Bergqvist D

Does low-dose acetylsalicylic acid prevent stroke after carotid surgery? A double-blind, placebo-controlled randomized trial.

Background and Purpose The aim of this randomized double-blind, placebo-controlled trial was to evaluate whether neurological deficits could be prevented with low-dose acetylsalicylic acid (ASA) as an adjunct to carotid endarterectomy. Methods A total of 232 patients were randomized to two groups, 75 mg/d ASA starting preoperatively and continued for 6 months (n=117) or placebo (identical tablets) (n=115). The patients were followed up regularly for 1 year. Results The groups were well matched regarding laboratory data and indication for operation. The number of patients with intraoperative or postoperative stroke without complete recovery within 1 week were 0 and 2 at 30 days and 6 months, respectively, in the ASA group, compared with 7 and 11 in the placebo group (P=.01). Including all neurological events within 6 months, this was found in 15 patients in the ASA group compared with 24 in the placebo group (P=.12). Mortality was 0.8% and 3.4% at 30 days and 6 months, respectively, in the ASA group. In the placebo group, the corresponding figures were 4.3% and 6.0%, respectively (P=.12). The intraoperative bleeding did not differ between the groups nor did the number of reoperations due to bleeding or other complications related to pharmacology. Conclusions This study indicates that low-dose ASA (75 mg/d) reduces the number of postoperative strokes without complete recovery within 1 week. Overall neurological events are insignificantly reduced, as also mortality. The use of low-dose ASA (75 mg) seems safe and effective in reducing cerebrovascular events after carotid endarterectomy.

Low molecular weight heparin for thromboprophylaxis and epidural/spinal anaesthesia--is there a risk?

This article reviews the problem of bleeding in connection with epidural/spinal anaesthesia, with special emphasis on the use of low molecular weight heparins for thromboprophylaxis. There are methodological difficulties to studying the problem in a scientifically correct way because of the rarity of the complication. However, from the data in the literature there are no indications of an increased risk in using the combination of low molecular weight heparin in prophylactic doses and epidural/spinal anaesthesia. So far, there is only a single case report, of spinal haematoma, although low molecular weight heparins have been used in combination with epidural/spinal anaesthesia in at least 1000000 patients. In controlled studies, at least 10000 patients have been given the combination without complications.

Abdominal injuries in children: an analysis of 348 cases

Three hundred and forty-eight children from Skaraborg County, Sweden, admitted to hospital with abdominal injuries over a 30-year period (1951-1980), have been analysed and compared with all patients with abdominal injury (1407) admitted to hospital from the same area during the same period. The number of children admitted in the second half of the period was greater than during the first but the proportion of children compared with adults was considerably reduced. During the period abdominal injuries due to car accidents increased in adults but not in children. The most frequent cause of abdominal injury in children was a bicycle accident. Abdominal injury due to sport also increased over the period. Mortality decreased, with no deaths in the past 10 years, compared with 8.6 per cent mortality in the first 10 years of the period.

Abdominal injury from sporting activities

The frequency of abdominal injury is rising. In an analysis of 1,354 cases of closed abdominal trauma sustained during a 30-year period (1950-1979) in Skaraborg County, Sweden, a distinct increase was found in the numbers associated with sporting activities. The severity of the injuries caused by sports likewise showed an increase. The representation of injured organs was of the same order as in the total series of closed abdominal injuries. An analysis of the 136 cases of sports-associated injury is presented with regard to cause and type of the injuries, diagnosis and prognosis.

Regional differences in mechanical properties between major arteries--an experimental study in sheep.

PURPOSE To study possible differences in mechanical properties between central (abdominal aorta) and more peripheral (common carotid and common femoral) arteries validating an earlier non-invasive study in children showing that central arteries are more distensible than peripheral ones. As invasive blood pressure was needed, but ethically impossible to obtain in children in an experimental setting, an animal model was chosen. DESIGN Open experimental study. SETTING Animal laboratory at university hospital. MATERIAL AND METHODS The pulsatile vessel wall movements of the abdominal aorta (AA), common femoral (CFA) and common carotid (CCA) artery of nine sheep were examined using an ultrasound phase-locked echo-tracking technique. Intra-arterial blood pressure was measured and pressure-diameter relations, pressure strain elastic modulus (Ep) and stiffness (beta) calculated. Distensibility was defined as the inverse of Ep and stiffness. RESULTS The AA showed lower values for Ep and stiffness (beta) than the CFA (p = 0.002) and CCA (p = 0.006), i.e. the latter two vessels were stiffer. The pressure-diameter relations confirmed these differences and showed a non-linearity for all three vessels with increased stiffness above 70-90 mm Hg. CONCLUSION This study on young animals supports earlier findings of differences in mechanical properties between central and more peripheral arteries seen in healthy children. As pathologies between these vessels differ, with dilatation of the abdominal aorta and occlusive disease in the more peripheral vessels, part of the explanation might be found in the mechanical properties of the healthy vessels, characterised here with the echo-tracking technique.

Pharmacokinetics of a low molecular weight heparin, Logiparin, after intravenous and subcutaneous administration to healthy volunteers

In six healthy volunteers we have estimated the pharmacokinetic parameters of the anti factor Xa (AXa) and anti factor IIa (AIIa) activities of a LMW heparin, Logiparin. For the AXa the following parameters were estimated in a 1-compartment model (mean and 95% confidence limits in brackets): elimination half life 82 minutes (60-127 min), absorption half life (s.c. inj.) 200 minutes (137-368 min), bioavailability 90% (24-156%), and apparent volume of distribution 3.9 l (3.1-5.2 l). The plasma activity was linearly correlated to the dose given and to the body weight of the volunteer. For the AIIa the parameters estimated in a 1-compartment model were: elimination half life 71 minutes (52-115 min), absorption half life 257 minutes (133-3442 min), bioavailability 67% (44-90%), and apparent volume of distribution 10.1 l (7.2-16.7 l). The plasma activity was dependent on dose and body weight but it also seemed to be influenced by individual factors. This study shows that the absorption rate is the rate limiting factor and the explanation for the long lasting effect of this LMW heparin after subcutaneous injection. The slow absorption rate and the high bioavailability are probably the major advantages of LMW heparins compared to conventional heparin.

No transplacental passage of standard heparin or an enzymatically depolymerized low molecular weight heparin.

In 21 women who had an abortion by hysterotomy between the 15th and 23rd week of pregnancy, the possibility that unfragmented heparin or low molecular weight heparin (LMWH) passed the placental barrier to the foetus was studied. Laboratory analyses included amidolytic assays of factor Xa inhibitory activity (XaI), antithrombin III (ATIII) and a direct measurement of heparin-like substances in plasma with a competitive binding assay. The ATIII concentration in foetal plasma was about 20% of that in normal human plasma and varied considerably between individuals (2–27%). The XaI activity did not differ between the two treated groups, but the mean XaI activity of the combined groups differed from zero (P < 0.05). If the XaI activity was corrected for the ATM concentration, the heparin activities no longer differed significantly from zero. As die concentration of heparin-tike substances were above the detection limit (0.35 μg/ml) in 6/16 analysable samples of foetal plasma, a further 15 women who had not received any heparin were included as controls. In 12/14 analysable foetal plasmas heparin-like substances in concentrations above 0.35 μg/ml could be detected. Determination of heparin activity in foetal plasma is thus difficult due to the influence of endogenous ATIII on heparin assays. In conclusion, this study did not demonstrate any evidence for the passage of heparin or LMWH across the placental barrier. No differences were detected whether unfragmented heparin or LMWH had been given to the mothers. Our results also indicate the presence of an endogenous glycosaminoglycan in foetal plasma.

Patients with abdominal trauma and fatal outcome: analysis of a 30-year series

Patients with blunt abdominal trauma and fatal outcome during 30 years in a well-defined rural Swedish area have been analyzed. There were 127 patients. Several facts indicate that more severe trauma has been appearing more often during this period The mortality rate has, however, been stable, but the patients have become older. More patients die from pulmonary complications than from the trauma itself. One very important development is the significant decrease in mortality among children.

Blunt renal trauma. Analysis of 417 patients

Case records of 417 patients, from a well-defined area, who were hospitalized because of blunt renal trauma during the period 1950-1979 were analyzed. The incidence increased during the final decade, corresponding to a rising incidence of motor traffic accidents and sports injuries. Young patients, between 10 and 29 years of age, were responsible for the increase and half of all patients were in this age group. Associated injuries were frequent. Emergency urography was rare during the earlier part of the investigation period, but the frequency increased strongly thereafter. Treatment was mainly conservative (nonoperative) except in patients with major renal injuries. Nephrectomy was performed in 22 patients. Reconstructive surgery was performed especially in patients with intermediate renal injuries during the final decade. The total mortality was 6.5%. Only 7 patients (1.7%) died from the renal injury. A dramatic reduction in the hospitalization time was noted.

Intraplaque haemorrhage at carotid artery surgery--a predictor of cardiovascular mortality.

Abstract. Objective. To ascertain whether carotid intraplaque haemorrhage (IH) in patients undergoing carotid artery surgery is a predictor of increased cardiac mortality over a 5.5 year follow‐up.