Dynamics of the acid-base balance of venous and arterial blood in clinically healthy calves]

Values of the acid base balance were examined in both venous and arterial blood of healthy calves (n = 6) of the Slovak Spotted breed aged, 3, 6, 8, 10, 12, 14, 18, and 24 weeks, respectively. Until week 4 of age the animals were fed milk only, until the age of 9 weeks a milk-roughage transition fodder and from week 10 on they were given classical herbage. Blood samples were taken from the V. jugularis and A. carotis communis or A. axillaris, respectively. The results achieved were corrected to a body temperature of 39 degrees C. During the examination period the following values were stated for both arterial and venous blood: actual acidity (pH) 7.391 +/- 0.014 and 7.362 +/- 0.013 logmolc, pCO2 6.35 +/- 0.15 and 7.35 +/- 0.11 kPa, HCO3-28.38 +/- 1.42 and 30.32 +/- 1.02 mmol. l(-1), ABE 3.57 +/- 1.44 and 4.34 +/- 1.09 mmol. l(-1); pO2 12.63 +/- 1.15 and 5.21 +/- 0.73 kPa, SAT 95.8 +/- 1.03 and 61.2 +/- 9.59%, respectively. A gradual increase in most indices of the acid base balance could be stated both in arterial and venous blood. The trends either revealed a parallel increase (HCO3-, pH) or they were more pronounced either in venous blood (SAT) or in arterial blood (ABE, pO2). Some trends were almost balanced (pCO2 and pO2 in venous blood and SAT and pCO2 in arterial blood). Thus pH, pO2 and SAT indices of the acid base balance were higher in arterial blood as compared to venous blood while pCO2, HCO3- and ABE values were higher in venous blood.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of ventral coccygeal arterial and jugular venous blood samples for pH, pCO2, HCO3, Be(ecf) and ctCO2 values in calves with pulmonary diseases

The aim of this study was to determine whether venous blood samples can be used as an alternative to arterial samples in calves with respiratory problems and healthy calves. Jugular vein and ventral coccygeal artery were used to compare blood gas values. Sampling of the jugular vein followed soon after sampling of the ventral coccygeal artery in healthy calves (group I) and calves with respiratory problems (group II). Mean values of arterial blood for pH, pCO2, HCO3act in healthy calves were 7.475 +/- 0.004, 4.84 +/- 0.2 kPa, 28.45 +/- 1.30 mmol/L compared with venous samples, 7.442 +/- 0.006, 6 +/- 0.3 kPa, 30.93 +/- 1.36 mmol/L, respectively. In group II, these parameters were 7.414 +/- 0.01, 5.93 +/- 0.3, 27.73 +/- 1.96 mmol/L for arterial blood and 7.398 +/- 0.008, 6.85 +/- 0.2 kPa, 29.77 +/- 1.91 mmol/L for venous blood, respectively. There were no statistically significant differences between arterial and venous pH, HCO3act, Be(ecf), ctCO2 values with the exception of pCO2 (P = 0.001) in group II. In group I, correlation (r2) between arterial and venous blood pH, pCO2, HCO3act were 84.5%, 87.5%, 95.7%, respectively compared with the same parameters in group II, 80.8%, 77.1%, 70.3%. In conclusion, venous blood gas values can predict arterial blood gas values of pH, pCO2 and HCO3ecf, Be(ecf) and ctCO2- for healthy calves but only pH values in calves with acute respiratory problems (r2 value>80%).     

The effect of arterial blood sampling sites on blood gases and acid-base balance parameters in calves.

In 21 healthy calves, 1-6 months old, the interrelationship and comparability of acid-base balance variables (pH, HCO3-, BE) and blood gases (pCO2, pO2, and sat-O2) were evaluated in arterial blood collected from a larger, centrally localised (the a. axillaris) and a smaller peripheral artery (the a. auricularis caudalis). Sampling was done by direct puncture of the vessels without local anaesthesia. Except for blood pH, significant differences were observed in the average values of pCO2, pO2, HCO3-, sat-O2 (P < 0.001), and BE (P < 0.05). Analyses of blood from the a. axillaris showed higher pH, pO2, and sat-O2 values, and lower pCO2, HCO3-, and BE values compared with that from the a. auricularis caudalis. Despite statistically significant differences between some variables, in all indices high and significant correlation relationships were recorded (R = 0.928-0.961; P < 0.001). Therefore, from the biological and clinical point of view, these differences are unimportant and the presented method of peripheral arterial blood sampling can be considered suitable for evaluating blood gases and acid-base status.     

The accuracy of the i-STAT portable analyser for measuring blood gases and pH in whole-blood samples from dogs

To assess the suitability of the i-STAT portable analyser for use by non-laboratory personnel, we measured blood gases and pH in venous blood samples from 100 dogs. Deming's regression and bias plots were used to compare i-STAT results with those obtained by laboratory professionals using two different autocalibrated benchtop analysers. Overall accuracy of the portable analyser proved excellent for pH, pO(2), and pCO(2) (r=0.978, 0.968 and 0.997, respectively), with Deming's regression slopes close to 1.00 (0.96, 0.97 and 1.08 for pH, pO(2), and pCO(2), respectively) and intercepts close to zero (0.28, 0.47 kPa and 0.46 kPa for pH, pO(2), and pCO(2), respectively). The accuracy of the i-STAT was also satisfactory for calculated parameters: bicarbonates, total CO(2), base excess and oxygen saturation. Our findings show this portable analyser to be a valid substitute for expensive benchtop analysers in situations requiring mobility, or when small numbers of tests are to be performed by users not specialized in laboratory techniques.     

The effect of propofol on acid-base balance and ionic composition of venous and arterial blood in goats

The aim of the present study was to determine the effect of propofol on acid-base balance and ionic composition of arterial and venous blood in clinically healthy goats. The experiment was performed on ten adult goats. Propofol was administered intravenously at bolus dose of 6 mg/kg bw. The heart and breath rate, acid-base balance (pH, pCO2, pO2, HCO3-, BE, O2SAT, ctCO2) and ionic composition (Na+, K+, Cl-) of arterial and venous blood were measured before injection and 3, 6 and 15 min. after. The propofol infusion induced increase of heart rate, decrease of breath rate and compensated respiratory acidosis in venous and arterial blood. It was found that changes of acid-base balance parameters in arterial blood arose faster than in venous blood. The levels of sodium and chloride ions in both types of blood were similar, whereas the level of potassium ions was higher in venous blood during entire experiment.     

Acidosis and clinical condition in asphyctic calves

In depressed calves (modified APGAR score 4-6) there is at birth an evident combined respiratory-metabolic acidosis (pH = 7.082 +/- 0.175; pCO2 = 73.3 +/- 26.8 mm Hg; BE = -10.6 +/- 7.2 mmol/l). The metabolic adaptation is completed after 6 hours, the respiratory acidosis is present up to 24 hours after delivery. In comparison to normal calves there are significant deviations in pH-values, base excess standard bicarbonate and actual bicarbonate during the whole investigation time. The carbon dioxide tensions of the depressed calves are at birth similar to those of normal calves, but in the following hours they are significantly higher. A definite relationship can be demonstrated between the 1 minute APGAR score and pH-value, base excess, standard bicarbonate and actual bicarbonate. Oxygen tension, oxygen saturation and carbon dioxide do not correlate with the clinical condition.     

Comparison between pre‐ and postnatal acid‐base status of calves and their perinatal mortality

Summary

The acid‐base status of 58 calves (all in normal anterior presentation) was determined from venous blood samples before the onset of traction and immediately after vaginal delivery.

Calves were assigned to one of three groups according to their blood pH value: group 1 ‐ normal, pH >7.2; group 2 ‐ acidotic, pH 7.2 to 7.0; group 3 ‐ severely acidotic, pH < 7.0. Before the onset of traction (i.e. during the 30 minutes following the appearance and rupture of the membranes), 43 calves (74.1%) had normal acid‐base values, 14 (24.1%) had slight acidosis, and only 1 (1.7%) had severe acidosis. At birth the three groups of calves showed the following distribution: 23 (39.7%) were normal, 29 (50%) had slight acidosis, and 6 (10.3%) had severe acidosis.

Seven calves (12. 1%) died during birth or within 48 hours after birth; 2 were normal shortly before birth, 4 were acidotic shortly before birth, and 1 was severely acidotic even before the onset of traction. Traction was significantly longer for cows that delivered severely acidotic calves compared to cows in the other two groups.     

Physiologic measures of nonhuman primates during physical restraint and chemical immobilization.

The arterial acid-base balance and other selected physiologic measures of physically restrained and chemically immobilized nonhuman primates from the families Callithricidae, Cebidae, Cercopithecidae, and Pongidae were compared. The physically restrained primates had significantly lower pH, pCO2, and base excess values, but they had significantly higher pO2 values, rectal temperatures, and pulse and respiration rates. Of 56 physically restrained primates, 30 (54%) experienced severe metabolic acidosis, with pH values less than 7.2; 15 (27% of total) had pH values less than 7.1. Two types of behavior were observed during the physical restraint of golden marmosets. Some of the marmosets were excited during restraint, with a great deal of struggling and vocalizing. The other marmosets were quiet and calm, with minimal struggling. The excited group had significantly lower pH, pCO2, and base excess values, but significantly higher pO2 values, rectal temperatures, and pulse and respiration rates. Primates immobilized with ketamine or tiletaminezolazepam had a near normal acid-base balance and were handled more easily than the physically restrained animals.     

Acid-base balance parameters and a value of anion gap of arterial and venous blood in Małopolski horses

The comparative study of the acid-base balance (ABB) parameters has been performed on 20 clinically healthy mature Ma?opolski horses. An arterial blood sample from the facial artery and a sample of venous blood from the external cervical vein were colected from each animal. In the samples tested, the blood pH, pCO2, tCO2, HCO3-, concentration of Na+, K+, Cl-, and a value of the anion gap were determined. The difference among pCO2, tCO2, and HCO3- in both samples tested was statistically significant, whereas the pH of the arterial blood and the pH of the venous blood did not differ significantly. The anion gap in both types of blood did not differ significantly. Conclusions: 1) ABB parameters such as pCO2, HCO3-, and tCO2 determined in the arterial and venous blood of the Ma?opolski horses differ from each other significantly. 2) In spite of the lack of the differences between pH of the arterial and venous blood, the ABB parameters in horses should be determined in the arterial blood, because the comparative study performed proves that the analysis of the ABB parameters determined for the venous blood of a healthy horse may lead to a wrong diagnosis of the compensated respiratory acidosis. 3) The mean value of anion gap in horses aged 8-12 years amounts to 20.9 mmol/l for the arterial blood and 19.93 for the venous blood; the difference between the two values is not statistically significant.     

Agreement between arterial and central venous blood pH and its contributing variables in anaesthetized dogs with respiratory acidosis

ObjectiveTo determine the accuracy of variables that influence blood pH, obtained from central venous (jugular vein) blood samples compared with arterial (dorsal pedal artery) samples in anaesthetized dogs with respiratory acidosis.Study designProspective, comparative, observational study.AnimalsA group of 15 adult male dogs of various breeds weighing 17 (11-42) kg [median (range)].MethodsDogs were premedicated with buprenorphine (0.03 mg kg^–1) and medetomidine (0.01 mg kg^–1) administered intramuscularly by separate injections, anaesthetized with propofol intravenously to effect and maintained with isoflurane in 50% air-oxygen. Arterial and central venous catheters were placed. After 15 minutes of spontaneous breathing, arterial and central venous blood samples were obtained and analysed within 5 minutes, using a bench-top gas analyser. Differences between arterial and central venous pH and measured variables were assessed using Wilcoxon rank sum test and effect size (r: matched-pairs rank-biserial correlation) was calculated for each comparison. The agreement (bias and limits of agreement: LoAs) between arterial and central venous pH and measured variables were assessed using Bland-Altman; p < 0.05. Data are reported as median and 95% confidence interval.ResultsArterial blood pH was 7.23 (7.19-7.25), and it was significantly greater than central venous samples 7.21 (7.18-7.22; r = 0.41). Agreement between arterial and venous pH was acceptable with a bias of 0.01 (0.002-0.02) and narrow LoAs. PCO₂ [arterial 54 (53-58) mmHg, 7.2 (7.1-7.7) kPa; venous 57 (54-62) mmHg, 7.6 (7.2-8.3) kPa], bicarbonate ion concentration and base excess did not differ between samples; however, agreement between arterial and venous PCO₂ was not acceptable with a bias of –2 (–5 to 0) mmHg and wide LoAs.Conclusions and clinical relevanceBlood pH measured from central venous (jugular vein) blood is an acceptable clinical alternative to arterial blood (dorsal pedal artery) in normovolaemic anaesthetized dogs with respiratory acidosis.     

Optimal timing of elective caesarean section in Belgian White and Blue breed of cattle: the calf's point of view

The purpose of this study was to evaluate whether the timing of elective caesarean section (ECS) during parturition affects pulmonary and metabolic adaptation to extra-uterine life in healthy Belgian White and Blue (BWB) calves delivered at term. Vaginal palpation was performed and deliveries divided into six categories of timing for ECS: cervix closed (TECS 1); passive and active cervical dilatation (TECS 2 and TECS 3); full cervical dilatation (TECS 4); spontaneous rupture of allantoic (TECS 5) and amniotic (TECS 6) membranes.One hundred and eighteen BWB calves were examined at birth, 5, 15, 30, 45 and 60 min and 2, 3, 6, 12 and 24 h after birth using the following measurements: physical examination (time between birth and sternal recumbency [T-SR]); heart rate (mHR); arterial blood gas analyses (arterial partial pressure in oxygen [PaO(2)], in carbon dioxide [PaCO(2)], arterial haemoglobin oxygen saturation [SaO(2)], alveolo-arterial difference in oxygen [AaDO(2)]); pulmonary function tests using the oesophageal balloon catheter technique (respiratory rate [RR], total pulmonary resistance [R(L)], dynamic lung compliance [C(Ldyn)], tidal volume [V(T)] and minute volume [V(E)]); arterial and venous blood acid-base balance analyses (arterial and venous pH [pHa and pHv], bicarbonate concentration [HCO(3)a and HCO(3)v], base excess [BEa and BEv]); rectal temperature (RT); jugular venous blood sampling for determination of metabolic variables (blood glucose [G], plasma lactate [L], serum cortisol [C], plasma noradrenaline [NA] and adrenaline [A] concentrations); haematological variables (red blood cell count [RBC], total haemoglobin concentration [Hb], Packed Cell Volume [PCV]) and passive immune transfer variables (total serum protein [TP] and beta(2)gammaglobulin [beta(2)gamma] concentrations).TECS significantly (P or =4 calves, TECS< or =3 calves showed lower PaO(2), SaO(2), V(T), C(Ldyn), RT, G, NA, A, RBC, Hb and TP and higher AaDO(2), RR, V(E). TECS differences progressively decreased and disappeared between 6 and 12 h after birth in TECS 2 and 3 calves but remained up to 24 h in TECS 1 calves. Improved postnatal respiratory and metabolic adaptation in TECS> or =4 calves were mainly related to differences in exposure to labour and subsequent hormonal surge: catecholamines, particularly A, enabled more effective removal of lung liquid and/or release of surfactant which contribute to better gas exchanges and induced greater energy mobilization to maintain adequate body temperature.It was concluded waiting for full cervical dilatation before performing CS should be encouraged because it promotes postnatal respiratory and metabolic adaptation in full-term BWB calves.     

Comparison between pre- and postnatal acid-base status of calves and their perinatal mortality

The acid-base status of 58 calves (all in normal anterior presentation) was determined from venous blood samples before the onset of traction and immediately after vaginal delivery. Calves were assigned to one of three groups according to their blood pH value: group 1 - normal, pH greater than 7.2; group 2 - acidotic, pH 7.2 to 7.0; group 3 - severely acidotic, pH less than 7.0. Before the onset of traction (i.e. during the 30 minutes following the appearance and rupture of the membranes), 43 calves (74.1%) had normal acid-base values, 14 (24.1%) had slight acidosis, and only 1 (1.7%) had severe acidosis. At birth the three groups of calves showed the following distribution: 23 (39.7%) were normal, 29 (50%) had slight acidosis, and 6 (10.3%) had severe acidosis. Seven calves (12.1%) died during birth or within 48 hours after birth; 2 were normal shortly before birth, 4 were acidotic shortly before birth, and 1 was severely acidotic even before the onset of traction. Traction was significantly longer for cows that delivered severely acidotic calves compared to cows in the other two groups.     

Changes in fetal and maternal blood at the end of pregnancy and during parturition in the pig

Fetal and maternal blood gas tensions, pH, packed cell volume and glucose, fructose and lactic acid concentrations were monitored during the last two days of gestation, during parturition and and the first hour after birth. Blood samples were taken by means of indwelling catheters (implanted seven to 14 days before parturition) from 12 fetuses in seven sows. All fetuses were liveborn at a mean gestational age of 113.1 days. The significant finding was that all variables in fetal blood were stable during labour and, although mild hypercapnia was present during the last three hours, no significant changes in mean values were seen until those of samples taken within 15 minutes of birth. In some fetuses, no changes were seen until after birth, while in others pH and pO2 values declined during the last hour of fetal life. Immediately after birth a rapid increase in pO2 and decrease in pCO2 followed the onset of respiration. Blood pH fell during the first 30 minutes after birth and this fall was accompanied by increasing blood lactic acid concentrations. Blood glucose concentrations rose rapidly in the first 15 minutes after birth and were maintained during the first hour despite separation of the piglets from the sow. There was a transient, but significant, increase in packed cell volume during the period from 15 minutes before to 15 minutes after birth. Maternal values for all variables measured remained virtually unchanged during delivery.     

Reactions of dairy calves exposed to transport stress at 60 days of age. Effects of various rearing conditions in the developmental quality of calves on physiological variables and their changes

Dairy calves reared in groups of constant (Gk, N = 16, m 8, w 8) and changing composition (Gw, N = 16, m 8, w 8) and single box reared calves (E, N = 15, m 8, w 7) were exposed to transport stress lasting around 60 minutes at 60 days of age. Long term measurements of heart rate (HF) were combined with blood sampling (V. jugularis) before and immediately after transport and at the following day as well. Mean differences of HF, Hb, Hk, lactate and blood urea between groups were found at all sampling points. After transport mean values of HF, MetHb, pO2, O2SAT and O2CONT were increased in all calves and such of HHb were decreased. Measures of acid-base balance and lactate changed differently in calves of the three rearing groups concerning direction and degree. Changing of the variables after transport comparing the starting values was different between rearing groups in 16 out of 25 possible cases. Changing of variables immediately after transport showed strong negative correlations with starting values in case of pH, HCO3, base excess, COHb, total protein, albumin, lactate, glucose and Ca in all groups, in all other cases not in all groups. Strong correlations between sampling points of Hb, Hk, MCHC, O2CONT, O2CAP, creatinine, blood urea and of the minerals indicate a high individual specificity of these measures. Results proof variation components of physiological variables in calves caused by husbandry conditions and their effects on reactions of animals in case of transport stress.     

Effects of hypertonic sodium bicarbonate solution on electrolyte concentrations and enzyme activities in newborn calves with respiratory and metabolic acidosis

OBJECTIVE: To determine concentrations of electrolytes, total bilirubin, urea, creatinine, and hemoglobin; activities of some enzymes; and Hct and number of leukocytes and erythrocytes of newborn calves in relation to the degree of acidosis and treatment with a hypertonic sodium bicarbonate (NaHCO(3)) solution. ANIMALS: 20 acidotic newborn calves with a blood pH < 7.2 and 22 newborn control calves with a blood pH > or = 7.2. PROCEDURES: Approximately 10 minutes after birth, acidotic calves were treated by IV administration of 5% NaHCO(3) solution. The amount of hypertonic solution infused was dependent on the severity of the acidosis. RESULTS: Treatment resulted in a significant increase in the mean +/- SEM base excess from -8.4 +/- 1.2 mmol/L immediately after birth to 0.3 +/- 1.1 mmol/L 120 minutes later. During the same period, sodium concentration significantly increased from 145.3 +/- 0.8 mmol/L to 147.8 +/- 0.7 mmol/L. Mean chloride concentration before NaHCO(3) administration was significantly lower in the acidotic calves (99.6 +/- 1.1 mmol/L) than in the control calves (104.1 +/- 0.9 mmol/L). Calcium concentration in acidotic calves decreased significantly from before to after treatment. Concentrations of potassium, magnesium, and inorganic phosphorus were not affected by treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of hypertonic NaHCO(3) solution to acidotic neonatal calves did not have any adverse effects on plasma concentrations of several commonly measured electrolytes or enzyme activities. The treatment volume used was smaller, compared with that for an isotonic solution, which makes it more practical for use in field settings.     

Effect of high arterial carbon dioxide tension on efficiency of immunoglobulin G absorption in calves.

OBJECTIVES: To determine whether high PaCO2 reduced apparent efficiency of IgG absorption (AEA) in calves and whether assisted ventilation of calves with high PaCO2 increased AEA. ANIMALS: 48 Holstein calves. PROCEDURES: Arterial and venous blood samples were collected 1, 13, and 25 hours after birth; an additional venous sample was collected at 37 hours after birth. Arterial samples were analyzed for PaCO2, PaO2, pH, and bicarbonate and base excess concentrations; venous samples were analyzed for plasma IgG concentrations. On the basis of 1-hour PaCO2, calves were assigned to nonrespiratory acidosis (PaCO2 < 50 mm Hg; n = 19) or respiratory acidosis (PaCO2 > or = 50 mm Hg; 29) groups. Calves in the respiratory acidosis group were assigned randomly to receive no further treatment (n = 17) or to be given 5 minutes of assisted ventilation (12). All calves received between 1.8 and 2 L of colostrum 2, 14, 26, and 38 hours after birth. Plasma volume and AEA were determined 25 hours after birth. RESULTS: 1-hour PaCO2 had no effect on AEA or on plasma IgG concentrations determined 13, 25, or 37 hours after birth. Artificial ventilation had no effect on plasma IgG concentration or AEA. CONCLUSIONS AND CLINICAL RELEVANCE: Lack of effect of 1-hour PaCO2 on AEA and IgG concentration indicated that calves compensated for moderate acid-base imbalances associated with birth. Calves born with high PaCO2 achieved adequate plasma IgG concentrations if fed an adequate amount of high-quality colostrum early in life. The effect of artificial ventilation on PaCO2 was temporary and did not increase AEA.     

Metabolic profile of newborn calves and levels of immunoglobulins in the first days of life

After examination of the clinical state of 128 new-born calves, blood was collected from their vena jugularis for the determination of blood actual pH value, concentration of lactic acid, pCO2, base excess, buffer base and standard acid bicarbonate. The course and difficulty of parturition exerted a significant influence on the vitality of the calves and on the studied parameters of acid-base state. In the normally born calves, compared with those after dystocia, the following values were obtained: pH 7.20 +/- 0.03 : 7.11 +/- 0.07, pCO2 = 8.4 +/- 0.9 : 10.0 +/- 1.1 kPa, base excess -2.30 +/- 2.10 : 5.80 +/- 4.60 mmol/l, buffer base 43.0 +/- 2.4 : 39.5 +/- 6.5 mmol/l, standard acid bicarbonate 22.3 +/- 1.8 : 19.6 +/- 4.1 mmol/l and lactic acid concentration 5.6 +/- 2.0 : 10.7 +/- 5.1 mmol/l. The differences were statistically significant (P less than 0.05) and statistically highly significant (P less than 0.01). The continual study of the blood actual pH value and lactic acid concentration in the calves in the first 24 hours of life showed that with the same trend of changes in calves after dystocia the initial values were less favourable and that their normalization lasted longer. Attention is drawn to the importance of dystocia for the rise of respiratory metabolic acidosis and its effect on the vitality of newborn calves, and/or on their survival. The discussion deals with the importance of immunoglobulin levels in calves in the first days after birth for their further development. The determination of antibody content in colostral serum from the first milking in 33 and 29 cows on two farms showed great drawbacks in quality. A satisfactory level of IgG was found only in 36.36% and 58.62% of the cows, and a satisfactory level of IgM only in 12.12% and 24.13% of the studied cows. The determination of immunoglobulin content in their calves two to three days from birth (33 + 33 animals) showed normoglobulinemia only in 24.24% and 15.15% of cases. In 33 and 29 cows on two farms the colostrum serum from the first milking had an average content of immunoglobulins of class G amounting to 27.99 +/- 20.25 mg/ml and 36.95 +/- 21.62 mg/ml, and class M amounting to 3.64 +/- 1.25 and 2.04 +/- 1.42 mg/ml. Three days from birth, their calves had an IgG content of 4.25 +/- 2.57 mg/ml and 3.99 +/- 1.86 mg/ml and an IgM content of 0.30 +/- 0.20 and 6.38 +/- 0.25 mg/ml.     

Hyperthermia in the rabbit. II. Studies on influencing respiration with exogenic hyperthermia]

Rectal temperature, respiratory rate, arterial and venous pH and arterial and venous pCO2 were recorded at intervals of 15-30 minutes in female broiler rabbits exposed an environmental temperature of 35 degrees C, until they died. Respiratory rate and blood pH rose, and pCO2 fell, until a rectal temperature of 42 degrees C was reached. Upon further increase in rectal temperature the respiratory rate and pH began to fall, while pCO2 began to rise. The rabbits died when rectal temperature reached 43 degrees C. Features of respiratory function peculiar to the rabbit were discussed.     

Influence of the wing-of-the-nostrils correction procedure on the change of the acid-base balance parameters and oxygen concentration in the arterial blood in French bulldogs

Brachycephalic syndrome develops as a result of a specific build of splanchnocranium. In dogs of brachycephalic breeds, an impairment of correct gas exchange occurs. 5 French bulldogs at the age of 11-14 months, which suffered from continuous mixed-type dispnoea and lowered effort tolerance, were examined. Apart from the above-mentioned symptoms, the occurrence of strong external nostril stenosis was noted in the clinical examination. The symptoms observed together with the nostril stenosis indicated a possibility of an occurrence of the brachycephalic syndrome. 1 ml of full blood was drawn from the femoral artery. Acid-base balance parameters were determined in the arterial blood: pH, pCO2, HCO3-, and pO2. The wing-of-the-nostrils correction procedure were carried out in general anaesthesia. In premedication, the patients received medetomidine and after 15 minutes, fentanyl together with atropine. The induction of propofol was carried out. After four weeks from the procedure, blood was collected and the acid-base balance and pO2 parameters were again determined. The obtained values of the acid-base balance and pO2 parameters showed a noticeable influence of the wing-of-the-nostrils correction procedure on the values of the parameters determined. The results of the blood gasometry obtained prior to the procedure clearly indicate the occurrence of respiratory acidosis. The correction of wings of the nostrils significantly influenced saturation of the arterial blood with oxygen and the symptoms of dispnoea observed by the owners and episodes of apnoea and the loss of consciousness entirely subsided.     

Further studies on the clinical features and clinicopathological findings of a syndrome of metabolic acidosis with minimal dehydration in neonatal calves.

A syndrome of metabolic acidosis of unknown etiology was diagnosed in twelve beef calves 7 to 31 days old. Principal clinical signs were unconsciousness or depression concomitant with weakness and ataxia. Other signs included weak or absent suckle and menace reflexes, succussable nontympanic fluid sounds in the anterior abdomen, and a slow, deep thoracic and abdominal pattern of respiration. The variation in clinical signs between calves was highly correlated (r = 0.87, P less than 0.001) with their acid-base (base deficit) status. Abnormal laboratory findings included reduced venous blood pH, pCO2 and bicarbonate ion concentration as well as hyperchloremia, elevated blood urea nitrogen, increased anion gap and neutrophilic leukocytosis with a left shift. Sodium bicarbonate solution administered intravenously effectively raised blood pH and improved demeanor, ambulation and appetite. All calves did well following a return to a normal acid-base status.