Is povidone iodine (antiseptic solution) effective for pleurodesis?

Povidone-Iodine for Pleurodesis: Effective Alternative to Talc

Povidone-iodine is an effective and safe sclerosing agent for pleurodesis in malignant pleural effusions, achieving success rates of 88-98% that are comparable to talc (90-93%), with excellent tolerability and significantly lower cost than bleomycin. 1

Evidence Quality and Guideline Position

The major Western guidelines (British Thoracic Society, American Thoracic Society, European Respiratory Society/EACTS) do not include povidone-iodine in their primary recommendations, listing only talc (90-93% success), bleomycin (61% success), and doxycycline (76-85% success) as established options. 1 However, this omission reflects limited use in the UK and US rather than lack of efficacy, as povidone-iodine demonstrates comparable effectiveness to talc in clinical studies. 1

Efficacy Profile

• Complete response rates range from 82-90% across multiple studies, with one meta-analysis showing 88-98% success comparable to talc's 90-93%. 1, 2
• A prospective randomized controlled trial comparing povidone-iodine pleurodesis through thoracostomy tube versus thoracoscopic talc poudrage in 42 breast cancer patients showed no significant difference in recurrence rates (15% vs 9%, p=ns). 3
• In a direct comparison study of 52 patients, povidone-iodine achieved complete response in 86% (24/28 patients) versus talc's 79% (19/24 patients), with similar partial response and failure rates. 4
• A tertiary hospital study of 38 consecutive patients achieved 89.5% complete response with no recurrence during mean follow-up of 10.2 months. 5

Administration Protocol

• Insert a small-bore intercostal catheter (10-14F) and drain pleural fluid completely to ensure full lung re-expansion. 1
• Confirm complete lung expansion with chest radiograph before instillation. 1
• Instill 20 mL of 10% povidone-iodine solution (diluted in 80 mL normal saline to make 100 mL total volume) through the chest tube. 4, 5
• Clamp the chest tube for 1-2 hours after instillation. 4
• Patient rotation during the clamping period is not definitively established for povidone-iodine, though rotation is not necessary for tetracycline-class agents. 1
• Reconnect to suction after unclamping and remove chest tube when 24-hour drainage is less than 100-150 mL. 1

Safety Profile and Side Effects

• Povidone-iodine demonstrates excellent tolerability with no risk of acute respiratory failure, unlike talc which carries a small (<1%) risk of ARDS. 1
• Chest pain during instillation occurs in 7.9-26.9% of patients, which is lower than talc (18% requiring post-procedure analgesia). 5, 6, 3
• Fever occurs in approximately 5-13% of patients, comparable to other sclerosing agents. 4, 3
• Thyroid and renal function changes are not clinically significant, despite theoretical concerns about iodine absorption. 6
• No deaths occurred in the peri-pleurodesis period across multiple studies. 4, 5

Clinical Advantages Over Standard Agents

• Significantly lower cost than bleomycin while achieving superior success rates (90.6% vs 61%). 1, 7
• Readily available and does not require specialized handling like cytotoxic agents (bleomycin). 4, 5
• Can be administered as a bedside procedure through thoracostomy tube, avoiding need for thoracoscopy. 3
• Shorter post-procedure hospital stay compared to thoracoscopic talc poudrage (mean difference significant at p=0.009). 3
• Can be repeated if necessary without increased toxicity concerns. 3

When to Choose Povidone-Iodine

Consider povidone-iodine as first-line when:

• Talc is unavailable or cost is prohibitive. 1
• Bedside pleurodesis through small-bore catheter is preferred over thoracoscopy. 3
• Patient has significant comorbidities that increase risk with talc-related ARDS. 1
• Resource-constrained settings where cost-effectiveness is paramount. 4, 5

Talc remains superior as first-line when:

• Thoracoscopy is planned for diagnostic purposes (can perform talc poudrage simultaneously). 8
• Maximum possible success rate is critical and cost is not limiting. 1
• Extensive guideline support and institutional familiarity favor talc use. 1

Critical Contraindications and Pitfalls

• Never attempt pleurodesis without confirming complete lung re-expansion, as trapped lung or bronchial obstruction will result in treatment failure. 8, 1
• Avoid in patients with known iodine hypersensitivity (use alternative agent). 9
• Do not use in patients with active thyroid disease without endocrine consultation, though clinical thyroid dysfunction is rare. 6
• Ensure adequate analgesia before instillation, as 26.9% of patients experience significant chest pain. 6

Management of Treatment Failure

If povidone-iodine pleurodesis fails (recurrence of symptomatic effusion):

• Repeat instillation with same agent is safe and can be effective. 3
• Consider thoracoscopic talc poudrage as second-line option. 1
• Indwelling pleural catheter is preferred for patients with trapped lung or multiple failed attempts. 1