Introduction:

Limited data on comparing the clinical outcomes between different starting doses of tissue plasminogen activator(tPA) in pleural infection.

Aims and objectives:

To evaluate the therapeutic efficacy and complications between low(2.5mg or 5mg) and standard(10mg) starting doses of intrapleural tPA in pleural infection.

Methods:

Hospital records of patients with pleural infection who received intrapleural tPA from 2018 to 2022 were retrieved. The dosage of tPA, clinical response and complications were reviewed. The primary endpoint is the prevention of surgery with survival through the hospital stay. Secondary endpoints include complication rates, bleeding events.

Results:

41 patients(33 male, 80.5%) of median age 63(IQR 56-72) years were included, with 36(87.8%) pleural infection and 4(9.8%) tuberculous pleuritis. 13(31.7%), 3(7.3%) and 25(61.0%) patients received a starting dose of 2.5mg, 5mg and 10mg tPA respectively. A median of 5(IQR 3-6) injections were given, with 5 patients had dose escalation at the 5th(IQR 2-5) dose. Patients who survived without surgery(93.8% vs 88.0%, p=0.545), experienced any complications(43.8% vs 52.0%, p=0.606) and severe bleeding(25.0% vs 24.0%, p=0.942) were comparable between low and standard dose groups. When complications were matched with each course of tPA, they occurred less commonly when using 2.5mg than 10mg(21.4% vs 53.6%, p=0.047), while no significant difference in severe bleeding in both groups(7.1% vs 28.6%, p=0.230).

Conclusions:

Low dose tPA is an effective and safe alternative, with the advantage of flexibility in dose escalation during the course of treatment.