Cohort
Ram Nirula, MD, MPH, FACS, Ronald Maier, MD, Ernest Moore, MD, Jason Sperry, MD, MPH,Scoop and Run to the Trauma Center or Stay and Play Local Hospital: Hospital Transfer’s Effect on Mortality
The Journal of TRAUMA Injury, Infection, and Critical Care
Volume 69, Number 3, September 2010, pages 595-601
- Submitted by:Michael Mancera - resident physician
- Institution:Grand Rapids Medical Education Partners/Michigan State University
- Date submitted:17th April 2011
1
Objectives and hypotheses
1.1
Are the objectives of the study clearly stated?
Yes - to analyze whether initial triage of critically injured patients to a nontrauma center (NTC) is associated with increased mortality.
2
Design
2.1
Is the study design suitable for the objectives?
This is a secondary analysis of data collected in the context of an ongoing large multicenter prospective cohort study.
2.2
Who / what was studied?
The Glue Grant Trauma Database of severely injured patients was analyzed. Mortality risk for patients who had an intermediate stop at another facility was compared with patients triaged directly from the scene to the TC.
Patient demographics, time from injury to TC arrival, resuscitation volume, transfusions, head injury, initial systolic blood pressure, co-morbidities, and injury severity were included as confounders in a multivariate logistic regression model.
Patient demographics, time from injury to TC arrival, resuscitation volume, transfusions, head injury, initial systolic blood pressure, co-morbidities, and injury severity were included as confounders in a multivariate logistic regression model.
2.3
Was a control group used if appropriate?
No control group. Patients transported directly to a trauma center were compared to those who were first taken to a non-trauma center and then transferred to a trauma center.
2.4
Were outcomes defined at the start of the study?
Yes, in-hospital mortality.
2.5
Was this the right sample to answer the objectives?
This report focuses on patients admitted to any one of eight participating institutions
during the interval April 2004 through June 2007. Criteria for enrollment were aged 16 years and older, blunt trauma, arrival to hospital within 6 hours of injury, either hypotension (90) or an elevated base deficit (6), blood transfusion within 12 hours of injury, any body region exclusive of the brain with an Abbreviated Injury Scale score 2, and an intact cervical spinal cord to exclude those with isolated severe head injuries or spinal cord injuries, respectively. Standard operating procedures for enrolled patients are used to minimize therapeutic disparities between participating centers that would influence outcomes.
during the interval April 2004 through June 2007. Criteria for enrollment were aged 16 years and older, blunt trauma, arrival to hospital within 6 hours of injury, either hypotension (90) or an elevated base deficit (6), blood transfusion within 12 hours of injury, any body region exclusive of the brain with an Abbreviated Injury Scale score 2, and an intact cervical spinal cord to exclude those with isolated severe head injuries or spinal cord injuries, respectively. Standard operating procedures for enrolled patients are used to minimize therapeutic disparities between participating centers that would influence outcomes.
2.6
Were patients at a uniformly early stage in their disease?
Yes - 1,112 patients, of whom 318 (29%) were initially triaged to a non-trauma center.
2.7
If subgroups with important prognostic differences are already known were there adjustments made for these prognostic factors?
Yes. There were 1,112 patients suffering from major blunt trauma of whom 91 (8.2%) died within 24 hours of injury. Seven of the patients did not have data describing whether they were directly transported from the scene to the trauma center or were first brought to an non-trauma center and then to the trauma center and were excluded from the analysis leaving 1,105 patients.
2.8
Is the study large enough to achieve its objectives? Have sample size estimates been performed?
Yes - patient demographics, time from injury to TC arrival, resuscitation volume, transfusions, head injury, initial systolic blood pressure, co-morbidities, and injury severity were included as confounders in a multivariate logistic regression model.
2.9
Were all subjects accounted for?
Yes.
2.10
Were all appropriate outcomes considered?
2.11
Has ethical approval been obtained if appropriate?
3
Measurement and observation
3.1
Is it clear what was measured, how it was measured and what the outcomes were?
Patients who underwent direct triage to a level I Trauma center were compared with patients who were first seen at a non-trauma center hospital and then transferred to a trauma center. Patient characteristics, injury severity, physiology, and underlying medical condition between trauma center and non-trauma center patients were compared in univariate analysis with Student’s t test for continuous variables and x2 analysis or Fisher’s exact test where appropriate for categorical variables with alpha set at 0.05
3.2
Was the assessment of outcomes blinded?
No, this was a non-blinded retrospective cohort study.
3.3
Was follow up sufficiently long and complete?
Yes. Patients were followed for their in-patient hospital stay, no further follow up needed.
3.4
Are the measurements valid?
Yes. After adjusting for confounders, patients taken to a non-trauma center had an associated increase in prehospital crystalloids (4.2 L vs. 1.4 L, p 0.05) and a 12-fold increase in blood transfusions (60% vs. 5%, p 0.001). Age, injury severity score, Acute Physiology and Chronic Health Evaluation II score, and time
from injury to trauma center arrival were independent predictors of mortality. The odds of death were 3.8 times greater (95% CI,1.6 –9.0) when patients were initially triaged to a nontrauma facility.
from injury to trauma center arrival were independent predictors of mortality. The odds of death were 3.8 times greater (95% CI,1.6 –9.0) when patients were initially triaged to a nontrauma facility.
3.5
Are the measurements reliable?
Yes. The odds of death were 3.8 times greater (95% CI,1.6 –9.0).
3.6
Are the measurements reproducible?
Yes
4
Presentation of results
4.1
Are the basic data adequately described?
Time from injury to arrival at the TC was categorized in 30 minutes intervals, pre-TC blood infused was categorized in 600 mL volumes and volume of pre-trauma center fluid infused was categorized as 500 mL, 500 mL to 2 L, 2 L to 4 L, and 4 L. Other covariates were categorized into clinically relevant cutoff points. Whether a patient was directly transported to the TC or was first seen at a non-trauma center and then transferred to a trauma center was categorized as the binary independent variable. Covariates that were associated with in-hospital mortality or were associated with transfer to the trauma center were included in a multivariate logistic regression analysis with mortality as the dependent variable and transfer to TC as the independent variable. Additional covariates that are believed to be clinically relevant such as comorbidities as measured by Acute Physiology and Chronic Health Evaluation (APACHE)score were also included in the model. Controlling for these covariates, the odds of death for patients who were transferred from a non-trauma center to a trauma center was compared with the odds of death for similar patients who were transported directly to the trauma center.
4.2
Are the results presented clearly, objectively and in sufficient detail to enable readers to make their own judgement?
Yes, see Tables 1 and 2
4.3
How large are the effects within a specified time?
The odds of death were 3.8 times greater (95% CI, 1.6–9.0) when patients were initially triaged to a nontrauma facility.
4.4
Are survival curves presented?
Yes.
4.5
Are the results internally consistent, i.e. do the numbers add up properly?
5
Analysis
5.1
Are the data suitable for analysis?
Yes - patient characteristics, injury severity, physiology, and underlying medical condition between TC and NTC patients were compared in univariate analysis with Student's t test for continuous variables and [chi]2 analysis or Fisher's exact test where appropriate for categorical variables with alpha set at 0.05
5.2
How precise are the prognostic estimates?
Yes - this was a secondary analysis of data collected in the context of an ongoing large multicenter prospective cohort study whose primary objective is to evaluate the relationship between the inflammatory response to injury and posttraumatic multiple organ failure
5.3
Are the methods appropriate to the data?
Yes.
5.4
Are any statistics correctly performed and interpreted?
6
Discussion
6.1
Are the results discussed in relation to existing knowledge on the subject and study objectives?
Results were discussed in an appropriate manner.
6.2
Is the discussion biased?
No, balanced approach
7
Interpretation
7.1
Are the author's conclusions justified by the data?
Yes, The odds of death were 3.8 times greater (95% CI, 1.6 – 9.0) when patients were initially triaged to a nontrauma facility.
7.2
What level of evidence has this paper presented? (using CEBM levels)
2b
7.3
Does this paper help me to answer my problem?
Yes, we can conclude that interhospital transfer of severely injured patients is associated with an increased risk of mortality. The precise reason for this remains unclear, but it may be related to delays in definitive injury control with suboptimal resuscitation related to the transfer and subsequent trauma team management.
8
Implementation
8.1
Can any necessary change be implemented in practice?
This study would suggest transporting all trauma patients directly to a trauma center, which may not be practical based on location/distance from a trauma center.
8.2
What aids to implementation exist?
Improved systems of transport are in place to physically get trauma patients to a regional trauma center, both ground and air transport.
8.3
What barriers to implementation exist?
Distance to a trauma center is the main barrier, it may take several hours of transportation from certain locations to the nearest trauma center. Another important factor would be whether time-sensitive interventions not able to be completed by EMS in the field need to be performed at he closest facility, for example chest tube placement, central line placement, advanced airway stabilization. In such cases transportation to the nearest facility may be the most beneficial course for these patients.
8.4
Are the study patients similar to your own?
Yes. I see trauma patients at a trauma center, some of which are transported directly to our facility, others are transferred from a non-trauma center.
8.5
Does the paper give any conclusions that will affect what you will offer or tell your patient?
No.