Biomedical subjects

Kazuo Hanaoka

Publications and source records attributed to Kazuo Hanaoka.

At least 19 recordsLinked to original sources

PubMed2007

Age and sex-related differences in dose-dependent hemodynamic response to landiolol hydrochloride during general anesthesia.

OBJECTIVE: Landiolol hydrochloride is a new ultra-short-acting beta(1)-adrenergic receptor blocking agent that is used for patients with tachycardia during general anesthesia. The hemodynamic response to a beta-adrenergic receptor blocking agent is generally dependent on the subject. In the present investigation we investigated the effects of age and sex on the hemodynamic response to different doses of landiolol. METHODS: Following a persistence of tachycardia for more than 1 min, landiolol was infused at 0.03125, 0.0625 and 0.125 mg kg(-1) min(-1) for 1 min followed by 0.01, 0.02 and 0.04 mg kg(-1)min(-1) for 10 min in groups L, M and H, respectively. Heart rate (HR), systolic (sBP) and diastolic blood pressure (dBP) were recorded each minute during the procedure. The respective changes were evaluated using logistic analysis with the equation Y(t) = p + (q - p)/[1 + exp {4m/(q - p))(k - t)}], where p, q, m and k indicate the upper asymptote, lower asymptote, maximum slope and time at the maximum slope. RESULTS: Parameters q and k for HR in group H were smaller than those in group L, whereas the parameters for sBP and dBP were unchanged among the three groups. Parameter q for HR in group H decreased with age of the patient. There was no significant difference in the landiolol-induced change in HR between males and females. CONCLUSION: The hemodynamic response to landiolol is reliably modeled by the logistic function, especially in terms of HR. Landiolol causes a rapid and dose-dependent decrease in HR, whereas landiolol-induced changes in sBP and dBP are independent of dose. The landiolol-induced decrease in HR becomes larger with aging, but shows no sex difference. The logistic model may be useful for studying hemodynamic responses to landiolol based on age and sex differences, and may allow development of an improved monitoring system. IMPLICATION STATEMENT: The logistic function reliably represents the hemodynamic responses to landiolol. Landiolol reduces HR rapidly and in a dose-dependent manner whereas landiolol-induced changes in sBP and dBP are independent of dose. A larger decrease in HR is caused by landiolol in elderly patients, but there is no sex difference in the landiolol-induced change in HR.

Adrenergic beta-Antagonists↗

PubMed2007

Encephalopathy and rhabdomyolysis induced by iotrolan during epiduroscopy.

PURPOSE: We describe a complication of epiduroscopy with encephalopathy and rhabdomyolysis associated with the contrast medium iotrolan. CLINICAL FEATURES: A 76-yr-old man with failed back surgery syndrome underwent epiduroscopy. Sufficient lysis could not be achieved in the epidural space above the level of L4 due to dense adhesions and scar tissue. After epidural injections of iotrolan and mepivacaine, he developed motor weakness and hypoesthesia in both legs, which lasted for three hours. He also became confused, agitated, disoriented, and developed neck stiffness and tremors involving the head and legs. Computed tomography revealed diffuse contrast enhancement within the intracranial cerebrospinal fluid (CSF) spaces, indicating an intraoperative dural tear. Marked increases in serum creatinine phosphokinase and myoglobin indicated subsequent acute rhabdomyolysis. Crystalloid infusion and semi-recumbent positioning facilitated iotrolan absorption from the CSF, and the patient recovered uneventfully. CONCLUSIONS: Dural tear during epiduroscopy may allow access of contrast media into the CSF. Neurotoxicity secondary to iotrolan within the CSF was a likely contributing factor to the encephalopathy and subsequent rhabdomyolysis. This is an instructive example of the importance of diagnosing inadvertent dural tear during epiduroscopy under iotrolan, for avoidance of adverse events such as encephalopathy and rhabdomyolysis.

Acute Disease↗

PubMed2006

Inhibition of morphine tolerance by processed Aconiti tuber is mediated by kappa-opioid receptors.

Previously, we found that processed Aconiti tuber (PAT) could inhibit morphine tolerance in mice. In the present study, we investigated mechanisms underlying this effect. Mice received subcutaneous (s.c.) morphine (10 mg/kg) and oral PAT at a subanalgesic dose (0.3 g/kg), once a day for 12 days. Additional PAT-treated groups received morphine and PAT, at 120 min after pretreatment with s.c. clocinnamox mesylate (C-CAM) (0.5 mg/kg), or nor-binaltorphimine (nor-BNI) (5 mg/kg). The antinociceptive effect was assessed with the tail pressure test, at 60 min after the daily s.c. morphine injections were given. In the placebo-treated group, repeated morphine injections caused morphine tolerance, and morphine antinociception was abolished by day 6, whereas in PAT-treated groups, significant antinociception was maintained until day 12, suggesting that PAT inhibited morphine tolerance, thereby sustaining morphine antinociception. C-CAM, a selective mu-opioid receptor (MOR) antagonist, blocked morphine antinociception whereas nor-BNI, a selective kappa-opioid receptor (KOR) antagonist, did not. However, both C-CAM and nor-BNI could block the antinociception maintained by the morphine-PAT combination. Results of the study suggested that chronic treatment with PAT at a subanalgesic dose maintained MOR-mediated morphine antinociception by attenuating development of morphine tolerance, and that this tolerance-attenuating effect of PAT was mediated by KOR.

Aconitum↗

PubMed2006

Major histocompatibility complex haplotype is associated with postherpetic pain in mice.

BACKGROUND: Postherpetic neuralgia is one of the major complications of herpes zoster caused by the reactivation of varicella-zoster virus and is characterized by severe pain. The authors previously showed the association of a human major histocompatibility complex (MHC) haplotype with postherpetic neuralgia. This study was performed to experimentally confirm the role of MHC haplotype in the development of postherpetic pain using a mouse model of postherpetic pain, which corresponds to postherpetic neuralgia. METHODS: BALB/c mice (MHC haplotype: H-2), C57BL/6 mice (MHC haplotype: H-2), and BALB/b mice, a congenic BALB/c strain with H-2, were used. Herpes simplex virus type I was transdermally inoculated on the hind paw. Unilaterally zosteriform skin lesion and pain-related responses (acute herpetic pain) were caused, and some mice showed pain-related responses (postherpetic pain) after the cure of skin lesions. Herpes simplex virus type I antigen and CD3-positive cells were immunostained in the dorsal root ganglion in the acute phase. RESULTS: The incidence (78%) of postherpetic pain in C57BL/6 mice was significantly higher than that (35%) in BALB/c mice (P = 0.004, odds ratio = 6.7). Furthermore, the incidence of postherpetic pain in BALB/b (H-2) was similar to that in C57BL/6. Herpes simplex virus type I antigen-positive cells were less in the dorsal root ganglion of C57BL/6 mice than that of BALB/c mice. CD3-positive T cells were more in the dorsal root ganglion of C57BL/6 mice than BALB/c mice. CONCLUSIONS: These results suggest that the MHC haplotype (H-2) is involved in the incidence of postherpetic pain, and CD3-positive T cells may play a role in its pathogenesis.

Animals↗

PubMed2006

Starling-effect-independent lusitropism index in canine left ventricle: logistic time constant.

The logistic time constant (tau(L)) has been proposed as a better index of the rate of left ventricular (LV) relaxation or lusitropism than the conventional monoexponential time constant (tau(E)). However, whether and how the Frank-Starling effect influences tau(L) remains to be elucidated. We compared the effect of LV volume (LVV) loading on both logistic and monoexponential fittings. The isovolumic LV relaxation pressure curves from the maximum negative time derivative of pressure (-dP/dt(max)) were analyzed at 3 different end-points at 4 LVVs of 10, 12, 14, and 16 mL in 8 excised, cross-circulated canine hearts. We found that the logistic fitting was superior to the monoexponential fitting at all LVVs and end-points. LVV loading did not affect tau(L) but affected tau(E) slightly. Although the advancing end-point increased both tau(L) and tau(E), the increases were significantly smaller for tau(L) than for tau(E) at all LVVs. Moreover, the changes in both the amplitude constants and nonzero asymptotes with the advancing end-point were significantly smaller for the logistic fitting than for the monoexponential fitting. We conclude that tau(L) served as a more reliable index of lusitropism that is independent of the change in LVV loading or the Frank-Starling effect.

Animals↗

PubMed2006

The characteristics of intravenous adenosine-induced antinociception in a rabbit model of acute nociceptive pain: a comparative study with remifentanil.

BACKGROUND: Adenosine and remifentanil are potent IV analgesics with ultrashort half-lives. The antinociceptive effect of IV adenosine has not been clearly characterized. We compared the antinociceptive effects of adenosine and remifentanil in rabbits. METHODS: Sixteen rabbits, placed on a sling allowing reasonably free movement, received IV adenosine (400 microg x kg(-1) x min(-1)) or remifentanil (0.4 microg x kg(-1) x min(-1)) over 240 min. RESULTS: Both drugs produced profound antinociception, as assessed by the number of animals unresponsive to clamping the forepaw and the electrical stimulation threshold of escape movement. With remifentanil, the antinociceptive effect increased rapidly, reaching its peak at 60 min, and then began to decline despite continued infusion. After stopping the infusion, it decreased rapidly and disappeared within 30 min. The vasodilating effect of IV adenosine was immediate in onset and ultrashort in duration. The antinociceptive effect of adenosine increased slowly but progressively during the infusion, reaching its peak only when the infusion ended. Then it decreased slowly over the following 360 min after terminating the infusion. CONCLUSION: Remifentanil had a rapid onset and short duration of action, and probably showed signs of tolerance development, whereas the antinocieptive effect of adenosine was slow in onset and long-lasting, despite its ultrashort plasma half-life and the immediate on-off profiles of its vasodilating effect.

Adenosine↗

PubMed2006

[Postponed or canceled drug challenge tests and side effects of the test drug--a report of four cases].

Drug challenge test (DCT) is performed to evaluate chronic pain pharmacologically and determine its medical treatment. One test drug is administered in one day for DCT and characterization of the test drug. Four patients developed side effects of the test drugs for DCT in whom other drug tests were postponed or canceled. A 58-year-old man with multiple arthritis of rheumatic arthritis and fibromyalgia had headache, nausea, and vomiting all day after ketamine test. A 76-year-old man with chronic general pain and failed back surgery syndrome had vomiting and abdominal discomfort two hours after morphine test and had redness and itching on his bilateral forearms the following day. A 78-year-old man with chronic lumbar and right lower limb pain due to L 4-5 lumbar disc herniation and postherpetic neuralgia felt dizzy, fell down and bruised on his lower back and left knee twelve hours after morphine test. A 32-year-old woman with chronic pelvic pain had skin eruption on her thigh the day after phentolamine test. Although the amount of the test drug in DCT is small and its half-life is short, long-term side effects might occur. We should decrease the amounts or frequencies of ketamine and morphine, and administer them taking long intervals before other tests.

Adult↗

PubMed2006

[Outline and effectiveness of support system in the surgical center by supply, processing and distribution center (SPD)].

Supply, Processing and Distribution system had been introduced to surgical center (the University of Tokyo Hospital) since October of 2002. This system had reduced stock for medicine and materials and decreased medical cost dramatically. We designed some kits for therapeutic drugs related to anesthesia. They were prepared for general anesthesia, epidural and spinal anesthesia, and cardiovascular anesthesia, respectively. One kit had been used for one patient, and new kits were prepared in the anesthesia preparation room by pharmaceutical department staffs. Equipment, for general anesthesia as well as epidural and spinal anesthesia, and central catheter set were also designed and provided for each patient by SPD system. According to the questionnaire of anesthesia residents before and after introduction of SPD system, the time spent for anesthesia preparation had been reduced and 92.3% residents had answered that preparation for anesthesia on the previous day was getting easier. Most of the anesthesia residents had been less stressed after introduction of SPD system. Beside the dramatic economical effect, coordination with SPD system and pharmaceutical department reduced anesthesia preparation time and stress of the staff. Introduction of Support system of SPD to surgical center is important for safe and effective management of operating rooms.

Anesthesia↗

PubMed2006

[Post-brain angiographic asymptomatic pulmonary embolism diagnosed before general anesthesia].

A 58-year-old man was scheduled for resection of a brain tumor. He had undergone brain angiography two days before the operation. His right femoral artery punctured for the insertion of a catheter, had been compressed with a sponge for six hours after the brain angiography. He had gone without food for 13 hours and drink for 11 hours before entering the operating room. He was given 2.5 mg of midazolam im as premedication. Though we found his SpO2 value decreased to 88-90%, he did not complain of any clinical symptoms. Arterial blood gas (ABG) analysis showed PaO2 of 60 mmHg with room air. We asked him to take deep breaths for five minutes, but his ABG analysis continued to show hypoxia. Therefore, his scheduled operation was canceled in order to investigate the cause of hypoxia. As chest enhanced computed tomography revealed thrombosis of 3 cm in length in the A 3 artery of his right lung, we diagnosed pulmonary embolism and treated it with continuous intravenous injection of heparin. Pulmonary thromboembolism in this case might have been due to femoral vein compression, vein congestion during extended periods of bed rest after the brain angiography, deep leg vein thrombosis produced by femoral artery injury, and dehydration before the operation. Care has to be taken for the onset of pulmonary embolism after angiography through the femoral artery. Measurement of SpO2 is useful for the early diagnosis of asymptomatic pulmonary embolism.

Anesthesia, General↗

PubMed2006

[Information and consent sheet of caudal block in the University of Tokyo Hospital].

Caudal block with a local anesthetic through the hiatus sacralis has been performed in patients with chronic low back pain, lower limb pain, anal pain, and pelvic pain due to spinal canal stenosis, lumbar disc herniation, lumbar spondylolisthesis, postherpetic neuralgia, peripheral vascular disease, complex regional pain syndrome and so on. We prepar- ed an information and consent sheet on caudal block in The University of Tokyo Hospital. In the information sheet, we included disease, purpose, methods, outcome, accidental complications of caudal block, other treatments, progress on unperformed case, questions and answers, influence of rejection, and doctor's name. We experienced some cases of boring pain, deterioration of low back pain and lower limb pain, headache, nausea, hypertension, hypotension, and tachycardia as accidental complications of caudal block. In describing some accidental complications, we included boring pain, high intracranial pressure, dural puncture, nerve injury, infection, hemorrhage, embolism, allergy, and heart, lung, brain, liver, and kidney failures. Further, we could refer to the accidental complications of epidural block. However, the rate of each accidental complication has not been known in detail. We should survey the outcome and accidental complication of caudal block prospectively in multiple facilities and provide the patients with useful information.

Anesthesia, Caudal↗

PubMed2006

[Preload and ventricular lusitropism; logistic and monoexponential function fittings].

A logistic function has been found to fit the isovolumic left ventricular (LV) relaxation pressure curve and the isometric relaxation force curve of the papillary muscle much more precisely than the conventional monoexponential function. Therefore, the logistic time constant (tauL) has been proposed as a better index of the rate of cardiac relaxation or lusitropism than the conventional monoexponential time constant (tauE). Many investigators have reported that tauE changes with preloading. We analysed and compared the effect of LV volume (LVV) loading on both logistic and monoexponential fittings and their time constants of the isovolumic LV relaxation pressure curve in the excised, cross-circulated canine hearts. We found that the logistic fitting was superior to the monoexponential fitting at any LVV. LVV loading did not affect tauL at all but affected tauE slightly. The logistic fitting more reliably characterises the lusitropism than the monoexponential fitting, and tauL, serving as a more reliable ventricular lusitropism index, is independent of changes in LVV loading or the Frank-Starling effect.

Anesthesia↗

PubMed2006

[Devices for the relief and evaluation of pain: preface and comments].

Pain is the most popular complaint since the appearance of the human on earth, a very unpleasant feeling sometimes difficult to be treated. Therefore, we have many patients who complain of pain in our hospitals or clinics. When a patient with pain visits our institution, first of all, we must evaluate the grade of pain, and then start to treat the pain of the patient. Of course, we have many devices available to treat the patient with pain. In the following special articles, device for evaluation of pain, spinal stimulation device, device for electrical current therapy (ECT), LASER device for chronic and acute pain, epiduroscopy for lumbago, as well as disposable infusion pump for postoperative pain and cancer pain are described. The mechanism of pain may be understood by patients themselves. However, devices in these articles are very useful for the treatment of pain, especially intractable pain. I feel very happy if these articles contribute greatly for the treatment of patients with pain.

Analgesia, Patient-Controlled↗

PubMed2006

[Acute popliteal arterial occlusion during extracorporeal circulation].

A 79-year-old man underwent aortic arch replacement for thoracic aortic aneurysm. He had a history of smoking, coronary stenting for ischemic heart disease and replacement with artificial blood vessel for abdominal aortic aneurysm. Anesthesia was induced and maintained with midazolam, fentanyl, sevoflurane, and vecuronium. A 20 gage catheter was placed in the right radial artery and a 22 gage catheter in the left posterior tibial artery. Total circulatory arrest under profound hypothermia and retrograde cerebral perfusion were performed using extracorporeal circulation. After finishing anastomosis with artificial blood vessel, he was weaned from extracorporeal circulation. The pressure in the left posterior tibial artery was maintained at 15 mmHg, although the blood pressure in the right radial artery increased gradually. Then, the pressure in the left femoral artery in the operative field was the same as the pressure in the right radial artery. Therefore, we suspected the arterial line occlusion of the left posterior tibial artery. After the operation, we found the left leg and foot pale and cold with no pulsation on the left popliteal, dorsal pedis, and posterior tibial arteries. Further, acute left popliteal arterial occlusion was assessed by means of Doppler and left lower extremity angiography. We immediately performed the balloon-catheter embolectomy. However, as he developed compartment syndrome on the left lower limb due to reperfusion injury postoperatively, fascitomy was performed. On the 58th postoperative day, he was discharged from our hospital. Measurement by Doppler is useful for the early diagnosis of the lower leg arterial occlusion.

Aged↗

PubMed2005

Pain-relieving effects of processed Aconiti tuber in CCI-neuropathic rats.

Neuropathic pain is often refractory to conventional pain therapies and thus requires exploration of effective drugs. We evaluated if processed Aconiti tuber (PAT), a traditional oriental herbal medicine that has been used as an analgesic, relieves neuropathic pain in the rat chronic constriction injury (CCI) model. Ten to 14 days after CCI in the right hind paw, six groups of rats received oral placebo, or PAT at 0.5, 1, 2, 3, or 5 g/kg. Additional groups received oral PAT, 2 g/kg, after pretreatment with intraperitoneal naloxone; intraperitoneal nor-binaltorphimine (norBNI); or intrathecal norBNI. As indicators of mechanical allodynia and thermal hyperalgesia, the pressure threshold of paw withdrawal (PWT) in response to linearly increasing pressure, and latency to paw withdrawal (PWL) in response to radiant heat, were measured before and after drug administration. Oral PAT dose-dependently increased PWT and PWL, which had been decreased due to CCI. The increases in PWT and PWL by oral PAT were inhibited by intraperitoneal and intrathecal norBNI: a selective kappa-opioid receptor antagonist, but not by intraperitoneal naloxone. These results indicate that oral PAT can alleviate mechanical allodynia and thermal hyperalgesia, dose-dependently, via spinal kappa-opioid receptor mechanisms in a rat CCI neuropathic pain model.

Aconitum↗

PubMed2005

Effects of processed Aconiti tuber and its ingredient alkaloids on the development of antinociceptive tolerance to morphine.

Processed Aconiti tuber (PAT) is a herbal medicine that has been widely used as an analgesic since ancient times. We investigated effects of subanalgesic doses of PAT on morphine tolerance in mice. Mice received subcutaneous morphine (10 mg/kg) and oral PAT at subanalgesic doses (0.1 or 0.3 g/kg), once a day for 7 days. Mechanical nociceptive thresholds were measured using the tail pressure test, at 60 min after the daily s.c. morphine injections. In the placebo-treated group, repeated administration of s.c. morphine resulted in development of analgesic tolerance. In the PAT-treated groups, oral PAT attenuated morphine tolerance, dose-dependently. The main ingredient alkaloid of PAT causing its tolerance-attenuating activity was mesaconitine, but other ingredient alkaloids, such as aconitine and hypaconitine, also contributed to this activity. In addition, repeated treatment with PAT could reverse already-developed morphine tolerance. Subanalgesic doses of oral PAT thus can attenuate and reverse morphine tolerance in mice.

Aconitine↗

PubMed2005

Anti-allodynic and anti-hyperalgesic effects of nociceptin receptor antagonist, JTC-801, in rats after spinal nerve injury and inflammation.

The effects of nociceptin/orphanin FQ (N/OFQ) peptide receptor antagonist JTC-801 on allodynia and hyperalgesia were examined in rats in order to explore the involvement of N/OFQ system in these pathological pain states. Tactile allodynia induced by L5/L6 spinal nerve ligation was reversed by both systemic (3-30 mg/kg) and spinal (22.5 and 45 pg) JTC-801 in a dose-dependent manner. Concerning hyperalgesia induced by formalin injection into the hindpaw, JTC-801 dose-dependently suppressed the second phase, but not the first phase, of the licking behavior. Furthermore, systemic JTC-801 reduced Fos-like immunoreactivity in the dorsal horn of the spinal cord (laminae I/II). In conclusion, N/OFQ receptor antagonist JTC-801 exerted anti-allodynic and anti-hyperalgesic effects in rats, suggesting that N/OFQ system might be involved in the modulation of neuropathic pain and inflammatory hyperalgesia.

Aminoquinolines↗

PubMed2005

Analgesic effect of intravenous ATP on postherpetic neuralgia in comparison with responses to intravenous ketamine and lidocaine.

PURPOSE: No study has been performed on the analgesic effect of adenosine 5'-triphosphate (ATP) on postherpetic neuralgia (PHN). We conducted an open-label trial of ATP in patients with PHN, and compared ATP with ketamine and lidocaine. METHODS: Twelve patients with PHN were studied. On separate days, ketamine (0.3 mg.kg(-1)), lidocaine (2 mg.kg(-1)), and ATP (100 microg.kg(-1).min(-1) or less for 120 min) were administrated intravenously. The intensity of spontaneous pain as well as tactile allodynia was assessed using a visual analog scale (VAS). When the VAS score for spontaneous pain was decreased by more than 50%, the patient was classified as a responder. RESULTS: Five, 6, and 6 patients responded to ketamine, lidocaine, and ATP, respectively. In 6 ATP responders, pain relief developed slowly and lasted for 9 (median) h (range: 3-72 h). All 5 ketamine responders and only 1 of 7 ketamine nonresponders responded to ATP (5/5 vs 1/7, P < 0.05, chi2 test) whereas 2 of 6 responders to lidocaine and 4 of 6 nonresponders to lidocaine responded to ATP (2/6 vs 4/6, P > 0.05). The ketamine responders responded to ATP more often than did the lidocaine responders (5/5 vs 2/6, P < 0.05). CONCLUSION: Intravenous ATP exerted slowly developing and long-lasting analgesic effects in half of patients with PHN. Patients with ketamine-responsive PHN were likely to respond to ATP.

Adenosine Triphosphate↗

PubMed2005

Role for cyclooxygenase 2 in the development and maintenance of neuropathic pain and spinal glial activation.

BACKGROUND: Lines of evidence have indicated that cyclooxygenase 2 plays a role in the pathophysiology of neuropathic pain. However, the site and mechanism of its action are still unclear. Spinal glia has also been reported to mediate pathologic pain states. The authors evaluated the effect of continuous intrathecal or systemic cyclooxygenase-2 inhibitor on the development and maintenance of neuropathic pain and glial activation in a spinal nerve ligation model of rats. METHODS: Continuous intrathecal infusion of meloxicam (32 or 320 mug . kg . day) or saline was started immediately after L5-L6 spinal nerve ligation. Mechanical allodynia and thermal hyperalgesia were evaluated on days 4 and 7 postoperatively. Spinal astrocytic activation was evaluated with glial fibrially acidic protein immunoreactivity on day 7. In other groups of rats, continuous intrathecal meloxicam was started 7 days after spinal nerve ligation, and effects on established neuropathic pain and glial activation were evaluated. Last, effects of continuous systemic meloxicam (16 mg . kg . day) on existing neuropathic pain and glial activation were examined. RESULTS: Intrathecal meloxicam prevented the development of mechanical allodynia and thermal hyperalgesia induced by spinal nerve ligation. It also inhibited spinal glial activation responses. In contrast, when started 7 days after the nerve ligation, intrathecal meloxicam did not reverse established neuropathic pain and glial activation. Systemic meloxicam started 7 days after ligation partially reversed neuropathic behaviors but not glial activation. CONCLUSIONS: Spinal cyclooxygenase 2 mediates the development but not the maintenance of neuropathic pain and glial activation in rats. Peripheral cyclooxygenase 2 plays a part in the maintenance of neuropathic pain.

Animals↗