations of bears within the constraints of limited space in captivity. The reproductive physiology of bears is characterized by two main traits--seasonality and delayed implantation, which is progesterone dependent. This offers the opportunity to interrupt early pregnancy by short-term administration of antiprogestins. The aim of the present study was to investigate the pharmacological characteristics of antiprogestin J956 to establish an efficient contraceptive protocol for administration of J956 in captive bears. The J956 binds to the uterine progesterone receptor of bears (n = 2) with almost the same relative binding affinity (1.25) as progesterone. The blood serum level of J956 after oral (on four consecutive days) and single parenteral administration was determined by a modified progestin receptor assay. The relative bioavailability of J956 after oral administration was approximately 10% of the parenteral administration. The estimated half-life was 12 to 16 hours after oral administration. Parenteral treatment of J956 (10 mg/kg body mass) led to sustain plasma concentrations (6.4 +/- 1.3 ng/mL) in one black bear and in five brown bears. The plasma level lasted for almost 2 months. Oral and low dosage parenteral (1 mg/kg body mass) administration of J956 had no effect on ongoing pregnancies in bears. Whereas single parenteral administration with higher dosages of J956 (7.5 to 10 mg/kg body mass) efficiently prevented implantation of early embryos in eight female captive bears.

Administration, Oral↗
PubMed2001

c-mpl mutations are the cause of congenital amegakaryocytic thrombocytopenia.

Congenital amegakaryocytic thrombocytopenia (CAMT) is a rare disease presenting with isolated thrombocytopenia in infancy and developing into a pancytopenia in later childhood. Thrombopoietin (TPO) is the main regulator of thrombocytopoiesis and has also been demonstrated to be an important factor in early hematopoiesis. We analyzed 9 patients with CAMT for defects in TPO production and reactivity. We found high levels of TPO in the sera of all patients. However, platelets and hematopoietic progenitor cells of patients with CAMT did not show any reactivity to TPO, as measured by testing TPO-synergism to adenosine diphosphate in platelet activation or by megakaryocyte colony assays. Flow cytometric analysis revealed absent surface expression of the TPO receptor c-Mpl in 3 of 3 patients. Sequence analysis of the c-mpl gene revealed point mutations in 8 of 8 patients: We found frameshift or nonsense mutations that are predicted to result in a complete loss of c-Mpl function in 5 patients. Heterozygous or homozygous missense mutations predicted to lead to amino acid exchanges in the extracellular domain of the receptor were found in 3 other patients. The type of mutations correlated with the clinical course of the disease. We propose a defective c-Mpl expression due to c-mpl mutations as the cause for thrombocytopenia and progression into pancytopenia seen in patients with CAMT.

Adenosine Diphosphate↗
PubMed2001

Gemcitabine and vinorelbine in patients with advanced lung cancer: preclinical studies and report of a phase I trial.

PURPOSE: This study was designed to assess the efficacy of gemcitabine plus vinorelbine using the mouse Lewis lung carcinoma model and to translate this regimen to a phase I clinical study of these two agents in patients with advanced lung cancer. MATERIALS AND METHODS: Using the mouse Lewis lung cancer model, employing growth delay and isobologram analysis, we demonstrated that gemcitabine, in combination with vinorelbine, produced additive activity with little increased toxicity over a wide range of doses. At the highest dose level studied, antagonism was observed. Based on these results, we initiated a phase IGemcitabine and vinorelbine in patients with advanced lung cancer: preclinical studies and report of a phase I trial study of this combination at the Dana Farber Cancer Institute (DFCI) in patients with untreated or once pretreated non-small-cell lung cancer (NSCLC) or once pretreated small-cell lung cancer (SCLC). Vinorelbine (given in an intravenous bolus) and gemcitabine (given in a 30-min infusion) were initially administered to patients at a dose of 15 mg/m2 and 500 mg/m2, respectively, on days 1, 8, and 15 of a 28-day cycle. Seven dose levels were subsequently explored over the course of the study. There was no intrapatient dose escalation. RESULTS: From November 1996 to March 1998, 40 patients were enrolled: 32 had NSCLC, 5 had SCLC and 3 had mixed disease (both SCLC and NSCLC). The patients were evenly divided by gender, the median age was 58 years (range 38 to 73 years), and the median ECOG performance status was 1 (range 0 to 2). All patients had normal renal and hepatic function and none had previously received gemcitabine or vinorelbine. Toxic reactions included mild to moderate fatigue, nausea, constipation, and, most significantly, neutropenia and thrombocytopenia. Phlebitis was a major problem when central venous lines were not used with 15% grade 1/2 events. The day-15 dose was held in 43% of patients at the expanded dose. No true maximum tolerated dose was reached after completion of seven dose levels. Dose level 4 (22.5 mg/m2 vinorelbine and 1,000 mg/m2 gemcitabine) was chosen for expansion and future study due to the potential increased ability of patients to receive the full doses on time. CONCLUSIONS: We conclude that this drug combination and dosage are feasible and have potential as either a front- or second-line chemotherapeutic regimen for advanced lung cancer, and phase II/III trials should be performed. However, hematologic toxicities, as found in this study, could probably be reduced with treatment on days 1 and 8 every 21 days, and current literature would suggest this to be the preferred schedule.

Adult↗
PubMed2001

Use of recombinant factor VIIa (NovoSeven) in patients with Glanzmann thrombasthenia.

Recombinant factor VIIa (rFVIIa; NovoSeven, Novo Nordisk, Bagsvaerd, Denmark) appears effective and relatively safe for the treatment of bleeding and for surgical prophylaxis in patients with Glanzmann thrombasthenia as reported to the International Registry on rFVIIa and Congenital Platelet Disorders. One of the shortcomings of the Registry data is the heterogeneity of treatment protocol, including dosage, number of doses used, duration of treatment before declaration of failure, and mode of rFVIIa administration (bolus v continuous infusion). The data are not yet sufficient to define optimal regimens for various indications such as the type of bleeding or the type of procedures. The place of this drug compared to platelet transfusion in the overall management of patients with Glanzmann thrombasthenia will need to be determined in relationship to a number of challenges and unresolved issues in the clinical care of these patients. These issues include: how to improve local measures for patients with mucosal bleeds, optimal management of young women during menarche, optimal platelet transfusion regimens for various indications, the relationship between antiplatelet antibodies detected by monoclonal antibody-specific immobilization of platelet antigens (MAIPA) and effectiveness of platelet transfusion, whether there are other biological tests that may correlate with effectiveness of platelet transfusion, and management of pregnancy and delivery regarding antiplatelet immunization.

Coagulants↗
PubMed2000

Could chest X-ray screening for lung cancer be cost-effective?

BACKGROUND: Currently, no screening program for lung cancer is advocated, yet recent review of the clinical trials has raised questions about the conclusion that it would not be effective. If a screening program is to be considered, its potential economic impact needs to be assessed. METHODS: An economic model was created comparing lung cancer mortality in male smokers ages 45-80 years, screened versus unscreened. Estimates of the potential reduction in mortality and cost of screening are applied. The outcomes of the model include deaths avoided, life years gained, net costs, and cost-effectiveness. RESULTS: The base analysis (mortality reduction of 18%) estimates that nearly 3000 deaths would be avoided in a population of 100,000 male smokers age 40-80 years, at a cost-effectiveness of $9000 per undiscounted life year gained. A program resulting in only 6% mortality reduction would increase the ratio to $25,000 per undiscounted life years gained. CONCLUSIONS: If further examination of lung cancer screening supports its effectiveness, the results of this model suggest that implementation would be economically efficient.

Adult↗
PubMed2000

Treatment of human B cell lymphoma xenografts with a CD3 x CD19 diabody and T cells.

The use of anti-CD3 x antitumor bispecific Abs is an attractive and highly specific approach in cancer therapy. Recombinant Ab technology now provides powerful tools to enhance the potency of such immunotherapeutic constructs. We designed a heterodimeric diabody specific for human CD19 on B cells and CD3epsilon chain of the TCR complex. After production in Escherichia coli and purification, we analyzed its affinity, stability, and pharmacokinetics, and tested its capacity to stimulate T cell proliferation and mediate in vitro lysis of CD19+ tumor cells. The effect of the diabody on tumor growth was investigated in an in vivo model using immunodeficient mice bearing a human B cell lymphoma. The CD3 x CD19 diabody specifically interacted with both CD3- and CD19-positive cells, was able to stimulate T cell proliferation in the presence of tumor cells, and induced the lysis of CD19+ cells in the presence of activated human PBL. The lytic potential of the diabody was enhanced in the presence of an anti-CD28 mAb. In vivo experiments indicated a higher stability and longer blood retention of diabodies compared with single chain Fv fragments. Treatment of immunodeficient mice bearing B lymphoma xenografts with the diabody and preactivated human PBL efficiently inhibited tumor growth. The survival time was further prolonged by including the anti-CD28 mAb. The CD3 x CD19 diabody is a powerful tool that should facilitate the immunotherapy of minimal residual disease in patients with B cell leukemias and malignant lymphomas.

Animals↗
PubMed2000

Functional CD95 ligand and CD95 death-inducing signaling complex in activation-induced cell death and doxorubicin-induced apoptosis in leukemic T cells.

Activation-induced cell death (AICD) in T cells is mediated by CD95 ligand (CD95L)/receptor interaction, which has also been implicated in apoptosis induction by some anticancer agents. In this article we show that both anti-CD3-triggering (AICD) and doxorubicin treatment led to the production of a functionally active CD95L in the CD3+/T-cell receptor-positive (TCR+) T leukemia cell line H9. CD95L-expressing H9 cells killed CD95-sensitive J16 or CEM target cells, but not CD95-resistant CEM or J16 cells overexpressing dominant negative FADD (J16/FADD-DN). By immunoprecipitation, CD95L was physically bound to CD95, suggesting that AICD and doxorubicin-induced apoptosis involve CD95L-mediated CD95 aggregation, thereby triggering the CD95 death pathway. CD95 aggregation was associated with the recruitment of FADD and caspase-8 to the CD95 receptor to form the CD95 death-inducing signaling complex (DISC), resulting in caspase-8 activation and cleavage of the effector caspase-3 and PARP. Blocking of the CD95L/receptor interaction by antagonistic antibodies to CD95 or to CD95L also blocked AICD and inhibited the early phase of doxorubicin-induced apoptosis, though cell death induced by doxorubicin eventually proceeded in a CD95-independent manner. These findings may explain some conflicting data on the role of death receptor systems in drug-induced apoptosis. Thus, in cells with an inducible CD95 receptor/ligand system, drug-induced apoptosis may be mediated by CD95L-initiated DISC formation and activation of downstream effector programs similar to AICD in T cells. (Blood. 2000;95:301-308)

Apoptosis↗
PubMed2000

Patient handling with and without slings: an analysis of the risk of injury to the lumbar spine.

Health professionals handling patients are known to be at risk of sustaining work related low back injuries. It is not known whether the use of lifting slings reduces the risk of injury to the lumbar spine for patient handlers. This study used kinematic variables and subjective ratings of body part stress and lifter preference as measures of relative risk for three two-person techniques for carrying a patient from one chair to another chair. The techniques used no slings, one and two slings respectively. Twenty-two nurses performed five trials each of the three techniques. Kinematic measures of angular displacement, velocity and acceleration were obtained using the lumbar motion monitor and visual analogue scales were used to obtain measures of body part stress for seven body parts. Angular displacement, velocity and acceleration were significantly greater (p < 0.05) in the frontal, sagittal and transverse planes for the no sling technique compared to techniques using slings. Comparatively small yet significant differences between techniques using slings were recorded for sagittal flexion and rotation. There was no significant difference between one and two sling techniques for other dependent variables. Mean total body stress rating was higher for the no sling technique and all subjects indicated that their first preference was for slings. Although all three measures of risk rated the no sling technique as carrying a higher level of risk than the techniques using slings. No single measure adequately captured all aspects of relative risk. The elimination of manual patient handling is thought to be the best option for the reduction of work related back injuries in patient handlers. Where resources or technology are not yet adequate to provide practical alternatives and where the use of manual technique for a seat to seat task is unavoidable, the use of patient handling slings will reduce the risk.

Adult↗
PubMed2000

Regional cerebral blood flow autoregulation in patients with fulminant hepatic failure.

The absence of cerebral blood flow autoregulation in patients with fulminant hepatic failure (FHF) implies that changes in arterial pressure directly influence cerebral perfusion. It is assumed that dilatation of cerebral arterioles is responsible for the impaired autoregulation. Recently, frontal blood flow was reported to be lower compared with other brain regions, indicating greater arteriolar tone and perhaps preserved regional cerebral autoregulation. In patients with severe FHF (6 women, 1 man; median age, 46 years; range, 18 to 55 years), we tested the hypothesis that perfusion in the anterior cerebral artery would be less affected by an increase in mean arterial pressure compared with the brain area supplied by the middle cerebral artery. Relative changes in cerebral perfusion were determined by transcranial Doppler-measured mean flow velocity (V(mean)), and resistance was determined by pulsatility index in the anterior and middle cerebral arteries. Cerebral autoregulation was evaluated by concomitant measurements of mean arterial pressure and V(mean) in the anterior and middle cerebral arteries during norepinephrine infusion. Baseline V(mean) was lower in the brain area supplied by the anterior cerebral artery compared with the middle cerebral artery (median, 47 cm/s; range, 21 to 62 cm/s v 70 cm/s; range 43 to 119 cm/s, respectively; P <.05). Also, vascular resistance determined by pulsatility index was greater in the anterior than middle cerebral artery (median, 1.02; range 1.00 to 1.37 v 0.87; range 0.75 to 1.48; P <.01). When arterial pressure was increased from 84 mm Hg (range 57 to 95 mm Hg) to 115 mm Hg (range, 73 to 130 mm Hg) during norepinephrine infusion, V(mean) remained unchanged in 2 patients in the anterior cerebral artery, whereas it increased in the middle cerebral artery in all 7 patients. In the remaining patients, V(mean) increased approximately 25% in both the anterior and middle cerebral arteries. Thus, this study could only partially confirm the hypothesis that autoregulation is preserved in the brain regions supplied by the anterior cerebral artery in patients with FHF. Although the findings of this small study need to be further evaluated, one should consider that autoregulation may be impaired not only in the brain region supplied by the middle cerebral artery, but also in the area corresponding to the anterior cerebral artery.

Adolescent↗
PubMed2000

Cerebral perfusion, cardiac output, and arterial pressure in patients with fulminant hepatic failure.

OBJECTIVE: To evaluate whether changes in cardiac output influence cerebral perfusion directly. In fulminant hepatic failure, the circulation is characterized by wide variations in cardiac output and cerebral blood flow (CBF). DESIGN: A retrospective, interindividual analysis of CBF and cardiac output (part 1) and a prospective evaluation of cerebral perfusion, cardiac output, and arterial pressure during norepinephrine infusion (part 2). SETTING: A four-bed specialist liver failure unit. PATIENTS AND INTERVENTIONS: Twenty patients with fulminant hepatic failure (median age, 43 yrs; range, 17-54; 13 women) maintained on mechanical ventilation (Paco2, 33 torr [4.40 kPa]; range, 26-36 torr [3.47-4.80 kPa) after development of hepatic encephalopathy, stages 3 to 4, had mean arterial pressure (MAP) and cardiac output determined by radial and pulmonary artery catheters. Cerebral perfusion was measured by the 133Xenon clearance technique (n = 8) and by transcranial Doppler sonography, which was used to measure mean flow velocity (Vmean). CBF and Vmean in patients with high cardiac output (>9 L/min) were compared with those with normal or low cardiac output. In the second part of the study, cerebral autoregulation was evaluated by concomitant measurement of Vmean, cardiac output, and MAP during norepinephrine infusion in nine patients. MEASUREMENTS AND MAIN RESULTS: Median cardiac output was 8.5 L/min (range, 3.2-17.3), CBF was 33 mL/100 g/min (12-77 g/min), and Vmean was 45 cm/sec (22-65 cm/sec). In patients with elevated cardiac output, MAP, Vmean, and CBF were similar compared with patients with normal cardiac output. Neither CBF nor Vmean correlated to cardiac output. During norepinephrine infusion, Vmean increased from 49 cm/sec (34-69 cm/sec) to 63 cm/sec (58-90 cm/sec; p < .05), as MAP increased from 75 mm Hg (54-105 mm Hg) to 97 mm Hg (90-128 mm Hg). On average, cardiac output remained unchanged at 5.7 L/min (range, 3.2-17.3), as it increased in five patients and decreased in four patients. The change in Vmean was related to MAP (r2 = .76; p < .01) but not to cardiac output (r2 = .01). CONCLUSION: This study shows that CBF correlates to arterial pressure rather than to cardiac output in patients with fulminant hepatic failure. The presence of pressure-passive cerebral circulation stresses the importance of strict cardiovascular control in securing continuous and sufficient cerebral oxygenation and in avoiding the development of cerebral hyperemia and cerebral edema.

Adolescent↗
PubMed1999

Cerebrovascular metabolic autoregulation is impaired during liver transplantation.

BACKGROUND: We determined whether the coupling between cerebral blood flow (CBF) and oxygen metabolism (CMRO2) is preserved during liver transplantation. Because of cerebrovascular dilatation, we hypothesized that cerebral metabolic autoregulation is impaired, because CBF becomes uncoupled from CMRO2 during the reperfusion phase of the operation. MATERIALS AND METHODS: In a prospective study, 13 patients (8 women, median age 46, range 21-6) with liver failure (10 with end-stage chronic liver disease and 3 with acute liver failure) were enrolled. Catheters were placed in a femoral artery and in the internal jugular vein for calculation of the cerebral arteriovenous oxygen content difference (AVDO2). CBF was recorded by the 133Xenon injection technique, and by transcranial Doppler sonography determined mean flow velocity (Vmean) in the middle cerebral artery. The CMRO2 was calculated as the AVDO2 times CBF and the cerebrovascular resistance (CVR) as the mean arterial pressure to CBF ratio. An index of large cerebral artery diameter was expressed by the CBF to Vmean ratio. RESULTS: From induction of anesthesia to the anhepatic period, CBF decreased from a median of 47 (interquartiles 31-55) to 41 (37-48) ml 100 g(-1) min(-1), whereas the CMRO2 remained unchanged (1.3 [0.9-2.5] vs. 1.7 [0.9-2.3] ml 100 g(-1) min(-1)). In the reperfusion phase, the CBF increased to 51 (45-54) ml 100 g(-1) min(-1), whereas the CMRO2 remained unchanged at 1.1 (1.0-2.5) ml 100 g(-1) min(-1). The CVR decreased from 2.0 mm Hg (1.4-2.1) to 1.4 (1.1-1.8) mm Hg(-1) min 100 g ml. In the anhepatic phase, mean arterial pressure decreased from 92 mm Hg (84-98) to 85 (80-92) mm Hg and at reperfusion it was 80 (71-105) mm Hg. From the anhepatic to the reperfusion phase, the CBF increased 7% (0 to 26) for each mm Hg concomitant increase in PaCO2. The CBF to Vmean ratio remained stable (1.0 [0.8-1.2] vs. 0.9 [0.7-1.1] ml 100 g(-1) min(-1) cm(-1) sec). CONCLUSION: During the reperfusion phase of liver transplantations, cerebrovascular dilatation uncouples cerebral oxidative metabolism from blood flow. The increase in CBF is beyond what can be explained by changes in arterial carbon dioxide tension and arterial pressure.

Adult↗