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Biomedical subjects

L Wallin

Publications and source records attributed to L Wallin.

At least 55 records · Page 3Linked to original sources
PubMed1989

Fluorescein angiography and distal arterial pressure in patients with arterial disease of the legs.

Fluorescein angiography (FA) of the foot soles was performed in 119 patients with arterial disease of the legs. Fluorescein was injected rapidly intravenously and sequential photographs were taken of the foot soles. Densitometric measurements were performed on three areas of each foot image: the big toe, the foot pad (just proximal to the little toe) and the heel. The relationships between different FA measurements and systolic arterial pressure in the ankle or the big toe were analysed. The appearance times of fluorescence correlated inversely with ankle pressure (P less than 0.001). The initial slopes of the fluorescence-time curves at all three sites of measurement correlated with ankle pressure (P less than 0.001). The initial slopes of fluorescence-time curves of the big toe and the foot pad correlated with toe pressure (P less than 0.001). In 12 patients effective arterial pressure was lowered by elevation of the feet, and in eight patients external pressure was applied to the foot by enclosing it in a box. The changes in FA evoked by these manoeuvres further strengthened the relationship between arterial pressures and FA measurements. We conclude that FA is a good method for evaluating circulation in the foot when neither ankle nor toe pressure is obtainable. In addition, FA may be useful when vascular disease is suspected in the presence of normal pressures, because the fluorescence distribution pattern was clearly abnormal in 11 of 16 such feet.

Adult↗
PubMed1989

Fluorescein angiography for predicting healing of foot ulcers.

Fluorescein angiography (FA) was performed on 83 patients (68 diabetics) with foot ulcer or gangrene. Densitometric measurements were made on the FA images, and different FA parameters were defined. These parameters, as well as systolic ankle and toe blood pressures, were evaluated for predicting the future course, i.e., whether healing would occur or whether major amputation below or above the knee had to be performed. The toe slope (i.e., the rate of increase of fluorescence on the big toe during the first 10 seconds after its appearance on the toe) predicted healing correctly in 0.83 and major amputation in 0.88. The ankle and toe pressures had only slightly lower predictive value. The combination of ankle pressure and toe slope predicted healing correctly in 0.91 and major amputation in 0.88. When ankle pressure cannot be measured, FA is the method of choice. Further, FA provides information on regional blood flow unobtainable by any other method.

Adult↗
PubMed1988

Therapeutic consequences of oesophageal function studies in patients with benign oesophageal disease.

Evaluation of oesophageal function was performed in 91 patients referred to a specialized department of cardiothoracic surgery for surgical treatment of benign oesophageal disease. Standard manometry was used in addition to radiology and endoscopy, and in some patients, an acid perfusion test, an acid clearing test, and a prolonged monitoring of pH in the distal oesophagus were additionally performed. The aim of this study was to evaluate whether assessment of oesophageal function is needed in such a patient group, and whether the results of these investigations were taken into account when making the final decision for therapy. Eleven percent of the patients referred with a diagnosis of hiatal hernia or reflux had achalasia or oesophageal spasm. Nine percent of the patients referred for motility disorders had reflux-related disease. The referral diagnosis was changed to a diagnosis with a different therapeutic approach in 16% of the patients. In 33%, a diagnosis of disordered oesophageal function was considered either at referral or during the routine assessment for oesophageal disease. Eighty-one percent of the patients with achalasia were treated in accordance with the manometric results. In all cases where an anatomical diagnosis was replaced by a diagnosis of disordered function, the treatment was in accordance with the findings of the motility studies. None of the patients with oesophageal spasm were suspected of having this disease. It is concluded, that not only anatomical features, but also functional considerations have to be taken into account when selecting treatment for benign oesophageal disease. Treatment failure and unnecessary surgical intervention can thus be avoided.

Adolescent↗
PubMed1988

Physical working capacity determined by different types of bicycle exercise tests.

Forty-three pairs and 10 triplets of bicycle exercise tests were performed. Seven different workload incremental procedures were used. Triplets and nine pairs of tests were performed by healthy subjects (n = 19) and 34 pairs of tests by patients (n = 19) 3 and 15 months after coronary by-pass operation. From each test result a hypothetical maximal workload sustainable for 6 min (Wmax6') was calculated. The two and three Wmax6' values obtained for each pair and each triplet of tests, respectively, were compared. The ratios between the corresponding Wmax6' values were 1.00 +/- 0.01 (mean +/- SE) for healthy subjects and 0.96 +/- 0.03 for patients. It is concluded that working capacities determined by bicycle exercise tests with different workload incremental procedures can be compared via the Wmax6'.

Adult↗
PubMed1988

Is standardization of pressure and pH measurement in the oesophagus possible to accomplish in the future?

The interpretation of the manometric results depends on reliable equipment and the technique used. The use of the Bernstein test and the acid clearing test are discussed. The difficulties in obtaining comparable results from long-term pH-measurement with different pH-probes, the placement of the probe and the problems with the position of the subject and the oral intake before or/and during the investigation are dealt with. It is concluded that standardization of the oesophageal function test within different centers are still a major problem, which will take considerable time to solve.

Esophagus↗
PubMed1988

The influence of age on esophageal acid defense mechanisms and spontaneous acid gastroesophageal reflux.

Association of age with gastroesophageal pH and motor parameters have been searched for previously, but most studies have been cross-sectional. The aim of the present investigation was to evaluate the influence of age on gastroesophageal sphincter pressure, acid clearing ability, and acid gastroesophageal reflux in the same group of normal subjects. Ten healthy subjects were investigated in the period May 4, 1977, to February 18, 1978, and reinvestigated in the period August 19, 1985, to January 29, 1986. The median interval between the two investigations was 8.0 yr, range 7.7-8.5 yr. There were eight men and two women, with a median age at the second investigation of 36 yr, range 30-53 yr. Measurement of gastroesophageal sphincter pressure (GESP) and an acid perfusion test were performed, and within the same week, an acid-clearing test and a prolonged monitoring of pH in the distal part of the esophagus were carried out (5 cm proximally to the GES). pH monitoring was initiated between 7 and 8 PM and terminated between 7 and 8 AM. There were no changes in GESP between the two investigations. All had a normal acid perfusion test in both investigations. No changes in acid-clearing ability could be demonstrated. Similarly, the number of reflux episodes, as well as the duration of acid reflux, were unchanged. Integration of the pH curve for pH values less than or equal to 4 gave similar results at both occasions. In addition, the relative time with pH values less than or equal to 4 was unchanged. The acidity of the potential reflux material did not change over time, as evaluated by intragastric pH before and after monitoring. In conclusion, this study did not demonstrate any influence of age on esophageal acid defense mechanisms or spontaneous gastroesophageal reflux.

Adult↗
PubMed1987

Relationship between spontaneous non-propagating pressure activity in the oesophagus and acid gastro-oesophageal reflux in pathological and non-pathological refluxers.

To evaluate the oesophageal motor activity preceding episodes of reflux, 10 pathological and 10 non-pathological refluxers and 26 normal subjects were investigated. The pressure events in spontaneous short periods of pressure activity (less than or equal to 60 sec) and in long activity periods were registered. The last contraction before reflux was more frequently found non-propagating than the last contraction of pressure periods not followed by reflux (p less than 0.01). The interval from the last contraction to reflux was shortest, if the contraction terminated in, or confined to the upper part of the oesophagus (p less than 0.001). Increased proportion of reflux episodes were preceded by an upper segmentary contraction (p less than 0.05) and a short activity period (p less than 0.02) in patients with pathological reflux in comparison with non-pathological refluxers. Spontaneously occurring sphincter relaxations might be triggered by preceding non-propagated contractile activity. The relative number of reflux episodes preceded by non-propagated pressure activity seems to be increased in patients with frequent episodes of acid reflux, compared with patients with infrequent episodes, or with normal subjects.

Adult↗
PubMed1987

Effect of cisapride on the gastro-oesophageal function in normal human subjects.

The aim of this study was to investigate oesophageal peristalsis and gastro-oesophageal function in normal subjects after 4 days of cisapride 10 mg p.o. 3 times/day and 10 mg 1.5 h before the investigation. The study was carried out in a double-blind cross-over design with coded cisapride or placebo tablets. Basal sphincter pressure increased after cisapride (p less than 0.002). The peristaltic pressure amplitude in the oesophageal body as well as the duration and velocity of the peristaltic pressure wave were measured after wet swallows. No changes were found. Intragastric pH was unchanged after cisapride. No effect was found on the result of a standard acid clearing test. Plasma concentration of cisapride did not correlate with any of the other variables. Oral cisapride increases fasting gastro-oesophageal sphincter pressure, but does not influence oesophageal peristalsis, acid clearing or intragastric pH in normal subjects.

Adult↗
PubMed1987

Acid gastro-oesophageal reflux and oesophageal pressure activity during postprandial and nocturnal periods. A study in subjects with and without pathologic acid gastro-oesophageal reflux.

The aim of the investigation was to evaluate the relative quantity of acid gastrooesophageal reflux during different time periods in subjects with and without pathologic reflux. Twenty duodenal ulcer patients, 10 with and 10 without pathologic acid gastro-oesophageal reflux, and 26 asymptomatic volunteers were subjected to 12 h of simultaneous monitoring of pH and pressure activity in the oesophagus. The monitoring period was divided into a 3-h postprandial period, a night period of 6 h, and a 3-h period in the morning. The highest reflux frequency and the longest duration of oesophageal acid exposure were found in the postprandial hours (p less than 0.001). Thereafter, all groups had an even reduction in reflux rate. A greater absolute reduction in the duration of oesophageal acid exposure could be measured in patients with pathologic reflux as compared with the other groups (p less than 0.001). In spite of this, both reflux frequency and time with acid in the oesophagus were increased during the night in patients with pathologic reflux (p less than 0.001). Pathologic refluxers had in total 11 times as much reflux as normal subjects, and in addition 37.9% of the reflux took place during the 6 night hours. In contrast, only 5.4% of the reflux recorded in normal subjects occurred during this period. The pressure activity during periods with a normal intraoesophageal pH was reduced in all three groups during the night (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Acid gastro-oesophageal reflux episodes as related to the quality of preceding peristalsis. A study in normal subjects.

It has earlier been demonstrated after long-term monitoring of pH and peristalsis in the oesophagus that episodes of acid gastro-oesophageal reflux occur in normal volunteers. To determine whether there is a connection between gastro-oesophageal reflux and prior peristalsis, pH and peristalsis were monitored for 12 h in 26 asymptomatic subjects. The recorded peristalsis was divided into brief bursts of peristaltic contractions (less than or equal to 60 sec) and more prolonged continuous activity. Peristaltic periods were limited to prior and subsequent peristalsis by a non-peristaltic course of greater than 30 sec. Continuous peristalsis was defined as a sequence of peristaltic contractions with a mutual distance between individual peristaltic waves of greater than or equal to 30 sec. A total of 81 episodes of reflux were recorded, of which 67 were preceded by peristaltic activity. Brief bursts of peristalsis, unrelated to reflux episodes, were frequently terminated by bolus-transporting peristaltic waves (p less than 0.001). When the last contraction before reflux was considered, an increased frequency of non-propagating peristalsis was found (p less than 0.01). In addition, a closer time relationship was observed between peristalsis and reflux if the last contraction was of the upper segmentary type, as compared with propagating activity (p less than 0.001). In conclusion, reflectory sphincter relaxation producing reflux may possibly be triggered by contractions in the upper part of the oseophagus, not followed by a bolus-transporting peristaltic wave.

Adult↗
PubMed1985

Effect of domperidone on gastro-oesophageal function in normal human subjects.

The aim of the study was to investigate gastro-oesophageal function in normal volunteers after oral administration of domperidone as a single dose (20 mg). The study was designed as a double-blind cross-over investigation. Ten healthy men (aged 27-50 years; median, 30) joined the study. Oesophageal function tests were performed, starting 1.5 h after intake of domperidone or placebo. Gastro-oesophageal sphincter pressure was measured with a perfused catheter system and a continuous pull-through technique. No changes in sphincter pressure were found. Peristaltic pressure amplitude in the body of the oesophagus and the duration and velocity of peristalsis were measured after wet swallows (bolus 5 ml of water). No changes were found. Intragastric pH did not change significantly after domperidone. No effect of domperidone on the results of a standard acid-clearing test could be found. Plasma concentrations of domperidone did not correlate with any of the other variables. In conclusion, domperidone given orally in a dose that has been shown to accelerate gastric emptying does not influence gastro-oesophageal sphincter pressure or peristaltic activity in the normal oesophagus.

Adult↗
PubMed1984

Antipsychotic treatment with alpha-methyltyrosine in combination with thioridazine: prolactin response and interaction with dopaminergic precursor pools.

The antipsychotic effect of alpha-methyltyrosine (alpha-MT) in combination with thioridazine was investigated by means of rating scales for "social behaviour" and "mental symptoms". The clinical effect was also evaluated in relation to the serum concentrations of alpha-MT and thioridazine and to the increase in prolactin secretion in response to the interaction with hypothalamic dopaminergic mechanisms. The interactions between the serum levels of alpha-MT and those of the transmitter precursors phenylalanine and tyrosine were analysed. The results confirmed the ability of alpha-MT (2 g/day) to potentiate the antipsychotic effect of thioridazine, whereby the dose of neuroleptic drug required to control psychotic symptoms may be markedly reduced. None of the four patients who completed the trial showed side effects that could be ascribed to alpha-MT. The antipsychotic effect of thioridazine, alone or in combination with alpha-MT, correlated well with the prolactin response in the individual patient. No important interference with serum phenylalanine or tyrosine levels was noted during treatment with alpha-MT.

Aged↗
PubMed1983

Gastro-oesophageal function in normal subjects after oral administration of ranitidine.

The aim of the study was to investigate gastro-oesophageal function in normal subjects after oral administration of 150 mg ranitidine as a single dose. The study was designed as a double blind crossover investigation. Ten healthy men, aged 26-49 years (median 29 years) joined the study. A series of oesophageal function tests were performed, starting 90 minutes after oral intake of ranitidine or placebo. Gastro-oesophageal sphincter pressure was measured using a perfused catheter system and a continuous pull-through technique. No changes in sphincter pressure could be demonstrated. Peristaltic amplitude in the body of the oesophagus as well as the duration and velocity of the peristalsis were measured after wet swallows (bolus 5 ml of water). We found no changes in these variables. Intragastric pH was measured and was higher after ranitidine than after placebo (p less than 0.005). Plasma ranitidine concentration did not correlate with intragastric pH. No effect of ranitidine could be demonstrated on the results of a standard acid clearing test. It is concluded that ranitidine, given orally in sufficient doses to suppress gastric acid secretion, does not influence gastro-oesophageal sphincter pressure or peristaltic activity in the oesophagus of normal subjects.

Adult↗
PubMed1983

Oesophageal peristalsis in normal subjects. Influence of pH and volume during imitated gastro-oesophageal reflux.

Acid gastro-oesphageal reflux in normal human subjects is followed by oesphageal peristalsis. The aim of the present study was to investigate the influence of pH and volume during imitated reflux on oesophageal peristalsis. Fluid volumes of 2.5, 5, 10, and 15 ml (pH 1.0, 4.0, or 7.0) were instilled randomly in the lower end of the oesophagus in eight healthy subjects. Further, repeated instillations were carried out in one subject. Oesophageal pressures were measured 5, 10, and 15 cm oral to the gastro-oesophageal sphincter and in the pharynx, and pH 5 cm oral to the sphincter. Peristalsis confined to the oesophagus was found to be related to the volume of the instilled fluid, whereas pharynx-mediated peristalsis seemed to be related to the acidity of the fluid. It is concluded that peristalsis after imitated gastro-oesophageal reflux is influenced by both the volume and the acidity of the instilled fluid. Volume seems to initiate a local clearing mechanism, whereas low pH initiates pharynx-mediated peristalsis.

Adult↗
PubMed1983

Thermography in the diagnosis of deep venous thrombosis. A comparison with 99Tcm-plasmin test, clinical diagnosis and phlebography.

Thermography, clinical examination and 99Tcm-plasmin test were performed in 112 patients and compared with phlebography. The study population consists of consecutive outpatients with symptoms compatible with deep venous thrombosis, who presented during regular clinic hours. Scoring systems were constructed for the clinical and thermographic evaluation. Both thermography and clinical diagnosis were insufficiently sensitive and specific for screening purposes. Plasmin test had a high sensitivity, 95%, but a low specificity. It is possible that a combination of thermography and clinical diagnostic criteria can provide an acceptable screening procedure. Combining thermography with a routine examination by the physician on duty yielded less favourable results.

False Negative Reactions↗