title: Characteristics of high-echoic objects in the hepatic vessels of patients with cardiopulmonary arrest: a prospective cohort study.
abstract: BACKGROUND
  High-echoic objects in the hepatic vessels of patients with cardiopulmonary arrest (CPA) are frequently detected by ultrasonography.
  
  
  OBJECTIVE
  To demonstrate this phenomenon and clarify its clinical characteristics.
  
  
  METHODS
  In a tertiary care academic medical centre, 203 CPA patients were evaluated by ultrasonography. CT determined the origin and location of high-echoic objects detected in the liver. The frequency and characteristics of this phenomenon were investigated. The background, laboratory data and survival rate were compared between patients with and without high-echoic objects.
  
  
  RESULTS
  High-echoic objects were seen in 73 (36.0%) patients and could clearly be detected in the hepatic veins of 41 (56.2%) patients. CT confirmed that these were gas in 27 of 53 patients, and were clearly visible in the hepatic veins in 12 (44.4%) patients. Hepatic portal venous gas was not identified. Compared to patients without high-echoic objects, witnessed arrest (p<0.001), bystander cardiopulmonary resuscitation (p=0.005), ventricular fibrillation or pulseless electrical activity (p=0.012) and return of spontaneous circulation (p=0.018) were significantly less frequent in patients with high-echoic objects. These patients had a lower incidence of survival to discharge (1.4% vs 7.7%, p=0.100). Multivariate analysis showed that absence of high-echoic objects was a marginally significant factor in association with return of spontaneous circulation (p=0.052).
  
  
  CONCLUSIONS
  High-echoic objects were often observed on ultrasonography in CPA patients; these objects were considered hepatic venous gas. The presence of high-echoic objects may be a poor prognostic sign in patients with CPA.
authors: Critical Care and Emergency Centre, Yokohama City University School of Medicine, 4-57 Urafune-cho, Minami-ku, Yokohama 232-0024, Japan. s_arata@yokohama-cu.ac.jp
authors: Shinju
authors: S
authors: Arata
authors: Junichi
authors: J
authors: Suzuki
authors: Yoshihiro
authors: Y
authors: Moriwaki
authors: Noriyuki
authors: N
authors: Suzuki
authors: Masayuki
authors: M
authors: Iwashita
authors: Mitsugi
authors: M
authors: Sugiyama
authors: Satoshi
authors: S
authors: Morita
mesh_terms: D000368:Aged; D005260:Female; D005740:Gases / Q000032:analysis; D006323:Heart Arrest / Q000000981:diagnostic imaging* / Q000401:mortality; D006503:Hepatic Veins / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011446:Prospective Studies; D015996:Survival Rate; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography
chemical_list: D005740:Gases