Normal pleural space = closed sac in which negative pressure is essential for normal lung expansion during breathing (simplified: space b/w lungs and chest wall) *Remember from physics: Areas of high pressure will move into areas of lower pressure (I.e. when we exhale, we force air out of lungs, creating large area of negative pressure in pleural space, which entices air to rush back into lungs when we open mouth; inhalation = opposite, lots of positive pressure introduced into lungs, smaller negative pressure in pleural space around lungs). “OPEN” vs. “CLOSED” chest injuries: open injuries have significant potential to compromise efficacy of pleural space and therefore respiratory function. Also potential for infection of exposed vital organs/systems, plus cavity area can pool blood quickly (internal bleeding).
Primary-smokers suggestive of subclinical disease ---------------------- primary spontaneous (no obvious underlying lung disease), secondary spontaneous (underlying lung disease), and iatrogenic pneumothoraces (which are traumatic but typically are smaller and more easily managed) Primary spontaneous pneumothorax seems to result from rupture of a subpleural bleb, usually in an upper lobe.5 These blebs are usually multiple and have increased wall tension, allowing distention and eventual rupture. The mechanism of bleb formation remains unknown, but higher upper lobe transpulmonary pressure, local ischemia from decreased upper lobe blood flow, and subclinical emphysema-like changes have been postulated ------------------- Primary spontaneous pneumothorax Air in the intrapleural space without preceding trauma and without underlying clinical or radiologic evidence of lung disease Typically in patients who are between 18 and 40 years of age Primary spontaneous pneumothorax occurs in individuals without known lung disease and accounts for two-thirds of spontaneous pneumothoraces Secondary spontaneous pneumothorax Occurs in patients with underlying pulmonary structural pathology Air enters the pleural space via distended, damaged, or compromised alveoli May present with more serious clinical symptoms and sequelae due to comorbidity Iatrogenic pneumothorax Medical procedure resulting in traumatic pneumothorax (usually from a small-bore hollow needle) Iatrogenic pneumothorax occurs secondary to a diagnostic or therapeutic procedure and is really a subset of penetrating traumatic pneumothorax. ------------------------------ Primary spontaneous pneumothorax Spontaneous pneumothorax is heavily associated with smoking, with 80-90% of primary spontaneous pneumothorax cases occurring in smokers. Physical height: It has been noted that typical patients tend to have a tall and thin body habitus. Whether height affects development of subpleural blebs or whether more negative apical pleural pressures cause preexisting blebs to rupture is unclear. Valsalva results in increased intrathoracic pressure. However, contrary to popular belief, most spontaneous pneumothoraces occur while the patient is at rest. Changes in atmospheric pressure, proximity to loud music, and low frequency noises have also been reported to be associated with pneumothorax Familial associations have been noted in more than 10% of patients. Some are due to rare connective tissue diseases, but recently, mutations in the gene encoding folliculin (FLCN) have been described. These patients may represent an incomplete penetrance of a genetic disorder. Birt-Hogg-Dube syndrome is characterized by benign skin growths, pulmonary cysts, and renal cancers and is caused by mutations in the FLCN gene. Secondary spontaneous pneumothorax COPD or emphysema Asthma Cystic fibrosis Interstitial lung disease Tuberculosis Bronchogenic or metastatic carcinoma Pneumonia (fungal, caseating, HIV) Collagen vascular disease including Marfan syndrome Catamenial pneumothorax --------------------------- The most common underlying abnormality in secondary spontaneous pneumothorax is COPD ----------------------------------------- Regardless of the inciting event, once there is a break in the pleura, air travels down a pressure gradient into the intrapleural space until pressure equilibrium occurs with partial or total lung collapse. Altered ventilation perfusion relationships and decreased vital capacity then contribute to dyspnea and hypoxemia
Iatrogenic pneumothorax occurs secondary to a diagnostic or therapeutic procedure and is really a subset of penetrating traumatic pneumothorax.
Spontaneous pneumothoraces in most patients occur from the rupture of blebs and bullae. While primary pneumothorax is defined as a lack of underlying pulmonary disease, these patients have asymptomatic blebs and bullae detected on CT scans or upon thoracotomy. Until a bleb ruptures and causes a pneumothorax, no clinical signs or symptoms are present.The pleural space has a negative pressure, with the chest wall tending to spring outward and the lung&apos;s elastic recoil tending to collapse. If the pleural space is invaded by gas from a ruptured bleb, the lung collapses until equilibrium is achieved or the rupture is sealed. As the pneumothorax enlarges, the lung becomes smaller. The main physiologic consequence of this process is a decrease in vital capacity and partial pressure of oxygen. Young and otherwise healthy patients can tolerate these changes fairly well, with minimal changes in vital signs and symptoms, but those with underlying lung disease may have respiratory distress.
Equilibrium between intrathoracic and atmospheric pressure is immediate..
Spontaneous pneumothorax Tachycardia (most common) Tachypnea Hypoxia ----------------------- Symptoms are related to the size of the pneumothorax, rate of development, and underlying clinical status of the patient. ---------------------------------------------- Acute pleuritic chest pain occurs in 95 percent of patients and localizes to the side of the pneumothorax in &gt;90 percent of cases. Dyspnea occurs in 80 percent of patients, and predicts a larger pneumothorax. Patients with COPD who develop a spontaneous pneumothorax may acutely decompensate, with 1 to 17 percent mortality.
Decreased breath sounds occur over the affected lung 85 percent of the time, but only 5 percent have tachypnea of more than 24 breaths/min or tachycardia of more than 120 beats/min. Hyperresonance occurs in fewer than one-third. Tracheal deviation and hemodynamic compromise are the hallmarks of tension pneumothorax that demand immediate treatment
Short-term complications of spontaneous pneumothorax include tension pneumothorax, failure to reexpand, persistent air leak, and complications related to the removal of intrapleural air, such as infection, technical errors, and reexpansion pulmonary edema --------------------- Recurrence of pneumothorax is the major long-term complication and the reason that all patients with spontaneous pneumothorax require referral for potential definitive therapy. Primary spontaneous pneumothorax recurs in approximately 20 to 30 percent of patients and is independent of the method chosen to remove the intrapleural air ---------------- Secondary spontaneous pneumothorax recurs in 40 to 50 percent of patients
Chest radiography for evaluation of pneumothorax Although expiratory images are thought to better depict subtle pneumothoraces (the volume of the pneumothorax is constant and hence proportionally higher on expiratory images), a randomized controlled trial revealed no difference in the ability of radiologists to detect pneumothoraces on inspiratory and expiratory images. In patients with underlying pulmonary disease, the classic visceral pleural line may be harder to detect because the lung is hyperlucent, and little difference exists in the radiographic density between the pneumothorax and the emphysematous lung. Ratio of lung size to hemithorax size to estimate pneumothorax size avoids the subjective underestimation of pneumothorax expressed as a percentage of previous lung volume The size of a pneumothorax may be estimated by using the ratio of the lung diameter cubed to the hemithorax diameter cubed. This formula assumes a constant shape of the lung when it collapses and is invalid if pleural adhesions are present. A simple approach to classification of the pneumothorax as small or large involves measuring the distance from the apex of the lung to the top margin of the visceral pleura (thoracic cupola) on the upright chest radiograph. Small pneumothorax: &lt;3 cm distance to the apex Large pneumothorax: &gt;3 cm distance to the apex A supine chest radiograph may depict the deep sulcus sign (very dark and deep costophrenic angle). The anterior costophrenic recess becomes the highest point in the hemithorax, resulting in an unusually sharp definition of the anterior diaphragmatic surface due to gas collection and a depressed costophrenic angle. -------------------------------------------- CT of the thorax When performed on primary spontaneous pneumothorax patients, CT detects multiple blebs and bullae in the setting of negative chest radiographic findings. This may not impact management, as there has been no correlation between number of blebs and recurrence. CT can detect occult pneumothorax in patients who will require mechanical ventilation in trauma and emergency surgery settings. CT has also been shown to be more sensitive than radiography for hemothorax and pulmonary contusion. While the role of CT in trauma patients is evolving, it is controversial whether it significantly alters management and is not indicated in primary spontaneous pneumothorax. CT may have a role in secondary spontaneous pneumothorax, especially to differentiate from giant bullous emphysema. ------------------------------------------------------------------------------------- Ultrasonography Ultrasonography can be used as a possible bedside technique to detect pneumothorax. It may be useful in unstable patients who cannot undergo radiologic studies outside of the emergency department. Many trauma centers are incorporating chest ultrasonography as an adjunct to the Focused Assessment with Sonography in Trauma (FAST) examination used for trauma patient screening. Ultrasonography is operator dependent. -------------------------------
Skin fold mimicking pneumothorax. A: AP supine chest radiograph shows opacification of the right medial lung outlined by a sharp edge (skin fold; arrows). Note that the lung peripheral to this edge is not hyperlucent, a clue that there is no pneumothorax. B: AP upright chest radiograph obtained 1 hour later no longer shows the skin fold. Redundant skin can result in skin folds on the chest radiograph, especially when the patient is supine. Changing patient positioning is often useful in differentiating a skin fold from a pneumothorax.
Pseudo-pneumothorax caused by a skin fold, scapular border, or tubing, is differentiated from true pneumothorax by looking for vascular markings inside the confines of the radiolucent area and the blending of these lines into the chest wall, rather than following the borders of a collapsed lung. Large bullae have been mistaken for pneumothoraces, but bullae and cysts have concave inner margins and rounded edges. severe bullous COPD may mimic pneumothorax, and careful review of the CXR is needed with confirmatory CT, if the patient is stable. A thoracostomy with the chest tube inserted into a bulla mistaken for a pneumothorax results in a large pneumothorax, associated bronchopulmonary fistula, and its complications --------------------------------------- Chest tube track mimicking pneumothorax. A: PA chest radiograph, coned to the left upper hemithorax, shows a thin curvilinear opacity paralleling the chest wall (arrows). B: AP chest radiograph obtained 1 day earlier shows a chest tube following the course of the opacity seen in (A).
Pneumothorax in a supine patient. AP supine chest radiograph shows the â€œdeep sulcusâ€ sign of pneumothorax on the right (curved arrow) and a basilar pneumothorax on the left (straight arrows) --------------------------------- Pneumothorax is much more difficult to detect on a supine anteroposterior radiograph. On the anteroposterior view, a deep sulcus sign, representing a deep lateral costophrenic angle, sometimes is a clue to a pneumothorax.
The Lung Point, a Sign Specific to Pneumothorax A patient with hard-to-detect or absent lung sliding and absence of interstitial syndrome will have an ultrasound profile of pneumothorax, i.e., a false-positive image. we can build a specific sign: with immediate and fleeting visualization at a precise location of the chest wall and along a definite line, at a precise moment of the respiratory cycle, usually inspiration, with the probe strictly motionless, the operator finds either lung sliding, lung rockets, or alteration of A lines, in an area previously observed with no lung sliding and the A-line sign, i.e., patterns that were barely suggestive of pneumothorax This sign has been called the lung point sensitivity of 66% and a specificity of 100% This sign can be explained if one considers that any lung, at the wall or not, in spontaneous or mechanical ventilation, will slightly increase its volume on inspiration. Therefore, a lung sign will appear at the boundary area, at the precise line where the lung reaches the wall, since the lung surface in contact with the wall will increase .The poor sensitivity of ultrasound is easily explained: major, completely retracted pneumothorax will never touch the wall.
Emergency department evaluation and management of pneumothorax centers on immediate management of complications such as tension pneumothorax or ventilatory failure, and then on eliminating the intrapleural air and optimizing pleural healing.
Clinical diagnosis Don’t wait for radiological diagnosis Needle coverts it into simple pneumo…
All sides-tension pneumothorax
There is general agreement that a tension pneumothorax must be treated as an emergency by inserting a wide-bore needle or intercostal catheter (Davies, 1969), which can be connected subsequently to an underwater seal or to a valve (Knight, 1967). There is, however, considerable controversy about the treatment of cases not under tension. -------------------------- Primary - rupture of apical pleural blebs, small cystic spaces that lie within or immediately under the visceral pleura Nearly all patients with secondary pneumothorax should be treated with tube thoracostomy because of the lack of pulmonary reserve in these patients ---------------------------- Primary spontaneous pneumothorax If the pneumothorax is smaller than 15% (or estimated as small, see Imaging Studies) and the patient is symptomatic but hemodynamically stable, needle aspiration is the treatment of choice. If the pneumothorax is smaller than 15% and if the patient is asymptomatic, many consider observation to be the treatment of choice. (If the patient is admitted, administer oxygen, since this has been shown to speed resolution of the pneumothorax.) If the pneumothorax is greater than 15% (or estimated as large, see Imaging Studies), aspiration using a pigtail catheter left to low suction or water seal is recommended. Secondary spontaneous pneumothorax Tube thoracostomy is the procedure of choice. ---------------------------------------- It is clearly important that treatment with high concentration oxygen should be avoided in patients with respiratory failure and in those with a tension pneumothorax. This method of treatment should probably be limited to the common primary type of spontaneous pneumothorax occurring in the absence of any generalized lung disease.
Computed tomography of the patient showing the pigtail ------------------------------------------------ The technique involves placing a small catheter either into the second anterior intercostal space in the midclavicular line or laterally at the fourth or fifth intercostal space in the anterior axillary line after local anesthesia and sterile preparation. A three-way stopcock is applied, and a 60-mL syringe is used to aspirate the pleural space until resistance is met and the patient coughs. The stopcock is closed, the tube is secured, and a chest radiograph is obtained to assure reexpansion. Aspiration of more than 4 L suggests continued air leak and failure of simple aspiration. Failure to fully expand warrants another aspiration attempt, addition of a Heimlich valve, or formal tube thoracostomy. If the procedure is successful, patients should be observed for 6 h and, if no recurrence is seen, the catheter is removed and the patient discharged with close follow-up within 24 h.
Secondary spontaneous pneumothorax Tube thoracostomy is the procedure of choice.
Iatrogenic pneumothorax: Aspiration is the technique of choice for iatrogenic pneumothoraces because recurrence usually is not a factor. Tube thoracostomy is reserved for very symptomatic patients.
Dr. Boney Cheriyan Thavalathil
Emergency Physician & Intensivist,
Normal pleural space = closed sac
in which negative pressure is
essential for normal lung expansion
What’s the normal pleural pressure?
Beginning of inspiration
- 5 cm H2O
End of inspiration
- 7.5 cm H2O
“Pneumo” – Gas
“Thorax” – Chest cavity
Occurs when air leaks into the space between the lungs
and chest wall, creating pressure against the lung
Chest wall defect
Altered Mental Status
Shift in mediastinum
Failure to reexpand
Persistent air leak
Removal of intrapleural air
Reexpansion pulmonary edema
Kinking of SVC & IVC
Decrease in Venous Return to heart
Decrease In C.O
SHOCK & HYPOPERFUSION
PO2 : decreased
Decreased from Hyperventilation
Elevated with respiratory compromise
Inspiratory & expiratory images
Underlying Pul. disease
Harder to detect
PSP – Blebs & Bullae
Assess the need for
Absence of “lung sliding” as assessed on the time-
Demonstration of a "lung point" on the time-motion
Absence of vertical comet-tail artifacts
95% sensitivity95% sensitivity
100% specificity100% specificity
Needle aspiration and small chest tube drainage
Elimination of intrapleural air
Optimization of pleural healing
Prevention of recurrences
Immediate decompression via
chest tube or needle
If a tension pneumothorax is
present, a “hiss of air” may be
heard escaping from the chest
Remove the needle,
leave the catheter in
Clear and manage the airway
Seal an open wound with an
Tape down three sides and create a flutter valve
Remote from the wound
Surgical closure of the wound
Pneumothorax is smaller than 15%
Patient is asymptomatic
Pneumothorax is smaller than 15%
Symptomatic & hemodynamically stable
Pneumothorax is greater than 15%
CT to evaluate need for thoracotomy
Thoracoscopy with stapling of blebs
Pleural abrasion & Sclerosing agent (Doxycycline or