Survival of trauma patients who have prehospital tracheal intubation without anaesthesia or muscle relaxants: observational study -- Data Supplement

Survival of trauma patients who have prehospital tracheal intubation without anaesthesia or muscle relaxants.

David Lockey, Gareth Davies, Tim Coats

In the UK it is current practice for paramedics to perform tracheal intubation on trauma patients when the airway is compromised and basic airway manoeuvres fail. Paramedics in Britain never use anaesthetic drugs or muscle relaxants to achieve intubation. Our anecdotal experience has been that patients who can be intubated without the use of drugs have a poor prognosis. This study was performed to investigate the mortality in a population of trauma patients who were intubated in the pre-hospital environment without the use of anaesthetic drugs.

Patients and Methods

We looked retrospectively at the database of a physician led helicopter emergency medical service which is specifically targeted at trauma patients. We identified patients that had been intubated without drugs by paramedics or doctors and recorded whether they survived to hospital discharge. All patients were attended by physicians but many were intubated by ground crew paramedics before arrival of the physician. Patients were removed from the scene to the nearest appropriate hospital by ground or air.

Results

In a six year period, from January 1990 to December 1996, 1623 patients were intubated outside hospital. 143 were excluded because they were not trauma patients. Of the remaining 1480 patients 492 were intubated without drugs. Of these, 56% were intubated by physicians and 44% by paramedics. Data was unavailable on 6 patients. Of the remaining 486 patients, one survived (0.2%). This individual had suffered a cardiac arrest after penetrating chest trauma and had a thoracotomy on scene to relieve pericardial tamponade and suture the myocardium.

Comment

Our results make us doubt the benefits of non-drug assisted intubation in trauma patients since mortality in our patient group was almost universal. UK paramedics have been performing non-drug assisted intubation for more than twenty years. A great deal of resource is put into teaching this skill. The intervention was mainly introduced to improve outcome in cardiac arrest but recently the effectiveness of intubation in this situation has been questioned [1]. In patients with severe trauma, airway compromise has been identified as a cause of preventable pre-hospital death in trauma [2]. Despite this and the fact that the importance of oxygenation is uncontroversial, we believe that non-drug assisted intubation is unhelpful because patients that can be intubated outside hospital rarely survive. Laryngoscopy and attempted intubation without drugs also has potential risks such as raising intracranial pressure [3] and unrecognised oesophageal intubation [4]. It may be that if patients with survivable injuries are to have their airways secured in the field, techniques other than non- drug assisted intubation may be indicated. Intubation with muscle relaxants outside hospital by doctors or paramedics may be required. Paramedics and nurses in parts of the United States already do this but failed intubation rates can be high [5]. The exact role of the UK paramedic is currently under discussion [6]. We question the value of tracheal intubation without drugs in trauma patients and suggest the entire issue of non-drug assisted pre-hospital intubation deserves further scrutiny during these discussions.

References

1. Guly UM, Mitchell RG, Cook R et al. Paramedics and technicians are equally successful at managing cardiac arrest outside hospital. BMJ 1995; 310: 1091-4.

2. Hussain IM & Redmond AD. Are pre-hospital deaths from accidental injury preventable? Br Med J 1994;308: 1077-80.

3. Burney RG & Winn R. Increased cerbrospinal fluid pressure during laryngoscopy and intubation for induction of anesthesia. Anesth Analg 1975 Sep-Oct;54(5):687-90.

4. Pelucio M, Halligan L & Dhindsa H. Out-of-hospital experience with the syringe esophageal detector device. Acad Emerg Med 1997 Jun;4(6):563-8.

5. . Blostein PA, Koestner AJ & Hoak S. Failed rapid sequence intubation in trauma patients: Esophageal tracheal Combitube is a useful adjunct. J Trauma 1998; 44(3): 534-6. Cooke MW. How much to do at the accident scene? BMJ 1999; 319: 1150 (30 October).