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Publications (8)6.67 Total impact

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    ABSTRACT: Purpose: This study investigated the effects of direct hemoperfusion with polymyxin B-immobilized fibers (PMX-DHP) on respiratory impairment in endotoxemic pigs. Materials and Methods: Thirteen anesthetized, mechanically ventilated pigs were divided into PMX-DHP (n=7) and control (n=6) groups. All pigs were hemodynamically monitored with the pulse index contour cardiac output (PiCCO) system (Pulsion Medical Systems, Munich, Germany) and infused intravenously with live Escherichia coli (LD50). In the PMX-DHP group, an arteriovenous extracorporeal circuit with a PMX column was applied for 30 to 150 minutes after endotoxin injection. We analyzed the laboratory data, arterial blood gas levels, and PiCCO variables (extravascular lung water [EVLW] and pulmonary vascular permeability index [PVPI]). Furthermore, we performed computed tomography of the chest in all pigs. The data were statistically analyzed with Student's t-test, the chi-square test, and the Mann-Whitney U-test. Results: With PMX-DHP endotoxemia significantly decreased and blood pressure increased 150 minutes after endotoxin injection. PiCCO revealed more cases of decreased EVLW in the PMX-DHP group. PVPI increased after endotoxin infusion in both groups. Computed tomography showed improvements in the PMX-DHP group. The survival rate was greater in the PMX-DHP group (100%) than in the control group (71%). Conclusion: PMX-DHP is effective for treating respiratory impairment and contributes to the decreased mortality rate in the endotoxemic pigs.
    01/2014; 81(3):130-8.
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    ABSTRACT: Tramadol is an atypical opioid analgesic widely used in small animal practice. This study was designed to determine the effect of a single intravenous (IV) dose of tramadol on the minimum alveolar concentration (MAC) of sevoflurane in dogs. Six beagle dogs were anesthetized twice to determine the sevoflurane MAC with or without an administration of tramadol (4 mg/kg, IV) at 7 days interval. The sevoflurane MAC was determined using a tail clamp method in each dog ventilated with positive pressure ventilation. The tramadol administration produced a significant reduction in the sevoflurane MAC by 22.3 ± 12.2% (1.44 ± 0.28% with tramadol versus 1.86 ± 0.30% without tramadol, P=0.010). This MAC reduction had been determined from 122 ± 19 to 180 ± 41 min following the tramadol administration. During this period, the plasma concentrations of tramadol and its metabolite, O-desmethyltramadol (M1), decreased from 429 ± 64 to 332 ± 55 ng/ml and from 136 ± 24 to 114 ± 68 ng/ml, respectively, but these changes were not statistically significant. There was no significant difference in heart rate, mean arterial blood pressure and SpO(2) between the control and tramadol treatment. The dogs that received tramadol treatment sometimes breathed spontaneously. Therefore, their respiratory rates significantly increased, and PETCO(2) decreased during the MAC determination. In conclusion, the single IV dose of tramadol produced a significant reduction in the sevoflurane MAC in dogs.
    Journal of Veterinary Medical Science 01/2013; · 0.88 Impact Factor
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    ABSTRACT: Anesthetic and cardio-respiratory effects of medetomidine, lidocaine, butorphanol and propofol total intravenous anesthesia (MLBP-TIVA) were evaluated in horses undergoing an experimental surgery. Ten horses were pre-medicated with an intravenous injection (IV) of medetomidine (5 μg/kg) and butorphanol (20 μg/kg). Anesthesia was induced by administration of 1% propofol (3 mg/kg, IV) at a rate of 1 mg/kg/min (n=5, group-1) or 2% propofol administered at a rate of 6 mg/kg/min (n=5, group-2) following administration of lidocaine (1 mg/kg, IV) and then maintained by infusions of propofol, medetomidine (3.5 μg/kg/hr), lidocaine (3 mg/kg/hr) and butorphanol (24 μg/kg/hr). The mean durations of anesthesia and propofol infusion rate required for maintaining surgical anesthesia were 130 ± 17 min and 0.10 ± 0.01 mg/kg/min in group-1 and 129 ± 14 min and 0.10 ± 0.02 mg/kg/min in group-2. Four in group-1 and 2 horses of group-2 paddled following recumbency during induction of anesthesia. The median quality scores (0: poor-4: excellent) for induction were 3 and for recovery (0: unable to stand-5: excellent) were 4 for both groups. During transition to anesthesia (the first 20-min period after the induction), it was uneventful in group-2 while all horses showed a light plane of anesthesia in group-1. The quality score (0: poor-3: excellent) for the transition to anesthesia in group-2 was significantly higher than in group-1 (median 3 versus 1, P=0.009). Heart rate and arterial blood pressure were maintained within acceptable ranges but hypercapnea occurred during anesthesia in both groups. In conclusion, MLBP-TIVA may provide clinically useful surgical anesthesia in horses. A rapid induction with propofol may improve the qualities of induction and transition to MLBP-TIVA.
    Journal of Veterinary Medical Science 10/2012; · 0.88 Impact Factor
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    ABSTRACT: Contrast-enhanced magnetic resonance (MR) imaging with a new liver-specific contrast agent gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA; EOB·Primovist®) was studied in 14 normal beagles and 9 dogs with focal liver lesions. Gd-EOB-DTPA accumulates in normally functioning hepatocytes 20 min after injection. As with Gd-DTPA, it is also possible to perform a dynamic multiphasic examination of the liver with Gd-EOB-DTPA, including an arterial phase and a portal venous phase. First, a reliable protocol was developed and the appropriate timings for the dynamic study and the parenchymal phase in normal dogs using Gd-EOB-DTPA were determined. Second, the patterns of these images were evaluated in patient dogs with hepatic masses. The optimal time of arterial imaging was from 15 s after injection, and the optimal time for portal venous imaging was from 40 s after injection. Meanwhile, the optimal time to observe changes during the hepatobiliary phase was from 20 min after injection. In patient dogs, 11 lesions were diagnosed as malignant tumors; all were hypointense to the surrounding normal liver parenchyma during the hepatobiliary phase. Even with a low-field MR imaging unit, the sequences afforded images adequate to visualize the liver parenchyma and to detect tumors within an appropriate scan time. Contrast-enhanced MR imaging with Gd-EOB-DTPA provides good demarcation on low-field MR imaging for diagnosing canine focal liver lesions.
    Veterinary Radiology &amp Ultrasound 05/2012; 53(4):371-80. · 1.41 Impact Factor
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    ABSTRACT: It is well known that heart rate or arterial blood pressure may increase in response to surgical stimulation despite the absence of a purposeful movement. However, there is limited information regarding anesthetic requirement for blunting adrenergic response in dogs. This study was designed to compare the minimum alveolar concentrations of sevoflurane required to prevent autonomic response (MAC-BAR) and purposeful movement (MAC) in dogs. Sevoflurane MAC-BAR and MAC were determined in 5 beagle dogs by judging dogs' response to a noxious electrical stimulus applied to the gingiva. The sevoflurane MAC-BAR was significantly higher than MAC (3.33 ± 0.48 vs 2.10 ± 0.28%, P=0.005). These results suggested that autonomic responses occurred at sevoflurane anesthetic concentrations at which purposeful movements were absent.
    Journal of Veterinary Medical Science 11/2011; 74(4):507-11. · 0.88 Impact Factor
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    ABSTRACT: Cardiovascular effects of tramadol were evaluated in dogs anesthetized with sevoflurane. Six beagle dogs were anesthetized twice at 7 days interval. The minimum alveolar concentration (MAC) of sevoflurane was earlier determined in each dog. The dogs were then anesthetized with sevoflurane at 1.3 times of predetermined individual MAC and cardiovascular parameters were evaluated before (baseline) and after an intravenous injection of tramadol (4 mg/kg). The administration of tramadol produced a transient and mild increase in arterial blood pressure (ABP) (P=0.004) with prolonged increase in systemic vascular resistance (SVR) (P<0.0001). Compared with baseline value, mean ABP increased significantly at 5 min (119% of baseline value, P=0.003), 10 min (113%, P=0.027), and 15 min (111%, P=0.022). SVR also increased significantly at 5 min (128%, P<0.0001), 10 min (121%, P=0.026), 30 min (114%, P=0.025), 45 min (113%, P=0.025) and 60 min (112%, P=0.048). Plasma concentrations of tramadol were weakly correlated with the percentage changes in mean ABP (r=0.642, P<0.0001) and SVR (r=0.646, P<0.0001). There was no significant change in heart rate, cardiac output, cardiac index, stroke volume, pulmonary arterial pressure, right atrial pressure and pulmonary capillary wedge pressure. In conclusion, the administration of tramadol produces a prolonged peripheral vascular constriction in dogs anesthetized with sevoflurane, which is accompanied with a transient and mild increase in arterial blood pressure. It also indicated that the degree of vasoconstriction might depend on the plasma concentration of tramadol.
    Journal of Veterinary Medical Science 08/2011; 73(12):1603-9. · 0.88 Impact Factor
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    ABSTRACT: We measured the plasma D-dimer (DD) concentration in 205 dogs. Simultaneously, fibrinogen/fibrin degradation products (FDPs) concentration, platelet (PLT) count, prothrombin time (PT), activated partial thromboplastin time (APTT), and plasma concentrations of fibrinogen (Fib) were measured in the same dogs. From these results, we were able to divide the animals into four groups: control (healthy dogs, n=18), pre-disseminated intravascular coagulation (preDIC) (n=20), disseminated intravascular coagulation (DIC) (n=21), and other (n=146). Significant differences in plasma DD concentration were found among the four groups: control, 0.45 ± 0.46 µg/ml (reference range, 0-1.37); preDIC, 5.0 ± 4.8 µg/ml; DIC, 16.3 ± 12.2 µg/ml; and other, 1.5 ± 2.7 µg/ml. A weak positive correlation (r=0.62) was found between FDPs and DD concentrations in the DIC group. As a DIC diagnostic test, the PLT/APTT/FDPs/DD combination had the highest accuracy of 100%, with a sensitivity of 73% and a specificity of 97%. We propose the use of FDPs and DD concentrations as part of the DIC diagnostic test panel, with DD and FDPs to provide accurate diagnosis.
    Journal of Veterinary Medical Science 05/2010; 72(10):1301-6. · 0.88 Impact Factor
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    ABSTRACT: A 2-year-old castrated miniature Dachshund dog was presented to the Rakuno Gakuen Veterinary Teaching Hospital for diagnosis of progressive hindlimb paresis and ataxia. There was no thoracolumbar intervertebral disk hernia and magnetic resonance imaging revealed an intramedullary spinal cord lesion at the ninth and tenth thoracic vertebrae. Following surgical excision of the neoplasm, there was minor amelioration of neurological signs, but forelimb function was not recovered. The extracted tumor was histopathlogically diagnosed as spinal nephroblastoma.
    Journal of Veterinary Medical Science 01/2007; 68(12):1383-5. · 0.88 Impact Factor