Details of a Researcher - Yamanaka, Takahiro

Optimal route of supplementary protein delivery for physical recovery in critically ill patients: Protocol for a multicenter randomized clinical trial

Yoshida M., Yamamoto R., Sagawa M., Toshima G., Ukita S., Higashibeppu N., Tatsumi H., Matsuo Y., Yoneda R., Ishihara E., Ogawa H., Kuronuma N., Yoshida T., Tampo A., Ishii K., Katsura Y., Inoue K., Takatani Y., Suzuki T., Tampo A., Araki S., Minoura A., Suzuki G., Morinaga K., Kaku M., Suganuma S., Yamanaka T., Ota Y., Ookawa R., Iino M., Nakamura K.

Clinical Nutrition Espen 73 2026.06

　View Summary

Background and aims Approximately 50% of critically ill patients develop physical impairment following intensive care. To overcome this impairment, major international guidelines for nutrition therapy recommend a higher protein intake than the standard dose. However, the optimal delivery route of additional protein supplementation to achieve protein target intake remains unclear. Therefore, this trial aims to identify the optimal route for supplementary protein delivery, either enteral nutrition (EN) alone or EN combined with parenteral amino acid supplementation, on physical outcomes. Methods This is a nationwide multicenter open-label randomized parallel-group trial. This study will encompass adult patients admitted to intensive care units in which EN can be initiated within 48 h of admission. Participants will be assigned to either the EN-only group (all protein provided enterally using high-protein EN formulas) or the EN + PN group (protein provided via EN combined with supplementary intravenous amino acids using standard-protein EN formulas) to achieve the target dose. The nutritional targets are 20–30 kcal/kg/day for energy and 1.5–1.8 g/kg/day for protein within 3–5 days post-EN initiation. The primary outcome is functional independence, defined as a Barthel Index score of ≥ 85, at 90 days following randomization. Ethics and dissemination The Ethics Committee of Keio University School of Medicine approved this study (approval number: 20251054). Written informed consent will be obtained from all participants or their legal representatives. Trial registration This protocol was registered at the University Hospital Medical Information Network Clinical Trials Registry on July 12, 2025 (UMIN000058441: https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000066822 )
- Access to Document (DOI)
Potential return of spontaneous circulation in Japanese out-of-hospital cardiac arrest patients with pseudo–pulseless electrical activity: a post hoc analysis of a prospective multicentric study

Horikoshi Y., Hamaguchi J., Ishizawa R., Yamanaka T., Shimizu K., Kitamura N., Homma Y., Funakoshi H., Tagami T., Yasunaga H., Takeda M., Aso S., Yamanaka T., Shimizu K., Kitamura N., Funakoshi H., Yasunaga H., Aso S.

Resuscitation Plus 29 2026.05

　View Summary

Introduction As of yet, there are few studies of Asian patients with pseudo-pulseless electrical activity (PEA). Japanese patients with out-of-hospital cardiac arrest (OHCA) tend to be elderly, experience cardiac arrest while at home, and present with severe illness. The present study evaluated the prognostic implications of pseudo-PEA in a Japanese cohort with a high risk of OHCA. Methods The present study is a post hoc analysis of SOS-KANTO 2017, a prospective, multicentric study which included OHCA patients with PEA on hospital arrival who underwent echocardiographic assessment during resuscitation. The patients were categorized into a pseudo-PEA and a true PEA group. The primary outcome was the return of spontaneous circulation (ROSC). The secondary outcomes included survival to hospital admission, 30-day survival, and a favorable neurological status at discharge. Logistic regression was performed with cardiac activity as the primary predictor after adjusting for covariates. Results Of 894 eligible patients, 345 had pseudo-PEA, and 549 had true PEA. In total, 49.3% achieved ROSC. The pseudo-PEA group had a significantly higher rate of ROSC (87.2% vs. 25.5%; p < 0.01). On multivariable logistic regression, the pseudo-PEA group was independently associated with a high ROSC rate (odds ratio [OR]: 22.1; 95% confidence interval [CI]: 14.2–34.3), survival to hospital admission (OR: 17.8; 95% CI: 11.2–28.2), 30-day survival (OR: 51.9; 95% CI: 7.33–367), and favorable neurological outcome at discharge (OR: 14.3; 95% CI: 1.62–125). Conclusion Pseudo-PEA may be associated with a higher rate of ROSC and favorable, short and middle-term outcomes in Japanese patients with OHCA. Early echocardiographic assessment of cardiac activity may help prognostication and guide resuscitation even in high-risk populations.
- Access to Document (DOI)
Hydrogen Molecule Delivery System to Ischemic Intestine Using Resuscitative Endovascular Balloon Occlusion of Aorta in Hemorrhagic Shock—A Proof-of-Concept Study

Yamanaka T., Matsuoka T., Homma K., Tamura T., Suzuki S., Suzuki S., Kaito D., Yoshizawa J., Yajima K., Ono S., Maeshima K., Kobayashi E., Sano M., Sasaki J.

Biomedicines 14 ( 2 ) 2026.02

　View Summary

Background: The use of resuscitative endovascular balloon occlusion of the aorta (REBOA) for hemorrhagic shock in the torso has become increasingly common as a bridge to definitive hemostasis. Hydrogen molecules, distributed throughout the bloodstream, alleviate ischemic injury but cannot reach ischemic organs during REBOA use. This study investigates whether intra-aortic irrigation with hydrogen-dissolved saline under REBOA use delivers hydrogen to the intestine in a swine hemorrhagic shock model. Methods: We induced volume-regulated hemorrhagic shock in a 40 kg female swine. Following this, hydrogen-dissolved saline irrigation was initiated through an intra-aortic catheter positioned distal to the REBOA balloon. Hydrogen concentration in the portal vein was determined in four models: controlled hemorrhagic shock with full REBOA inflation during the standard occlusion time, uncontrolled hemorrhagic shock with liver injury and full REBOA inflation during the extended occlusion time, uncontrolled hemorrhagic shock with liver injury and partial REBOA inflation during the extended occlusion time, and as the control model, controlled hemorrhagic shock with full REBOA inflation during the standard occlusion time with normal saline irrigation without hydrogen. Results: Hydrogen concentration in the portal vein was found to be 0.224 mg/L (13.998%) in the controlled hemorrhagic shock model with full REBOA inflation, 0.049 mg/L (3.063%) in the uncontrolled hemorrhagic shock model with liver injury and full REBOA inflation, 0.018 mg/L (1.125%) in the uncontrolled hemorrhagic shock model with liver injury and partial REBOA inflation, and 0.002 mg/L (0.015%) in the control model. These results demonstrate the presence of hydrogen in the portal vein under different REBOA applications. Conclusions: Increased hydrogen concentration in the portal vein indicated that hydrogen was delivered to the intestine. These findings suggest an approach for drug administration during REBOA use. However, further investigations are required to establish its application in clinical settings.
- Access to Document (DOI)
Bacterial contamination of ultrasound probes in emergency departments: a multi-centre observational study

Yamanaka T., Yamamoto R., Yajima K., Yamashita I., Kurihara T., Kujirai D., Moritani K., Kamikura H., Koh H., Sasaki J.

Journal of Hospital Infection 163 23 - 29 2025.09

ISSN 01956701

　View Summary

Background: Ultrasound is frequently used in emergency departments (EDs) for patient evaluation and diagnosis. Despite the risk of probe contamination from body fluids and blood, the rate of such contamination remains unclear. Aim: This study aimed to evaluate bacterial contamination of ultrasound probes in EDs, focusing on hospital types and reprocessing methods. Methods: A multi-centre prospective observational study was conducted at a university hospital, a non-academic tertiary hospital, and a regional hospital in 2023. Samples were collected from probes used on ED patients. Reprocessing methods included water-moistened wipes alone, water-moistened wipes with ethanol wipes, quaternary ammonium wipes alone, and quaternary ammonium wipes with ethanol or hypochlorite wipes. Outcomes included the level of bacterial contamination, measured by colony-forming units (cfu) per total surface area of each probe, and resistant bacterial strains. Findings: The median cfu was 10 (IQR: 0–50) at the university hospital, 40 (10–135) at the non-academic tertiary hospital, and 30 (1–95) at the regional hospital. By reprocessing method, the median cfu was 20 (1–90) for water-moistened wipes alone, 10 (0–20) for water-moistened wipes and additional ethanol wipe, 90 (40–180) for quaternary ammonium wipes alone, and 20 (1–50) for quaternary ammonium wipe and additional ethanol or hypochlorite wipe. Resistant bacterial strains were found on 18.2% of probes. Conclusion: High levels of bacterial contamination, including resistant strains, were observed on ultrasound probes in EDs, regardless of facility type and reprocessing method.
- Access to Document (DOI)
Characteristics of burn injuries in old and extremely old patients: A city-wide study

Yamanaka T., Yamamoto R., Sasaki J.

Burns Open 11 2025.07

　View Summary

Background: The global population is aging rapidly. However, research on the characteristics of burn injuries in extremely old individuals remains limited. The current study aimed to identify the characteristics of burn injuries among elderly people by examining a city-wide burn database in Tokyo. Methods: This observational study was conducted at 14 burn centers, and data from the Tokyo Burn Unit Association registry from 1999 to 2020 were used. Demographic characteristics, burn mechanisms and severity, and clinical outcomes were compared among three age groups: >80 (very old), 65–79 (old), and 18–64 years. Results: In total, 11,876 patients with burn, including 1,150 aged > 80 years, 1,916 aged 65–79 years, and 8,810 aged 18–64 years, were analyzed. Older patients had a higher incidence of flame burns, burns in the closed space, and trunk, perineum, and lower extremity injuries. The older population had a greater injury severity, longer length of hospital stay, and higher in-hospital mortality rate. Similar trends were observed in the very old population. Conclusion: This study elucidated the characteristics of burn injuries, which included injury mechanisms and anatomical burn sites, among elderly individuals.
- Access to Document (DOI)

display all >>

Page Top ▲

Memberships in Academic Societies 【 Display / hide 】

日本心肺補助学会,

2024

-

Present
日本救急医学会,

2019

-

Present
日本熱傷学会,

2019

-

Present
日本集中治療医学会,

2019

-

Present

Page Top ▲

KEIO RESEARCHERS INFORMATION SYSTEM

Career 【 Display / hide 】

Career 【 Display / hide 】

Academic Background 【 Display / hide 】

Academic Background 【 Display / hide 】

Licenses and Qualifications 【 Display / hide 】

Licenses and Qualifications 【 Display / hide 】

Research Areas 【 Display / hide 】

Research Areas 【 Display / hide 】

Papers 【 Display / hide 】

Papers 【 Display / hide 】

Memberships in Academic Societies 【 Display / hide 】

Memberships in Academic Societies 【 Display / hide 】