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Bergek, Christian
Publications (4 of 4) Show all publications
Zdolsek, J., Bergek, C., Lindahl, T. & Hahn, R. (2015). Colloid osmotic pressure and extravasation of plasma proteins following infusion of Ringers acetate and hydroxyethyl starch 130/0.4. Acta Anaesthesiologica Scandinavica, 59(10), 1303-1310
Open this publication in new window or tab >>Colloid osmotic pressure and extravasation of plasma proteins following infusion of Ringers acetate and hydroxyethyl starch 130/0.4
2015 (English)In: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 59, no 10, p. 1303-1310Article in journal (Refereed) Published
Abstract [en]

BackgroundDuring fluid infusion therapy, plasma proteins are diluted and leak from the intravascular space, which alters the colloid osmotic pressure (COP) and potentially affects coagulation. We hypothesised that acetated Ringers and starch solution, alone or in combination, influence these mechanisms differently. Materials and methodsOn different occasions, 10 male volunteers were infused with 20ml/kg acetated Ringers and 10ml/kg 6% hyroxyethyl starch 130/0.4 (Voluven((R))) alone or in combination (first with starch solution followed by Ringers solution). Blood samples were collected every 30-min for measurements of COP, blood haemoglobin, platelets, and plasma concentrations of albumin, immunoglobulins (IgG and IgM), coagulation factor VII (FVII), fibrinogen, cystatin C, activated partial thromboplastin time (APTT) and prothrombin international normalised ratio (PT-INR). Changes were compared with the haemoglobin-derived plasma dilution. ResultsThe COP increased by 8.4% (SD 3) with starch and decreased by 26.2% (7.9) with Ringers. These infusions diluted the plasma by 23.4% (5.3) and 18.7% (4.9) respectively. The COP changes in the combined experiment followed the same pattern as the individual infusions. Albumin and IgG changes in excess of the plasma dilution were very subtle. The intravascular contents of the IgM and platelets decreased, whereas FVII, fibrinogen and cystatin C increased. PT-INR increased by 1/3 of the plasma dilution, whereas changes in APTT did not correlate with the plasma dilution. ConclusionsThe starch increased COP and only minor capillary leak occurred in healthy volunteers. The fluid-induced plasma dilution correlated with mild impairment of the extrinsic coagulation pathway but not of the intrinsic pathway.

Place, publisher, year, edition, pages
National Category
Clinical Medicine
urn:nbn:se:liu:diva-122412 (URN)10.1111/aas.12558 (DOI)000362589100010 ()26079310 (PubMedID)

Funding Agencies|Stockholm City Council [20070421]; Ostergotland County Council [156791]

Available from: 2015-11-02 Created: 2015-11-02 Last updated: 2017-12-01
Bergek, C., Zdolsek, J. H. & Hahn, R. (2015). Non-invasive blood haemoglobin and plethysmographic variability index during brachial plexus block. British Journal of Anaesthesia, 114(5), 812-817
Open this publication in new window or tab >>Non-invasive blood haemoglobin and plethysmographic variability index during brachial plexus block
2015 (English)In: British Journal of Anaesthesia, ISSN 0007-0912, E-ISSN 1471-6771, Vol. 114, no 5, p. 812-817Article in journal (Refereed) Published
Abstract [en]

Background Plethysmographic measurement of haemoglobin concentration (SpHb  ), pleth variability index (PVI), and perfusion index (PI) with the Radical-7 apparatus is growing in popularity. Previous studies have indicated that SpHb  has poor precision, particularly when PI is low. We wanted to study the effects of a sympathetic block on these measurements.

Methods Twenty patients underwent hand surgery under brachial plexus block with one Radical-7 applied to each arm. Measurements were taken up to 20 min after the block had been initiated. Venous blood samples were also drawn from the non-blocked arm.

Results During the last 10 min of the study, SpHb  had increased by 8.6%. The PVI decreased by 54%, and PI increased by 188% in the blocked arm (median values). All these changes were statistically significant. In the non-blocked arm, these parameters did not change significantly.

Conclusions Brachial plexus block significantly altered SpHb  , PVI, and PI, which indicates that regional nervous control of the arm greatly affects plethysmographic measurements obtained by the Radical-7. After the brachial plexus block, SpHb  increased and PVI decreased.

Place, publisher, year, edition, pages
Oxford University Press (OUP): Policy B - Oxford Open Option B, 2015
haemoglobinometry; nerve blockade; perfusion; photoplethysmography; vasodilation
National Category
Anesthesiology and Intensive Care
urn:nbn:se:liu:diva-118861 (URN)10.1093/bja/aeu484 (DOI)000354153500015 ()25603961 (PubMedID)
Available from: 2015-06-08 Created: 2015-06-04 Last updated: 2017-12-04
Hahn, R., Bergek, C., Gebäck, T. & Zdolsek, J. (2013). Interactions between the volume effects of hydroxyethyl starch 130/0.4 and Ringer´s acetate. Critical Care, 17(3)
Open this publication in new window or tab >>Interactions between the volume effects of hydroxyethyl starch 130/0.4 and Ringer´s acetate
2013 (English)In: Critical Care, ISSN 1466-609X, Vol. 17, no 3Article in journal (Refereed) Published
Abstract [en]


The turnover of Ringer´s solutions is greatly dependent on the physiological situation, such as the presence of dehydration or anaesthesia. The present study evaluates whether the kinetics is affected by previous infusion of colloid fluid.


Ten male volunteers with a mean age of 22 years underwent three infusion experiments, on separate days and in random order. The experiments included 10 mL/kg of 6% hydroxyethyl starch 130/0.4 (Voluven™), 20 mL/kg of Ringer's acetate, and a combination of both, where Ringer´s was administered 75 minutes after the starch infusion ended. The kinetics of the volume expansion was analysed by non-linear least- squares regression, based on urinary excretion and serial measurement of blood haemoglobin concentration for up to 420 minutes.


The mean volume of distribution of the starch was 3.12 L which agreed well with the plasma volume (3.14 L) estimated by anthropometry. The volume expansion following the infusion of starch showed monoexponential elimination kinetics with a half-life of two hours. Two interaction effects were found when Ringer´s acetate was infused after the starch. First, there was a higher tendency for Ringer´s acetate to distribute to a peripheral compartment at the expense of the plasma volume expansion. The translocated amount of Ringer´s was 70% higher when HES had been infused earlier. Second, the elimination half-life of Ringer´s acetate was five times longer when administered after the starch (88 versus 497 minutes, P <0.02).


Starch promoted peripheral accumulation of the later infused Ringer´s acetate solution and markedly prolonged the elimination half-life.

Place, publisher, year, edition, pages
BioMed Central, 2013
National Category
Medical and Health Sciences
urn:nbn:se:liu:diva-100144 (URN)10.1186/cc12749 (DOI)000329431100021 ()23718743 (PubMedID)
Available from: 2013-10-29 Created: 2013-10-29 Last updated: 2014-02-19Bibliographically approved
Bergek, C., Zdolsek, J. & Hahn, R. G. (2012). Accuracy of noninvasive haemoglobin measurement by pulse oximetry depends on the type of infusion fluid. European Journal of Anaesthesiology, 29(12), 586-592
Open this publication in new window or tab >>Accuracy of noninvasive haemoglobin measurement by pulse oximetry depends on the type of infusion fluid
2012 (English)In: European Journal of Anaesthesiology, ISSN 0265-0215, E-ISSN 1365-2346, Vol. 29, no 12, p. 586-592Article in journal (Refereed) Published
Abstract [en]

Context: Measurement of blood haemoglobin concentration by pulse oximetry could be of value in determining when erythrocytes should be transfused during surgery, but the effect of infusion fluids on the results is unclear.

Objective: To study the effect of crystalloid and colloid fluid on the accuracy (bias) and precision of pulse oximetry haemoglobin estimation to indicate the venous haemoglobin concentration in volunteers.

Design: Open interventional crossover study.

Setting: Single university hospital.

Participants: Ten male volunteers aged 18–28 (mean 22) years.

Interventions: Each volunteer underwent three infusion experiments on separate days and in random order. The infusions were Ringer's acetate (20 ml kg−1), hydroxyethyl starch 130/0.4 (10 ml kg−1) and a combination of both.

Results: At the end of the infusions of Ringer's acetate, pulse oximetry haemoglobin concentration had decreased more than the true haemoglobin concentration (15 vs. 8%; P < 0.005; n  = 10) whereas starch solution decreased pulse oximetry haemoglobin concentration less than true haemoglobin concentration (7 vs. 11%; P < 0.02; n  = 20). The same differences were seen when the fluids were infused separately and when they were combined. The overall difference between all 956 pairs of pulse oximetry haemoglobin concentration and true haemoglobin concentrations (the bias) averaged only −0.7 g l−1 whereas the 95% prediction interval was wide, ranging from −24.9 to 23.7 g l−1. In addition to the choice of infusion fluid, the bias was strongly dependent on the volunteer (each factor, P < 0.001).

Conclusion: The bias of measuring haemoglobin concentration by pulse oximetry is dependent on whether a crystalloid or a colloid fluid is infused.

Place, publisher, year, edition, pages
Lippincott Williams & Wilkins, 2012
colloid, crystalloid, haemoglobin, pulse oximetry
National Category
Medical and Health Sciences
urn:nbn:se:liu:diva-86624 (URN)10.1097/EJA.0b013e3283592733 (DOI)000310923700007 ()

Funding Agencies|Stockholm City Council||Ostergotland County Council||

The publication has been published twice by the journal. It is also included in volyme 30, issue 2, pages 73-79 (February 2013).

Available from: 2013-04-22 Created: 2012-12-20 Last updated: 2017-12-06Bibliographically approved

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