Articles: trauma.
-
In 2004, two large randomised multi-centre Australian clinical trials provided new information concerning optimal resuscitation for patients with traumatic brain injury (TBI). One examined hypertonic saline (HTS) and the other, albumin versus saline.( )For the first time in a randomised trial, hypertonic saline was tested for pre-hospital resuscitation of hypotensive patients with traumatic brain injury, and for the first time a resuscitation fluid trial measured long term neurological function as the primary outcome. Despite many potential advantages which may have much greater relevance in the hospital setting, in the paramedic based VICn trauma system, HTS did not improve neurological outcome compared to conventional pre-hospital fluid protocols. ⋯ Intriguingly however, the SAFE study also reported that within a subgroup of 492 patients with TBI, 28 day survival was superior in patients receiving saline. This subgroup result was not considered definitive, but a post hoc examination of the TBI patients currently in progress by the SAFE investigators, is expected to provide further guidance for clinicians. In the meanwhile, and until more high quality data is available, many clinicians are likely to prefer crystalloid resuscitation for trauma patients, and especially for trauma patients with brain injury.
-
In traumatic brain injury, cerebral hypoperfusion is associated with adverse outcome, particularly in the early phases of management. This has resulted in the increased use of drugs such as adrenaline, noradrenaline, dopamine and phenylephrine to augment or maintain systemic blood pressures at near normal levels. This is now part of standard practice and is endorsed by the Brain Trauma Foundation guidelines. ⋯ A paradigm shift from a "set and forget" philosophy to one of "titration against time" to achieve appropriate therapeutic targets is now required. In this context the rational use of vasoactive agents to optimise cerebral perfusion pressure may be employed. On the basis of limited animal and human evidence, noradrenaline appears to be the most appropriate catecholamine for traumatic brain injury, although definitive, targeted trials are required.
-
The impetus for cerebral hemodynamic monitoring in neurotrauma first arose from the original "talk and die" studies which described the group of head injured patients "who talk and then subsequently died". At necropsy, hypoxic or ischaemic brain damage was observed in a variable proportion of patients raising the possibility that systemic or cerebral hypoxia post trauma may have contributed to the poor neurological outcome. Improved understanding of the pathophysiology of neurotrauma influenced clinical practice in two ways: a) there was a plethora of monitoring modalities developed for evaluating cerebral hemodynamics and oxygenation and b) squeezing oxygenated blood through a swollen brain became the cornerstone of therapy in patients with head injury. ⋯ Although initial monitoring was largely confined to global indices of brain oxygenation, refinement in technology has made the measurement of oxygen tensions further down in the oxygen cascade at the level of the tissue possible and applicable by the bedside. Metabolic monitoring of the brain is now possible with the use of a variety of biochemical indices and with the availability of microdialysis. The purpose of this review is to examine the various modes of monitoring cerebral oxygenation, critically review the literature concerning their use in day to day intensive care practice, outline their limitations and define possible indications for their use.
-
Therapeutic hypothermia is a potentially dangerous treatment with a very narrow therapeutic index. It is of proven benefit in certain conditions, including post ventricular fibrillation cardiac arrest and intermediate severity neonatal asphyxia. ⋯ While it is clear that hypothermia decreases intracranial pressure, a major phase III trial demonstrated no improvement in neurological outcomes with hypothermia, in an unselected group of patient with severe head injury. More focused phase III trials are underway but until the results are known this treatment should not be offered to patients outside the context of a clinical trial.
-
Hypothermia for patients with severe traumatic brain injury (TBI) remains controversial despite a strong biological rationale and reasonable evidence from the literature. The "negative" Clifton study seems to have reduced enthusiasm for hypothermia, however the aim of this review is to analyse the evidence from all randomised controlled trials (RCT) and meta-analyses on this topic to determine whether there is adequate support for the view that hypothermia does improve outcome from TBI. The biological rationale for hypothermia is supported by animal and human mechanistic studies of TBI and human clinical studies of brain injury caused by out-of-hospital cardiac arrest. ⋯ Subsequent to these meta-analyses, a RCT was published which has confirmed that hypothermia is beneficial in a large group of TBI patients. When the published evidence is considered in total, even if hypothermia can't be justified in all TBI patients, if it is applied optimally in the most appropriate patients, hypothermia certainly improves outcome from TBI. If hypothermia is correctly applied (early, long and cool enough) in the optimal group of TBI patients (young with elevated ICP), there seems to be no doubt that hypothermia is effective in improving both survival and favourable neurological outcome from TBI.