UBP 4.2 (Long Form): Trauma & Burn

Question 1

Intra-Operative Management:

Which monitors would you require for this case?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 1

In addition to the standard ASA monitors, I would place –

1. a 5-lead EKG to monitor for myocardial ischemia
   
   • (may require needle electrodes with burns on the chest);
2. an arterial line to facilitate frequent arterial blood gas measurements and closely monitor the hemodynamics of this acidotic patient at risk for major fluid shifts;
3. a central line to follow central venous pressure, facilitate fluid resuscitation, and provide access for a pulmonary artery catheter (should it be required);
4. a Foley catheter to help monitor fluid resuscitation and assess the renal function of this patient at increased risk of acute renal failure secondary to hypovolemia or rhabdomyolysis; and
5. a core body temperature probe to monitor temperature and avoid hypothermia. If I believed the patient’s hemodynamic status might significantly limit the amount of anesthetic I could deliver, I would consider using –
6. a bispectral index monitor (BIS) and attempt to titrate my anesthetic to an index < 60 to prevent recall.

In addition to these monitors, I would require –

• at least two large-bore intravenous lines,
• a rapid infusion device, and
• equipment useful in preventing hypothermia, such as –
  
  • warming blankets, heat lamps, and intravenous fluid warmers.

Question 2

Intra-Operative Management:

The medical students asks you what cardiovascular changes you expect to occur following a significant burn injury.

What would you tell her?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 2

In the immediate post-burn period (first 24-48 hours),

cardiac output is decreased due to –

• circulating myocardial depressant factors,
• increased systemic vascular resistance,
• a contracted plasma volume (due to increased capillary permeability leading to the movement of protein-rich fluid from the intravascular to the interstitial space),
• decreased coronary blood flow, and
• a diminished response to catecholamines.

If fluid resuscitation has been adequate, the patient’s capillary integrity returns to normal after 24-48 hours.

Moreover, interstitial fluid re-absorption, increased metabolic demands, and increased circulating catecholamines lead to –

a hyperdynamic state, where –

• cardiac output is increased (2 X normal) and
• systemic vascular resistance is reduced (the latter may be the result of circulating inflammatory mediators).

Question 3

Intra-Operative Management:

In the process of transferring the patient to the operating room bed, he is accidentally extubated. You quickly reposition him on the OR bed, place an oral airway, apply the oxygen mask, and are unable to ventilate.

What are you going to do?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 3

Recognizing that the most likely cause of my inability to ventilate is –

• laryngospasm
  
  • (possibly due to light anesthesia, stimulation from ETT pulled through airway, and/or aspiration),
• airway swelling
  
  • (due to burn/inhalational injury),
• the tissue obstruction associated with obstructive sleep apnea, or
• a combination of these complications,

I would proceed as follows:

1. call for the difficult airway cart and a surgeon capable of performing an emergency tracheostomy;
2. ensure adequate manual in-line stabilization;
3. have someone apply cricoid pressure, making sure that the c-collar or a hand behind the neck are in place to prevent cervical spine movement;
4. eliminate any foreign material or secretions from the oropharynx
   
   • (these can stimulate the superior laryngeal nerve with a subsequently exaggerated reflex glottic closure – laryngospasm);
5. provide jaw thrust and apply firm pressure at the ascending ramus of the mandible, a maneuver believed to relieve laryngospasm (Larson’s maneuver);
6. initiate gentle positive pressure ventilation using 100% oxygen
   
   • (acts as a pneumatic splint);
7. deepen the anesthetic and administer intravenous lidocaine (1.0-1.5 mg/kg), in the hopes that this will blunt any exaggerated glottic closure reflex; and
8. place the patient in a 30° reverse-trendelenburg position to facilitate rapid intubation and help relieve the tissue obstruction associated with obstructive sleep apnea and/or tissue swelling.

If the patient remained apneic and none of these measures proved successful in facilitating assisted ventilation, I would consider administering –

• a small dose of intravenous succinylcholine (0.1-0.5 mg/kg) to relieve any laryngospasm and to facilitate the placement of an endotracheal tube.

If intubation was unsuccessful, I would –

• place an LMA and
• have the surgeon begin preparations for emergent cricothyrotomy or tracheostomy.

Question 4

Intra-Operative Management:

Assuming this was laryngospasm, would succinylcholine be contraindicated in this burn patient?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 4

Due to a potentially lethal increase in serum potassium,

the use of succinylcholine is contraindicated in burn patients after the first 24 hours following burn injury, and for as long as 1-2 years following complete healing of all burned skin.

(How about for spinal cord injury? – 6 months = decreased risk)

The up-regulation of extra-junctional cholinergic receptors believed to be responsible for this exaggerated hyperkalemic response to succinylcholine –

• does not occur until 24-48 hours after the burn injury,
• is most pronounced 5 to 15 days following the burn,
• may persist for an extended period of time,
• has resulted in serum potassium levels as high as 13 mEq/L, and
• can lead to ventricular tachycardia, fibrillation, and cardiac arrest.

Therefore, assuming his injury did not occur over 24 hours ago, the use of succinylcholine would not be contraindicated.

However, considering the increased risk for difficult intubation and/or ventilation in this case, I would only utilize succinylcholine as a treatment of last resort (i.e. persistent laryngospasm).

Question 5

Intra-Operative Management:

You manage to secure the airway and the surgery begins.

Following fasciotomy, the patient suddenly loses 850 mL of blood.

Would you begin blood transfusion?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 5

(UBP Live Notes – Point of this question – EBL calculation)

Given this patient’s history of HTN, IDDM, hypercholesterolemia, and CO level of 20% (left-ward shift of the hemoglobin dissociation curve and displacement of oxygen from hemoglobin due to 200-fold greater affinity),

I would prefer to maintain his hematocrit above 30%.

However, in addition to an estimated allowable blood loss, my decision to transfuse would be based on –

• current surgical hemostasis,
• hemodynamic stability, and
• any signs of tissue ischemia or inadequate organ perfusion.

An estimated allowable blood loss could be calculated by subtracting my selected minimum Hct of 30% from his preoperative Hct of 33%, multiplying this by his estimated blood volume (75 mL/kg x 96 kg = 7,200 mL), and dividing this number by his preoperative Hct of 33%, to obtain an estimated allowable blood loss of around 650 mL.

Therefore, assuming adequate surgical hemostasis, normal coagulation, and hemodynamic stability, I would begin by transfusing 1-2 units of PRBCs and then re-evaluate the patient.

Note: EBL for Parturient is like a neonate = 90 - 100 mL/kg

Question 6

Intra-Operative Management:

The surgeon decides to use an intramedullary rod fixated with bone cement to repair the fracture. During rodding of the femoral shaft the SpO2 suddenly drops to 88% and the blood pressure falls to 76/50 mmHg.

What do you think is the cause?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 6

The sudden development of hypoxia and hypotension during rodding of the femoral shaft using methyl methacrylate is consistent with –

1. fulminant fat embolism syndrome
   
   • (fat embolism may have occurred following the long bone fracture and/or with placement of the intra-medullary device in the femoral shaft) and/or
2. bone-cement implantation syndrome
   
   • (the use of methyl methacrylate can lead to circulating methyl methacrylate monomer and the embolism of intra-medullary debris).

However, I would also consider other potentially life-threatening causes, such as –

1. tension pneumothorax
   
   • (trauma, line placement),
2. cardiac tamponade
   
   • (trauma, increased capillary permeability, and aggressive fluid resuscitation),
3. significant hemorrhage
   
   • (occult abdominal, thoracic, or extremity bleeding, coagulopathy, inadequate surgical hemostasis),
4. dysrhythmia, and
5. myocardial ischemia.

To further my diagnosis, I would –

• auscultate all lung fields;
• observe the surgical field and estimate blood loss;
• evaluate the EKG;
• place a pulmonary artery catheter; and
• order a hemoglobin, hematocrit, and coagulation profile.

If the diagnosis were still in doubt, I would consider –

• an abdominal and thoracic ultrasound to identify occult bleeding, and
• transesophageal echocardiography to identify –
  
  • pericardial effusion,
  • cardiac tamponade (compression of the right heart, leftward displacement of the ventricular septum),
  • wall motion abnormalities (myocardial ischemia), or
  • intra-medullary debris in the right heart (fat embolism and/or bone-cement implantation syndrome).

Question 7

Intra-Operative Management:

What is the pathophysiology of bone-cement implantation syndrome?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 7

There are several mechanisms by which the hypotension, hypoxia, dysrhythmias, pulmonary hypertension, decreased cardiac output, and even cardiac arrest associated with bone-cement implantation syndrome may develop.

• First, the hardening and expansion of the bone cement results in increased intra-medullary pressures and the embolization of bone marrow debris.
  
  • When these emboli are of sufficient size or quantity, they can lead to increased pulmonary vascular resistance, right ventricular strain, and ventricular dysfunction.
• Second, circulating methyl methacrylate monomer may lead to reduced systemic vascular resistance.
• And third, the release of cytokines during reaming of the femoral canal may lead to microthrombus formation and pulmonary hypertension.

The effects of bone-cement implantation syndrome may be ameliorated by –

• maintaining euvolemia,
• creating a vent hole in the femur prior to implantation to relieve intramedullary pressures,
• performing high-pressure pulsatile lavage of the femoral canal to remove debris, or
• by avoiding the use of bone-cement.

Question 8

Intra-Operative Management:

If you believed his hypotension were due to bone-cement implantation syndrome, what would you do?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 8

Recognizing that the treatment of bone-cement implantation syndrome is largely supportive, I would –

provide 100% oxygen and administer fluids and vasopressors as indicated.

While the administration of corticosteroids may be beneficial, the current evidence is inconsistent and, considering the effects of steroids on glucose homeostasis, I would avoid their administration in this patient with insulin dependent diabetes mellitus.

Moreover, treatment with heparin and alcohol has NOT been demonstrated to improve outcome, and is NOT recommended.

Question 9

Post-Operative Management:

You transport the patient to the ICU.

Two hours later the nurse calls to report that the cuff on the endotracheal tube is ruptured and they are unable to ventilate adequately.

What would you do?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 9

First, I would –

1. evaluate the adequacy of the patient’s airway, ventilation, level of sedation, and ventilator settings.

Assuming the nurse’s assessment was correct, I would prepare to replace the patient’s endotracheal tube.

Given his massive burn, aggressive fluid resuscitation, recent airway manipulation, probable inhalational injury, rapid metabolism, bone-cement implantation syndrome, and diagnosis of obstructive sleep apnea, I would be very concerned about –

• the potential for airway obstruction,
• rapid-de-saturation,
• an inability to ventilate,
• difficult laryngoscopy,
• prolonged hypoxia, and even death.

Therefore, I would –

1. obtain the appropriate difficult airway equipment, including various sizes of endotracheal tubes;
2. ensure the presence of a surgeon capable of performing emergent tracheostomy;
3. have the neck prepped and draped ;
4. ensure adequate sedation, and
5. replace the endotracheal tube using a jet-ventilation exchange catheter. (Know how to set up and use jet ventilator.)

Question 10

Post-Operative Management:

You decide to supply jet ventilation through a port in the airway exchange catheter during the procedure.

How would you do this?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 10

As before, I would:

1. obtain the appropriate difficult airway equipment,
2. ensure the presence of a surgeon capable of performing emergent tracheostomy, and
3. have the neck prepped and draped prior to placement of the airway exchange catheter. I would then –
4. ensure adequate sedation and
5. insert the airway exchange catheter,
   
   • being careful not to advance the catheter beyond 26 cm (in adults) or
   • when there was increased resistance, recognizing that this could lead to perforation of the tracheobronchial tree or inadequate expiration (as the catheter is advanced into progressively smaller airways, the space around the catheter is reduced, impeding the expiration of the delivered gas mixture.
   • Assuming the space within the ETT were sufficient for adequate expiration after inserting the catheter (jet ventilation through the exchange catheter should not be employed when the internal diameter of the ETT is < 4 mm following catheter insertion), I would –
6. use an in-line pressure regulator and
7. initiate jet ventilation with 100% Fio2, a pressure of 20-25 psi, and an inspiratory time of less than 1 second. I would then –
8. adjust these settings as clinically indicated to provide adequate oxygenation while avoiding the barotrauma that may occur when the amount of gas entering the lungs exceeds the amount exiting the lungs (i.e. pneumothorax, pneumomediastinum, pneumopericardium, pneumoperitoneum, and subcutaneous emphysema). Finally, I would –
9. remove the damaged endotracheal tube (taking care not to remove the exchange catheter with it),
10. perform careful laryngoscopy (visualization of the oropharynx helps to identify problems with smooth passage of the new ETT over the exchange catheter - i.e. the tip of the ETT catches on the right vocal cord or the arytenoid), and
11. insert the new endotracheal tube over the exchange catheter.

Clinical Notes:

• The complications associated with jet ventilation include – pneumothorax, pneumomediastinum, pneumoperitoneum, pneumopericardium, subcutaneous emphysema, and inadequate gas exchange (i.e. hypoxia and/or hypercapnia). With supraglottic jet ventilation, gastric distention, regurgitation, and gastric rupture would also be a risk.
• With subglottic jet ventilation (as occurs through an airway exchange catheter), the entrainment of room air is limited, (as opposed to supraglottic jet ventilation), allowing for the delivery of higher inspired oxygen concentrations (the entrainment of room air with the injected gas leads to increased tidal volumes and dilution of the oxygen concentration of the injected gas).
• Jet ventilation may not be appropriate for patients with decreased chest wall compliance (i.e. obesity), because this may lead to gastric distention (increased risk of regurgitation; further reductions in pulmonary compliance).
• Jet ventilation is probably not appropriate for patients with an upper airway obstruction (i.e. glottic lesion) that would inhibit adequate exhalation between jet applications (this can lead to progressively increasing airway pressures and barotrauma).
• Jet ventilation may not be appropriate for patients with advanced COPD due to the prolonged expiratory phase associated with this type of pulmonary disease. Moreover, the risk of barotrauma would be significantly increased in the presence of pulmonary bullae.

Question 11

Post-Operative Management:

Four hours post-op the patient has a temperature of 38.9 °C.

Are you concerned?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 11

Recognizing that early post-operative fever is rarely indicative of an infectious process,

his fever is most likely due to a hypothalamus-mediated increase in core and skin temperatures often associated with major burn injury (usually 1-2 °C).

While expected, this fever is concerning because it may represent one component of the hypermetabolic response to thermal injury that includes increased glycogenolysis, gluconeogenesis, severe fat and protein wasting, increased oxygen consumption, and a negative nitrogen balance (the metabolic rate of patients with burns involving > 40-50% of their BSA can more than double).

Unfortunately, this hyper-metabolism may lead to – tissue hypoxia, renal failure, delayed wound healing, and infection.

Question 12

Post-Operative Management:

Four hours post-op the patient has a temperature of 38.9 °C.

What would you do?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 12

I would attempt to attenuate the detrimental effects of this hypermetabolic response by providing:

1. environmental heating, to minimize the metabolic expenditure required to maintain adequate core temperatures;
2. aggressive pain control, to reduce catecholamine release; and
3. adequate nutrition (25 Kcal/kg body weight + 40 calories per % BSA burn injury per 24 hours) via enteral feeding or TPN.

I would, however, keep in mind that this aggressive hyperalimentation requires close monitoring of –

• serum and urinary glucose levels (to avoid hyperglycemia),
• liver function (to identify cholestasis or fatty infiltration), and
• electrolytes.

Question 13

Post-Operative Management:

The nurse calls you to report that the patient has begun to produce dark, cola-colored urine.

What do you think is going on?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 13

Considering this patient’s recent blood transfusion and crush injury from the falling roof beam, this cola-colored urine most likely represents –

• either hemoglobinuria from incompatible blood transfusion, or
• myoglobinuria secondary to skeletal muscle destruction.

The specific diagnosis could be made by –

• serum electrophoresis or
• centrifugation of a blood specimen
  
  • (hemoglobinuria is associated with pink-stained serum, while the serum is unstained with myoglobinuria).

Recognizing that both of these conditions potentially result in acute renal failure, I would –

• administer fluids and mannitol in an attempt to induce diuresis.

If further investigation confirmed rhabdomyolysis, I would also consider –

• alkalinization of the urine with sodium bicarbonate to facilitate the excretion of myoglobin, recognizing that the efficacy of this treatment is controversial.

Question 14

Post-Operative Management:

Later that evening, you are called to evaluate the patient who has become hypotensive and oliguric. Upon evaluating the patient you note a distended abdomen, increased airway pressures, and decreased cardiac output.

What do you think may be going on?

• (A 43-year-old, 6’1”, 96 kg firefighter presents to the trauma suite as a level 1 trauma. He was trapped in a burning building when the roof collapsed, suffering burns to his arms, chest, and abdomen. His fellow firefighters pulled him out of the building after finding him with his left leg pinned under a large beam. He says that when the roof beam fell, it hit him in the torso, knocked him down, and pinned his left leg. He is intubated, has a C-collar in place, and presents for emergency fasciotomy and ORIF of his left femur.*
• PMHx: Hypertension (HTN), Insulin Dependent Diabetes Mellitus (IDDM), Obstructive Sleep Apnea (OSA)*
• Meds: HCTZ, NPH insulin, Lipitor, multivitamin*
• Allergies: NKDA*
• PE: VS: BP = 98/62 mmHg, HR = 120, RR = 22, SaO2 = 98% on 6L oxygen*
• Head/Neck: C-collar in place*
• Lungs: Mild inspiratory stridor*
• Extremities: swollen and tense left thigh*
• Labs: ABG: pH 7.22, PO2 108 mmHg, PCO2 36 mmHg, and SaO2 of 98% on 6 Liters O2*
• Potassium = 5.2 mEq/L*
• Hct = 33%*
• CO Level 20%*
• EKG: Sinus tachycardia*
• CT: Head, Chest, and abdominal CT negative*
• CXR: No acute disease)*

Answer 14

(UBP Live Course – DDx Question – “Finding of … is most consistent with … (primary Dx). However, I’d also consider other possibilities (secondary Dx’s).

—

A recent history of abdominal trauma (roof beam struck his torso) and aggressive fluid resuscitation (for burn injury), combined with a constellation of signs and symptoms that includes – oliguria, hypotension, increased airway pressures, decreased cardiac output, and a distended abdomen, is consistent with –

abdominal compartment syndrome (ACS).

ACS results when trauma, fluid resuscitation, and/or shock-induced inflammatory mediators results in massive edema of intra-abdominal organs, with subsequent cardiac (i.e. decreased CO, decreased venous return, hyper/hypotension, and increased SVR, PAOP, and CVP), pulmonary (i.e. increased dead space, hypercapnia, increased ventilatory pressures), renal (oliguria), gastrointestinal, hepatic, and CNS dysfunction (increased ICP and decreased CPP).

However, I would also consider the possibility that his symptoms are not the result of abnormally high intra-abdominal pressures, but are the result of another life-threatening process, such as –

• tension pneumothorax,
• severe acidosis,
• ARDS,
• pulmonary embolism,
• FES, or
• cardiac tamponade.

To determine whether his clinical condition is the result of ACS, I would measure the intravesical pressure with a Foley catheter to identify intra-abdominal hypertension ( > 20-25 mmHg).

A diagnosis of ACS would necessitate immediate abdominal decompression.