Current issues of ACP Journal Club are published in Annals of Internal Medicine


Therapeutics

Intrapleural tetracycline reduced recurrent pneumothorax

ACP J Club. 1991 Mar-April;114:47. doi:10.7326/ACPJC-1991-114-2-047


Source Citation

Light RW, O'Hara VS, Moritz TE, et al. Intrapleural tetracycline for the prevention of recurrent spontaneous pneumothorax. Results of a Department of Veterans Affairs Cooperative Study. JAMA. 1990; 264:2224-30.


Abstract

Objective

To determine the efficacy of intrapleural tetracycline for prevention of recurrence of pneumothorax in men with a spontaneous pneumothorax requiring tube thoracostomy.

Design

Randomized, unblinded, controlled trial with mean follow-up of 34.4 months in patients randomized to tetracycline and 29.1 months in control patients.

Setting

Department of Veterans Affairs medical centers in the United States.

Patients

Men were included if they had a spontaneous pneumothorax that required a tube thoracostomy. Patients were excluded if they had a traumatic or iatrogenic pneumothorax; an allergy to tetracycline; active pulmonary tuberculosis; previous injection of a chemical into the involved pleural space in an effort to create a chemical pleurodesis; a history of thoracotomy on the involved side; empyema; intrathoracic malignancy; failure of the lung to expand after tube placement; or if they could not be randomized within 72 hours of lung expansion. The average age of the patients was 54 years, and most had chronic obstructive pulmonary disease. 3 patients in the tetracycline group (n = 113) and 11 patients in the control group (n = 116) were not followed for the duration of the study.

Intervention

The treatment group received 1500 mg of tetracycline hydrochloride, brought to a total volume of 50 mL with saline, injected through a chest tube into the pleural space.

Main outcome measure

Rate of recurrent pneumothorax.

Main results

26 patients (25%) in the tetracycline group had a recurrence of pneumothorax compared with 44 patients (41%) in the control group (P < 0.02). {This absolute risk reduction of 16% means that 6 patients would need to be treated with intrapleural tetracycline (compared with placebo) to prevent 1 additional patient from having a recurrence; the relative risk reduction was 39%, CI 9% to 59%}.* This finding was confirmed by a survival analysis examining time to recurrent pneumothorax (P < 0.02). The beneficial effect of tetracycline was seen in the first 6 months after treatment. Of the patients randomized to tetracycline, 58% had severe chest pain. For 61% of these, use of analgesics did not relieve pain. The median duration of pain was 1.5 hours and only 5% experienced pain for more than 24 hours.

Conclusion

Treatment of men with spontaneous pneumothorax with intrapleural tetracycline resulted in a lower rate of recurrent pneumothorax than in the untreated controls.

Source of funding: Department of Veterans Affairs.

Address for article reprint: Dr. R.W. Light, Veterans Affairs Medical Center/ 151, 5901 E 7th St., Long Beach, CA 90822, USA.

*Numbers calculated from data in article.


Commentary

This is a well-designed clinical trial that confirms the findings of previous smaller, uncontrolled studies. Several laudatory aspects of the methods should be mentioned: The size of the study was determined by power calculations; details of eligible and ineligible patients were provided, allowing the reader to assess whether the results could be generalized to his or her own patients; details of the failure of therapy and of patients who could not be evaluated were included.

The data from the trial support the authors' conclusion that intrapleural tetracycline is effective in reducing recurrent pneumothorax. However, it should be noted that the patients were all men and that most had chronic obstructive lung disease (about 70% had an FEV1/FVC ratio < 0.70). Until further similarly well-designed studies show comparable results in younger patients free from pulmonary disease, thoracotomy with pleural ablation may still be the preferred choice for the practitioner.

The authors make a good case for the use of tetracycline as the sclerosing agent of choice. However, talc has also been shown to be effective (1). The difficulty of aerosolized talc administration may be overcome by thoracoscopy (2, 3), thereby avoiding the morbidity associated with thoracotomy and talc pleurodesis, but further studies are needed to validate this approach.

Praveen N. Mathur, MD
Indiana University Medical CenterIndianapolis, Indiana, USA


References

1. Viskum K, Lange P, Mortensen J. Long term sequelae after talc pleurodesis for spontaneous pneumothorax. Pneumologie. 1989;43:105-6.

2. Almind M, Lange P, Viskum K. Spontaneous pneumothorax: comparison of simple drainage, talc pleurodesis, and tetracycline pleurodesis. Thorax. 1989; 44:627-30.

3. Verschoof AC, Ten Velde GP, Greve LV. Thoracoscopic pleurodesis in the management of spontaneous pneumothorax. Respiration. 1988;53:197-200.