Long-term results after tetracycline pleurodesis in spontaneous pneumothorax.

From 1979 to 1988 483 patients were admitted with primary spontaneous pneumothorax. All patients underwent thoracoscopy to identify the cause of pneumothorax. Chemical pleurodesis with instillation of tetracycline was performed if cysts less than 2 cm in diameter were found. If larger cysts were identified the patient underwent thoracotomy. In 93 patients with cysts larger than 2 cm the recurrence rate after thoracotomy was 4%. In 390 patients treated with intrapleural instillation of tetracycline, the recurrence rate was 16%. Fifty percent of the recurrences occurred within 30 days. The cause of recurrence in 42 patients (69%) was cysts missed at the initial thoracoscopy. This study has demonstrated that thoracoscopy is a reliable and safe method for selection of patients for chemical pleurodesis. It is, however, necessary that the thoracoscopy is meticulous to avoid recurrence from missed cysts.