To this day I still smugly remember the time when as an intern on my respiratory medicine rotation (or house officer as we still often to call it in the UK) I tried to teach the respiratory med resident how to put in a ‘proper’ chest drain in a patient with a large pneumothorax. I meant ‘proper’ as opposed to what I deemed at the time to be the silly little pigtail catheters he was more accustomed to. At this stage in my fledgling career I was already a fully paid up trauma junkie having attended numerous student trauma conferences and having spent a month at Bellevue/NYU Langone as a sub-intern on trauma surgery during my final year at med school. With the misguided confidence (arrogance) of youthful inexperience I went on to subject my unfortunate geriatric patient (victim) to a bloody 20-minute ordeal that left the patient, the resident and other patients in the bay who heard the screams all traumatized in equal measure. Unfortunately for the patient it turned out to be an entirely futile procedure with his pneumothorax not resolving and subsequent CT imaging showing that I had managed to put the tube perfectly into the oblique fissure of the left lung, abutting the mediastinum.
Looking back I think my enthusiasm for finally getting to put in a large bore chest drain (let’s say size 28 Fr upwards) stemmed from my instinctive distrust of the smaller pigtail catheters (9-14 Fr) which I’d seen used to treat chronic effusions secondary to medical conditions, but which I didn’t fancy as being effective for treating traumatic pneumo/haemothoraces. The whole Seldinger thing looked too fiddly and time consuming compared to the scalpel and stiff finger needed to rapidly put in a trauma chest drain. And intuitively I just didn’t see how such a small caliber tube could handle clotting blood. Like needle pericardiocentesis for cardiac tamponade, it just seemed woefully inadequate for the task at hand. And it would seem that my misgivings were backed up by a large number of people in the trauma field with far more knowledge and experience than I had.
Over the years a number of observational studies have attempted to show that small pigtail catheters and large-bore chest drains are equals in terms of effectiveness and complication rates, and if anything the pigtails cause less pain and are therefore arguably superior. Unfortunately these studies were usually underpowered to detect significant differences between the groups, suffered from poor design and were susceptible to selection bias in terms of the patients allocated to pigtail or chest tube insertion.
A 2018 systematic review and meta-analysis from a Taiwanese group looked at 11 studies comprising almost 900 patients comparing pigtail catheters with chest tubes for treatment of pneumothorax. Only 2 of the papers analyzed dealt specifically with the case of traumatic pneumothorax (one an RCT of only 40 patients and the other a retrospective study- both from the same Arizona group). Overall they showed no significant differences in success rates, complication rates, or drainage duration between the two types of chest drains although they conceded that a proper RCT would be needed to add weight to the conclusions.
A single-center and multi-center RCT published last year (again from the Tuscon group) showed similar findings of no significant differences in failure rates, daily drainage output, tube days, intensive care unit and hospital length of stay. And both reported a more favourable patient experience with the use of the smaller pigtail catheters. Again, the patient numbers bring into doubt the validity of the findings with only 43 patients randomized in the single-center study and 119 in the multi-center study, in both cases falling short of the authors’ own targets based on their power calculations. Having said that, these RCTs are baby steps towards building a more solid evidence base in favour of a procedure that may be more tolerable for patients whilst not being inferior to the traditional methods.
The big unanswered question is whether insertion of a pigtail catheter is practical and effective in the trauma patient presenting to ED in extremis. EAST practical management guidelines were updated last year to recommend pigtail catheters in favour of large bore drains for treating traumatic haemothorax in stable patients, however the guidelines still acknowledge the fact that that chest tube thoracostomy remains the preferred choice in emergent situations where the patient is unstable. On that matter, aren’t most people who need an ED chest drain for a haemothorax in some degree of haemodynamic instability? In which case how large is this target population of stable haemothorax patients whose bleeds have not consolidated into a clot too thick to drain easily out of a pigtail catheter?
Ultimately it still comes down to what feels like the right decision to make for the patient in front of you. An isolated haemo or pneumothorax in a clinically stable alert patient may well warrant a pigtail catheter if the person inserting it is familiar with the technique, however this may not be the sensible option in a crashing polytrauma patient with a liter of blood in their chest. From our very first day as interns we all started to subconsciously accumulate knowledge and experience that would shape our attitudes and decision-making going forward. One can only hope that years of first-hand experience and evidence trump the excesses of youthful exuberance.
Obi Nnajiuba is a British surgical resident with a specialist interest in trauma, acute care, prehospital care, triage, mass casualty events and trauma systems. His postgraduate qualifications include an MSc in Trauma Sciences and membership of the Royal College of Surgeons of England. He is also a registered Motorsport UK physician, providing trackside advanced trauma care to competitors at world famous motor-racing circuits such as Brands Hatch, Goodwood and Silverstone.
@drnnajiuba