PubMed Health⌕ Search

Biomedical subjects

F Frei

Publications and source records attributed to F Frei.

At least 19 recordsLinked to original sources
PubMed1996

[Helicopter use in the Swiss air rescue service for children. Inland transport in 1992].

In 1992, the Swiss helicopter rescue service (REGA) transported 515 injured and 141 sick children (total n = 656). More than 60% of the children were boys; the age group from 10 to 16 years dominated. Primary care was provided in 415 of the flights, whereas the remaining cases were interhospital transfers to institutions with pediatric intensive care units. The main reason for primary interventions was sports accidents, followed by medical disease and traffic accidents. The majority of the sick children (70%) were severely ill with life-threatening diseases according to National Advisory Committee for Aeronautics (NACA) indices IV to VII. On the other hand, only 47% of the injured children had NACA indices of IV to VII. Most of these children had minor injuries suffered during sports activities; they were rescued mainly because of the site of the accident and not the severity of the injury. The remaining trauma victims had had traffic or home accidents and were usually severely injured. Head injuries were the most common reason for intervention due to accidents, and central nervous disorders and respiratory problems were the main reason for interventions in children suffering from serious illnesses. For primary REGA rescue interventions, the mean time from accident to arrival at the hospital was 64 minutes: 18 minutes from injury to alarm, 17 minutes from alarm to arrival at the scene, and 29 minutes for scene time and flight to the hospital. Costs for helicopter rescue are twice as high as for ground-based rescue (ambulance). However, considering the relatively high percentage of severely injured or life-threatened sick children involved, air rescue and its higher costs appear to be justified.

Adolescent↗
PubMed1996

[Local infiltration of epinephrine and bupivacaine before tonsillectomy].

The effects of peritonsillar injections of epinephrine and local anesthetics before tonsillectomy on blood loss and postoperative pain were evaluated in a prospective, randomized double-blind trial on 103 children. Patients were randomly assigned into one of three groups: controls given injections of 0.9% NaCl (n = 34), patients injected with 0.4 ml/kg (1:200,000) epinephrine combined with 0.25% bupivacaine (n = 33) and patients given only 1:200,000 epinephrine (n = 36). All injections and operations were performed by the same surgeon (KS). Blood loss was calculated by weighing all blood aspirated perioperatively and swabs used during surgery. Postoperative pain was assessed at regular intervals by using three methods: (1) use of a visual analogue scale by parents and nurses to estimate pain; (2) postoperative need for nalbuphine as analgesic; (3) the Hannallah-Broadman semi-objective pain score (including crying, anxiety, restlessness, and changes in blood pressure). The mean blood loss in the control group (given NaCl) was 132 g, which was significantly increased when compared with the epinephrine/bupivacaine group (85 g) and the group treated with only epinephrine (90 g). However, analysis of the postoperative pain scores did not reveal any significant differences among groups. These findings indicate that the peritonsillar injection of bupivacaine does not decrease postoperative pain, but peritonsillar injections of epinephrine will significantly reduce blood loss during tonsillectomy.

Adenoidectomy↗
PubMed1994

Ethopharmacological analysis of rat behavior on the elevated plus-maze.

Behavioral categories were measured in rats left on an elevated plus-maze for 5 min, in addition to the traditional measures. Four independent factors emerged from a factor analysis. The variables that loaded highly and positively on Factor 1, seemingly related with anxiety, were: number of entries onto open arms, time spent on open arms, percentage of open/total arm entries, percentage of time on open arms, scanning over the edge of an open arm, and open arm end-exploring. The time spent on enclosed arms loaded highly, but negatively on the same factor. Risk-assessment from an enclosed arm also loaded negatively on Factor 1. Number of enclosed arm entries, total number of arm entries and rearing loaded highly on Factor 2, probably related to motor activity. However, the total number of entries also loaded on Factor 1, being thus a mixed index. Similarly, the number of open arm entries loaded on both Factors 1 and 2. As expected, the variables having high loads on Factor 1 were changed to one direction by administration of two anxiolytics (nitrazepam and midazolam) and to the opposite direction by two anxiogenic drugs (pentylenetetrazol and FG 7142). Such pattern of drug effects was not observed with the remaining variables.

Animals↗
PubMed1994

[Effect of halothane anesthesia on cerebral blood flow velocity in children].

The effects of halothane on the cerebral circulation were studied in 23 children during general anaesthesia. Blood flow velocity in one middle cerebral artery was recorded continuously by transcranial Doppler sonography. Furthermore arterial blood pressure, pulse rate, endtidal CO2partial pressure and endtidal halothane concentration were recorded. Mean flow velocities/mean arterial blood pressures were 79 cm x s-1/65 mmHg; 86 cm x s-1/61 mmHg; 78 cm x s-1/54 mmHg and 67 cm x s-1/48 mmHg with 1; 1.5; 2 and 2.5 per cent endtidal halothane concentrations, respectively. Endtidal CO2-partial pressure and pulse rate remained constant throughout the study. The higher cerebral blood flow velocities seen with 1.5 per cent halothane compared with 1 per cent can be explained by an increase in cerebral blood flow. The lower cerebral blood flow velocities and arterial blood pressure with 2.5 per cent halothane compared with 1.5 per cent indicate impaired cerebral autoregulation. However, cerebral blood flow appeared to be sufficient even with low arterial blood pressures.

Anesthesia, General↗
PubMed1993

Effects of laryngoscopy and tracheal intubation on cerebral and systemic haemodynamics in children under different protocols of anaesthesia.

The effects of laryngoscopy and tracheal intubation on cerebral and systemic haemodynamics were studied in 30 children. The objective was to identify conditions in which the alterations of cerebral and systemic haemodynamics were minimal. The children were intubated after muscular relaxation and following 10 min of mechanical ventilation with end-tidal halothane concentrations of 1.5%, 2.0% and 2.5%, respectively. With 1.5%, 2.0% and 2.5% end-tidal halothane, the mean flow velocity increased by 26%, 19% and 5%, the mean blood pressure by 14%, 10% and 1%, and the heart rate by 26%, 8% and 5% respectively after intubation. Adverse effects of laryngoscopy and tracheal intubation on cerebral haemodynamics in children can be avoided by adequate anaesthetic protocols.

Anesthesia, Inhalation↗
PubMed1993

Central nervous system symptoms after intravenous lignocaine: dose-response during pregnancy.

There is continuing controversy over what dose of what drug should be used to identify an accidental intravascular or subarachnoid catheter placement in obstetric epidural anaesthesia. The purpose of this randomized, double-blind study was to evaluate the dose-effect relationship for the production of central nervous system (CNS) symptoms by intravenous lignocaine. Sixty first-trimester, pregnant patients divided into groups of 10 received saline or one of five doses of lignocaine (0.39, 0.5, 0.63, 0.79, and 1.0 mg kg-1) i.v. An ED95 of 1.12 mg kg-1 was calculated to produce reliable CNS symptoms when injected intravascularly. Lignocaine is an effective and reliable marker for intravenous injection in pregnant women.

Abortion, Therapeutic↗
PubMed1992

Influence of general anesthesia on transiently evoked otoacoustic emissions in humans.

The influence of general anesthesia (GA) on transiently evoked otoacoustic emissions (TEOAEs) was studied in 19 normally hearing women undergoing surgery. Emissions were measured on the day before the operation, after premedication but before the beginning of the operation, and during and after the operation. There were no significant differences in TEOAE amplitude or in reproducibility between results obtained the day before the operation and after premedication. Ten patients received nitrous oxide (N2O) during GA (N2O group), and 9 patients did not (non-N2O group). The amplitude of TEOAEs was reduced during GA in 9 of 10 patients in the N2O group and in 7 of 9 patients in the non-N2O group. However, the average decrease of amplitude after the first 10 minutes was greater in the N2O group (4 +/- 3.4 dB) than in the non-N2O group (0.18 +/- 1.4 dB). The corresponding mean reproducibility of the response decreased in 9 of 10 patients of the N2O group (29% +/- 24%) and was nearly unchanged in the non-N2O group (2.3% +/- 7.2%). The time course of the amplitude reduction was similar in both groups. The smallest amplitudes were reached on an average by 19.3 +/- 11.4 minutes in the N2O group and by 17 +/- 13.6 minutes in the non-N2O group. Preoperative and postoperative TEOAEs were comparable in level and reproducibility. Differential frequency effects imply a middle ear effect for the greater reduction of TEOAE amplitudes in the N2O group due to gas diffusion into the middle ear.(ABSTRACT TRUNCATED AT 250 WORDS)

Acoustics↗
PubMed1991

[Diagnosis of susceptibility for malignant hyperthermia using in-vitro muscle contraction testing in Switzerland].

Malignant hyperthermia is a potentially fatal pharmacogenetic disorder triggered by volatile anesthetics (halothane, enflurane, isoflurane) and/or succinylcholine. The inheritance of malignant hyperthermia susceptibility is thought to be autosomal dominant and the incidence could be as high as 1:10,000. The only generally accepted diagnostic method at present involves a muscle biopsy followed by in-vitro halothane and caffeine contracture tests. 100 individuals from 45 families who were considered to be potentially malignant hyperthermia-susceptible were investigated from 1986 to 1990 by in-vitro muscle contracture tests using the protocol of the European Malignant Hyperthermia Group. Of 45 families analyzed, 28 had at least one person who was susceptible to malignant hyperthermia with a total of 64 malignant hyperthermia-susceptible individuals. 36 subjects in the 45 families were normal. In addition, our study shows that a femoral nerve block can be used in outpatients as a reliable anesthetic technique to perform biopsies from the vastus medialis muscle for malignant hyperthermia screening.

Adolescent↗
PubMed1988

Anaesthetic uptake and elimination: is there a difference between halothane and isoflurane in the dog?

In two groups of dogs, the uptake and elimination of halothane and isoflurane were studied using a closed-loop anaesthetic system which automatically controlled end-tidal halothane and isoflurane partial pressures at equi-MAC concentrations. Haemodynamic and respiratory variables were recorded and the anaesthetic partial pressures were measured in the inspired and expired air, as well as in the arterial, cerebrovenous and mixed venous blood. The controller delivered a higher inspired partial pressure of halothane than of isoflurane to compensate for the higher blood/gas partition coefficient. The partial pressures of halothane in the arterial, cerebrovenous and mixed venous blood increased at rates similar to those of isoflurane. During 160 min of uptake, the cerebral venous partial pressures remained significantly lower than the arterial partial pressures for both agents. On discontinuation of the anaesthetic, the partial pressures of halothane and isoflurane decreased at equal rates in arterial, cerebrovenous and mixed venous blood, and in end-tidal gas. It was concluded that the rate of uptake of isoflurane is more rapid than that of halothane from the alveolar space to the blood, but not from the blood to brain tissue. The rates of elimination from brain tissue and from blood were found to be similar for both agents.

Anesthesia, Inhalation↗
PubMed1986

Control of end-tidal halothane concentration. Part B: Verification in dogs.

Conventional anaesthetic techniques do not allow for the automatic control of end-tidal halothane concentration and, therefore, brain concentration cannot be predicted. In this study, eight dogs were ventilated with halothane in oxygen using a new closed-loop anaesthetic breathing system which provided a constant end-tidal concentration. During the first 60 min the end-tidal concentration was maintained at 0.87 vol% (1 MAC). Then followed 60 min of halothane wash-out and a further 120-min period of halothane at 1.74 vol% (2 MAC). Halothane concentrations were measured in the inspired and expired air, and in the arterial, cerebral venous and mixed venous blood. Haemodynamic and respiratory variables were measured. The system reached 95% of the target end-tidal concentration within 6 min without over-shooting. After 2 h of wash-in, significant gradients still persisted between end-tidal, arterial and cerebral venous blood concentrations. Measured uptake differed from theoretically calculated uptake by 18.3-57.6%, depending on the model used. Measured arterial and cerebral venous concentrations differed from theoretically calculated values by 7% and 17.5%, respectively. It was shown that the required end-tidal concentrations can be obtained rapidly and accurately, and that brain tissue concentrations can be predicted within certain limits.

Anesthesia, Inhalation↗
PubMed1982

[Trichinellosis with neurological complications. Case report and short overview].

A 53-year-old, previously healthy man developed persistent diarrhea 4 days after ingestion of smoked but uncooked pork sausages in the Southern Tyrol. On his return to Switzerland he ate the same sausages and was admitted to hospital with migrating muscle pain, fever and chills. While fever and diarrhea soon regressed, the patient exhibited neurologic symptoms and change of character. The leukocyte count was 14 000/mm3 with 39% eosinophils. 40 days after hospitalization a second muscle biopsy established the diagnosis of Trichinella spiralis infection. At the same time, serologic tests were positive for Trichinella spiralis. Epidemiology, parasitology, symptomatology, diagnosis, therapy, prophylaxis and prognosis of trichinellosis are briefly discussed.

Adrenal Cortex Hormones↗
PubMedDate not supplied

Carrier screening for cystic fibrosis: costs and clinical outcomes.

OBJECTIVES: To evaluate the costs and clinical effects of 16 alternative strategies for cystic fibrosis (CF) carrier screening in the reproductive setting; and to test the sensitivity of the results to assumptions about cost and detection rate, stakeholder perspective, DNA test specificity, chance of nonpaternity, and couples' reproductive plans. METHOD: Cost-effectiveness analysis. RESULTS: A sequential screening strategy had the lowest cost per CF birth avoided. In this strategy, the first partner was screened with a standard test that identifies 85% of carriers. The second partner was screened with an expanded test if the first partner's screen was positive. This strategy identified 75% of anticipated CF births at a cost of $367,000 each. This figure does not include the lifetime medical costs of caring for a patient with CF, and it assumes that couples who identify a pregnancy at risk will choose to have prenatal diagnosis and termination of affected pregnancies. The cost per CF birth identified is approximately half this figure when couples plan two children. CONCLUSIONS: The cost-effectiveness of CF carrier screening depends greatly on couples' reproductive plans. CF carrier screening is most cost-effective when it is performed sequentially, when the information is used for more than one pregnancy, and when the intention of the couple is to identify and terminate affected pregnancies. These conclusions are important for policy considerations regarding population-based screening for CF, and may also have important implications for screening for less common diseases.

Cost-Benefit Analysis↗