Introduction Persistent air leaks (PAL) is the most frequent post-operative complication in Thoracic Surgery, leading to a longer hospital stay and an increase in patient morbidity. We present a prospective study conducted in the Dr. Josep Trueta University Hospital in Gerona, involving a portable chest drainage system (PCDS) connected to a pleural drainage which allowed air leaks to be treated ambulatorily. Our aim is to demonstrate that by using this system hospital stay is reduced without increasing post-operative morbidity, and improves the quality of life of the patient. Material and methods The Thoracic Surgery Department of Gerona Hospital collected the data on 33 patients with PAL in the post-surgical period and who were treated ambulatorily with a PCDS. Post-operative complications were recorded, along with the mean days of ambulatory treatment with the PCDS and the hospital days saved. Results The mean hospital stay of the 33 patients was 7.03 days. The mean number of days that the 33 patients were treated ambulatorily with the PCDS was 9.33 days. It was calculated that there was a saving of 308 hospital days. The ambulatory treatment of PAL did not increase post-operative morbidity. Conclusions The clinical results and the management of the PCDS support the treatment of this problem in patients who do not have any other causes to remain in hospital. The study shows a saving in a considerable number of hospital days stay, with no increase in patient morbidity. All the patients preferred this system to hospital admission.