Your previously described 47-year-old burn patient is in the midst of being appropriately resuscitated based on your Parkland formula. The patient’s hourly urine output is measured to be about 1 mL/kg. During the last couple of hours of your initial 24-hour postinjury resuscitation, you note that the patient’s urine output starts to decrease. In addition, you note that the patient is having difficulty breathing with frequent episodes of desaturation despite being on a nonrebreather. Your physical examination reveals a distended abdomen with increased abdominal girth. The patient is intubated, and you note elevated peak airway pressures at 45 mm Hg. You ask the nurse to perform a bladder pressure, which is noted to be 25 mm Hg.
What is your diagnosis, and what is the appropriate treatment?
Correct Answer: D
A clinician who is guiding the management of a burn patient must be privy to the complications of aggressive fluid resuscitation. Peripheral edema, pulmonary edema/effusions, and abdominal hypertension with subsequent abdominal compartment syndrome are a few of the problems that may arise despite what would be considered adequate fluid resuscitation.
Burn patients, in addition to any other patient requiring aggressive fluid resuscitation, are susceptible to secondary abdominal compartment syndrome (ACS). Patients who present with ACS will have preceding intraabdominal hypertension (IAH), which is defined as an intra-abdominal pressure (IAP) greater than 12 mm Hg that is measured at least three times, 4 to 6 hours apart. When the IAP is greater than or equal to 20 mm Hg and there is at least failure of one organ system not previously failing, the diagnosis of ACS is confirmed.
The treatment of abdominal compartment syndrome is a formal laparotomy. The treatment of secondary ACS in a burn patient is not escharotomy, as the issue is from intra-abdominal fluid causing increased intra-abdominal pressure.
References:
A 24-year-old male is admitted to the ICU after suffering 54% deep partial- and full-thickness burns to his face, torso, and arms after being involved in a house fire. At 72 hours post burn, his heart rate and cardiac output remain significantly elevated.
Which of the following would best treat this patient’s tachycardia and prevent subsequent cardiac stress and myocardial dysfunction?
Correct Answer: A
The patient in this question has a large body-surface-area burn and is exhibiting signs of sustained sympathetic surge. Such patients develop marked tachycardia, 150% higher than predicted, and may remain elevated for up to 2 years after the burn. Likewise, cardiac output has been shown to be 150% higher than predicted for healthy adults and remains high at time of discharge. Increased cardiac stress and myocardial dysfunction may be main contributors to mortality in large burns, implying the therapeutic need to improve cardiac stress and function.
To reduce the risk of cardiac failure, judicious fluid resuscitation should be performed upon a patient’s arrival to the hospital. For the cardiac dysfunction or hyperdynamic state that occurs in almost all patients with burns >40% TBSA, nonselective ß-blockade is recommended. Propranolol, a nonselective ß-receptor antagonist, used at a dose titrated to reduce the heart rate by 15% to 20%, has been found to diminish cardiac work in the burn population.
A 66-year-old male sustains a 25% second-degree scald burn when a large pot of boiling water is spilled onto his torso and lower extremities. He is immediately transferred to a burn center. During his course of treatment, he is started on 5 mg oxandrolone PO BID.
Which of the following physiologic changes has been associated with the administration of this drug?
The hypermetabolic response to burn injury is associated with increased substrate turnover, cachexia, and poor clinical outcomes. Therefore, management of hypermetabolism remains a clinical priority. Treatment with oxandrolone, a testosterone analogue with a low level of virilizing androgenic effect, improves muscle protein catabolism, reduces weight loss, and increases donor-site wound healing. For adults with moderate to severe burns, 10 mg PO BID is recommended. In older patients >65 years of age, the recommended dose is 5 mg PO BID.
Oxandrolone, a synthetic analogue, administered orally, offers only 5% of the masculinizing effects of testosterone and is safe for both genders. Oxandrolone, when administered at a dose of 0.1 mg/kg twice daily, improved net muscle protein synthesis and protein metabolism in severely burned patients.
During the acute phase post burn and up to 1 year of treatment, oxandrolone increased lean body mass, bone mineral content, and muscle strength. In addition, it decreased length of stay by decreasing time between operations for patients randomized to receive oxandrolone plus standard of care. Oxandrolone results in considerable improvements in lean body mass, protein synthesis, and overall growth in burn patients, mitigating the 1% risk of hirsutism and hepatic dysfunction that can be seen with treatment.
It must be noted that although anabolic steroids can increase lean body mass, exercise is essential to developing strength.
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