Pneumothorax/Hemothorax
I. What every physician needs to know.
Pneumothorax can occur spontaneously or be due to trauma or iatrogenic injury. Spontaneous pneumothorax can be primary or secondary in nature; either occurring spontaneously in healthy subjects with no apparent lung disease or occurring secondary to obvious underlying parenchymal lung disease. This chapter will focus on spontaneous primary and secondary pneumothorax and also briefly discuss hemothorax which is usually due to trauma.
Primary spontaneous pneumothorax usually occurs in younger patients, often aged 15-30 years, and is the result of spontaneous disruption of the pleural lining with resultant release of air into the pleural cavity. Secondary pneumothorax develops in persons with underlying lung disease of a variety of types that usually involves and disrupts the visceral pleural surface leading to spontaneous air leak.
II. Diagnostic Confirmation: Are you sure your patient has Pneumothorax/Hemothorax?
Pneumothorax is easily evident on an upright chest radiograph when large, but can be challenging to confirm when small. The characteristic radiographic findings include an obvious pleural edge or line (approximately 1mm) and the absence of lung markings peripheral to this line. Occasionally a "skin fold" may be confused with a pneumothorax. To make this distinction, look for whether the "line" in question extends beyond the chest wall - this is suggestive of a skin fold. Generally, there are no lung markings peripheral to the pleural line. This can be challenging to establish at the upper lung zone where the overlying ribs and clavicle make distinct determinations difficult.
A. History Part I: Pattern Recognition:
In teens or young adults, the onset of a pneumothorax is typically heralded by pain and varying degrees of dyspnea that leads the affected individual to seek emergency care. This pain may be accompanied by severe shortness of breath or, in cases of tension pneumothorax, substantial distress. The onset is usually entirely spontaneous, but can occur with lifting, sneezing, valsalva, or athletic activities such as weight training or wrestling.
B. History Part 2: Prevalence:
Males are affected more then females; affected individuals are often of tall, slender body-habitus, though not necessarily Marfanoid in appearance.
C. History Part 3: Competing diagnoses that can mimic Pneumothorax/Hemothorax.
It is important to carefully examine the lung parenchyma radiographically for suggestion of obvious lung disease. While this is not apparent in spontaneous pneumothorax, such cases are ultimately noted to be attributable to subpleural blebs or bullae in the majority of individuals at surgery (if surgery is necessary).
D. Physical Examination Findings.
When the pneumothorax is small (< 10-20%), physical exam may be unrevealing. More substantial pneumothoraces are usually accompanied by diminished breath sounds on lung auscultation. If tension occurs, tachycardia, tachypnea, and deviation of the trachea may be evident with absent breath sounds or truncal crepitus to suggest subcutaneous emphysema.
E. What diagnostic tests should be performed?
An upright chest X-ray is often sufficent, but repeat studies, if a skin fold is suspected, or expiratroy films can be obtained. A computed tomography (CT) of the thorax can be obtained if there is a question of underlying parenchymal lung disease. This can be ordered with high resolution for greater detail to appreciate any interstitial lung disease. Contrast infusion is not required for examination of parenchymal lesions.
1. What laboratory studies (if any) should be ordered to help establish the diagnosis? How should the results be interpreted?
While plain chest X-ray is the diagnostic study of choice, ultrasound is emerging as an important bedside diagnostic test. The sliding lung sign or "gliding lung" sign indicates two layers of opposing pleura and has a high negative predictive value. The absence of this sign is not definitive for a pneumothorax as other explanations are possible.
2. What imaging studies (if any) should be ordered to help establish the diagnosis? How should the results be interpreted?
Upright chest X-ray.
Consider ultrasound to detect iatrogenic causes of pneumothorax. For example, this can be done at the bedside directly after central line placement.
CT scanning will be diagnostic, but is often too time consuming and risks the development of tension while the patient is in the scanner. It is best used as a secondary tool to detect parenchymal lung disease once the pneumothorax has been documented and treated.
F. Over-utilized or “wasted” diagnostic tests associated with this diagnosis.
N/A
III. Default Management.
Patients with small primary pneumothoracies (<15%) can be observed either in the ER setting or in the hospital for at least 6 hours. Oxygen administration accelerates the reabsorption rate by creating a gradient for nitrogen from the pneumothorax where [N2] is typically 79% to the parenchyma and lung capillaries where the [N2] is reduced due to the supplemental oxygen. Larger pneumothoracies often require chest tubes (7-14 guage), but aspiration to remove air can be a successful management strategy.
A. Immediate management.
Oxygen
Monitoring of vital signs
B. Physical Examination Tips to Guide Management.
The presence of hypotension with obvious signs of pneumothorax and or mediastinal shift (such as shift of the trachea away from the side of the pneumothorax) may prompt more urgent decompression with an angiocatheter (16 gauge is recommended) placed just above the second anterior rib. An obvious "rush" or release of air will confirm suspected tension. This will then be followed by an improvement in the blood pressure.
C. Laboratory Tests to Monitor Response To, and Adjustments in, Management.
Repeat X-rays will confirm the resolution of the pneumothorax and should be repeated with the chest tube off of wall suction, but on water seal. Stability of the lung on water seal with re-expansion of the lung will confirm that the chest tube is ready for removal. A persistent air leak through the tube or recurrence of the pneumothorax will indicate continued leak of air. In such cases the tube should be continued for an additional 12-24 hours, repeating the above tests.
D. Long-term management.
A first event may be treated with observation or chest tube alone. Recurrent episodes or persistent air leaks should prompt thoracic surgical consultation and consideration for VATS (video-assisted thoracoscopic surgery) which is highly effective in preventing recurrence. VATS has a better than 95% success rate in treating the current episode and preventing recurrence.
E. Common Pitfalls and Side-Effects of Management.
An air leak which persists despite clamping the chest tube suggests a break or defect in the tubing system and should be corrected.
IV. Management with Co-Morbidities.
Spontaneous pneumothorax in the setting of overt parenchymal lung disease (secondary spontaneous pneumothorax) is more concerning because patients do not tolerate pneumotharax as well. This is due to the baseline abnormalities in gas exchange due to the underlying disease. As such, tube thoracostomy is the preferred management strategy and a larger bore tube should be placed by a competent surgeon. Underlying lung disease associated with pneumothorax include COPD, pulmonary langerhans cell histiocytosis, lymphangioleiomyomatosis, tuberous sclerosis complex, pulmonary endometriosis, sarcoidosis, lung cancer, and pulmonary interstitial diseases.
Treatment of the underlying disease may be required and VATS should be considered even with a first event.
Treatment of the underlying lung disease is also warranted.
A. Renal Insufficiency.
No change in standard management.
B. Liver Insufficiency.
No change in standard management.
C. Systolic and Diastolic Heart Failure.
No change in standard management.
D. Coronary Artery Disease or Peripheral Vascular Disease.
No change in standard management.
E. Diabetes or other Endocrine issues.
No change in standard management.
F. Malignancy.
A chest tube is often required at presentation.
G. Immunosuppression (HIV, chronic steroids, etc).
Caution is advised when patients are taking steroids as this can affect healing and lead to air leaks if VATS is required.
H. Primary Lung Disease (COPD, Asthma, ILD).
A chest tube is often required at presentation.
I. Gastrointestinal or Nutrition Issues.
No change in standard management.
J. Hematologic or Coagulation Issues.
No change in standard management.
K. Dementia or Psychiatric Illness/Treatment.
No change in standard management.
V. Transitions of Care.
A. Sign-out considerations While Hospitalized.
When hospitalized patients have progressive symptoms, check a chest X-ray and consider placing the chest tube (if present) back to wall suction.
B. Anticipated Length of Stay.
Length of stay should be brief (1-3 days). For small pneumothoracies, patients can be observed for 6 hours. When a chest tube is required, a hospital stay is generally necessary.
C. When is the Patient Ready for Discharge.
When the chest tube can be successfully discontinued and a confirmatory chest X-ray 4 hours later is free of any recurrence, then the patient is ready to go home. Patients with persistent leaks can be managed with a Heimlich valve if surgery cannot be scheduled rapidly.
D. Arranging for Clinic Follow-up.
While follow-up with an X-ray is generally recommended, it is most important to educate the patient about when to return and to be alert to the possibility of ipsilateral or contralateral symptoms.
1. When should clinic follow up be arranged and with whom.
Follow-up in pulmonary or thoracic surgical clinic is advisable.
2. What tests should be conducted prior to discharge to enable best clinic first visit.
A chest radiograph before the first visit will confirm resolution. Further testing is only required if underlying parenchymal disease is suspected.
3. What tests should be ordered as an outpatient prior to, or on the day of, the clinic visit.
If parenchymal lung disease is suspected pulmonary function tests (PFTs) and a non-contrast CT scan of the thorax with high resolution is advised.
E. Placement Considerations.
None
F. Prognosis and Patient Counseling.
Patients with first events need to be counseled about the risk of recurrence. In patients who are treated with observation, aspiration, or chest tube, the recurrence rate may be as high as 30-50%.
VI. Patient Safety and Quality Measures.
A. Core Indicator Standards and Documentation.
Chest tube, if required should be placed intrathoracically and on the correct side 100% of the time.
B. Appropriate Prophylaxis and Other Measures to Prevent Readmission.
Smoking cessation is advised in all affected individuals.
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