Effect of time delay and storage temperature on blood gas and acid ...

122 G. Gokce et al. / Research in Veterinary Science 76 (2004) 121–127dependent (Liss <strong>and</strong> Payne, 1993). Additionally, severeleucocytosis (Schimidt <strong>and</strong> Plathe, 1992; Liss <strong>and</strong> Payne,1993) <strong>and</strong> anaemia (Haskins, 1977) can lead to alterationsin acid–base values.Since it is difficult to measure the acid–base <strong>and</strong> gasvalues <strong>of</strong> blood under field conditions in a short period<strong>of</strong> <strong>time</strong> its necessary to store blood (Szenci <strong>and</strong> Besser,1990). Several authors have investigated the alterationsin acid–base variables during the <strong>storage</strong> <strong>of</strong> bloodsamples from humans (Paerregaard et al., 1987; Schimidt<strong>and</strong> Plathe, 1992; Beaulieu et al., 1999), cattle(Jagos et al., 1977; Poulsen <strong>and</strong> Surynek, 1977; Krokavecet al., 1987; Szenci <strong>and</strong> Besser, 1990; Szenci et al.,1991, 1994) <strong>and</strong> dogs (Haskins, 1977). It would be usefulto determine the extent to which changes in blood acid–base values <strong>and</strong> gas composition depend on the duration<strong>and</strong> <strong>temperature</strong> <strong>of</strong> <strong>storage</strong>. To our knowledge, there isno precise information available as to whether or notclinically significant changes occur when bovine venousblood is stored at 22 or at 37 °C for long periods.Therefore, this study was carried out to detect thechanges in gas composition <strong>and</strong> acid–base values inbovine venous blood samples stored at different <strong>temperature</strong>s(+4, 22 <strong>and</strong> 37 °C) for up to 48 h.2. Materials <strong>and</strong> methods2.1. Animals <strong>and</strong> samplingFive clinically healthy, 1–3 years old, crossbreedcattle were used in the study. Following rectal <strong>temperature</strong>measurement, three jugular venous blood sampleswere drawn from each animal into 10 ml plastic syringesthe dead space (0.08 ml) <strong>of</strong> which was filled with heparin(Liquemine Ò -Roche, Istanbul, Turkey). The needle tipswere closed with a rubber stopper after the removal <strong>of</strong>air bubbles from the samples. The samples were placedin a bed <strong>of</strong> crushed ice, taken immediately to the laboratory<strong>and</strong> analysed within 15 min. Following the first(0) hourÕs laboratory analysis, a total <strong>of</strong> 15 blood sampleswere collected from the animals, allocated into threegroups <strong>and</strong> then stored, respectively, in a refrigerator setto +4 °C (Group I, n ¼ 5), at a room <strong>temperature</strong> <strong>of</strong>about 22 °C (Group II, n ¼ 5) <strong>and</strong> in an incubator adjustedto 37 °C (Group III, n ¼ 5), for up to 48 h. Bloodgas <strong>and</strong> acid–base values were analysed at 0, 1, 2, 3, 4, 5,6, 12, 24, 36 <strong>and</strong> 48 h <strong>of</strong> <strong>storage</strong> for all the groups.2.2. Acid–base <strong>and</strong> blood gas analysesThe measurement <strong>of</strong> pH, pO 2 , pCO 2 <strong>and</strong> the calculation<strong>of</strong> st<strong>and</strong>ard Base excess (BEstd), actual base excess(BEact), st<strong>and</strong>ard bicarbonate (stHCO 3 ), actualbicarbonate (actHCO 3 ) concentrations, oxygen saturation(O 2 SAT) <strong>and</strong> oxygen content (O 2 CT) were automaticallyperformed on a blood gas analyser (Chirondiagnostics, Rapidlab 248, UK) prior to the study.Blood samples from the five cattle were analysed forblood gas <strong>and</strong> acid base values four <strong>time</strong>s each within 15min to determine the imprecision <strong>of</strong> parameters, whichemerged as follows: pH 0.01%; pCO 2 1.9%; pO 2 3.52%;ActHCO 3 1.74%; StdHCO 3 1.34%, BEact 1.98%, BEstd1.02%, O 2 SAT 0.39% <strong>and</strong> O 2 CT 1.8% on the basis <strong>of</strong>variation co efficiency. Control <strong>of</strong> accuracy was carriedout using a commercial accuracy control solution(Complete, Bayer, East Walpole, USA). Control valueswere within the normal range as described by the manufacturer.Calculated variables were automatically performedby blood gas analyser according to equations 1programed to device by manufacterer (Chiron diagnostics,Rapidlab 248, UK) The values <strong>of</strong> pH, pCO 2 <strong>and</strong>pO 2 were automatically adjusted to the animalÕs rectal<strong>temperature</strong>s.2.3. Haematological analysesFor the initial haematological examinations, peripheralblood samples were collected from jugular vein intoethylenediaminetetraaceticacid (EDTA) treated tubes.These blood samples were used to manually establishtotal white blood cells (WBCs), total red blood cells(RBCs) <strong>and</strong> haemoglobin concentration (Hb), as describedby Coles (1980).2.4. Statistical analysesThe effect <strong>of</strong> <strong>temperature</strong> on blood gas <strong>and</strong> acid basevalues was tested by analysis <strong>of</strong> variance using SPSS forWindows 6.0. The effects <strong>of</strong> <strong>time</strong> on the repeated measurementswithin each group were also examined usingtwo-way variance analysis (Kirkwood, 1988). The datais presented as mean SE.3. ResultsThe mean initial haematological values <strong>of</strong> the animalsused in the study were detected as 115 0.6 g/l for Hb,5.9 0.5 10 12 cell/l for RBC <strong>and</strong> 6.5 1.9 10 9 cell/lfor WBC. The mean rectal <strong>temperature</strong> <strong>of</strong> the animalswas 38.5 0.2 °C.1 ActHCO 3 ¼ pH þ logðpCO 2 0:0307Þ 6:105; StdHCO 3 ¼ 24:5þ0:9A þðA 2:9Þ 2 ð2:65 þ 0:31ctHbÞ=1000. A ¼ BEstd 0:2½ctHbŠ½100 O 2 SATŠ=100; BEact ¼ cHCO 3 24:8 þ 1:62ðpH 7:40Þ.BEstd ¼ð1 0:014 ctHbÞ½ðcHCO 3 24:8Þ þð1:43 ctHb þ 7:7ÞðpH 7:40Þ.N 4 15N 3 þ 2045N 2 þ 2000NO 2 SAT ¼N 4 15N 3 þ 2400N 2 31100N þ 2:4 10 100:6N ¼ pO 2 þ 10 ½0:48ðpH 7:4Þ 0:0013BEstdŠ <strong>and</strong> BEstd is calculated assuming100% O 2 SAT; O 2 CT ¼ O 2 SAT 1:39 ctHb þ 0:00314 pO 2 .