Criteria for Good Drainology™
The fundamentals in providing chest drainage therapy after cardiothoracic surgery or for therapeutic reasons have not changed over the past 30 years, but the biological and clinical knowledge, as well as technological advancements have extended new possibilities in treatment of patients who may require chest drainage and offers clinicians the opportunity to explore new ways of applying Drainology™.
As an orientation please find the following criteria for good Drainology™, which provide some basics of drainage management.
Indications for Chest Drain Insertion
Chest drains are sited in the pleural space after general thoracic procedure principally to evacuate excess air and fluid (pleural fluid, blood, chyle). The production of pleural fluid is normal and some bleeding can always be expected after surgery. The challenge on when to insert a drain is a balance between the decision of a) what can be safely tolerated and managed by the patient’s own physiology and b) the potential risk of bleeding (or chyle leak) requiring re-intervention. Surgeons with very low rates of return to theatre for bleeding can afford a higher threshold for placement of a chest drain for this purpose.
Most surgeons place a chest drain routinely after all general thoracic procedures within the hemi-thorax, some surgeons (e.g. Prof Eric Lim) do not place a chest drain routinely for procedures with a) very low risk of bleeding and b) minimal to no air leak after surgery and others (e.g. Prof JianXing He) do not routinely use chest drains and choose to monitor the pleural space using ultrasound. As these practices mature, accompanying data will be available. Whatever your current practice, the drainology board strongly recommend that you undertake continuous audit on safety and outcomes.
Contraindications for Chest Drain Insertion
The decision for the safe removal of a post-operative chest drain is very much part of routine surgical care, and most surgeons would favour the shortest duration possible that is considered to be safe to minimise the length of thoracic drainage. Whilst there are many different protocols with different thresholds, little work has been taken to determine why we place the drains, which influences when we can safely remove them (defined as the limit for which chest drain re-insertion is required).
Work undertaken by Mesa et al, suggests that the principal determinant of duration of chest drainage is the threshold for fluid production (as most thoracic surgical air leaks resolve within 24 hours) and that the higher the threshold the lower the duration of drain. When using 5ml/kg the median drain duration was 3 days compared to 1 day when no upper limit / threshold for fluid was applied. Once fluid criteria was removed, the principal determinant becomes air leak, and when a criteria of <20ml/min for 6 hours, the median duration of a chest drain is 1 day. After drain removal, the average incidence of post-drain removal pneumothorax was 12-13% in the last three years of the study (this is associated with drawing in of air on drain removal which is different from missing ongoing air leak). The post-drain effusion rate when measured by any evidence of costophrenic blunting ranged from 13% to 22%. More pertinent is the rate of drain re-insertion (a reflection of post-drain removal ongoing air leak) with this final criteria was 5%.
In general, the different threshold criteria for air and fluid (from different) protocols will fall somewhere in between the spectrum and will dictate the duration of drain with respect to acceptable outcome (i.e. percentage of drain re-insertions).
Please see the above section for a range of criteria used around the world by our board members.
Mesa-Guzman M, Periklis P, Niwaz Z, Socci L, Raubenheimer H, Adams B, Gurung L, Uzzaman M, Lim E. Determining optimal fluid and air leak cut off values for chest drain management in general thoracic surgery. J Thorac Dis 2015;7(11):2053-2057. doi: 10.3978/j.issn.2072-1439.2015.11.42
Goal is complete evacuation of blood and fluids from around heart and lungs. Existing technology does not work properly in every case: early occlusion rate of chest tubes is high, resulting in „retained blood syndrom“, retrosternal and pericardial blood clots can induce inflammation maintaining fluid accumulation in the chest. Even postoperative atrial fibrillation can be induced by retained clot formations. This leads to increased morbidity and even mortality. In addition, this complications induce a prolonged hospital stay, which can be cost intensive. In the long term this retained fluids can induce pericardial or pleural fibrosis with the consequences of reduced organ function. Most tubes are clotted within 48 hours. Therefore, the drainage is not working adequate. The occlusion is caused by clot formations not only intralumenary but also around the tube. Maintaining a continuous drainage in order to evacuate all fluids would be the optimum.
To manage complications the study of Drainology aims to enable clinicians to:
- Identify if a clinical event is due to chest drainage or not
- Correct any element of chest drainage that is causing a complication
- Manage any consequence of a complication due to chest drainage
- Prevent or reduce the risk of complications due to chest drainage
- Educate patients and their caregivers about avoiding and observing for complications