Outpatient Management of Primary Spontaneous Pneumothorax: Pigtail Catheter With Unidirectional Valve vs. Exsufflation, Randomized Prospective Study

This is a multicenter, randomized, open-label, parallel-group superiority trial. Eligible patients are adults (between 18 years old and 50 years old) presenting to the emergency department of a participating center with a large unilateral primary spontaneous pneumothorax. After information and written consent, patients are randomized on Day 0 to one of two arms :

* ambulatory management with pigtail catheter connected to one-way valve as previously published (Voisin F et al. Ann Emerg Med 2014; Sale A et al. Respir Med 2020) or
* manual aspiration as described in international guidelines.

Large pneumothorax is defined according to BTS, ACCP and/or French guidelines as a separation of ≥ 2 cm at the hilum, and/or ≥ 3 cm at the apex, and/or ≥ 2 cm over the whole height on an axillary view. Complete or near-complete re-expansion means a residual pneumothorax below these thresholds; otherwise the pneumothorax is considered persistent.

In both arms, failure is defined as hospitalization. In the manual aspiration arm, it also includes switching to the one-way valve arm (circuit reopened, valve connected), which is immediate (Day 0, Hour 0) if an aspirated volume of ≥ 2 L (40 syringes) is reached. The patient then receives usual care.

3\) Other data collected. All patients are seen on Day 2, Day 6 and, if needed, Day 4, with a standard pulmonology history and clinical examination. Pain and analgesic consumption are recorded daily from Day 1 to Day 6, together with adverse events. Pain is also assessed at catheter removal.

4\) Long-term follow-up. Patients are contacted at Months 3, 6, 9 and 12 to document pneumothorax recurrence and pleurodesis.

5\) Previous inclusion / Repeat episodes Patients already included in this study for a previous large PSP episode are not eligible.

• Fuhrman catheter insertion (Procedure): 8.5 French Fuhrman catheter insertion using the Seldinger technique, connected to a three-way stopcock and a one-way valve
• Three-way stopcock open (Procedure): Opening of the three-way stopcock on Day 0 to connect the Fuhrman catheter to the one-way valve
• Manual aspiration (Procedure): Manual aspiration through the Fuhrman catheter with a 50 mL syringe through the Fuhrman catheter on Day 0, followed by closure of the three-way stopcock (optional second aspiration).

Primary outcomes

• Rate of successful ambulatory management [Day 6]: Success is assessed for each patient at Day 6 and is defined as complete or near-complete lung re-expansion on the Day 6 chest X-ray, without hospitalization decided by the treating physician and, in the manual aspiration arm, without change of arm (reopening of the circuit with connection of the one-way valve). Failure may occur earlier than Day 6: on Day 0 (Hour 0, Hour 4 or Hour 8) or Day 2 in the manual aspiration arm, and on Day 4 in the one-way valve arm. A patient switched from manual aspiration to the one-way valve is a failure even if the lung is re-expanded on Day 6. Pneumothorax thresholds are defined in the Detailed Description and Eligibility part.

Secondary outcomes

• Comparison of pain intensity between the two arms [Day 0 to Day 6]: Pain intensity assessed on a Visual Analogue Scale (VAS) for pain intensity ranging from 0 (no pain) to 10 (worst pain imaginable), where higher scores indicate worse pain, at catheter insertion \[Day 0\], after each aspiration procedure (manual aspiration arm) \[Day 0\], at catheter removal, and daily from Day 1 to Day 6. Pain is compared between the manual aspiration arm and the one-way valve arm.
• Comparison of analgesic consumption between the two arms [Day 0 to Day 6]: Analgesic use at catheter insertion and daily from Day 1 to Day 6, recorded by WHO analgesic ladder step (step 1, 2 or 3). Consumption is compared between the manual aspiration arm and the one-way valve arm.
• Comparison of the cost of management between the two arms [Day 6]: Cost of each management strategy, including the estimated cost of hospitalization in case of early failure of manual aspiration. Costs are compared between the manual aspiration arm and the one-way valve arm.
• Comparison of pneumothorax recurrence between the two arms [Months 3, 6, 9 and 12]: Recurrence of pneumothorax assessed by telephone call or email at Months 3, 6, 9 and 12. Recurrence rates are compared between the manual aspiration arm and the one-way valve arm.

Sex: All, ages: 18 Years to 50 Years

* Inclusion Criteria :

  * Episode of large unilateral primary spontaneous pneumothorax according to British Thoracic Society (BTS), American College of Chest Physicians (ACCP) and/or French guidelines, defined as : a separation of ≥ 2 cm at the hilum, and/or ≥ 3 cm at the apex, and/or ≥ 2 cm over the whole height on an axillary view
  * Free and informed consent of the patient
* Exclusion Criteria :

  * Impossibility of ambulatory management, at the clinician's discretion
  * Inability to follow or understand the study procedures
  * Secondary pneumothorax, i.e. associated with an underlying chronic respiratory disease such as chronic obstructive pulmonary disease (COPD), emphysema, asthma, cystic fibrosis or pulmonary fibrosis
  * Non-spontaneous pneumothorax: traumatic or iatrogenic
  * Protected persons: adults under legal protection (judicial protection, curatorship or guardianship), persons deprived of liberty, pregnant women (self-reported), breastfeeding women, and minors