How do you set the ventilator for a patient with a pneumothorax?

Published 2026-09-14 · Updated 2026-09-14 · Last checked against sources 2026-09-14

Before I looked it up

Ventilator settings for a pneumothorax patient. In truth every case is different, so it is hard to say uniformly that such-and-such a setting should be used, but through the many papers and case reports, the methods that help pneumothorax patients seem to have reached a certain consensus. I organised it, partly to study..

What I found

The note I started from was a settings table — tidal volume 4–6 mL/kg, PEEP 3–5, plateau under 25 — with “BTS/ACCP guidelines” and “ARDSNet (adapted)” as its references. I went looking for where each number came from. Three things first.

• There is no guideline for ventilating a pneumothorax. The 2023 BTS guideline excludes pneumothorax on mechanical ventilation from its evidence review. What the BTS documents do say is one thing: a ventilated patient with a pneumothorax gets a chest drain, and a large-bore one. Everything else — the principles in my note — is consensus assembled from case reports, two animal models and physiology. The 2021 Critical Care Medicine review that collects it describes its own data as “largely from case reports”. So what I wrote before looking — that a consensus seems to exist — is exactly right. It is a consensus about direction, not about numbers.
• PEEP drives the leak about six times harder than peak pressure. In a rabbit bronchopleural fistula model, raising peak inspiratory pressure from 10 to 30 cmH₂O did not significantly change the fraction of tidal volume lost; raising PEEP from 0 to 16 did. Any PEEP above 6 cmH₂O leaked more than any level of peak pressure. That single experiment is the real source of the “3–5” in my note.
• A tidal volume of 4 mL/kg was harmful in the only experiment that tested it. In a pig fistula model, 4 mL/kg dropped arterial saturation to about 84% with severe hypercapnia; 7 mL/kg with zero PEEP was best — saturation held near 90% and the leak was smaller than at 10 mL/kg. PEEP increased the leak at every tidal volume. The lower end of my “4–6” has no source, and where it was tested it hurt.

The rest of what I found, in order.

• Plateau under 25 (or 20): no primary source. ARDSNet uses 30. “Stricter than usual” is a reasonable direction, but 25 and 20 are not measured thresholds. The pressure metric with survival data behind it is driving pressure (Amato 2015).
• pH above 7.20: no primary source. The ARDSNet protocol raises the respiratory rate for pH 7.15–7.30 (to a maximum of 35) and below 7.15 allows bicarbonate and raises tidal volume in 1 mL/kg steps, letting the plateau exceed 30. The 7.20 in my note is a habit somewhere between those two.
• SpO₂ 88–92%: the ARDSNet target is 88–95% (PaO₂ 55–80). The 92 ceiling has no source.
• I:E ≥ 1:2, avoid auto-PEEP: same direction as the review’s principles (shorter inspiratory time, lower rate). The ratio itself is convention.
• HFOV/HFJV — the evidence points the other way. In seven ventilated patients with a fistula, switching to high-frequency jet ventilation worsened oxygenation in six of seven, left the leak unchanged, and conventional ventilation was so clearly superior that nobody was randomised. In ARDS, high-frequency oscillation was stopped early for harm (OSCILLATE, mortality 47% versus 35%) and the 2017 ATS/ESICM/SCCM guideline recommends strongly against routine use. In the fistula literature it is “a trial if conventional manipulation fails” — nothing more.
• Independent lung ventilation and ECMO: case series. In a COVID VV-ECMO cohort of 152, ten developed refractory air leaks; endobronchial valves stopped the leak in all ten immediately and 80% survived to discharge.
• Chest drain suction: the BTS procedures statement says no routine suction (no evidence of benefit), avoid it soon after insertion (re-expansion oedema), and if used, low-pressure, high-volume, maximum −20 cmH₂O. Same direction as my note’s “excessive suction worsens the leak” — suction is negative intrapleural pressure, and the review lists limiting it as one of the three things to do. Clamping a bubbling drain risks tension.
• Tension pneumothorax on a ventilator does not announce itself with tracheal deviation and neck veins. A systematic review of 183 cases: with assisted ventilation, the adjusted odds of hypotension were 12.6-fold and of cardiac arrest 17.7-fold compared with unassisted breathing; in one cohort 39.6% presented pulseless; 70% of the hypotension or arrest came within minutes. The first signs are hypoxia (92%), hypotension and a rising peak pressure.
• Needle decompression: the second intercostal space at the midclavicular line fails 38% of the time with a 5 cm catheter, the fourth or fifth space at the anterior axillary line 13%; ATLS 10th edition moved adults to the fifth space. My note had the old site — same correction as my pneumothorax note.
• “Positive pressure itself worsens a pneumothorax”: it enlarges an existing leak, yes — that is the pressure gradient. But barotrauma itself was not predicted by ventilator settings in 5,183 ventilated patients (settings did not differ between those with and without barotrauma; the underlying lung disease did).

What I was reading

The 2021 Critical Care Medicine concise review of bronchopleural fistula on mechanical ventilation (Grotberg and colleagues — abstract and summaries; the full text is paywalled), the BTS Clinical Statement on pleural procedures 2023 (full text), the BTS pleural disease guideline 2023 (read for my pneumothorax note), two animal models (Dennis 1980, rabbits; Toneloto 2008, pigs), the one patient comparison of high-frequency ventilation (Bishop 1987, n = 7), the ARDSNet trial and its protocol, Amato 2015, the ATS/ESICM/SCCM 2017 and ESICM 2023 ARDS guidelines, OSCILLATE, the 2015 systematic review of tension pneumothorax presentation, Anzueto 2004 on barotrauma, and Laan 2016 on decompression. The note I started from cited “BTS/ACCP guidelines” without editions: BTS is the 2023 document (replacing 2010), ACCP is a 2001 Delphi consensus, and neither says anything about ventilator settings. The “(adapted)” after “ARDSNet protocol” was already a confession that the numbers had no source of their own. What follows is what I read in September 2026.

0. What the evidence actually is

Evidence: one narrative review synthesising case reports and physiological studies (2021), two animal experiments, one patient comparison (n = 7). No randomised trial. No guideline.

• There is no randomised trial of ventilation strategy in pneumothorax or bronchopleural fistula on mechanical ventilation. The review that collects the literature says its data are “largely from case reports”.
• So the consensus is a direction: reduce the pressure gradient across the fistula and the leak falls. The numbers — 4–6, 3–5, under 25, 7.20 — are mostly that direction translated into habit. Two numbers have a primary source: PEEP under 6 (rabbit) and tidal volume 7 over 4 (pig).
• What guidelines do say: BTS 2023 — mechanical ventilation raises the risk of tension and of bronchopleural fistula, so a chest drain rather than aspiration; a pneumothorax from barotrauma does better with a large-bore drain (small-bore drains have lower success rates); no routine suction, maximum −20 cmH₂O. ATS/ESICM/SCCM 2017 and ESICM 2023 (ARDS) — tidal volume 4–8 mL/kg predicted body weight, plateau under 30, strong recommendation against routine HFOV. They do not address pneumothorax separately.

1. First, the chest drain

Strength: BTS 2023 practice points · systematic review (Roberts 2015).

• A ventilated patient with a pneumothorax gets a chest drain, not needle aspiration — positive pressure raises the likelihood of tension and of fistula (BTS procedures statement: “chest drain preferred”).
• Size: a pneumothorax complicating barotrauma is better managed with a large-bore drain (over 14 F); smaller drains appear to have lower success rates. Large air leaks — trauma, secondary pneumothorax, ventilated patients — need a large-bore drain.
• CPAP and NIV count as positive pressure: if a pneumothorax was the reason for the drain, a functioning, open drain must be in place before CPAP is considered (BTS, re-expansion oedema box).
• Positive pressure without a drain → tension. Emergency decompression at the fifth intercostal space, anterior axillary line (Laan 2016; ATLS 10th edition), then a drain.

2. Initial settings — my note’s table, rewritten with the strength of the evidence

Strength: marked per row. “Convention” = no primary source found.

3. Cautions

Auto-PEEP. Adequate expiratory time — shorter inspiratory time and lower rate are the review’s principles. Air trapping is intrinsic PEEP, and PEEP is what drives the leak hardest.

Permissive hypercapnia.

Strength: the ARDSNet protocol rules (inside an RCT) · a review.

• Pressure before CO₂ — the direction is consensus. The thresholds with a source are ARDSNet: pH 7.15–7.30 → raise the rate (maximum 35); below 7.15 → rate 35, bicarbonate may be given, tidal volume up in 1 mL/kg steps and the plateau may exceed 30. My “above 7.20” is an unsourced midpoint.
• Bicarbonate: ARDSNet permitted it; the evidence of benefit in acute respiratory acidosis is weak and it generates CO₂. “Consider” is as far as it goes.

Air-leak monitoring.

• Watch the pattern (inspiratory only, or continuous); leak up → pressure down — the review’s principle. Digital drainage devices quantify the leak, and the BTS statement says they may have a role in pneumothorax.
• Persistent leak → bronchopleural fistula.
• Suction: not routine; avoid soon after insertion; if used, low-pressure high-volume, maximum −20 cmH₂O (BTS). Suction is negative intrapleural pressure — the third of the review’s three things to limit.

Signs of tension — different on a ventilator.

Evidence: systematic review — five cohorts (310 patients) plus 183 case reports (Roberts 2015).

• With assisted ventilation: hypoxia 91.8% (versus 50% breathing unassisted), hypotension OR 12.6, cardiac arrest OR 17.7, 39.6% pulseless at presentation in one cohort, and 70.4% of the hypotension or arrest within minutes.
• So my note’s “sudden BP drop, rising peak pressure, absent breath sounds on one side” is right, and tracheal deviation and jugular distension are late or absent. Waiting for them is waiting too long.

4. Special situations

Bronchopleural fistula with a massive leak.

Strength: case series and reviews. No RCT.

• Independent lung ventilation: a double-lumen tube, the leaking side on low pressure or CPAP only, the other side ventilated normally. Case series and reviews (Anantham 2005; Berg 2019). “Consider in refractory cases” (the 2021 review).
• HFOV/HFJV: the evidence points the other way. Seven fistula patients (Bishop 1987): on switching to jet ventilation, oxygenation worsened in six of seven, PaCO₂ rose from 47 to 56, the leak did not change, and conventional ventilation was superior by prespecified criteria in every patient, so none was randomised. In ARDS, OSCILLATE (mortality 47% versus 35%, stopped early) and a strong recommendation against routine HFOV (ATS/ESICM/SCCM 2017). In the fistula literature, high-frequency ventilation is “a trial when conventional manipulation fails” (Baumann and Sahn 1990) — not more.
• Suction: excessive suction worsens the leak — the review and BTS (section 3).
• Endobronchial valves and occlusion devices: the definitive end of the refractory pathway (the 2021 review). In 152 COVID VV-ECMO patients, ten refractory leaks were treated with valves — immediate cessation in all ten, weaning from ECMO and the ventilator, 80% survival to discharge (Ficial 2023).

Bilateral pneumothorax. Bilateral drains — obviously. “Even lower pressures” — the principle. ECMO — case reports and series (“in appropriate patients”, the 2021 review): rest the lungs so the leak can close.

What I take from it

1. Chest drain first, large-bore. That is the only part with a guideline behind it.
2. The leak is the pressure gradient — peak pressure, PEEP, inspiratory time, rate and suction all down. Direction over numbers.
3. PEEP under 6. The one number with an experiment behind it; PEEP is six times peak pressure.
4. Tidal volume low, but 4 was harmful — 7 beat 4 in pigs. Around 6, watching the leak and the saturation.
5. Plateau 25 and 20, pH 7.20 are habits — ARDSNet says 30 and 7.15. The pressure with survival data is driving pressure.
6. HFOV is not the answer — worse oxygenation in fistula patients (1987), more deaths in ARDS (2013).
7. Tension on a ventilator arrives as hypotension or pulselessness within minutes. Do not wait for the trachea to move.
8. Decompress at the fifth intercostal space, anterior axillary line.
9. From inside a hospital — the consensus I sensed before looking is real, and it is thinner than it feels: a review of case reports, a rabbit, five pigs, seven patients. Individualise, and write down why.

Sources

Reviews of bronchopleural fistula on mechanical ventilation

• Grotberg JC, Hyzy RC, De Cardenas J, Co IN. Bronchopleural Fistula in the Mechanically Ventilated Patient: A Concise Review. Crit Care Med. 2021;49(2):292-301. doi:10.1097/CCM.0000000000004771 · PMID 33372747
• Baumann MH, Sahn SA. Medical management and therapy of bronchopleural fistulas in the mechanically ventilated patient. Chest. 1990;97(3):721-728. doi:10.1378/chest.97.3.721 · PMID 2407455
• Shekar K, Foot C, Fraser J, et al. Bronchopleural fistula: an update for intensivists. J Crit Care. 2010;25(1):47-55. doi:10.1016/j.jcrc.2009.05.007 · PMID 19592205

Experiments and the one patient comparison

• Dennis JW, Eigen H, Ballantine TV, Grosfeld JL. The relationship between peak inspiratory pressure and positive end expiratory pressure on the volume of air lost through a bronchopleural fistula. J Pediatr Surg. 1980;15(6):971-976. doi:10.1016/s0022-3468(80)80312-5 · PMID 7007608
• Toneloto MG, Terzi RG, Silva WA, Moraes AC, Moreira MM. Effects of different tidal volumes and positive end expiratory pressure on gas exchange in experimental bronchopleural fistula. Rev Bras Ter Intensiva. 2008;20(3):254-260. PMID 25307093
• Bishop MJ, Benson MS, Sato P, Pierson DJ. Comparison of high-frequency jet ventilation with conventional mechanical ventilation for bronchopleural fistula. Anesth Analg. 1987;66(9):833-838. PMID 3304022

Pleural guidelines

• Asciak R, Bedawi EO, Bhatnagar R, et al. British Thoracic Society Clinical Statement on pleural procedures. Thorax. 2023;78(Suppl 3):s43-s68. doi:10.1136/thorax-2022-219371 · PMID 37433579
• Roberts ME, Rahman NM, Maskell NA, et al. British Thoracic Society Guideline for pleural disease. Thorax. 2023;78(Suppl 3):s1-s42. doi:10.1136/thorax-2022-219784 · PMID 37433578

Ventilation in ARDS — the borrowed thresholds

• Acute Respiratory Distress Syndrome Network; Brower RG, Matthay MA, et al. Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. N Engl J Med. 2000;342(18):1301-1308. doi:10.1056/NEJM200005043421801 · PMID 10793162
• Amato MB, Meade MO, Slutsky AS, et al. Driving pressure and survival in the acute respiratory distress syndrome. N Engl J Med. 2015;372(8):747-755. doi:10.1056/NEJMsa1410639 · PMID 25693014
• Fan E, Del Sorbo L, Goligher EC, et al. An Official American Thoracic Society/European Society of Intensive Care Medicine/Society of Critical Care Medicine Clinical Practice Guideline: Mechanical Ventilation in Adult Patients with Acute Respiratory Distress Syndrome. Am J Respir Crit Care Med. 2017;195(9):1253-1263. doi:10.1164/rccm.201703-0548ST · PMID 28459336
• Grasselli G, Calfee CS, Camporota L, et al. ESICM guidelines on acute respiratory distress syndrome: definition, phenotyping and respiratory support strategies. Intensive Care Med. 2023;49(7):727-759. doi:10.1007/s00134-023-07050-7 · PMID 37326646
• Ferguson ND, Cook DJ, Guyatt GH, et al.; OSCILLATE Trial Investigators. High-frequency oscillation in early acute respiratory distress syndrome. N Engl J Med. 2013;368(9):795-805. doi:10.1056/NEJMoa1215554 · PMID 23339639
• Chand R, Swenson ER, Goldfarb DS. Sodium bicarbonate therapy for acute respiratory acidosis. Curr Opin Nephrol Hypertens. 2021;30(2):223-230. doi:10.1097/MNH.0000000000000687 · PMID 33395037

Tension, barotrauma, decompression

• Roberts DJ, Leigh-Smith S, Faris PD, et al. Clinical Presentation of Patients With Tension Pneumothorax: A Systematic Review. Ann Surg. 2015;261(6):1068-1078. doi:10.1097/SLA.0000000000001073 · PMID 25563887
• Anzueto A, Frutos-Vivar F, Esteban A, et al. Incidence, risk factors and outcome of barotrauma in mechanically ventilated patients. Intensive Care Med. 2004;30(4):612-619. doi:10.1007/s00134-004-2187-7 · PMID 14991090
• Laan DV, Vu TD, Thiels CA, et al. Chest wall thickness and decompression failure: A systematic review and meta-analysis comparing anatomic locations in needle thoracostomy. Injury. 2016;47(4):797-804. doi:10.1016/j.injury.2015.11.045 · PMID 26724173

Rescue strategies

• Anantham D, Jagadesan R, Tiew PE. Clinical review: Independent lung ventilation in critical care. Crit Care. 2005;9(6):594-600. doi:10.1186/cc3827 · PMID 16356244
• Berg S, Bittner EA, Berra L, Kacmarek RM, Sonny A. Independent lung ventilation: Implementation strategies and review of literature. World J Crit Care Med. 2019;8(4):49-58. doi:10.5492/wjccm.v8.i4.49 · PMID 31667133
• Ficial B, Whebell S, Taylor D, Fernández-Garda R, Okiror L, Meadows CIS. Bronchoscopic Endobronchial Valve Therapy for Persistent Air Leaks in COVID-19 Patients Requiring Veno-Venous Extracorporeal Membrane Oxygenation. J Clin Med. 2023;12(4):1348. doi:10.3390/jcm12041348 · PMID 36835885