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This study investigated the applicability of two human radio-immunoassays (RIA) to detect epinephrine (EPI), norepinephrine (NE), and their O-methylated metabolites metanephrine (MN) and normetanephrine (NMN) in canine plasma. The analysis yielded a positive correlation between metabolites and their respective parent compounds: EPI and MN (r=0.63), NE and NMN (r=0.47), as well as between parent compounds, EPI and NE (r=0.48), and between metabolites MN and NMN (r=0.71). Moreover, EPI (r=0.99) and NE (r=0.77) concentrations determined by RIA did correlate positively with high pressure liquid chromatography (HPLC). However, there was limited agreement between both methods. It was concluded that complete validation tests for accuracy, precision and agreement are needed before this RIA can be applied to quantify catecholamines, metanephrine, and normetanephrine in canine plasma. The assay may prove to be a potential alternative to HPLC or tandem mass spectrometry in the work-up of pheochromocytoma and the detection of overall sympathetic activity in dogs.

Cardiopulmonary resuscitation of a child is a rare, emotionally affective, challenging and potentially frightful event. Current guidelines have been largely simplified to facilitate teaching and retention, to encourage bystander resuscitation, and to improve the quality of resuscitation by healthcare professionals. This article is a practical approach to the current european guidelines (ERC), including basic and advanced life support algorithms, as well as recommendations on the post-resuscitation periode and parental presence.

Regional anesthesia has many advantages as intraoperative and more important as postoperative analgesia in pediatric anesthesia. There are special requirements for a sufficient acute pain management in preterms, newborns and small infants. This review focuses these special features regarding to local anesthetics and supplements, caudal and spinal anesthesia, and peripheral blockades.

Acute hypoxic pulmonary vasoconstriction can be inhibited by high doses of the carbonic anhydrase inhibitor acetazolamide. This study aimed to determine whether acetazolamide is effective at dosing relevant to human use at high altitude and to investigate whether its efficacy against hypoxic pulmonary vasoconstriction is dependent on carbonic anhydrase inhibition by testing other potent heterocyclic sulfonamide carbonic anhydrase inhibitors. Six conscious dogs were studied in five protocols: 1) controls, 2) low-dose intravenous acetazolamide (2 mg·kg−1·h−1), 3) oral acetazolamide (5 mg/kg), 4) benzolamide, a membrane-impermeant inhibitor, and 5) ethoxzolamide, a membrane-permeant inhibitor. In all protocols, unanesthetized dogs breathed spontaneously during the first hour (normoxia) and then breathed 9–10% O2 for the next 2 h. Arterial oxygen tension ranged between 35 and 39 mmHg during hypoxia in all protocols. In controls, mean pulmonary artery pressure increased by 8 mmHg and pulmonary vascular resistance by 200 dyn·s·cm−5 ( P −5 during hypoxia ( P < 0.05). Low-dose acetazolamide is effective against acute hypoxic pulmonary vasoconstriction in vivo. The lack of effect with two other potent carbonic anhydrase inhibitors suggests that carbonic anhydrase is not involved in the mediation of hypoxic pulmonary vasoconstriction and that acetazolamide acts on a different receptor or channel.

The objective of this study was to investigate whether circulatory and hormonal changes during xenon plus remifentanil or isoflurane plus remifentanil anesthesia are altered by endothelin-A (ET(A)) receptor blockade. Eight beagle dogs were studied in four protocols (n = 7 each). After a 30-min awake period, anesthesia was induced with 8 mg/kg propofol, administered intravenously (iv), and maintained with either 0.8% +/- 0.01% (vol/vol) isoflurane plus 0.5 microg/kg/min remifentanil (Protocol 1) or 63% +/- 1% (vol/vol) xenon plus 0.5 microg/kg/min remifentanil (Protocol 2) for 1 hr. Protocols 3 and 4 were preceded by ET(A) blockade with ABT-627 (Atrasentan; iv bolus of 1 mg/kg, then 100 microg/kg/h continuously). Irrespective of Atrasentan administration, the mean arterial blood pressure (MAP) ranged between 92 and 96 mm Hg in the awake state and fell to 67 +/- 3 mm Hg in controls (mean +/- SEM) and to 64 +/- 2 mm Hg in the Atrasentan group during isoflurane plus remifentanil anesthesia, whereas MAP remained constant during xenon plus remifentanil anesthesia. A decrease in heart rate was observed during either kind of anesthesia, but bradycardia was most prominent during xenon plus remifentanil anesthesia. In the control groups, and in the Atrasentan-treated dogs, a decrease in cardiac output and an increase in systemic vascular resistance were more prominent during xenon plus remifentanil than during isoflurane plus remifentanil anesthesia. Hormonal alterations during anesthesia remained unaffected by ET(A) receptor blockade. Angiotensin II and vasopressin increased in all protocols, and adrenaline and noradrenaline concentrations rose only during xenon plus remifentanil anesthesia. We conclude that the hemodynamic and hormonal adaptation after xenon plus remifentanil and isoflurane plus remifentanil anesthesia does not depend on the endothelin system, because it is unaffected by ET(A) receptor inhibition. Therefore, the use of Atrasentan does not impair cardiovascular stability during xenon- or isoflurane-based anesthesia in our dog model. However, the way anesthesia is performed is of crucial importance for hemodynamic and hormonal reactions observed during research in animals because the release of vasopressin and catecholamines may be intensified by xenon plus remifentanil anesthesia.

Percutaneous central venous cannulation of small infants is a challenging procedure. The use of ultrasound guidance has been shown to increase the success rate generally in children and to decrease the incidence of associated complications. To demonstrate that this technique is also suitable in very small infants we describe the case of a preterm neonate of 850 g body weight (BW), in which percutaneous central venous cannulation was performed successfully using ultrasound imaging for guidance.

Acute hypoxia increases pulmonary arterial pressure and vascular resistance. Previous studies in isolated smooth muscle and perfused lungs have shown that carbonic anhydrase (CA) inhibition reduces the speed and magnitude of hypoxic pulmonary vasoconstriction (HPV). We studied whether CA inhibition by acetazolamide (Acz) is able to prevent HPV in the unanesthetized animal. Ten chronically tracheotomized, conscious dogs were investigated in three protocols. In all protocols, the dogs breathed 21% O2for the first hour and then 8 or 10% O2for the next 4 h spontaneously via a ventilator circuit. The protocols were as follows: protocol 1: controls given no Acz, inspired O2fraction (FiO2) = 0.10; protocol 2: Acz infused intravenously (250-mg bolus, followed by 167 μg·kg−1·min−1continuously), FiO2= 0.10; protocol 3: Acz given as above, but with FiO2reduced to 0.08 to match the arterial Po2(PaO2) observed during hypoxia in controls. PaO2was 37 Torr during hypoxia in controls, mean pulmonary arterial pressure increased from 17 ± 1 to 23 ± 1 mmHg, and pulmonary vascular resistance increased from 464 ± 26 to 679 ± 40 dyn·s−1·cm−5( P < 0.05). In both Acz groups, mean pulmonary arterial pressure was 15 ± 1 mmHg, and pulmonary vascular resistance ranged between 420 and 440 dyn·s−1·cm−5. These values did not change during hypoxia. In dogs given Acz at 10% O2, the arterial PaO2was 50 Torr owing to hyperventilation, whereas in those breathing 8% O2the PaO2was 37 Torr, equivalent to controls. In conclusion, Acz prevents HPV in conscious spontaneously breathing dogs. The effect is not due to Acz-induced hyperventilation and higher alveolar Po2, nor to changes in plasma endothelin-1, angiotensin-II, or potassium, and HPV suppression occurs despite the systemic acidosis with CA inhibition.

The objective of this study was to determine whether endothelin-A receptor blockade (ETAB) impairs hemodynamic and hormonal regulation compared with controls and angiotensin II receptor blockade (AT1B) during hypotensive hemorrhage in dogs under isoflurane-nitrous oxide anesthesia.Six dogs were studied in four protocols: (1) control experiments (controls); (2) ETA blockade using ABT-627 (ETAB); (3) AT1 blockade using losartan (AT1B); and (4) combined AT1B and ETAB (AT1B + ETAB). After a 30-min awake period, isoflurane-nitrous oxide anesthesia was established (1.3 minimum anesthetic concentration). After 60 min of anesthesia, 20 ml blood/kg body weight was withdrawn within 5 min, and the dogs were observed for another hour. Thereafter, the blood was retransfused, and the dogs were observed for a final hour.Anesthesia: Cardiac output decreased in all protocols, whereas mean arterial pressure decreased more in AT1B and AT1B + ETAB than in controls and ETAB. Hemorrhage: After 60 min, cardiac output had decreased less in controls than in all other protocols. Mean arterial pressure decreased more during ETAB than in controls, but most severely during AT1B and AT1B + ETAB. Angiotensin II increased further only in controls and ETAB, whereas vasopressin and catecholamines increased similarly in all protocols. Retransfusion: Mean arterial pressure remained below controls in all protocols but was lowest when the AT1 receptor was blocked. Cardiac output fully recovered in all but the ETAB protocol.ETAB impairs long-term hemodynamic regulation after hemorrhage and retransfusion during anesthesia despite an activation of vasoconstrictive hormones. This suggests that endothelins have a role in long-term cardiovascular regulation. AT1B impairs both short- and long-term blood pressure regulation during anesthesia and after hemorrhage.

The Compressed Baryonic Matter (CBM) experiment at the future FAIR accelerator complex at Darmstadt is being designed for a comprehensive measurement of hadron and lepton production in heavy-ion collisions from 8-45 AGeV beam energy, producing events with large track multiplicity and high hit density. The setup consists of several detectors including as tracking detectors the silicon tracking system (STS), the muon detector (MUCH) or alternatively a set of Transition Radiation Detectors (TRD). In this contribution, the status of the track reconstruction software including track finding, fitting and propagation is presented for the MUCH and TRD detectors. The track propagation algorithm takes into account an inhomogeneous magnetic field and includes accurate calculation of multiple scattering and energy losses in the detector material. Track parameters and covariance matrices are estimated using the Kalman filter method and a Kalman filter modification by assigning weights to hits and using simulated annealing. Three different track finder algorithms based on track following have been developed which either allow for track branches, just select nearest hits or use the mentioned weighting method. The track reconstruction efficiency for central Au+Au collisions at 25 AGeV beam energy using events from the UrQMD model is at the level of 93-95% for both detectors.