Lions and Tigers and Bears
Dr. Loice Swisher’s daughter had five episodes of unexplained vomiting without a fever in just one month during 1999. Thinking through the files in her mind, she was unable to shake the memory of a young child with the same complaint 12 years before. The well-looking child had been bounced out of the ED four times with "viral syndrome" and "gastroenteritis." The diagnosis was a posterior fossa tumor.
“How did this happen?” she asked. The attending shrugged, offering up various possibilities. It was a difficult diagnosis because the symptoms at first are nonspecific. It is uncommon. The prior docs probably didn't get her up to walk or look in her eyes. They probably didn't think of it. He concluded, "To an ER doc, unexplained vomiting is a brain tumor until proven otherwise."
That single phrase altered the course of her life. A "reassurance MRI" showed a 5 cm brain cancer, a medulloblastoma. Her daughter navigated a course of radiation, chemotherapy, and multiple complications, and Dr. Swisher started an entirely new medical education in the art of diagnosis.
Amal Mattu, MD, reminds those of us in emergency medicine to be on the lookout for lions and tigers and bears, not horses and zebras, Dr. Swisher explained. As an emergency physician and mother, she knows the profound impact this approach has on a patient's life. Using real cases, this blog aims to expose the lions and tigers and bears out there ready to bite.
Saturday, July 2, 2016
"What do you think about this VBG from last night?" I asked, thrusting a ribbon of paper at my colleague.
pCO2 47 mm Hg
pO2 59 mm Hg
Na+ 149 mmol/L
K+ 4.2 mmol/L
Cl- 99 mmol/L
Ca++ 1.27 mmol/L
Glu 211 mg/dL
Lac >20.0 mmol/L
tHb 16.3 g/dL
"Was he dead?" he queried.
"What was his anion gap?" came the next question.
"Ethylene glycol? Did you intubate him?" he asked.
That was a great guess, but it was actually PCP and cocaine. The patient, out of control, was TASERed a few times. By the time he got to the ED, though, he was unresponsive, breathing like a freight train, and sweating so much he soaked the sheets. I didn't want to intubate him because he was doing a much better job blowing off his hydrogen ions than I ever could.
I certainly didn't want to make that acidosis any worse. I was surprised his heart could keep beating in the environment he already had. I went with benzos, several liters of fluids, and followed the end-tidal CO2 (which was only 16 on arrival). The gap was down to 21 within 90 minutes with a much improved VBG.
VBG 90 Minutes Later
pCO2 39 mm Hg
pO2 38 mm Hg
Na+ 140 mmol/L
K+ 5.3 mmol/L
Cl- 112 mmol/L
Ca++ 0.95 mmol/L
Glu 94 mg/dL
Lac 8.2 mmol/L
tHb 13.4 g/dL
These previously combative but now "not fighting" patients are the ones that make me worry that they are on the edge of the cliff, potentially crashing at any moment. Perhaps that is because this isn't the first (or second or third) patient I have seen with a pH less than 6.8 from a drug-induced agitated state. Maybe the quiet ones should cause even more angst.
My guy went to the CCU, and his normal CPK was above 10,000 within 12 hours. He did require sedation until the PCP and cocaine wore off. The young human body is remarkably resilient; he was back to his regular life just a few days later.
Take-Home Point: Beware of the unresponsive, previously seriously agitated patient; he may be close to death.
Thursday, June 2, 2016
A young woman came in after a FOOSH injury complaining of difficulty moving a painful shoulder. The Y view was difficult to obtain, but the AP view is below. What three radiographic signs help make the diagnosis?
The signs include:
n The light bulb sign is when the humeral head is rotated internally so it looks more like a lightbulb than a club.
n The rim sign where there is an increased distance (more than 6 mm) between the arc of the glenoid and the arc of the humeral head. The distance is much closer at the top of the glenoid than the bottom in this image.
n There is an angle in Moloney's arch. There should be a smooth scapulohumeral arch. Peaks in the glenohumeral location should raise suspicion of a posterior shoulder dislocation. The equivalent of Moloney's arch in the hip is Shenton line.
This is a posterior dislocation. These account for only two to four percent of shoulder dislocations, and they can look remarkably normal in general location, which means as many as 50 percent have been reported to be missed on initial radiographs. A good Y view can be exceedingly helpful in making the diagnosis.
Request an axillary view or a CT if a Y view is difficult. Bedside ultrasound is likely the quickest way to confirm the diagnosis for those skilled at musculoskeletal point-of-care scanning.
A diagnostic Y view was eventually obtained. The shoulder was put back using a traction-counter traction technique under conscious sedation.
Tips to Remember:
n Careful inspection of the AP shoulder film can increase suspicion for a posterior shoulder dislocation.
n Other imaging modalities are available to confirm the diagnosis.
Monday, May 2, 2016
"I'm going to get a facial CT on this guy because his eye won't open," the resident said to me as he came out of the patient's room.
Suddenly aware that a lateral canthotomy might be in our immediate future, I asked, "What do you mean? You can't get his eye open? What happened?"
Changing directions, I entered the room to find a surprisingly cooperative patient with a grossly deformed face. The peri-orbital contusion prevented him from voluntarily opening his eye. So is that pre-septal or retro-orbital? We needed to take a look.
Touching the upper lid, the immediate sensation of bubble pop burst forth under my gently retracting fingers. No proptosis or lateral canthotomy now. His vision was normal with no hyphema in the anterior chamber. The extraocular muscle was intact with no entrapment. A lateral subconjuctival hemorrhage likely meant a zygomaticomaxillary complex fracture.
Yep, the red flags of extensive subcutaneous emphysema and a lateral subconjunctival hemorrhage were on the mark. He had a zygomaticomaxillary complex (ZMC) fracture. The arch bar artifact confirmed that our patient was not a novice to trauma.
By whatever name you know ZMC fractures (tripod, tetrapod, malar, or trimalar), these have been thought to be the second most common facial fracture, second only to nasal fractures. These fractures include the zygomatic arch, the inferior and lateral orbital rim, and the anterior walls of the anterior and posterior sinus. Displaced fractures can cause infraorbital numbness and difficulties chewing.
This patient had impressive swelling and multiple fractures, but was discharged on antibiotics and pain medication with the ENT's blessing.
Tip to Remember: When there is a traumatic lateral subconjunctival hemorrhage, include a zygomaticomaxillary complex fracture on the differential.
Friday, April 1, 2016
A man hobbled into the emergency department complaining of continued ankle pain and increased swelling after falling from a ladder the day before. Ankle images were ordered. The mortis, syndesmosis, and malleoli appeared normal, but the massive medial soft tissue motivated a continued search. Was there something wrong with the lateral talus?
The subsequent CT scan delineated a comminuted fracture of the talar lateral process extending to the subtalar joint — a snowboarder's fracture.
Fractures of the lateral process of the talus are relatively uncommon, frequently missed, and can end up with long-term disability. It has been reported that 15 percent of ankle fractures are related to the lateral process, and missed diagnosis has been initially reported in 40-50 percent of cases. The mechanism of injury is inversion and dorsiflexion, causing the lateral process to be compressed between the distal fibula and the calcaneus. Snowboarders incur this injury approximately 15 times more frequently, and falls and motor vehicle crashes are also implicated in lateral talar process fractures.
Tips to Remember
< Maintain a high index of suspicion for a fracture of the lateral process of the talus with ankle sprains.
< Consider a CT scan for better visualization of this region if there is concern.
< Caution patients with suspected ankle sprains to seek re-evaluation if not improving as expected in the next one to two weeks.
"Imaging of Fractures of the Lateral Process of the The Talus, A Frequently Missed Diagnosis," Eur J Radiol 2003;47(1):64; http://bit.ly/1oMFgg4.
"Fractures of the Lateral Process of the Talus: Snowboarder's Fracture," Podiatry Institute, 2008; http://bit.ly/1oMFgg4.
Tuesday, March 1, 2016
It's 2 a.m. I glance up from my computer screen where I have been diligently clicking boxes on the EMR to see a 20-something man hobble down the hallway following the nurse to a hallway bed. His left foot had a normal heel strike, but the right always came down on the ball of the foot. Curiosity piqued, I opened a new tab to consider this patient's problem.
The 28-year-old jumped over a fence to get away from a dog, landing on his right heel. He said he had not been able to put pressure on the back of his foot since the injury occurred an hour earlier. It was a pleasure to have something so straightforward.
I checked for an intact Achilles' while I watched for plantar flexion with a squeeze of the calf muscles, and then evaluated for tenderness or defects by directly palpating the tendon. Then I cupped my hand around the heel squeezing in all directions. The directive "don't do that again" virtually confirmed my suspicion that this young man suffered from a calcaneal fracture. I told him as much as I placed the x-ray order.
Seeing the patient wheeled back to his bed, I popped up the images on PACS.
What? It looked pretty normal. Where was that fracture that had to be there? There was a small sclerotic line across the tubercle, but that wasn't enough for me make the call. Sure, I could just treat him like a fracture and hope that he followed up. Still, I really wanted to know. Thinking about the options, I came up with three:
n Send to our out-of-house radiologist for a read, which would incur an expense to the hospital.
n Get a CT scan.
n Send him back for axial calcaneal views.
By choosing the last option, I had no doubt left within minutes.
Tips to Remember:
n Approximately one-third of calcaneal fractures are extra-articular, and thus Böhler's angle and the Critical Angle will be normal.
n If the patient will not walk on the heel and has pain with a compressive grip cupping the heel (medially and laterally), highly consider the possibility of calcaneal fractures.
n Special axial images give additional views of the calcaneal tubercle and potentially the sustentaculum tali.