Renal redox dysregulation in AKI: application for oxidative stress marker of AKI.

Oxidative stress is a major determinant of acute kidney injury (AKI); however, the effects of an AKI on renal redox system are unclear, and few existing AKI markers are suitable for evaluating oxidative stress. We measured urinary levels of the redox-regulatory protein thioredoxin 1 (TRX1) in patients with various kinds of kidney disease and in mice with renal ischemia-reperfusion injury. Urinary TRX1 levels were markedly higher in patients with AKI than in those with chronic kidney disease or in healthy subjects. In a receiver operating characteristic curve analysis to differentiate between AKI and other renal diseases, the area under the curve for urinary TRX1 was 0.94 (95% confidence interval, 0.90-0.98), and the sensitivity and specificity were 0.88 and 0.88, respectively, at the optimal cutoff value of 43.0 µg/g creatinine. Immunostaining revealed TRX1 to be diffusely distributed in the tubules of normal kidneys, but to be shifted to the brush borders or urinary lumen in injured tubules in both mice and humans with AKI. Urinary TRX1 in AKI was predominantly in the oxidized form. In cultured human proximal tubular epithelial cells, hydrogen peroxide specifically and dose dependently increased TRX1 levels in the culture supernatant, while reducing intracellular levels. These findings suggest that urinary TRX1 is an oxidative stress-specific biomarker useful for distinguishing AKI from chronic kidney disease and healthy kidneys.

[The use of rocuronium in a patient with Becker muscular dystrophy].

We report a case of thoracoscopic pulmonary resection for pneumothorax in a patient with Becker muscular dystrophy The sensitivity of nondepolarizing muscle relaxant in a patient with muscle dystrophy is reportedly higher than in a patient without muscle disease, and the duration of the effect is known to be prolonged. In a 26-year-old man (height 160 cm, weight 39 kg) with Becker muscular dystrophy, general anesthesia was induced with target controlled infusion of propofol (3.0 microg x ml(-1)) and 0.4 microg x kg(-1) of min(-1) of remifentanil. A small amount of rocuronium was also administered additionally until TOF ratio reached to 0%. Total amount of rocuronium was 20 mg (0.5 mg x kg(-1)) for intubation with a double-lumen tracheal tube. The duration of surgery was 68 min. We confirmed 84% recovery of TOF ratio 90 min after injection of rocuronium, and extubated the patient without reversal of rocuronium. We found that the maximum concentration in the plasma or effective site (Cp/Ce) of rocuronium was reached at the time of intubation.

[Clinical application of urinary redox regulating protein, thioredoxin].

Thioredoxin (TRX) is a redox-regulating protein, induced in response to oxidative stress. The function of TRX in the urine is unknown. We show here that urinary TRX begin to increase within one hour and peaks within two hours after ischemia reperfusion of mice. Serum levels of TRX are not changed by the ischemia/reperfusion. In a time-dependent study of immunohistochemistry, TRX appears diffusely in the tubular cytosol in sham-operated mice. On the other hand, immediately after renal ischemia/reperfusion, TRX become to eccentrically-locate in the apical side of the tubular cytosol, and then TRX is detected only in the urinary lumen. In contrast, when we examine the immunolocalization of glutaredoxin, which is a member of the TRX superfamily, we find that the immunoreactivity is unchanged after renal ischemia/reperfusion. Northern blotting and in situ hybridization show that epithelial cells constitutively express TRX mRNA but neither expression levels nor distribution are altered by ischemia-reperfusion. An overexpression of hTRX in transgenic mice attenuates the reperfusion injury. These data suggests that TRX is produced in tubular cells in a steady state. The increase in the urine after ischemia-reperfusion is not mediated by a de novo induction of TRX mRNA but by a discharge of TRX protein from tubular epithelial cells. TRX is useful for the diagnosis of AKI in association with oxidative stress.

[Educational efficacy of computer software showing the effect-site concentration of fentanyl in anesthesia training].

BACKGROUND: We investigated the efficacy of computer software showing the effect-site concentration of fentanyl in anesthesia training. METHODS: All patients were randomly divided into the following three groups. Anesthesia management was performed with a pharmacokinetic simulation program by anesthesia residents with experience in using it for less than 3 months (P (+) group, n = 32). Anesthesia management was performed without a pharmacokinetic simulation program by anesthesia residents with experience in using it for less than two weeks (P (-) group, n = 25). Anesthesia management was performed without a pharmacokinetic simulation program by anesthesia residents with no experience in using it, under supervision of experienced anesthesiologists (C group, n = 22). We measured the effect-site concentration of fentanyl (Ce of fentanyl) at the end of surgery, intraoperative total doses of fentanyl and propofol, the time required from the end of operation to extubation, and frequency of analgesics required within 24 hours. RESULTS: Total doses of fentanyl were significantly more in P (+) group than in other two groups. Ce of fentanyl were significantly more in P (+) group than in other two groups. CONCLUSIONS: A pharmacokinetic simulation program is useful for anesthesia residents.

[Perioperative anesthetic management of a patient with multiple sclerosis].

We report general anesthesia for a patient with multiple sclerosis (MS). A 40-year-old male patient with a 13-year history of MS was scheduled for laparoscopic surgery. The symptoms of MS had been exacerbated during feverish state or under surgical stress in the previous surgeries. To prevent surgical stress response and postoperative fever, we performed epidural anesthesia with continuous intravenous infusion of propofol and fentanyl during surgery. Flurbiprofen axetil was used for slight postoperative fever. There was no clinical exacerbation of MS during perioperative period. In conclusion, appropriate control of surgical stress and prevention of fever are important for perioperative anesthetic management of patients suffering from MS.

[Continuous intravenous administration of fentanyl reduces tenesmus after transurethral resection of the prostate (TUR-P)].

BACKGROUND: The relief from tenesmus is important after transurethral resection of the prostate (TUR-P). We evaluated the effect of continuous intravenous administration of fentanyl on the tenesmus. METHODS: Eleven patients receiving fentanyl infusion (fentanyl group) were compared with fourteen patients without fentanyl infusion (control group) retrospectively. All patients underwent TUR-P under spinal anesthesia with hyperbaric 0.5% bupivacaine 2.2-2.8 ml. In the fentanyl group, fentanyl infusion 25 microg x hr(-1) was started followed by fentanyl 50 microg administration postoperatively. RESULTS: In the fentanyl group, NSAIDs were needed in only one patient. Eleven patients in the control group, however, required NSAIDs and three of them needed additional pentazocine administration. The required amount of NSAIDs per patient was significantly smaller in the fentanyl group (Mann-Whitney U test, P < 0.01). In the fentanyl group, one patient had slight nausea but needed no care. Other side effects, such as respiratory depression, hypotension, bradycardia and somnolence were not observed. CONCLUSIONS: Continuous intravenous administration of fentanyl was very effective and safe enough for the tenesmus after TUR-EP.

[Two cases of atraumatic iliopsoas hematoma].

We report two cases of atraumatic iliopsoas hematoma. First patient was a 76-year-old man admitted to our hospital from appetite loss. Blood transfusion did not improve his anemia. Five days after admission, suddenly he went into shock. CT scan revealed ileopsoas hematoma. He died from hemorrhagic shock in spite of conservative therapy. Second patient was a 70-year-old man admitted because of acute heart failure. Continuous hemodiafiltration was required to relieve anuria. The next day, he developed left leg and hip pain. CT scan revealed ileopsoas hematoma and he received CT guided aspiration drainage for decompression, but almost 7 days were needed to achieve successful pain control. In a case of iliopsoas hematoma, early diagnosis and adequate choise of therapy are necessary to improve prognosis of patients.