The data generated by the Healthcare Cost and Utilization Project provide a unique opportunity to examine the delivery of burn care on a national level. In this study, we found that almost half of all burned patients were treated at facilities that are not only non-verified burn centers but are not even self-designated burn care facilities. It appears that burn extent and location remain primary determinants of burn treatment location.
Overall, age was an important determinant of treatment location with younger patients being more likely to be treated at verified and non-verified burn hospitals, especially those younger than 5 years of age. At the other extreme, older adults were more likely to be treated at non-burn facilities. This finding is consistent with the trauma literature, where MacKenzie demonstrated that those treated in non-trauma centers tended to be older and female, with multiple co-morbidities (unadjusted data).(10
) Although more likely to be treated at non-burn hospitals, the median burn size for elderly patients was smaller than those presenting at verified and non-verified burn facilities. Further, verified burn centers treated twice as many elderly patients with burns >40% TBSA than those at non-burn hospitals.
One speculative reason for non-burn center treatment of the elderly may be the desire to remain closer to home rather than travelling sometimes hundreds of miles to a burn center. A less intuitive reason may be the greater number of comorbidities in this population. In general, patients with fewer comorbid conditions were less likely to be treated at a verified or non-verified burn hospital. Data from the national burn repository suggest that mortality dramatically increases in the older population, two-fold among 65-74 year olds and five-fold in those older than 75.(11
) In addition, there may be social pressures why elderly patients are not transported to burn centers. If a patient had been treated for decades by a family physician familiar with their medical history, there may be a reluctance to transfer the patient to a verified or non-verified burn hospital. With less experience managing large burn injury, there may also be a tendency to accept clinical nihilism. That is, the assumption that an injury or burn in the elderly patient will result in a poor outcome and that the initiation of aggressive burn care may still ultimately lead to a poor outcome. Such attitudes toward early prognosis after severe injury have been well documented in the neurosurgical literature.(12
) The potential danger in such a nihilistic approach is that it will certainly lead to a self-fulfilling outcome. Treatment location and outcomes in this segment of society will become increasingly prominent with our aging population.
We examined the extent to which treatment at a burn center was consistent with the triage and referral guidelines established by the ABA. Patients with evidence of inhalation injury and burns to the head and neck were more likely to be treated at verified or non-verified burn centers. Further, patients who sustained electrical injury were more likely to be treated at a verified center. These findings are consistent with previous studies examining factors associated with burn center treatment.(2
) Interestingly, patients with >40% TBSA burns were treated at non-burn hospitals—this was particularly true for patients with multiple co-morbidities. With an inter-disciplinary focus as a component of burn center designation, it would be expected that medically complex burn patients should be treated at such centers. In fact, several studies have demonstrated that patients who receive optimal burn care at verified centers may have a better functional outcome after discharge.(5
) This may provide an opportunity for the burn community to educate and reinforce transfer criteria to non-burn hospitals, as well as for CMS to consider whether payment for treatment of large burns outside of burns centers is appropriate.
Neither inhalation injury nor %TBSA was an independent predictor of treatment at a verified burn center. However, when inhalation injury was present, %TBSA was highly predictive of treatment at both non-verified and verified burn centers. This may be due to the high correlation between burn severity and the likelihood of having an inhalation injury. However, this effect modification may represent an unmeasured relationship between burn severity and treatment location.
Regional variability of burn care was heterogeneous with the exception of Western states. Although 90% of the population studied lived in a state with a verified burn center, fewer than half were treated at one. Although many patients were treated in non-burn hospitals, states with verified burn centers were less likely to treat burned patients at non-burn hospitals or non-verified burn centers.
Payer status varied by hospital type, with a significantly lower proportion of Medicare patients treated at verified burn centers. This is correlated with older, co-morbid patients treated at non-burn hospitals. As previously stated, it is difficult to determine whether payer status, age, co-morbidity, or a combination of these was the major factor that determined burn treatment location. Half of all patients with commercial insurance were treated in a non-burn hospital, with an equal distribution between non-verified and verified burn centers. Patients with worker's compensation were almost twice as likely to be treated at a verified burn hospital, where non-verified centers were slightly more likely to treat those with Medicaid. Payer status appeared to be an independent predictor of treatment location, even after accounting for age, burn size, and the presence of an inhalation injury. This finding differs from the trauma literature where uninsured patients were twice as likely to be treated at a trauma center.(4
) Burn hospitals were more likely to treat those with commercial or workers compensation insurance.
There are several limitations to this study. First, the Healthcare Cost and Utilization Project is not designed specifically to collect detailed information on burn patients. As an administrative database, it is likely that estimation of burn size may be misclassified as either over- or underestimated. Collis et. al. described significant underestimation of burns larger than 20% TBSA and overestimation of smaller burns.(16
) More commonly, there is overestimation in burn size, especially among non-specialists who may assess few burned patients per year. We have demonstrated that referring physicians can incorrectly estimate burn size up to 3-fold greater than true burn size.(14
) Such misclassification of burn size, especially among non-burn hospitals, may have overestimated the severely burned population. Further, the outcome measures captured in a database not designed for that purpose are crude and may not reflect a useful measure of quality among facility types. For these reasons, we did not address outcome measures in this study.
Quality control in analyses of large datasets is an important consideration. The HCUP-SID used in our study generates its data from UB-92 billing forms. Although purely administrative in nature, it remains one of the most comprehensive datasets because it represents over 90% of all U.S. hospitals. HCUP quality control is the internal responsibility of each participating hospital. Although burn-specific databases such as the National Burn Repository exist, it is only comprised of patients admitted to participating burn centers. As we have demonstrated, this represents a fraction of all U.S. burn patients. Both the HCUP and NBR are patient de-identified, therefore a direct comparison of data quality would not be possible. Furthermore, burn center verification status cannot be ascertained in the NBR.
In the current economic climate, private and government agencies are becoming more interested in defining therapies, systems, and proven guidelines that improve patient outcome. The trauma verification process has been shown to improve patient mortality, length of stay, and overall care of the severely injured patient.(17
) Such convincing data is less prevalent in the burn literature. Palmieri et. al. attempted to examine outcomes between burn centers that were verified and non-verified in California.(19
) They found that verified centers had longer lengths of stay without a mortality difference. Our study is one of the first to not only examine the characteristics of treatment location among burn hospitals, but compares multiple states. Future exploration of national treatment and outcome measures among burn and non-burn centers, similar to those performed for trauma care, should be encouraged.
In conclusion, more than three-quarters of significantly burned patients are treated at non-verified burn centers in the United States. Factors associated with treatment at verified centers include younger age, fewer comorbidities, burns to the hand, head and neck, and electrical injury. Currently, given that the only mechanism for assuring quality of burn care is through the ACS/ABA verification process, further studies are needed to determine the extent to which treatment quality is influenced by treatment location.