Discharge that pneumothorax!

The first, rather eccentric, paper that addressed the discharge of pneumothorax patients in lieu of hospital admission was published in 1997 by a community hospital surgeon. He treated 14 consecutive patients with pneumothorax by placing pediatric chest tubes that were attached to one-way Heimlich valves. Fifteen to 30 minutes after placement, these patients had a chest X-ray confirming lung re-expansion. If the pneumothorax had resolved and “thoracostomy relieved respiratory embarrassment,” patients were then discharged with return precautions and follow-up in 5-7 days for tube removal. Of the 14 patients treated, 3 returned and were admitted for pain, anxiety, or a vasovagal reaction. Importantly, there were no fatalities or bad outcomes as a result of discharging these patients (aside from a return trip to the hospital).^[1]

A Heimlich valve. Used in extreme cases of respiratory embarassment.

As a result of this study, this surgeon demonstrated to the medical community that he either works in a community with little malpractice litigation, he had cajones the size of watermelons, or possibly both. Additionally, it opened the door to more thorough studies examining the possibility of discharging patients with pneumothoraces from the ED.

More than a few studies since then have taken a more comprehensive look at discharging patients with a pneumothorax from the ED. A prospective, observational study of 60 patients examined the treatment of small pneumothoraces with brief observation and possible pigtail placement only if they had radiolographic or symptomatic worsening. These patients, if deemed stable, were then discharged with or without a pigtail catheter/Heimlich valve. Large pneumothoraces were treated with immediate pigtail placement followed by observation and discharge. All patients had follow-up on days 1 and 7. The results were that 50% of individuals eventually needed admission, but there were no major adverse outcomes as a result of initial discharge.^[2]

Another prospective study of 48 patients compared placement of pigtail catheter vs. needle aspiration and measured rates of successful discharge. It concluded that needle aspiration was slightly less effective at stabilizing patients enough for discharge but was also associated with less procedural complications. There were 2 episodes of subcutaneous emphysema seen in the aspiration group and 1 tension pneumothorax in the pigtail catheter group.^[3]

It should be noted that in each of these studies, patients that were sent home were both hemodynamically stable and reliable with good follow-up. One³ went so far as to exclude patients who did not meet the criteria of stability, resided > 1 hour from the hospital or were solitary, unreliable, or would be discharged after 20:00. Both of these studies are small; however, the limited data suggests that it may allow shared decision-making with select patients about possible discharge.

In line with these conclusions, a review by Repanshek et al^[4] recommends simple observation for 3-6 hours for pneumothorax of <20% lung volume and then thoracostomy only if the patient’s pneumothorax progresses symptomatically or radiographically. If the pneumothorax is larger than 20%, the authors recommend a trial of needle aspiration. If there is no radiographic resolution immediately post-procedure or more than 4L of air is removed, authors then recommend placing a small-bore pigtail catheter. All patients with a symptomatically and radiographically stable pneumothorax after observation and possible aspiration or pigtail placement are then candidates for discharge with 24-48 hours follow-up.

The British Thoracic Society is essentially in agreement with these authors (or rather the authors are in agreement with BTS, as the BTS guidelines were published first). According to the 2010 guidelines, “small” (<2cm), asymptomatic, primary pneumothoraces should be observed without intervention. If small and symptomatic, start with aspiration. Both of these cohorts should be considered candidates for discharge if improved. Chest tubes should only be placed in these groups if symptoms worsen; in cases where chest tubes are placed, patients should then be admitted. Secondary pneumothoraces (i.e., patients with underlying lung disease) should be admitted regardless but may be observed without intervention if asymptomatic. If >2cm or symptomatic, tube thoracostomy is recommended.^[5] See flow sheet.

If you are looking for lung sliding and you see this, your probe is in the wrong spot.

The 2010 BTS guidelines encourage radiographic evaluation of patients under observation or after aspiration. However, in an era where bedside ultrasonography is playing an increasing role in emergency care, it’s possible to assess a pneumothorax during the course of treatment without exposing the patient to multiple rounds of radiation. In fact, reviews on the subject suggest that ultrasound is at least as sensitive and specific for detection as a conventional chest X-ray.^{[6], [7]} And although size cannot be determined as part of the BTS guidelines, one may consider using bedside ultrasonography to assess resolution after treatment.

Select, stable, reliable patients with a primary pneumothorax may be considered candidates for discharge from the emergency department after observation, needle aspiration, or pigtail catheter placement in a healthcare system with good follow-up infrastructure in place. There should be a conversation with the patient clarifying that there is a likelihood they will need to return for potential chest tube placement and admission. Initiating this conversation doesn’t seem to decrease negative outcomes, but it may reduce admissions, expenses, and potentially unnecessary procedures.