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T Skau

Publications and source records attributed to T Skau.

At least 19 recordsLinked to original sources
PubMed2005

A new probe for ankle systolic pressure measurement using photoplethysmography (PPG).

An automated method for ankle systolic pressure measurement, less operator dependent than the standard continuous wave (CW) Doppler technique, would imply an advantage both in patient measurements and in epidemiological studies. We present a new photoplethysmographic (PPG) probe that uses near-infrared light (880 nm) to detect pulsatory blood flow underneath the distal end of a standard pneumatic cuff. The probe is adapted to the anatomical conditions at the ankle, permitting recording of pressures in both ankle arteries separately. The validity of the equipment was tested with CW Doppler-derived systolic pressures and invasive blood pressure measurements for reference. In 20 healthy subjects, visual analysis of the PPG curves revealed a mean difference between CW Doppler and PPG measurements of -0.5 mmHg (SD 6.9). Corresponding results for the anterior and posterior tibial arteries separately were -1.8 mmHg (SD 6.2) and 0.9 mmHg (SD 7.3), respectively. A correct probe position was essential for the results. In direct recordings from the dorsalis pedis artery in 10 intensive care patients, PPG underestimated systolic pressure in the anterior tibial artery by 4.5 mmHg (SD 12.1). With further development, the PPG probe, integrated in the pneumatic cuff, may simplify measurements of ankle systolic pressures.

Adolescent↗
PubMed2005

Automatic ankle pressure measurements using PPG in ankle-brachial pressure index determination.

OBJECTIVE: To evaluate a new technique using a photoplethysmographic (PPG) probe for automatic ankle pressure measurements. DESIGN: Comparative study on two techniques for ankle pressure measurement. SETTING: University hospital. MATERIAL: Thirty-five patients with leg arterial disease and eight healthy volunteers. Ankle-brachial indices (ABPI) were measured using conventional CW Doppler technique and PPG-based prototype equipment for the ankle pressure recordings. CHIEF OUTCOME MEASURES: ABPIs calculated from CW Doppler and PPG ankle pressure measurements. The PPG signals were analysed both by visual judgement and by a software based, automatic algorithm. MAIN RESULTS: The mean difference between ABPIs calculated from CW Doppler recordings and PPG (visual analysis) was -0.01 (limits of agreement (+/-two standard deviations) +0.16 to -0.19). The correlation coefficient was 0.93. When the algorithm was used, the mean difference (CW Doppler-PPG) was 0.05 (limits of agreement 0.28 to -0.18, r=0.89). CONCLUSIONS: The PPG method is a promising technique with an inherent potential for automatisation of the ankle pressure measurements, thereby reducing the observer-dependency in ABPI recordings.

Adult↗
PubMed2002

Ankle-brachial index and mortality in a cohort of questionnaire recorded leg pain on walking.

OBJECTIVE: To study the association between the ankle-brachial pressure index (ABPI), premature death and the need for surgical treatment for lower limb ischaemia. DESIGN: Population based cohort study. SUBJECTS: Three hundred and fifty-three men and women, 50-89 years old, underwent a leg pain questionnaire and measurement of ABPI and was then followed for 10 years. OUTCOME MEASURES: All cause mortality, vascular procedures and major amputations. RESULTS: A low ABPI was independently associated with premature all cause mortality in the multiple regression analysis, carrying a relative risk of 3.4 (95% confidence interval 2.0-5.9) and 2.1 (1.3-3.3) for ABPIs or=1.0. Individuals with an ABPI in the interval 0.81-0.99 suffered only a slight, not statistically significant risk increase compared to normals. A low ABPI at baseline implied a continuous constant increased risk of death throughout the study period. The same risk was observed among elderly (70-89, median 77 years), and in the middle aged (50-69, median 63 years) individuals. The vast majority of those subjected to vascular intervention or major amputation during follow-up had an ABPI<or=0.8 at baseline (83 and 89%, respectively). However, within that group, the individual ABPI was not predictive for surgical intervention. CONCLUSION: The association found between an ABPI <or=0.8 and premature mortality in this cohort of symptomatic subjects implies that the ABPI is a powerful, independent predictor for premature death. The prognostic information carried by an ABPI in the interval 0.81-0.99 remains uncertain. Septuagenarians and octogenarians carry the same risk increase associated with a low ABPI as those in the middle ages.

Aged↗
PubMed2001

Is oscillometric ankle pressure reliable in leg vascular disease?

The objective of the study was to evaluate the validity of oscillometric systolic ankle pressure in symptomatic leg arterial occlusive disease. Ankle pressure measurements using oscillometric curves obtained using a standard 12-cm cuff with a specially designed device for signal processing were validated against the continuous wave (CW) Doppler technique. Thirty-four subjects without signs or symptoms of peripheral vascular disease (68 legs) and 47 patients with leg ischaemia (85 legs) varying from moderate claudication to critical ischaemia were examined. The oscillometric curves were analysed using several algorithms reported in the literature, based on the assumption that maximum oscillations are recorded near mean arterial pressure. In normals, reasonable agreement between CW Doppler and oscillometric methods was seen. When an algorithm that determined the lowest cuff pressure at which maximum oscillations occurred, and a characteristic ratio for systolic pressure of 0.52 was used, the mean difference between CW Doppler and oscillometry was 1.7 mmHg [range -19 to +27, limits of agreement (2 SD) 21.1 mmHg]. In ischaemic legs, oscillometry overestimated systolic ankle pressure by a mean of 28.8 mmHg [range -126 to +65, limits of agreement 82.8 mmHg]. The difference was more pronounced among patients with critical ischaemia compared with claudicants, and also more evident among diabetics. The error of oscillometric pressure determination in subjects with leg arterial disease inversely increased with CW Doppler ankle pressure. In 39% of the recordings in legs with a CW Doppler systolic pressure below 100 mmHg, the oscillometric mean arterial pressure was higher than the recorded CW Doppler systolic pressure. In conclusion, the oscillometric method to determine systolic ankle pressure, based on the concept of maximum cuff oscillations occurring near mean arterial pressure, is not reliable in leg arterial disease, usually overestimating ankle pressure.

Aged↗
PubMed1996

Outcome of symptomatic leg ischaemia: four year morbidity and mortality in Vadstena, Sweden.

OBJECTIVE: To quantify cardiovascular morbidity and mortality including the incidence of vascular surgery and amputations, among individuals with symptomatic leg ischaemia. DESIGN: Prospective cohort study. MATERIAL: Inhabitants 50-89 years of age (n = 2784) of Vadstena community, Ostergötland, Sweden, with 4 years of follow-up. 107 subjects with symptomatic leg ischaemia (SLI), selected by a postal questionnaire and ankle pressure measurements, and an age and sex matched control group of 214 individuals. CHIEF OUTCOME MEASURES: Cardiovascular morbidity and mortality, all cause mortality, surgical procedures for leg ischaemia, major amputations, ankle brachial pressure index. MAIN RESULTS: Age and sex adjusted all-cause mortality risk in the SLI-group was increased by 1.9. This was most prominent among men in their sixties and women in their seventies. Cardiovascular mortality was increased by 1.9 (95% confidence interval 1.1-3.3). Relative risks for acute myocardial infarction and cerebrovascular events were 2.4 (1.1-5.1) and 1.7 (0.9-3.2), respectively. The increase in age and sex adjusted incidence of primary reconstructive surgery during the first year after initial examination was 67-fold compared to the total population of Vadstena 50-89 years old, and 18 fold for the whole observation period, while the increase in risk for major amputation during the observation period was 12-fold. Median ankle brachial index improved significantly during follow-up among the individuals alive and not subjected to vascular surgery. CONCLUSIONS: Among the SLI-subjects identified in a general population, the overall risk for cardiovascular morbidity and mortality over 4 years was significantly increased compared to normals.

Age Distribution↗
PubMed1996

Biapenem versus imipenem/cilastatin in the treatment of complicated intra-abdominal infections: report from a Swedish Study Group.

118 patients with complicated intra-abdominal infections participated in an open randomized comparative multicenter trial in order to compare the clinical and microbiological efficacy and safety of biapenem with imipenem/cilastatin (Tienam). 31 men and 27 women (mean age 52.3 years) were enrolled in the biapenem group, and 43 men and 17 women (mean age 52.3 years) in the imipenem/cilastatin group. The patients received either biapenem 500 mg every 8 h or imipenem/cilastatin 500 mg/500 mg every 6 h by intravenous infusion for up to 13 days (mean 6.5 days). 28/43 evaluable patients (65.1%) receiving biapenem and 27/40 evaluable patients (67.5%) in the imipenem/cilastatin group were clinically cured. The microbiological response was satisfactory in 28/43 evaluable patients (65.1%) receiving biapenem and in 27/40 evaluable patients (67.5%) receiving imipenem/cilastatin. No significant differences in clinical or microbiological efficacy between the two treatment groups were found. The present study shows that biapenem may be useful in the treatment of intra-abdominal infections.

APACHE↗
PubMed1996

Does prophylactic treatment with felodipine, a calcium antagonist, prevent low-osmolar contrast-induced renal dysfunction in hydrated diabetic and nondiabetic patients with normal or moderately reduced renal function?

Twenty-seven patients (15 diabetics and 12 non-diabetics) with normal to moderately reduced renal function underwent femoral angiography with a low-osmolar contrast agent, iohexol (Omnipaque), under perexaminatory hydration. Fourteen patients were randomised to pretreatment with oral felodipine extended release (Plendil) 10 mg and 13 patients to placebo 3-4 h before angiography. GFR measured with [51Cr] EDTA-clearance decreased 24 hours after the angiography in the felodipine group from GFR 52.5 +/- 18.6 (mean +/- SD) to 46.2 +/- 16.5 ml/min (p < 0.01) and in the placebo group from 70.6 +/- 18.6 to 62.6 +/- 26.4 ml/min (p < 0.01). Serum creatinine increased significantly in the felodipine group from 128 +/- 61 to 139 +/- 67 mumol/l (p < 0.05) but not in the placebo group (122 +/- 54 to 125 +/- 51 mumol/l (ns)). The values of serum creatinine returned to baseline levels 7 days after angiography. During hydration there was only a slight reduction of GFR after angiography with iohexol. Thus, felodipine had no major effect on GFR after iohexol but, as baseline GFR tended to be lower in the felodipine pre-treated patients, it might have had some renoprotective effect in patients with more advanced renal failure.

Aged↗
PubMed1995

Meropenem versus imipenem/cilastatin in the treatment of intra-abdominal infections.

In order to compare the clinical and microbiological efficacy and safety of meropenem with imipenem/cilastatin, 249 patients with intra-abdominal infections participated in an open randomised comparative multicentre trial. Seventy-five men and 57 women (mean age 51 years) were enrolled in the meropenem group and 67 men and 50 women (mean age 52 years) in the imipenem/cilastatin group. The patients received either meropenem, 500 mg q 8 h, or imipenem/cilastatin, 500 mg/500 mg q 8 h by intravenous infusion for up to 17 days (mean 5 days). Ninety-seven of 99 patients (98%) receiving meropenem were clinically cured while 86 of 90 patients (96%) in the imipenem/cilastatin group were clinically cured. The microbiological response was satisfactory in 89 of 94 evaluable patients (95%) receiving meropenem and in 78 of 81 evaluable patients (96%) receiving imipenem/cilastatin. There was no significant difference in clinical and microbiological efficacy between the two treatment groups. Adverse reactions were noted in 26 patients receiving meropenem and in 36 patients receiving imipenem/cilastatin. The present study shows that meropenem is effective and well tolerated in the treatment of intra-abdominal infections.

APACHE↗
PubMed1993

Prevalence of symptomatic leg ischaemia in a Swedish community--an epidemiological study.

The prevalence of symptomatic leg ischaemia (SLI) was studied using a standardised postal questionnaire and by measuring ankle systolic blood pressure among those with leg pain. All individuals, aged 50-89 years, of both sexes (n = 2748) in a community of 7524 inhabitants were included. The overall questionnaire response rate was 92%, of whom 441 (17%) reported any form of leg pain. Ankle systolic blood pressure (ASBP) was measured in 353 (80%) of those. Ankle/brachial index (ABI) < or = 0.8 was chosen as the criterion for verified SLI. One hundred and seven (30%) had a verified SLI (ABI < or = 0.8). Hospital records could be reviewed in 83% of the non-responders, and revealed corresponding distributions of risk factors among the non-responders and the questionnaire-responders. Risk factor frequencies among ASBP-examined and not examined individuals were also comparable. The overall prevalence of SLI in the age 50-89 years was 4.1%, ranging from 1.5% in the age decade of 50-59 years, to maximum 7.1% in the decade 70-79 years. A slight but not significant male predominance was recorded, except for the age decade 70-79 years. The prevalence of SLI in the whole community population was approximately 2000/100,000 of which 5% were possible candidates for vascular intervention.

Aged↗
PubMed1993

Outcome of intra-abdominal infection in pigs depends more on host responses than on microbiology.

OBJECTIVE: To assess the effects of mortality of the presence and proliferation of bacteria, and the host's response to infection, in pigs with peritonitis. DESIGN: Laboratory study. SETTING: University hospital. MATERIAL: 71 Swedish Landrace pigs, 63 with peritonitis and 8 without (controls). INTERVENTIONS: Induction of peritonitis by intraperitoneal infusion of equal amounts of Escherichia coli and Bacteroides fragilis (10(9) to 10(11) bacteria/animal); sterile faeces were added in half the experiments. MAIN OUTCOME MEASURES: Microbiological events were quantified as the area under the bacterial concentration curve from 0-6 hours. Host responses were quantified with a score of 8 physiological variables measured between 4-6 hours after the induction of peritonitis. RESULTS: Of the 63 infected animals, 37 (59%) died within 6-24 hours and both the physiological response and the bacterial load were significantly higher in those that died. Logistic regression analysis with death as the dependent variable showed that the physiology score carried more predictive information than the quantification of bacterial load. CONCLUSION: The quantification of local events within the abdomen is of only limited predictive value compared with the extent of the physiological alterations.

Animals↗
PubMed1993

Effects of femoral arteriography and low osmolar contrast agents on renal function.

The contrast media-induced renal effects of 3 different low osmolar contrast agents were prospectively evaluated with creatinine, beta-2-microglobulin, and urea in serum before and after femoral arteriography in 110 consecutive patients. Forty-two patients (38%) had at least one of the 2 major risk factors for contrast media-induced nephropathy; diabetes mellitus or renal dysfunction. Six patients (5%) had both risk factors. There were statistically significant increases of S-creatinine (6.5%, p < 0.001) and S-beta-2-microglobulin (7.4%, p < 0.001) but no increase of S-urea, in the total patient material. This effect was independent of preexaminatory renal function, the presence of diabetes mellitus and type of low osmolar contrast agent used in these patients who were properly hydrated before the examination. The amount of administered contrast medium did not correlate with the degree of contrast agent-induced renal function impairment.

Acute Kidney Injury↗
PubMed1992

Piperacillin-tazobactam versus imipenem-cilastatin for treatment of intra-abdominal infections.

In order to compare the clinical and microbiological efficacies and safety of piperacillin plus tazobactam with those of imipenem plus cilastatin, 134 patients with intra-abdominal infections (73 patients with appendicitis) participated in an open randomized comparative multicenter trial. A total of 40 men and 29 women (mean age, 53 years; age range, 18 to 92 years) were enrolled in the piperacillin-tazobactam group and 40 men and 25 women (mean age, 54 years; age range, 16 to 91 years) were enrolled in the imipenem-cilastatin group. The patients received either piperacillin (4 g) and tazobactam (500 mg) every 8 h or imipenem and cilastatin (500 mg each) every 8 h. Both regimens were given by intravenous infusion. A total of 113 patients were clinically evaluable. Of 55 patients who received piperacillin-tazobactam, 50 were clinically cured, while 40 of 58 patients in the imipenem-cilastatin group were clinically cured. The differences were significant (Wilcoxon test; P = 0.005). There were 4 failures or relapses in the piperacillin-tazobactam group and 18 failures or relapses in the imipenem-cilastatin group. The microorganisms isolated were eradicated in similar proportions in the two patient groups. Adverse reactions, mainly gastrointestinal disturbances and nausea, were noted in 13 patients who received piperacillin-tazobactam and in 14 patients who received imipenem-cilastatin. Results of the present study show that piperacillin-tazobactam is effective and safe for the treatment of intra-abdominal infections.

Abdomen↗
PubMed1991

The dynamics of intraperitoneal growth and elimination of Escherichia coli and Bacteroides fragilis in porcine faecal peritonitis treated with fosfomycin.

The kinetics of intraperitoneal killing of proliferating bacteria was studied in pigs given fosfomycin. Eight animals were given intra-abdominal injection of Escherichia coli and Bacteroides fragilis (10(9) cfu of each species) mixed in sterile faces. Three hours later, half of the animals received an intravenous dose of 1 g fosfomycin (0.05 g/kg). Host defences rapidly decreased the density of E. coli in all animals in the first hour. After 2h, growth of E. coli started and continued throughout the experiment in pigs not receiving fosfomycin. B. fragilis was slowly eliminated in the first 5 6 h, then numbers increased in all animals. Fosfomycin caused a reduction in E. coli density, by 10(2.19) +/- 0.29 (mean +/- S.E.M.) cfu/ml, or more than 150 times within 1 h, while the concentration of B. fragilis was unaltered. After 10 h the difference in E. coli density between fosfomycin treated and untreated animals was 10(4.96) cfu/ml (P less than 0.01). Fosfomycin eradicated E. coli in faecal peritonitis but not B. fragilis, which is resistant in vitro. There was a prolonged elimination of the drug from peritoneal exudate in pigs infected with bacteria in sterile faeces compared to the elimination in uninfected pigs or pigs infected only with bacteria.

Animals↗