PubMed Health⌕ Search

Biomedical subjects

D Holst

Publications and source records attributed to D Holst.

At least 37 records · Page 2Linked to original sources

No risk of metal toxicity in combined spinal-epidural anesthesia.

UNLABELLED: Using the single level needle-through-needle technique for combined spinal-epidural anesthesia (CSE) may introduce very fine metal particles abraded by the spinal needle from the inner ground edge of the Tuohy needle into the patient. Either the local anesthetic administered epidurally or the peridural catheter may also pass intrathecally through the hole in the dura made by the spinal needle. To examine these concerns, the needle-through-needle technique was simulated in an in vitro model (18-gauge Tuohy needle; 27- or 29-gauge Quincke needle). The presence of abraded metal particles was identified by atomic absorption spectrography (AAS). The needles were then examined under an electron microscope. Metal particles could not be identified by using AAS in the needle-through-needle technique after normal clinical use, nor could traces of use be revealed by using an electron microscope to examine the Tuohy needle. With intentionally rough handling and caudal orientation of the spinal needle tip, minimal scratches could be seen by using an electron microscope, but there were no metal particles detected by AAS. In an anatomical preparation, the possible passage of the epidural catheter anesthetic through the dural puncture hole into the cerebrospinal fluid compartment was investigated endoscopically. Neither passage of dyed epidural local anesthetic nor penetration of the epidural catheter into the cerebrospinal fluid compartment could be demonstrated by endoscopy. We conclude that the needle-through-needle-technique is an acceptable way of performing CSE anesthesia. Endangering the patient by an unintentionally intrathecal misplacement of the epidural catheter seems to be very unlikely based on our in vitro model if small spinal needles (27- or 29-gauge) are used. IMPLICATIONS: Atomic absorption spectrography shows no contamination of the intrathecal compartment by abraded metal particles from the Tuohy needle by combined spinal-epidural anesthesia with the needle-through-needle technique. In vitro, neither passage of dyed epidural local anesthetic nor penetration of the epidural catheter into the cerebrospinal fluid compartment could be demonstrated by endoscopy.

Anesthesia, Epidural↗

In vitro investigation of cerebrospinal fluid leakage after dural puncture with various spinal needles.

UNLABELLED: Postspinal headache is one of the most common complications of spinal anesthesia and has repeatedly led to controversy concerning needle size and configuration. In an in vitro investigation, we measured cerebrospinal fluid (CSF) leakage with Sprotte, Whitacre, Quincke, and Atraucan needles under physiological conditions in human dura. The puncture characteristics were examined under an electron microscope. The pencil-point needles show 2-3 times less leakage of CSF compared with the cutting Quincke needles of corresponding size. Between the Sprotte and the Whitacre needles, there were no significant differences. The least loss of CSF occurred with the 26-gauge Atraucan needle. Under the electron microscope, a sharply delineated, persistent perforation channel was shown with the Quincke needles, which may explain the high CSF loss. With pencil-point needles, which push the tissue apart bluntly, a large opening on the inside is found, with some tearing of the dura. However, in contrast to the cutting needles, a persistent perforation channel is not manifested. The 26-gauge Atraucan needle, which both cuts and pushes apart conically, shows a relatively discrete opening on the inside, with slight tears in the dura and arachnoidea but without a visible perforation channel. The results of our study show that larger needles (26-gauge Atraucan) that are easier to handle can lead to good and, in some cases even better, puncture results if they have characteristics of both the cutting and the pencil-point needles. IMPLICATIONS: We compared several brands of pencil-point and standard cutting spinal needles of varying sizes. All pencil-point needles had less cerebrospinal fluid leakage, the least loss occurring with 26-gauge Atraucan needles. Electron microscopic examination of the dura after puncture showed characteristic findings with each needle type. We conclude that the combined cutting and pencil-point characteristics seen in the Atraucan needle may have clinical advantages.

Cerebrospinal Fluid↗

Changes in the oral health of adults from Trøndelag, Norway, 1973-1983-1994.

The purpose of this paper is to describe the changes in the oral health of adults from Trøndelag, Norway, over two decades (1973-1983-1994), from both a quasi-longitudinal and a time-lag perspective. Study participants were selected by random sampling in 1973, 1983 and 1994 (n=1759, n=3195, n=2341). Data were collected by epidemiological registrations and questionnaires. Oral health was measured by the additive DMF index. The number of decayed teeth was low in all age groups in 1994. There was a reduction in the number of filled teeth from 1983 to 1994 in the time-lag perspective in the youngest age group and the urban middle-aged group. The rural middle-aged adults and the older adults showed more filled teeth in 1994 than in 1983. In a quasi-longitudinal perspective, no significant changes in the 1960 birth cohort and the 1939-48 urban birth cohort were shown from 1983 to 1994, while the 1930-38 birth cohort and 1939-48 rural birth cohort acquired more filled surfaces during this period. There are now at least two different oral health populations of adults. The younger with the potential to carry oral health benefits into old age, and an elderly population burdened with extensive treatment but keeping their natural teeth.

Adolescent↗

Increasing number of teeth present in a quasi-longitudinal study in adults: a methodological note.

This paper discusses the impossible result of an increase in the number of teeth present in a quasi-longitudinal study of an adult population. In 1983 and 1994, random samples were drawn from birth cohorts 1939-48 and 1930-38. The paradoxical result that adults acquired new teeth in the quasi-longitudinal study gave rise to questions about the comparability of the two samples. Four main sources of failure in comparability are described and discussed: instrumental stability, criteria consistency, response bias, and compositional change in aging cohorts. The lower response rate among persons with two edentulous jaws, and possibly among persons with one dentate jaw, was concluded to be the main reason for the increase in the overall group median and mean number of teeth present. In general, in studies with a similar study design, problems of comparability between the samples demand one's attention and should therefore be carefully evaluated. Compositional change of the population as a source of failure in sample comparability cannot be avoided, while the other three sources (instrumental stability, criteria consistency, response bias) can largely be avoided by careful planning and efficient use of resources.

Adult↗

Pattern of attendance to dentists and hygienists in the County of Göteborgs and Bohus län during 1990-1992.

AIM: To describe the dental care consumption in a random sample of the population of a Swedish county 1990-1992 and to compare this with results from other Swedish studies, especially those using different self-reporting methods. SUBJECTS: One sixtieth of all adult inhabitants in the County of Göteborgs and Bohus län (all individuals born on the 17th day of an odd month) formed the sample. DESIGN: All insurance claims sent from both public and private dentists to the local insurance offices were registered in a data base. Thus every treatment registration was collected into this data base, independently, whether it was made in a private clinic or in the Public Dental Service and whether or not by a dental hygienist or other grade. Since almost all dental care in Sweden was performed within the dental insurance system, these registrations could be regarded as very near to the total dental care consumption of this group. The registrations were related to the age of the patient, the type of care (acute/regular), regularity, dental hygienist treatment and other factors. RESULTS: It was found that the youngest and the oldest patients visited a dentist less often, that approximately a quarter received hygienist care, that many received emergency treatment sometime during the observation period but that a majority also had regular dental care. Studies using a self-reporting technique reported a systematically higher level of consumption than those using insurance claim registration. CONCLUSIONS: Dental care consumption studies using self-reporting methods will probably overestimate the actual consumption. Emergency treatment is frequent even among patients who go to a dentist regularly.

Adult↗

Effect of capsaicin on airway responsiveness to hypertonic saline challenge in asthmatic and non-asthmatic children.

Recurrent cough and asthma are common problems in children. In the evaluation of children with recurrent cough, the sequential measurements of airway responsiveness (AR) and capsaicin cough receptor sensitivity may be useful. However, the effect of capsaicin on AR induced by an indirect stimulus such as hypertonic saline (HS) is not known. Current evidence suggests that a common pathway is involved in both capsaicin and HS challenges. This study was designed to determine whether inhalation of capsaicin for the cough receptor sensitivity test before HS challenge will alter AR of asthmatic and non-asthmatic children to that challenge. Twenty-one children (12 asthmatics, 9 non-asthmatics; mean age, 11.3 years) performed the HS challenge alone or 2 min after capsaicin inhalation on 2 different days in random order. The end point of the capsaicin inhalation was when > or = 5 coughs were stimulated from a single inhalation. The power of the study was > 90% at a significance level of 0.05. Capsaicin inhalation prior to HS challenge did not alter the AR of normal children. In the asthmatic group, the PD15 (provocation dose causing a fall in forced expiratory volume in 1 s of > or = 15% from the baseline) without prior inhalation of capsaicin (mean, 2.44 +/- SEM 1.21 ml) was not significantly different from that when HS challenge was performed after capsaicin inhalation (mean, 2.19 +/- SEM 0.83 ml). The mean of the difference in log PD15 of the HS challenge with and without capsaicin was -0.02 (95% CI, -0.16, 0.12), i.e. within the equivalence range of the HS challenge in children with asthma. We conclude that in normal and asthmatic children, capsaicin inhalation does not alter AR to HS; consequently the capsaicin cough sensitivity test can be performed validly before an HS challenge.

Adolescent↗

[Circulatory reactions under spinal anesthesia. The catheter technique versus the single dose procedure].

UNLABELLED: Life-threatening cardiovascular complications are a serious risk even for healthy patients during spinal/epidural anaesthesia. The incidence of fatal cardiovascular complications for epidural anaesthesia is 1:10000, for spinal anaesthesia 1:7000. In contrast, general anaesthesia has an overall mortality of only 1:28000. Administration of IV fluids to minimise the haemodynaemic reactions of beginning sympatholysis is not always sufficient. In this study, we examined whether fractionated application of local anaesthetics via a spinal catheter would provide better haemodynamic stability. METHODS: In a prospective study, we examined the haemodynaemic reactions of 300 patients during single-dose (n = 150) versus continuous spinal anaesthesia (CSA) (n = 150). Isobaric bupivacaine 0.5% was given through a 29 G Quincke needle (3.5 ml) or a 28 G spinal catheter (1.5 ml as a bolus, followed by 1 ml/10 min until an anaesthetic level of T12 was reached). RESULTS: The sensory and motor effects of both methods were comparable. The T12 level of anaesthesia was achieved with the single-dose method after 10.5 min and with the continuous method after 19.1 min. After single-dose anaesthesia, the blood pressure dropped by 16.5% and the heart rate by 12% compared to the control values. During CSA no significant blood pressure changes were recorded; the heart rate decreased by 8%. In 15 cases vasoconstrictors had to be given to stabilise the lowered blood pressure after single-dose anaesthesia. CONCLUSION: With the use of CSA, the haemodynamic effects of sympatholysis can be minimised. This method thus has advantages, especially for high-risk cardiovascular patients.

Adult↗

Cardiopulmonary effects of enoximone or dobutamine and nitroglycerin on mitral valve regurgitation and pulmonary venous hypertension.

OBJECTIVE: To compare the cardiovascular and pulmonary effects of the phosphodiesterase III inhibitor enoximone (EN) or a combination of dobutamine (DOB) and nitroglycerin (NTG) before and after mitral valve repair or replacement. DESIGN: Prospective, randomized, controlled clinical study. SETTING: University hospital. PARTICIPANTS: Twenty patients with mitral regurgitation and pulmonary venous hypertension scheduled for elective mitral valve surgery. INTERVENTIONS: Patients fulfilling the inclusion criteria of the study were randomly allocated into a group treated with EN (group 1, n = 10) or DOB and NTG (group 2, n = 10). A cardiopulmonary status was obtained after induction of anesthesia and mechanical ventilation during stable hemodynamic conditions (control). Then the patients received either EN (bolus dose 1.0 mg/kg followed by a continuous infusion of 10 micrograms/kg/min) or DOB (8.0 micrograms/kg/min) and NTG (1.0 microgram/kg/min) according to the randomization. After a period of 20 minutes, all parameters were measured again. The study drugs were stopped, and cardiac surgery was performed. Infusions of EN (without additional loading dose) or DOB and NTG were started again in the above-described doses 10 minutes before separation from cardiopulmonary bypass (CPB). Respiratory and hemodynamic measurements were made 20 minutes after weaning from CPB and 60 minutes after admission of the patient to the intensive care unit. MEASUREMENTS AND MAIN RESULTS: Both groups were comparable regarding preoperative and control data. Before mitral valve surgery, cardiac output (CO) and heart rate (HR) increased by 46% (p < 0.05) and 31% (p < 0.01) during infusion of EN with minor changes of mean systemic arterial pressure (PSA) and gas exchange. Mean pulmonary arterial pressure (PPA) decreased from 32 +/- 11 mmHg to 23 +/- 11 mmHg (p < 0.05). Similar alterations were observed in group 2 (delta CO + 26%, p < 0.05, delta HR + 39%, p < 0.01); however, PPA and calculated pulmonary vascular resistance remained unchanged. After separation from CPB, EN and DOB-NTG achieved comparable effects on CO, HR, and PSA, but PPA was significantly lower in group 1. In addition, venous admixture and alveolo-arterial oxygen tension gradient were lower in EN-treated patients. CONCLUSION: Enoximone or DOB and NTG have comparable effects on CO, PSA, and HR in mitral regurgitation and pulmonary hypertension, but EN is more effective in reducing PPA without deterioration of gas exchange.

Adrenergic beta-Agonists↗

Effect of thoracic epidural anaesthesia on ventilation-perfusion distribution and intrathoracic blood volume before and after induction of general anaesthesia.

BACKGROUND: Gas exchange is impaired during general anaesthesia due to development of shunt and ventilation-perfusion mismatching. Thoracic epidural anaesthesia (TEA) may affect the mechanics of the respiratory system, intrathoracic blood volume and possibly ventilation-perfusion (VA/Q) distribution during general anaesthesia. METHODS: VA/Q relationships were analyzed in 24 patients undergoing major abdominal surgery. Intrapulmonary shunt (Qs/QT), perfusion of "low" VA/Q areas, ventilation of "high" VA/Q regions, dead space ventilation and mean distribution of ventilation and perfusion were calculated from the retention/excretion data of six inert gases. Intrathoracic blood volume (ITBV) and pulmonary blood volume (PBV) were determined with a double indicator technique. Recordings were made before and after administration of 8.5 +/- 1.5 ml bupivacaine 0.5% (n = 12) or 8.3 +/- 1.8 ml placebo (n = 12) into a thoracic epidural catheter and after induction of general anaesthesia. RESULTS: Before TEA, Qs/QT was normal in the bupivacaine group (2 +/- 2%) and the placebo group (2 +/- 3%). TEA covering the dermatomal segments T 12 to T 4 had no effect on VA/Q relationships, ITBV and PBV. After induction of general anaesthesia Qs/QT increased to 8 +/- 4% (bupivacaine group, P < 0.05 and to 7 +/- 2% (placebo group, P < 0.05). ITBV and PBV decreased significantly to the same extent in the bupivacaine group and the placebo group. CONCLUSIONS: TEA has no effect on VA/Q distribution, gas exchange and intrathoracic blood volume in the awake state and does not influence development of Qs/QT and VA/Q inequality after induction of general anaesthesia.

Anesthesia, Epidural↗

Future treatment needs in children, adults and the elderly.

Future treatment needs for dental services are discussed in the perspective of the objective which the services are meant to fulfill. These are, broadly speaking, equal distribution of services and economic efficiency. Within the Nordic countries, the emphasis has been on equity, perhaps less on efficiency. Equity of utilization is best understood as being a situation where patients with equal needs for oral health care receive equal treatment, in terms of both the volume and the quality of the services. The justification for arguing that equality of utilization is the appropriate measure is mainly based on the externality argument: health-care consumption by one person may be the source of utility to another person. According to that view there are two beneficiaries of dental care: the patient who is sick, and the rest of society who care for the sick patient and who derive utility from seeing the patient become healthy. The public dental services for children in the Nordic countries are organized according to the principle of equity of utilization. Equity of access is best understood as being a situation where people with equal needs have equal opportunity to use dental services. It is a supply-side phenomenon; equal access is achieved when patients with the same needs face the same costs of dental-care consumption in terms of both time and money. The oral health situation among children, adults and the elderly is exemplified by national service data and recent studies.

Adolescent↗

Social relations and their health impact in tree shrews.

In the wild, tree shrews (Tupaia belangeri) live in pairs in territories which they defend vigorously against strange conspecifics. The paper gives an overview on some of our laboratory studies with tree shrews, which demonstrate the great relevance the concepts of Jim Henry have in understanding the biological relevance of mammalian social behavior. A basic result of these studies is that the physiological consequences of social relations between mammals depend on the appraisal of the situation by the animals and their coping behavior. Appraisal of a stimulus or a situation, as well as the resulting coping behavior, are basically psychological processes. There are, therefore, no simple relationships between stimuli imposed on individuals and their physiological responses; rather the behavioral, psychological and, thus, the physiological responses of individuals to stimuli differ depending on their genetics, prenatal influences and postnatal learning processes. This means, to understand the consequences of social relations between individuals, an integrated approach is required to assess which factors, including social rank and bonds to conspecifics, interact to affect an individual's fertility and health, as has been so clearly demonstrated in the work of Jim Henry.

Animals↗

Testing the consistency of measurements of the distance between the cemento-enamel junction and the alveolar bone crest on bitewing radiographs.

UNLABELLED: The purpose of the research described in this paper is to test the consistency of measurements of the distance between the cemento-enamel junction and the alveolar bone crest (CJ-AC) on bitewing radiographs. The present paper shows how the consistency tests were organized and which statistical analyses were used. Since the actual characteristic (CJ-AC) could not alter, the variations of the results had to be due to one more of the 5 m-factors (man, material, machine, method and manipulation). To test the consistency of the measurements of CJ-AC, a pretest and an en route test were performed. Both the bitewing radiographs for the pretest and the en route test were sampled at random from the principal material. The principal material consisted of 856 sets of bitewing radiographs from persons born 1930-1949. The pretest of 40 sets of bitewing radiographs were read twice by 2 independent readers. The en route test consisted of 85 sets of bitewing radiographs which were read twice by 1 reader. Neither the results of the pretest nor the results of the en route test showed statistical or clinical differences of significance. IN CONCLUSION: the consistency of this method of measuring is satisfactory for the 2 readers.

Aged↗

[Spinal para-medullary conduction anesthesia in therapy with anticoagulant drugs].

Epidural and spinal blocks can lead to iatrogenic bleeding in the spinal canal. Incidence of this severe complication is considered low, but the risk of irreversible neurological defects for the patient requires increased attention by the anaesthetist. The perioperative risk is higher in patients under anticoagulant therapy. The different pharmacodynamics and pharmacokinetics of practically relevant anticoagulants are discussed and recommendations for the performance of centroneuraxis blocks in patients under anticoagulant therapy are given.

Anesthesia, Epidural↗

Individualizing recall intervals in child dental care.

Individualizing and extending recall intervals for children have been recommended in Norway to target resources efficiently. Recall intervals were changed for children aged 3-18 years in Drammen from 1991. Clinical time spent by dentists and dental hygienists, dental health status and length of recall intervals were registered from 1990 to 1993. For the child population, the mean recall interval changed from 12.5 to 13.7 months and the annual time spent per child was reduced by 14% from 1990-91 to 1992-93. Adjusted for the decline in number of new decayed teeth, the reduction in time spent was 11%. Children with intervals of 17 to 20 months had fewer new decayed teeth and their care required less personnel time than other children. For children with new decayed teeth, time spent for dental care was not associated with recall interval, while for children without new decayed teeth, longer recall intervals were associated with shorter time for dental care. The variation in number of decayed teeth and time spent for dental care was substantial at all intervals. Individualizing and extending recall intervals to some extent targeted resources at children with more dental disease. However, in the short run, inequality in dental health persisted. Limited extension of recall intervals did not interrupt the long-term trend toward better dental health in the children and substantial resources were saved in the dental services.

Adolescent↗

Hypertonic saline challenge in an epidemiologic survey of asthma in children.

To evaluate sensitivity and specificity of a 4.5% hypertonic saline challenge for a diagnosis of asthma, we studied 393 schoolchildren (13 to 15 yr of age) with "current wheeze," "former wheeze," and without history of wheeze in a community-based, cross-sectional survey. These children were selected from 2.836 schoolchildren in 26 schools in greater Melbourne, Australia who completed a self-administered questionnaire on respiratory symptoms, allergic rhinitis, and eczema. Three hundred eighty-two of 393 children successfully completed a 4.5% hypertonic saline challenge with increasing inhalation periods, and 365 of 393 performed a 6-min standardized, free running exercise challenge. The prevalence of bronchial hyperresponsiveness to hypertonic saline was 20.4%. Sensitivity and specificity for the hypertonic saline challenge to identify children with "current wheeze" were 47% and 92% respectively and for the exercise challenge, 46% and 88%. The agreement of response to hypertonic saline and to exercise was only moderate (kappa = 0.43). Factors associated with increased response to hypertonic saline in a multivariate logistic regression model were a history of "current wheeze," hay fever, response to the exercise challenge, female sex, and a lower baseline predicted FEV1. These results suggest that a 4.5% hypertonic saline challenge shows sensitivity and specificity similar to a standardized exercise challenge and pharmacologic challenges and a higher sensitivity than cold air hyperventilation and distilled water to identify asthma in children in a field study. Measurement of responsiveness to hypertonic saline may be of value as an objective marker of asthma to compare prevalence studies of bronchial hyperresponsiveness and of asthma over time and between countries.

Adolescent↗

Accessibility of dental services according to family income in a non-insured population.

The aim of this study was to examine the effect of family income on accessibility to dental services among adults in Norway. The analysis was performed on a set of national data collected in 1989, which was representative of the non-institutionalized Norwegian population aged 20 years and above. The sample size was 1200 individuals. The data were analyzed according to a two-part model. The first part determined the probability of whether the consumer had demanded the services or not during the last year according to family income. The second part estimated how the amount of services utilized depended on family income, for those with demand. The elasticity of the odds of having demanded the services with respect to family income was 0.48. Family income had no effect on the amount of services utilized. Additional analyses also showed that there was no effect of family income on the probability of having received a filling or a crown when visiting the dentist. In Norway, almost all costs for dental services are paid by the consumer. It is not possible from the data alone to say whether subsidized dental care is an effective way of reducing the inequalities in demand.

Adult↗