A 37-year-old male has been admitted to your ICU following an explosion in his garage. He has suffered a mixture of partial and deep burns estimated at 35% total body surface area, and has been intubated in the Emergency Department. After one hour of resuscitation in your unit he remains hypotensive with a blood pressure of 80/50 mmHg.
List the potential causes and outline how you would diagnose and manage them.
1. Spurious
i. Increase fluid resuscitation rate
a. Review/repeat trauma imaging
i. Blood product resuscitation, correction of coagulopathy ii. Operative/Interventional radiology interventions to treat cause
i. Mixed venous oxygen, empirical antidote administration
Cardiogenic
b. Abdominal compartment syndrome
i. Bladder pressure, escharotomies, laparotomy/laparostomy
c. Tamponade
i. Echo and pericardiocentesis
Examiners comments:
Most candidates were not able to amalgamate the three crucial aspects of this patient i.e., trauma in a burns patient in the setting of a closed area explosion.
Many focused solely on the burns with little reference to the trauma.
Many used a generic ABCD template without applying it to the patient.
Many answer structures were haphazard with an initial list of the causes followed by the management, with the result that the management for a number of the differentials were missed.
The best answers used a table or bulleted list approach taking about causes as well as management.
Though the college describes this as an "explosion", it is highly unlikely that this patient was exposed to a blast wave (as usually household explosions are of the deflagration variety) and so the discussion will focus mainly on the investigations and management of burns-related hypotension. Blast injury is mentioned in the list as an aside, in response to the comment that most answers "focused solely on the burns with little reference to the trauma".
Thus:
Possible causes of shock in this patient (table adapted from "Causes of Shock in the Trauma Patient")
Type of shock | Cause | Diagnostic strategy |
Artifact of measurement | Blood pressure measurement is inaccurate |
|
Cardiogenic | Cardiac contusion (blast) |
|
Myocardial infarction |
|
|
Arrhythmia |
|
|
Obstructive | Cardiac tamponade |
|
Tension pneumothorax |
|
|
Fat embolism (blast) |
|
|
Neurogenic | Spinal injury |
|
Hypovolemic | Massive blood loss |
|
Massive fluid shift |
|
|
Distributive | Anaphylaxis (induction drugs) |
|
Management, therefore, will consist of the following steps:
Moore, Francis D., et al. "The role of exudate losses in the protein and electrolyte imbalance of burned patients." Annals of surgery 132.1 (1950): 1.
Latenser, Barbara A. "Critical care of the burn patient: the first 48 hours." Critical care medicine37.10 (2009): 2819-2826.
Asch, MORRIS J., et al. "Systemic and pulmonary hemodynamic changes accompanying thermal injury." Annals of surgery 178.2 (1973): 218.
Crum, Ralph L., et al. "Cardiovascular and neurohumoral responses following burn injury."Archives of Surgery 125.8 (1990): 1065-1069.