Sven-Göran Fransson

Individual variations of platelet inhibition after loading doses of clopidogrel

Abstract. Järemo P, Lindahl TL, Fransson SG, Richter A (Linköping University Hospital, Linköping, Sweden). Individual variations of platelet inhibition after loading doses of clopidogrel. J Intern Med 2002; 252: 233–238.

Oesophagitis, signs of reflux, and gastric acid secretion in patients with symptoms of gastro-oesophageal reflux disease.

In a study comprising 100 patients referred to a surgical clinic with symptoms suggestive of gastro-oesophageal reflux disease the value of different diagnostic procedures was investigated. Positive acid perfusion and 24-h pH tests were the commonest findings. Forty-nine per cent showed a normal oesophageal mucosa or diffuse oesophagitis at endoscopy. The severity of heartburn and regurgitation did not differ between patients with normal oesophageal mucosa and oesophagitis of various severities. The severity of macroscopic oesophagitis was significantly correlated to the total reflux time, the presence of reflux or a hiatal hernia at radiology, an open cardia or reflux at endoscopy, pressure transmission or reflux and low lower oesophageal sphincter pressure at manometry. Gastric hypersecretion was found in 66% of the patients. Gastric acid secretion was not correlated to the severity of oesophagitis or to the findings at 24-h pH test. In patients with severe oesophagitis the sensitivity for radiologic, manometric, and endoscopic signs of incompetence of the gastro-oesophageal junction was 94%.

Esophageal function, radiography, and dysphagia in Sjögren's syndrome

Esophageal function and anatomy were investigated with manometry, acid perfusion test, acid clearing test, and x-ray in 11 patients with primary Sjögrens syndrom (SS) and in 11 with secondary SS. The manometric investigation revealed minor motor differences in the SS patients as compared to 16 controls, ie, shorter peristaltic contraction time of the whole esophagus, and faster peristaltic velocity preferably in the distal part of the esophagus, while the results from the reflux tests did not differ between patients and controls. Radiographic examination revealed upper esophageal webs in 10% (2/20), and hiatal hernia in 25% (5/20). The dysphagia as reported by 73% of the patients cannot be explained by webs or impaired motor function and is regarded to be secondary to lack of saliva, making the solid bolus passage difficult.

Oesophageal reflux tests, manometry, endoscopy, biopsy, and radiology in healthy subjects

The aim was to study the exposure time of acid during 24 h at two different oesophageal levels in 15 healthy subjects and its relation to other kinds of oesophageal findings. Five centimetres above the lower oesophageal sphincter the total reflux time was 0.2% (0-1.3%), and at the 15-cm level it was 0.1% (0-0.7%). A standardized compression test during manometry and radiologic examination showed that no subject had reflux. Hiatus hernia was provoked at the radiologic examination in four subjects, one of whom also had a widened hiatus. At endoscopy, one subject had a hiatus hernia and slightly granulated oesophageal mucosa. Biopsy specimens showed slight basal cell hyperplasia in one case. Bleeding in the dermal papillae or a few intraepithelial leukocytes were seen in eight cases, findings that might be due to endoscopic trauma. Without any history of gastrointestinal disorders, gastrooesophageal reflux was minimal under standardized conditions, although hiatus hernia and mild changes in biopsy specimens could be seen.

Gastro-Oesophageal Reflux and Severity of Pulmonary Disease in Cystic Fibrosis

The correlation between oesophageal dysfunction (OD), pathologic gastro-oesophageal reflux (GOR), and severity of pulmonary disease was studied in 12 patients with cystic fibrosis (CF). They were interviewed about symptoms of OD and underwent 24-h pH recording in the oesophagus, oesophageal manometry combined with reflux provocation tests, the acid perfusion test, the acid clearance test, lung function tests, and scoring of the chest radiograph. Six of the 12 patients reported symptoms of OD. Abnormal GOR, as shown by 24-h pH monitoring of the oesophagus, was found in eight of them. Altogether 9 of the 12 participants had at least one pathologic oesophagus test result. Results of radiologic examinations of the oesophagus, performed in six patients, were pathologic. The four patients with the best chest radiograph scores and the best lung function had significantly less signs and symptoms of OD and GOR than the other eight patients. We conclude that OD, GOR, and pulmonary disease covariate in CF.

Immediate and late adverse reactions in coronary angiography. A comparison between iodixanol and ioxaglate.

Purpose and Methods: In 120 patients in a double-blind, randomized, parallel study, iodixanol (Visipaque), a nonionic dimer isotonic with blood, was compared with ioxaglate (Hexabrix), an ionic low-osmolar dimer, in coronary angiography regarding early and late adverse reactions. Haemodynamic and electrophysiologic parameters were also analyzed. Results: Visipaque resulted in significantly fewer early adverse contrast medium-related reactions (p<0.05). Visipaque also demonstrated significantly fewer effects on electrophysiologic parameters. Both contrast media reduced systolic and diastolic blood pressures at the 1st injection in the left coronary artery. Late adverse reactions were unusual with both contrast media and occurred only as urticaria with a frequency of 1.7%, which is lower than reported in i.v. studies. One serious adverse reaction, a myocardial infarction in a male patient with severe cardiovascular disease, occurred in the Visipaque group. This event was considered to be procedure- and disease-related rather than related to the type of contrast medium used. Conclusion: We found Visipaque safe for coronary angiography, causing fewer early adverse reactions than Hexabrix and also fewer effects on electrophysiologic parameters. Late adverse reactions seemed to be unusual with intra-arterial administration of contrast media.

Calf Compression for Prevention of Thromboembolism Following Hip Surgery

A prospective, randomized trial of the effect of graded compression of the calf was done in 62 patients operated on electively for hip disease. After total hip arthroplasty, compression reduced the number of positive fibrinogen uptake tests by two-thirds, significant only in males, who seem to run a higher risk of thrombosis than females.

A comparison of analogue and digital techniques in upper gastrointestinal examinations : absorbed dose and diagnostic quality of the images.

Abstract. This study was performed to investigate whether patient exposure and diagnostic quality of the image is significantly influenced by the introduction of digital image acquisition techniques. Evaluation was performed for three different techniques (analogue, analogue fluoro + digital radiography, digital) in examination of the upper gastrointestinal tract. The evaluation was done from data acquired in three different departments. Patient exposure was recorded as KERMA-area product (KAP) and the individual patient readings were normalised to a standard size patient. Image quality was assessed using visual grading with a reference image. The recorded KAP values were significantly higher (22.3 Gycm2) for the fully digital technique compared to the others (analogue 6.8 Gycm2, analogue + digital 3.6 Gycm2). This was due mostly to an increased number of exposures. The diagnostic quality of the image was, however, also regarded to be slightly lower for the technique giving the lowest patient dose with the smallest number of exposures (analogue + digital). The digital examination technique, as used in this study, thus resulted in significantly higher patient dose without any significant gain in diagnostic quality of the image.

Atelectasis and oxygenation in major surgery with either propofol with or without nitrous oxide or isoflurane anaesthesia

Forty‐two patients undergoing major colonic surgery were assigned at random to receive isoflurane‐fentanyl anaesthesia with nitrous oxide in oxygen, propofol‐fentanyl anaesthesia with air in oxygen or propofol‐fentanyl anaesthesia with nitrous oxide in oxygen. The groups were comparable in demographic data. Atelectases were identified, and the area measured by computerised tomography of the chest 203±69 min after extubation. and oxygenation was determined by arterial blood gas samples taken during operation at 30, 60, 90 and 120 min after extubation and on postoperative days 1, 2 and 3. Atelectases were seen in all three groups with no differences in the mean area between groups. After operation, the effect of 4 l.min−1 of oxygen by nasal catheter on Pao2 was similar in all groups. A significant decrease in PaO2 was found during the first 3 days after surgery, and was also the same in all groups. There was no correlation between area of atelectasis and postoperative PaO2. We conclude there is no difference in the incidence of postoperative atelectasis or oxygenation when using propofol, with or without nitrous oxide or isoflurane.

Inverse relationship between platelet density and reactivity alterations at coronary angiography

This work investigates relationships between platelet density and reactivity. 21 individuals subject to coronary angiography were studied. Peak platelet density was analyzed using a newly developed electronic device. The apparatus measures light transmission through test tubes containing density-separated platelets, thus allowing an estimation of the platelet distribution in the gradient. A flow cytometry technique was used for determining platelet reactivity after stimulating with ADP. Platelet counts, mean platelet volumes, peak platelet density and platelet reactivity were determined immediately before (day 1) and 24 h after cardiac catheterization (day 2). For all parameters changes during the day of angiography were compared with platelet density alterations. The subjects were divided into two groups according to density changes at angiography. Group 1 individuals showed density alterations (i.e. day 2 – day 1 value) ≧–8 × 10–5 kg/l. In contrast, group 2 subjects either displayed density changes <–8 × 10–5 kg/l or grossly disturbed platelet density patterns on day 2. Before angiography both groups had similar platelet counts and volumes. Then platelet reactivity when stimulating with ADP did not differ significantly between the two groups. After angiography, the number of fibrinogen-positive cells when stimulating with ADP rose by 6 ± 8% for group 2 patients. The corresponding figure for group 1 was –1 ± 6%. The difference was significant (p = 0.01). No such relationships were found when comparing density alterations and changes of platelet counts and volumes. We conclude that in this study platelet density alterations at coronary angiography are inversely related to variations of platelet reactivity.