首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 27 毫秒
1.
Muscle potassium content and supplementation with potassium gluconate were evaluated in normokalemic cats with chronic renal failure (CRF). Affected cats received standard medical therapy for renal failure and either placebo (sodium gluconate! or potassium gluconate. At the beginning of the study and after 6 months of supplementation, glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were estimated using 3H-inulin and 14C-tetraethylammo-nium bromide (TEA) clearances. Muscle potassium content was determined in biopsy specimens using atomic absorption spectroscopy. Muscle biopsy samples obtained from cats with CRF before treatment had significantly lower muscle potassium content than did those from normal control cats. Over the 6-month period of supplementation, muscle potassium content increased both in cats with CRF that received potassium gluconate and in those that received placebo (sodium gluconate). Serum potassium concentration and fractional excretion of potassium remained relatively unchanged in both groups of cats throughout the treatment period. There were no significant differences in the percentage change in GFR and ERPF between treatment groups over the 6-month time period. Median values for pH, HCO3, and total CO2 at 6 months were higher than baseline in the potassium gluconate group but lower than baseline in the sodium gluconate group.  相似文献   

2.
Acetazolamide was administered at a dose rate of 10 mg/kg intravenously every 8 h to twelve dogs for a period of 7 days. Before administration of the acetazolamide and every second day during the period of administration, values of PaO2, PaCO2, pH, base excess, bicarbonate, systolic and diastolic arterial pressure, central venous pressure, packed cell volume, haemoglobin and total plasma protein were measured. Plasma concentrations of sodium, potassium, chloride, creatinine, urea, glucose, bilirubin, iron, calcium, phosphate and triglycerides were also determined. These values were also measured in a similar control group of dogs not given acetazolamide. Acetazolamide produced significant elevations in PaO2 and chloride values and significant decreases in PaCO2, pH, base excess, bicarbonate, potassium and calcium. There were no significant changes in any of the other parameters measured. The non-respiratory acidosis produced by acetazolamide makes it a useful model to enable the investigation of therapeutic regimes for treating acidosis of this type.  相似文献   

3.
Some physiological effects of the intravenous administration of five different commercial electrolyte solutions were studied in healthy conscious dogs. Measurements were taken before, during and up to 3 h after fluid administration. The measurements included temperature, heart rate, respiratory rate, systolic and diastolic arterial pressure, central venous pressure, pO2, pCO2, pH, packed cell volume, haemoglobin, total plasma protein, sodium, potassium, chloride, bicarbonate, base excess and creatinine. There were no significant changes in temperature, respiratory rate, systolic pressure, pO2 or pCO2. All dogs showed a similar rise in central venous pressure and a fall in packed cell volume, haemoglobin and total plasma protein in response to the fluid administration. Two saline solutions produced a metabolic acidosis, a fall in plasma potassium values and a rise in chloride. Administration of multi-electrolyte solutions resulted in the least disturbance in acid-base and electrolyte balance.  相似文献   

4.
This article considers ways in which simple changes in plasma composition (especially in the concentration of Na+, Ca++, Mg++ and glucose) can initiate most of the symptoms usually associated with neurological disorders. The more complex deterioration of plasma composition inflicted by renal or hepatic failure is also discussed and related to behavioural abnormalities. Although most of the relevant clinical observations have been in man, the extent to which experimental animals demonstrate similar effects suggests that the importance of these conditions in veterinary medicine may be underestimated. Even if they are less frequent, they deserve attention because, in principal, they are easily diagnosed and, in contrast to other neural disturbances, readily reversible.  相似文献   

5.
This report describes the use of 99mtechnetium pertechnetate (99mTcO4−) and 131[for imaging of a metastatic thyroid carcinoma in a dog. The 131] imaging showed metastatic lesions undetected by the 99mTcO4− imaging on 2 separate occasions. The possible mechanisms for the discrepancies between 131I and 99mTcO4− imaging of thyroid carcinomas are discussed. The use of 131I for the imaging of functional thyroid carcinomas in the dog is recommended.  相似文献   

6.
Contents: In this review, the role of eicosanoids in regulation of parturition and the postpartum period was described with special emphasis on the bovine species. The metabolism of arachidonic acid and the production of eicosanoids during the peripartum period was discussed. Prostaglandin E2 and F2α (PGE2, PGF2α) play an important role in mechanisms controlling parturition. They are involved in luteolysis, uterine contractions and dilation of the cervix. Eicosanoids also seem to influence the loosening processes of the fetal membranes. However, in the literature, conflicting results were found. Many investigations suggested that retained placental membranes could be related to low PGF2α production and/ or an imbalance of arachidonic acid metabolism in the uterus. The possible role of the lipoxygenase pathway metabolite 15-hydroxy-eicosatetraenoic acid (15-HETE) in expulsion of the fetal membranes was also discussed. As far as the postpartum period is concerned, a relationship between postpartum PGF2α release and the involution of the uterus was found. Cows with undisturbed uterine involution had higher PGF2α production than cows with delayed involution. In contrast to the positive effect of PGF2α on uterine involution, PGE2 seems to delay the involution processes. Further experiments are necessary in order to study the function of eicosanoids in mechanisms regulating parturition, release of the fetal placental membranes and involution of the uterus.  相似文献   

7.
Signs of malignant hyperthermia, including progressive increases in PaCO2, skin temperature and heart rate, and elevated serum levels of potassium, inorganic phosphate, and creatine kinase, were identified in a halothane-anesthetized horse. Treatment was discontinuing halothane administration, applying ice and cold fluids, and hyperventilating with 100% oxygen. After an initial recovery, bilateral hindlimb myopathy and pigmenturia developed. The myopathy resolved after treatment with oral dantrolene, IV fluids, and hydrocortisone. Results of caffeine-halothane challenge, using semimembranosus muscle collected 2 weeks after the episode, were considered within normal limits for horses. The intraoperative abnormalities were evidently predictive of postanesthetic myopathy but the cause in this horse remained unclear.  相似文献   

8.
Thyroid scintigraphy using sodium 99mTechnetium pertechnetate (99TcO4-) was performed in normal and radiothyroidectomized cockatiels ( Nymphicus hollandicus ). 131I scintigraphy was performed in the course of ablating the thyroid glands. The thyroid glands in normal birds were clearly visualized, but were not individually resolvable. Thyroid glands were not visualized in thyroid-ablated birds. With 99mTcO4 scans, thyroid (or other region of interest)/body count density ratios were used for comparisons of normal and thyroid-ablated birds. Normal 99mTcO4- thyroid/body ratios (mean +/− SD) for the dorsal and lateral views were 1.83 +/− 0.31 and 1.70 +/− 0.34 respectively. Pertechnetate thyroid/body count density ratios decreased (to 0.93 -/−0.14 and 0.88 +/− 0.12 for dorsal and lateral views respectively) after thyroid ablation, while crop/body ratios increased. 99mTcO4- thyroid scintigraphy, therefore, was capable of detecting hypofunctional thyroid abnormalities in 131I radiothyroidectomized cockatiels.  相似文献   

9.
Eighty cats with chronic renal failure (CRF) were evaluated in a prospective study to investigate the prevalence and aetiopathogenesis of renal secondary hyperparathyroidism (RHPTH), using routine plasma biochemistry and assays of parathyroid hormone (PTH), blood ionised calcium and 1,25 dihydroxycholecalciferol (1,25[OH]2D3). Hyperparathyroidism was a frequent sequela of CRF, affecting 84 per cent of cats with CRF, the severity and prevalence of RHPTH increasing with the degree of renal dysfunction. Compared with an age-matched control population, plasma concentrations of phosphate and PTH were significantly higher and 1,25(OH)2D3 concentrations were significantly lower in the two groups of cats presenting with clinical signs of CRF. Significant ionised hypocalcaemia was present only in cats with end-stage renal failure. However, a number of cats were hyperparathyroid in the absence of abnormalities in the parameters of calcium homeostasis measured in this study. There was a significant correlation between plasma phosphate and PTH concentrations.  相似文献   

10.
CASE DESCRIPTION: A 6-year-old male castrated Shetland Sheepdog was evaluated because of severe hypokalemia and progressive paresis. CLINICAL FINDINGS: Physical examination revealed fever, tachypnea, mydriasis, hyperemic mucous membranes, severe forelimb paresis, and hind limb paraplegia. The dog had superficial and deep pain sensation in all 4 limbs. Forelimb spinal reflexes were considered normal, but hind limb reflexes were normal to slightly hyperreflexive. The panniculus reflex was considered to be normal, and cranial nerve reflexes were intact. A CBC revealed mild leukocytosis and erythrocytosis, and serum biochemical analysis revealed severe hypokalemia. Thoracic and abdominal imaging did not reveal relevant findings. Blood pressure and ECG findings were within reference limits. Questioning of the owner revealed possible exposure to albuterol via ingestion of medication intended for the owner's horse. Results of serum testing via immunoassay were suggestive of albuterol toxicosis. TREATMENT AND OUTCOME: Treatment included IV administration of an electrolyte solution and supplemental potassium chloride. The rate of potassium chloride supplementation was slowly decreased as serum potassium concentration increased. No other medical intervention was required, and the dog made a rapid and complete recovery. CLINICAL RELEVANCE: Ingestion of albuterol can lead to profound physical and serum biochemical abnormalities. Appropriate historical information should be obtained to identify possible sources and routes of exposure to intoxicants. Albuterol-induced hypokalemia can be successfully managed medically.  相似文献   

11.
Cell numbers of known species of nitrate- and nitrite-reducing bacteria, Selenomonas ruminantium, Veillonella parvula and Wollinella succinogenes , in the rumen of goats (25–30 kg) were estimated by competitive polymerase chain reaction (PCR). The number of S. ruminantium was the largest of the three species examined, and tended to be greater in goats fed a high-concentrate diet (5.6 × 107 cells/mL rumen fluid) than in goats fed a high-roughage diet (1.3 × 107 cells/mL). The number of V. parvula tended to be greater when goats were fed a high-roughage diet (6.7 × 103/mL) than when fed a high-concentrate diet (3.2 × 103/mL). The number of W. succinogenes was below the detectable level (< 1.0 × 102/mL) when a high-concentrate diet was fed, but was significantly increased by feeding a high-roughage diet (1.6 × 103/mL). Addition of potassium nitrate (6 g/day) to the high-concentrate diet tended to increase V. parvula , and significantly increased W. succinogenes , indicating that these two bacteria can be increased by feeding a diet containing nitrate.  相似文献   

12.
Thoracotomy in dogs often is associated with lower than expected arterial oxygen tensions (PaO2). Pulmonary collapse from opening the thoracic cavity is likely to be responsible for decreased PaO2 during thoracotomy. To examine whether positive end-expiratory pressure (PEEP) is beneficial to dogs undergoing thoracotomy, PaO2 and hemoglobin saturation (SaO2) were measured in dogs randomly assigned to receive 5 cm of H2O PEEP (n = 7) or no PEEP (n = 9). During surgery in both groups of dogs, PaO2 progressively decreased ( P < .001), but the decrease in PaO2 was significantly less in the PEEP group ( P = .027). In both groups, PaO2 did not decrease enough to have a substantial effect on SaO2. Furthermore, application of PEEP during thoracotomy did not prevent moderate hypoxemia after surgery and discontinuation of PEEP. Application of 5 cm of H2O PEEP seems to attenuate the decrease in PaO2 observed in dogs undergoing thoracotomy, but routine application of PEEP does not seem justified. ©  相似文献   

13.
A viable preparation from the external muscle coat of cattle rumen for in vitro studies of contractility is described. The threshold Ca2+ concentration for contractile response in glycerol treated ruminal muscle was found to be pH dependent. At physiological pH it is situated between 10-8 and 10-7 M. Strips with intact membranes were studied in the depolarized state. In this preparation contraction to acetylcholine or histamine requires Ca2+ in the medium. However, contractility persists for several minutes in Ca2+-free solution at rest but disappears rapidly during stimulation. Recovery in a Ca2+-containing medium is much faster than the decline of responsiveness in a Ca2+-free medium. Tetracaine and D600 seem to inhibit contraction by blocking release of Ca2+ from and uptake of Ca2+ into hypothetical Ca stores inside the cell. The results are interpreted by assuming cellular Ca stores and two Ca pumps, one extruding Ca2+ into the medium and one accumulating Ca in the stores. Acetylcholine and histamine act by increasing Ca2+ permeability of both the membranes of the stores and the plasma membrane. The stimulator-induced and possibly the resting Ca2+ permeability in the depolarized state is reduced by tetracaine and D600 at both sites. The pumps are assumed not to be affected by stimulators and the mentioned drugs.  相似文献   

14.
The pharmacodynamics and enantioselective pharmacokinetics of vedaprofen were studied in six ponies in a two period cross-over study, in which a mild acute inflammatory reaction was induced by carrageenan soaked sponges implanted subcutaneously in the neck. Vedaprofen, administered intravenously at a dosage of 1 mg/kg, produced significant and prolonged inhibition of ex vivo serum thromboxane B2 (TXB2) synthesis and short-lived inhibition of exudate prostaglandin E2 (PGE2) and TXB2 synthesis. Vedaprofen also partially inhibited oedematous swelling and leucocyte infiltration into exudate. Vedaprofen dis-played enantioselective pharmacokinetics, plasma concentrations of the R(–) enantiomer exceeding those of S(+) vedaprofen. The plasma concentration ratio, R:S, increased from 69: 31 at 5 min to 96: 4 at 3 h and plasma mean AUC values were 7524 and 1639 ng.h/mL, respectively. Volume of distribution was greater for S(+) vedaprofen, whilst elimination half-life (t½β) and mean residence time were greater for R(–) vedaprofen. The penetration of vedaprofen into inflammatory exudate was also enantioselective. For R(–) and S(+) veda-profen maximum concentration (Cmax) values were 2950 and 1534 ng/mL, respectively, and corresponding AUC values were 9755 and 4400 ng.h/mL. Vedaprofen was highly protein bound (greater than 99%) in both plasma and exudate. The significance of these data for the therapeutic use of vedaprofen is discussed.  相似文献   

15.

Objective

To describe the presentation of rebound hyperkalemia as a delayed side effect of albuterol toxicity in a dog.

Case Summary

A 3-year-old female neutered mixed-breed dog was presented for albuterol toxicosis that led to a severe hypokalemia, hyperlactatemia, and hyperglycemia. The dog also experienced sinus tachycardia and generalized weakness. Treatment was instituted with intravenous fluid therapy and potassium supplementation, and the dog was monitored with a continuous electrocardiogram. Resolution of hypokalemia was documented 12 hours after initial presentation, at which time fluid therapy and potassium supplementation were discontinued. There were no further periods of sinus tachycardia, but instead the dog developed ventricular ectopy with rapid couplets (instantaneous rates of 300/min). An echocardiogram revealed normal cardiac size and function. Twenty-four hours after presentation, the patient developed severe hyperkalemia, despite discontinuation of fluids and potassium supplementation for 12 hours. Serial venous and urinary electrolytes were performed for determination of the fractional excretion of electrolytes. These data confirmed rebound hyperkalemia (7.0 mmol/L), consistent with a markedly increased fractional excretion of potassium, and secondary to the release of potassium from inside the cells. Fluid therapy with dextrose supplementation was provided until 36 hours postpresentation. The hyperkalemia resolved, and the dog was discharged after 44 hours of hospitalization.

New or Unique Information Provided

This case documents rebound hyperkalemia following treatment of albuterol toxicosis in a dog. This case highlights the importance of understanding the distribution of total body potassium when treating serum hypokalemia. Transcellular shifts of potassium, as in the case of albuterol toxicosis, can lead to rebound hyperkalemia even after discontinuation of potassium supplementation. This case further explores the utility of fractional excretion of electrolytes in elucidating the etiology and management of electrolyte disturbances.  相似文献   

16.
The effect of xylazine on the isolated sheep trachea and its possible interactions with the α2-adrenergic antagonist, atipamezole, and the anticholinergic agent, atropine, was studied. The mechanical responses of the tracheal preparations were recorded after exposing each one to cumulatively increasing concentrations of xylazine alone or in the presence of atipamezole or atropine.
Xylazine exerted a concentration-dependent contractile effect, with a threshold concentration of 10--7M while the maximum activity was produced at a concentration of 10--5M (EC50= 2.3 × 10--7). This xylazine-induced contractile effect was inhibited by atipamezole, but not significantly modified by atropine. Thus, it is concluded that α2-adrenoceptors exist in the sheep trachea and it is suggested that α2-adrenoceptor agonists may act on airways in sheep directly through stimulation of peripheral α2-adrenergic receptors and indirectly via central α2-adrenergic receptor activation of parasympathetic tone.  相似文献   

17.
Cytosolic Ca2+ is known to be an important factor in intracellular signaling pathways that regulate several cellular functions. The present study was designed to measure the intracellular concentrations of Ca2+ ([Ca2+]i) in T cell mitogen-stimulated chicken lymphocytes, and to compare the results with those in rat lymphocytes. [Ca2+]i was increased in the thymocytes, splenocytes and bursacytes of chickens, and in the thymocytes and splenocytes of rats following exposure to the mitogens phytohaemagglutinin (PHA) and concanavalin A (ConA). Increases were greatest in the thymocytes followed by the splenocytes and bursacytes. The PHA-induced changes in the thymocytes and splenocytes were similar in chickens and rats, but the ConA-induced increases were significantly lower in the chickens than rats. Pretreatment with EGTA before the application of PHA and ConA completely suppressed the rise in [Ca2+]i in all the chicken lymphocytes, indicating that the increases that occurred in PHA- and ConA-treated chicken lymphocytes could be entirely attributed to the influx of extracellular Ca2+. On the other hand, the PHA- and ConA-induced increase in [Ca2+]i in rat lymphocytes was not completely suppressed by EGTA, indicating the recruitment of Ca2+ from the intracellular Ca2+ pool. The results suggest species differences in the Ca2+-based responses to T cell mitogens between chicken lymphocytes and rat lymphocytes.  相似文献   

18.
Improvements in human patient monitoring despite their development in animals, do not always find their way into veterinary clinical use due to financial constraints. Gastrointestinal intraluminal CO2 partial pressure (Gip1CO2) monitoring, however, is not only proving very beneficial in human trauma and critical patient care but is also very likely to become relatively inexpensive. By providing information on the perfusion adequacy of a high risk, critically important tissue, the GI mucosa, GI P1CO2 monitoring offers an easily accesible indicator of the efficacy and adequacy of resuscitative interventions. The potential for decreasing morbidity and mortality is enormous. Therefore, the practicing veterinarian should become familiar with GI P1CO2 monitoring theory and technology so he or she can be better prepared to incorporate it into practice when in becomes available.  相似文献   

19.
The purposes of this study were 2-fold: (1) to determine the prevalence of splintered QRS complexes (Rr', RR', rR', rr') and other electrocardiographic abnormalities in dogs and cats with congenital right atrioventricular valve malformation (RAVM) and (2) to determine if the Labrador Retriever was at greater risk for RAVM and splintered QRS complexes. EKGs from 39 dogs and 6 cats with echocardiographically diagnosed RAVM were studied retrospectively. Splintered QRS complexes were commonly found in affected Labrador Retrievers (9 of 19, 47%), non-Labrador Retrievers (12 of 20, 60%), and cats (4 of 6, 67%). Right ventricular enlargement was most commonly detected by precordial leads (CV6LL[V2], CV6LU[V4]) in the dogs and by the standard limb leads in the cats. Arrhythmias were uncommon. The Labrador Retriever was significantly overrepresented (P < .001) in the RAVM group when compared to the general hospital population (50% versus 8%). Males were also significantly overrepresented ( P < .01). It was concluded that splintered QRS complexes are a distinctive and common electrocardiographic finding in dogs and cats with RAVM. Moreover, this congenital cardiac defect is most common in the Labrador Retriever, although this breed does not have proportionately more or less splintering of the QRS complexes than other breeds.  相似文献   

20.
The accuracy and precision of an end-tidal infrared CO2 monitor and customized capnography tubing system designed to measure gastrointestinal intraluminal CO2 partial pressure (PiCO2) were tested in vitro. Samples were taken from the customized capnography tubing placed in either 5% or 10% CO2 gas at discrete intervals ranging from one minute to twelve minutes. For a given time interval, the tubing PCO2 measurement was a constant fraction of the actual PCO2 (all standard errors < 0.02). For increasing time intervals, the ratio of the tubing PCO2 to actual PCO2 increased logarithmically. In the 5% and 10% CO2, the regression coefficients were 0.89 and 0.85 for 8 French tubing and 0.99 and 0.91 for 6 French tubing. Beacuase of its accuracy and precision, this system may provide automated gastrointestinal CO2 partial pressure monitoring at short intervals (e.g. 5 minutes), facilitating testing of the role of gastrointestinal PiCO2 information in treatment algorithms. (Vet Emerg & Crit Care, 1998; 8: 109–116)  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号