他人の方が家族よりもCPRを用いた対応を行う確率が高い（RESS Abstract # 203）

日本人の家族は心停止に対し友人や同僚および他人よりも反応しにくい
Japanese family members were far less likely than friends, colleagues and strangers to effectively respond to a cardiac arrest
心停止した者に対し家族がCPRを行う頻度は、通りすがりの人や友人よりも低いとの日本人を対象としたスタディが2012年American Heart Association学会で発表された。2005～2009年に発生した心停止547,218件を再検討した結果、約140,000件は居合わせた者に目撃され医師の介入がないものであった。この居合わせた者には家族、友人および同僚、通りすがりの者などが含まれた。倒れてから救急隊を呼ぶまで、および救急隊を呼んでから到着するまでの時間は通りすがりの者が目撃した場合が最も短かった。家族はCPRを施行する確率が最も低く（36.5%）、電話で指示を受けようとする確率が最も高かった（45.8%）。電話での家族への指示は最も成功率が低く（39.4%）、家族は心臓マッサージのみを行うことが最も多かった（67.9%）。生存率や神経学的状態および心停止に対する反応は、家族が第一発見者であった場合に通りすがりの者と比較し最も低かった。この結果は日本における性差の大きさを示している、と筆者らは述べている。日本においては過去の研究で心停止を起こした者の妻や女性は全般的に男性に対しCPRを行う確率が低いことが示された。
Full Text

Family members didn't give CPR for cardiac arrests as often as passers-by or friends in a Japanese study presented at the American Heart Association's Scientific Sessions 2012.

In a review of 547,218 cardiac arrests occurring in 2005-09, researchers identified almost 140,000 incidents witnessed by bystanders without a physician's involvement. Bystander groups studied included family members, friends and colleagues, passers-by and others.

Researchers found:

  • The time interval between collapse and emergency call and between call and arrival to patients was shortest when witnessed by passers-by.
  • Family members were least likely (36.5 percent) to administer CPR, but most likely to receive telephone instructions from dispatchers (45.8 percent).
  • The telephone instruction to family members most frequently failed (39.4 percent) and family members most often used chest compressions only (67.9 percent).

"If you go into cardiac arrest in front of your family, you may not survive," said Hideo Inaba, M.D., Ph.D., lead author of the study and professor and chairman of the Department of Emergency Medical Science at Kanazawa University Graduate School of Medicine in Kanazawa, Japan. "Different strategies, including basic life support instruction targeting smaller households, especially those with 8 elderly residents, would improve survival, as would recruiting well-trained citizens willing to perform CPR on victims whose arrest was witnessed by family members."

CPR provided by family members may have been ineffective due to their lack of knowledge or fear of injuring their loved one, said Inaba. Cultural and demographic issues in Japan, which has a large gender gap, may also have contributed to the findings, he said.

In a study conducted in 2008, researchers found that Japanese women were less likely to attempt CPR. Men accounted for a majority of cardiac arrests in the current study, and their wives or daughters-in-law witnessed most of them, researchers said.

Japan has a rapidly aging population, with elderly people, mostly couples, in 42 percent of households in 2010, Inaba said.

"These characteristics of Japanese households might have contributed to our observations and may be different from households in the United States," Inaba said. "Also, the percentage of older persons in Japan is larger than in the U.S. population. So the results may be less applicable."

Furthermore, the database didn't include the exact location of each cardiac arrest, although basic life support response and outcomes differ between locations. The type of bystander who responds is also closely related to the location of the cardiac arrest.

Co-authors are: Takahisa Kamikura, M.D.; Tetsuo Maeda, M.D.; Yoshitaka Hamada, M.D., Ph.D.; Satoru Sakagami, M.D., PhD; and Taiki Nishi and Keiko Takase, master course students.

Author disclosures are on the abstract.