title: The role of inferior vena cava diameter in volume status monitoring; the best sonographic measurement method?
abstract: OBJECTIVE
  This study aims to determine the site of and the best sonographic method for measurement of inferior vena cava (IVC) diameter in volume status monitoring.
  
  
  METHODS
  This observational before-and-after study was performed at the intensive care unit of the emergency department. It included hypotensive adult patients with suspected sepsis who were recommended to receive at least 20 mg/kg fluid replacement by the emergency physician. The patients were fluid replaced at a rate of 1000 mL/h, and maximum and minimum IVC diameters were measured and the Caval index calculated sonographically via both B-mode and M-mode. Hence, IVC's volume response was assessed by a total of 6 parameters, 3 each in M-mode and B-mode. Freidman test was used to assess the change in IVC diameter with fluid replacement. Wilcoxon test with Bonferroni correction was used to determine which measurement method more sensitively measured IVC diameter change.
  
  
  RESULTS
  Twenty-eight patients with a mean age of 71.3 were included in the final analysis.The IVC diameter change was significant with all 6 methods (P < .001). The IVC minimum diameter change measured on M-mode during inspiration (M-mode i) was the only measurement method that significantly showed diameter change with each 500-mL fluid replacements. The initial and the subsequent M-mode i values after each 500 mL of fluid were 5.65 ± 3.34; 8.05 ± 3.66; 10.16 ± 3.61, and 11.21 ± 2.94, respectively (P < .001, P < .002, and P < .003, respectively).
  
  
  CONCLUSIONS
  Inferior vena cava diameter was changed by fluid administration. The M-mode i method that most sensitively measures that change may be the most successful method in volume status monitoring.
authors.affiliation: Beykoz State Hospital, Istanbul, Turkey.
authors.forename: Nalan Gökçe
authors.initials: NG
authors.lastname: Çelebi Yamanoğlu
authors.affiliation: Haseki Training and Research Hospital, Istanbul, Turkey. Electronic address: adnanyaman29@gmail.com.
authors.forename: Adnan
authors.initials: A
authors.lastname: Yamanoğlu
authors.affiliation: İzmir Bozyaka Training and Research Hospital, Izmir, Turkey.
authors.forename: İsmet
authors.initials: İ
authors.lastname: Parlak
authors.affiliation: İzmir Bozyaka Training and Research Hospital, Izmir, Turkey.
authors.forename: Pelin
authors.initials: P
authors.lastname: Pınar
authors.affiliation: Mehmet Akif Ersoy Training and Research Hospital, Şanlıurfa, Turkey.
authors.forename: Ali
authors.initials: A
authors.lastname: Tosun
authors.affiliation: İzmir Bozyaka Training and Research Hospital, Izmir, Turkey.
authors.forename: Burak
authors.initials: B
authors.lastname: Erkuran
authors.affiliation: İzmir Bozyaka Training and Research Hospital, Izmir, Turkey.
authors.forename: Gizem
authors.initials: G
authors.lastname: Aydınok
authors.affiliation: Marmara University, Istanbul, Turkey.
authors.forename: Fatih
authors.initials: F
authors.lastname: Torlak
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004636:Emergency Service, Hospital; D005260:Female; D005440:Fluid Therapy; D006801:Humans; D007022:Hypotension / Q000000981:diagnostic imaging* / Q000209:etiology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D011446:Prospective Studies; D018805:Sepsis / Q000150:complications; D014463:Ultrasonography; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging*; D014883:Water-Electrolyte Imbalance / Q000000981:diagnostic imaging* / Q000209:etiology / Q000628:therapy