Bedside Ultrasound Detects Portal Venous Gas in Severe Abdominal Emergencies: A Case Series

Breaking: Bedside ultrasound uncovers portal venous gas in severe abdominal disease, new case series signals crucial diagnostic potential

In a striking growth for emergency care, clinicians using point‑of‑care ultrasound (POCUS) have identified portal venous gas in patients with severe abdominal illness. A recent case series highlights this bedside finding as a potential early clue that could accelerate diagnosis and management when time is critical.

Portal venous gas (PVG) refers to gas within the portal venous system, a finding historically linked to serious intra‑abdominal conditions. While PVG can arise from various processes, including inflammatory or infectious states, bowel ischemia remains among the most concerning causes. The new report underscores how a rapid ultrasound exam at the patient’s side can reveal PVG before more extensive imaging is available.

Experts caution that PVG is not a standalone diagnosis. Rather, it serves as an critically importent sign that clinicians should integrate with the patient’s history, exam, laboratory results, and imaging. When PVG appears on ultrasound, it may prompt expedited patient reassessment, earlier surgical or interventional consultation, and timely initiation of supportive care. Simultaneously occurring, not every PVG finding necessitates surgery; careful clinical judgment remains essential.

Why this matters now

The ability to detect PVG at the bedside offers several potential advantages.First, it can shorten the interval between presenting symptoms and critical decision‑making. Second, it reinforces the value of POCUS as a first‑line tool in acute abdomen scenarios, where rapid triage can influence outcomes. Third, it may help identify high‑risk patients who require urgent CT confirmation or surgical evaluation, while sparing others from unnecessary delays in care.

Clinicians adopting this approach should be mindful of the limitations. PVG is a sign,not a diagnosis,and ultrasound findings can be operator dependent. Ultrasound should complement, not replace, confirmatory imaging and clinical correlation.Training, standard protocols, and ongoing quality assurance are key to maximizing safety and effectiveness in real‑world settings.

Key facts at a glance

Aspect	Summary
What PVG is	Gas within the portal venous system detected by imaging, often associated with serious abdominal pathology.
POCUS role	Bedside ultrasound can rapidly identify PVG, aiding immediate assessment and triage decisions.
Clinical significance	PVG signals possible severe disease such as bowel ischemia; requires correlation with clinical context and further imaging.
Management pathway	Prompt re‑evaluation, escalation to specialist teams, and consideration of urgent imaging or intervention as indicated.
Limitations	Not a definitive diagnosis; ultrasound findings depend on operator skill and patient factors; CT remains a key reference tool.

What this means for clinicians and patients

For emergency departments and urgent care settings, the ability to spot PVG with POCUS adds a potentially life‑saving dimension to initial evaluation. Training programs that emphasize standardized PVG assessment can definitely help clinicians interpret findings accurately and act swiftly when necessary. Parallel efforts to improve access to CT when indicated will support sound clinical decisions and reduce diagnostic delays in the most time‑sensitive cases.

Evergreen insights for ongoing practice

As ultrasound devices become more ubiquitous, integrating PVG detection into routine abdominal assessments could become a standard component of the bedside workflow.key long‑term takeaways include investing in hands‑on ultrasound training, developing clear escalation protocols, and maintaining rigorous documentation to support continuous learning and quality improvement. This approach also highlights the importance of multidisciplinary collaboration among emergency physicians, radiologists, surgeons, and critical care teams to ensure patient‑centered, timely care.

Two questions for readers

1) Have you used point‑of‑care ultrasound to evaluate suspected abdominal emergencies, and what PVG findings have influenced your management decisions?

2) What barriers exist in your practice setting to adopting broader PVG assessment with bedside ultrasound, and how could they be addressed?

Disclaimer: This report is for informational purposes and reflects current clinical discussions. It is indeed not a substitute for professional medical advice, diagnosis, or treatment.

Readers are invited to share experiences and insights in the comments to foster practical learning and ongoing dialog among clinicians navigating complex abdominal emergencies.

> 68‑year‑old male, hypertension, atrial fibrillation Acute mesenteric arterial occlusion on CT angiography Multiple hyperechoic branching lines in left portal vein; “snow‑storm” pattern; no biliary obstruction Laparotomy revealed extensive small‑bowel necrosis; surgical resection saved life. 2 42‑year‑old female, Crohn’s disease, on steroids Severe flare with toxic megacolon Shining tubular echoes moving with portal flow; co‑existing thickened bowel loops (>5 mm) emergency colectomy; histology confirmed transmural necrosis. 3 55‑year‑old male, recent ERCP for choledocholithiasis Post‑procedural abdominal pain, elevated lactate Isolated linear echoes in right portal branch; absent in hepatic veins Repeat CT showed small amount of intra‑hepatic gas; managed conservatively with antibiotics; PVG resolved on repeat ultrasound at 24 h.

Key Learnings from the Series

Bedside Ultrasound Detects Portal venous Gas in Severe Abdominal Emergencies: A Case Series

Portal venous Gas (PVG) – Swift Clinical Snapshot

• Definition: Hyperechoic, mobile, tubular or branching artifacts within the portal venous system on ultrasound.
• Common etiologies: Mesenteric ischemia, bowel necrosis, severe enterocolitis, obstructive pathology, iatrogenic air entry.
• Prognostic relevance: Presence of PVG is linked to higher mortality (up to 75 % in untreated mesenteric infarction) and often mandates urgent surgical or endovascular intervention.

Why Bedside (Point‑of‑Care) Ultrasound?

• Speed: Real‑time visualization in <2 minutes, crucial for "golden hour" decisions.
• Portability: Can be performed in resuscitation bays, ICU, or pre‑operative settings without moving unstable patients.
• Non‑invasive & repeatable: No radiation, allows serial assessments for dynamic changes.

Technical Tips for Reliable PVG detection

Step	Details
Probe selection	Curvilinear 2-5 MHz for deep hepatic imaging; linear 5-10 MHz for superficial vessels.
Patient positioning	Supine; slight left lateral tilt may improve portal vein exposure.
Scanning windows	Intercostal (right subcostal) and subcostal longitudinal view of the porta hepatis.
Image settings	Low mechanical index (MI < 0.2), high gain for subtle echoes; avoid excessive compression.
Artifact differentiation	PVG: mobile, reverberation‑free, follows blood flow; vs. biliary gas (static, within ducts).
Color Doppler	Turn off to avoid masking micro‑bubbles; use pulsed‑wave doppler after gray‑scale detection to confirm flow direction.

Case Series Overview (Three Real‑World Presentations, 2024-2025)

Case	Patient Profile	Triggering Event	Ultrasound Findings	Confirmatory Imaging / Outcome
1	68‑year‑old male, hypertension, atrial fibrillation	Acute mesenteric arterial occlusion on CT angiography	Multiple hyperechoic branching lines in left portal vein; “snow‑storm” pattern; no biliary obstruction	Laparotomy revealed extensive small‑bowel necrosis; surgical resection saved life.
2	42‑year‑old female,Crohn’s disease,on steroids	Severe flare with toxic megacolon	Bright tubular echoes moving with portal flow; co‑existing thickened bowel loops (>5 mm)	Emergency colectomy; histology confirmed transmural necrosis.
3	55‑year‑old male, recent ERCP for choledocholithiasis	Post‑procedural abdominal pain, elevated lactate	Isolated linear echoes in right portal branch; absent in hepatic veins	Repeat CT showed small amount of intra‑hepatic gas; managed conservatively with antibiotics; PVG resolved on repeat ultrasound at 24 h.

Key Learnings from the Series

1. PVG can appear within minutes of a vascular insult – early bedside scanning captured gas before CT.
2. Combined with clinical markers (lactate > 4 mmol/L, peritoneal signs), PVG reliably stratified patients requiring operative care.
3. resolution monitoring – serial ultrasounds documented disappearance of PVG in the conservatively managed case, supporting non‑operative decision.

Diagnostic Accuracy Compared with CT

• Sensitivity: Bedside ultrasound 84 % (95 % CI 71-93 %) for detecting PVG when performed by trained emergency physicians (Kim et al., 2022).
• Specificity: 92 % – false‑positives mainly due to reverberation from bowel gas.
• CT remains gold standard for anatomic detail, but ultrasound provides immediate bedside triage.

Clinical Decision‑Making Flowchart

Severe abdominal pain → Immediate POCUS (hepatic portal view)  


│  


├─ PVG detected? ──► Yes → Assess hemodynamics, lactate, peritonitis →  


│                     • Instability/ peritonitis → Urgent surgery/ angiography.  


│                     • Stable, low lactate → Consider conservative mgmt, repeat US q12‑h.  


│  


└─ No PVG → Continue standard work‑up (labs, CT if indicated).  

Practical Tips for Emergency Physicians

• Pre‑scan checklist: Verify probe,turn off harmonic imaging,set low MI.
• Rapid mental map: Start at the main portal vein, sweep laterally to left and right branches; watch for moving bright lines.
• Documentation: Capture cine loop (≥3 s) of the affected segment; label “PVG” in the report for radiology correlation.
• Team dialog: Immediately inform surgical and critical care teams when PVG is visualized; include lactate trend.

Benefits of Early PVG Identification via ultrasound

• reduced time to definitive care – median door‑to‑OR time shortened by 38 % in institutions adopting POCUS protocols (Bauer et al., 2020).
• Lower radiation exposure – especially valuable for repeat assessments in critically ill or pregnant patients.
• Cost efficiency – bedside ultrasound eliminates need for immediate CT in >30 % of low‑risk patients, saving up to $1,200 per case.

Limitations & Pitfalls

• Operator dependence: Inexperienced users may misinterpret reverberation artifacts as PVG.
• Obesity & bowel gas: can obscure portal view; consider using low‑frequency curvilinear probe or trans‑esophageal echo in extreme cases.
• Confounding conditions: Pneumobilia, hepatic pyogenic abscesses with gas may mimic PVG; always correlate with clinical picture.

Future Directions

• AI‑assisted POCUS: Machine‑learning algorithms are being trained to flag PVG automatically, showing 95 % agreement with expert readings (Li et al., 2024).
• Portable handheld devices: Next‑gen battery‑powered scanners promise sub‑10‑second portal scans,ideal for pre‑hospital settings.
• Multicenter registries: Ongoing prospective studies aim to refine PVG severity scores integrating ultrasound grade, lactate, and hemodynamics.

Quick Reference Guide (Bullet Summary)

• Indications: Acute abdominal pain with suspected ischemia, perforation, severe infection, or post‑endoscopic complications.
• Scanning protocol: Right subcostal longitudinal view → portal vein → liver hilum → left/right branches.
• positive sign: Mobile hyperechoic branching lines moving with portal flow, no shadowing.
• Next steps: Evaluate clinical stability, order labs (lactate, CBC, CRP), consider immediate surgical consult.
• Follow‑up: Repeat POCUS every 12-24 h in conservative cases; document resolution or progression.