PneumothoraxDefintiion Accumulation of gas in pleural spaceClassification 1Y spontaneous: no underlying lung disease and no external cause; most common in tall, thin men, 20-40yrs,

smokers (0.1% risk in non-smoker male, 12% in smoker), Marfan’s; subpleural blebs and bullae found in up to 90% cases; 50-84% re-expansion rate without intervention2Y spontaenous: underlying lung disease (eg. Ca, COPD, asthma, CF, PCP pneumonia, marjuana use, IVDU, interstitial lung disease, TB, previous pneumothorax) and no external cause or >50yrs with significant smoking history; 33-67% re-expansion without intervention; persistent air leak more common, usually resolves after 1/52; have more pronounced SxTraumatic / iatrogenicLoculated: in patients with pleural adhesions, use USS when drainCatamenial: within 48hrs of menses; >90% on R; 35% have endometriosis; 25% have intrathoracic depositsTension: usually due to trauma / mechanical ventilation; PPV life threatening decr VR and CO

Epidemiology 1/10,000/yr; >70% smokers; recurrence rate 30% (50% according to MCQ), usually within 2yrs; 20% recurrence in 1st year; decr risk of recurrence if >40yrs; incr risk recurrence if young, smoker, pul fibrosis

Risk factors Asthma, COPD, smoking, O2, INH, alcoholism, institutionalisation, immunosuppAssessment History: 90% CP, 80% SOB, 10% cough; more in 2Y than 1Y; history is not good indicator of size on pneumoT

OE: decr BS (75% sens), incr percussion note (10% sens); decr vocal fremitus, hypoxia (in 16% 2Y; related to underlying lung disease and size of pneumothorax) In tension: CP + SOB (in >80%), incr HR and decr AE (in 50-75%), decr SaO2, tracheal deviation, decr BP, incr JVP (in <25%), cyanosis, hyperresonance, decr LOC, hyperexpansion, hypomobility, epiG pain, displaced apex beat, sternal resonance (in 10%); CV changes more prominent if ETT

Investigation CXR: 90-95% sens (if not seen usually don’t require drainage; 80% sens if supine); exp film more sens, but insp better for defining other pathology; exp film not recommended by BTS, rather lateral or lat decubitus if high suspicion and PA normal; see “how to read a CXR”; size on exp film is 9% bigger than on inspUSS: absent sliding lung sign (95% sens, 90% spec; false +ive with ARDS and pul fibrosis); absence of comet tail artefacts (>95% sens, 60% spec); absence of pleural movements on M mode; accuracy less good if have chest drain inCT: 100% sens; better for quantifying size than above; do if ETT, accurate diagnosis essential (eg. Diver); best in trauma; recommended if uncertain / complexECG: shows RAD, decr R wave height in precordial leads, electrical alternans, precordial TWI; in tension may show PR elevation in inf leads, PR depression in aVR

Size of pneumothorax

Size less important than degree of clinical compromise; size does determine rate of resolution and may be relative indication for alteration of managementSmall: BTS guidelines: <2cm at hilum ACCP guidelines: <3cm at apex USS: at mid-clavicular line

Mod: USS: at ant axillary line

Large: BTS guidelines: >2cm at hilum (=>50%) ACCP guidelines: >3cm at apex USS: at mid axillary line

In general: If pleural line >3cm from apex, then >20%Mng O2: high flow; 4x incr in reabsorption rate of air

Trt choice depends on: size, severity of Sx, degree of air leak, whether haemothorax present, 1Y/2Y

1Y: <2cm + minimal Sx: observe 2Y: <1cm + <50yrs + no symptoms: observe >2cm or any size + symptoms: aspirate 1-2cm + <50yrs: aspirate Unstable or aspiration fails: drain >2cm or >50yrs or unstable or aspiration fails: drain

Observation: BTS: small 1Y with minimal Sx very small (<1cm or isolated apical) asymptomatic 2Y ACCP: small 1Y with minimal Sx possibly small asymptomatic 2Y as above 1Y: observe 3-6hrs rpt CXR discharge if no progression rpt CXR 24hrs rpt CXR 3-5/7; good patient discharge advice

Average interpleural distance technique: (at apex + middle of upper ½ + middle of lower 1/2) / 3 1 = 14% 2 = approx 20% 3 = approx 30% 4 = approx 40% 5 = approx 50%

Light’s formula: distance from hilum to lung edge3 / distance from hilum to lat chest wall3

2Y: admit all Outcome: 2% expansion rate per day; successful in 80-90% 1Y’s Pros: high rate of success, avoid hospitalisation, avoids procedure complications, patient acceptance Cons: risk of progression / tension, need for ED observation, failure in up to 40%, potential for long time until resolution of Sx

Aspiration: Indication: BTS: 1Y symptomatic may be 1Y large 2Y <2cm / <50yrs ACCP: doesn’t really favour aspiration Iatrogenic (needle-induced – may be suitable for observation), stable isolated traumatic

Technique: 14-16G needle or Seldinger 8-16F catheter; sit up 45deg, 2nd ICS mid-clavicular line or 4th-5th

ICS ant to mid axillary line aspirate up to 3L rpt CXR rpt aspiration not recommended if failure, unless there were technical difficulties 1st time (80% will fail again) admit all 2Y’s for at least 24hrs and refer early to respiratory physicians admit failed trt 1Y’s (Continued leak if >3L aspirated / >300ml aspirated after cough) discuss with thoracic surgeon if ongoing at 48hrs admit SSU if successful rpt CXR at 4hrs discharge if no re-expansion rpt CXR at 24hrs rpt CXR 3-5/7; good patient discharge advice Outcome: successful in 70% (50-83% 1Y’s, 50% 2Ys, 75% 2Y’s <50yrs, 25% 2Y’s >50yrs; 90% if <3L air aspirated, <5% if >3L); 15% 1yr recurrence rate Vs chest drain: pros: no difference in immediate success rate, early failure rate, duration of hospitalisation, 1yr success Rate; lower complication rate; shorter LOS; decr admission rate Pros: high success rate in selected patients; cheap; less painful; simple Cons: maybe failure; may be more time consuming for ED than IDC and admission

Chest drain insertion:Indication: BTS: unstable; failed other trt 2Y >2cm / >50yrs ACCP: unstable; failed other trt; large 1Y All 2Y’s Tension, ventilated, bilateral, traumatic (unless needle induced, small and presents late, detected on CT only) Technique: Safe triangle = ant border of lats, lat border of pec major, sup to line joining nipple to tip of scapula

Use 10-16F (only larger bore (24-28F) if haemothorax or failed re-expansion; no benefit from large bore otherwise); check plts, coag, have IVA; skin incision 1-2cm below rib finger sweep 360deg within cavity place apicoposterior for pneumo, posterobasilar for haemo insert at least 3-4cm beyond last hole, usually 10- 12cm connect to Heimlich valve or underwater seal check for bubbles and swinging, fogging check CXR after for position / complications / success removal when lung re-expanded on CXR and no evidence of air leak for 24hrs; remove unclamped tube during expiration Give IV cephazolin only if penetrating chest trauma; never clamp bubbling chest tube, BTS doesn’t recommend clamping, ACCP uncertain; add suction if persistent air leak or failure to reexpand (no evidence it helps; BTS recommends only after 48hrs using high vol low p system; may cause re-expansion pul oedema) Outcome: 90% success for 1st pneumothorax, 52% success for 1st recurrence, 15% success for 2nd recurrence Pros: effective; 66-97% success in 1Y Cons: requires hospitalisation (usually 1/52), complication risk (haemorrhage from intercostal / int mammary artery, bronchopleural fistula, surgical emphysema, misplacement (4-9%), damage to adjacent structures, infection (1% empyema rate, higher if penetrating trauma), re-expansion pul oedema (1%; rarely assoc with clinical Sx, may develop in untreated lung also; incr risk if large pneumothorax, <30yrs, late presentation >1/52, >3L fluid – so do gradual evacuation eg. 500ml/hr, avoid suction), patient discomfort

OT: chemical pleuroesis, open thoracotomy and pleurectomy, mini thoracotomy, thoracoscopic; younger patients more likely to benefit Indication: 2nd ipsilateral pneumoT, 1st contralat pneumoT, bilateral spontaneous pneumoT, persistent air leak >5/7, failure to re-expand, spontaneous haemoT, professions (eg. Pilot, diver – do after 1 st episode)

Tension: high flow O2 CXR (if CXR not available, drain ASAP if: SaO2 <92%, SBP <90, RR <10, decr LOC, pre-arrest or arrest) needle thoracocentesis immediate chest drain

Discharge advice

Written and verbal; all should be followed up by resp physicians until full resolutionAvoid: flying (within 6/52 of resolution or OT, with recent CXR showing resolution; significant risk of reoccurence up

to 1yr), scuba diving (permanently unless definitive OT, unless traumatic), snorkelling

Notes from:

BTS GUIDELINES 2010: