The clinical presentation of tension pneumothorax is very similar to that of pneumothorax, even though it is much more pronounced. The classical signs include hypotension and hypoxia, the absence of sounds from the affected hemithorax and the deviation of the trachea away from the side of the affected chest. Furthermore, it is possible to observe hyperresonance in the thorax, tachycardia and a characteristic distension of the jugular veins.

Chest pain is very frequent, being present in the 90% of the cases, followed by dyspnea appearing in 80% of them. Less frequent signs include fatigue, anxiety, and the very rare epigastric pain.

• Dyspnea

  A 78-yr-old woman presented with progressing dyspnea. She had undergone an endoscopic retrograde cholangiopancreatogram three days before due to acute cholecystitis. [ncbi.nlm.nih.gov]

• Tracheal Deviation

  However, the classic physical examination findings of tracheal deviation and distended neck veins are poorly sensitive in the diagnosis of tension pneumothorax. [ncbi.nlm.nih.gov]

  Additional findings include severe respiratory distress, tracheal deviation away from the affected side, hypotension, and jugular venous distention. [medcomic.com]

  These patients typically experience significant respiratory distress and may also have: Tracheal deviation Unexplained hypotension Unilateral absence of breath sounds Presence of distended neck veins Hypertympanic percussion note over affected side. [webapp1.dlib.indiana.edu]

  Signs Unilateral absent breath sounds Hyperresonant chest to percussion Cyanosis Respiratory distress Tachycardia Hypotension Tracheal deviation to contralateral side Neck vein distention IV. [fpnotebook.com]

  As intrathoracic pressure increases, patients develop hypotension, tracheal deviation, and neck vein distention. The affected hemithorax is hyperresonant to percussion and often feels somewhat distended, tense, and poorly compressible to palpation. [merckmanuals.com]

• Hyperresonance

  The affected hemithorax is hyperresonant to percussion and often feels somewhat distended, tense, and poorly compressible to palpation. Tension pneumothorax should be diagnosed by clinical findings. [merckmanuals.com]

  Clinical Management Clinical features This is a clinican diagnosis History of penetrating trauma, positive pressure ventilation or airways disease Air hunger Hypotension ± distended neck veins ± hyperresonant on tension pneumothorax side Management Do [emed.ie]

  On the affected side, there is hyperresonance to percussion and decreased or absent breath sounds. Additional findings include severe respiratory distress, tracheal deviation away from the affected side, hypotension, and jugular venous distention. [medcomic.com]

  Signs Unilateral absent breath sounds Hyperresonant chest to percussion Cyanosis Respiratory distress Tachycardia Hypotension Tracheal deviation to contralateral side Neck vein distention IV. [fpnotebook.com]

  The classic clinical findings are: Hypotension Decreased or absent breath sounds on the affected side Hyperresonance to percussion Shift of the trachea away from the affected side Distended neck veins You should never diagnose a tension pneumothorax with [regionstraumapro.com]

• Decreased Breath Sounds

  Decreased breath sounds on the affected side were one of the most frequent clinical indications for NT, recorded in 28% of cases. Decreased breath sounds were more common in surviving than in nonsurviving patients. (37% v. 19%, p < 0.001). [ncbi.nlm.nih.gov]

  A chest examination revealed decreased breath sounds on the right side accompanied by resonance on percussion. [nejm.org]

  Definition Classic signs include decreased breath sounds, distended neck veins, and non-midline trachea. These are VERY uncommon. [openanesthesia.org]

  On exam, there is jugular venous distension, decreased breath sounds on the right side, with wheezes. A chest radiograph is obtained. [medbullets.com]

  Tension pneumothorax will typically present with decreased or absent breath sounds on the affected side. The trachea may be deviated to the opposite side. The patient will typically be tachycardic and hypotensive. [clinicaladvisor.com]

• Pulmonary Disorder

  Allergic Disorders Infectious Diseases Injuries; Poisoning Musculoskeletal and Connective Tissue Disorders Neurologic Disorders Nutritional Disorders Pediatrics Psychiatric Disorders Pulmonary Disorders Special Subjects Resources Videos Figures Images [msdmanuals.com]

• Hypotension

  He was clinically stable without hypoxia or hypotension, and the initial chest x-ray study showed a large pneumothorax without mediastinal shift. [ncbi.nlm.nih.gov]

  […] accumulation of air in pleural space - Respiratory distress, tachycardia, distended neck veins, cyanosis, asymmetry of chest wall motion - Tracheal deviation away from pneumothorax - Percussion hyperresonnance - Unilateral absence of breath sounds, hypotension [fprmed.com]

  More common changes suggestive of tension pneumothorax include hypotension, tachycardia, narrowing pulse pressure, and oxygen desaturation. Under anesthesia, these patients may exhibit a rise in airway pressures. Awake, they may become tachypnic. [openanesthesia.org]

• Chest Pain

  A 23-year-old Asian man was referred to the emergency room of Xiamen Chang Gung Memorial Hospital with a 1-day history of right-sided chest pain that had been aggravated for 1 hour. [ncbi.nlm.nih.gov]

• Tachycardia

  More common changes suggestive of tension pneumothorax include hypotension, tachycardia, narrowing pulse pressure, and oxygen desaturation. Under anesthesia, these patients may exhibit a rise in airway pressures. Awake, they may become tachypnic. [openanesthesia.org]

  Ventricular tachycardia developed, but a biphasic shock at 120 J immediately restored normal sinus rhythm. His vital signs, however, did not improve. [ncbi.nlm.nih.gov]

  Recognition of early signs and symptoms associated with tension pneumothorax, eg, progressive hypoxemia, tachycardia, and respiratory distress, can alert medical personnel to the need for rapid decompression before physiologic decompensation. [journals.lww.com]

  Common symptoms are an increase heart rate (tachycardia), an increased breathing rate (tachypnea) as well as a serious reduction of oxygen supply (hypoxia). [symptoma.com]

  Signs Unilateral absent breath sounds Hyperresonant chest to percussion Cyanosis Respiratory distress Tachycardia Hypotension Tracheal deviation to contralateral side Neck vein distention IV. [fpnotebook.com]

• Cyanosis

  Immediately Life-Threatening Chest Injuries Physical Exam Investigations Management Airway Obstruction - Anxiety, stridor, hoarseness, altered mental status - Apnea, cyanosis - Do not wait for ABG's to intubate - definitive airway management - intubate [fprmed.com]

  Signs Unilateral absent breath sounds Hyperresonant chest to percussion Cyanosis Respiratory distress Tachycardia Hypotension Tracheal deviation to contralateral side Neck vein distention IV. [fpnotebook.com]

  Signs of tension pneumothorax include increased difficulty in breathing, shortness of breath, cyanosis, and the trachea moving from its normal position toward the uninjured side of the chest. b. [brooksidepress.org]

  A two and a half week old male infant presents with a history of distressed noisy breathing for several hours, progressively worsening with periods of apnea and cyanosis. [dontforgetthebubbles.com]

• Fracture

  Multiple left rib fractures and a left lung laceration secondary to the use of the ACD device were also noted, although the pathologist felt that the tension pneumothorax had not contributed to the patient's death. [ncbi.nlm.nih.gov]

  each at 2 sites - Underlying lung contusion (cause of morbidity and mortality) - paradoxical movement of flail segment - palpable crepitus of ribs - decreased air entry on affected side - ABGs : decreased pO 2, increased pCO 2 - CXR : rib fractures, [fprmed.com]

  The etiological factors of tension pneumothorax can be both iatrogenic and related to a trauma, such as an explosion or a penetrating traumatic event, which then causes the disruption of the pleura usually in association with a rib fracture. [symptoma.com]

  He has an obvious open fracture of his right forearm. He also has decreased air entry to the right side of his chest. The team will need to recognize the tension pneumothorax as part of their primary survey. [emsimcases.com]

  though rib fractures are not necessary for tension pneumothorax to occur. [emedicine.medscape.com]

The diagnosis of tension pneumothorax is largely based on the use of imaging studies, which should be performed promptly to avoid further complications of this medical emergency. If the use of radiography is considered, the time to obtain imaging studies should be balanced against the expected clinical course. Findings usually include increased thoracic volume, trachea deviation and ipsilateral lung collapse. Moreover, the intercostals spaces appear widened and heart border flattened on the affected side.

CT scan is very reliable as diagnostic technique, but it is not recommended for routine use. Anyway, it provides a series of advances, such as the possibility of distinguishing a large bulla from a case of pneumothorax, underlying the presence of emphysema or emphysema-like changes, or determining the side of the pneumothorax. It can also be used to detect the presence of concomitant pulmonary diseases, because of the greater quality of the images provided by it. Ultrasonography, instead, can be used as a valid alternative to CT scan for patients with very unstable conditions, without compromising the sensitivity, specificity, and effectiveness of the diagnosis itself.

• Mediastinal Shift

  He was clinically stable without hypoxia or hypotension, and the initial chest x-ray study showed a large pneumothorax without mediastinal shift. [ncbi.nlm.nih.gov]

  If not relieved, it can lead to lung collapse and mediastinal shift. [medical-dictionary.thefreedictionary.com]

• Atelectasis

  There is no air in the pleural space normally The introduction of air into the pleural space separates the visceral from the parietal pleura In contradistinction, the visceral and parietal pleura usually do not separate from each other in obstructive atelectasis [learningradiology.com]

  An elevated hemidiaphragm implies volume loss in that hemithorax due to atelectasis, hypoplasia or a diaphragmatic hernia. A decubitus film can demonstrate failure of the emphysematous lobe to deflate when placed down. [dontforgetthebubbles.com]

The classical treatment for tension pneumothorax is the chest decompression through needle thoracostomy, performed by inserting an intravenous cannula into the second rib space in the mid-clavicular line. The needle is pushed down until air can be aspirated into a syringe attached to the needle itself. Once the needle is withdrawn leaving the cannula opened, a rush of air comes out of it indicating the presence of the condition. With the pressure gradually decreasing dueto this maneuver, tension pneumothorax slowly turns into simple pneumothorax. In any case, many experts suggest that this methodology might be ineffective, and tension might even re-accumulate after the clinical procedure. Furthermore, the formation of air embolism from the lung laceration is highly possible. For these reasons, it is strongly recommended to wait for the diagnostic results before carrying out this clinical procedure.

Frequently used as definitive treatment for tension pneumothorax is chest tube placement. This procedure is often preferred by clinicians, because it is very rapid and allows a controlled intervention much safer than the blind needle thoracostomy, even though it takes a little bit longer to complete. These surgical procedures are also coupled with pharmacotherapy whose main purpose is to reduce morbidity and prevent complications. The main medications employed include anesthetics, analgesics, and antibiotics.

The prognosis of tension pneumothorax depends of the promptness of treatment. In fact, if not recognized and treated on time, tension pneumothorax swiftly progresses to respiratory insufficiency, cardiovascular collapse and finally death. This is the reason why immediate treatment is paramount, to be performed before the appearance of any signs of hemodynamic instability.

The etiological factors of tension pneumothorax can be both iatrogenic and related to a trauma, such as an explosion or a penetrating traumatic event, which then causes the disruption of the pleura usually in association with a rib fracture. Other possible situations from which tension pneumothorax can occur might also include:

• Barotrauma secondary to positive-pressure ventilation
• Thoracic spine fractures
• Colonoscopy [3]
• Acupuncture [4] [5] [6]
• Percutaneous tracheostomy [7]

Tension pneumothorax often occurs in a hospital setting, especially when subjects are under intensive care treatment undergoing ventilation with positive pressure.

There is not a validate estimate regarding the incidence of tension pneumothorax, and its value still has to be officially determined. In any case, experts believe that this condition occurs in 5% of those affected by a chest trauma, and under control in a pre-hospital setting, and from 1% to 3% of adults under intensive care [8] [9] [1] [10]. According to a retrospective cohort study, the mechanically ventilated patients affected by tension pneumothorax have a risk of death which is around 38 times higher than those who are not affected [11] and show no sign of possible chest over-tension.

It is difficult to determine the incidence of tension pneumothorax outside hospital settings. A possible estimate could be given by the review of military deaths from thoracic trauma, which seems to suggest that up to 5% of the combat casualties showing thoracic trauma showed this condition at the moment of death [12]. In any case, these data come from a setting of war, which do not necessarily represent a “normal” situation.

As previously said, tension pneumothorax usually occurs after a traumatic event which causes a laceratio, such as the already mentioned explosion, barotrauma secondary to positive-pressure ventilation, pneumoperitoneum, thoracic spine fractures, acupuncture, and colonoscopy. Other possible causes include:

• Fiberoptic bronchoscopy with closed-lung biopsy [13]
• Pneumoperitoneum [14] [15]
• Percutaneous tracheostomy [16]

Furthermore, tension pneumothorax is particularly frequent among those requiring ventilatory assistance or undergoing meconium aspiration, since aspirated meconium might work as a 1-way valve causing the condition. It is also particularly interesting to notice the presence of acupuncture among the etiological factors, which is responsible of around 1 over 5000 cases of tension pneumothorax [17].

The most important preventive measure to avoid tension pneumothorax is to stop smoking, so that the occurrence of an underlying episode of pneumothorax can be prevented. If a patient show a history of pneumothorax or tension pneumothorax, he/she is also strongly recommended to avoid scuba diving, which might cause dangerous pressure changes. Furthermore, it is recommended to wear seatbelt when driving or being in a motor vehicle, so that accident-related trauma can be prevented as much as possible.

The word pneumothorax refers to the presence of gas or air within the pleural space. In the case of tension pneumothorax (TP), air escapes from the lung into the pleural space, creating an increasingly higher pressure in what can be defined as a one-way-valve effect. The progressive build-up of air and pressure pushes the mediastinum to the opposite hemithorax, creating the conditions for obstructing venous return to the heart. The possible outcome is a circulatory instability which then results in traumatic arrest. Although there are many definitions, experts tend to consider TP as the condition in which pneumothorax leads to significant impairment of respiration, blood circulation and possibly death [1].

The classical signs of this life-threatening condition is an over-expanded chest that moves very little with respiration, together with depression of the hemidiaphragm and an alarmingly increased percussion note. Moreover, it is also possible to observe a deviation of the trachea away from the side affected by the tension. Patients usually appear tachycardic, tachypnoeic, and possibly hypoxic. After the appearance of these first signs, it is also possible to observe circulatory collapse with hypotension and subsequently traumatic arrest showing pulseless electrical activity (PEA).

Tension pneumothorax might develop especially in the presence of positive pressure ventilation, and after a while it is not difficult to appreciate how the circulatory functions are compromised by this tension. In the end, the condition causes steadily worsening oxygen shortage and low blood pressure, which might result in death. For these reasons, it can be considered as a life-threatening emergency requiring immediate clinical attention [2].

Tension pneumothorax is defined as a continuous build-up of air within the pleural space between the lungs and the chest, creating an increasing pressure in the chest. The possible outcome of this pathological condition are circulatory instability, respiratory and cardiac problems, which if not promptly treated might cause the death of the affected subject.

The classical signs of this life-threatening condition are an over-expanded chest that moves very little with respiration, together with depression of the hemidiaphragm (the muscle separating the chest cavity from the abdomen). Common symptoms are an increase heart rate (tachycardia), an increased breathing rate (tachypnea) as well as a serious reduction of oxygen supply (hypoxia). If the conditions lasts for long enough it might finally result in circulatory collapse, hypertension, traumatic arrest and death. For these reasons tension pneumothorax is considered a life-threatening emergency requiring immediate clinical attention.

The classical cause of tension pneumothorax is a traumatic event, such as a motor-vehicle accident or a surgical procedure like colonoscopy or acupuncture. The treatments for this condition include the aspiration of air with the help of a needle (needle thoracostomy) or with the help of a tube (chest tube placement). The latter is more frequently used because it is much safer and much more rapid, even though it takes a little bit longer to complete. Several medications are also used to avoid further complications like infection, and these include anesthetics, analgesics, and antibiotics.

The most important preventive measure to avoid tension pneumothorax is to stop smoking, so that the occurrence of an underlying episode of pneumothorax can be prevented. If a patient show a history of pneumothorax and tension pneumothorax, he/she is also strongly recommended to avoid scuba diving, which might cause dangerous pressure changes. Furthermore, it is recommended to wear seatbelt when driving or being in a motor vehicle, so that accident-related trauma can be prevented as much as possible.

1. Leigh-Smith S, Harris T. Tension pneumothorax—time for a re-think?. Emergency Medicine Journal 2005 22 (1): 8–16. 
2. MacDuff A, Arnold A, Harvey J, BTS Pleural Disease Guideline Group. Management of spontaneous pneumothorax: British Thoracic Society pleural disease guideline 2010. Thorax 2010 65 (8): ii18–ii31. 
3. Hearnshaw SA, Oppong K, Jaques B, Thompson NP. Tension pneumothorax as a complication of colonoscopy. Endoscopy. Feb 2004;36(2):190. 
4. Peuker E. Case report of tension pneumothorax related to acupuncture. Acupunct Med. Mar 2004;22(1):40-3.
5. Whale C, Hallam C. Tension pneumothorax related to acupuncture. Acupunct Med. Jun 2004;22(2):101; author reply 101-2.
6. Zhao DY, Zhang GL. [Clinical analysis on 38 cases of pneumothorax induced by acupuncture or acupoint injection]. Zhongguo Zhen Jiu. Mar 2009;29(3):239-42. 
7. Brander L, Takala J. Tracheal tear and tension pneumothorax complicating bronchoscopy-guided percutaneous tracheostomy. Heart Lung. Mar-Apr 2006;35(2):144-5. 
8. Ludwig J, Kienzle GD: Pneumothorax in a large autopsy population. A study of 77 cases. Am J Clin Pathol 1978, 70:24-26.
9. Coats TJ, Wilson AW, Xeropotamous N: Pre-hospital management of patients with severe thoracic injury. Injury 1995, 26:581-585. 
10. Kumar A, Pontoppidan H, Falke KJ, Wilson RS, Laver MB: Pulmonary barotrauma during mechanical ventilation. Crit Care Med 1973, 1:181-186. 
11. Chen KY, Jerng JS, Liao WY, Ding LW, Kuo LC, Wang JY, Yang PC: Pneumothorax in the ICU: patient outcomes and prognostic factors.vChest 2002, 122:678-683. 
12. McPherson JJ, Feigin DS, Bellamy RF. Prevalence of tension pneumothorax in fatally wounded combat casualties. J Trauma. Mar 2006;60(3):573-8. 
13. Iannoli ED, Litman RS. Tension pneumothorax during flexible fiberoptic bronchoscopy in a newborn. Anesth Analg. Mar 2002;94(3):512-3; table of contents. 
14. Miller JS, Itani KM, Oza MD, Wall MJ. Gastric rupture with tension pneumoperitoneum: a complication of difficult endotracheal intubation. Ann Emerg Med. Sep 1997;30(3):343-6. 
15. Hashmi S, Rogers SO. Tension pneumothorax with pneumopericardium. J Trauma. Jun 2003;54(6):1254. 
16. Brander L, Takala J. Tracheal tear and tension pneumothorax complicating bronchoscopy-guided percutaneous tracheostomy. Heart Lung. Mar-Apr 2006;35(2):144-5. 
17. Yamashita H, Tsukayama H, Tanno Y, Nishijo K. Adverse events related to acupuncture. JAMA. Nov 11 1998;280(18):1563-4.