Management of severe head injury: institutional variations in care and effect on outcome

Multimodal monitoring in traumatic brain injury: current status and future directions

Traumatic brain injury (TBI) remains a major cause of morbidity and mortality, particularly in young people. Despite encouraging animal studies, human trials assessing the use of pharmacological agents after TBI have all failed to show efficacy. Current management strategies are therefore directed towards providing an optimal physiological environment in order to minimize secondary insults and maximize the body's own regenerative processes. Modern neurocritical care management utilizes a host of monitoring techniques to identify or predict the occurrence of secondary insults and guide subsequent therapeutic interventions in an attempt to minimize the resulting secondary injury. Recent data suggest that the use of protocolized management strategies, informed by multimodality monitoring, can improve patient outcome after TBI. Developments in multimodality monitoring have allowed a movement away from rigid physiological target setting towards an individually tailored, patient-specific, approach. The wealth of monitoring information available provides a challenge in terms of data integration and accessibility and modern software applications may aid this process.

What is the empirical evidence that hospitals with higher-risk adjusted mortality rates provide poorer quality care? A systematic review of the literature

Background

Despite increasing interest and publication of risk-adjusted hospital mortality rates, the relationship with underlying quality of care remains unclear. We undertook a systematic review to ascertain the extent to which variations in risk-adjusted mortality rates were associated with differences in quality of care.

Methods

We identified studies in which risk-adjusted mortality and quality of care had been reported in more than one hospital. We adopted an iterative search strategy using three databases – Medline, HealthSTAR and CINAHL from 1966, 1975 and 1982 respectively. We identified potentially relevant studies on the basis of the title or abstract. We obtained these papers and included those which met our inclusion criteria.

Results

From an initial yield of 6,456 papers, 36 studies met the inclusion criteria. Several of these studies considered more than one process-versus-risk-adjusted mortality relationship. In total we found 51 such relationships in a widen range of clinical conditions using a variety of methods. A positive correlation between better quality of care and risk-adjusted mortality was found in under half the relationships (26/51 51%) but the remainder showed no correlation (16/51 31%) or a paradoxical correlation (9/51 18%).

Conclusion

The general notion that hospitals with higher risk-adjusted mortality have poorer quality of care is neither consistent nor reliable.

Ventilator-associated pneumonia in severe traumatic brain injury

INTRODUCTION

Pneumonia is an important cause of morbidity following severe traumatic brain injury (TBI). However, previous studies have been limited by inclusion of specific patient subgroups or by selection bias. The primary objective of this study was to describe the incidence, risk factors for, and outcome of ventilator-associated pneumonia in an unselected population-based cohort of patients with severe TBI. An additional goal was to define the relationship of ventilator-associated pneumonia (VAP) with nonneurological organ dysfunction.

METHODS

A prospective, observational cohort study was performed at Foothills Medical Centre, the sole adult tertiary-care trauma center servicing southern Alberta. All patients with severe TBI requiring ventilation for more than 48 hours between May 1, 2000 and December 30, 2002 were included.

RESULTS

A total of 60 patients (45%) acquired VAP for an incidence density of 42.7/1000 ventilator days. Patients with polytrauma were at higher risk (risk ratio 1.7, 95% confidence interval, 0.9-3.1) for development of VAP than those with isolated head injury. Development of VAP was associated with a significantly greater degree of nonneurological organ system dysfunction. Although VAP was not associated with increased hospital mortality, patients who developed VAP had a longer duration of mechanical ventilation (15 versus 8 days, p < 0.0001), longer intensive care unit (17 versus 9 days, p < 0.0001) and hospital (60 versus 28 days, p = 0.003) lengths of stay, and more often required tracheostomy (35 versus 18%, p = 0.003).

CONCLUSIONS

VAP occurs frequently and is associated with significant morbidity in patients with severe TBI.

Not if but when; no longer why but how

There is accruing evidence that information technology can improve patient health care, with several trials of technology showing smaller numbers of medication errors, or can provide earlier detection of adverse events. Critics of this type of research point out that better resolution of events is of no value unless their direct management influences clinical outcome. Nevertheless, indirect evidence is available, such as reports indicating the importance of providing specialist neuro-critical care in the management of patients with traumatic brain injury. These studies do not indicate which aspects of critical care management are crucial, but management aimed at the earlier detection and treatment of adverse events must be partly responsible. We continue to hope for definitive controlled trial evidence that information technology-led management yields improved patient outcome, but our experience so far of funding and conducting such studies has been poor. There is no question that we need better monitoring and event detection technology for health care and that we need more research into optimising that technology, but should their adoption depend on large-scale clinical trials? Perhaps now the questions we need to focus upon are no longer if but when, and no longer why but how.

Subdural intracranial pressure monitoring in severe head injury: clinical experience with the Codman MicroSensor

BACKGROUND

Our main objective was to study the clinical outcome and complications of the subdural ICP monitoring with the CMS (Johnson and Johnson Medical Ltd, Raynhan, MA) in severe head injury.

METHODS

A retrospective analysis of patients with head injury with a GCS score of 8 or less was performed. Patients with severe systemic injury with hypotension (systolic blood pressure of <90 mm Hg on admission), a GCS score of 3 with fixed and dilated pupils after resuscitation, a GCS score of 3 to 4 whose family refused aggressive treatment, and those who were dead on arrival were excluded from this study. During the period from January 1997 to April 2004, 120 patients with severe head injuries were included and met criteria for insertion of a subdural ICP monitoring device (CMS).

RESULTS

A total of 120 patients (84 males and 36 females), aged 16 to 80 years old (mean, 43.8 +/- 14.4), were enrolled in the study. The average duration of ICP monitoring device use was 7.6 +/- 0.4 days (range, 2-14 days). The overall clinical outcomes of these patients were as follows: mortality rate, 13.5%; percentage of unfavorable outcomes, 17.3%; percentage of favorable outcomes, 69.2%. There were no complications such as CNS infection or hemorrhage in this study.

CONCLUSION

A subdural transducer-tipped catheter (CMS) can be used as the first-line equipment for monitoring ICP in patients with severe head injury. The clinical results are similar with other recent studies, but no complication such as infection or hemorrhage occurred in this study.

Outcomes of Blunt Head Trauma without Intracranial Pressure Monitoring

Although guidelines exist for intracranial pressure (ICP)-guided treatment after head trauma, no conclusive data exist that support routine ICP monitoring. A retrospective case series was reviewed of all patients admitted to the intensive care unit with a diagnosis of blunt head trauma between January 1, 1999 and December 31, 2004. None of the patients in the final analysis had ICP monitoring. Data collected included age, sex, mechanism of injury, Glasgow Coma Score (GCS) at admission, injury severity score, disposition, and length of stay. One hundred thirty-one patients with a median age of 41 years were included. There were 104 men (79%). The median GCS at admission was 12. There were 22 deaths (17% mortality). Stepwise logistic regression analysis identified older age, higher injury severity score, and lower GCS to be predictors of death. The mortality rate was higher in patients with GCS ≤8 compared with GCS >8 (33% vs 8%, respectively; P < 0.001). Ten of 23 patients with a GCS of 3 died (43% mortality). The median time to death for patients with a GCS of 3 was 2 days. Although the Brain Trauma Foundation has published guidelines advocating routine ICP monitoring, no large randomized prospective studies are available to determine its effect on outcome. None of the patients in this study had ICP monitoring. Our overall survival rate of 83 per cent is relatively high. Patients with a low GCS and, specifically, those with a GCS of 3 may not benefit from ICP monitoring because of early and irreversible trauma. Variability in the use of ICP monitoring will remain until ICP monitoring can be conclusively proven to improve outcome.

Timing of Surgery After Multisystem Injury With Traumatic Brain Injury: Effect on Neuropsychological and Functional Outcome

OBJECTIVE

The optimal timing for noncranial surgery after multisystem injury is not known. Early surgery may lead to decreased pulmonary complications and length of stay, but also predispose to secondary brain injury if decreased cerebral perfusion occurs intraoperatively. Previous work has not consistently evaluated neuropsychological or functional outcome. We sought to determine whether 6-month neuropsychological and functional outcome was associated with timing of noncranial surgery after traumatic brain injury.

MATERIALS

We performed a cohort study to evaluate the effect of timing of non-neurosurgical operative interventions on neuropsychological and functional outcome, morbidity, and mortality. Early surgery was defined as <or=24 hours after injury, and late surgery, >24 hours after injury but during the same admission. Patients with a nonoperative brain injury and an operative facial or orthopedic fracture were selected from two randomized trials previously performed at our Level I trauma center. Data were abstracted from medical records and outcome had been prospectively gathered as part of the two clinical trials.

RESULTS

Patients undergoing early or late surgery had similar demographics, overall injury severity, traumatic brain injury severity, and admission characteristics. The early group had more open orthopedic fractures, but also underwent multiple operations more often than did the late group. At 6 months postinjury, patients in the early group had a better composite neuropsychological score than did those in the late group on unadjusted analysis and after including a propensity score. After adjusting for potential confounders, this difference was significant. No significant differences in return to work or Glasgow Outcome Score were noted. The late group had a higher incidence of pneumonia and a longer hospital stay (p<0.10).

CONCLUSIONS

In traumatic brain injury patients with multisystem trauma, early timing of orthopedic and facial fracture fixation under general anesthesia was not associated with worse neuropsychological or functional outcome when compared with the outcomes associated with late surgery. Clinical conclusions may be limited by inherent selection bias and unmeasured confounding. However, these results contribute to equipoise regarding timing of surgery after multiple injuries, and emphasize the need for a randomized trial.

Current experiences in the use of the severe head-injury guidelines in Taiwan

BACKGROUND

Head injury is the leading cause of death and disability for patients who experienced a major accident. It has been suggested that a well-planned neurointensive care management can effectively reduce the secondary brain insults. The BTF and the AANS proposed the Guidelines for the Management of Severe Head Injury in 1995. The purpose of this study was to obtain a consensus on whether the guidelines are suitable for treating patients with severe head injury in Taiwan.

METHODS

Data from patients with severe head injury were collected from 6 different medical centers in Taiwan. The methods for controlling ICP, CPP, and hyperventilation, and the medical treatment with vasopressors and sedatives have been analyzed.

RESULTS

Ninety-four patients with severe head injury (GCS <or= 8) were included in the study. The male-to-female ratio was 2.9:1. Mean age was 43.9 +/- 21.8 years. The GOS score for those patients with ICP higher than 20 mm Hg that resulted in poor outcome was approximately 2.91 times (P<.05) higher than that of patients with ICP lower than 20 mm Hg.

CONCLUSIONS

The most beneficial feature of the guidelines was the close control of ICP with an ICP monitor. Patients who received prophylactic sedatives had a favorable outcome (odds ratio, 2.8; CI, 1.0-7.5). There were no significant statistical differences between patients with and those without application of hyperventilation for maintenance of CPP.

Simvastatin and atorvastatin improve behavioral outcome, reduce hippocampal degeneration, and improve cerebral blood flow after experimental traumatic brain injury

The treatment of traumatic brain injury (TBI) remains limited, and aside from surgical hematoma evacuation, clinical management is largely supportive and directed toward management of cerebral edema and intracranial hypertension. Secondary neuronal injury caused by ischemia and the development of cerebral edema may occur in the subacute phase, with intracranial pressures often peaking in the first several days following injury. Because inflammation contributes significantly to the pathophysiology of cerebral ischemia and endothelial dysfunction underlies the development of cerebral edema, therapeutic strategies that target the post-traumatic inflammatory cascade and reduce endothelial dysfunction hold enormous potential to improve clinical outcomes after TBI. Statins inhibit inflammation by suppressing inflammatory cytokine release, and by interfering with multiple steps of leukocyte recruitment and migration into the CNS. In this study, we demonstrate that treatment with atorvastatin and simvastatin markedly reduced functional neurological deficits after traumatic brain injury in mice. These effects were accompanied by histological reduction in degenerating hippocampal neurons and suppression of inflammatory cytokine mRNA expression in brain parenchyma. Furthermore, statin treatment improved cerebral hemodynamics following head injury. Thus, the administration of statins may represent a viable therapeutic strategy in the acute treatment of closed head injury.

The role of surgery in traumatic brain injury

PURPOSE OF REVIEW

To identify the surgical indications in the treatment of posttraumatic intracranial hematomas and to evaluate the role of external decompression in severe posttraumatic intracranial hypertension.

RECENT FINDINGS

An evidence-based review resulted recently in the publication of Guidelines for Surgical Management of Traumatic Brain Injury. Unfortunately all published surgical studies are at the level of simple options with no standards. We know that a number of patients harbouring small epidural/subdural hematomas can be managed conservatively when the lesions are less than 10 mm of thickness and with a midline shift of less than 5 mm. With exception of these few cases, the current practice is that a large number of patients with posttraumatic hematomas are operated either within 24 h from injury (with acute subdural hematomas as the prevailing lesion) or later (with parenchymal hematomas as the prevailing lesion). According to a recent European study, about one third of these patients are also decompressed.

SUMMARY

A surgical approach is frequent in posttraumatic intracranial hematomas in spite of a low level of evidence. One of the surgical options either in association with hematoma evacuation or in isolation is the technique of bone flap decompression.

Brief review: Practice variation in end of life care in the ICU: implications for patients with severe brain injury

PURPOSE

To review end of life care issues in the intensive care unit (ICU) and how practice variation might affect the ultimate outcome of acute brain injury.

SOURCES

Bibliographic literature search and personal files.

FINDINGS

In Canada, 10-20% of critically ill adults die in the ICU. Many of these deaths follow acute brain injury in the setting of clinical deterioration, life support limitation and brain death. This brief review addresses some key elements of end of life care for critically ill brain injured patients, including family interactions, making survival predictions, and factors influencing decision-making about cardiopulmonary resuscitation and withdrawal of mechanical ventilation.

CONCLUSIONS

Provision of compassionate high quality end of life care should be standard of practice for brain injured and all other critically ill patients who cannot survive. Inconsistencies in end of life care may affect where, when and how patients die, the quality of their death and whether or not they are considered for organ and tissue donation.

Clinical trials in pediatric traumatic brain injury: unique challenges and potential responses

In order to optimize pediatric traumatic brain injury translational and clinical research, scientific and ethical challenges need to be recognized and addressed. Having recently conducted a multisite phase II safety/feasibility trial of magnesium sulfate as a neuroprotective agent, we supplement our own experience by a mini review of similar studies, identifying challenges and possible responses from the perspective of families, investigators, funding agencies and society.

Effect of pre-hospital advanced life support with rapid sequence intubation on outcome of severe traumatic brain injury

BACKGROUND

The role of pre-hospital trauma care and the effect of pre-hospital rapid sequence intubation (RSI) on patient outcome are still not clear. This study evaluated the impact of pre-hospital trauma care by emergency physicians (EP) on mortality from severe traumatic brain injury (TBI) and a 180-day Glasgow Outcome Scale (GOS).

METHODS

A 48-month parallel non-controlled cohort study compared a group of 64 patients with severe TBI [Glasgow Coma Scale (GCS) < 9; Injury Severity Score (ISS) > 15] who received pre-hospital advanced life support (ALS) with RSI and were transported to the hospital by EPs (EP group), with a group of 60 patients who did not receive pre-hospital ALS with RSI [emergency medical technicians (EMT) group].

RESULTS

There were no significant statistical differences between the groups in age (P= 0.79), mechanism of injury (P= 0.68), gender (P= 0.82), initial GCS (P= 0.63), initial SaO(2) in the field (P= 0.63), initial systolic blood pressure in the field (P= 0.47) and on-scene time (P= 0.41). In the EP group, there was significantly better first hour survival (97% vs. 79%, P= 0.02), first day survival (90% vs. 72%, P= 0.02), better functional outcome (GOS 4-5: 53% vs. 33%, P < 0.01; GOS 2-3: 8% vs. 20%, P < 0.01) and shortened hospitalization time in intensive care unit (ICU) (P= 0.03) and other departments (P= 0.04). In total hospital mortality, we detected no differences between both groups [EP group: 40% (95% CI: 34-45%) vs. EMT group 42% (95% CI: 36-47%, P= 0.76], except in a subgroup of patients with GCS 6-8 where there was significantly lower total hospital mortality in the EP group (24% vs. 78%, P < 0.01).

CONCLUSION

After starting the trauma care system with emergency physicians in our region, there was a decrease in the number of deaths on hospital admission, a reduction in hospital mortality in the GCS group 6-8, a change in the temporal distribution of deaths, an improvement in functional neurological outcome and shortened hospitalization time.

Retrospective evaluation of anemia and transfusion in traumatic brain injury

BACKGROUND

Despite clear evidence in critical care that blood transfusion has an adverse impact on outcome, neurosurgical textbooks still recommend transfusion of patients with traumatic brain injury (TBI) to a hematocrit (HCT) of 30%. There is little empirical evidence to support this practice. The current study addresses transfusion requirements in TBI in terms of neurologic outcome.

METHODS

Retrospective record review of patients with severe TBI. Outcome measures were Glasgow Coma Scale score (GCS), Glasgow Outcome Score (GOS), and Ranchos Los Amigos Score (RLA) at hospital discharge (D/C); and GOS and Functional Independence Measures at follow-up. Association of outcomes with the number of days the HCT <30% and lowest measured HCT were evaluated.

RESULTS

In all, 169 patients reviewed; 150 with D/C outcome data and 72 with long-term follow-up data. Univariate analysis showed that lowest measured HCT was associated with lower D/C GCS, D/C GOS, and RLA scores. Linear regression showed that more days with HCT <30% were associated with improved neurologic outcomes measured by GOS (R2 = 0.424, p < 0.001), GCS (R2 = 0.381, p < 0.001) and RLA (R2 = 0.392, p < 0.001) scores on D/C. Both transfusion and lowest measured HCT were significantly associated with all lower outcome scores on D/C. Additional factors with adverse impact on outcome were head Abbreviated Injury Score (AIS), Injury Severity Score, hyperglycemia, and hypotension. Long-term outcomes were only significantly associated with head AIS.

CONCLUSIONS

Patients with severe TBI should not have a different transfusion threshold than other critical care patients. Prospective studies are needed to evaluate the effects of anemia in TBI.

Intensive care unit management of the trauma patient

OBJECTIVE

The goal of this concise review is to provide an overview of some of the most important intensive care unit issues and approaches that are unique to trauma patients as compared with the general intensive care unit population.

STUDY SELECTION

Clinical trials in trauma patients focusing on hemorrhage control, issues in resuscitation, staged operative repair of multiple injuries, the diagnosis and therapy of the abdominal compartment syndrome, and the treatment of traumatic brain injury were identified on PubMed.

CONCLUSIONS

The intensive care unit care of the trauma patient differs from that of other intensive care unit patients in many ways, one of the most important being the need to continuously integrate operative and nonoperative therapy. Although progress in the care of the injured has been made, death due to uncontrolled bleeding, severe head injury, or the development of multiple organ dysfunction syndrome remains all too common in this patient population. Furthermore, due to the potential nature of the injuries, the conundrum not infrequently arises that the optimal treatment for one injury or organ system, such as preoperative permissive hypotension in actively bleeding patients, may result in suboptimal or even deleterious therapy in the presence of another injury, such as traumatic brain injury.

LEARNING OBJECTIVES

On completion of this article, the reader should be able to:Dr. Deitch has disclosed that he is/was the recipient of grant/research funds from Celgene. Dr. Dayal has disclosed that she has no financial relationships with or interests in any commercial companies pertaining to this educational activity. Lippincott CME Institute, Inc., has identified and resolved all faculty conflicts of interest regarding this educational activity. Visit the Critical Care Medicine Web site (www.ccmjournal.org) for information on obtaining continuing medical education credit.

Outcome in neurocritical care: Advances in monitoring and treatment and effect of a specialized neurocritical care team

OBJECTIVE

To review current advances in the treatment of critically ill neurologic patients, including specialized care by neurointensivists.

DESIGN

Review article.

MAIN DISCUSSION AND CONCLUSIONS

Significant developments in the fields of neurology and neurosurgery have led to improved treatments for the critically ill neurologic patient. The major areas reviewed include neuromonitoring, disease-specific treatments, and specialized neurocritical care units and team. The current trend is for the application of the so-called multimodality neuromonitoring, which includes the use of several monitoring techniques, including intracranial pressure, brain electrophysiology, brain metabolism and oxygenation, and cerebral blood flow, among others. Many new therapies that have been introduced are discussed, including thrombolytic therapy for acute ischemic stroke, induced hypothermia for comatose survivors of cardiac arrest, and endovascular coiling for ruptured cerebral aneurysms. Lastly, the introduction of neurointensivists and neurocritical care units has been associated with reduced hospital mortality and resource utilization without changes in readmission rates or long-term mortality rates.

Intracranial pressure complicating severe traumatic brain injury in children: monitoring and management

OBJECTIVE

To identify factors associated with the use of intracranial pressure (ICP) monitoring and to establish which ICP-targetted therapies are being used in children with severe traumatic brain injury (TBI) in the United Kingdom. To evaluate current practice against recently published guidelines.

DESIGN AND SETTING

Prospective data collection of clinical and demographic information from paediatric and adult intensive care units in the UK and Ireland admitting children (< 16 years) with TBI between February 2001 and August 2003.

RESULTS

Detailed clinical information was obtained for 501 children, with information on the use of ICP monitoring available in 445. ICP monitoring was used in only 59% (75/127) of children presenting with an emergency room Glasgow Coma Scale of 8 or below. Large between centre variation was seen in the use of ICP monitoring, independent of severity of injury. There were 86 children who received ICP-targetted therapies without ICP monitoring. Wide between centre variation was found in the use of ICP-targetted therapies and in general aspects of management, such as fluid restriction, the use of muscle relaxants and prophylactic anticonvulsants. Intra-ventricular catheters are rarely placed (6% of cases); therefore cerebrospinal fluid drainage is seldom used as a first-line therapy for raised ICP. Jugular venous bulb oximetry (4%), brain microdialysis (< 1%) and brain tissue oxygen monitoring (< 1%) are rarely used in current practice. Contrary to published guidelines, moderate to severe hyperventilation is being used without monitoring for cerebral ischaemia.

CONCLUSIONS

There is an urgent need for greater standardisation of practice across UK centres admitting children with severe TBI.

Intracranial pressure monitoring: why monitor?

Evidence suggests that the mortality and morbidity of acquired brain injury could be reduced if clinicians used an aggressive intracranial pressure guided approach to care. Despite nearly 50 years of evidence that intracranial pressure monitoring benefits patient care, only about half of the patients who could benefit are monitored. Some clinicians express concerns regarding risks such as bleeding, infections, and inaccuracy of the technology. Others cite cost as the reason. This article discusses the risks and benefits of intracranial pressure monitoring and the current state of evidence of why patients should be monitored.

Case mix, outcomes and comparison of risk prediction models for admissions to adult, general and specialist critical care units for head injury: a secondary analysis of the ICNARC Case Mix Programme Database

INTRODUCTION

This report describes the case mix and outcome (mortality, intensive care unit (ICU) and hospital length of stay) for admissions to ICU for head injury and evaluates the predictive ability of five risk adjustment models.

METHODS

A secondary analysis was conducted of data from the Intensive Care National Audit and Research Centre (ICNARC) Case Mix Programme, a high quality clinical database, of 374,594 admissions to 171 adult critical care units across England, Wales and Northern Ireland from 1995 to 2005. The discrimination and calibration of five risk prediction models, SAPS II, MPM II, APACHE II and III and the ICNARC model plus raw Glasgow Coma Score (GCS) were compared.

RESULTS

There were 11,021 admissions following traumatic brain injury identified (3% of all database admissions). Mortality in ICU was 23.5% and in-hospital was 33.5%. Median ICU and hospital lengths of stay were 3.2 and 24 days, respectively, for survivors and 1.6 and 3 days, respectively, for non-survivors. The ICNARC model, SAPS II and MPM II discriminated best between survivors and non-survivors and were better calibrated than raw GCS, APACHE II and III in 5,393 patients eligible for all models.

CONCLUSION

Traumatic brain injury requiring intensive care has a high mortality rate. Non-survivors have a short length of ICU and hospital stay. APACHE II and III have poorer calibration and discrimination than SAPS II, MPM II and the ICNARC model in traumatic brain injury; however, no model had perfect calibration.

Effect of intracranial pressure monitoring and targeted intensive care on functional outcome after severe head injury*

OBJECTIVE

: Intracranial hypertension after severe head injury is associated with case fatality, but there is no sound evidence that monitoring of intracranial pressure (ICP) and targeted management of cerebral perfusion pressure (CPP) improve outcome, despite widespread recommendation by experts in the field. The purpose was to determine the effect of ICP/CPP-targeted intensive care on functional outcome and therapy intensity levels after severe head injury.

DESIGN

: Retrospective cohort study with prospective assessment of outcome.

SETTING

: Two level I trauma centers in The Netherlands from 1996 to 2001.

PATIENTS

: Three hundred thirty-three patients who had survived and remained comatose for >24 hrs, from a total of 685 consecutive severely head-injured adults.

INTERVENTIONS

: In center A (supportive intensive care), mean arterial pressure was maintained at approximately 90 mm Hg, and therapeutic interventions were based on clinical observations and computed tomography findings. In center B (ICP/CPP-targeted intensive care), management was aimed at maintaining ICP <20 mm Hg and CPP >70 mm Hg. Allocation to either trauma center was solely based on the site of the accident.

MEASUREMENTS AND MAIN RESULTS

: We measured extended Glasgow Outcome Scale after >/=12 months. Patient characteristics were well balanced between the centers. ICP monitoring was used in zero of 122 (0%) and 142 of 211 (67%) patients in centers A and B, respectively. In-hospital mortality rate was 41 (34%) vs. 69 (33%; p = .87). The odds ratio for a more favorable functional outcome following ICP/CPP-targeted therapy was 0.95 (95% confidence interval, 0.62-1.44). This result remained after adjustment for potential confounders. Sedatives, vasopressors, mannitol, and barbiturates were much more frequently used in center B (all p < .01). The median number of days on ventilator support in survivors was 5 (25th-75th percentile, 2-9) in center A vs. 12 (7-19) in center B (p < .001).

CONCLUSIONS

: ICP/CPP-targeted intensive care results in prolonged mechanical ventilation and increased levels of therapy intensity, without evidence for improved outcome in patients who survive beyond 24 hrs following severe head injury.

Hospitalizations for critically ill children with traumatic brain injuries: A longitudinal analysis*

OBJECTIVE

This study examines the incidence, utilization of procedures, and outcomes for critically ill children hospitalized with traumatic brain injury over the period 1988-1999 to describe the benefits of improved treatment.

DESIGN

Retrospective analysis of hospital discharges was conducted using data from the Health Care Cost and Utilization Project Nationwide Inpatient Sample that approximates a 20% sample of U.S. acute care hospitals.

SETTING

Hospital inpatient stays from all types of U.S. community hospitals.

PARTICIPANTS

The study sample included all children aged 0-21 with a primary or secondary ICD-9-CM diagnosis code for traumatic brain injury and a procedure code for either endotracheal intubation or mechanical ventilation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Deaths occurring during hospitalization were used to calculate mortality rates. Use of intracranial pressure monitoring and surgical openings of the skull were investigated as markers for the aggressiveness of treatment. Patients were further classified by insurance status, household income, and hospital characteristics. Over the 12-yr study period, mortality rates decreased 8 percentage points whereas utilization of intracranial pressure monitoring increased by 11 percentage points. The trend toward more aggressive management of traumatic brain injury corresponded with improved hospital outcomes over time. Lack of insurance was associated with vastly worse outcomes. An estimated 6,437 children survived their traumatic brain injury hospitalization because of improved treatment, and 1,418 children died because of increased mortality risk associated with being uninsured. Improved treatment was valued at approximately dollar 17 billion, whereas acute care hospitalization costs increased by dollar 1.5 billion (in constant 2000 dollars). Increased mortality in uninsured children was associated with a dollar 3.76 billion loss in economic benefits.

CONCLUSIONS

More aggressive management of pediatric traumatic brain injury appears to have contributed to reduced mortality rates over time and saved thousands of lives. Additional lives could be saved if mortality rates could be equalized between insured and uninsured children.

Efficiency of 7.2% hypertonic saline hydroxyethyl starch 200/0.5 versus mannitol 15% in the treatment of increased intracranial pressure in neurosurgical patients - a randomized clinical trial [ISRCTN62699180]

Introduction

This prospective randomized clinical study investigated the efficacy and safety of 7.2% hypertonic saline hydroxyethyl starch 200/0.5 (7.2% NaCl/HES 200/0.5) in comparison with 15% mannitol in the treatment of increased intracranial pressure (ICP).

Methods

Forty neurosurgical patients at risk of increased ICP were randomized to receive either 7.2% NaCl/HES 200/0.5 or 15% mannitol at a defined infusion rate, which was stopped when ICP was < 15 mmHg.

Results

Of the 40 patients, 17 patients received 7.2% NaCl/HES 200/0.5 and 15 received mannitol 15%. In eight patients, ICP did not exceed 20 mmHg so treatment was not necessary. Both drugs decreased ICP below 15 mmHg (p < 0.0001); 7.2% NaCl/HES 200/0.5 within 6.0 (1.2–15.0) min (all results are presented as median (minimum-maximum range)) and mannitol within 8.7 (4.2–19.9) min (p < 0.0002). 7.2% NaCl/HES 200/0.5 caused a greater decrease in ICP than mannitol (57% vs 48%; p < 0.01). The cerebral perfusion pressure was increased from 60 (39–78) mmHg to 72 (54–85) mmHg by infusion with 7.2% NaCl/HES 200/0.5 (p < 0.0001) and from 61 (47–71) mmHg to 70 (50–79) mmHg with mannitol (p < 0.0001). The mean arterial pressure was increased by 3.7% during the infusion of 7.2% NaCl/HES 200/0.5 but was not altered by mannitol. There were no clinically relevant effects on electrolyte concentrations and osmolarity in the blood. The mean effective dose to achieve an ICP below 15 mmHg was 1.4 (0.3–3.1) ml/kg for 7.2% NaCl/HES 200/0.5 and 1.8 (0.45–6.5) ml/kg for mannitol (p < 0.05).

Conclusion

7.2% NaCl/HES 200/0.5 is more effective than mannitol 15% in the treatment of increased ICP. A dose of 1.4 ml/kg of 7.2% NaCl/HES 200/0.5 can be recommended as effective and safe. The advantage of 7.2% NaCl/HES 200/0.5 might be explained by local osmotic effects, because there were no clinically relevant differences in hemodynamic clinical chemistry parameters.

Primer on medical management of severe brain injury

OBJECTIVE

To review the current understanding of the medical management of severe brain injury.

DATA SOURCE

The MEDLINE database, bibliographies of selected articles, and current English-language texts on the subject.

STUDY SELECTION

Studies related to management of intracranial hypertension, traumatic brain injury, and brain edema.

DATA EXTRACTION

All studies relevant to the subject under consideration were considered, with a focus on clinical studies in adults.

DATA SYNTHESIS

Basic rules of resuscitation must apply, including adequate ventilation, appropriate fluid administration, and cardiovascular support. The control of intracranial pressure can be considered in three steps. The first step should be initial slight hyperventilation with a target PaCO2 of 35 mm Hg and cerebrospinal fluid drainage for intracranial pressure of >15-20 mm Hg. The second step should be mannitol or hypertonic saline and hyperventilation to target PaCO2 of 28-35 mm Hg. The third step should be barbiturate coma or decompressive craniectomy. Additional management issues, including seizure prophylaxis, sedation, nutritional support, use of hypothermia, and corticosteroids, are also discussed.

CONCLUSIONS

Brain injury is frequently associated with the development of brain edema and the development of intracranial hypertension. However, with a coordinated, stepwise, and aggressive approach to management, focusing on control of intracranial pressure without adversely affecting cerebral perfusion pressure, outcomes can be good.

Variability in Trauma Center Outcomes for Patients With Moderate Intracranial Injury

BACKGROUND

The variability of outcome between Trauma Centers has not been extensively studied as a possible avenue for performance improvement. Trauma Center variability in severity-adjusted survival for patients with moderate intracranial injury (MII) was studied in order to determine the association of MII-related process of care variables with outcomes. The analytic results were supplemented with peer review of MII patients with unexpected outcomes and identified potential process of care variables.

METHODS

A retrospective cohort study was undertaken based on data submitted to a statewide trauma center database from July '95 through June '98. MII patients had one or more selected ICD-9-CM codes with an AIS-90 severity score of 3 or 4 but no higher. Severity adjustment was done using case matching and a logistic function based New Model that appropriately accounts for patients intubated on Emergency Department arrival. MII-related process of care variables derived from the database were identified and their relationship with outcome were evaluated individually and using multivariate methods. Trauma center personnel conducted standardized peer reviews.

RESULTS

The study included data from 6765 patients treated at 26 trauma centers. Two centers (2PZW) had significantly more survivors than expected by both severity adjustment methods. Three had significantly fewer survivors than expected (3NZW). By several measures, patients treated in the 2PZW centers were more seriously injured and older than those in the 3NZW centers. CT of the head performed in the treating hospital was the only process of care variable associated with outcome in multivariate evaluations. Peer review also found little association between process of care variables and patient outcomes. However, peer review reported that 23.7% of unexpected deaths identified by case matching or the New Model were preventable or potentially preventable. Peer review also identified as medically unnecessary significant percentages of patients with unexpectedly long stays in hospital (26.4%) or in ICU (17.3%) identified by case matching. Nearly 45% of unexpected complications were judged preventable or potentially preventable.

CONCLUSIONS

Two severity adjustment methods identified significant variability in trauma center outcomes for patients with MII. The difference in outcomes between the centers with better than expected (2PZW) and poorer than expected outcomes (3NZW) was substantial. Peer review identified significant opportunities for reducing unexpected deaths, stays in hospital and in ICU, and the occurrence of complications. Trauma registry data and peer reviews found little relationship between available process of care variables and patient outcomes. This study should stimulate discussions to understand reasons for outcome variability and ways to reduce it.

Traumatic brain injury and stabilisation of long bone fractures: an update

In the era of "damage control orthopaedics", the timing and type of stabilisation of long bone fractures in patients with associated severe traumatic brain injury has been a topic of lively debate. This review summarises the current evidence available regarding the management of these patients. There appear to be no clear treatment guidelines. Irrespective of the treatment protocol followed, if secondary brain damage is to be avoided at all times, ICP monitoring should be used, both in the intensive care unit and in the operating theatre during surgical procedures, since aggressive ICP management appears to be related to improved outcomes. Treatment protocols should be based on the individual clinical assessment, rather than mandatory time policies for fixation of long bone fractures.

Therapeutic hypertension: principles and methods

The aspects of cardiovascular physiology important for the safe and effective implementation and titration of hypertensive therapy among neurosurgical patients with neurological or neurosurgical illness/injury are reviewed. Therapeutic hypertension may be an appropriate treatment for some neurological or neurosurgical conditions, e.g., vasospasm or support of cerebral perfusion pressure. Initiation and maintenance of hypertension should be done safely to avoid complications and/or undesired side effects. Accurate measurement of the arterial and central vascular pressures, the limitations of those methods, and alternative estimates of intravascular volume are reviewed. Hypertensive therapy is accomplished by modifying cardiac output and systemic vascular resistance, the principal physiological determinants of blood pressure. The goals of hypertensive therapy can be achieved by proper evaluation and manipulation of the four components of cardiac output, preload, afterload, heart rate and contractility. Measurement or calculation of estimates of these parameters is important in the selection of proper medications or supplemental fluid administration.

Initial head computed tomographic scan characteristics have a linear relationship with initial intracranial pressure after trauma

BACKGROUND

Despite current recommendations by the Brain Trauma Foundation regarding the placement of intracranial pressure (ICP) monitoring devices, advances in computed tomographic (CT) scan technology have led to the suggestion that increased ICP may be predicted by findings on admission head CT scan and that patients without such findings do not require such monitoring. A linear relationship exists between characteristics of admission head CT scan and initial ICP level, allowing for selective placement of ICP monitoring devices.

METHODS

From 1997 to 2001, a retrospective review of patients admitted with a Glasgow Coma Scale (GCS) score < 8 and head CT scan who underwent ventriculostomy placement at our institution, was conducted. Patients undergoing craniotomy with evacuation of mass lesions before ventriculostomy placement were excluded. Age, sex, mechanism of injury, anoxia, osmotic treatment, presence of drugs/alcohol, initial mean arterial pressure, initial GCS score, and initial ICP were recorded. Initial head CT scans were reviewed independently by two neuroradiologists who were blinded to ICP measurements, neurosurgical treatment, patient outcome, and each other's interpretation. Initial CT scans were evaluated and scored on a 1 (normal) to 3 (abnormal) scale with respect to ventricle size, basilar cistern size, sulci size, degree of transfalcine herniation, and gray/white matter differentiation. Initial ICP readings and CT scan findings were compared to determine whether a significant linear relationship existed between the above CT scan findings and ICPs. Logistic and univariate linear regression were used to compare averaged radiologist score versus dichotomized ICP at baseline.

RESULTS

Initial head CT scan characteristics show a linear relationship to baseline ICPs. These findings are associative, but are not uniformly predictive.

CONCLUSION

Therefore, the current Brain Trauma Foundation recommendation of ICP monitoring in those patients presenting with a GCS score < 8 with an abnormal CT scan or a normal CT scan with age > 40 years, systolic blood pressure < 90 mm Hg, or exhibiting posturing should be followed.

Cerebral pathophysiology and critical care neurology: basic hemodynamic principles, cerebral perfusion, and intracranial pressure

Pediatric neurologic intensive care differs from standard pediatric intensive care in two important respects. First, the diagnosis, monitoring, and management of problems related to disorders of cerebral perfusion and intracranial pressure (ICP) are central to nearly all of pediatric neurologic and neurosurgical intensive care. Second, various clinical problems normally encountered in the intensive care unit (ICU) have additional implications when associated with neurologic disease. Regardless of the cause, treatment should be undertaken as expeditiously as possible and should be based on the principles of resuscitation, reducing the volume of the intracranial contents, and reassessment. This chapter aims to outline some basic principles underlying the diagnosis and management of elevated ICP in children.

[Medical prehospital rescue in head injury]

OBJECTIVE

To evaluate the effectiveness of prehospital medical care in head-injured patients.

PATIENTS AND METHODS

All head-injured patients admitted in Bicêtre hospital from 1995 to 1999 were retrospectively studied. Glasgow Coma Scale (GCS) score, mean arterial pressure (MAP) and SpO(2) measured on the field were compared to GCS, MAP and SpO(2) on arrival in the hospital. All treatments given during transport and first data recorded in the hospital were noted. Each parameter was compared to outcome at 6 months. Then, significant parameters were compared with a multivariate analysis.

RESULTS

Three hundred and four patients were included, 80% had a GCS <or= 8 and 45% a GCS = 3. At 6 months, 43% of the patients had no or mild sequelae and 45% died. Prehospital time was 2 h 55 min +/- 1 h 40 min. During transport, 75% of hypoxemic events were corrected, but GCS and MAP decreased significantly. None of the patients with non-reactive mydriasis received any osmotherapy and all patients with non-reactive mydriasis until hospital admission died (n = 55). After multivariate analysis, parameters significantly related to outcome were, on the field, MAP (p < 0.025) and at hospital SAPS II (p < 0,001), GCS (p < 0.001), non-reactive mydriasis (p < 0.025), hyperglycemia (p < 0.025) and low haemoglobinemia (p < 0.001).

CONCLUSION

Respect of guidelines is important to improve medical care. Prehospital management corrected hypoxemia but not hypotension. The lack of osmotherapy after mydriasis cannot be explained and is probably an error. Patient route must be simplified to decrease time delay from field to hospital. Improvement in prehospital care may decrease mortality in head-injured patients.

Prehospital Endotracheal Intubation for Trauma Does Not Improve Survival over Bag-Valve-Mask Ventilation

BACKGROUND

Few data exist supporting a survival benefit to prehospital endotracheal intubation (ETI) over bag-valve-mask ventilation (BVM) in trauma patients.

METHODS

Data were reviewed from all trauma patients transported to our Level I trauma center receiving prehospital ETI or BVM. Mortality was adjusted by age, Revised Trauma Score, Injury Severity Score, and mechanism of injury (penetrating vs. blunt).

RESULTS

Of 5,773 patients, 316 (5.5%) had ETI and 217 (3.8%) had BVM. Patients receiving ETI were significantly more like to die (88.9% vs. 30.9%, p < 0.0001). When corrected for Injury Severity Score, Revised Trauma Score, and mechanism of injury, ETI was associated with similar or greater mortality than BVM. ETI patients had longer prehospital times (22.0 vs. 20.1 minutes, p = 0.0241).

CONCLUSION

In our trauma system, when corrected for mechanism and severity of anatomic and physiologic injury, ETI confers no survival advantage over BVM and slightly increases prehospital time.

Management of brain and spine injuries

For both SCI and TBI, physicians are unable to affect reversal of the cellular injuries suffered at the time of trauma directly. Unfortunately, understanding such processes is just on the horizon. Physicians do, however, have significant influence on recovery through the avoidance of secondary insults to the injured nervous system. In keeping with trauma in general, the mechanism for this is focused and coordinated multi-disciplinary care originating at the earliest contact and continuing through acute care. Aggressive and pre-emptive attention to the ABC(D)s with attention to the needs of the injured nervous system, appropriate monitoring in all patients, meticulous medical management, and prompt surgical intervention when indicated have made marked improvements in outcome, particularly in TBI. Focusing on the basics and strict attention to detail appear to be the major roles played in the care of CNS trauma.

Fractures in access to and assessment of trauma systems

BACKGROUND

Trauma is a major public health problem and organized systems of trauma care have been shown to substantially reduce trauma-related mortality. Currently California and many other states have incompletely developed systems of trauma care delivery. This study was undertaken to determine how frequently patients incurring serious trauma in California receive treatment at a trauma center.

STUDY DESIGN

Hospital discharge records for 360,743 acute trauma patients for 1995 to 1997 were analyzed. Abbreviated Injury Scale scores were calculated from discharge diagnosis codes. Severity of trauma and the need for trauma center treatment was defined by eight Abbreviated Injury Scale criteria combined with patient age and type of injury.

RESULTS

According to study criteria, 67,718 patients needed trauma center care and 56% were treated at a trauma center. Among patients less than 55 years of age, 62% were treated at a trauma center compared with 40% of those aged 55 years or more (p < 0.0001). For patients less than 55 years old with brain injuries, 66% were treated at a trauma center compared with 44% for patients aged 55 years or more (p < 0.0001). Of the 29,849 patients who met Abbreviated Injury Scale criteria but were not treated at trauma centers, 59% were in counties with designated trauma centers and 41% were in counties without trauma centers.

CONCLUSIONS

Only 56% of seriously injured patients in California were treated at trauma centers, despite most of the injuries occurring in the catchment areas of designated trauma care systems. Substantial undertriage of serious trauma patients to trauma centers appears to be occurring, especially in older persons and in persons with brain injuries. Efforts to understand why undertriage is occurring so frequently are hampered by fragmentation of the systems of care, inadequate data management systems, and lack of trauma care performance reporting by non-trauma center hospitals.

Intracranial pressure following aneurysmal subarachnoid hemorrhage: monitoring practices and outcome data

OBJECT

Elevated intracranial pressure (ICP) is an important consequence of aneurysmal subarachnoid hemorrhage (SAH) that often results in decreased cerebral perfusion and secondary clinical decline. No definitive guidelines exist regarding methods and techniques for ICP management following aneurysm rupture. The authors describe monitoring practices and outcome data in 621 patients with aneurysmal SAH admitted to their neurological intensive care unit during an 8-year period (1996-2003).

METHODS

A fiberoptic catheter tip probe or external ventricular drain (EVD) was used to record ICP values. The percentage of monitored patients varied, as expected, according to admission Hunt and Hess grade (p < 0.0001). Intracranial pressure monitoring devices were used in 27 (10%) of 264 Grade I to II patients, 72 (38%) of 189 Grade III patients, and 134 (80%) of 168 Grade IV to V patients. There was a strong propensity to favor transduced ventricular drains over parenchymal fiberoptic bolts, with the former used in 221 (95%) of 233 cases. This tendency was particularly strong in the poor-grade cohort, in which EVDs were placed in 99% of monitored individuals. The rates of cerebrospinal fluid infection in patients in whom ICP probes (0%) and ventricular drains (12%) were placed accorded with those in the literature.

CONCLUSIONS

Following aneurysmal SAH, ICP monitoring prevalence and techniques differ with respect to admission Hunt and Hess grade and are associated with the patient's functional status at discharge.

New neurophysiology and central nervous system dysfunction

PURPOSE OF REVIEW

The goal of this article is to summarize very recent technologic advances in neurophysiologic monitoring and to illustrate their potential benefit to critical care medicine.

RECENT FINDINGS

Simplified, computer-processed electroencephalography devices now permit cost-effective, long-term critical care monitoring. They may be used alone to objectively assess sedation or coma level. In addition, these monitors serve as screening tools for more detailed electrophysiologic characterization of cortical dysfunction resulting from seizures, ischemia, or hypoxia. Somatosensory potentials broaden these capabilities to the entire neuraxis, whereas long-latency auditory evoked potentials facilitate measurement of changes in vigilance and cognition. Motor evoked potentials offer a sensitive and reliable method to determine the function of descending motor pathways in uncooperative or unresponsive patients. They may also yield a new measure of cortical excitability. New developments with transcranial Doppler ultrasonography promise noninvasive measures of cerebral perfusion pressure and particulate embolization. Near-infrared spectroscopy appears to enable noninvasive measurement of regional tissue oxygenation in both the brain and spinal cord.

SUMMARY

When used together, these continuous measures of synaptic function, cerebral perfusion, and oxygenation give the clinician a vast amount of otherwise unobtainable information regarding the functional status of the central nervous system.