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S Leucht

Publications and source records attributed to S Leucht.

35 records · Page 2Linked to original sources
PubMed2003

Are patients with schizophrenia under-treated with second-generation antipsychotics? A pilot study of the prescription practices of German psychiatrists.

INTRODUCTION: Patients' and relatives' associations, psychiatrists, and pharmaceutical companies are complaining about a deficiency in the care of psychiatric patients with innovative medications in Germany. They estimate that only about 10- 30 % of all patients with schizophrenia receive second-generation antipsychotics, a figure that lies significantly below the international average. METHODS: In order to determine the frequency of use of second-generation antipsychotics in the actual care of schizophrenic patients, we conducted the following investigations:--Discharge papers of schizophrenic inpatients from a university hospital and from a district hospital were studied with regard to the antipsychotic discharge medication.--Practicing psychiatrists were contacted and asked whether during the first 3 months after discharge they had continued the antipsychotic discharge medication that was proposed by the hospital. RESULTS: The investigation of a total of 200 discharge papers and the subsequent questioning of the psychiatrists who carried out the follow-up treatment showed that 166 patients (83 %) received a second-generation antipsychotic upon discharge. Only 5 % of these patients were switched to conventional antipsychotics in the outpatient treatment. Thus, contrary to our expectations, there was no noteworthy change from second-generation to classical antipsychotics. DISCUSSION: Therefore, in the sample analyzed the second-generation antipsychotics were far more frequently prescribed than would have been expected according to general estimates, and it was not possible to verify the often-heard complaints of an under-treatment with second generations in this study. Our findings suggest, however, that only 60 % of the patients still receive their discharge medication 3 months after discharge from the hospital. This raises the important question as to how continuity of the antipsychotic treatment could be better ensured.

Adult↗
PubMed2002

Perazine for schizophrenia.

BACKGROUND: Perazine is an old phenothiazine derivative used for the treatment of people with schizophrenia which has a reputed low level of extrapyramidal side-effects. However, its use is restricted in the sense that - to the best knowledge of the reviewers - it is only marketed in Germany, Poland, Yugoslavia and the Netherlands. OBJECTIVES: To examine the effects of perazine for those with schizophrenia, and schizophrenia-like psychoses. SEARCH STRATEGY: Electronic searches of the Cochrane Schizophrenia Group's register which includes relevant randomised controlled trials from the bibliographic databases Biological Abstracts, CINAHL, The Cochrane Library, EMBASE, MEDLINE, PsycLIT, LILACS, PSYNDEX, Sociological Abstracts and Sociofile were undertaken. References of all included studies were searched for further trials. Pharmaceutical companies and authors of trials were contacted. SELECTION CRITERIA: All randomised controlled trials that compared perazine with other treatments for people with schizophrenia and/or schizophrenia-like psychoses. DATA COLLECTION AND ANALYSIS: Citations and, where possible, abstracts were independently inspected by two reviewers, papers ordered, re-inspected and quality assessed. Data were independently extracted. Data were excluded if loss to follow up was greater than 50%. For homogeneous dichotomous data the Relative Risk (RR), 95% confidence interval (CI) and, where appropriate, the number needed to treat (NNT) were calculated on an intention-to-treat basis. For continuous data, weighted mean differences were calculated (WMD). All data were inspected for heterogeneity. MAIN RESULTS: Six trials with a total of 288 participants are included. According to only one trial with 95 participants perazine appeared superior to active placebo (trimipramine) at five weeks for the outcome of 'no important global improvement' (n=95, RR 0.6, CI 0.3-0.9, NNT 4, CI 2-17), but there was no difference in various measures of mental state. The side-effect risk of perazine compared to placebo could not be estimated because they were not reported. Five small trials including only 193 participants which compared perazine with other antipsychotics were incompletely reported and the outcomes were presented in various ways so that meta-analysis was not possible in most occasions. A similar number of participants receiving perazine or comparator antipsychotics left the studies early (n=193, RR 0.9, CI 0.5-1.4). The results on efficacy were controversial and need further assessment by randomised controlled trials. No obvious differences in adverse events between perazine and other antipsychotics could be derived from these limited data. Two haloperidol comparisons did not present extrapyramidal side-effects in a way usable for meta-analysis, but three small comparisons with the atypical antipsychotics zotepine and amisulpride showed no higher risk of akathisia (n=111, RR 0.3, CI 0.1-1.1), dyskinesia (n=111, RR 0.5, CI 0.1-3.5), parkinsonism (n=81, RR 1.2, CI 0.5-2.8) or tremor (n=40, RR 0.8, CI 0.3-2.3) with perazine. REVIEWER'S CONCLUSIONS: The number, size and reporting of randomised controlled perazine trials is insufficient to present firm conclusions about the properties of this antipsychotic. It is possible that perazine is associated with a similar risk of extrapyramidal side-effects as some atypical antipsychotics, and this should be clarified in larger, well-designed trials.

Antipsychotic Agents↗
PubMed2002

Benperidol for schizophrenia.

BACKGROUND: Benperidol is a relatively old antipsychotic drug, marketed since 1966, used in Germany for 30 years, but also available in Belgium, Greece, Italy, the Netherlands and the UK. Benperidol is a butyrophenone antipsychotic, with the highest neuroleptic potency in terms of D2 receptor blockade. Those taking it are, therefore, reputed to be at high risk of extrapyramidal side effects, but benperidol's unusual profile may render it of value to subgroups of people with schizophrenia. OBJECTIVES: To examine the clinical effects and safety of benperidol for those with schizophrenia and schizophrenia-like psychoses. SEARCH STRATEGY: The reviewers searched the Cochrane Schizophrenia Group's register (January 2001) which includes relevant randomised controlled trials from the bibliographic databases Biological Abstracts, CINAHL, The Cochrane Library, EMBASE, MEDLINE, PsycLIT, LILACS, PSYNDEX, Sociological Abstracts and Sociofile. We also searched the references of all included studies and contacted pharmaceutical companies and authors of included studies in order to identify further trials. SELECTION CRITERIA: Randomised controlled trials that compared benperidol with other treatments for people with schizophrenia and/or schizophrenia-like psychoses. DATA COLLECTION AND ANALYSIS: Citations and, where possible, abstracts were independently inspected by two reviewers and papers were ordered, re-inspected and quality assessed. We independently extracted data but excluded data if loss to follow up was greater than 50%. For homogeneous dichotomous data, we calculated the relative risk (RR), the 95% confidence interval (CI) and, where appropriate, the number needed to treat/harm (NNT/H), on an intention-to-treat basis. MAIN RESULTS: We identified only one unpublished poorly randomised controlled trial (N=40, duration 30 days, comparison perphenazine). Although benperidol was inferior to perphenazine (1 RCT, N=40, global state no better or worse RR 8.0 CI 2.1 to 30, NNH 1.4 CI 1 to 2) poor reporting suggests that an overestimate of effect is likely. It was not possible to report other outcomes. REVIEWER'S CONCLUSIONS: Currently, there are insufficient data from randomised trials to assess the clinical effects of benperidol. This interesting compound merits further research.

Antipsychotic Agents↗
PubMed2001

The B cell superantigen-like interaction of intravenous immunoglobin (IVIG) with Fab fragments of V(H) 3-23 and 3-30/3-30.5 germline gene origin cloned from a patient with Kawasaki disease is enhanced after IVIG therapy.

The etiology of Kawasaki disease (KD) is still unknown. Therefore, the diagnosis relies on clinical criteria only. Although a specific therapy for KD is not available, coronary complications can be significantly reduced with the help of intravenous immunoglobulin (IVIG) therapy. It is not clear how IVIG interacts with the immune system. Previously, we selected a large number of IgG and IgM Fab fragments specifically reacting with IVIG molecules by phage display and antiidiotypic panning from three patients with autoimmune thrombocytopenia, a patient with lupus, and a healthy individual. Sequencing revealed that the favored V(H) germline gene segments of these IVIG-bound Fabs were 3-23 or 3-30/3-30.5, the most frequently rearranged V(H) genes among human B cells. The binding pattern suggested a B cell superantigen-like, specific interaction of an IVIG subset with B cells that present B cell receptors derived from these two germline genes. The aim of the current study was to investigate whether treatment with IVIG influences this restricted interaction. Therefore we cloned and selected Fab fragments from a patient with KD before and after IVIG therapy. A favored selection of antibodies derived from both the 3-23 and the 3-30/3-30.5 germline gene segments as before was observed. Importantly, the reactivity with IVIG was significantly higher for clones from the library prepared after the IVIG treatment, providing the first in vivo functional evidence that a subset of IVIG may selectively activate B cells of this germline origin. This mechanism may add to the therapeutic effect of IVIG in the treatment of KD.

B-Lymphocytes↗
PubMed2001

Dropout rates in randomised antipsychotic drug trials.

RATIONALE: It has been assumed that new atypical drugs improve treatment compliance due to fewer adverse effects. Data supporting this assumption are scarce. OBJECTIVES: The aim of this study was to study attrition rates in randomised controlled trials of oral administration of conventional antipsychotic drugs, atypical antipsychotic drugs and placebo. METHODS: The database of the Schizophrenia Module of the Cochrane Library was utilised for the present study. The data in the Cochrane Module are collected by identifying relevant randomised controlled trials from several electronic databases and other sources. Number of dropouts was defined as patients leaving the study preterm due to any reason. RESULTS: Data from 328 treatment groups, consisting of 18,585 randomised subjects from 163 drug trials, were entered in the analysis. One-third of the subjects had dropped out of the trials. The dropout rates significantly increased for each calendar year. Year of trial publication, type of drug and trial length remained statistically significant contributors to dropout rates. In a model incorporating year of publication and trial length, placebo groups and groups treated with conventional antipsychotics had significantly higher attrition rates than groups treated with atypical drugs. When clozapine-treated groups were excluded from the analysis, no statistically significant advantage for atypical drugs over conventional drugs remained. CONCLUSIONS: Trial data implicate that a better compliance can be achieved by favouring atypical drugs rather than conventional alternatives in the treatment of schizophrenia. However, this effect is found only when groups treated with the atypical antipsychotic clozapine are included in the analysis. Our study did not find evidence for a statistically significant superiority in acceptability of novel atypical drugs when compared to conventional antipsychotics.

Antipsychotic Agents↗
PubMed2001

Pharmacogenetics: a new diagnostic tool in the management of antidepressive drug therapy.

Pharmacogenetics studies the genetic basis of an individual's ability to respond to pharmacotherapy. Variability of this response is a major problem. Fatal adverse drug reactions have been reported to be the fourth leading cause of death in the US. In depression, 30-40% of all patients do not respond sufficiently to the initial treatment and it can take up to 6 weeks for them to be identified. Much knowledge has been gathered throughout the last 3 decades about the genetic basis of pharmacokinetic variability. Genetic tests suitable for the routine laboratory are now available for some important metabolizing enzymes (e.g., CYP2D6, CYP2C19) identifying those individuals who are slow or fast metabolizers of certain drugs, many of which are widely used in the treatment of depression (e.g., tricyclic antidepressants). The possible use of these tests in the clinical practice of monitoring antidepressant therapy is discussed in relation to older phenotyping methods and therapeutic drug monitoring.Less well studied than the genetics of pharmacokinetics is the genetic basis of pharmacodynamic variability. As selective serotonin reuptake inhibitors (SSRI) have a wide therapeutic index, pharmacokinetic variability usually does not explain insufficient response to therapy. Recently, some excitement was caused by reports on serotonin transporter gene polymorphisms and their influence on the response to antidepressive therapy with SSRIs as this could provide an interesting diagnostic tool in assessing the chances of response to the most popular group of antidepressants at present. Current knowledge in this young field of research is summarized.

Antidepressive Agents↗
PubMed2001

The effect of family interventions on relapse and rehospitalization in schizophrenia--a meta-analysis.

Twenty-five intervention studies were meta-analytically examined regarding the effect of including relatives in schizophrenia treatment. The studies investigated family intervention programs to educate relatives and help them cope better with the patient's illness. The patient's relapse rate, measured by either a significant worsening of symptoms or rehospitalization in the first years after hospitalization, served as the main study criterion. The main result of the meta-analysis was that the relapse rate can be reduced by 20 percent if relatives of schizophrenia patients are included in the treatment. If family interventions continued for longer than 3 months, the effect was particularly marked. Furthermore, different types of comprehensive family interventions have similar results. The bifocal approach, which offers psychosocial support to relatives and schizophrenia patients in addition to medical treatment, was clearly superior to the medication-only standard treatment. The effects of family interventions and comprehensive patient interventions were comparable, but the combination did not yield significantly better results than did a treatment approach, which focused on either the patient or the family. This meta-analysis indicates that psychoeducational interventions are essential to schizophrenia treatment.

Adaptation, Psychological↗
PubMed2001

Doxepin plasma concentrations: is there really a therapeutic range?

Despite the introduction of numerous new agents, tricyclic antidepressants remain an important option for the treatment of depression. Doxepin is still in wide use, and determining its concentration is a standard procedure in many psychiatric clinics. Some widely cited reviews indicate a therapeutic range from 150 to 250 ng/mL (parent plus desmethyl metabolite). The vast majority of the authors' patients fell short of these concentrations under customary doses. To resolve this issue, the authors' serum-level databank was analyzed, a questionnaire was sent to U.S. and German psychiatric university departments and laboratories, and the literature was reviewed. The main results were the following: (1) Only 9% of all samples analyzed (N = 217) displayed plasma levels (high-performance liquid chromatography) between 150 and 250 ng/mL; 88% were subtherapeutic. The mean doxepin + desmethyldoxepin steady-state serum concentration was 89+/-75 ng/mL (N = 32, doxepin >3 weeks). The mean daily dose was 143+/-30 mg. There was no correlation between concentrations and improvement. (2) A wide variety of recommendations is given by the different university departments (10-1,000 ng/mL). (3) According to the studies published to date, there is not enough evidence for recommending a therapeutic range. The preliminary suggestions given in some influential reviews have been widely adopted without critical re-evaluation. Compared with the concentrations found in the original studies, the therapeutic ranges suggested are too high. A methodologically sound study to determine a therapeutic range is required for the rational monitoring of this drug. Meanwhile, a preliminary working range of 50 to 250 ng/mL is proposed on the basis of critical reassessment of published data.

Aged↗
PubMed2000

Carbamazepine for schizophrenia and schizoaffective psychoses.

BACKGROUND: A sizeable minority of people with schizophrenia do not have complete remission of symptoms. A variety of adjunctive treatments have been used to treat schizophrenia, carbamazepine being one. OBJECTIVES: To review the effects of carbamazepine and its derivatives for the treatment of schizophrenia and schizoaffective psychoses. SEARCH STRATEGY: Biological Abstracts (1980-1998), The Cochrane Library (Issue 3, 1998), The Cochrane Schizophrenia Group's Register of Trials (August 1998), EMBASE (1980-1998), MEDLINE (1966-1998), PsycLIT (1886-1998) and PSYNDEX (1974-1998) were searched. Citations from included trials were also inspected and relevant companies and authors contacted for additional data. SELECTION CRITERIA: All randomised controlled trials comparing carbamazepine, or compounds of the carbamazepine family, to placebo or no intervention, whether as sole treatment or as an adjunct to antipsychotic medication for the treatment of schizophrenia and/or schizoaffective psychoses. DATA COLLECTION AND ANALYSIS: Citations and, where possible, abstracts were independently inspected by reviewers, papers ordered, re-inspected and quality assessed. Data were extracted independently by at least two reviewers. Dichotomous data were analysed using Peto odds ratio (OR) and the 95% confidence interval (CI) estimated. Where possible the number needed to treat (NNT) or number needed to harm statistics were calculated. MAIN RESULTS: There is no clear effect of carbamazepine as the sole maintenance treatment for those with schizophrenia. Eight trials provided very limited data on the value of carbamazepine as an adjunct to antipsychotics. Studies were small and poorly reported. Currently no published data provides convincing evidence that adjunctive carbamazepine has an effect on global functioning, mental state, side effects or acceptability of treatment. REVIEWER'S CONCLUSIONS: Based on currently available randomised trial-derived evidence, carbamazepine cannot be recommend for routine clinical use for treatment or augmentation of antipsychotic treatment of schizophrenia. However, for those with a past history of being responsive to carbamazepine, or for those with associated EEG abnormalities, a trial of the drug may be warranted. More data is expected from trialists and the results of this review may be changed by their inclusion. At present large, simple well designed and reported trials are justified especially if focusing on those with both schizophrenia and EEG abnormalities or violent episodes and people with schizoaffective disorders.

Antimanic Agents↗
PubMed2000

Effect of adjunctive paroxetine on serum levels and side-effects of tricyclic antidepressants in depressive inpatients.

RATIONALE: Previous studies showed that adjunctive paroxetine increases tricyclic antidepressant (TCA) serum levels by inhibiting cytochrome P4502D6. This effect has, however, been examined only in experimental studies using low doses of TCAs in healthy volunteers. OBJECTIVE: The present study investigated TCA serum level changes and side-effects after the addition of paroxetine in depressed patients treated with doses customarily used for inpatients. METHODS: 14 patients who had a moderate or severe depressive episode according to ICD-10 and who had not sufficiently responded (< or = 25% reduction of the Hamilton depression scale) to 3-week monotherapy with amitriptyline (n = 9) or imipramine (n = 5) with daily doses between 125 and 200 mg/day, received 20 mg/day paroxetine additionally under steady state conditions. RESULTS: After 2 weeks the serum levels of the metabolites nortriptyline (from 88 +/- 49 ng/ml to 176 +/- 57 ng/ml) and desipramine (from 152 +/- 78 ng/ml to 338 +/- 104 ng/ml) had risen to a significantly greater extent than those of the parent compounds amitriptyline (123 +/- 50 ng/ml to 195 +/- 128 ng/ml) and imipramine (from 75 +/- 36 ng/ml to 98 +/- 51 ng/ml). It is noteworthy that, with the exception of one case of incipient delirium, the combination therapy was well tolerated despite high TCA serum level rises. CONCLUSION: The higher increase of the metabolites as compared with the parent compounds can be explained by a paroxetine-induced inhibition of the liver enzyme cytochrome P4502D6, which catalyses the second step of the TCA metabolism, i.e. the hydroxylation of the metabolites. Blood levels should be meticulously monitored, if TCAs are combined with paroxetine.

Antidepressive Agents, Second-Generation↗
PubMed1999

Efficacy and extrapyramidal side-effects of the new antipsychotics olanzapine, quetiapine, risperidone, and sertindole compared to conventional antipsychotics and placebo. A meta-analysis of randomized controlled trials.

The objective of this meta-analysis is to summarize the efficacy and tolerability of the new antipsychotics risperidone, olanzapine, sertindole and quetiapine in schizophrenia compared to placebo and conventional antipsychotics. The main results are: (1) All of the 4 new drugs are more effective than placebo, but the magnitude of the effect is only moderate [mean effect size, r, of all antipsychotics vs. placebo = 0.25, with a 95% confidence interval (CI) = 0.22-0.28, n = 2477]. (2) According to the studies published to date, sertindole and quetiapine are as effective as haloperidol, and risperidone and olanzapine are slightly more effective than haloperidol in the treatment of global schizophrenic symptomatology. (3) With respect to negative symptoms, all new antipsychotics are more effective than placebo. However, contrary to widespread opinion, so is the 'conventional' antipsychotic haloperidol. Risperidone and olanzapine are slightly superior, sertindole is as effective and--according to the only study fully published to date--quetiapine is even slightly less effective than haloperidol in this regard. (4) All new antipsychotics are associated with less frequent use of antiparkinson medication than haloperidol, with risperidone appearing to have a slightly less favourable EPS-profile than the other new antipsychotics. The methodological limitations of this review, the generalizability of the results and expectations from future research are discussed.

Antipsychotic Agents↗
PubMed1999

Results of treatment of schizophrenia: is the glass half full or half empty?

On the basis of data from naturalistic studies it is shown that the actual outcome in schizophrenia is by far not as good as it could be. Thus, for example, the relapse rates of schizophrenic patients lie 200% above the value that could actually be achieved according to today's state of knowledge. This results in extra costs of several billion dollars each year. The causes of this great discrepancy between possible and actual outcome are hardly known, since psychiatric researchers have previously not been very interested in the outcome of normal care patients. But patients, carers and fund holders expect that psychiatrists should rapidly close the gap between the actual and the possible outcome. They will succeed only if psychiatric researchers become more interested in the normal care situation, perform more naturalistic studies, more compliance research, and more studies into medical decision making.

Evidence-Based Medicine↗
PubMed1997

Variability of cerebral blood flow deficits in 99mTc-HMPAO SPECT in patients with Alzheimer's disease.

The purpose of this study was to analyse the frequency of the different pathological perfusion patterns in SPECT in a clinical, unselected population of patients with Alzheimer's disease. In 91 patients and 16 control subjects regional cerebral blood flow (rCBF) was measured with Single Photon Emission Computed Tomography (SPECT) using 99mTc-hexa-methyl-propyleneamine oxime (HMPAO). 95% confidence intervals obtained from the perfusion values of the control subjects were used to define normal perfusion ranges. The frequency of perfusion deficits in the left frontal, temporal, parietal and occipital lobes were 62.2%, 60.4%. 70.3% and 23.1%, respectively. In the right hemisphere the corresponding values were 60.4%, 58.2%, 63.7% and 9.9%. With the exception of the occipital lobes these frequencies were not significantly different. The analysis of the perfusion pattern of each patient revealed 35 different combinations of lobes with perfusion deficits. The temporo-parietal perfusion deficits were not more frequent than the temporofrontal perfusion deficits. These results suggest that in the clinical routine a high variety of heterogeneous rCBF patterns have to be expected.

Aged↗
PubMed1997

[Are negative cognitions symptoms of depression or also an expression of personality traits?].

This study examined the changes from hospital admission to discharge of different categories of cognitive distortions - automatic thoughts, self-concepts and dysfunctional attitudes - in 67 patients with an ICD-10 diagnosis of a depressive episode. Furthermore, the relationships were analyzed between cognitive distortions, degree of depression, and personality dimensions (isolation tendency, extraversion, rigidity, schizoidia, frustration tolerance and neuroticism). There was a significant correlation between automatic thoughts and negative self-concepts on the one hand, and severity of depression on the other upon admission. There was a significant reduction of automatic thoughts and the negativity of self-concepts from admission to discharge. No significant association was observed, however, between the severity of depression and dysfunctional attitudes. In addition, dysfunctional attitudes showed a significant decrease until discharge only in patients with a full remission of depressive symptoms. These results underline the fact that automatic thoughts and self-concepts are more state-dependent than dysfunctional attitudes. Moreover - even taking into account the degree of depression - there was a significant relationship between the personality dimension neuroticism and all cognitive scales upon admission. This indicates that a high degree of neuroticism may facilitate the emergence of negative cognitions during a depressive episode.

Adult↗
PubMed1995

Accuracy and reproducibility of the measurement of actively circulating blood volume with an integrated fiberoptic monitoring system.

OBJECTIVE: Bedside monitoring of circulating blood volume has become possible with the introduction of an integrated fiberoptic monitoring system that calculates blood volume from the changes in blood concentration of indocyanine green dye 4 mins after injection. The aim of this investigation was to compare the blood volume estimate of the integrated fiberoptic monitoring system (group 1) with the standard methods of blood volume measurement using Evans blue (group 2), and indocyanine green measured photometrically (group 3). DESIGN: Prospective laboratory study. SETTING: Animal laboratory of a University's institute for experimental surgery. SUBJECTS: Eleven anesthetized, paralyzed, and mechanically ventilated piglets. INTERVENTIONS: A central venous catheter was used for the injection of the indicator dyes (Evans blue and indocyanine green). A fiberoptic thermistor catheter was advanced into the thoracic aorta. The fiberoptic catheter detects indocyanine green by reflection densitometry for the estimation of blood volume of the integrated fiberoptic monitoring system. Samples for the determination of Evans blue and indocyanine green concentrations were drawn from an arterial catheter in the femoral artery over a period of 17 mins after injection. MEASUREMENTS AND MAIN RESULTS: Measurements were performed during normovolemia, hypovolemia (blood withdrawal of < or = 30 mL/kg), and hypervolemia (retransfusion of the withdrawn blood plus an infusion of 10% hydroxyethyl starch [45 mL/kg]). Linear regression, correlation, and bias were calculated for the comparison of the blood volume estimates by the fiberoptic monitoring system (group 1) vs. the total blood volume estimates using Evans blue (group 2) and indocyanine green (group 3): group 1 = 0.82.group 2-26 mL; r2 = 82.71%; r = .91; n = 40; group 1-group 2 +/- 1 SD = -435 +/- 368 mL; group 1 = 0.79.group 3 + 50 mL; r2 = 74.81%; r = .87; n = 28; group 1-group 3 +/- 1 SD = -506 +/- 374 mL. CONCLUSIONS: The results demonstrate that the blood volume estimate of the fiberoptic monitoring system (group 1) correlates closely with the total blood volume measurement using Evans blue (group 2) and indocyanine green (group 3). Trapped indicator in the packed red cell column after centrifugation of the blood samples may account for an overestimation of group 2 and group 3 of approximately 10% to 14%, but there still remains a proportional difference of 10% between group 1 vs. group 2 and vs. group 3. This difference is due to the longer mixing times of group 3 (16 mins) and group 2 (17 mins), during which they are distributed in slowly exchanging blood pools. It seems that the blood volume estimate of the fiberoptic monitoring system (group 1) represents the actively circulating blood volume and may be useful for bedside monitoring.

Animals↗
PubMed1994

Monitoring of right ventricular function using a conventional slow response thermistor catheter.

OBJECTIVE: To investigate whether determination of right ventricular end-diastolic volume (RVEDV) and right ventricular ejection fraction (RVEF) can be performed with reasonable accuracy and reproducibility using a conventional slow response thermistor pulmonary artery catheter (CPAC) applying an adaptive algorithm. DESIGN: To study RVEDV and RVEF simultaneously with pulmonary artery catheters equipped with slow and fast response thermistors (FRPAC) under a broad range of cardiac output. SETTING: Laboratory of Institute of Experimental Surgery, Technical University. ANIMALS: 11 anaesthetised piglets. INTERVENTIONS: Hypovolemia (V-) was induced by withdrawal of blood up to 50 ml/kg, hypervolemia (V+) was produced by retransfusing blood and adding up to 30 mg/kg hydroxyethyl starch. In 5 animals in phases V- and V+ beta-adrenergic stimulation was achieved with dobutamine. Finally pulmonary artery hypertension was induced by infusion of small air bubbles. MEASUREMENTS AND RESULTS: Cardiac output (CO), RVEDV and RVEF were determined simultaneously with FRPAC and CPAC placed in the same pulmonary artery branch. Measurements were repeated 8 times sequentially in steady state normovolemia. A total of 130 measurements could be analysed. The coefficient of variation was 6.7 +/- 4.2% for CO(FRPAC) and 4.6 +/- 1.7% for CO(CPAC); for RVEF it was 9.7 +/- 6.2% (FRPAC) and 9.9 +/- 3.9% (CPAC); for RVEDV it was 11.6 +/- 4.8% (FRPAC) and 8.54 +/- 3.2 (CPAC). Mean difference (bias) was 0.06 +/- 0.39 l/min for CO measured with both methods, 19 +/- 35 ml for RVEDV and -3.3 +/- 6.5% for RVEF. CO(CPAC) displayed a strong correlation to CO(FRPAC) (R = 0.97, p = 0.001) as well as RVEF (R for RVEF(CPAC) versus RVEF(FRPAC) = 0.90, p = 0.001). R for RVEDV(CPAC) versus RVEDV(FRPAC) was 0.67, p = 0.001. We conclude that this animal study demonstrates good agreement between RVEF and RVEDV obtained with catheters equipped with a fast response thermistor or with a conventional slow response thermistor allowing accurate monitoring of right ventricular function with a conventional pulmonary artery catheter.

Algorithms↗