Value of the prospective 'before and after' study as a methodology to evaluate outcome in a trauma centre

The association between trauma system and trauma center components and outcome in a mature regionalized trauma system

BACKGROUND

Regionalized trauma systems have been shown repeatedly to improve the outcome of seriously injured patients. However, we do not have data regarding which components of these systems have the most impact on outcome and to what degree. The objective of this study was to understand the association between various components that make up a trauma system and outcome.

METHODS

Surveys were administered to trauma directors at 59 hospitals in the province of Quebec, Canada. Data from the surveys were then linked with specific outcome variables obtained from a regionalized trauma database. Specific outcomes were assigned to trauma system- and in-hospital-based components after controlling for injury severity.

RESULTS

Over 4.8 years, 72,073 patients met inclusion criteria. Components found to affect survival after risk adjustment were prehospital notification (OR, 0.61; 95% CI, 0.39-0.94) and the presence of a performance improvement program in that hospital (OR, 0.44; 95% CI, 0.20-0.94). Increased patient volume was associated with a reduction in risk-adjusted mortality (OR, 0.98; 95% CI, 0.97-0.99). Tertiary trauma centers were also associated with a reduction in risk-adjusted mortality compared with both secondary and primary centers (OR, 0.68; 95% CI, 0.48-0.99).

CONCLUSIONS

Improvements in outcome in a regionalized trauma system are secondary to a combination of elements, as well as to the interplay of these elements on each other. Prehospital notification protocols and performance improvement programs appear to be most associated with decreased risk-adjusted odds of death.

Trauma systems--state of the art

Trauma is an inevitable consequence of the lives we lead. There are many approaches to dealing with it but an ideal system, universally applicable, probably does not exist because of the national variations in social, economic, cultural and geographical characteristics. Many countries are beginning to recognise that the 'systems' they have in place for dealing with the burden of trauma are seriously deficient and that this situation cannot be allowed to continue into the new millennium. However, it is highly unlikely that in the near future. governments will suddenly find substantial extra finance for trauma care or the implementation of new systems. Throughout many countries, the individual components of trauma care systems are in place but, for whatever reasons, there is a lack of integration, which results in suboptimal care. The system we all should be aiming for is one of closer communication and greater cooperation. By taking into account community and national needs, available resources, and adapting what is currently in place it should then be possible to create 'a set of things working together as parts of a trauma mechanism'.

Trauma center maturation: quantification of process and outcome

BACKGROUND AND OBJECTIVE

The regional trauma system with the trauma center as its center is a model for health care networks. However, trauma center maturation has not been defined in the literature. The authors' hypothesis was that maturation of the trauma center would affect quantitatively both process and patient outcome.

MATERIALS AND METHODS

A total of 15,303 trauma patients were admitted from 1987 to 1995. Annual admissions increased from 813 to 2669. Resources were generated as patient volume increased. Time to the operating room, length of stay, and complications were determined. TRISS methodology was used to calculate z scores and w values to compare actual with predicted mortality rates.

RESULTS

Time to the operating room for laparotomy decreased from 62+/-73 to 35+/-47 minutes, from 32+/-32 to 20+/-17 minutes in hypotensive patients, and for craniotomy decreased from 88+/-54 to 67+/-49 minutes. The incidence of infectious, airway, neurologic, orthopedic, respiratory, gastrointestinal, and procedure-related complications declined significantly. Z scores and w values increased for penetrating and blunt injuries. Deaths for patients with ISS >15 declined significantly. Hospital length of stay decreased for all ranges of injury severity.

CONCLUSIONS

As the trauma center matured, the process of delivering patient care became more efficient. The result was improved survival, fewer complications, and a shorter length of stay.

Impact of a dedicated trauma service on the quality and cost of care provided to injured patients at an urban teaching hospital

BACKGROUND

To determine the impact of a dedicated trauma service on cost and quality of care in an urban teaching hospital, a before-and-after study was designed. The key elements of the trauma service were dedicated in-house trauma attending surgeons and residents, and continuity and integration of trauma care.

METHODS

Injury Severity Scores and probabilities of survival for each patient were calculated from the hospital International Classification of Diseases, Ninth Revision, codes, and individual patient costs were estimated from charges using the Medicare Cost Report.

RESULTS

The trauma service resulted in a significant increase in the severity of injuries. There was a highly significant (p<0.001) increase in the mean probability of death (from 0.16 to 0.21). There was no change in actual mortality. Although the mean cost of care increased by 16.6%, there were small reductions in the cost of care of the most severely injured patients.

CONCLUSION

A dedicated trauma service has a positive impact on the quality of care.

Resource utilization by injured automobile occupants and pedestrians

BACKGROUND

This study was designed to test the hypothesis that the hospital resources utilized in treating pedestrian trauma would be significantly greater than that for automobile occupants. This was based on previous studies that showed that the demographic features and patterns of injury sustained by the pedestrian population were significantly different from that of automobile occupants.

METHODS

A hospital-based study was designed utilizing retrospective analysis of a prospective trauma database. All primary retrievals of pedestrians (n=547) and automobile occupants (n=597) involved in accidents in Central Sydney from mid-1990 to mid-1995 were included. The length of hospital stay, use of the intensive care unit (ICU) and visits to the operating theatre (Standard Resource Cost) were compared.

RESULTS

The age and injury severity scores were significantly higher for the pedestrian group. The length of stay (days) for the pedestrians (mean, 12 SD 14; median, 7 interquartile range (IQR) 13), was significantly higher (P < 0.0001 ) than that for the automobile occupants (mean, 7 SD 11; median, 2 IQR 6). The ICU utilization (days) for the pedestrians (mean, 1.3 SD 4.0; median, 0) was significantly higher (P < 0.0001) than that of the automobile occupants (mean, 0.6 SD 2.9; median, 0). The average operating theatre utilization per pedestrian (0.65 visits) exceeded that of automobile occupants (0.43) by 50% (P < 0.0001).

CONCLUSIONS

The study confirms that the acute care of pedestrian injury utilizes more hospital resources than that of automobile occupants. Resources should be allocated to meet this need both in terms of hospital reimbursement and overall directives in public health policy.

Rural Hospital Transfer Patterns before and after Implementation of a Statewide Trauma System

OBJECTIVE

To evaluate trauma transfer practices in rural Oregon before and after implementation of a statewide trauma system.

METHODS

A pre- vs post-system implementation (historical control) analysis of trauma transfer practices was performed using a sample of rural ED trauma patients from 4 Level-3 and 5 Level-4 trauma hospitals. Medical records of patients with specific index injury diagnoses in 4 anatomic regions (head, chest, liver/ spleen, and femur/open-tibia) were reviewed for a 3-year period before statewide trauma system implementation and 3 years after hospital trauma designation.

RESULTS

Of 1,057 patients entered into the database, 532 were evaluated during the pre-system period and 525 were evaluated during the post-system period. Overall, 47% had head injuries, 34% had chest injuries, 23% had femur/open-tibia injuries, and 12% had spleen/liver injuries. There were 142 (13%) patients with an injury in >1 index area. After trauma system implementation, there was a significant increase in the proportion of ED trauma patients transferred from Level-4 trauma hospitals (32% vs 68%, p < 0.001), with a corresponding decrease in the number of hospital admissions to these facilities (63% to 29%, p < 0.001). Significant increases in the proportion transferred from Level-4 trauma hospital EDs were noted for all index injury categories (p < 0.001). Trauma patients presenting to Level-4 EDs were significantly more likely to be transferred to Level-2 facilities (66% vs 82%, p = 0.030), while patients at Level-3 facilities were significantly more likely to be transferred to Level-1 centers (2% vs 14%, p = 0.002) following trauma system implementation. Multiple logistic regression modeling indicated that implementation of the statewide trauma system was an independent predictor of rural trauma patient transfer from Level-4 hospitals, while transfers from Level-3 facilities were dependent on type of injury.

CONCLUSION

Implementation of the Oregon statewide trauma system was associated with a redistribution of rural trauma patients to trauma hospitals with greater therapeutic resources.

Studies of avoidable factors influencing death: a call for explicit criteria

OBJECTIVE

To analyse studies evaluating cases of potentially "avoidable" death.

DESIGN

The definitions, sources of information, and methods were reviewed with a structured protocol. The different types of avoidable factors,--that is, deficiencies in medical care that may have contributed to death--were categorised. The presence of explicit classifications and standards was examined. basic criteria for quality of the studies were defined and the numbers of studies fulfilling these criteria were assessed.

SETTING AND PARTICIPANTS

65 studies, published during 1988-93 in peer reviewed medical journal for which the title, or abstract, or both indicated that they had analysed potentially avoidable factors influencing death. Studies analysing aggregated data only, were not included.

RESULTS

Only one third of the studies fulfilled basic quality criteria,--namely, that the avoidable factors examined should be defined and the sources of information and people responsible for the judgements presented. The definitions used comprised two levels, one stating that there had been errors in management (process) and the other that the errors may have contributed to the deaths (outcome). Only 15% of the studies explicitly defined what type of factors they had looked for and 8% referred to specified standards of care.

CONCLUSIONS

Studies of avoidable factors influencing death may have considerable potential as part of a system of improving medical care and reducing avoidable mortality. At present, however, the results from different studies are not comparable, due to differences in materials and methods. There is a need to improve the quality of the studies and to define standardised explicit definitions and classifications.

Outcome of patients with neurotrauma: the effect of a regionalized trauma system

A system of regionalized trauma care was introduced to Sydney in early 1992. This study was carried out to assess the effect of regionalization on the outcome of patients suffering major head injury within the central Sydney area. A prospective before and after study extending over 3 years and centred on the time of designation of Royal Prince Alfred Hospital (RPAH) as a trauma centre, was the methodology used. The study group consisted of all patients admitted with head injury (Glasgow Coma Score < 9; admission systolic blood pressure > 90 mmHg; Injury Severity Score > 15) to RPAH from the central Sydney area. Outcome criteria include survival rates, transfer numbers, and time to definitive neurosurgical care. Fifty patients were entered during the first 18 months of the study, and 38 during the second 18 months. Fifteen in the first group required evacuation of intracranial mass lesions, as did nine in the second group. The overall mortality fell from 42 to 26% (P = 0.13). During the study period there were 77 primary retrievals and 20 required evacuation of mass lesions. The median time from injury to commencement of operation in these patients was 2 h 13 min (range 1 h 3 min-5 h 35 min). There were 11 transfers, four requiring craniotomy. The median time from injury to surgery was 7 h 24 min (range 3 h 2 min-10 h 25 min; P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)