One-lung ventilation with intentional closure of the nonventilated lumen in a patient with giant pulmonary bullae undergoing laparoscopic anterior resection: a case report

Introduction

Background

Giant bullae are generally defined as air spaces occupying more than one-third of the hemithorax and are most commonly associated with advanced chronic obstructive pulmonary disease (COPD) and emphysematous changes (1,2). Although these lesions may remain asymptomatic for long periods, they pose significant risks during anesthesia and surgery because positive pressure ventilation (PPV) may promote further expansion or rupture of the fragile bullous wall, potentially resulting in life-threatening complications such as tension pneumothorax and circulatory collapse (2-5).

These challenges are amplified during laparoscopic colorectal surgery. Carbon dioxide (CO₂) pneumoperitoneum and Trendelenburg positioning can reduce respiratory system compliance, predominantly through reduced chest wall compliance and cephalad displacement of the diaphragm, thereby increasing measured airway pressure and the ventilatory demand for CO₂ elimination. Increased airway pressure in this setting reflects the combined mechanics of the lung and chest wall and should not be interpreted as a direct surrogate for transpulmonary pressure or bulla wall stress. In patients with giant bullae, anesthetic management, therefore, requires maintaining adequate gas exchange while minimizing PPV exposure, dynamic hyperinflation, and potential bullous overdistension (3,4). Although preservation of spontaneous respiration may theoretically reduce exposure to PPV-related risk, it is generally impractical for laparoscopic colorectal procedures and may not provide sufficient ventilation during pneumoperitoneum. Therefore, controlled ventilation under general anesthesia is often unavoidable and must be carefully adjusted (6).

Rationale and knowledge gap

Clear guidelines for the anesthetic management of patients with giant bullae undergoing laparoscopic nonthoracic surgery are lacking. Lung isolation devices, such as double-lumen tubes (DLTs) and bronchial blockers (BBs), may reduce ventilation-related stress on the affected lung (2-5). In conventional one-lung ventilation (OLV) with a DLT, the lumen of the nonventilated lung is typically left open to ambient air to facilitate lung collapse. However, previous reports have described spontaneous hyperinflation of a giant pulmonary bulla in the nonventilated lung during laparoscopic surgery when the lumen was left open to the atmosphere. This observation suggests that, in selected patients, ambient air entry into the nonventilated lung may contribute to progressive bullous expansion.

In the present case, we initially attempted OLV using a DLT while keeping the nonventilated lumen closed as a protective measure intended to minimize air entry into the bullous lung. Reports describing this approach during nonthoracic laparoscopic surgery are scarce. At the same time, OLV may be difficult to sustain during prolonged laparoscopy because the procedure increases ventilatory demand while limiting CO₂ elimination, thereby predisposing patients to hypercapnia and acidosis (7). Nevertheless, initial DLT placement may offer practical advantages by allowing flexible transition between OLV and two-lung ventilation (TLV) and independent access to each lung if rescue ventilation or suctioning became necessary (8).

Objective

Through this case of an elderly patient with a giant bulla in the right lung undergoing laparoscopic anterior resection, we describe the rationale for attempting OLV with closure of the nonventilated lumen, the subsequent ventilatory limitations encountered during prolonged laparoscopic surgery, and the need for conversion to TLV. This case highlights both the potential utility and the important limitations of this strategy in this clinical scenario. We present this article in accordance with the CARE reporting checklist (available at https://acr.amegroups.com/article/view/10.21037/acr-2026-0078/rc).

Case presentation

An 86-year-old male patient (154.7 cm, 34.7 kg, ideal body weight 52 kg) was scheduled for laparoscopic anterior resection for sigmoid colon cancer. Three weeks earlier, he had undergone endovascular aneurysm repair for bilateral iliac artery aneurysms. Preoperative chest X-ray and computed tomography performed at that time revealed a giant bulla measuring approximately 17.5 cm in maximal diameter, occupying the right mid-to-lower lung fields, and compressing the adjacent right lung parenchyma (Figure 1). Pulmonary function testing showed forced vital capacity (FVC) of 2.64 L, a forced expiratory volume in 1 second (FEV₁) of 1.6 L, and an FEV₁/FVC ratio of 60.68%, consistent with moderate obstructive ventilatory impairment. Owing to the risk associated with PPV, the previous vascular procedure had been performed under combined spinal-epidural anesthesia.

Figure 1 Preoperative chest computed tomography. (A) Axial and (B) coronal images showing a giant bulla occupying most of the right middle and lower lung fields without significant mediastinal shift. The remaining right upper lobe and the left lung were relatively preserved.

The patient had a history of hypertension, which was controlled with angiotensin receptor blocker and calcium-channel blockers. Transthoracic echocardiography showed preserved left ventricular systolic function (ejection fraction, 60%), mild mitral regurgitation, tricuspid regurgitation, pulmonary regurgitation, mild-to-moderate aortic regurgitation, and a small pericardial effusion measuring 0.37 cm without other significant abnormalities. Because rupture of the giant bulla could result in catastrophic complications such as tension pneumothorax, the anesthetic plan prioritized minimizing excessive positive pressure delivery to the right lung. After discussion with a thoracic surgeon, no prophylactic intervention for the bulla was performed because the patient had remained asymptomatic for a long time. However, the thoracic surgery team remained available for immediate chest tube insertion if unexpected rupture occurred.

General anesthesia was induced with propofol 40 mg and remifentanil at an effect-site concentration (Ce) of 3 ng/mL. Rocuronium 40 mg was administered, and tracheal intubation was performed with a left-sided 37-Fr DLT (Human-broncho). Anesthesia was maintained with sevoflurane initially set at 2 vol%, and subsequently adjusted according to the bispectral index. Remifentanil was titrated to an effect-site concentration of 1–5 ng/mL according to hemodynamic response. OLV was initiated immediately after induction, with ventilation delivered only to the left lung. The lumen connected to the nonventilated right lung was clamped, and the bronchoscopy port was kept closed to prevent exposure of the lumen to ambient air. A radial arterial catheter was inserted for serial arterial blood gas analysis (ABGA) to monitor oxygenation and CO₂ retention.

Ventilation was delivered in pressure-controlled ventilation-volume guaranteed (PCV-VG) mode with target tidal volumes of 250–300 mL, and peak inspiratory pressure (PIP) was kept at or below 18 cmH₂O. Plateau pressure and driving pressure were not recorded because an inspiratory-hold maneuver was not performed during PCV-VG ventilation (9,10). During maintenance of anesthesia, FiO₂ was maintained at 0.5, and the inspiratory/expiratory ratio was adjusted between 1:2 and 1:2.5 to maintain adequate expiratory time. External PEEP was not applied during either OLV or TLV. Pneumoperitoneum pressure was kept as low as surgical exposure allowed and remained below 12 mmHg. Oxygenation remained acceptable during OLV; however, CO₂ retention progressively worsened during the laparoscopic procedure. Two hours after initiation of OLV, ABGA showed a pH of 7.142 and PaCO₂ of 65.8 mmHg, necessitating conversion to TLV. After conversion to TLV, PCV-VG ventilation was continued using the same low-tidal volume, pressure-limited approach, with respiratory rate adjusted according to end-tidal CO₂ and serial ABGA findings, as summarized in Table 1. One hour later, immediately after the removal of the laparoscope and cessation of CO₂ insufflation, ABGA showed pH of 7.154 and PaCO₂ of 58.5 mmHg, end-tidal CO₂ values gradually improved (Table 1).

Before emergence from anesthesia, chest radiography showed no pneumothorax and no major interval change in the giant bulla (Figure 2). After reversal of neuromuscular blockade with sugammadex and recovery of spontaneous respiration, the patient was extubated uneventfully. No postoperative pneumonia or other clinically significant respiratory complication was documented. The Institutional Review Board of Kyungpook National University Chilgok Hospital in Daegu, Republic of Korea, granted an exemption from ethical approval for this case (No. KNUCH 2025-10-007) because the clinical data were deidentified. The patient provided informed consent for the publication of this case report and accompanying images. A copy of the written consent is available for review by the editorial office of this journal. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration and its subsequent amendments.

Figure 2 Perioperaive chest radiographs. (A) Preoperative chest radiograph showing a giant bulla in the right middle and lower lung fields. (B) Postoperative chest radiograph obtained before tracheal extubation showing no significant interval changes and no evidence of pneumothorax.

Discussion

This case illustrates a practical trade-off in the anesthetic management of patients with giant bulla undergoing prolonged laparoscopic surgery. In this setting, initial priority was to minimize potentially avoidable distension of bullous lung while maintaining adequate gas exchange during CO₂ pneumoperitoneum. On that basis, we chose OLV using a DLT and kept the nonventilated lumen closed. This approach should not be interpreted as an established protective technique, but rather as a rational risk-reduction strategy based on the concern that both direct positive pressure delivery and ambient air entrainment could further distend the diseased lung.

In patients with giant bullae, the anesthetic strategy should be individualized according to the location and extent of bullous lesion, the expected duration of surgery, and patient’s underlying pulmonary reserve. Various anesthetic techniques for patients with bullae have been reported, including regional anesthesia with the preservation of spontaneous respiration, maintenance of spontaneous breathing under general anesthesia with inhalational agents, and controlled ventilation using lung isolation devices such as BBs or DLTs (2,4,5). When feasible, spontaneous respiration may reduce exposure to PPV. However, this approach is often impractical for laparoscopic colorectal surgery and may provide insufficient ventilation during CO₂ pneumoperitoneum (6). When controlled ventilation is required, careful adjustment of tidal volume, airway pressure, respiratory rate, and expiratory time is essential to maintain gas exchange while avoiding dynamic hyperinflation and excessive airway pressure.

In the present case, the OLV using a DLT was initially selected to avoid direct positive pressure delivery to the right lung, where the giant bulla was located. The rationale for keeping the nonventilated lumen closed was to limit ambient air entrainment into the right lung (11-13). In conventional OLV with a DLT, the lumen of the nonventilated lung is usually left open to the atmosphere to facilitate lung collapse. However, previous reports have described spontaneous hyperinflation of a giant pulmonary bulla in the nonventilated lung during laparoscopic surgery when the lumen was left open to ambient air (2). In addition, studies investigating lung collapse during OLV have shown that, in a closed chest without pleural opening, ambient air may enter the nonventilated lung through an open lumen rather than simply facilitating passive collapse (11-14). Proposed mechanisms include mediastinal displacement caused by ventilation of the dependent lung, tidal gas movement within the nonventilated lung, and negative pressure generated by gas absorption into the pulmonary circulation (11,12). This issue may be particularly relevant in patients with emphysematous lungs or giant bullae. Reduced elastic recoil and expiratory flow limitation may impair the initial phase of lung collapse (15), while destruction of the alveolar-capillary interface within bullae limits gas absorption into the bloodstream, thereby impairing the later phase of collapse (16). Therefore, leaving the lumen open to ambient air could theoretically allow air entrainment and persistent distension of the diseased lung. At the same time, closure of the nonventilated lumen has potential disadvantages that should be recognized. If gas enters the isolated lung through mechanisms other than ambient air entrainment, maintaining the lumen in a closed state could theoretically impede gas egress and promote gas trapping. In addition, a clamped lumen reduces immediate access for suctioning, oxygen insufflation, or CPAP to the nonventilated lung. Although these rescue maneuvers remain possible with a DLT, the lumen must first be reopened and the ventilatory plan modified, which may not be readily feasible during ongoing laparoscopy.

Therefore, we kept the nonventilated lumen closed as an initial risk-reduction measure intended to limit ambient air entry into the right lung, while recognizing these trade-offs. However, this physiological rationale should be interpreted cautiously. In the present case, bulla volume, regional lung volume, and pressure within the nonventilated lung were not directly measured. Therefore, the absence of bulla rupture should be regarded as a favorable clinical observation, rather than definitive evidence that nonventilated lumen closure prevented bulla overdistension or rupture.

The major limitation encountered in this case was the limited sustainability of the approach during the prolonged laparoscopy. Progressive CO₂ retention and acidosis eventually necessitated conversion from OLV to TLV. This deterioration was likely multifactorial, reflecting the reduced ventilatory capacity inherent to OLV together with prolonged CO₂ pneumoperitoneum, Trendelenburg positioning, decreased respiratory system compliance, increased CO₂ absorption, and underlying COPD-related or emphysematous physiology (7,17-20). Whether nonventilated lumen closure itself contributed to the hypercapnia cannot be determined from a single case. An additional limitation related to pressure interpretation during ventilation. In this case, OLV was performed in PCV-VG mode, which automatically adjusts inspiratory pressure to achieve the target tidal volume with the lowest feasible pressure. However, in a patient with COPD, the displayed PIP in a pressure-controlled mode should not be assumed to represent plateau pressure (9,10,21). Plateau pressure and driving pressure require zero end-inspiratory flow or an inspiratory-hold maneuver; In the presence of increased airway resistance and/or short inspiratory time, plateau pressure may be lower than the displayed PIP. Because an inspiratory-hold maneuver was not performed, plateau pressure and driving pressure were not recorded, and reliance on PIP alone should be considered a limitation of this report.

Alternative approaches may be considered in similar cases. Selective lobar blockade using a BB may allow ventilation of relatively preserved lobes while isolating the most severely affected region, thereby potentially improving gas exchange compared with complete exclusion of one lung (22,23). In this patient, preoperative imaging suggested predominant involvement of the right middle and lower lung fields, while partial extension into adjacent lobes, including the right upper lobe, could not be excluded (24). In addition, BBs are susceptible to malposition, incomplete occlusion, intraoperative displacement, and difficulty in maintaining stable blockade during prolonged surgery (22). Considering these factors, initial placement of a DLT was chosen in this case to provide reliable lung isolation, independent access to each lung, and flexibility to transition between OLV and TLV when necessary.

In summary, this case suggests that OLV with closure of the nonventilated lumen may be a reasonable initial strategy in a patient with giant bullae undergoing laparoscopic surgery, particularly when avoidance of further inflation of the diseased lung is a major concern. However, it should not be regarded as a definitively protective or universally successful strategy. During prolonged laparoscopic surgery, clinicians should anticipate progressive hypercapnia and acidosis, monitor gas exchange closely, and maintain a low threshold for changing the ventilator strategy, including conversion to TLV.

Conclusions

In patients with giant bullae undergoing laparoscopic surgery, OLV using a DLT with the nonventilated lumen kept closed may be considered as a reasonable initial risk-reduction strategy when further inflation of the diseased lung is a major concern. However, this approach should not be regarded as definitively protective, and its feasibility may be limited during prolonged CO₂ pneumoperitoneum by progressive hypercapnia and acidosis. Careful monitoring of gas exchange and readiness to convert to TLV are essential when adequate ventilation cannot be sustained.

Acknowledgments

None.

Footnote

Reporting Checklist: The authors have completed the CARE reporting checklist. Available at https://acr.amegroups.com/article/view/10.21037/acr-2026-0078/rc

Peer Review File: Available at https://acr.amegroups.com/article/view/10.21037/acr-2026-0078/prf

Funding: None.

Conflicts of Interest: Both authors have completed the ICMJE uniform disclosure form (available at https://acr.amegroups.com/article/view/10.21037/acr-2026-0078/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration and its subsequent amendments. The Institutional Review Board of Kyungpook National University Chilgok Hospital in Daegu, Republic of Korea, granted an exemption from ethical approval for this case (No. KNUCH 2025-10-007) because the clinical data were deidentified. The patient provided informed consent for the publication of this case report and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Koratala A, Bhatti V. Look before you leap: a curious case of giant pulmonary bulla. BMJ Case Rep 2017;2017:bcr2017220058. [Crossref] [PubMed]
2. Mayahara T, Fukuoka R, Shimada N, et al. Spontaneous hyperinflation of a giant bulla of the non-ventilated lung during laparoscopic cholecystectomy under one-lung ventilation: a case report. JA Clin Rep 2022;8:62. [Crossref] [PubMed]
3. Huang W, Han R, Li L, et al. Surgery for giant emphysematous bullae: case report and a short literature review. J Thorac Dis 2014;6:E104-7. [Crossref] [PubMed]
4. Mottaghi K, Asadi S, Safari F, et al. Anesthesia management of bullous emphysema in patient candidate for craniotomy. Ann Anesth Crit Care 2016;1:1-3.
5. Saini V, Assu SM, Bhatia N, et al. Abdominal surgery in a patient with bullous emphysema: Anesthetic concerns. J Anaesthesiol Clin Pharmacol 2019;35:414-5. [Crossref] [PubMed]
6. Perrin M, Fletcher A. Laparoscopic abdominal surgery. Continuing Educ Anaesth Crit Care Pain 2004;4:107-10.
7. Zhang L, Sun Z, Chang J, et al. Effects of driving pressure-guided lung-protective ventilation strategy on respiratory mechanics, oxygenation, and postoperative pulmonary complications in patients undergoing minimally invasive esophagectomy: a randomized clinical trial. J Thorac Dis 2025;17:10308-23. [Crossref] [PubMed]
8. Patel M, Wilson A, Ong C. Double-lumen tubes and bronchial blockers. BJA Educ 2023;23:416-24. [Crossref] [PubMed]
9. Hess DR. Respiratory mechanics in mechanically ventilated patients. Respir Care 2014;59:1773-94. [Crossref] [PubMed]
10. Sosio S, Bellani G. Plateau pressure during pressure control ventilation. AboutOpen 2019;6:76-7.
11. Pfitzner J, Peacock MJ, McAleer PT. Gas movement in the nonventilated lung at the onset of single-lung ventilation for video-assisted thoracoscopy. Anaesthesia 1999;54:437-43. [Crossref] [PubMed]
12. Somma J, Couture ÉJ, Pelletier S, et al. Non-ventilated lung deflation during one-lung ventilation with a double-lumen endotracheal tube: a randomized-controlled trial of occluding the non-ventilated endobronchial lumen before pleural opening. Can J Anaesth 2021;68:801-11. [Crossref] [PubMed]
13. Zhang Y, Yan W, Fan Z, et al. Preemptive one lung ventilation enhances lung collapse during thoracoscopic surgery: A randomized controlled trial. Thorac Cancer 2019;10:1448-52. [Crossref] [PubMed]
14. Li Q, Zhang X, Wu J, et al. Two-minute disconnection technique with a double-lumen tube to speed the collapse of the non-ventilated lung for one-lung ventilation in thoracoscopic surgery. BMC Anesthesiol 2017;17:80. [Crossref] [PubMed]
15. Gagnon P, Guenette JA, Langer D, et al. Pathogenesis of hyperinflation in chronic obstructive pulmonary disease. Int J Chron Obstruct Pulmon Dis 2014;9:187-201. [Crossref] [PubMed]
16. Thurlbeck WM. Pathology of chronic airflow obstruction. Chest 1990;97:6S-10S.
17. Kendall AP, Bhatt S, Oh TE. Pulmonary consequences of carbon dioxide insufflation for laparoscopic cholecystectomies. Anaesthesia 1995;50:286-9. [Crossref] [PubMed]
18. Şentürk M, Slinger P, Cohen E. Intraoperative mechanical ventilation strategies for one-lung ventilation. Best Pract Res Clin Anaesthesiol 2015;29:357-69. [Crossref] [PubMed]
19. Jo YY, Kwak HJ. What is the proper ventilation strategy during laparoscopic surgery? Korean J Anesthesiol 2017;70:596-600. [Crossref] [PubMed]
20. Hsieh CH. Laparoscopic cholecystectomy for patients with chronic obstructive pulmonary disease. J Laparoendosc Adv Surg Tech A 2003;13:5-9. [Crossref] [PubMed]
21. Ahmed SM, Athar M. Mechanical ventilation in patients with chronic obstructive pulmonary disease and bronchial asthma. Indian J Anaesth 2015;59:589-98. [Crossref] [PubMed]
22. Campos JH. Update on selective lobar blockade during pulmonary resections. Curr Opin Anaesthesiol 2009;22:18-22. [Crossref] [PubMed]
23. Ren Y, Lyu Y, Yu Y, et al. Selective right middle and lower lobar blockade for minimally invasive cardiac surgery: a prospective, single-center, randomized controlled study. Ann Transl Med 2021;9:254. [Crossref] [PubMed]
24. Koster TD, Slebos DJ. The fissure: interlobar collateral ventilation and implications for endoscopic therapy in emphysema. Int J Chron Obstruct Pulmon Dis 2016;11:765-73. [Crossref] [PubMed]