Since 1996, the premise that most febrile seizures carry a benign prognosis has not been challenged. In fact, several additional reports have further supported the AAP Practice Parameters urging a conservative neurodiagnostic approach.8–10
At the time the guidelines were published, a cohort, comprised exclusively of well-appearing children with first-time simple febrile seizures, was subjected to an LP 30% of the time—a rate that has been described as distressingly high.11
These children were also admitted or transferred to another facility 14% of the time (a pattern also difficult to justify). Those findings suggested that adherence to the guidelines required a change in common practice (ie, the guidelines were not simply an affirmation of the prevailing standard of care). Interestingly, head CTs were performed relatively infrequently at that time (5.1%).
With respect to the performance of LPs, our current study presents encouraging results regarding adherence to the guidelines. For all patients in the cohort, the LP rate was only 5.2%. Even when patients with recurrent febrile seizures (and children with abnormal neurological examinations) are excluded from the analysis, the rate rises insignificantly to 5.3%. There is also evidence that this low LP rate stems from practitioners closely following the AAP’s specific suggestions regarding the relationship between the patient’s age and the need for LP (the guidelines do suggest that LP be “considered” for patients <18 months old).5
In our earlier cohort, 19% of children older than 18 months underwent LP. In our current study, a mere 3.3% of such patients received an LP.
Although the overall rate of admission or transfer (12%) for our entire study population seems high, the rate in a matched subset of well-appearing first-time febrile seizures (7.6%) represents a significant decline from our previous study (14%). This decline is even more impressive when one considers that roughly a quarter of our earlier cohort had been seen in children’s hospitals’ EDs, where the admission rate was low (4%), and no transfers were recorded. If children’s hospitals are excluded from our previous analysis, 18% of children had been admitted or transferred, suggesting that the current rate of 7.6% actually represents a 58% decline in admissions in the community hospital setting.
These results may imply closer adherence to guidelines, but the decision to admit or transfer a child after a febrile seizure is less algorithmic than other elements of the evaluation. Factors such as parental anxiety, lack of primary care, or extended support and follow-up may all play a role.12
We are also unable to account for other temporal trends in pediatric ED admissions in general. In addition, it is possible that having performed a head CT more frequently, practitioners felt more confident discharging patients home (although this effect cannot explain the entire difference observed).
The relatively high rate of head CTs (11%) is a bit puzzling. Inasmuch as a CT is of little value in ruling out meningitis, it is unlikely that physicians simply “compensated” for the low LP rate by performing more CTs. Nor does it appear that the use of CT was entirely routine or indiscriminate: children without a fever in the ED or without a previous history of seizure were most likely to undergo CT. However, removing these patients from the analysis still leaves a rate of 9.6%.
One possible explanation is that access to a CT scanner has now become a standard of care for nearly all general EDs. The ubiquity of these scanners may also have reached the public consciousness, causing parents to put additional pressure on ED providers. Although the fixed costs of purchasing and maintaining a scanner are still relatively high, the variable costs associated with performing a single scan are low. Therefore, ED practitioners may have viewed this as a quick, easily obtainable, noninvasive, low-cost, low-risk test. We would caution, however, that the performance of this procedure in children, especially when sedation and/or restraints are used, may introduce a higher risk than that associated with adults.13,14
As implied earlier, it is widely accepted that the occurrence of a febrile seizure adds no independent risk for serious bacterial illness.9
However, by definition, all children with febrile seizures have fever. The search for an etiology of the fever should be guided by known risk factors for serious bacterial illness, such as age, sex, height of fever, and general appearance.15
Therefore, it is not surprising that our current cohort differs little from our previous one in the evaluation of patients for bacteremia and urinary tract infection.
This study has all the limitations inherent in any retrospective cohort design.16
In addition, the 42 community hospitals whose records were available for review were not randomly selected. They do represent a wide range of geographic and clinical environments throughout the United States. However, all the physician groups represented were contracted with the same billing company. Thus, quality assurance and monitoring procedures integral to this arrangement may limit the generalizability of our results to other groups of ED practitioners.
This limitation is even more relevant to our attempt to make inferences about changes in utilization rates over time. Our referent cohort consisted of patients seen in the Chicago metropolitan area. Although both cohorts were well matched with respect to clinical factors such as age and height of fever, it is conceivable that the differences we noted are not due to temporal trends, but rather geographic variation.17
However, geographic variation in the management of febrile seizure has never been described, and there is little a priori reason to suppose that it exists. In addition, the previous sample of 7 hospitals included both urban and suburban centers. More importantly, the earlier cohort included 125 visits to tertiary children’s hospitals. The lower utilization rates seen in those hospitals would bias comparisons toward the null.
Obviously, data missing from the reviewed records can cause us to underestimate utilization rates. However, all the participating physician groups used proprietary template-based documentation that has been shown to improve information capture.18,19
In addition, our main outcomes of interest, including admissions, LPs, and head CTs, are fairly significant expenditures and were unlikely to be missed.
A fairly large number of hospitals were included in this study. However, for infrequent management decisions, it is possible that a relatively small number of “outlier” groups skewed our data. If there were a few EDs at which LPs and/or head CTs were routinely performed, this might cause us to overestimate utilization rates. Again, this would bias our comparisons with our previous cohort toward the null. In any case, given what is known about ED practice variation, the nonuniform distribution of various management decisions across physician groups is expected.6,20–23
Our fairly large sample of more than 40 EDs helps minimize this effect.
In relative terms, we have implied that the use of head CT is inappropriately high. However, it is still fair to question the clinical importance of this rate. Eighty-nine percent of the patients in our study did not
undergo head CT. Future study would be useful to determine whether this increase compared with the historical cohort represents a steady trend that can lead to truly harmful rates of radiation exposure and unjustifiable costs. In fact, there is a growing body of evidence suggesting that head CT is also unnecessary for first-time afebrile seizure.24
If this information is incorporated into practice in the same way our data suggest that the literature regarding LPs for febrile seizures has been, we would expect head CT rates for all types of pediatric seizures to soon decline.
Our results provide evidence that the evaluation of children with febrile seizure by ED physicians in community hospital settings is consistent with the minimally invasive approach suggested by the AAP guidelines. In particular, LP rates that had previously been recorded to be higher than 30% were only 5%. Rates of hospitalization were also relatively low. Investigations for bacteremia and urinary tract infections are not addressed by the guidelines, and rates were consistent with previous studies. Although overall usage rates remain low, the use of head CT for these patients seems to have increased. Further study is indicated to determine whether this finding represents a trend that will be sustained in the future.