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Pneumothorax: recognition, decompression and drainage

Assess, manage and stay safe — enough on its own

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The card — assess, manage, caution

Assessment— look, ask, measure

The two cardinal symptoms: sudden-onset unilateral pleuritic chest pain and breathlessness occur in nearly all patients, with cough commonly reported; onset is abrupt, frequently at rest, and the patient can often name the moment.
Pain that settles is not a pneumothorax that settles: pleuritic pain typically eases over 24 hours even when the pneumothorax persists, so resolving pain never means resolving pneumothorax.
Ask what lung is underneath: COPD, tuberculosis, asthma, cystic fibrosis, bronchiectasis, interstitial or fibrotic lung disease, lung cancer, lung abscess, necrotising pneumonia, Pneumocystis jirovecii pneumonia with HIV, or cystic lung disease makes this a secondary pneumothorax — a different and far more dangerous illness at the same size.
Ask what provoked it: blunt or penetrating trauma, thoracentesis, pleural biopsy, subclavian or internal jugular catheterisation, percutaneous lung biopsy, bronchoscopy with transbronchial biopsy, pacemaker insertion, or any positive-pressure ventilation including NIV, CPAP and bag-valve-mask.
Know the two age peaks: primary spontaneous pneumothorax peaks in tall thin males aged 15–30 years and under 45 years, strongly linked to smoking, cannabis, Marfan and Ehlers-Danlos syndromes, while secondary spontaneous pneumothorax occurs mainly in males over 55 years — in old age a spontaneous pneumothorax is invariably secondary and carries significant mortality.
Look for tension before anything else: rapidly progressive breathlessness with marked tachycardia, hypotension, cyanosis and tracheal displacement away from a silent, hyper-resonant hemithorax is tension pneumothorax until proved otherwise.
Tension may occur without mediastinal shift if malignancy or scarring has splinted the mediastinum, so a central trachea does not exclude it — hypotension and hypoxaemia with a silent hyper-resonant hemithorax is the more reliable evidence.
Inspect and palpate: reduced chest expansion on the affected side, decreased tactile fremitus, tracheal position in the suprasternal notch, the site of the apex beat, and subcutaneous emphysema crackling beneath the fingers over the chest wall, supraclavicular fossae or neck.
Percuss and auscultate: the combination of absent or diminished breath sounds with a hyper-resonant percussion note is diagnostic of pneumothorax.
A normal chest examination does not exclude a pneumothorax: if it is smaller than 15% of a hemithorax the only abnormality may be mild tachycardia; above 15% the classical signs appear.
Measure and record: pulse, blood pressure, respiratory rate, SpO2, conscious level and the ability to complete a sentence — cyanosis, exhaustion, inability to complete a sentence and falling effort with rising distress mean impending respiratory arrest.
Erect posteroanterior chest radiograph is the diagnostic test: lucency without lung markings between chest wall and lung with the visceral pleura visible as a fine pleural line is diagnostic — but never wait for it in suspected tension.
Size it two ways: greater than 15% of the hemithorax defines a large pneumothorax, and an interpleural distance of ≥ 2 cm at the level of the hilum (≥ 1 cm in a secondary pneumothorax) is the threshold for aspiration; a 2 cm rim already means roughly 50% volume loss.
Screen for the six high-risk characteristics: haemodynamic compromise, hypoxia, bilateral pneumothorax, underlying lung disease (a secondary pneumothorax), age over 50 years with a significant smoking history, and haemopneumothorax — any one indicates a chest drain where it is safe to intervene.
Get an ECG in every adult and check the other side of the film: pneumothorax mimics myocardial infarction, pulmonary embolism and pneumonia, a left-sided primary pneumothorax itself shifts the QRS axis and changes precordial T waves, and bilateral pneumothorax is easily missed when attention fixes on the obvious side.
Know the two radiographic traps: the lung edge is convex in a pneumothorax and concave in an emphysematous bulla, and in a supine or ventilated patient air collects anteriorly so the only sign may be an abnormally radiolucent costophrenic sulcus — the deep sulcus sign.

Management— do this, in order

Tension pneumothorax is decompressed at the bedside on clinical grounds, before any imaging: life-saving immediate release of the positive pressure by inserting a cannula into the pleural space buys the time needed to prepare a chest drain.Doctor / Nurse
Needle decompression in the adult: a 14-16 gauge cannula, the longest available, into the second intercostal space in the mid-clavicular line on the affected side — the side away from which the trachea is deviated.Doctor / Nurse
In a large or muscular adult use the fourth or fifth intercostal space in the anterior-to-mid axillary line within the triangle of safety, where the chest wall is thinner and the needle more reliably reaches the pleura.Doctor / Nurse
Technique: insert perpendicular to the chest wall passing immediately above the upper border of the rib below the chosen space, since the neurovascular bundle runs beneath the rib above; a hiss of air with a falling heart rate and rising blood pressure confirms both diagnosis and effect; withdraw the needle, leave the cannula and secure it.Doctor / Nurse
Children: use approximately 18-20 gauge in an infant or small child and 16-18 gauge in an older child at the same landmark, advanced only as far as necessary.Doctor / Nurse
Stop or minimise any positive-pressure ventilation — it is generating the tension — and remember the cannula is temporary: it blocks, kinks and displaces, so a chest drain must follow immediately.Doctor / NurseNot available at your setup — Chest drain / tube thoracostomy.
In cardiac arrest with suspected tension pneumothorax decompress during CPR, both sides if the side cannot be determined; this is one of the specifically reversible causes of pulseless electrical activity and the reversal is mechanical, not a drug.Doctor / Nurse
Oxygen is a treatment, not just support: supplemental oxygen accelerates reabsorption of pleural nitrogen and speeds resolution; target SpO2 94-98% in most adults and children but 88-92% in those at risk of type II respiratory failure, ideally by fixed-performance Venturi device with blood gas confirmation.
In a shocked, peri-arrest or profoundly hypoxaemic patient give high-concentration oxygen by reservoir mask at 15 L/min and correct the target afterwards.
Analgesia, because pleuritic pain splints the chest and worsens gas exchange: paracetamol 1 g orally or IV every 6 hours to a maximum of 4 g in 24 hours (child 15 mg/kg orally or IV every 4-6 hours, maximum 60 mg/kg in 24 hours) as first line.
Add an NSAID if not contraindicated: ibuprofen 400 mg orally every 8 hours with food (child 5-10 mg/kg orally every 6-8 hours, maximum 30 mg/kg in 24 hours) or diclofenac 50 mg orally every 8 hours, avoided in renal impairment, peptic ulceration, heart failure, dehydration, NSAID-sensitive asthma and pregnancy.
For severe pain or before drain insertion, morphine 2-5 mg IV titrated slowly and repeated every 5-10 minutes to effect (child 0.1 mg/kg IV slowly titrated), halving the starting dose in frail older people, with naloxone 400 micrograms IV (child 10 micrograms/kg IV) immediately available.Doctor / Nurse
Local anaesthetic ceiling: lidocaine maximum 3 mg/kg without adrenaline, approximately 10 mL of 2% solution in a 70 kg adult — calculate and record the volume before drawing up, in children as well as adults.Doctor / Nurse
Needle aspiration is first intervention for a symptomatic pneumothorax with no high-risk characteristic — typically a primary pneumothorax with a rim of 2 cm or more, or greater than 15% of the hemithorax, or significant dyspnoea — and avoids a chest drain in 60-80% of suitable patients.Doctor / Nurse
Aspiration technique: consent, sit the patient up or semi-recumbent at 45 degrees, full asepsis, infiltrate 2% lidocaine to the pleura in the second intercostal space mid-clavicular line, push a 3-4 cm 16-gauge cannula through the pleura immediately above the upper border of the rib below, connect a three-way tap and 50 mL syringe, aspirate up to 2.5 L expelling each syringeful through the side port, stop if more than 2.5 L is removed or resistance is felt or the patient coughs excessively, then dress the site and repeat the chest radiograph in expiration.Doctor / Nurse
Insert an intercostal drain if aspiration fails to inflate the lung, more than 2.5 L was aspirated, the patient was very breathless on admission, after decompression of a tension pneumothorax, in any secondary pneumothorax, with any high-risk characteristic, on mechanical ventilation, or when the cause is trauma.Doctor / NurseNot available at your setup — Chest drain / tube thoracostomy.
Drain technique: the triangle of safety (lateral border of pectoralis major, lateral border of latissimus dorsi, a horizontal line at nipple level at the fifth intercostal space, and the axilla) or equivalently the fourth intercostal space in the mid-axillary line — never below the fifth intercostal space where diaphragm, liver and spleen lie — with full asepsis, generous local anaesthesia and systemic analgesia, blunt dissection through to the pleura and never a trocar, a small-bore 7F to 14F tube connected to an underwater seal or one-way Heimlich valve, firm stitch fixation, the bottle kept upright and below the level of the chest, and radiographic confirmation of position and expansion.Doctor / NurseNot available at your setup — Chest drain / tube thoracostomy.
Conservative management is active treatment: supplemental oxygen to accelerate reabsorption, analgesia, symptomatic treatment of cough and chest pain, rest, serial observation and repeat radiography every 24 hours — asymptomatic spontaneous pneumothoraces may be managed this way irrespective of size, with a patient meeting none of the intervention criteria observed for 6 hours and followed up as an outpatient within 10 days.

Caution— what harms

Never send a patient with suspected tension pneumothorax for imaging undecompressed — the diagnosis is clinical and the film should never be awaited.
Never accept a central trachea as proof there is no tension: the mediastinum may be splinted by malignant disease or scarring, and the physiology is more reliable than the trachea.
Never apply positive-pressure ventilation, NIV, CPAP or bag-valve-mask ventilation to an undrained pneumothorax — these, with penetrating trauma, lung infection and cardiopulmonary resuscitation, are what generate tension, and most tension pneumothoraces are made in hospital.
Never aspirate a traumatic pneumothorax, a tension pneumothorax, a patient on positive-pressure ventilation, a patient with suspected pleural adhesions or bulla, or a hypoxic or haemodynamically compromised patient.
Never drain a bulla: the lung edge is convex in a pneumothorax and concave in a bulla, an old film often shows it, and draining it creates a bronchopleural fistula in a patient with no reserve — where the plain film is ambiguous in a stable patient, CT settles it.
Never insert a drain below the fifth intercostal space and never use a trocar; wrong-side insertion, injury to the intercostal neurovascular bundle and injury to liver, spleen or diaphragm are the recognised procedural disasters.
Clamping an intercostal drain is potentially dangerous and rarely indicated — a clamped drain with a continuing air leak recreates a tension pneumothorax, and clamping must not be done for transport or imaging.
Never read cessation of bubbling in an unexpanded lung as resolution: a drain that neither swings nor bubbles with a lung that has not re-expanded is blocked, kinked or displaced — inspect the full length of the tube and connections and repeat the film.
Never let the drainage bottle rise above the level of the chest or tip over, or water siphons into the pleural space.
Do not exceed 2.5 L on aspiration and stop on resistance or excessive coughing — rapid re-expansion of a large or long-standing pneumothorax causes re-expansion pulmonary oedema with cough, breathlessness and hypoxaemia within minutes to hours.
The post-aspiration chest radiograph is not a reliable indicator of whether a pleural leak remains, so every patient discharged after aspiration must be told to return immediately if they deteriorate.
Do not assume an elderly patient has a primary pneumothorax — spontaneous pneumothorax in old age is essentially always secondary, may present as confusion, falls or simple deterioration, and frail older people are particularly sensitive to opioid respiratory depression, so halve the morphine dose.
Do not stop looking once you have found one pneumothorax: check the other hemithorax for a bilateral pneumothorax, look for an air-fluid level (haemopneumothorax, assume blood acutely and cross-match), and if pneumomediastinum is present consider rupture of the oesophagus or a bronchus.
A normal supine or ventilated film does not exclude a pneumothorax in an unwell patient — look for the deep sulcus sign, an unusually crisp cardiac or diaphragmatic border, or a rising airway pressure with falling saturation and blood pressure on the ventilator, and examine the chest before anything else.

Refer / escalate

Decompress on the spot and call for help immediately for suspected tension, bilateral pneumothorax, pneumothorax on mechanical ventilation, or haemodynamic compromise; refer for CT and surgical repair if bubbling continues beyond 48 hours or the lung fails to re-expand, and for surgical pleurodesis after any second pneumothorax, any bilateral pneumothorax, failure of tube thoracostomy at the first episode, and after a first secondary pneumothorax where respiratory reserve is low.

The card — assess, manage, caution

Pneumothorax: recognition, decompression and drainage — Level 1: CorePrevious Pneumothorax: recognition, decompression and drainage — Level 3: Core practiceNext

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