In this CritCases blog, Shock and Hypoxia in Blunt Chest Trauma, a collaboration between STARS Air Ambulance Service, Mike Betzner and EM Cases, Mike Misch guides us through a hairy chest trauma case, reviewing principles of trauma resuscitation, airway considerations, tension pneumothorax management and a rare and challenging chest trauma diagnosis…

Written by Mike Misch. Edited by Anton Helman. January 2020.

A 26-year old male is involved in a high-speed, single vehicle MVC. He required extrication by paramedics who reported significant damage to the vehicle. Initial vitals on scene were T 37.0, HR 130 bpm, BP 90/40, RR 38, O2 Sat 78%, up to 88% with a non-rebreather. GCS is 12. A bolus of crystalloid is started and the patient is brought into your emergency department. You work in a regional centre with general and thoracic surgery. But you are not a trauma center, nearest trauma center is 50 mins by flight.

Primary survey reveals a patent airway without stridor or signs of blunt or penetrating injury. Patient is in a C-collar. There is vomitus on the patient’s face and chest. There is significant ecchymosis of the chest bilaterally and subcutaneous emphysema on the left. Abdomen is soft without ecchymosis.

 

What are your immediate initial management priorities? Does this patient first need to be intubated?

Rigid adherence to the ABCDE of ATLS overemphasizes the immediate need for intubation prior to other intervention. However, this patient is in a shock state. Pre-intubation hypotension, particularly with a Shock Index (systolic HR/BP) > 1 is associated with post-intubation cardiac arrest. While the patient will likely require intubation in anticipation of clinical course, in the absence of critical hypoxia or a dynamic airway (blunt, penetrating or burn injuries of the face and neck), your immediate priority should be identifying and addressing the cause of the patient’s shock.

The patient has decreased breath sounds bilaterally, abdomen is soft, FAST exam is negative, including absent pericardial effusion, but on the extended study there is absent lung sliding bilaterally. You can’t appreciate distended neck veins, but you can appreciate that the trachea is deviated to the right. These findings are the basis for the presumptive diagnosis of bilateral pneumothoraces with a tension pneumothorax on the left.

 

How are you going to decompress the pneumothoraces in this blunt chest trauma?

Traditional teaching involves placing a large gauge angiocatheter in the second intercostal space, mid-clavicular line. More recently, the 5th intercostal space, mid-axillary line is thought to be the preferred site, especially in obese patients. That being said, needle thoracostomy alone is successful in decompressing pneumothoraces less than half the time. As such, many experts recommend a finger thoracostomy, as the operator is able to confirm entrance into the thoracic cavity with their finger.

You make a 2-3 cm incision on the left 4th intercostal space, use curved Kelly forceps to puncture through intercostal muscles and obtain a gush of air. You use your finger to confirm communication with the pleural space. The patient’s heart rate immediately decreases from 130 to 110 bpm, Oxygen saturation improves to 92% on the rebreather and BP remains 90/40. You repeat the same on the left with another gush of air returned. You insert two 32 F chest tubes and attach both to water seal. Chest X-Ray confirms bilateral rib fractures and pneumothoraces with chest tubes in acceptable position. Trauma blood work is sent, the patient is given 1.5 g of TXA and you call for 2 units of O positive blood from your blood bank. You decide to intubate using RSI prior to CT.

 

What drugs will use for RSI in this case with shock and hypoxia from blunt chest trauma?

In shock states, all sedative agents will cause some degree of hypotension. Maximizing pre-load (ideally with blood products in this case) will minimize the chance of post-intubation hypotension. Using ketamine at no more than 50% of the usual dose (0.5 mg/kg) is preferred by most experts. Unlike sedatives which require lower doses in shock states, paralytics require a higher dose as they must get to the neuromuscular junction to provide paralysis. Most authors recommend doses of rocuronium of 1.2-1.6 mg/kg in shock states.

 

In shock RSI decrease the ketamine dose to 0.5mg/kg max and increase the rocuronium dose to 1.2-1.6mg/kg.

 

You have the patient on flush oxygen (~40 L/min via a non-rebreather) for 4 minutes. You start insfusion of a unit of red cells via a rapid infuser. Pre-intubation oxygen saturation is 90%. You give ketamine 40 mg IV push followed by 120 mg of rocuronium. You decide to use video laryngoscopy (VL) with a nurse providing inline C-spine stabilization. The oropharynx is full of vomit which immediately obscures your view.

 

How can you optimize your view?

The Suction Assisted Laryngoscopy Airway Decontamination (SALAD) approach has been devised by Jim Decanto (https://openairway.org) to aide in intubation of the massively soiled airway. He describes using a rigid large-bore suction catheter to initially decontaminate the soiled airway https://openairway.org/salad/.

Steps of the SALAD approach

  1. Setup like you are preparing to intubate with the suction in the right hand, laryngoscope in your left (assuming you are right-handed)
  2. Advance the suction into the glottis to clear the upper airway of secretions before inserting the laryngoscope.
  3. Advance the laryngoscope into the oropharynx, keeping the blade as anterior as possible, hugging the tongue to avoid submersing the camera of your VL into the blood/mucus
  4. Use the VL view to guide further decontamination of the glottis
  5. Advance the suction tip into the esophagus to prevent further spill-over of contaminants into the pharynx
  6. Reposition handle of suction catheter to left side of patient’s mouth and pin it in place using the laryngoscope in your left hand
  7. Insert the endotracheal tube and inflate the cuff.

While a Yankauer suction catheter was never designed to suction copious upper airway secretions it has somehow become the first-line suction available in our resuscitation rooms. Large-bore suction catheters specifically designed for clearing large amount of fluids from the airway are available but may not be in your ER. A large-bore catheter can be made using an ETT and a meconium aspirator (https://emcrit.org/emcrit/ett-as-suction-device/) or using a suction tubing and a stylet (https://emcrit.org/pulmcrit/large-bore-suction/).

 

The Patient is intubated with temporary desaturation to 86%. EtCO2 confirms placement. The patient is brought to the CT scanner. While in the scanner, the patient desaturates to the 70s. He is rushed back to the trauma bay before the scan can be completed. He is again tachycardic at 130 bpm, blood pressure 85/30. You see his trachea is definitely deviated to the right again, and there is now obvious jugular venous distension.

What is going on? What’s your next move?

The patient is again presenting with a tension pneumothorax.

You confirm that the chest tube is still in position and connected to water seal, but now there is continuously (ie. both inspiratory and expiratory) a large amount of bubbling at the Water Seal Chamber.  

 

What does continuous bubbling at the water seal suction signify?

Bubbling at the water seal suction can be expected during the expiratory phase in a patient with a recently inserted chest tube. Continuous bubbling during both inspiration and expiration suggests two things:

  1. The leak is coming from the chest tube system, requiring simply replacement of the water seal suction device
  2. The leak is coming from the patient, requiring some significant and timely interventions

 

How can you differentiate the two causes of continuous air leak at the bedside?

Clamp the chest tube proximally as it exits the patients dressing – if the continuous bubbling persists – the leak is from the water seal. If the bubbling stops, the system leak is coming from the patient ie: a massive air leak due to a bronchopleural fistula or large lung laceration.

Remember, the patient is in tension, so only clamp the tube for a second or two to determine whether bubbling ceases or not.

 

Clamping the tube at the skin causes immediate ceasing of bubbling at the water seal.

 

What is the most likely diagnosis?

This patient has a significant air leak, in the context of trauma – this is very worrisome for a bronchopleural fistula (BPF) – a pathologic communication between the bronchial tree and the pleural space. BPFs are a feared complication of various forms of lung pathology and are associated with mortality as high as 50%. The most common cause of BPF is a complication of surgical lung resection, but can also occur as a complication of severe lung infections, lung malignancies and less likely thoracic trauma. While, subacute presentations exist, when it occurs acutely, as in traumatic causes, the presentation is dramatic and that of a tension pneumothorax:

  • Acute hypoxia and hypotension
  • Deviation of the trachea and mediastinum
  • Jugular venous distention
  • Persistent air leak (demonstrated by ongoing bubbling at the water seal chamber)

 

You suspect the patient has a traumatic bronchopleural fistula, with ongoing air leak and tension physiology despite a well-positioned chest tube. What are your next steps?

You need to place another chest tube. This patient likely has a massive air leak that is causing recurrent tension pneumothorax. While there is increasing evidence the smaller (18G- 24G) chest tubes are sufficient in the majority of trauma patients, the larger the chest tube the better in this case.

 

You perform another finger thoracostomy in the 4th intercostal space. A gush of air is returned. You insert a 32 F chest tube. Chest X-Ray (below) confirms chest tube placement – 2 on the left in good position; chest tube on the right position not ideal but is acceptable. You call your regional trauma team for transfer, but it is determined that the patient is “too sick” for transport at this time.

CXR bronchopulmonary fistula

Portable Chest X-Ray post second chest tube on the left.

 

The patient then returns to DI to complete the pan-scan. Shortly after returning from the scanner, the radiologist calls you. CT shows no intra-abdominal or intracranial injury. There are multiple rib fractures with extensive pulmonary contusions bilaterally, more so on the left, with bilateral hemopneumothoraces. The radiologist tells you there’s still deviation of the mediastinum to the right. Looking back at the Chest X-Ray obtained post second chest tube insertion, you realize this also showed over-inflation of the left lung with shift of the mediastinum.

Repeat Vitals: HR 110, systolic BP 80-90, Oxygen Sat 85%. You note that there is still continuous bubbling at the water seal, which again stops with clamping of the chest tube at the patient.

 

There’s no obvious hemorrhagic cause for the patient’s shock. This patient is still presenting as a tension pneumothorax despite 2 chest tubes on the left. What’s next?

You call your thoracic surgeon on call who happens to be in hospital. He recommends a third chest tube on the left side as a temporizing measure as this patient will likely require an emergency thoracotomy to repair the fistula if his hemodynamics do not improve. He also suggests this patient may need ECMO. In the meantime, you place a third chest tube on the left side in the 5th intercostal space.  You call the transport team and tertiary center, but there is ongoing concern about the patient’s stability for transport. You call your anesthesiologist to help with managing the patient on the ventilator and in case the patient might need to go to the OR for a thoracotomy.

 

How are you going to stabilize this patient with a bronchopleural fistula enough for transfer to the trauma center?

To find out how the experts manage this patient with a bronchopleural fistula and safely transfer the patient go to Part 2 published January 28th, 2020.

 

References for Diagnosis of Bronchopleural fistula

Kim WY, Kwak MK, Ko BS, et al. Factors associated with the occurrence of cardiac arrest after emergency tracheal intubation in the emergency department. PLoS One 2014;9(11):e112779.

Kovacs G, Sowers N. Airway Management in Trauma. Emerg Med Clin North Am. 2018;36(1):61-84.

Lois M, Noppen M. Bronchopleural fistulas: an overview of the problem with special focus on endoscopic management. Chest. 2005;128(6):3955-65.

Petrosoniak A, Hicks C. Resuscitation Resequenced: A Rational Approach to Patients with Trauma in Shock. Emerg Med Clin North Am. 2018;36(1):41-60.

Schellenberg M, Inaba K. Critical Decisions in the Management of Thoracic Trauma. Emerg Med Clin North Am. 2018;36(1):135-147.

Shekar K, Foot C, Fraser J, Ziegenfuss M, Hopkins P, Windsor M. Bronchopleural fistula: an update for intensivists. J Crit Care. 2010;25(1):47-55.