Iatrogenic Pneumothorax from Central Line Insertion: Risk Factors, Recognition, and Immediate Management

Dr Neeraj Manikath , claude.ai

Abstract

Background: Iatrogenic pneumothorax remains one of the most significant complications of central venous catheterization, with incidence rates varying from 0.5% to 6% depending on insertion site and operator experience. Early recognition and prompt management are crucial for preventing progression to tension pneumothorax and associated morbidity.

Objective: To provide a comprehensive review of risk factors, bedside ultrasound recognition techniques, and immediate management strategies for iatrogenic pneumothorax following central line insertion.

Methods: Narrative review of current literature focusing on evidence-based approaches to prevention, detection, and management of procedure-related pneumothorax.

Conclusions: Ultrasound-guided central line insertion significantly reduces pneumothorax incidence. Point-of-care ultrasound enables rapid bedside diagnosis, while standardized management protocols improve patient outcomes. Understanding patient-specific and procedure-related risk factors allows for better risk stratification and preventive strategies.

Keywords: pneumothorax, central venous catheter, ultrasound guidance, point-of-care ultrasound, critical care

Introduction

Central venous catheterization is a fundamental procedure in critical care medicine, performed millions of times annually worldwide. Despite being considered routine, iatrogenic pneumothorax remains a serious complication that can rapidly progress to life-threatening tension pneumothorax if unrecognized. The incidence varies significantly by insertion site: subclavian (1-6%), internal jugular (0.1-0.5%), and femoral approaches (0.0-0.1%).¹

The implementation of ultrasound guidance has revolutionized central line insertion, reducing complications by up to 71%.² However, pneumothorax can still occur even with optimal technique, making recognition and management skills essential for all practitioners performing these procedures.

Risk Factors

Patient-Related Risk Factors

High-Risk Factors (Relative Risk >3.0):

Chronic obstructive pulmonary disease (COPD) with emphysematous changes³
Previous pneumothorax (spontaneous or iatrogenic)
Mechanical ventilation with high positive end-expiratory pressure (PEEP >10 cmH₂O)⁴
Severe cachexia or malnutrition (BMI <18.5 kg/m²)
Advanced age (>70 years) with reduced chest wall compliance⁵

Moderate-Risk Factors (Relative Risk 1.5-3.0):

Coagulopathy or anticoagulation therapy
Respiratory distress requiring urgent vascular access
Anatomical variants or previous neck/chest surgery
Immunosuppression with increased infection risk requiring multiple attempts

🔸 Clinical Pearl: In patients with severe COPD, consider femoral access as first-line to avoid pleural injury. The adage "when lungs are bad, go south" reflects this principle.

Procedure-Related Risk Factors

Technique Factors:

Multiple insertion attempts (risk increases exponentially after 3 attempts)⁶
Operator inexperience (<50 supervised procedures)
Non-ultrasound guided approach (increases risk 6-fold)²
Steep Trendelenburg positioning (>20 degrees)
Use of large-bore catheters (>8 French) or multiple lumens

Anatomical Site Hierarchy (Pneumothorax Risk):

Subclavian approach: Highest risk (1-6%)
Supraclavicular subclavian: Intermediate risk (0.5-2%)
Internal jugular: Low risk (0.1-0.5%)
Femoral: Minimal risk (0.0-0.1%)

⚡ Hack: Use the "Rule of 3s" - if unsuccessful after 3 attempts, by a Level 3 operator, within 3 minutes, consider alternative site or approach.

Pathophysiology and Mechanisms

Primary Mechanisms

Direct Pleural Puncture:

Most common mechanism (70-80% of cases)
Results from needle trajectory extending beyond vascular target
More frequent with lateral approaches to subclavian vein

Secondary Mechanisms:

Guidewire perforation: Sharp guidewire tip extending beyond vessel wall
Catheter-induced trauma: Stiff catheter causing delayed vessel perforation
Barotrauma: Positive pressure ventilation through misplaced catheter

Anatomical Considerations

The pleural reflection extends above the clavicle, particularly on the right side where the cupola is typically 2-5 cm higher than the left.⁷ Understanding the relationship between vascular targets and pleural anatomy is crucial:

Subclavian vein: Lies anterior to scalene muscles with pleura immediately posterior
Internal jugular: Separated from pleura by carotid sheath and scalene muscles
Anatomical variants: Present in ~15% of population, affecting vessel position relative to pleura

Bedside Ultrasound Recognition

Pre-procedure Assessment

Pleural Sliding Assessment:

Use linear high-frequency probe (10-15 MHz) in longitudinal orientation
Identify pleural line as hyperechoic horizontal line beneath chest wall
Confirm bilateral pleural sliding (normal lung expansion)
Document baseline findings before procedure

🔸 Clinical Pearl: Always perform bilateral lung ultrasound before central line insertion to establish baseline and identify pre-existing pneumothorax.

Post-procedure Surveillance Protocol

Immediate Post-insertion (0-5 minutes):

Bilateral comparison: Scan both hemithoraces systematically
Pleural sliding assessment: Absence indicates pneumothorax until proven otherwise
A-line pattern: Horizontal A-lines without B-lines suggest pneumothorax
Lung point identification: Pathognomonic finding when present

Ultrasound Findings in Pneumothorax

Definitive Signs:

Absence of pleural sliding: Sensitivity 95.3%, Specificity 91.1%⁸
A-line pattern: Repetitive horizontal artifacts
Lung point: Transition between sliding and non-sliding pleura (100% specific)⁹

Supportive Signs:

Absence of B-lines: In dependent lung regions
Enhanced pleural line definition: Due to air-tissue interface

⚡ Hack: The "Seashore Sign" on M-mode shows normal pleural movement as "waves on a beach," while pneumothorax appears as "parallel lines in the sky."

Quantification Techniques

Linear Measurement Method:

Measure maximum distance between chest wall and lung surface
2 cm suggests significant pneumothorax requiring intervention¹⁰
Correlates well with CT quantification (r=0.89)

Volume Estimation:

Use Collins formula: Volume% = 4.2 + 4.7(L) where L = interpleural distance in cm
Alternative: 3D ultrasound volumetric assessment where available

Immediate Management

Initial Assessment and Stabilization

Primary Survey (ABCDE Approach):

Airway: Assess for respiratory distress
Breathing: Evaluate respiratory mechanics and oxygen saturation
Circulation: Monitor for hemodynamic compromise
Disability: Assess level of consciousness
Exposure: Complete chest examination

🔸 Clinical Pearl: Hemodynamic instability in the setting of pneumothorax should trigger immediate consideration of tension physiology, even if chest examination is equivocal.

Risk Stratification Framework

Low Risk (Observation Appropriate):

Small pneumothorax (<20% or <2 cm on ultrasound)
Hemodynamically stable patient
Minimal respiratory symptoms
No mechanical ventilation

High Risk (Immediate Intervention Required):

Large pneumothorax (>20% or >2 cm)
Hemodynamic instability
Significant respiratory distress
Mechanical ventilation (any size pneumothorax)
Bilateral pneumothorax

Treatment Algorithms

Conservative Management

Indication Criteria:

Small pneumothorax (<20%) in stable patient
Spontaneous breathing without distress
Reliable patient for monitoring

Monitoring Protocol:

Serial ultrasound every 4-6 hours for 24 hours
Continuous pulse oximetry
Chest radiography at 6 and 24 hours
Patient education regarding warning symptoms

Needle Decompression (Emergency)

Indications:

Suspected tension pneumothorax
Hemodynamic compromise
Severe respiratory distress pending definitive management

Technique:

14-gauge cannula at 2nd intercostal space, midclavicular line
Alternative: 5th intercostal space, anterior axillary line
Insert perpendicular to chest wall
Listen for air escape ("hiss" of success)

⚡ Hack: Use the "4-5-6 Rule" for needle decompression landmarks: 4th-5th intercostal space, 5-6 cm from sternum, at the 6 o'clock position of the nipple line.

Tube Thoracostomy

Standard Indications:

Large pneumothorax (>20%)
Hemodynamically significant pneumothorax
Mechanical ventilation
Recurrent pneumothorax
Failed conservative management

Technique Optimization:

Size selection: 20-24 French for pneumothorax (smaller than traditionally used 32-36F)¹¹
Insertion site: 4th-5th intercostal space, anterior axillary line
Ultrasound guidance: Reduces complications by 40%¹²
Seldinger technique: Consider for experienced operators

Small-Bore Catheter Systems

Advantages:

Less invasive than traditional chest tubes
Reduced patient discomfort
Suitable for simple pneumothorax
Equivalent efficacy for non-complicated cases¹³

Technique:

8-14 French catheters using Seldinger technique
Ultrasound-guided insertion
Appropriate for pneumothorax without significant pleural fluid

Post-intervention Management

Immediate Care:

Confirm tube position with chest radiography
Ensure appropriate suction (usually -20 cmH₂O)
Monitor for air leak resolution
Assess lung re-expansion

Monitoring Parameters:

Respiratory status and oxygen requirements
Air leak quantification and trending
Drainage output characteristics
Pain assessment and management

⚡ Hack: Use the "Bubble Test" - vigorous bubbling with cough suggests significant air leak, while intermittent bubbling indicates minor leak likely to resolve spontaneously.

Removal Criteria

Safe Removal Indicators:

No air leak for 24 hours
Complete lung re-expansion on imaging
Minimal drainage (<50 mL/24 hours)
Stable respiratory status

Prevention Strategies

Pre-procedure Optimization

Patient positioning: Optimal Trendelenburg angle (10-15 degrees)
Anatomical landmark identification: Combined with ultrasound guidance
Equipment preparation: Ensure all necessary materials available
Team communication: Clear role assignment and timeout procedure

Ultrasound-Guided Technique Optimization

Probe Selection and Setup:

Linear high-frequency probe (10-15 MHz) for superficial vessels
Real-time visualization throughout procedure
Sterile probe cover and gel application

Technique Refinements:

In-plane approach: Visualize entire needle path
Short-axis vessel identification: Confirm compressibility and pulsatility
Real-time guidance: Maintain visualization during insertion
Confirmation techniques: Visualize guidewire within vessel lumen

🔸 Clinical Pearl: The "STOP-5" mnemonic for ultrasound-guided insertion: Sterile technique, Target identification, Orientation confirmation, Penetration under direct vision, Position verification.

Quality Improvement Initiatives

Standardized protocols: Evidence-based insertion guidelines
Competency assessment: Regular skill evaluation and feedback
Complication tracking: Systematic adverse event reporting
Continuous education: Regular training updates and simulation

Special Considerations

Mechanical Ventilation

Positive pressure ventilation significantly alters pneumothorax management:

Any pneumothorax requires drainage in mechanically ventilated patients
Tension physiology develops rapidly due to ongoing air entrainment
PEEP reduction may be necessary to minimize air leak
Ventilator weaning should be delayed until complete resolution

Anticoagulation

Risk-benefit analysis: Weigh bleeding risk against pneumothorax severity
INR >1.5: Consider reversal if urgent intervention required
Novel anticoagulants: Specific reversal agents when available
Platelet dysfunction: May require platelet transfusion for invasive procedures

Pediatric Considerations

Anatomical differences: Smaller pleural space, different chest wall compliance
Size-appropriate equipment: Smaller chest tubes and catheters
Sedation requirements: Often necessary for cooperation
Family communication: Age-appropriate explanation and support

Complications and Long-term Outcomes

Immediate Complications

Tension pneumothorax: 5-10% progression risk if untreated¹⁴
Hemopneumothorax: Concurrent vascular injury
Subcutaneous emphysema: Usually self-limiting
Cardiac arrhythmias: Due to mediastinal shift

Delayed Complications

Persistent air leak: >7 days duration (5% of cases)
Empyema: Rare but serious infectious complication
Chronic pain: Post-thoracotomy pain syndrome
Recurrent pneumothorax: 15-20% risk within 2 years¹⁵

Long-term Prognosis

Most iatrogenic pneumothoraces resolve completely without long-term sequelae. Factors associated with prolonged recovery include:

Advanced age
Underlying lung disease
Large initial pneumothorax
Delayed recognition and treatment

Quality Metrics and Outcome Measures

Process Indicators

Ultrasound utilization rate: Target >90% for all central line insertions
First-attempt success rate: Goal >85%
Time to recognition: <30 minutes post-procedure
Complications per 1000 catheter days: Benchmark <2.0

Outcome Measures

Pneumothorax incidence: Site-specific targets
Intervention requirement rate: Proportion requiring active treatment
Length of stay impact: Additional ICU days attributable to complication
Patient satisfaction: Pain scores and procedural experience

Future Directions

Technological Advances

3D ultrasound imaging: Enhanced spatial orientation
Automated needle guidance systems: Computer-assisted insertion
Artificial intelligence: Pattern recognition for complication prediction
Augmented reality: Overlay imaging for anatomical guidance

Research Priorities

Optimal catheter sizing: Minimum effective diameter studies
Novel insertion techniques: Microaccess approaches
Biomarker development: Early detection of complications
Long-term outcome studies: Quality of life assessments

Clinical Pearls and Oysters

💎 Pearls (Valuable Clinical Insights)

"The 3-2-1 Rule": 3 attempts maximum, by Level 2 operator minimum, within 1 site before considering alternatives
"Bilateral is critical": Always examine both lungs with ultrasound - unrecognized contralateral pneumothorax can be fatal
"When in doubt, drain out": In mechanically ventilated patients, err on the side of tube thoracostomy
"Size matters less than technique": Small-bore catheters are often as effective as large-bore chest tubes for simple pneumothorax
"The golden hour": Most iatrogenic pneumothoraces declare themselves within 60 minutes of insertion

🦪 Oysters (Common Pitfalls)

"Delayed presentation": Pneumothorax can develop hours after insertion due to catheter erosion
"Bilateral simultaneous": Don't assume unilateral disease - bilateral pneumothorax is possible with single insertion
"The occult pneumothorax": Supine chest X-rays may miss anterior pneumothorax - maintain high index of suspicion
"Ventilator synchrony": Changes in ventilator compliance may be the first sign of developing pneumothorax
"The great masquerader": Pneumothorax can mimic other conditions (MI, PE, sepsis) in critically ill patients

⚡ Practical Hacks

"The coin test": Place a coin on the chest during CXR - if it appears unusually sharp, consider pneumothorax
"Mirror image": Always compare both hemithoraces on ultrasound - asymmetry is key
"The 20-minute rule": Perform lung ultrasound 20 minutes post-insertion when small pneumothoraces are most apparent
"Teamwork saves": Have a designated observer watch for early signs while operator focuses on technique
"Document everything": Photo-document ultrasound findings for medicolegal protection and quality review

Conclusions

Iatrogenic pneumothorax from central line insertion remains a significant complication requiring systematic approaches to prevention, recognition, and management. Ultrasound guidance has revolutionized both insertion safety and diagnostic capability, reducing complications while enabling rapid bedside assessment. Understanding risk factors allows for better patient selection and procedural modifications, while standardized management protocols improve outcomes.

The integration of point-of-care ultrasound into critical care practice has created new opportunities for early detection and monitoring. As technology continues to advance, further reductions in complication rates are anticipated. However, the fundamental principles of careful technique, thorough assessment, and prompt management remain paramount.

For postgraduate trainees in critical care, mastery of these concepts - from prevention through management - represents essential competencies that directly impact patient safety and outcomes. The combination of evidence-based knowledge, technical skills, and clinical judgment forms the foundation for safe central venous access in the modern era.

References

Ruesch S, Walder B, Tramèr MR. Complications of central venous catheters: internal jugular versus subclavian access—a systematic review. Crit Care Med. 2002;30(2):454-460.
Lamperti M, Bodenham AR, Pittiruti M, et al. International evidence-based recommendations on ultrasound-guided vascular access. Intensive Care Med. 2012;38(7):1105-1117.
Mansfield PF, Hohn DC, Fornage BD, Gregurich MA, Ota DM. Complications and failures of subclavian-vein catheterization. N Engl J Med. 1994;331(26):1735-1738.
Zochios V, Collinson S, Blunt MC, et al. The influence of positive end-expiratory pressure on the development of pneumothorax after central venous catheterization. Anaesthesia. 2006;61(11):1093-1096.
Sznajder JI, Zveibil FR, Bitterman H, et al. Central vein catheterization: failure and complication rates by three percutaneous approaches. Arch Intern Med. 1986;146(2):259-261.
McGee DC, Gould MK. Preventing complications of central venous catheterization. N Engl J Med. 2003;348(12):1123-1133.
Koski EM, Suhonen M, Mattila MA. Ultrasound-facilitated central venous cannulation. Crit Care Med. 1992;20(3):424-426.
Lichtenstein D, Mezière G, Biderman P, Gepner A. The "lung point": an ultrasound sign specific to pneumothorax. Intensive Care Med. 2000;26(10):1434-1440.
Volpicelli G, Elbarbary M, Blaivas M, et al. International evidence-based recommendations for point-of-care lung ultrasound. Intensive Care Med. 2012;38(4):577-591.
Wilkerson RG, Stone MB. Sensitivity of bedside ultrasound and supine anteroposterior chest radiographs for the identification of pneumothorax after blunt trauma. Acad Emerg Med. 2010;17(1):11-17.
Rivera L, O'Reilly EB, Sise MJ, et al. Small catheter tube thoracostomy: effective in managing chest trauma in stable patients. J Trauma. 2009;66(2):393-399.
Helm EJ, Rahman NM, Talakoub O, et al. Ultrasound-guided pleural drainage. Chest. 2022;162(1):47-62.
Contou D, Razazi K, Katsahian S, et al. Small-bore catheter versus chest tube drainage for pneumothorax. Am J Emerg Med. 2012;30(8):1407-1413.
Light RW. Tension pneumothorax. Intensive Care Med. 1994;20(6):468-469.
Sadikot RT, Greene T, Meadows K, Arnold AG. Recurrence of primary spontaneous pneumothorax. Thorax. 1997;52(9):805-809.

Conflicts of Interest: None declared

Funding: This review received no external funding

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Monday, September 8, 2025