Prof R Robinson Associate Editor BMJ

Dear Prof Robinson,

Re: Paper: Survival of trauma patients who have pre-hospital tracheal intubation without anaesthesia.

We have attempted to answer all of the points raised by yourself and the two reviewers and indicated where changes have been made to the text.

Points in your covering letter:
 

1.We completely agree that the main point of this paper is the poor outcome for this patient group.
2.We do not want to suggest that drug assisted intubation is better because as you point out we have not presented any data on this patient group. We have amended the text appropriately. We point out that some trauma systems use drugs to intubate in the pre-hospital environment but that we have focussed only on non-drug assisted intubation as this is the standard practice of UK paramedics.
3.We have amended the title of the paper to include the design (observational).
Points raised by MJ Campbell:
4.Setting. We have briefly mentioned most aspects of setting - type, aim and staffing of service, the fact that the area served is urban and the rationale for hospital destination of removed patients.
5.Record keeping is excellent in this system. Database is completed after every mission by a registrar. Two data collection officers ensure that missing data is completed and that discharge and follow up data are properly entered. A quality control system to cheek data reliability is in operation. The use of drugs is always recorded on the mission sheet and no patient will have received drugs in the no-drugs group.
6.The second sentence now reads 'data regarding survival.'
7.Survival was defined as survival to hospital discharge. One patient survived and is still alive. The survival of patients intubated with drugs is addressed above (point 2). We do have this data but as explained above we are not attempting to compare the two groups.
8.Patients were intubated without drugs for two reasons. (i) because paramedics judged the airway to be compromised and non-drug assisted intubation is their only option or (ii) where a physician was present, airway was judged unsafe and there were no signs that resistance to intubation was likely (coughing, signs of consciousness). This would put the patients in a high risk group but that is really the point of the paper i.e. that if one can intubate without drugs the prognosis is poor.
9.Any intubation carries a risk of oesophageal intubation and non drug assisted intubation probably carries more of a risk because the view is often worse. We do not suggest that oesophageal intubation is in any way responsible for the poor survival. We only mention this issue because even where drugs are used major problems are reported.
10.References checked.
The points raised by Dr Zimmermann.
11.Opening comments.. The first sentence is a correct summary of our aim. The second sentence is also true but, as mentioned above, we are not aiming to answer this question. This short report merely documents the lack of efficacy of current UK practice (intubation without drugs) in one geographical area. The paper quoted is of dubious quality.
12.Both of these issues are covered above.
13.We have not transferred details of cause of death of these patients from our database. However we have excluded 143 patients because they were not trauma patients. These patients included various conditions e.g. drowning and primary cardiac arrest. The trauma patients died predominantly of head and multiple injuries.
14.At the time of this study the intubation success rate in our system was 97.7%. We did not attempt to compare the ability of paramedics and physicians to intubate. We have not attempted to document the problems encountered when intubating without drugs, merely the survival of those who could be intubated.
15.The drugs used for drug assisted intubation in this system were Etomidate, Suxamethonium and an Opioid. In the study group however, no drugs were used by definition.
16.These points are mostly covered in the text. We did not feel that description of dispatch criteria and helicopter Vs. ground statistics were relevant to the report and would also make it too long.
17.(Other comments section). On scene thoracotomy: there is one case report in the literature from the US. This centre has a report of four survivors in press with the Journal of Trauma.
18.18. This point is dealt with above.
19.The last point: We do not answer the question of whether patients should be intubated with drugs in the pre-hospital setting by paramedics because this is not our aim. We do however question the effectiveness of an intervention which is current practice and costly in terms of resource.

Yours sincerely,
Dr David Lockey.