Continuing Education Activity

Pneumothorax is gas in the pleural space. This condition can present in one of three ways: spontaneous (primary), secondary, and traumatic. This activity focuses on a subset of traumatic pneumothoraces known as iatrogenic pneumothorax This refers to a pneumothorax that has developed secondary to an invasive procedure such as pulmonary needle biopsy (transthoracic and transbronchial), placement of a central venous line or positive pressure ventilation. This activity reviews the pathophysiology of pneumothorax and highlights the role of the interprofessional team in its management.

Objectives:

• Describe the pathophysiology of pneumothorax.
• Review the presentation of a patient with a pneumothorax.
• Summarize the treatment options for pneumothorax.
• Explain modalities to improve care coordination among interprofessional team members in order to improve outcomes for patients affected by pneumothorax.

Introduction

Pneumothorax is gas in the pleural space. This condition can present in one of three ways: spontaneous (primary), secondary, and traumatic. This activity focuses on a subset of traumatic pneumothoraces known as iatrogenic pneumothorax  This refers to a pneumothorax that has developed secondary to an invasive procedure such as pulmonary needle biopsy (transthoracic and transbronchial), placement of a central venous line or positive pressure ventilation.[1]  As a complication of one of these, a tension pneumothorax can develop when the pressure in the pleural space is positive throughout the respiratory cycle. This leads to decreased venous return, hypotension, and hypoxia. A pneumothorax can range from asymptomatic to potentially life-threatening. Iatrogenic pneumothorax is a patient safety indicator (PSI) of the above procedures.

Etiology

An iatrogenic pneumothorax is a known complication of invasive procedures such as pulmonary needle biopsy (transthoracic and transbronchial), placement of a central venous line, or positive pressure ventilation.[1] However, this condition can arise from many other procedures involving the thorax and abdomen. Case reports include bilateral pneumothoraces after incorrect placement of a nebulization kit in a spontaneously breathing intubated patient,[2] after insertion of a hypoglossal nerve stimulator,[3] or even after acupuncture.[4] Subclavian insertion of a central venous line (CVL), however, is the most common procedure associated with an iatrogenic pneumothorax.[5]

Epidemiology

The incidence of an iatrogenic pneumothorax is directly proportional to the number of invasive procedures performed.[6] Patients in unstable trauma or code situations are more likely to undergo an invasive intervention. This along with limited access to internal jugular sites when a non-femoral vein site is desired results in an elevated risk for iatrogenic pneumothorax.[5]

Pathophysiology

Any intervention in proximity to the abdomen, especially the thorax, can cause an iatrogenic pneumothorax. This is especially true when placing a subclavian central venous catheter without the use of ultrasound (i.e., "blindly") using landmarks.   In landmark-based subclavian central venous catheter placement, per Kilbourne et al.,[7] six common technical errors include inadequate landmark identification, improper insertion position, insertion of the needle through periosteum, taking too shallow a trajectory with the needle, aiming the needle too cephalad, and failure to keep the needle in place for wire passage. Landmark technique also depends on the ability and experience of the medical professional performing the procedure, making iatrogenic pneumothorax more likely in a tertiary teaching hospital.[8]

History and Physical

The presentation in a patient with a pneumothorax can range from asymptomatic to life-threatening based on the size, rate of development, and the health of the underlying lung. An iatrogenic pneumothorax is part of a differential diagnosis in a patient with pleuritic pain and dyspnea, tachypnea, and tachycardia. Decreased or absent breath sounds on the affected side is highly suspicious. Any pneumothorax can become a tension pneumothorax. Findings could include hypoxia, hypotension, distended neck veins, a displaced trachea, and unilaterally decreased breath sounds.[9] 

Evaluation

Iatrogenic pneumothorax can be diagnosed clinically. Point-of-care ultrasound has the advantage of being rapid, highly sensitive and specific, and easily repeatable. Suggestive findings include the lack of pleural sliding. A "point sign" (sliding pleural next to non-sliding pleura) is diagnostic. An upright posteroanterior chest radiography has 83% sensitivity.[9] Chest CT is more sensitive than chest radiography but inherently results in a delay in treatment.

Treatment / Management

First, determine if the patient is stable or unstable. Next, provide supplemental oxygen at a rate to maintain adequate oxygenation.[10] Some patients with small pneumothoraces may resolve with observation.[11] Definitive treatment options of a pneumothorax include needle aspiration, chest tube drainage, video-assisted thoracic surgery (VATS), and open surgical intervention.[12] Treatment takes precedence over imaging. If felt to be clinically unstable, the traditional first step is to perform a needle aspiration or decompression to reduce the excess air in the pleural space. Place a large-bore needle in the second intercostal space in the midclavicular line as a temporary measure.[13][14] Finger thoracostomy is the most recently used technique. One makes an incision over the lateral chest wall in the "safe triangle" formed by the lateral border of the pectoralis major, the lateral border of the latismus dorsi, the fifth intercostal space, and the base of the axilla. Next, one inserts a finger over the fifth intercostal space and bluntly dissects into the pleural space. It is fast and safe as it does not cause a pneumothorax and addresses the increasing girth of today's patients. Thoracostomy is the definitive therapy and uses the negative pressure generated by a water seal or suction to reduce air in the pleural space.[15] Chest tubes are inserted in either the second or third intercostal space of the midclavicular line (Monaldi position). They can also be inserted anterior to the mid-axillary line of the fourth or fifth intercostal space (Bulau position).[16] The other two treatment choices are purely surgical and reserved for severe cases.[17]

Differential Diagnosis

Although the diagnosis of pneumothorax should be definite and precise, a patient presenting with pleuritic pain without further management should elicit a robust differential diagnosis [10] such as:

• Myocardial infarct
• Myocardial ischemia
• Pulmonary embolus
• Pericarditis
• Pleurisy
• Pneumonia

Pertinent Studies and Ongoing Trials

Given that iatrogenic pneumothorax is a patient safety indicator (PSI) that is directly related to invasive procedures, most of the pertinent studies and ongoing trials focus on quality improvement and incidence reduction. Central venous catheter insertion is the main cause of iatrogenic pneumothoraces; so, patient factors (underlying condition, anatomy, restlessness, previous procedures), procedure decision-making (site, catheter type), and clinical factors are given particular consideration for improvement of outcomes.[18] Another quality improvement observational study in a tertiary care hospital demonstrated improvement and a sustained reduction of iatrogenic cases through a multifaceted intervention. This consisted of clinical and documentation standardization, the addition of cognitive aids, simulator training, use of ultrasound equipment, and feedback to clinical services.[5] Other studies have linked physicians-in-training to worse outcomes due to lack of experience[8]; however, simulation-based mastery has shown to improve patient outcomes.[19]

Prognosis

The estimated risk of pneumothorax recurrence is 23% to 50% over a 1- to 5-year follow-up period, with the highest risk during the first month.[20] However, there is no data for recurrence or incidence changes specific to iatrogenic pneumothoraces. In patients who underwent tube thoracostomy, it is safe for them to fly as early as 72 hours after tube removal without increased risk of recurrence.[21]

Complications

Tension pneumothorax is the most notable complication of any pneumothorax previously described. This disorder is life-threatening and requires immediate intervention.[22] Another well-described complication of pneumothorax is having a persistent air leak and/or failure of lung re-expansion, which usually require further surgical intervention.[23]

Deterrence and Patient Education

A pneumothorax, also known as a collapsed lung, occurs when air (either from the lung or outside) collects in the space between the lung and the chest wall. The focus of this article is the specific cause of a collapsed lung, called iatrogenic or caused accidentally during surgery or a procedure. Symptoms of a collapsed are a sharp or stabbing chest pain and/or trouble breathing. People with small amounts of air may not have any symptoms at all. This condition can be an emergency and require immediate treatment. Treatment involves extracting the air trapped between the lung and the chest wall by either a needle, scalpel and finger, or chest tube. Regardless, a chest tube is inserted and stays in place until the lung expands to its normal size. Some individuals with severe cases may require surgery. After being treated for a collapsed lung with a tube, chances of having a recurrence is low but possible. Patients should avoid scuba diving and flying in a plane for at least 72 hours.[24]

Pearls and Other Issues

• Iatrogenic pneumothorax is a patient safety indicator (PSI) condition.  It is a traumatic pneumothorax secondary to an invasive procedure or surgery.
• The most common cause is the placement of a subclavian central venous line (CVL).
• Other causes include pulmonary needle biopsy (transthoracic and transbronchial), nasogastric tube placement, or positive pressure ventilation. There are case reports after placing nebulizer kits and acupuncture to the chest wall.
• The presentation is mainly pleuritic chest pain and dyspnea with decreased to absent breath sounds on the affected side during or after a procedure.
• Treatment should not be delayed for imaging.
• The diagnosis is ideally made clinically. Ultrasound evaluation to check for pneumothorax is emerging as a very accurate and rapid tool.
• Treatment is needle decompression followed by tube thoracostomy. VATS and open thoracotomy are reserved for recurrent or severe cases.

Enhancing Healthcare Team Outcomes

Iatrogenic pneumothorax is an important PSI condition associated with morbidity and mortality. Iatrogenic pneumothoraces are attributed to procedure techniques/decision-making pitfalls, medical provider experience, and not using ultrasound during CVC placement.[25] (Level V) Recent systematic reviews have focused on the role of simulation-based education addressing all the common causes. This training results in the improvement of CVC techniques and reduction of iatrogenic pneumothorax cases.[26][27][28] (Level I) In an academic tertiary care hospital, an interprofessional team including physicians, nurses, and administrative leaders improved and sustained a reduction in iatrogenic pneumothoraces. This was done by implementing clinical documentation standards, cognitive aids, simulation training, purchase/employment of ultrasound equipment, and feedback to clinical services.[5] (Level I) The role of interprofessional communication and care coordination between health professionals cannot be understated when considering patient outcomes.