Background: Emergency medicine (EM) residents have a procedural requirement (PR) for 15 lumbar punctures (LPs) during residency. We previously showed that in seven emergency departments (EDs) the annual number of LPs decreased 70% from 2004 to 2016. This may be due to two recent developments: computed tomography scans now more reliably detect small subarachnoid hemorrhages and new vaccines have been introduced, reducing ED bacterial meningitis visits. The number of LPs available in many EM residencies may be insufficient for PR completion. However, we did not take into account the possibility that more LPs may be done in hospitals with an EM residency than in hospitals without a residency. Our goal was to determine if the number of LPs would be sufficient to fulfill the PR using data only from a hospital with an EM residency.
Methods: Design: Retrospective cohort of ED visits. Setting: One New Jersey suburban ED with an EM residency. Population: Consecutive patients seen by ED physicians from 1/1/2004 to 8/31/2016. Protocol: We identified patients having an LP using Current Procedural Terminology codes. Data Analysis. For 2016, we corrected for the fact that data were collected during only the first 8 months of the year. We calculated the percentage of ED patients who had an LP. We used percentage rather than total number of LPs as ED visits increased by 35% from 2004 to 2016. Most of this increase was due to closures of other hospitals in the area.
Results: Of the 982,773 total patients, 2326 had LPs (0.24%). Median age was 19 years (interquartile range, 0.24 to 43). Females comprised 52%. In 2004 and 2016, the corrected annual volumes were 67,602 and 91,307, the corrected numbers of LPs were 247 and 96 and the percentages of patients with LPs were 0.37% and 0.11%, respectively. This is a 70% decrease in LPs, similar to what we found previously.
Conclusion: Each resident needs 15 LPs (average = 5 per year) to graduate, of which only 30% may be simulated. The smallest 3-year ED residency program with 18 residents would need at least 70% x 18 x 5 = 63 LPs annually. The minimal ED volume to fulfill the PR would be 57,000 since 0.11% x 57,000 = 63. In most EM residencies, the number of LPs is likely to be sufficient for the residency procedural requirement despite a marked decrease in LPs in recent years.