Hiroshi Imamura

Juntendo University, Edo, Tōkyō, Japan

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Publications (217)817.47 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: There is little information on whether living donor liver transplantation (LDLT) reduces the supply of blood to esophagogastric varices. The aim of the present study was to assess the effects of LDLT on esophagogastric varices using both endoscopy and transendoscopic microvascular Doppler sonography (EMDS). Patients and Methods: 16 LDLT recipients were enrolled in the present study. Esophagogastric varices were assessed by endoscopy before and after LDLT. Direct measurement of variceal blood velocity was performed using EMDS in 12 of the 16 patients, and portal vein pressure before and after graft implantation was measured in 10 of them. Results: The median interval between LDLT and endoscopic examination was 129 days (range 20-624). Endoscopy demonstrated improvement of esophageal varices in 15 patients and of gastric varices in 4 of 5 patients assessed. The mean blood flow velocity in esophageal varices after LDLT was significantly lower than that before LDLT (8.8 ± 3.6 vs. 0.9 ± 1.2 cm/s, p < 0.001). The mean portal vein pressure did not decrease significantly after LDLT in comparison with that before LDLT (from 25.2 ± 5.2 to 23.1 ± 3.6 mm Hg, p = 0.22). Conclusion: Although portal vein pressure does not decrease immediately after left lobe LDLT, esophagogastric varices are ameliorated after a few months, and variceal blood flow velocity is reduced in almost all patients. © 2014 S. Karger AG, Basel.
    Digestive surgery 10/2014; 31(4-5):283-290. DOI:10.1159/000366230 · 1.37 Impact Factor
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    ABSTRACT: Although duct-to-mucosa pancreatojejunostomy has been considered safer than other techniques, this procedure is particularly difficult when the pancreatic duct is small. It has therefore become increasingly necessary to develop a simple mucosal sutureless pancreatojejunostomy technique to replace the conventional hand-sewing one. Two hundred fourteen patients who underwent mucosal sutureless pancreatojejunostomy were classified into two groups: those with a normal pancreatic duct diameter (less than 3 mm, n = 97) and those with a dilated pancreatic duct (3 mm or greater, n = 117). The rate of clinically significant pancreatic fistula (Grade B or C by the International Study Group on Pancreatic Fistula definition) among the patients as a whole was 8 per cent. The overall incidence of pancreatic fistula was significantly higher in the patients with a pancreatic duct diameter of less than 3 mm than in those with a pancreatic duct diameter of 3 mm or greater. However, the incidence of clinically significant pancreatic fistula did not differ between the groups (less than 3 mm, 11%; 3 mm or greater, 5%; P = 0.09). Grade C pancreatic fistula developed in one patient with a pancreatic duct diameter of less than 3 mm and in two with a pancreatic duct diameter 3 mm or greater. Although two patients required reoperation, all of the fistulas were cured and the postoperative mortality rate related to pancreatoduodenectomy was zero. Mucosal sutureless pancreatojejunostomy combined with pancreatic duct stenting is associated with a low rate of clinically significant pancreatic fistula even in patients with a small pancreatic duct diameter less than 3 mm.
    The American surgeon 02/2014; 80(2):149-154. · 0.92 Impact Factor
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    ABSTRACT: A 58-year-old man was transferred to our hospital because of multiple organ dysfunction and myocardial infarction. He had been complaining of vomiting, diarrhea and malaise for 3 days before admission. On examination his vital signs were stable. Laboratory data showed severe kidney and liver dysfunction as well as disseminated intravascular coagulation. Electrocardiography and echocardiography showed evidence of inferior and right ventricular myocardial infarction. Coronary angiography showed total occlusion of the proximal segment of the right coronary artery and 75% stenosis of the left main trunk. There were no symptoms or physical finding suggesting shock. After initiation of intra-aortic balloon pumping and continuous hemodiafiltration, his multiple organ dysfunction improved rapidly. He underwent coronary artery bypass grafting on the 7th hospital day and was discharged on the 39th hospital day. It was suggested that low cardiac output due to right ventricular infarction and left ventricular dysfunction dehydration gradually caused his multiple organ dysfunction in the absence of sign of cardiogenic shock. Clinicians should remember the potential for atypical presentation of cardiogenic shock, especially due to right ventricular dysfunction.
    Nihon Kyukyu Igakukai Zasshi 01/2014; 25(4):171-178. DOI:10.3893/jjaam.25.171
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    ABSTRACT: Various modalities have been employed effectively according to the tumor recurrence status in patients with hepatocellular carcinoma (HCC) undergoing hepatectomy. Therefore, their overall prognosis depends largely on the pattern of recurrence/treatment. We investigated the patterns of recurrence and prognosis in HCC patients, especially in relation to the hepatitis virus infection status. The study population comprised 244 patients with HCC undergoing hepatectomy. Curative treatments, including repeated hepatectomies, were performed for recurrences, whenever possible. Detailed information on recurrences was collected until the recurrences exceeded Milan's criteria. The 5-year disease-free survival, survival within the Milan criteria, and overall survival were 38.4 %, 56.3 %, and 74.5 %, respectively. In the comparison between patients with hepatitis C and B virus-related HCC (HC-HCC: n = 111; and HB-HCC: n = 45, respectively), the former showed lower disease-free (30.2 % vs. 40.7 % at 5 years, P = 0.061) and overall (65.7 % vs. 89.7 % at 5 years, P = 0.011) survivals; they also showed a higher incidence of multinodular (≥4) intrahepatic recurrences (19.4 % vs. 5.3 % at 3 years, P = 0.010). Whereas, the incidences of recurrences exceeding the Milan criteria because of other components were comparable. Patients with HC-HCC showed a higher incidence of intrahepatic recurrences characterized by multiple lesions and the difference became increasingly more pronounced with time. Patients with HC-HCC was associated with a higher carcinogenesis in the background liver than those with HB-HCC, and this difference was aggravated with time after hepatic resection. This article is protected by copyright. All rights reserved.
    Liver international: official journal of the International Association for the Study of the Liver 12/2013; 34(5). DOI:10.1111/liv.12447 · 4.41 Impact Factor
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    ABSTRACT: Subtotal stomach-preserving pancreatoduodenectomy (SSPPD), in which the pylorus ring is resected and most of the stomach is preserved, has been performed recently in Japan. This study was undertaken to clarify the incidence of delayed gastric emptying (DGE) after SSPPD at a high-volume hospital and to determine the independent factors that influence the development of DGE after SSPPD. Between 2002 and 2011, 201 consecutive patients underwent standardized SSPPD. After SSPPD, DGE (defined according to the International Study Group of Pancreatic Surgery) was analyzed, and associated variables were assessed by univariate and multivariate analyses, retrospectively. Clinically significant DGE (grades B and C) occurred in 35 (17 %) of the 201 patients; 26 patients had other accompanying abdominal complications (secondary DGE), and pancreatic leakage was the sole risk factor for DGE (odds ratio 6.63, 95 % CI 2.86-15.74; p < 0.001). Only nine (4 % of all patients) of the 35 patients with clinically significant DGE were classified as having DGE that had arisen without any obvious etiology (primary DGE). DGE after SSPPD is strongly linked to the occurrence of other postoperative intra-abdominal complications such as pancreatic fistula. The incidence rate of primary DGE after SSPPD was 4 %. Although the ISGPS classification of DGE is clearly applicable, the grades do not explain why DGE occurs. Primary and secondary DGE should therefore be defined separately.
    World Journal of Surgery 10/2013; 38(4). DOI:10.1007/s00268-013-2288-y · 2.35 Impact Factor
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    ABSTRACT: BACKGROUND: The fucosylated fraction of alpha-fetoprotein (AFP-L3) has been used as a diagnostic marker for hepatocellular carcinoma (HCC). Recently, a highly sensitive immunoassay using an on-chip electrokinetic reaction and separation by affinity electrophoresis (micro-total analysis system; μTAS) has been developed. AIM: The aim of this study was to investigate the relationship between changes in the serum AFP-L3 level measured by μTAS assay and recurrence of HCC after curative treatment. METHODS: A total of 414 HCC patients who met the Milan criteria and underwent hepatectomy or radiofrequency ablation were investigated prospectively for the relationship between HCC recurrence and values of tumor markers. RESULTS: There were significant differences in recurrence-free survival between groups with and without AFP-L3 elevation measured before and after treatment (p = 0.024 and p = 0.001 for before and after treatment, respectively). Multivariate analysis revealed that AFP-L3 status (p = 0.002) measured 1 month after treatment was a significant independent predictor of HCC recurrence after curative treatment. CONCLUSIONS: Elevation of the serum AFP-L3 level before treatment is a predictor of HCC recurrence, and sustained elevation of the AFP-L3 level after treatment is an indicator of HCC recurrence. Repeated measurement of μTAS AFP-L3 should be performed for surveillance of HCC recurrence after curative treatment.
    Digestive Diseases and Sciences 04/2013; 58(8). DOI:10.1007/s10620-013-2661-6 · 2.26 Impact Factor
  • Journal of Hepatology 04/2013; 58:S112. DOI:10.1016/S0168-8278(13)60266-4 · 10.40 Impact Factor
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    ABSTRACT: BACKGROUND: We assessed the benefit of hepatic and pulmonary resections in patients with liver and lung recurrences, respectively, after resection of esophageal carcinoma. METHODS: The study population consisted of 138 consecutive patients with recurrent esophageal carcinoma after esophagectomy conducted between 2003 and 2005. The pattern, timing of appearance, and the prognosis of these recurrences were investigated, paying particular attention to those undergoing hepatic and pulmonary resections. RESULTS: In total, 55 and 92 patients developed locoregional and distant-organ metastases 13 and 6 months (median) after surgery, respectively, including 9 patients with both types of recurrence. The distant-organ metastases were found in the liver (n = 26), lung (n = 27), bone (n = 21), and other organs (n = 29). Patients with pulmonary recurrences had a better overall prognosis (median survival after recurrence detection 13 months) than those with hepatic metastases (5 months) or nonhepatic nonpulmonary metastases. (3 months) Hepatic and pulmonary resections were carried out in patients with oligonodular (n = ≤ 2) isolated liver and lung metastases (n = 5, respectively). Although the survivals of patients with lung metastases who were treated/not treated by pulmonary resection were different (median survival: 48 vs. 10 months, p < 0.01), the difference in the survivals between patients with hepatic metastases who were treated/not treated by hepatic resection reached only borderline statistical significance (13 vs. 5 months, p = 0.06). CONCLUSIONS: Resection of pulmonary metastases yields a survival benefit in properly selected patients. The benefit of resection for hepatic metastases remains controversial.
    World Journal of Surgery 11/2012; 37(2). DOI:10.1007/s00268-012-1830-7 · 2.35 Impact Factor
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    ABSTRACT: We compared diagnostic ability for detecting hepatic metastases between gadolinium ethoxy benzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) on a 1.5-T system, and determined whether DWI is necessary in Gd-EOB-DTPA-enhanced MRI for diagnosing colorectal liver metastases. We assessed 29 consecutive prospectively enrolled patients with suspected metachronous colorectal liver metastases; all patients underwent surgery and had preoperative Gd-EOB-DTPA-enhanced MRI. Overall detection rate, sensitivity for detecting metastases and benign lesions, positive predictive value, and diagnostic accuracy (Az value) were compared among three image sets [unenhanced MRI (DWI set), Gd-EOB-DTPA-enhanced MRI excluding DWI (EOB set), and combined set]. Gd-EOB-DTPA-enhanced MRI yielded better overall detection rate (77.8-79.0 %) and sensitivity (87.1-89.4 %) for detecting metastases than the DWI set (55.9 % and 64.7 %, respectively) for one observer (P < 0.001). No statistically significant difference was seen between the EOB and combined sets, although several metastases were newly detected on additional DWI. Gd-EOB-DTPA-enhanced MRI yielded a better overall detection rate and higher sensitivity for detecting metastases compared with unenhanced MRI. Additional DWI may be able to reduce oversight of lesions in Gd-EOB-DTPA-enhanced 1.5-T MRI for detecting colorectal liver metastases.
    Japanese journal of radiology 07/2012; 30(8):648-58. DOI:10.1007/s11604-012-0105-4 · 0.73 Impact Factor
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    ABSTRACT: BACKGROUND: Intermittent clamping (IC) and ischemic preconditioning (PC) reportedly protect the liver against the ischemia/reperfusion (I/R) injury induced by inflow occlusion during hepatectomy. While IC cycles consisting of 15 min of clamping with 5 min of reperfusion are used empirically, the optimal IC cycle has not been established. We compared the effects of various cycles of IC and PC in the rat liver. METHODS: Rats subjected to 60 min of inflow occlusion were assigned to the following five groups (n = 8 each): 60 min of continuous ischemia; 4 cycles comprising 15 min of ischemia/5 min of reperfusion; 6 cycles comprising 10 min of ischemia/3.3 min of reperfusion; 12 cycles comprising 5 min of ischemia/1.7 min of reperfusion (the time ratio of ischemia to reperfusion in the IC groups was 3:1); and PC (10/10 min of ischemia/reperfusion) prior to 60 min of ischemia. The severity of liver injury was assessed by determining the serum alanine aminotransferase (ALT) level, bile flow, tissue glutathione content, and induction of apoptosis (terminal deoxynucleotidyl transferase-mediated biotin nick end-labeling [TUNEL] staining and DNA laddering), and by histological examination of areas of severe necrosis. RESULTS: All the parameters indicated that liver injury was attenuated in the three IC groups compared with the continuous group; furthermore, this effect became increasingly marked with shorter cycles of IC. PC did not exert a protective effect under the present experimental conditions. CONCLUSION: Various cycles of IC consistently conferred protection against I/R injury, and IC with shorter cycles of ischemia and reperfusion was more effective. No protective effect of PC was evident. IC is a more robust strategy than the PC protocol for liver protection.
    Journal of Gastroenterology 06/2012; 48(1). DOI:10.1007/s00535-012-0613-0 · 4.02 Impact Factor
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    ABSTRACT: Recently, the successful application of portal inflow modulation has led to renewed interest in the use of left lobe grafts in adult-to-adult living donor liver transplantation (LDLT). However, data on the hepatic hemodynamics supporting portal inflow modulation are limited, and the optimal portal circulation for a liver graft is still unclear. We analyzed 42 consecutive adult-to-adult left lobe LDLT cases without splenectomy or a portocaval shunt. The mean actual graft volume (GV)/recipient standard liver volume (SLV) ratio was 39.8% ± 5.7% (median = 38.9%, range = 26.1%-54.0%). The actual GV/SLV ratio was less than 40% in 24 of the 42 cases, and the actual graft-to-recipient weight ratio was less than 0.8% in 17 of the 42 recipients. The mean portal vein pressure (PVP) was 23.9 ± 7.6 mm Hg (median = 23.5 mm Hg, range = 9-38 mm Hg) before transplantation and 21.5 ± 3.6 mm Hg (median = 22 mm Hg, range = 14-27 mm Hg) after graft implantation. The mean portal pressure gradient (PVP - central venous pressure) was 14.5 ± 6.8 mm Hg (median = 13.5 mm Hg, range = 3-26 mm Hg) before transplantation and 12.4 ± 4.4 mm Hg (median = 13 mm Hg, range = 1-21 mm Hg) after graft implantation. The mean posttransplant portal vein flow was 301 ± 167 mL/minute/100 g of liver in the 38 recipients for whom it was measured. None of the recipients developed small-for-size syndrome, and all were discharged from the hospital despite portal hyperperfusion. The overall 1-, 3-, and 5-year patient and graft survival rates were 100%, 97%, and 91%, respectively. In conclusion, LDLT with a left liver graft without splenectomy or a portocaval shunt yields good long-term results for adult patients with a minimal donor burden.
    Liver Transplantation 03/2012; 18(3):305-14. DOI:10.1002/lt.22440 · 3.79 Impact Factor
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    ABSTRACT: The results of salvage hepatectomy for local recurrent hepatocellular carcinoma after incomplete percutaneous ablation therapy are still unclear. We conducted a retrospective analysis of 197 consecutive patients with hepatocellular carcinoma who underwent either salvage hepatectomy after prior incomplete percutaneous ablation therapy (salvage group; n=23) or primary hepatectomy as the initial treatment (primary group; n=174). The two groups were compared with respect to intraoperative data, operative mortality and morbidity, and long-term survival. The salvage group showed a significantly longer operation time (385 vs. 300 min; P=0.006) and a significantly greater intraoperative blood loss volume (402 vs. 265 ml; P=0.024). The postoperative mortality rate was zero in both groups, and the morbidity rates were similar. Although the 1-, 3-, and 5-year disease-free survival rates after hepatectomy were significantly worse in the salvage group than in the primary group (65%, 41%, and 33% vs. 81%, 51%, and 45%, respectively; P=0.031), the overall survival rates after hepatectomy did not differ significantly (91%, 91%, and 67% vs. 96%, 79%, and 65%, respectively; P=0.790). The 1-, 3-, and 5-year overall survival and disease-free survival rates after percutaneous ablation therapy were also not different from those in the primary group (100, 96, and 83%, P=0.115; and 96, 60, and 45%, P=0.524, respectively). The short-term and long-term results of salvage hepatectomy after incomplete percutaneous ablation therapy are equivalent to those of primary hepatectomy. Salvage hepatectomy is an acceptable treatment for patients with local recurrence of hepatocellular carcinoma after ablation therapy.
    Annals of Surgical Oncology 02/2012; 19(7):2238-45. DOI:10.1245/s10434-012-2220-y · 3.94 Impact Factor
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    ABSTRACT: To investigate the natural outcome and clinical implication of hypointense lesions in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI. Forty patients underwent Gd-EOB-DTPA-enhanced MRI for preoperative evaluation of HCC. Hypointense lesions in the hepatobiliary phase that were hypovascular 5mm of more were extracted for follow-up. We performed a longitudinal study retrospectively for these lesions regardless of whether classical HCC developed or emerged in a different area from that of the lesions being followed. Thirty one patients displayed 130 hypointense lesions on MRI and only nine showed no hypointense lesions. In total, 17 (13.1%) of 130 hypointense lesions on MRI developed into classical HCC. The cumulative rates for these lesions to develop into classical HCC were 3.2% at 1 year, 11.1% at 2 years and 15.9% at 3 years. The total occurrence rates of classical HCC (25.8% at 1 year, 52.6% at 2 years and 76.4% at 3 years) were higher compared to those regarding only occurrence of classical HCC from hypointense lesions on MRI (10.0% at 1 year, 35.6% at 2 years and 44.6% at 3 years), although no significant difference was observed (p=0.073). Hypointense lesions that are detected in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI have some malignant potential, although treating these lesions aggressively in patients who already have HCC may be too severe.
    European journal of radiology 01/2012; 81(11):2973-7. DOI:10.1016/j.ejrad.2012.01.007 · 2.65 Impact Factor
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    ABSTRACT: To compare the diagnostic performance of Gd-EOB-DTPA-enhanced MRI with that of triple phase 64-MDCT in the detection of hepatocellular carcinoma (HCC). Thirty-four patients with 52 surgically proven lesions underwent Gd-EOB-DTPA-enhanced MRI and triple phase 64-MDCT. Two observers independently evaluated MR and CT imaging on a lesion-by-lesion basis. Sensitivity, positive and negative predictive values and reproducibility were evaluated. The diagnostic accuracy of each modality was assessed with alternative-free response receiver operating characteristic (ROC) analysis. Both observers showed higher sensitivity in detecting lesions with MRI compared to CT, however, only the difference between the two imaging techniques for observer 2 was significant (P=0.034). For lesions 1cm or smaller, MRI and CT showed equal sensitivity (both 62.5%) with one observer, and MRI proved superior to CT with the other observer (MRI 75% vs. CT 56.3%), but the latter difference was not significant (P=0.083). The difference in positive and negative predictive value between the two imaging techniques for each observer was not significant (P>0.05). The areas under the ROC curve for each observer were 0.843 and 0.861 for MRI vs. 0.800 and 0.833 for CT and the differences were not significant. Reproducibility was higher using MRI for both observers, but the result was not significant (MRI 32/33 vs. CT 29/33, P=0.083). Gd-EOB-DTPA-enhanced MRI tended to show higher diagnostic accuracy, sensitivity and reproducibility compared to triple phase 64-MDCT in the detection of hepatocellular carcinoma, however statistical significance was not achieved.
    European journal of radiology 11/2011; 80(2):310-5. DOI:10.1016/j.ejrad.2010.07.026 · 2.65 Impact Factor
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    ABSTRACT: Intraoperative detection of new nodules is common in patients undergoing hepatectomy for colorectal liver metastases, although the value of intraoperative diagnosis is not well assessed. A prospectively collected and recorded database was retrospectively analyzed. Helical computed tomography (CT) results were correlated with those of the intraoperative diagnosis in 183 consecutive patients undergoing 254 consecutive hepatectomies, including repeated resection for colorectal liver metastases. In total, 270 nodules were newly detected during 65 hepatectomies. The sensitivity of CT to detect metastatic nodules was 72.8% (722/992), but it decreased to 34.6% (125/361) for small (≤ 1 cm diameter) tumors. Intraoperative visual inspection and/or palpation detected 207 of 270 nodules. Intraoperative ultrasonography (IOUS) played an important role in identifying deep (≥ 1 cm from the surface) and comparatively small (≤ 1 cm diameter) nodules (4/9 vs. 16/18, respectively, for those >1 cm vs. ≤ 1 cm diameter). The likelihood of intraoperative detection of new nodules increased from 10 in 112 to 6 in 9 when the preoperative tumor number increased from solitary to ≥ 10, resulting in an overall likelihood of 65 in 254 (25.6%). Of 65 patients with new nodules, 21 had at least one nodule that was detected only by IOUS. Preoperatively scheduled hepatectomy was altered in 47 (72%) patients, although additional limited resection(s) were sufficient to remove these nodules in 43 (91%) of them. Visual inspection, palpation, and IOUS had equally indispensable roles in detecting new nodules during hepatectomy. Detection was common and usually necessitated alteration, albeit moderately, of the surgical plan.
    World Journal of Surgery 09/2011; 35(12):2779-87. DOI:10.1007/s00268-011-1264-7 · 2.35 Impact Factor
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    ABSTRACT: We investigated the long-term profiles of liver regeneration after living-donor hepatectomy. Thirty-three donors participated in the study. Preoperative and postoperative liver volume was calculated using computed tomography. Volume assessment was repeated at 1 week, 2 weeks, 1 month, 3 months, 6 months, 12 months, and 4 years postoperatively. Donors were divided into the right (n = 23; residual liver volume, 42%) and left (n = 10; residual liver volume, 63%) groups according to the operative procedures. The restoration ratio to the preoperative liver volume (right vs. left groups) were 51%, 57%, 64%, 74%, 77%, 81%, and 88% vs. 69%, 72%, 76%, 79%, 83%, 84%, and 91% at 1 week, 2 weeks, 1 month, 3 months, 6 months, 12 months, and 4 years, respectively; the interindividual variation in the restoration ratio to the preoperative liver volume became narrower with time. Liver resection in humans resulted in rapid regeneration during the first 3 months, followed by a more moderate rate of regeneration thereafter, in proportion to the amount of liver mass resected. The volume of the regenerating liver appeared to converge towards the individual preoperative volume with time. However, the liver volume was not restored to the preoperative volume at 4 years after the resection.
    Journal of Gastrointestinal Surgery 06/2011; 15(9):1594-601. DOI:10.1007/s11605-011-1590-y · 2.36 Impact Factor
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    ABSTRACT: Noninvasive positive pressure ventilation (NPPV) has been suggested to be associated with adverse outcomes in emergency patients with acute respiratory failure (ARF), possibly because of a delay in tracheal intubation (TI). We hypothesized that protocol-based NPPV (pNPPV) might improve the outcomes, compared with individual physician-directed NPPV (iNPPV). To guide decision making regarding the use of NPPV, we developed an NPPV protocol. Observational data were collected before and after protocol implementation in consecutive patients with ARF and compared between the pNPPV and the iNPPV groups. The results for pNPPV (n = 37) were compared with those for iNPPV (n = 37). No significant baseline differences in patient characteristics were observed between the two groups except for mean age, which was higher in the pNPPV group than in the iNPPV group (P = 0.02). Rate of TI and duration of mechanical ventilation were similar in the two groups. However, the time from the start of NPPV until TI tended to be shorter in the pNPPV group than in the iNPPV group (P = 0.11). The hospital mortality rate was significantly lower in the pNPPV group than in the iNPPV group (P = 0.049). Although the length of hospital stay was shorter in the pNPPV group than in the iNPPV group, this trend did not reach statistical significance (P = 0.14). The present study suggests that pNPPV is effective and likely to improve the mortality rate of emergency patients with ARF.
    Journal of Anesthesia 02/2011; 25(1):42-9. DOI:10.1007/s00540-010-1051-x · 1.12 Impact Factor
  • International Heart Journal 01/2011; 52(4):197-202. DOI:10.1536/ihj.52.197 · 1.13 Impact Factor
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    ABSTRACT: The in-hospital mortality rate of acute myocardial infarction (AMI) is improving. In Japan, little information exists concerning the incidence and mortality of AMI. Therefore, our population-based analysis examined the incidence and mortality rate in AMI cases in individuals that lived in the Matsumoto region in 2002. We studied 169 AMI patients who were admitted within 14 days after a non-out-of-hospital cardiac arrest (non-OHCA group) and 63 patients with an AMI-related out-of-hospital cardiac arrest (OHCA group). The in-hospital mortality rate of the non-OHCA group was 9.5% (reperfusion therapy [+] 3.4%, [-] 22.7%, P < 0.0001). The rate of return of spontaneous circulation and the survival rate were 21% and 1.6%, respectively, in the OHCA group. The incidence of AMI in the non-OHCA and OHCA groups combined was 55.2 to 63.1 events/100,000 people annually and the mean age of AMI patients was 70 ± 13 years. The population-based mortality rate of AMI was 34% to 42%. The mortality rate of AMI remains high, and most deaths occur outside of the hospital. Prehospital care may lower the mortality rate of AMI.
    International Heart Journal 01/2011; 52(4):197-202. · 1.13 Impact Factor
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    ABSTRACT: Acute aortic dissection (AAD) classically presents as sudden, severe chest, back, or abdominal pain. However, there have been several documented cases presenting with atypical features. The clinical characteristics and outcomes of patients with painless AAD were investigated. The study group comprised 98 patients (53 males, 45 females; 66 ± 12 years) with AAD admitted to hospital from 2002 to 2007: 16 patients (17%) had no pain (painless group) and 82 patients had pain (painful group). In 81% of the painless group and 70% of the painful group there was a type A dissection. The painless group more frequently had a persistent disturbance of consciousness (44% vs. 6%, P < 0.001), syncope (25% vs. 1%, P < 0.001) and a focal neurologic deficit (19% vs. 2%, P = 0.006) as presenting symptoms. Imaging study findings were not significantly different. Cerebral ischemia (50% vs. 1%, P < 0.001) and cardiac tamponade (38% vs. 13%, P = 0.01) were more frequent complications in the painless group. In-hospital mortality was not significantly different (19% vs. 15%). However, the painless group had a more unfavorable functional outcome on overall performance category (P < 0.001). Painless AAD may be more frequent than previously reported. Painless AAD patients often present with a disturbance of consciousness or a neurologic deficit, and have a higher morbidity than painful AAD patients.
    Circulation Journal 12/2010; 75(1):59-66. DOI:10.1253/circj.CJ-10-0183 · 3.69 Impact Factor

Publication Stats

6k Citations
817.47 Total Impact Points


  • 2003–2013
    • Juntendo University
      • • Department of Hepatobiliary Pancreatic Surgery
      • • Faculty of Medicine
      Edo, Tōkyō, Japan
    • Teikyo University
      Edo, Tōkyō, Japan
  • 1999–2012
    • The University of Tokyo
      • Division of Surgery
      Tōkyō, Japan
  • 1996–2011
    • Shinshu University
      • • Division of Cardiovascular Medicine
      • • Department of Medicine
      • • Department of Internal Medicine I
      Shonai, Nagano, Japan
  • 2006
    • Showa General Hospital
      Edo, Tōkyō, Japan
  • 2002
    • Matsunami General Hospital
      Gihu, Gifu, Japan