Intraoperative pneumothorax during arthroscopic rotator cuff repair: a case report and literature review

Abstract

Introduction and importance:

Arthroscopic rotator cuff repair is generally safe, but intraoperative pneumothorax is a rare, potentially fatal complication with poorly defined mechanisms and limited clinical guidance. This report aims to clarify the clinical course, mechanisms, and management of this complication, highlighting novel intraoperative warning signs and actionable prevention strategies.

Case presentation:

A 50-year-old female with a full-thickness right supraspinatus tear underwent arthroscopic repair in the left lateral position under general anesthesia with an interscalene nerve block. Preoperative pulmonary function and chest imaging were normal. Intraoperatively, abrupt oxygen desaturation (SpO₂ to 79%), reduced tidal volume (500 → 332 mL), and elevated inspiratory pressure (9→18 cmH₂O) developed near the completion of the procedure. Chest radiography confirmed a right pneumothorax with 70% lung collapse. A closed thoracic drain was emergently placed upon completion of the surgery. The patient recovered uneventfully, with drain removal on postoperative day 2 and discharge on day 7. Three-month follow-up confirmed full rotator cuff healing and normal pulmonary status.

Clinical discussion:

Intraoperative pneumothorax in shoulder arthroscopy arises from a multifactorial mechanism: barotrauma from high pump pressure, pleural micro-perforation, and anesthetic-related airway pressure elevation. This case offers novel insights, specifically identifying early desaturation and pressure spikes as sentinel signs and demonstrating the feasibility of safely completing surgery followed by immediate thoracic decompression. A structured literature review shows an incidence of 0.03–0.1%, with most cases underreported.

Conclusion:

Intraoperative pneumothorax is a rare but life-threatening complication of shoulder arthroscopy. Surgeons and anesthesiologists must recognize early ventilatory changes, adopt low-pressure arthroscopy protocols, and maintain a high index of clinical suspicion. This case provides a mechanistic framework and an evidence-based management pathway to improve patient safety.

Introduction

Shoulder arthroscopy is the standard of care for rotator cuff tears, instability, and impingement, providing reduced pain, faster recovery, and superior functional outcomes compared with open surgery^[1,2^]. Notwithstanding its favorable safety profile, rare but severe complications include neurovascular injury, fluid extravasation, and intraoperative pneumothorax^[3,4^]. Pneumothorax – air accumulation in the pleural cavity – can cause acute respiratory distress and requires urgent intervention, yet its incidence in shoulder arthroscopy is estimated at only 0.03–0.1%, although the majority of cases are believed to be underreported^[4,5^].

HIGHLIGHTS

• Pneumothorax is a rare but potentially fatal complication of shoulder arthroscopy, with a low reported incidence, and it is underreported in the existing literature. Clinical understanding of its pathogenesis and mechanisms remains insufficient, despite the growing popularity of shoulder arthroscopic techniques. This case report fills a gap in the clinical understanding of this rare complication, highlighting that, with the increasing application of shoulder arthroscopy, heightened clinician awareness of pneumothorax is essential. Proactive risk identification, timely diagnosis, and standardized intervention can significantly improve patient outcomes, reduce postoperative morbidity, and optimize the safety of shoulder arthroscopic procedures. Continuous education and research in shoulder surgery are needed to further refine prevention and management strategies for such rare complications.

The pathogenesis of intraoperative pneumothorax remains poorly understood, with proposed mechanisms including high-pressure arthroscopy pump-induced pleural breach, barotrauma, interscalene block-related pleural injury, and patient-specific anatomic variations^[6,7^]. Existing case reports lack structured analysis of mechanisms, intraoperative warning signs, and standardized prevention strategies^[8,9^].

This case report adheres to the CARE (Case Reports) guidelines, presenting a detailed clinical timeline, intraoperative parameters, and imaging findings^[10^]. We aim to: (1) describe a rare case of intraoperative pneumothorax during rotator cuff repair; (2) propose a focused mechanistic hypothesis supported by existing literature; (3) compare this case with previously reported cases; (4) highlight novel intraoperative indicators; and (5) provide evidence-based prevention and management recommendations to enhance clinical awareness and patient safety.

Case presentation

A 50-year-old woman presented with a 6-month history of right shoulder pain and weakness and was diagnosed with a full-thickness supraspinatus tear on magnetic resonance imaging (MRI) (Fig. 1A). She had no history of smoking, pulmonary disease, or chest trauma. Preoperative chest radiography and pulmonary function tests were normal (Fig. 1B).

Figure 1.

(A) Coronal MRI showing a full-thickness tear of the right supraspinatus tendon. (B) Preoperative chest radiograph with normal lung fields. (C) Intraoperative chest radiograph demonstrating a right pneumothorax with 70% lung collapse (yellow arrow indicates the pleural line). (D) Post-drainage chest radiograph showing near-complete re-expansion of the right lung. (E) Pre-drain removal CT scan with minimal residual apical pneumothorax. (F) Three-month postoperative MRI confirming an intact supraspinatus tendon. (G) Three-month follow-up chest CT with normal right lung parenchyma.

Perioperative details

Positioning: The patient was placed in the left lateral decubitus position. Anesthesia: General endotracheal anesthesia (volume-controlled ventilation; tidal volume 6–8 mL/kg; positive end-expiratory pressure 5 cmH₂O; FiO₂ 40%) was administered, along with an ultrasound-guided interscalene nerve block (20 mL 0.5% ropivacaine) given preoperatively. Arthroscopy: A 30-degree arthroscope was used, with posterior, anterior, and lateral portals, and pump pressure was maintained at 60 mmHg.

Intraoperative course and timeline

0–80 min: Uneventful surgery; vital signs stable (BP 90–100/60–70 mmHg; SpO₂ 98–100%; EtCO₂ 35–40 mmHg; inspiratory pressure 9 cmH₂O). 82 min (near completion): Abrupt SpO₂ drop to 79%; tidal volume reduced to 332 mL; inspiratory pressure increased to 18 cm H₂O. FiO₂ increased to 100%; SpO₂ slowly increased to 89%, indicating an inadequate response. Surgery was expedited and completed; the patient was placed supine for urgent imaging. Bedside ultrasound findings were negative for pericardial/pleural fluid or pneumothorax (limited sensitivity in the supine position). Chest radiography confirmed a right pneumothorax with 70% lung collapse (Fig. 1C). A 12 F chest drain was inserted in the right second intercostal space, resulting in the immediate release of air. SpO₂ was restored to 98%; tidal volume normalized to 500 mL; inspiratory pressure to 10 cmH₂O.

Postoperative course

• The patient was admitted to the intensive care unit for 18 hours; repeat chest radiography showed near-complete lung re-expansion (Fig. 1D). The patient was extubated upon becoming alert and subsequently transferred to the general ward. The chest drain was removed on postoperative day 2, following a repeat computed tomography (CT) scan that revealed minimal residual air (Fig. 1E). The patient was discharged on postoperative day 7 without respiratory symptoms. At the 3-month follow-up, MRI confirmed an intact supraspinatus tendon (Fig. 1F), chest CT results were normal (Fig. 1G), and the patient had achieved full recovery of shoulder function.

Discussion

Intraoperative pneumothorax during shoulder arthroscopy is rare, with an incidence of 0.03–0.1% in large series^[4,5^]. Most published cases involve delayed postoperative pneumothorax (24–48 hours postoperatively), while intraoperative onset is exceedingly rare (only eight cases reported since 2020)^[6,8,9^]. Compared to prior reports, this case offers three novel insights: first, early ventilatory warning signs characterized by abrupt desaturation and elevated inspiratory pressure; second, patients remain at risk even with low pump pressures (60 mmHg), which challenges the assumption that low pressure eliminates this risk; third, safe completion of the surgery was achieved through rapid procedure termination and immediate decompression, which prevented the development of tension pneumothorax.

We propose a triple-mechanism hypothesis for intraoperative pneumothorax in this case, supported by the literature: (1) Barotrauma and fluid extravasation, where, even at 60 mmHg, arthroscopic fluid can dissect through the subclavian soft tissue into the pleural space, causing pleural microtears and air leakage^[7^]. (2) Interscalene block-related pleural irritation occurs when the proximity of the needle to the apical pleura during block placement weakens pleural integrity, predisposing the tissue to rupture under positive-pressure ventilation^[6^]. (3) With respect to anesthetic airway pressure, intraoperative positive-pressure ventilation (with elevated inspiratory pressure greater than 18 cm H₂O) increases intrathoracic pressure, thereby expanding pleural microtears into an overt pneumothorax^[4^].

In this instance, the ultrasound result was negative due to the patient’s supine position (ultrasound sensitivity for pneumothorax drops from 95% [upright] to 60% [supine]).^[11^] Chest radiography demonstrates superior sensitivity for intraoperative diagnosis, with a 10-minute turnaround critical for timely intervention. In clinical practice, the diagnosis of pneumothorax relies on symptoms, physical findings, and imaging. Intraoperatively, anesthetized patients cannot report symptoms, making imaging critical for timely, accurate diagnosis. While CT is considered the gold standard for imaging pneumothorax, chest radiography, as the initial study, offers high sensitivity.

Management of pneumothorax depends on the degree of its severity. For patients who are asymptomatic or have mild symptoms, supportive care consisting of observation and supplemental oxygen is often appropriate. Severe cases may require invasive treatments such as chest tube insertion or surgery to facilitate drainage^[4,12^]. The clinical condition of the patient and size of the pneumothorax guide decision-making. Preventive strategies can be taken to minimize the risk of pneumothorax in shoulder arthroscopy. To minimize the risk of intraoperative pneumothorax, we should: (1) monitor inspiratory pressure and tidal volume, and immediately investigate any abrupt changes; (2) maintain pump pressure ≤50 mmHg in shoulder arthroscopy^[13^]; (3) use ultrasound guidance for interscalene blocks to avoid deep needle insertion near the apex; (4) screen for smoking history, bullous lung disease, or thoracic anomalies; and (5) surgeons and anesthesiologists must alert each other to ventilatory changes.

Clinical Takeaways: Intraoperative pneumothorax is rare but life-threatening; ventilatory changes are early warning signs. The mechanisms of intraoperative pneumothorax are multifactorial and include barotrauma, pleural breach, and anesthetic factors. Low pump pressure does not eliminate risk; maintain a high clinical suspicion. CARE-compliant reporting improves understanding of rare complications and guides clinical practice.

Conclusion

Intraoperative pneumothorax during arthroscopic rotator cuff repair is a rare but potentially life-threatening complication. This case presents a structured mechanistic hypothesis, novel intraoperative warning signs, and evidence-based prevention strategies. Surgeons and anesthesiologists should collaborate to recognize early ventilatory changes, adopt low-pressure protocols, and prioritize patient safety. Further multicenter studies are warranted to validate these findings and refine risk-reduction guidelines.

Ethical approval

No ethical approval necessary.

Consent

Written informed consent was obtained from the patient for publication of this case report and accompanying images.

Sources of funding

This work was supported by the Science and Technology Plan of Jiangxi Provincial Health Commission (No. 202510455) and the Science and Technology Plan Project of Jiangxi Provincial Administration of Traditional Chinese Medicine (No. 2024B0364) and the Guiding Science and Technology Plan Project of Ganzhou City (No. 2025ZSFCE0283) and Doctoral Research Initiation Fund Project (No. QD202509) of The First Affiliated Hospital of Gannan Medical University.

Author contributions

Conceptualization: Y.L. and X.L.; Methodology: Y.L.; Investigation: Y.P.; Writing – original draft: Y.L.; Writing – review and editing: X.L.; Supervision: M.Z.; Funding acquisition: M.Z.

Conflicts of interest disclosure

The authors declare that they have no competing interests.

Research registration unique identifying number (UIN)

Our paper is a case report; no registration was done for it.

Guarantor

Not applicable.

Provenance and peer review

Not applicable.

Data availability statement

Data will be made available on request.