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T Stimpfl

Publications and source records attributed to T Stimpfl.

14 recordsLinked to original sources
PubMed2002

[Fatal poisonings with antidepressive drugs and neuroleptics. Analysis of a correlation with prescriptions in Vienna 1991 to 1997].

As a result of the increasing use of selective serotonin reuptake inhibitors (SSRI), the number of antidepressants (AD) prescribed in Vienna doubled from 1991 to 1997. In the same period, autopsies and chemical analyses performed at the Institute of Forensic Medicine, University of Vienna, revealed a total of 164 fatal intoxications by means of AD. In this study, the number of fatal intoxications per million defined daily doses prescribed was determined and referred to as the fatal toxicity index (f-index). For both single- and multiple-substance intoxications, it proved to be significantly (p < 0.001) lower with SSRI than with tricyclic antidepressants (TCA). Single-substance intoxications (n = 30) were seen exclusively in TCA. Concerning neuroleptics (NL), the increase in prescriptions observed in the study period (plus 30%) was less pronounced, and they were found to be involved in 85 fatal intoxications. Also in NL, those of the tricyclic type (TCNL) showed a significantly (p < 0.001) higher f-index than other groups. Out of a total of 17 single-substance intoxications, 14 were caused by TCNL and none by butyrophenones or haloperidol. The present study demonstrates that the prescription of TCA or TCNL involves a relatively high risk of fatal intoxication.

Antidepressive Agents↗
PubMed2001

Different fatal toxicity of neuroleptics identified by autopsy.

Autopsies and toxicological analyses at the Institute of Forensic Medicine revealed 85 fatal intoxications with neuroleptics in Vienna from 1991 to 1997. A total of 17 cases were linked to a single neuroleptic (NL) alone, while 68 deaths were attributed to a combination of NLs with other drugs. The most frequently detected agent was prothipendyl (n=41). During the study period the number of defined daily doses of high-potency NLs prescribed increased significantly (P< or =0.001) due to increased prescribing of new atypical antipsychotics. The quantity of intermediate- and low-potency NLs dispensed remained stable. The most frequently prescribed NL was haloperidol. The relative toxicities of different NLs were calculated by dividing the number of deaths caused by this NL into the number of defined daily doses prescribed in the observation period (f-value). Single-substance intoxications and multiple-substance intoxications were distinguished. The highest f-values were associated with low-potency NLs, especially with prothipendyl, chlorprothixene and levomepromazine. Low f-values were found for the group of high-potency NLs, including flupentixol, fluphenazine, haloperidol and pimozide, as well as olanzapine. Compared to the f-values for all NLs prescribed, f-values for low-potency NLs were shown to be significantly higher concerning single-substance intoxications (P< or = 0.05) and multiple-substance intoxications (P < or = 0.001), while f-values for high-potency NLs were significantly lower (P< or = 0.05 and P< or = 0.001). We are not aware of the psychiatric diagnoses in our post-mortem sample. However, the present results indicate that careless use of low-potent NLs should be avoided in patients with a potential risk of accidental or suicidal overdose.

Adult↗
PubMed2001

General unknown screening in postmortem tissue and blood samples: a semi-automatic solid-phase extraction using polystyrene resins followed by liquid-liquid extraction.

The identification of general unknown poisons in complex biological materials like postmortem blood and tissue is a great challenge for the forensic toxicologist. Therefore, a screening procedure utilizing a semi-automatic work-up with an ASPEC system was developed. A broad range of different compounds can be isolated by using non-selective and generally applicable organic polymeric sorbents such as OASIS HLB or Isolute 101. Because colloidal solutions were applied to these sorbents, the denaturation of proteins, which can result in an irreversible loss of significant compounds by adsorption and occlusion, could be avoided. Because of the process of micellar chromatography followed by liquid-liquid extraction of the crude extract, very clean fractions were obtained from such complex matrices as postmortem blood, liver, and brain samples. High recoveries (72-100%) and good day-to-day relative standard deviations (1-17%) could be achieved with both polymeric sorbents. The procedure paves the way for the identification of general unknown poisons in target organs and is therefore a useful tool in the field of forensic toxicology.

Adsorption↗
PubMed2001

Direct current auditory evoked potentials during wakefulness, anesthesia, and emergence from anesthesia.

Direct current auditory evoked potentials (DC-AEPs) are a sensitive indicator of depth of anesthesia in animals. However, they have never been investigated in humans. To assess the potential usefulness of DC-AEPs as an indicator of anesthesia in humans, we performed an explorative study in which DC-AEPs were recorded during propofol and methohexital anesthesia in humans. DC-AEPs were recorded via 22 scalp electrodes in 19 volunteers randomly assigned to receive either propofol or methohexital. DC-AEPs were evoked by binaurally presented 2-s, 60-dB, 800-Hz tones; measurements were taken during awake baseline, anesthesia, and emergence. Statistical analysis included analysis of variance and discriminant analysis of data acquired during these three conditions. About 500 ms after stimulus presentation, DC-AEPs could be observed. These potentials were present only during baseline and emergence-not during anesthesia. Statistically significant differences were found between baseline and anesthesia and between anesthesia and emergence. In conclusion, similar effects, as reported in animal studies of anesthetics on the DC-AEPs, could be observed in anesthetized humans. These results demonstrate that DC-AEPs are potentially useful in the assessment of cortical function during anesthesia and might qualify the method for monitoring anesthesia in humans.

Adult↗
PubMed2001

Estrogen increases endothelial carbon monoxide, heme oxygenase 2, and carbon monoxide-derived cGMP by a receptor-mediated system.

Carbon monoxide, a gaseous activator of soluble guanylyl cyclase formed by a subtype of the enzyme heme oxygenase designated heme oxygenase-2 in vascular endothelium, has been found to dilate blood vessels independently from nitric oxide. Because of the parallels between nitric oxide and carbon monoxide, we speculated that estrogen might affect carbon monoxide production in vascular endothelium. Endothelial cells of human origin (umbilical vein and uterine artery) were incubated for 4 or 24 h with 10(-12)-10(-6) M 17beta-estradiol. 17beta-Estradiol, at a concentration such as that attained during the ovulatory phase of the menstrual cycle (10(-10) M), administrated for 4 h led to a 2-fold increase in intracellular carbon monoxide production and heme oxygenase-2 protein levels (P < 0.05). A reporter assay, measuring the formation of cGMP as the direct product of carbon monoxide-induced activation of soluble guanylyl cyclase in endothelial cells, also revealed a 56% increase in cellular cGMP after treatment with 10(-10) M E2 17beta-estradiol (P < 0.05). By contrast, higher 17beta-estradiol concentrations had no significant respective effects due to nitric oxide synthase inhibition of carbon monoxide release. This 17beta-estradiol effect appeared to be ER dependent, as preincubation with tamoxifen (10(-6) M) blocked the stimulatory effect of 17beta-estradiol in each instance. Our preliminary data indicate a potential role for carbon monoxide as a biological messenger molecule in estrogen-mediated regulation of vascular tone.

Arteries↗
PubMed2000

[Fatal methadone poisoning of a child].

The substance methadone is used for substitution therapy since the 1960s in the U.S. Mainly because of the endemic spread of HIV-1 infections among intravenous drug abusers methadone was made legally available through medical prescription in Austria in 1987. Legal authorities today also allow the patient to take home the necessary daily consumption for weekends or public holidays. The drug is distributed as a watery solution in tiny bottles, which are fitted with an ordinary screw cap. This kind of distribution may, however, have fatal consequences. This is demonstrated in the following case of accidental poisoning of an infant: A two-year-old girl whose parents were both participating in the substitution scheme was found dead in her bed in Vienna in 1997. Forensic autopsy revealed a methadone concentration in the liver tissue of 640 ng/g. The criminal investigation determined that the girl had opened a bottle of methadone solution and subsequently had taken the drug. Considering the circumstances of this accident, from the medical point of view safety devices for the screw caps of the methadone bottles should be required by law, in order to avoid future accidental poisoning.

Accidents, Home↗
PubMed2000

Suicide by antidepressant intoxication identified at autopsy in Vienna from 1991-1997: the favourable consequences of the increasing use of SSRIs.

In the area of Vienna, any person dying under questionable circumstances is examined at the Institute of Forensic Medicine, where the cause of death is determined by means of autopsy and chemical analysis. Our study on fatal intoxications was performed in the period between 1991 and 1997, when selective serotonin reuptake inhibitors (SSRIs) were establishing themselves on the market, reaching the top of prescription statistics. Tricyclic antidepressants (TCAs) were involved in 30 single- and 127 multiple-substance intoxications, with amitriptyline and doxepin being the most frequently used drugs. SSRIs were involved in five multiple-substance intoxications. The f-value, which refers to the number of deaths per million defined daily doses prescribed, was found to be significantly (P</=0.001) higher in TCAs than in SSRIs. The f-value for the total group of all antidepressants declined significantly (P</=0.05) during the observation period of 7 years. In conclusion, SSRIs turned out to be less toxic than TCAs, and the increasing use of new antidepressants did not coincide with an increased number of deaths caused by these drugs.

Antidepressive Agents↗
PubMed1999

Successful resuscitation of a verapamil-intoxicated patient with percutaneous cardiopulmonary bypass.

OBJECTIVE: To describe our experience with the use of percutaneous cardiopulmonary bypass as a therapy for cardiac arrest in an adult patient intoxicated with verapamil. DESIGN: Case report. SETTING: Emergency department of a university hospital. PATIENT: A patient with cardiac arrest after severe verapamil intoxication. INTERVENTIONS: Percutaneous cardiopulmonary bypass and theophylline therapy. CASE REPORT: A 41-yr-old white male had taken 4800-6400 mg of verapamil in a suicide attempt. On arrival of the ambulance physician, the patient was conscious with weak palpable pulses and was transported to a nearby hospital. The patient developed a pulseless electrical activity, and cardiopulmonary resuscitation was started. Despite all advanced life support efforts, the patient remained in cardiac arrest. Therefore, he was transferred under ongoing cardiopulmonary resuscitation to our department, where percutaneous cardiopulmonary bypass was initiated immediately (2.5 hrs after cardiac arrest). The first verapamil serum concentration obtained at admittance to our institution was 630 ng/mL. After several ineffective intravenous epinephrine applications, the administration of 0.48 g of theophylline as an intravenous bolus 6 hrs and 18 mins after cardiac arrest led to the return of spontaneous circulation. The patient remained stable and was transferred to an intensive care unit the same day. He woke up on the 12th day and was extubated on the 18th day. After transfer to a neuropsychiatric rehabilitation hospital, he recovered totally. CONCLUSION: In patients with cardiac arrest attributable to massive verapamil overdose, percutaneous extracorporeal cardiopulmonary bypass can provide adequate tissue perfusion and sufficient cerebral oxygen supply until the drug level is reduced and restoration of spontaneous circulation can be achieved.

Adult↗
PubMed1998

Drugs and driving in Vienna, Austria.

Drugs that affect the central nervous system are generally assumed to have the potential to impair driving ability. In a retrospective survey, police files and the results of toxicological urine analysis from drivers suspected of driving under the influence of drugs in Vienna from 1993 to 1996 were investigated. Decisive for police intervention was "unsafe driving" (swerving, hesitating, going too slowly, etc.), driving at high speed within the city limits, driving through red lights or stop signs, and driving at night without lights. In one-fifth of the cases drivers caused a traffic accident. Casting suspicion on driving under influence of drugs was mainly caused by impaired coordination of movements, bloodshot eyes, slurred speech, drowsiness, conspicuous behavior, and changed pupils. In the majority of the study population more than two symptoms were recorded by police. In 94% of the cases police suspicions could be confirmed by toxicological urine analysis.

Adolescent↗
PubMed1997

Sudden, unexpected death of a young marathon runner as a result of bronchial malformation.

Deaths of young athletes are mainly caused by cardiac problems. Noncardiac deaths are infrequent and related to heat stress, drugs, sickle cell trait, and asthma. Herein, we report the case of a 28-year-old man, who collapsed during a marathon race, within sight of the finish line. Despite immediate resuscitation, he died shortly after hospitalization. Autopsy findings revealed neither unambiguous cardiac nor previously published noncardiac causes. Traumatic or drug-related death was excluded as well. We did find, however, focally hyperinflated pulmonary areas adjacent to atelectasis, interstitial emphysema, and mucosal infoldings of several bronchi. Histologically, two-thirds of medium-sized bronchi presented paucity of cartilages. Hence, the resulting flaccidity of the bronchial wall might cause bronchial obstruction, which we related to the genesis of this sudden and unexpected death.

Adult↗
PubMed1996

Pharmacokinetic studies of the fragrance compound 1,8-cineol in humans during inhalation.

The present study was undertaken to investigate the pharmacokinetics of 1,8-cineol in human subjects during prolonged inhalation. The results showed that 1,8-cineol is well absorbed from breathing air, with a peak plasma concentration after approximately 18 min. The elimination of this fragrance compound from the blood is biphasic, with a mean distribution half-life of 6.7 min and an elimination half-life of 104.6 min.

Administration, Inhalation↗
PubMed1996

Suicidal chloroquine poisoning: clinical course, autopsy findings, and chemical analysis.

Suicidal overdose of chloroquine is rare. We present a 14-year-old girl who was admitted to our Emergency Department after intentional ingestion of 7.5 g of chloroquine base followed by cardiac and respiratory arrest. Despite early mechanical ventilation, cardiac support, and treatment with high doses of diazepam, the patient died. Laboratory investigation indicated disseminated intravascular coagulation confirmed by petechial hemorrhages in the leptomeninges at autopsy, a finding that has not previously been described. Postmortem tissue analysis demonstrated early drug distribution to the medulla oblongata and cerebellum.

Adolescent↗
PubMedDate not supplied

Identification of the general unknown. Application of mass selective detectors in forensic toxicology.

One of the basic aims of forensic toxicology is the identification of previously unknown drugs and poisons. This is frequently achieved using the combination of gas chromatography and benchtop quadrupole or ion trap mass spectrometers. The influence of matrix loading on the mass spectral quality was tested, and it was found that a realistic amount of matrix changed the pattern of the spectra obtained by the ion trap mass spectrometer. Disturbed mass spectra led to unsuitable suggestions from the library search and thus rendered the identification of the "general unknown" more difficult. On the other hand, higher selectivity and lower detection limits favored the ion trap technology for target analysis because of the capability of MS-MS.

Adult↗