Efficacy of pre-hospital interventions for the management of severe blunt head injury

Prehospital management of traumatic brain injury

The aim of this study was to review the current protocols of prehospital practice and their impact on outcome in the management of traumatic brain injury. A literature review of the National Library of Medicine encompassing the years 1980 to May 2008 was performed. The primary impact of a head injury sets in motion a cascade of secondary events that can worsen neurological injury and outcome. The goals of care during prehospital triage, stabilization, and transport are to recognize life-threatening raised intracranial pressure and to circumvent cerebral herniation. In that process, prevention of secondary injury and secondary insults is a major determinant of both short- and longterm outcome. Management of brain oxygenation, blood pressure, cerebral perfusion pressure, and raised intracranial pressure in the prehospital setting are discussed. Patient outcomes are dependent upon an organized trauma response system. Dispatch and transport timing, field stabilization, modes of transport, and destination levels of care are addressed. In addition, special considerations for mass casualty and disaster planning are outlined and recommendations are made regarding early response efforts and the ethical impact of aggressive prehospital resuscitation. The most sophisticated of emergency, operative, or intensive care units cannot reverse damage that has been set in motion by suboptimal protocols of triage and resuscitation, either at the injury scene or en route to the hospital. The quality of prehospital care is a major determinant of long-term outcome for patients with traumatic brain injury.

Prehospital Hypoxia Affects Outcome in Patients With Traumatic Brain Injury: A Prospective Multicenter Study

BACKGROUND

The goals of this study were to determine the incidence and duration of hypotension and hypoxia in the prehospital setting in patients with potentially survivable brain injuries, and to prospectively examine the association of these secondary insults with mortality and disability at hospital discharge.

METHODS

Trauma patients with suspected brain injuries underwent continuous blood pressure and pulse oximetry monitoring during helicopter transport. Postadmission inclusion criteria were (1) diagnosis of acute traumatic brain injury (TBI) confirmed by computed tomography (CT) scan, operative findings, or autopsy findings; and (2) Head Abbreviated Injury Scale (AIS) score of > or = 3 or Glasgow Coma Scale (GCS) score of < or = 12 within the first 24 hours of admission. Patients were excluded with (1) no abnormal intracranial findings on the patient's CT scan; (2) determination of a nonsurvivable injury (based on an AIS score of 6 for any body region; or, (3) death in less than 12 hours after injury. Primary outcome measures included mortality and Disability Rating Scale score at discharge.

RESULTS

We enrolled 150 patients into the study. Fifty-seven patients had at least one secondary insult; 37 had only hypoxic episodes, 14 had only hypotensive episodes, and 6 patients had both. Demographics and injury characteristics did not differ between those with and those without secondary insults. The mortality for patients without secondary insults was 20%, compared with 37% for patients with hypoxic episodes, 8% for patients with hypotensive episodes, and 24% for patients with both. The Disability Rating Scale score at discharge was significantly higher in patients with secondary insults. Using multivariate analysis, the calculated odds ratio of mortality caused by prehospital hypoxia after head injury was 2.66 (p < 0.05).

CONCLUSIONS

Secondary insults after TBI are common, and these insults are associated with disability. Hypoxia in the prehospital setting significantly increases the odds of mortality after brain injury controlled for multiple variables.

The Management Of Head Injuries On Military Operations

The management of head injured patients has recently been reviewed with the development of civilian guidelines for best practice. These are common injuries which often have significant sequelae for patients and costs for health care providers. Evolving civilian standards of care have implications for military medicine which is often practised in challenging environments. Considerable planning and resources are necessary to meet these standards in an operational environment. The current standards and the problems of applying them in an operational theatre are discussed.

Description d'un protocole de prise en charge préhospitalière du traumatisé crânien grave

OBJECTIVES

To analyze the frequency of systemic factors leading to secondary brain insults in victims of serious head trauma in a prehospital setting and to evaluate a protocol for the advanced prehospital emergency care by mobile intensive care unit (i.e., the French Samu-Smur system).

STUDY DESIGN

Prospective study, over a period of 24 months.

PATIENTS AND METHODS

This prospective study involved 60 victims of severe head injuries (with the exception of polytrauma patients). Tracheal intubation was performed on each patient under direct laryngoscopy and after induction of anaesthesia (fentanyl-etomidate-rocuronium). Controlled ventilation and vascular loading (objectives: SpO(2) >or= 97%, PETCO(2) between 30 and 35 mmHg, SAP >or= 90 mmHg) were administered.

RESULTS

Hypoxaemia was found to be the most frequent cause of secondary insults (57% of patients with SpO(2) < 97%). In the case involving an accident that occurred 17 km from the hospital (with extremes of 6-65 km), the speed of medical intervention was note-worthy: tracheal intubation was performed 50 min after the accident, and the patient was admitted into a trauma centre 101 min after impact (median). However, faster intervention could be obtained if the transmission of the alert was improved. The conditions under which the tracheal intubation was performed were found to be satisfactory (difficult intubation 1.6%) without deteriorating the haemodynamic status. This is probably related to the use of muscle relaxants and the choice of etomidate as the first line hypnotic in the prehospital emergency care.

Incidence of transient hypoxia and pulse rate reactivity during paramedic rapid sequence intubation

STUDY OBJECTIVE

We determine the incidence of desaturation and pulse rate reactivity during paramedic rapid sequence intubation of patients with severe head injuries (Glasgow Coma Scale score <or=8).

METHODS

Adult patients with severe head injuries had recording oximeter-capnometers applied before rapid sequence intubation. Desaturation was defined as a reduction in oxygen saturation (Spo(2)) to less than 90% from an initial Spo(2) of greater than or equal to 90% or a decrease from a baseline of less than 90%. Event records were analyzed with emergency medical services (EMS) run sheets and debriefing reports.

RESULTS

Thirty-one (57%) of 54 patients demonstrated desaturation during rapid sequence intubation. Twenty-six (84%) of these 31 events occurred in patients whose initial Spo(2) value with basic airway skills was greater than or equal to 90%. The median duration of desaturation was 160 seconds (interquartile range 48 to 272 seconds), and the median decrease in Spo(2) was 22%. Six (19%) patients experienced marked bradycardia (pulse rate <50 beats/min) during desaturation events. Paramedics described rapid sequence intubation as "easy" in 26 (84%) of 31 patients with desaturation.

CONCLUSION

Out-of-hospital rapid sequence intubation by paramedics was complicated by a concerning incidence of desaturation and bradycardia. Paramedic reports did not reflect the presence of these concerning derangements. Most patients had acceptable Spo(2) values before rapid sequence intubation. An effective strategy for preoxygenation is needed before it can be concluded that rapid sequence intubation is of value in the out-of-hospital care of patients with serious closed head injury.