01Approach to the Critical Patient/attcp56

Immediate priorities

›Tension pneumothorax recognition and response

›Hemodynamic instability with unilateral absent breath sounds

›SBP < 90 mmHg

›Tracheal deviation away from affected side

›Distended neck veins with respiratory distress

›Late and inconsistent sign

›Absence does not exclude tension physiology

›If tension physiology suspected, immediate needle decompression without delay for imaging

›2nd intercostal space midclavicular line

›14G angiocatheter

›Follow with chest tube regardless of decompression success

›4th to 6th ICS anterior or mid-axillary line safe triangle

›Class I recommendation

›Oxygenation and airway priorities

›High-flow supplemental oxygen

›Accelerates pleural air reabsorption approximately 4-fold vs room air

›Target SpO2 >= 94%

›Continuous pulse oximetry

›Trend monitoring for deterioration

›Escalate if falling despite oxygen

›If on positive pressure ventilation, pneumothorax almost always requires chest tube

›Barotrauma risk

›Rapid tension conversion risk

Monitoring and targets

›Monitoring bundle

›Continuous pulse oximetry

›SpO2 target 92% to 96%

02History/hx77

Presentation pattern

›Core symptoms

›Acute-onset unilateral pleuritic chest pain

›Sharp and worsened with breathing

›May radiate to ipsilateral shoulder

›Dyspnea

›May be mild and disproportionate to size in young patients

›More severe in secondary spontaneous pneumothorax

›Onset and triggers

›Often occurs at rest

›Valsalva maneuver or sudden deep inspiration as precipitant

›Exertion at time of onset less common than expected

›Alarm features

›Worsening dyspnea suggesting tension physiology

›Hypotension and hemodynamic instability

›Altered mental status

›Rapidly progressive hypoxia

›Bilateral pneumothorax concern

›Underlying lung disease limiting reserve

›Subcutaneous emphysema extending beyond chest wall

›Large air leak

›Barotrauma if ventilated

Risk factors

›Primary spontaneous risk profile

›Male sex

›M:F ratio approximately 6:1

›Predominantly young males age 15 to 35 years

›Tobacco smoking

03Physical Exam/exam55

Vitals and general

›Vital sign assessment

›Tachycardia

›Most common vital sign abnormality in pneumothorax

›HR > 130 bpm as hemodynamic alarm

›Blood pressure

›Hypotension SBP < 90 mmHg suggests tension physiology

›Pulsus paradoxus if significant mediastinal shift

›Oxygen saturation

›Often normal in small primary spontaneous pneumothorax

›Significant desaturation in secondary spontaneous pneumothorax

›Respiratory rate

›Tachypnea proportional to dyspnea severity

›>= 30 per minute as severity marker

›General appearance

›Degree of respiratory distress

›Young patients may appear deceptively well

›Accessory muscle use as severity marker

›Body habitus

›Tall thin male as classic presentation

›Connective tissue stigmata

Chest examination

›Inspection

›Asymmetric chest expansion

›Reduced excursion on affected side

›Tracheal deviation in tension physiology

›Subcutaneous emphysema

›Palpable crepitus over chest and neck

04Differential Diagnosis/ddx48

Life threats

›Tension pneumothorax

›ICD-10 J93.0

›Hemodynamic instability plus ipsilateral absent breath sounds

›Immediate needle decompression without imaging

›Massive hemothorax

›Dullness to percussion rather than hyperresonance

›Hemorrhagic shock physiology

›Cardiac tamponade

›Beck triad: hypotension, JVD, muffled heart sounds

›Equalization of filling pressures on echo

›Pulmonary embolism

›Acute dyspnea and pleuritic chest pain

›D-dimer elevation

›ICD-10 I26

Close mimics

›Acute coronary syndrome

›ICD-10 I21

›ECG changes from pneumothorax can mimic STEMI

›ST elevation resolves after lung re-expansion

›Pericarditis

›Diffuse saddle-shaped ST elevation

›Pleuritic chest pain with positional component

›Pleuritis without pneumothorax

›Pleuritic chest pain with normal CXR

›Viral or autoimmune etiology

›Boerhaave syndrome

›Esophageal rupture after emesis

05Laboratory Tests/lt33

Routine investigations

›Complete blood count

›Baseline if admission or procedural intervention planned

›Leukocytosis to exclude infectious etiology

›Anemia relevant if hemopneumothorax suspected

›Basic metabolic panel

›Renal function for procedural planning

›Electrolytes for monitoring if hospitalized

›Coagulation studies

›If chest tube insertion planned

›Anticoagulant use pre-procedure assessment

Gas exchange and cardiac markers

›Arterial blood gas

›Hypoxemia and increased A-a gradient in large pneumothorax

›Respiratory alkalosis from tachypnea compensation

›PaCO2 in mmHg for ventilation assessment

›Venous blood gas

›Alternative to ABG for pH and CO2 trending

›Adequate for most monitoring purposes

›Troponin

›Indicated if ECG changes raise concern for ACS

›Typically normal in isolated pneumothorax

›ST elevation in pneumothorax resolves with treatment

›D-dimer

›Only when pulmonary embolism is in differential

›Not routinely indicated for uncomplicated pneumothorax

Selective investigations

›Alpha-1 antitrypsin level

06Diagnostic Tests/dt87

Scoring Systems

›Pneumothorax size estimation methods

›ACCP definition of large pneumothorax

›Apex-to-cupola distance >= 3 cm on upright PA CXR

›Agreement with BTS definition in less than 50% of cases

›BTS definition of large pneumothorax

›Intrapleural distance >= 2 cm at the level of the hilum

›Used in European guidelines

›Light Index for size quantification

›Pneumothorax percentage = 100 minus (DL cubed divided by DH cubed times 100)

›DL = diameter of collapsed lung

›DH = diameter of hemithorax

›Limitation of size-based classification

›Current guidelines emphasize symptoms and clinical stability over size alone

›Small patient with large pneumothorax may be more compromised than large patient with large pneumothorax

›Clinical stability criteria

›Symptoms-based stratification

›Small or minimally symptomatic: observation strategy

›Large or significantly symptomatic: intervention required

›Hemodynamically unstable: emergent decompression

›PSP trial evidence for conservative management

›Brown et al. NEJM 2020 landmark trial

›94.4% resolution at 8 weeks with conservative management

›98.5% resolution with chest tube intervention

›Conservative arm: significantly shorter LOS 1.6 vs 6.1 days

›Conservative arm: fewer complications 8% vs 27%

›Conservative arm: lower 12-month recurrence 8.8% vs 16.8%

MRI

›MRI chest for pneumothorax

›No established role in acute pneumothorax management

›Motion artifact limits quality

›Air appears as signal void limiting characterization

›Problem-solving applications

›Suspected underlying malignancy or complex pleural disease

›Catamenial pneumothorax with endometriosis evaluation

›Contraindications and limitations

›Unstable patients cannot undergo MRI safely

›Availability constraints in acute setting

›CXR and CT preferred for acute management decisions

CT

›CT chest indications

›First episode with suspected underlying lung disease

›Blebs or bullae identified in approximately 89% of PSP patients on CT

›Guides pleurodesis planning

›Equivocal chest radiograph

›Supine patients where CXR sensitivity reduced

›Anterior pneumothorax not visible on PA film

›Recurrent pneumothorax assessment

›Bilateral bulla survey

›Secondary cause evaluation

›Complex cases

›Hemopneumothorax characterization

›Post-procedure complications

›CT findings and performance

›Superior sensitivity vs CXR for small pneumothorax

›Detects occult pneumothorax in trauma patients

›Volumetric size quantification more accurate

›CT volumetric threshold for intervention in trauma

›Pneumothorax greater than 35 mm on CT generally warrants intervention

›Greater than 20% thoracic volume on CXR equivalent

›Bullae and bleb characterization

›Guides surgical planning for bullectomy

›Identifies contralateral disease

Ultrasound

›Point-of-care ultrasound for pneumothorax

›Lung sliding assessment

›Normal lung sliding excludes pneumothorax at that point

›Absent lung sliding is sensitive but not specific

›Pleural adhesions or severe fibrosis can abolish sliding without pneumothorax

›M-mode findings

›Normal seashore sign: granular appearance below pleural line

›Pneumothorax barcode or stratosphere sign: horizontal lines throughout

›Lung point sign

›Transition zone between sliding and absent sliding

›Pathognomonic for pneumothorax

›Identifies approximate pneumothorax border

›A-line predominance with absent comet-tail artifacts

›Horizontal reverberation artifact

›Normal lung shows B-lines comet-tails

›POCUS performance characteristics

›Sensitivity superior to supine CXR in trauma

›Particularly for anterior pneumothorax

›ACEP Level B recommendation for POCUS in trauma assessment

›Limitations

›Subcutaneous emphysema degrades image quality

›Operator experience dependent

›Cannot reliably quantify size

›E-FAST protocol integration

›Standard component of trauma assessment

›Bilateral pleural assessment for pneumothorax

›Combined with cardiac views for tamponade exclusion

07Disposition/dispo47

Discharge criteria

›Small primary spontaneous pneumothorax discharge pathway

›Clinical stability requirements

›Minimal symptoms and comfortable at rest

›SpO2 >= 92% on room air

›Reliable follow-up available within 12 hours to 2 days

›Observation period in ED

›Minimum 3 to 6 hours of observation

›Repeat CXR to exclude progression

›No enlargement on repeat imaging

›Social requirements

›Lives within reasonable distance of emergency services

›Understands return precautions clearly

›Not traveling by air imminently

Admission indications

›Indications for admission

›Large pneumothorax requiring intervention

›Failed needle aspiration

›Chest tube in place on water seal

›Persistent or worsening symptoms after aspiration

›Failed conservative or aspiration management

›Ongoing pain and dyspnea

›Unreliable follow-up or geographic barrier to care

›Lives far from emergency services

›Social situation limiting safe observation

›Secondary spontaneous pneumothorax

›Underlying lung disease with poor pulmonary reserve

›Always consider admission for monitoring

08Treatment/t93

Initial stabilization

›Immediate management

›High-flow supplemental oxygen

›Accelerates reabsorption approximately 4-fold over room air baseline rate of 2% per day

›Use even if SpO2 is normal to promote reabsorption

›Analgesia

›NSAIDs for pleuritic pain

›Acetaminophen adjunct

›Opioids for severe pain

›Continuous monitoring

›Pulse oximetry

›Cardiac monitoring for ECG changes

Conservative and observation management

›Candidates for observation

›Small primary spontaneous pneumothorax

›Minimally symptomatic patient

›Clinically stable with normal vital signs

›Evidence base

›PSP trial NEJM 2020 supports conservative management

›Resolution at 8 weeks 94.4% with conservative vs 98.5% with intervention

›Fewer complications with conservative approach: 8% vs 27%

›Observation protocol

›ED observation 3 to 6 hours minimum

›Repeat CXR to confirm no progression

›Discharge with follow-up in 12 hours to 2 days

Needle aspiration

›Simple needle aspiration technique

›Indications

›Large or symptomatic primary spontaneous pneumothorax

›First-line intervention before chest tube

›Technique

›14 to 16G catheter insertion

›2nd intercostal space midclavicular line

›Aspiration until resistance felt or patient coughs persistently

›Success rates

›Successful in up to 70% of primary spontaneous pneumothorax cases

›Avoids hospitalization if successful

›Failure predictors

›More than 2.5 L aspirated without resistance suggests ongoing leak

›Patient age > 50 years associated with higher failure rate

›If aspiration fails, proceed to chest tube

Ambulatory drainage device

›Ambulatory Heimlich valve device

›Indications

›Symptomatic or large pneumothorax when aspiration fails or preferred

›Hallifax RAMCAT trial Lancet 2020 supporting evidence

›Device characteristics

›8 Fr small-bore catheter with one-way flutter valve

›Allows outpatient management

›Daily follow-up visit required

›Advantages

›Avoids inpatient admission in selected patients

›Non-inferior to inpatient chest tube management

›Limitations

›Requires reliable patient and follow-up infrastructure

›Not suitable for bilateral or tension cases

Chest tube insertion

›Chest tube indications

›Failed needle aspiration

›Persistent symptoms after aspiration

›Immediate aspiration failure

›Tension pneumothorax after needle decompression

›Pneumothorax in mechanically ventilated patient

›Hemopneumothorax

›Chest tube technique

›Small-bore tube preferred for uncomplicated pneumothorax

›7 to 14 Fr pigtail catheter

›Equivalent efficacy to large-bore tube in most cases

›Insertion site

›4th to 6th ICS anterior or mid-axillary line

›Safe triangle: anterior axillary line, posterior axillary line, level of nipple

›Avoid neurovascular bundle along inferior rib margin

›Connection

›Water seal initially

›Routine suction not shown to improve outcomes

›Heimlich valve for ambulatory management

›Air leak assessment

›Continuous bubbling suggests ongoing air leak

›Air leak typically ceases within 3 days

›Persistent air leak > 5 days warrants surgical referral

Recurrence prevention

›Smoking cessation

›Most important modifiable intervention

›4-fold recurrence risk reduction with smoking cessation

›OR 0.26 for recurrence with cessation (95% CI 0.10 to 0.63)

›Surgical intervention indications

›After first contralateral pneumothorax

›After first recurrence on same side

›Persistent air leak > 3 to 5 days

›Bilateral simultaneous pneumothorax

›VATS with pleurodesis and bullectomy

›Preferred definitive procedure

›Recurrence reduction to < 5% with thoracoscopic pleurodesis

›Talc insufflation, pleural abrasion, or stapling of blebs

›Bullectomy alone without pleurodesis associated with higher recurrence

›Chemical pleurodesis via chest tube

›Talc or doxycycline instillation

›Reduces recurrence to approximately 25%

›Inferior to surgical pleurodesis but less invasive option

09Special Populations/sp63

Pregnancy

›Pneumothorax in pregnancy

›Physiologic considerations

›Diaphragm elevation from gravid uterus reduces reserve

›Increased oxygen demand in late pregnancy

›Any dyspnea warrants higher concern threshold

›Imaging approach

›CXR with abdominal shielding generally safe

›CT when benefits outweigh radiation risk

›POCUS preferred for initial evaluation to limit radiation

›Management principles

›Maternal oxygenation maintenance SpO2 >= 95% for fetal wellbeing

›Fetal heart rate monitoring if viable gestation

›Obstetric consultation for any intervention

›Drug considerations

›NSAIDs: avoid after 20 weeks due to premature ductus arteriosus closure risk

›Acetaminophen safe at all gestational ages

›Opioids: brief use acceptable with fetal monitoring

›Definitive management

›Chest tube approach unchanged if required

›Surgical pleurodesis typically deferred until postpartum unless recurrent and severe

›Delivery mode not altered by history of pneumothorax if pleurodesis performed

Geriatric

›Older adult considerations

›Atypical presentation

›Dyspnea may be attributed to baseline comorbidity

›Pain report may be blunted

›Delayed presentation common

10Background/b83

Epidemiology

›Incidence and prevalence

›Primary spontaneous pneumothorax incidence

›Approximately 18 to 28 per 100,000 per year in men

›Approximately 1.2 to 6 per 100,000 per year in women

›Male predominance M:F ratio approximately 6:1

›Age distribution

›Primary spontaneous pneumothorax: peak age 15 to 35 years

›Secondary spontaneous: older adults with underlying lung disease

›Risk factor prevalence

›Tobacco smoking dominant: up to 22-fold increased risk in moderate smokers

›Familial clustering identified in primary spontaneous cases

›Recurrence data

›Overall 32% recurrence rate after first episode

›Greatest recurrence risk in first year after initial episode

›After first recurrence, second recurrence rate is very high

›Female sex independently associated with higher recurrence OR 3.03

›Asian race associated with increased recurrence HR 1.24

›Mortality and morbidity

›Simple primary spontaneous pneumothorax: very low mortality

›Secondary spontaneous pneumothorax: higher morbidity due to limited reserve

›Tension pneumothorax if untreated: potentially fatal within minutes

Pathophysiology

›Bleb and bulla formation

›Primary spontaneous pneumothorax mechanism

›Subpleural blebs at lung apices most common site

›Blebs or bullae identified in approximately 89% of PSP patients on CT

›Increased apical pleural pressure gradient in tall individuals

›Rupture of bleb allows air into pleural space

›Smoking-related mechanism

›Tobacco causes peribronchiolar inflammation

›Distal airway obstruction leads to air trapping

›Centrilobular emphysema and paraseptal emphysema

›Pleural physiology

›Normal pleural pressure

›Subatmospheric: approximately -5 mmHg at end expiration

›Maintains lung inflation against chest wall recoil

›Pneumothorax effect

›Atmospheric air enters pleural space

›Lung recoil causes partial or complete collapse

›Degree of collapse depends on lung compliance and pleural pressure

›Tension pneumothorax mechanism

›One-way valve effect: air enters on inspiration, cannot exit

›Progressive mediastinal shift

›Cardiovascular compromise from reduced venous return

›Air reabsorption physiology

›Spontaneous reabsorption rate on room air

›Approximately 1.25 to 2% of hemithorax volume per day

›Small pneumothorax resolves over 1 to 3 weeks

›Oxygen supplementation effect

›High-flow oxygen creates nitrogen gradient

›Accelerates reabsorption approximately 4-fold

›Basis for supplemental oxygen in all cases

Therapeutic Considerations

›Conservative vs interventional debate

›Shift toward conservative management for PSP

›PSP trial NEJM 2020 demonstrates non-inferiority of observation

›Resolution rates similar but complications significantly lower with conservation

›Length of stay significantly reduced with conservative approach

›ERS EACTS ESTS 2024 joint guidelines

›Symptom-based rather than size-based approach preferred

›Conservative management appropriate for stable patients regardless of size

›Ambulatory approaches reducing hospital burden

›Heimlich valve devices allow outpatient management

›Hallifax RAMCAT trial demonstrates feasibility

›Aspiration vs chest tube evidence

›Cochrane review 2017: simple aspiration vs intercostal tube drainage

›Similar immediate success rates

›Aspiration associated with less pain and shorter ED stay

›ACEP Level B recommendation for aspiration as first-line in PSP

›Chest tube advantages

›Better for persistent air leak

›Required for mechanically ventilated patients

›More predictable drainage

›Recurrence prevention strategy

›Smoking cessation cornerstone of secondary prevention

›VATS with pleurodesis gold standard for recurrence prevention

›Recurrence rate < 5% post-VATS pleurodesis

›Chemical pleurodesis via tube approximately 25% recurrence

›Timing of definitive surgery

›After first recurrence on same side

›Bilateral disease

›First episode in high-risk occupations (pilots, divers)

›Activity restrictions

›Air travel until complete radiographic resolution typically 2 to 6 weeks

›Scuba diving generally permanently contraindicated without pleurodesis

11Patient Discharge Instructions/pdi37

copy discharge instructions

›What happened

›Diagnosed with a simple pneumothorax (collapsed lung)

›Air has entered the space around your lung

›Your lung is partially or fully collapsed on one side

›This can happen without injury especially in young tall individuals who smoke

›Treatment at home

›Rest and avoid strenuous activity

›No heavy lifting or vigorous exercise until cleared

›Light walking is acceptable

›Supplemental oxygen if prescribed

›Use as directed to help lung re-expand

›Pain management

›Take NSAIDs or acetaminophen as prescribed

›Avoid aspirin and ibuprofen if you have stomach problems

›Critical restrictions

›No air travel until your lung is fully healed

›Typically 2 to 6 weeks at minimum

›Flying can cause the collapsed lung to expand dangerously at altitude

›No scuba diving

›Generally permanently contraindicated unless surgery has been performed

›Pressure changes can cause reoccurrence

›No smoking or vaping

›Smoking dramatically increases recurrence risk

›Ask your doctor for cessation support

›Follow-up appointments

›Return for repeat chest X-ray within 12 to 48 hours

›To confirm the lung is not getting worse

12References/r45

Guidelines and key sources

›Primary clinical guidelines

›Joint ERS EACTS ESTS Clinical Practice Guidelines on Adults With Spontaneous Pneumothorax 2024

›Walker S, Hallifax R, Ricciardi S, et al.

›European Journal of Cardio-Thoracic Surgery 2024

›ERS Task Force Statement: Diagnosis and Treatment of Primary Spontaneous Pneumothorax 2015

›Tschopp JM, Bintcliffe O, Astoul P, et al.

›European Respiratory Journal 2015

›ACCP Delphi Consensus Statement on Management of Spontaneous Pneumothorax 2001

›Baumann MH, Strange C, Heffner JE, et al.

›Chest 2001

Key trials and systematic reviews

›Landmark trials

›PSP Trial: Conservative versus Interventional Treatment for Spontaneous Pneumothorax

›Brown SGA, Ball EL, Perrin K, et al.

›New England Journal of Medicine 2020

›Conservative management non-inferior with fewer complications and shorter LOS

›RAMCAT Trial: Ambulatory Management of Primary Spontaneous Pneumothorax

›Hallifax RJ, McKeown E, Sivakumar P, et al.

›Lancet 2020

›Ambulatory device non-inferior to inpatient management

›Cochrane Review: Simple Aspiration versus Intercostal Tube Drainage

›Carson-Chahhoud KV, Wakai A, van Agteren JE, et al.

›Cochrane Database Systematic Reviews 2017

›Recurrence Rates in Primary Spontaneous Pneumothorax: Systematic Review and Meta-Analysis

›Walker SP, Bibby AC, Halford P, et al.

›European Respiratory Journal 2018

Evidence & Review

Evidence & Review