A 34-year-old woman is in the Intensive Care Unit after she jumped out of the third-story window of a burning building. The patient sustained multiple bony fractures and approximately 50% total body surface area burns. The patient is intubated, sedated, and mechanically ventilated. For the first 24 hours after admission, she received aggressive fluid resuscitation that maintained her urine output at an appropriate 0.5 mL/kg/hour. However, over the past couple hours, the patient's urine output has progressively decreased despite additional fluid boluses being given, and she has been difficult to ventilate. In the last hour, urine output was 8 mL. Temperature is 37.2 C (99 F), blood pressure is 132/88 mm Hg, and pulse is 128/min. Peak inspiratory pressure is persistently high at 36 cm H₂O (normal:

Question

A 34-year-old woman is in the Intensive Care Unit after she jumped out of the third-story window of a burning building. The patient sustained multiple bony fractures and approximately 50% total body surface area burns. The patient is intubated, sedated, and mechanically ventilated. For the first 24 hours after admission, she received aggressive fluid resuscitation that maintained her urine output at an appropriate 0.5 mL/kg/hour. However, over the past couple hours, the patient's urine output has progressively decreased despite additional fluid boluses being given, and she has been difficult to ventilate. In the last hour, urine output was 8 mL. Temperature is 37.2 C (99 F), blood pressure is 132/88 mm Hg, and pulse is 128/min. Peak inspiratory pressure is persistently high at 36 cm H₂O (normal: <20-25). On examination, burn dressings are present on all 4 of the patient's extremities and around the patient's abdomen and lower back. Heart and lung sounds are normal. The abdomen is distended and tense to palpation. A urinary catheter is present, with scant yellow urine in the container. Chest x-ray reveals normal endotracheal tube position and no infiltrates. Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d8e9_cb32_bc81_4d211368f2df_MD0003_00 This patient who received aggressive fluid resuscitation for trauma and severe burns now has a tensely distended abdomen and evidence of intraabdominal organ dysfunction (ie, renal dysfunction with decreasing urine output). This presentation is most concerning for abdominal compartment syndrome (ACS) and should prompt measurement of bladder pressure, which estimates intraabdominal pressure (IAP). Patients receiving massive fluid resuscitation are at increased risk for ACS, especially when coupled with conditions (eg, trauma, burns) that cause a systemic inflammatory response, increased capillary permeability, and third spacing of fluids (including into the abdominal cavity). The resulting increase in IAP may decrease perfusion to intraabdominal organs (ie, abdominal perfusion pressure = mean arterial pressure - IAP), resulting in organ dysfunction. Increased IAP also causes diaphragmatic elevation and extrinsic compression of the lung, leading to high pressures during ventilation (eg, peak inspiratory pressures). Measurement of bladder pressure, via a foley catheter attached to a pressure transducer, is the standard method to estimate IAP. If ACS is present (eg, IAP >25 mm Hg), surgical decompression of the abdomen (ie, laparotomy without fascial closure, allowing for an open abdomen) may be necessary. (Choice A) Bilateral chest tubes may be indicated to treat pleural collections of air or fluid, which can compress the lung and increase inspiratory pressures. However, they are not indicated in this patient with a normal lung examination and chest x-ray. This patient's difficulty with ventilation is likely due to extrinsic lung compression from increased IAP and diaphragmatic elevation. (Choice B) Intravenous mannitol, an osmotic diuretic agent, is sometimes used in the management of increased intracranial pressure to decrease cerebral edema. However, diuretics are not typically used in management of ACS and may cause intravascular volume depletion that further decreases intraabdominal organ perfusion. (Choices D and E) A 3-story fall may cause blunt chest trauma and blunt cardiac injury, with the potential for myocardial dysfunction (which transesophageal echocardiography can evaluate) or cardiac tamponade (which may require pericardiocentesis). Myocardial dysfunction and cardiac tamponade can both cause cardiogenic shock, impaired renal perfusion, and decreased urine output; however, they are unlikely given this patient's normal blood pressure, lack of pulmonary edema, and normal heart sounds (vs new murmur or distant heart sounds). Educational objective: Decreased urine output and high peak inspiratory pressures in the setting of a tensely distended abdomen are concerning for abdominal compartment syndrome (ie, intraabdominal hypertension causing organ dysfunction). Bladder pressure measurement can estimate intraabdominal pressure. References: Abdominal compartment syndrome as a multidisciplinary challenge. A literature review. (http://www.ncbi.nlm.nih.gov/pubmed/30574563)

A 34-Year-Old Woman Is in the Intensive Care Unit After