Senior Report 8.19

 Case Presentation by Laura Smylie, MD

A 14 year old girl who presents with nausea and vomiting for one day and an abrupt onset of chest pain.
Vitals: BP 100/67, HR 121, RR 25, Temp 36.7, 100% on room air.

 

Questions:
1. What is the diagnosis based upon the above x-rays?
a) Foreign body
b) Pneumothorax
c)Pneumomediastinum
d)Apical pneumonia

2. What is the likely etiology of the radiographic finding?
a) alveolar rupture secondary to forceful retching
b) esophageal rupture secondary to forceful retching
c) acute PE
d) no abnormality on chest x ray.

3. What is the most appropriate initial management of this patient?
a) place on continuous pulse oximetry, place a left sided chest tube
b) place on continuous pulse oximetry, 4mg ondansetron, NPO.
c) place on a continuous cardiac monitor, start heparin drip, consult cardiology.
d) send blood cultures, start antibiotics, encourage PO intake.

 

Answers and discussion:

1) C
2) A
3) B

1) C – Pneumomediastinum. You can see air tracking in the soft tissues of the neck and the upper aspects of the mediastinum. Although there could potentially be a pneumothorax (B) associated with this this, no pneumothorax can be seen in this study. No foreign body (A) is present and there is no infiltrate to suggest pneumonia (D).

 

2) A – Alveolar rupture secondary to forceful retching is the most likely etiology of the pneumomediastinum, although you should also be concerned for possible esophageal rupture secondary to forceful wretching (B) also known as Boerhaave’s esophagus. Review of the literature shows that in similar presentations, esophograms are typically negative for tears in the esophagus. Acute PE (C) has not been shown to present with free air. On a chest xray, the most concerning (and classically pimped) findings for acute PE are Hampton’s Hump and Westermark’s sign. Hampton’s Hump, represented in the first image below, shows a wedge shaped area of hyperdensity along the lung parenchyma periphery, indicative of an infact/PE. Westermark’s sign, as shown in the second image below, shows a focal peripheral hyperlucency secondary to oligemia, with or without dilation of the central pulmonary vessels.

 

3) B – Although there is no obvious pneumothorax on the initial chest x ray, you must keep a high level of suspicion for a small pneumothorax. This would not necessitate chest tube placement (A), but a nonrebreather and continuous pulse oximetry are appropriate if a small pneumothorax is present. Given that the retching led to the pneumomediastinum, treat her nausea with ondansetron. She should be kept NPO until an esophagram can be obtained (as an inpatient or in the observation unit) to definitively rule out Boerhaave’s esophagus. As an inpatient, the chest x ray should repeated in 6-8 hours. C is the treatment for a non-massive PE or NSTEMI; D is the treatment for pneumonia, neither of which applies in this case.

The percentage of pneumothorax will guide therapy. This picture illustrates that 2 cm pneumo is typically the cut off point for inserting a chest tube with a spontaneous pneumo but not necessarily with a traumatic pneumo.

 

References:

Spontaneous pneumomediastinum: diagnostic and therapeutic interventions. Al-Mufarrej F, Badar J, Gharagozloo F, Tempesta B, Strother E and Margolis M. Journal of Cardiothoracic Surgery 2008, 3:59 doi:10.1186/1749-8090-3-59

BMJ Case Rep. 2012 Oct 10;2012. pii: bcr0320091647. doi: 10.1136/bcr.03.2009.1647.

http://radiopaedia.org/articles/westermark-sign

https://www.tumblr.com/usmlepathslides/53392063709/westermarks-sign-cxr-note-the-area-of

Gantner J, Keffeler JE, Derr C. Pulmonary embolism: An abdominal pain masquerader. J Emerg Trauma Shock [serial online] 2013 [cited 2015 Mar 26];6:280-2. Available from: http://www.onlinejets.org/text.asp?2013/6/4/280/120376