Your shift is just beginning when you are notified that EMS is bringing in a 20-year-old male patient who was struck by a motor vehicle. As your team assembles, you notify the CT scanner and ask him to keep it open and available. When the patient arrives, you find that he has decorticate posturing, a large scalp hematoma, and multiple facial fractures. After you intubate him via RSI and complete your initial assessment, he is quickly wheeled over to CT. His head CT shows a large epidural hematoma with 10 mm of midline shift. His abdominal CT reveals a splenic laceration with active extravasation. You begin your interventions to manage the patient’s elevated intracranial pressure and arrange transport to the nearest Level 1 trauma center. As you hear the helicopter landing, you notice that the patient’s pupils have become asymmetric. You ask yourself, “Which would be better to control the patient’s intracranial hypertension: mannitol or hypertonic saline?”
A short time later, EMS wheels a first-time marathon runner into the critical care bay. She was witnessed to have collapsed at mile 22 with seizure-like activity of 1 minute duration. She is currently postictal with a normal fingerstick blood glucose. Her vital signs are as follows: heart rate of 118 beats per minute, respiratory rate of 24 breaths per minute, blood pressure of 138/90 mm Hg, rectal temperature of 38.3°C, and oxygen saturation of 98% on a nonrebreather mask. You wonder if she might have suffered a heat stroke. Her temperature is elevated — but not enough to cause a seizure. Besides her continued altered mental status, she has an otherwise normal exam. You send her off to the CT scanner to look for acute intracranial pathology. As her scan is completed and the results are confirmed by the radiologist as unremarkable, the lab calls back with a critical value: her serum sodium is 109 mEq/L. The nurse calls out to you from the scanner, “Doc, she’s seizing again!”
You were worried about the motor vehicle accident patient’s worsening mental status and signs of herniation. Based on the available evidence indicating that HTS with dextran is as effective as mannitol to reduce ICP (and the fact that it may help support this patient’s systemic pressure and CPP during helicopter transport if his splenic laceration continues to bleed), you decided to infuse 250 mL of 7.5% HTS with dextran. Fortunately, his neurologic status did not deteriorate any further, and he was quickly transferred to the nearest Level 1 trauma center, where he underwent acute decompression for his epidural hematoma and angiography embolization for his splenic laceration.
Based on your second patient’s history and sodium level, you quickly determined that she had suffered exercise-associated hyponatremia. It was acute in onset, and, because of her seizures, you determined that she most likely had cerebral edema. After intubation, you administered 100 mL of 3% HTS. She had no continued seizures and was transferred to the ICU. Her repeat serum sodium 1 hour later had increased by 4 mEq/L. After a short stay in the ICU, she was discharged home with a normal neurologic status.
Jeffrey A. Holmes, MD
February 4, 2013