A 38-year-old male suffered two gunshot wounds to the abdomen and was admitted to the ICU after an exploratory laparotomy with small bowel resection, sigmoid colon resection, and one intraabdominal drain placement. Postoperatively, the patient is extubated in the ICU without complications. On postoperative day # 1, he acutely develops decreasing urine output, rising creatinine, and drain output with moderate serous output. The ICU team suspects Acute Kidney Injury. They obtain a fractional excretion of urine sodium, which is between 1% to 2%, and a bedside renal ultrasound demonstrates a normal collecting duct system.
What is the BEST next step?
Correct Answer: B
Early diagnosis of urinary tract obstruction or ureteral injury is important and should be corrected as soon as possible, as delay in diagnosis could lead to kidney injury. All patients with AKI should have a workup for urinary tract obstruction. Ultrasound is the preferred imaging test for this diagnosis. It is important to recognize this patient’s injury and the moderate to high drain serous output with an acute decrease in urine output. This patient had a gunshot wound to the abdomen involving the sigmoid colon, which also should hint the reader to a missed ureteral injury during the abdominal exploration as they are in close proximity. A negative ultrasound has 98% negative predictive value. It is great at ruling out a chronic and acute obstruction. However, it has a false positive rate of 26%. The positive predictive is only 70%. Although this patient’s bedside ultrasound was negative for dilated collecting duct system, you cannot rule out a ureteral injury and must have a high index of suspicion. A urinoma may not be obvious in this case because there is a drain in place draining the serous fluid. If the urinoma does not build up to compress the collecting system, then it is unlikely to see a dilated collecting duct in this acute setting. The next most best step is to send the drain output for creatinine levels and notify the surgical team.
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A 65-year-old patient 12 hours status post renal biopsy presents to the ICU with gross hematuria, acute blood loss anemia, and tachycardia. After two units of packed RBCs and DDAVP, with a normal INR and platelet counts, the patient continues to have significant gross hematuria with continued tachycardia and downtrending hemoglobin with a systolic blood pressure of 90 mm Hg.
What is the next BEST step?
Correct Answer: A
It is important to recognize that bleeding is a primary complication of renal biopsy. Renal biopsy tends to have the highest bleeding risk compared to other biopsy sites with a rate of 1.2%. Bleeding after renal biopsy will most likely occur at three locations. One site of bleeding is into the collecting system, which can lead to microscopic or gross hematuria as seen in the patient above. The other two sites would be beneath the renal capsule presenting with pain post procedure or in the peri-nephric space in the retroperitoneum. The patient above has been given DDAVP and has a normal coagulation panel and a normal platelet count but continues to have gross hematuria with signs of shock. This patient should not be transported to the CT scanner as the patient is currently showing signs of shock. Although the CT angiography of the abdomen would be an ideal study to evaluate for active extravasation, this patient has gross hematuria with continued bleeding. Monitoring the patient and continuing transfusion is reasonable after the surgical service has evaluated the patient. In bleeding patients, it is reasonable to allow “permissive hypotension.” It is better to gently resuscitate than start vasopressors in a bleeding patient. The sudden rise in the mean arterial pressure and systolic blood pressures could lead to increased bleeding or reactivation of bleeding. The best decision for this patient is to get a surgical consultation and have interventional radiology on standby for angiogram, which can be both diagnostic and therapeutic in this patient while the patient is being monitored closely and transfused with appropriate transfusion ratios.
A 25-year-old male was involved in a motor vehicle crash in which he was clearly intoxicated. On presentation to the emergency department he is tachycardic and hypotensive and has suffered bilateral superior and inferior pubic rami fractures, with resulting acute blood loss anemia. He is transfused two units of packed RBCs. On presentation to the ICU, his blood pressure remains 100/70 mm Hg. On complete evaluation of the patient, you notice a small amount of blood at the penile meatus and no foley had been placed in the ED.
What is the NEXT appropriate management of this patient?
Correct Answer: D
Bladder injury occurs in approximately 3.4% of patients with pelvic trauma, whereas urethral injury occurs in only 1% of these patients. Males are 10 times more likely to have a urethral injury in such situations. If the physical examination reveals any signs of genital bruising, blood at meatus, high riding prostate, and gross hematuria, urethral injury should be suspected and ruled out. Advance Trauma Life Support recommends ruling out a urethral injury before inserting a Foley to avoid further injury, although the data on this are sparse. A systematic review of a thousand pediatric patients revealed the total incidence of genitourinary injury to be approximately 11% to 12%. Of these patients, 26.4% had urethral injury. As the severity of the pelvic injury worsened, the percentages appropriately increased. It is important to recognize this and have a high suspicion of injury during the examination of such patients. The first two choices involve placing a Foley catheter before any investigative work. CT Cystogram is ideal to rule out bladder injury. Retrograde Urethrogram is the test of choice to rule out urethral injury.
All the medications below can lead to acute urinary retention EXCEPT:
Pharmacologic agents associated with urinary retention:
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