It was the mid-'90s, I was eight years out of residency, and it was before the Haemophilus influenzae vaccine, so meningitis was not uncommon. I was on a busy flu-season shift in the pediatric ED supervising a third-year emergency medicine resident.
He presented the case of a 9-year-old boy who had been transferred to us from another ED for meningitis. A lumbar puncture done four hours earlier that day at the transferring ED was traumatic, and the boy had gotten his first dose of antibiotics before the transfer. He was alert with normal vital signs, but had a severe headache and stiff neck. We decided to repeat the LP for microbiologic diagnosis because it had been only four hours since antibiotic administration. We were swamped, so I went on to the next case while the resident attempted the LP.
The resident returned a short time later, sheepishly reporting that his attempt was also traumatic and that he had only gotten blood. He held up three tubes of bloody CSF.
This was definitely going to take more time than anticipated. I went to talk to the family, and a more detailed history revealed that his headache had started gradually two days before, had gotten progressively worse, and became severe that morning. His neck was definitely stiff, but there were no petechiae, and he had not had a fever at home, at the transferring facility, or at our ED. I considered repeating the LP myself to be sure, but mom wasn't down with that idea. I'd never seen a spontaneous head bleed in a child, but we sent him for a head CT, which showed significant subarachnoid hemorrhage from a previously undiagnosed arteriovenous malformation! Neurosurgery was consulted, and an arteriogram was obtained. He eventually did well.
Resident supervision: There is a balance between giving residents some autonomy so they can learn from mistakes and protecting patients from the consequences of those mistakes. In retrospect, even though this resident was a third-year, I should have done my own history and exam before coming to a plan of action. I likely would have keyed in on the absence of fever, and might have done a CT before another LP attempt. So minus one for not doing my own H&P right away before repeating the LP.
Anchoring: This case was in a busy pediatric ED at a time when meningitis wasn't uncommon. It would have been tempting to accept the transferring diagnosis and admit the child without repeating the LP. I honestly thought we would get a nontraumatic (and hopefully diagnostic) CSF sample, and we would have missed the diagnosis if we hadn't. Sometimes luck steps in where specific intent is absent. So plus one for recognizing this case didn't fit the typical pattern for meningitis and pursuing the repeat LP.