Key Statistical Figures

These statistics are also embedded in the relevant main-text sections.

Diastolic function / LVDD

  • 2025 ASE Step 1 e′ thresholds: septal less than or equal to 6 cm/s, lateral less than or equal to 7 cm/s, average less than or equal to 6.5 cm/s.

  • 2025 ASE Step 2 markers: average E/e′ greater than 14, LARS less than or equal to 18%, E/A less than or equal to 0.8 or greater than or equal to 2, LAVI greater than 34 mL/m².

  • LVDD present if reduced e′ plus at least one Step 2 marker, or preserved e′ plus at least two Step 2 markers.

  • BNP approximately 35 pg/mL and NT-proBNP approximately 125 pg/mL may help exclude acute volume overload in appropriate contexts.

Fluid responsiveness

  • IVC collapsibility: approximately 40–41% or greater suggests fluid responsiveness; specificity approximately 80–97%.

  • IVC Dmin-based distensibility: commonly 15% or greater; validation range approximately 12–21%; 18% in selected septic shock protocols; specificity approximately 85%.

  • IVC mean-based variability: 12%.

  • PLR positive response: 10–15% or greater increase in stroke volume, cardiac output, or LVOT VTI.

  • LVOT peak velocity respiratory variation: sensitivity approximately 79% in mechanical ventilation circulatory failure.

  • SVC collapsibility greater than 39%: specificity approximately 84% in mechanical ventilation circulatory failure.

  • Portal venous pulsatility fraction greater than 50%: commonly used abnormal threshold.

EPSS

  • EPSS less than 5.5 mm: sensitivity approximately 95%, negative likelihood ratio approximately 0.09 for LVEF less than 50%; negative likelihood ratio approximately 0.11 for LVEF less than 40%.

  • EPSS 11.5 mm or greater: positive likelihood ratio approximately 12, specificity 95% for LVEF less than 50%.

  • EPSS 13.5 mm or greater: positive likelihood ratio approximately 11, specificity 95% for LVEF less than 40%.

  • EPSS greater than 7 mm for LVEF less than 30%: sensitivity 100%, specificity 51.6%, negative likelihood ratio 0.00 in McKaigney cohort.

  • EPSS greater than 8 mm for LVEF less than 55%: sensitivity 83.3%, specificity 50% in McKaigney cohort.

Cardiac POCUS performance

  • Trained echocardiographers performing POCUS for LV abnormalities: sensitivity 85–89%, specificity 91–98% in meta-analysis of 33 studies with more than 6000 participants.

  • Inexperienced users versus experienced users: approximately 60–80% reduction in sensitivity.

  • AI-guided nurse POCUS, Narang et al.: greater than 98% high diagnostic quality for LV size/function and pericardial effusion; greater than 92% RV size/position; 58% IVC adequate.

  • Home POCUS, N = 15: 100% moderate comfort; 100% adequate qualitative LV function; 43% adequate quantitative assessment.

  • POCUS image quality in MET study: good approximately 39%, moderate approximately 42%, poor approximately 19%.

  • POCUS in MET deployment: correct diagnosis approximately 51% without POCUS versus approximately 78% with POCUS.

Tamponade

  • Pericardial effusion 10 mm or greater: often at least moderate or operationally significant in POCUS.

  • Respiratory transvalvular variation greater than 25%: suggests tamponade physiology in spontaneous breathing; less validated under positive-pressure ventilation.

  • RA collapse greater than one-third of cardiac cycle: highly specific for tamponade.

  • IVC greater than 2.1 cm with collapse less than 50%: formal elevated-RAP criterion.

  • IVC greater than 3.5 cm: not a universal formal RAP cutoff.

Lung POCUS

  • BLUE overall correct diagnosis in acute respiratory failure: approximately 90.5%.

  • Asthma/COPD: sensitivity 89%, specificity 97%.

  • Pulmonary oedema: sensitivity 97%, specificity 95%.

  • PE profile with DVT: sensitivity 81%, specificity 99%.

  • Pneumothorax with lung point: sensitivity 81%, specificity 100%.

  • Pneumonia: sensitivity 89%, specificity 94%.

  • Pleural effusion quad/sinusoid signs: sensitivity approximately 93%, specificity approximately 97%.

  • B-profile BLUE for acute pulmonary oedema: sensitivity approximately 97%, specificity approximately 95%.

  • A + DVT BLUE for PE: sensitivity approximately 81%, specificity approximately 99%.

Aortic POCUS

  • AAA detection sensitivity: 94–100%.

  • AAA negative predictive value: 98.6–100%.

  • EM ultrasound versus CT for AAA: within approximately 4.4 mm.

  • Stanford type A dissection sensitivity in one ED POCUS protocol: 100%.

  • Stanford type B dissection sensitivity in one ED POCUS protocol: 93.7%.

  • POCUS-first approach for type A dissection: mean time reduction approximately 146 minutes.

  • Acute aortic occlusion: most cases infrarenal; mean diagnostic delay in one series approximately 24 hours; morbidity/mortality 21–74%.

Obstetric/gynaecologic POCUS

  • IUP visualization: sensitivity 97%, specificity 71%, negative predictive value 99.96%.

  • POCUS with IUP visualization: mean length-of-stay reduction approximately 73.8 minutes.

  • Transvaginal placenta praevia assessment: PPV 99%, NPV 98%, false-negative rate 2.3%.

  • Ectopic pregnancy: sensitivity 90%, specificity 98%.

  • Uterine fibroids greater than 2 cm: sensitivity 84%, specificity 96%.

  • Adnexal masses greater than 3 cm: sensitivity 88%, specificity 95%.

  • Small intrauterine lesions less than 2 cm: sensitivity 40%, specificity 98%.

  • Mean time to diagnosis: POCUS 12 ± 5 minutes versus formal ultrasound 95 ± 30 minutes.

Airway POCUS

  • ED intubation complication rate: up to 12%.

  • Failed intubation: approximately 1 in 50 to 1 in 100.

  • Unanticipated difficult airways: greater than 90% in some studies.

  • Ultrasound improves cricothyrotomy success in cadaveric models with poorly defined neck anatomy.

  • Laryngeal air column width difference has been evaluated for post-extubation stridor prediction.

TCD

  • TCD interobserver agreement in cardiac arrest: Cohen’s kappa approximately 0.63 in one study; variable.

  • MCA/ICA ratio greater than 4–6: suggests moderate/severe vasospasm, study-specific.

  • MCA/BA ratio greater than 6: suggests severe vasospasm in some settings.

  • BHRI: greater than 30–35% preserved; 20–35% borderline; less than 10–20% severely impaired, center-specific.

Dengue

  • GBWT associated with severe dengue: odds ratio 2.35, 95% CI 1.88–2.82; sensitivity approximately 88%, specificity approximately 63%.

PH

  • TRV greater than 3.4 m/s: strongly suggests pulmonary hypertension.

  • Formal PH: mean PAP greater than 20 mmHg in current criteria, or greater than 25 mmHg in older criteria.