title: A case of the vacuum phenomenon as a mechanism of gas production in the abdominal wall.
abstract: A 40-year-old man experienced a collision with a car while driving a motorcycle in which the car was in the opposite lane and made a right turn. The patient was thrown approximately 10 m from the point of collision and, as he exhibited a consciousness disturbance, was transferred to our department. He had a score of 13 on the Glasgow Coma Scale with sinus tachycardia on arrival. He showed guarding of the abdomen. A pan scan disclosed traumatic subarachnoid hemorrhage, intraventricular hemorrhage, fractures of the atlas, thoracic spine, sternum and left femur, and gas in the abdomen located just in front of the stomach. As the gas in the abdomen was initially judged to be free air, the patient underwent emergency laparotomy. However, no signs of perforation or injury were detected throughout the entire digestive tract. The accumulation of minute gas (vacuum phenomenon) occurs as traumatic impact. As representative mimics of free air were not observed during surgery in the present case, we believe that the traumatic impact to the patient's abdomen as a result of the collision caused the accumulation of gas in the abdominal wall due to vacuum phenomenon. Physicians should be aware of this clinical entity to accurately recognize the mechanism of gas formation in patients showing negative laparotomy findings for gas in the abdomen. This unique case adds additional information regarding the documented etiologies of mimics of pneumoperitoneum.
authors.affiliation: Department of Acute Critical Care Medicine, Shizuoka Hospital, Juntendo University, Izunokuni City, Shizuoka, Japan; Department of Emergency and Critical Care Medicine, Nerima Hospital, Juntendo University, Nerima, Tokyo, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Mishima
authors.affiliation: Department of Acute Critical Care Medicine, Shizuoka Hospital, Juntendo University, Izunokuni City, Shizuoka, Japan; Department of Emergency and Critical Care Medicine, Nerima Hospital, Juntendo University, Nerima, Tokyo, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Omori
authors.affiliation: Department of Acute Critical Care Medicine, Shizuoka Hospital, Juntendo University, Izunokuni City, Shizuoka, Japan; Department of Emergency and Critical Care Medicine, Nerima Hospital, Juntendo University, Nerima, Tokyo, Japan.
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Ohsaka
authors.affiliation: Department of Acute Critical Care Medicine, Shizuoka Hospital, Juntendo University, Izunokuni City, Shizuoka, Japan; Department of Emergency and Critical Care Medicine, Nerima Hospital, Juntendo University, Nerima, Tokyo, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Takeda
authors.affiliation: Department of Acute Critical Care Medicine, Shizuoka Hospital, Juntendo University, Izunokuni City, Shizuoka, Japan; Department of Emergency and Critical Care Medicine, Nerima Hospital, Juntendo University, Nerima, Tokyo, Japan.
authors.forename: Kouhei
authors.initials: K
authors.lastname: Ishikawa
authors.affiliation: Department of Acute Critical Care Medicine, Shizuoka Hospital, Juntendo University, Izunokuni City, Shizuoka, Japan; Department of Emergency and Critical Care Medicine, Nerima Hospital, Juntendo University, Nerima, Tokyo, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Obinata
authors.affiliation: Department of Acute Critical Care Medicine, Shizuoka Hospital, Juntendo University, Izunokuni City, Shizuoka, Japan; Department of Emergency and Critical Care Medicine, Nerima Hospital, Juntendo University, Nerima, Tokyo, Japan.
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Oode
authors.affiliation: Department of Acute Critical Care Medicine, Shizuoka Hospital, Juntendo University, Izunokuni City, Shizuoka, Japan; Department of Emergency and Critical Care Medicine, Nerima Hospital, Juntendo University, Nerima, Tokyo, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Sugita
authors.affiliation: Department of Acute Critical Care Medicine, Shizuoka Hospital, Juntendo University, Izunokuni City, Shizuoka, Japan; Department of Emergency and Critical Care Medicine, Nerima Hospital, Juntendo University, Nerima, Tokyo, Japan. Electronic address: yyanaga@juntendo.ac.jp.
authors.forename: Youichi
authors.initials: Y
authors.lastname: Yanagawa
mesh_terms: D000007:Abdominal Injuries / Q000601:surgery*; D000063:Accidents, Traffic; D000328:Adult; D005740:Gases; D006801:Humans; D008297:Male; D009104:Multiple Trauma; D011027:Pneumoperitoneum / Q000601:surgery*; D014618:Vacuum
chemical_list: D005740:Gases