Table 1 (abstract A18). See text for description

Kulkarni AP, 2015 Ind J CCM

88 ICU patients in shock (all in MV)

Supine; IVC measured at the entry of hepatic vein

Single center, 175 views; 2 operators with prior IVC workshops, 2-year experience in bedside ultrasound.

Feasibility N/R (included only if both views available)

Min: 1.7 mm; [-3.7 to 4.0]

Max: 0.27 mm; [-3.6 to 4.0]

Distensibility 0.5%; [-16% to 17%]

Authors averaged the values obtained by two operators but did not report correlation.

Valette X,

2020

Echocardiography

131 ICU patients: 88 (67%) on MV (32 on pressure support, 56 in controlled mode), 5 (4%) on NIV]

Semi-recumbent; IVC measured 3 cm from the ICAJ

Two centers, 131 views; 2 operators advanced CCE training

Feasibility 2D: 94% in SC, 93% in TH.

Feasibility M-Mode: 83% in SC, 81% in TH.

No views at all in 0.015% (n=2)*

End Insp -0.1 mm; [-8.7 to 8.5]

End Exp 0.1 mm; [-7.5 to 7.7]

Resp. change 0.2 mm; [-5.3 to 5.8]

Collapsibility 2% [-39% to 42%]

Distensibility -0.5% [-21.5% to 20.6%]

Pearson correlation between SC and TH

-2D: End Exp 0.73; End Insp 0.84; Resp. change 0.86

- M-Mode: End Exp: 0.72; End Insp: 0.81; Resp. change 0.86

Moreno Garijo J, 2017

J Cardiothor Vasc Anaesth

40 CABG patients (all self-breathing)

Supine; IVC measured 3 cm from the ICAJ

Single center, 80 views; single operator with level II training in trans-thoracic echocardiography and advanced perioperative trans-esophageal echocardiography.

Feasibility: N/R

Collapsibility 2.4% [-27.6% to 34.5%]

Pearson correlation between SC and TH

Max 0.46; Min 0.55; Collapsibility 0.70

ICC intra-observer

-SC 0.98 Max, 0.98 Min, 0.95 Collapsibility

-TH 0.99 Max, 0.99 Min, 0.97 Collapsibility

ICC inter-observer**

-SC 0.95 Max, 0.98 Min, 0.96 Collapsibility

-TH 0.97 Max, 0.99 Min, 0.93 Collapsibility

Saul T,

2012

J Emerg Med

14 Volunteers (self-breathing)

Supine; IVC measured 2 cm from the ICAJ

Single center, 141 SC sagittal, 138 TH, 138 SC axial; 3 operators, IVC workshop, ultrasound fellowship completed.

Feasibility 100%

Mean measurements are mostly overlapping with differences below 1 mm.

Inter-observer Person correlation**

-SC sagittal 0.68 (average insp-exp)

-TH coronal 0.69 (average insp-exp)

- SC axial 0.72 (average insp-exp)

Shah R,

2018

Chest

110 patients (wards/ICU, ED) (self-breathing)

Supine; IVC measured 2-4 cm from the ICAJ

Single center, 284 views; 3 operators with usual ultrasound training.

Feasibility: SC 90%; TH 88%; SC axial 80%.

No views at all in 8.1% (n=9)

Overall mean measurements shows IVC size significantly higher in TH view. Similar results in the subgroup analysis according to FR.

Concordance on FR between SC and TH in 66% (sensitivity 62%, specificity 67%). Collapsibility ≥42% in TH showed good predictive value for FR (92%), but values <42% have low predictive value for being non-FR (23%).

Finnerty NM,

2017

Western J Emerg Med

39 Volunteers (self-breathing)

Supine; IVC measured 2-3 cm from the ICAJ

Single center, 351 views (117x3: SC sagittal, TH, SC axial); 3 operators experienced in IVC ultrasound (>150 scans), holding ultrasound certificates. Feasibility N/R

Mean measurements are mostly overlapping with differences <1 mm for IVC max and <2 mm for IVC min

ICC Inter-observer

-SC 2D: 0.86; M-Mode: 0.78 Max, 0.57 Min, 0.14 Collapsibility

-TH 2D: 0.74, M-Mode: 0.68 Max, 0.66 Min, 0.32 Collapsibility

Yao B,

2019

Shock

67 ICU patients (all MV)

Not specified; IVC measured 2-3 cm from the ICAJ

Single center, 201 views (SC sagittal, TH, SC axial); number of operators and their training not specified

Feasibility: SC 84%, TH 100%

-

Similar Area under Curve for predicting FR between SC (0.70) and TH (0.69). Higher Area under Curve for IVC diameter ratio (SC axial), 0.83