Prehospital Intravenous Fluid Administration is Associated With Higher Mortality in..

[medicRob]

Prehospital Intravenous Fluid Administration is Associated With
Higher Mortality in Trauma Patients: A National Trauma Data
Bank Analysis

Objective: Prehospital intravenous (IV) fluid administration is common in trauma patients, although little evidence supports this practice. We hypothesized
that trauma patients who received prehospital IV fluids have higher
mortality than trauma patients who did not receive IV fluids in the prehospital
setting.

Methods: We performed a retrospective cohort study of patients from the
National Trauma Data Bank. Multiple logistic regression was used with
mortality as the primary outcome measure. We compared patients with versus
without prehospital IV fluid administration, using patient demographics,
mechanism, physiologic and anatomic injury severity, and other prehospital
procedures as covariates. Subset analysis was performed based on mechanism
(blunt/penetrating), hypotension, immediate surgery, severe head injury, and
injury severity score.


Results: A total of 776,734 patientswere studied.Approximately half (49.3%)
received prehospital IV. Overall mortality was 4.6%. Unadjusted mortality
was significantly higher in patients receiving prehospital IV fluids (4.8% vs.
4.5%, P < 0.001).Multivariable analysis demonstrated that patients receiving
IV fluids were significantly more likely to die (odds ratio [OR] 1.11, 95%
confidence interval [CI] 1.05–1.17). The associationwas identified in nearly all
subsets of trauma patients. It is especially marked in patients with penetrating
mechanism (OR 1.25, 95% CI 1.08–1.45), hypotension (OR 1.44, 95% CI
1.29–1.59), severe head injury (OR 1.34, 95% CI 1.17–1.54), and patients
undergoing immediate surgery (OR 1.35, 95% CI 1.22–1.50).
Conclusions: The harm associated with prehospital IV fluid administration
is significant for victims of trauma. The routine use of prehospital IV fluid
administration for all trauma patients should be discouraged.

Discussion:

There are several inherent flaws in this study, most of them related to flaws in the National Trauma Data Bank. The National Trauma Data Bank (NTDB) is a compilation of information regarding traumatic injuries and subsequent outcomes in the United States. Emergency rooms, trauma centers, and other institutions participate in data submission, and in return, these agencies are given access to reports analyzing data regarding their own oeprations as well as trauma medicine in the United States as a whole. Researchers are also granted access to the data sets on an approval basis.

The Problems

While this system is useful in a variety of circumstances, it is not entirely appropriate for prehospital research as it does not take into account factors such as, "Response Times", "ALS/BLS Response", and several other factors.

One flaw that can be readily identified in this study is that the National Trauma Data Bank (NTDB) makes no differentiation between when an IV is started and when fluid is administered. Furthermore, we are not told the amount of fluid that is administered to the patients. Moreover, we there is no specification as to which medics started an IV on scene and delayed transport or whether the IVs were started in transport.

These are some very important parameters missing for this type of study.. especially for a study which concludes, "The harm associated with prehospital IV fluid administration is significant for victims of trauma. The routine use of prehospital IV fluid administration for all trauma patients should be discouraged."1


Here is a list of flaws outlined by Roguemedic in his blog

the mean systolic blood pressure of penetrating trauma patients who received cardiopulmonary resuscitation was 118 mmHg.

"That is higher than my blood pressure.

I am pretty sure that the AHA (American Heart Association) does not want anybody using CPR (CardioPulmonary Resuscitation) on people with good blood pressures. CPR is for people with no blood pressure (or for children with extremely low blood pressures).
Does this give us a hint about the reliability of the information used?
I think so."2

Another interesting finding by Rogue Medic:

"Even though the authors concluded that IV Starts produced worse outcomes, the procedure most strongly correlated with IV Starts was determined to have produced a protective effect. Most IV Start patients had MAST applied, while less than one fifth of one percent of the No IV Start patients had MAST applied.
Intubation (OR 1.57) and spinal immobilization (OR 1.42) were found to increase the odds of death by much more than IV Starts (OR 1.11) were increasing the odds of death.
If these numbers were valid, the increased odds of death should result in strongly worded warning letters on the hazards of spinal immobilization and intubation of trauma patients."2

I invite each of you to check out Rogue Medic's analysis of this paper over on his blog. There are several good points made, some bad. However, the basic consensus of the prehospital research community with regard to this study is that the data provided cannot be relied upon to make a decision as to whether or not prehospital IV fluids increase mortality in trauma patients, due to what seems to be erroneous data entry in the NTDB, lack of important parameters such as delays caused by IV starts on scene, amounts of fluid administered, as well as transport times.

http://www.medicalscg.de/files/tccc_haut_prehospital_iv_fluids_ann_surg_2011.pdf

Link to RogueMedic's article:
Click Me.



References

1. Haut ER, Kalish BT, Cotton BA, Efron DT, Haider AH, Stevens KA, Kieninger AN, Cornwell EE, 3rd, Chang DC. Prehospital intravenous fluid administration is associated with higher mortality in trauma patients: A national trauma data bank analysis. Ann Surg. 2010

2. Rogue Medic. Prehospital fluid administration is associated with higher mortality in trauma patients (parts i - iii). Rogue Medic. 2011;2011

 

[281mustang]

The blatant disregard for basic parmiters doesn't give me much faith in the study, to me it appears as if they developed their conclusion before the study began and modified it as needed. There is little reason to believe that a Medic starting a line en route and allowing permissive hypotension is going to increase mortality.

 

[medicRob]

The blatant disregard for basic parmiters doesn't give me much faith in the study, to me it appears as if they developed their conclusion before the study began and modified it as needed. There is little reason to believe that a Medic starting a line en route and allowing permissive hypotension is going to increase mortality.

The big thing that bothers me is that we do not know about transport times. Moreover, we don't know how many of those IV's were started on scene delaying transport and how long transport was delayed because of those IV starts. Whose to say it wasn't a delay in transport that caused the increased mortality?

 

[ffemt8978]

Given the fact that other "standard" treatment procedures have a higher mortality rate, and the fact that nearly every trauma victim gets more than an IV as part of their pre-hospital treatment, I have concerns that those other factors may be playing a bigger role in the mortality rate than the report reveals.

It appears as if they are taking a single treatment procedure and using it to prove their point, while at the same time ignoring or trying to explain away the rest of the procedures the patients receive as non-contributory.

 

[281mustang]

The big thing that bothers me is that we do not know about transport times. Moreover, we don't know how many of those IV's were started on scene delaying transport and how long transport was delayed because of those IV starts. Whose to say it wasn't a delay in transport that caused the increased mortality?

Exactly. It's already well known that starting two large bores on every trauma pt to flood them out is flawed and the idea of delaying surgery to stick them on scene should be a common sense issue.

Granted, although the endless complexity of the human body can result in some bewildering moments at times you're STILL going to give me some damn conclusive evidence to accept the idea that a BP of 40/20 with straight blood is superior to permissive hypotension. Some pie-in-the-sky study that addresses little yet pushes a conclusive across-the-board summary is simply not going to cut it.

 

[medicRob]

Some pie-in-the-sky study that addresses little yet pushes a conclusive across-the-board summary is simply not going to cut it.

This is what bothered me. It was not that the study had its flaws, all studies have flaws. It was that this study had the audicity to make such a claim as to say that we should discourage the routine use of prehospital IV fluids that appalled me.

Yes, I agree that we should use IV Fluids with discretion, there are certain situations that call for it (Dehydration for example) and certain situations where it might not be such a hot idea (Suspected triple A). Then again, any skill can be abused, right?

 

[281mustang]

Then again, any skill can be abused, right?

Absolutely.

This is not soley directed towards trauma fluid resuscitation, but too many times in life people try to label the tools themselves(literal ones...I'm feeling jaunty tonight) as "good" or "bad" based almost entirely on the application they are used for by some. View them as "powerful tools" and leave it at that, sheesh!

 

[mycrofft]

My STATISTICS 123 teacher would have slapped their wrists.

Two shames here. THe first is that they state a conclusion not exactly aligned with their hypotesis, which was:

"We hypothesized that trauma patients who received prehospital IV fluids have higher mortality than trauma patients who did not receive IV fluids in the prehospital setting".

Their recoomendation was to hesitate parenteral resuscitation in the field.

The hypothesis is a no brainer, people serious enough to get fluids, versus those not serious enough, ARE going to experience a higer mortality rate. Same as "The burn center is experiencing a mortality rate many times higher than that of the Dermatology department".

Break down cause of death established by postrmortem and relate it to parenteral admin in the field, including drugs given, conditon before IV, etc.

The second shame is that a cracked study like this (or any other similar) may have a ray of truth, but now the waters are muddied.

 

[Aidey]

I think the lack of data on the differences in on scene times were between the patients who got various interventions seriously undermines the study. I think the best thing it does is show that more studies of higher quality need to be done to draw any solid conclusions.

I think overall this also illustrates the problem with researching pre-hospital interventions - there are a lot of variables that the researchers can't manage, and will never be able to.

A simple study I would like to see done is a comparison between CBC values, amount of IV fluid administration, and outcome. I'm just curious how strong of a correlation there would be (if any).