Narrative review: tetanus-a health threat after natural disasters in developing countries

Tetanus is an expected complication when disasters strike in developing countries, where tetanus immunization coverage is often low or nonexistent. Collapsing structures and swirling debris inflict numerous crush injuries, fractures, and serious wounds. Clostridium tetani infects wounds contaminated with dirt, feces, or saliva and releases neurotoxins that may cause fatal disease. Clusters of infections have recently occurred after tsunamis and earthquakes in Indonesia, Kashmir, and Haiti. The emergency response to clusters of tetanus infections in developing countries after a natural disaster requires a multidisciplinary approach in the absence of an intensive care unit, readily available resources, and a functioning cold-chain system. It is essential that injured people receive immediate surgical and medical care of contaminated, open wounds with immunization and immunoglobulin therapy. Successful treatment of tetanus depends on prompt diagnosis of clinical tetanus, treatment to ensure neutralization of circulating toxin and elimination of C. tetani infection, control of spasms and convulsions, maintenance of the airway, and management of respiratory failure and autonomic dysfunction.

Intraventricular hemorrhage volume predicts poor outcomes but not delayed ischemic neurological deficits among patients with ruptured cerebral aneurysms

BACKGROUND

Intraventricular hemorrhage (IVH) predicts worse outcomes following aneurysmal subarachnoid hemorrhage (SAH). One potential mechanism is that IVH predisposes to the development of delayed ischemic neurological deficits (DINDs). No previous studies have evaluated the association between IVH volume (in milliliters) and subsequent development of DINDs or poor outcomes.

OBJECTIVE

To assess the association between the volume of IVH and the subsequent development of DINDs, delayed cerebral infarction, death, and poor neurological outcomes, specifically among patients with concomitant SAH and IVH.

METHODS

We performed a cohort study involving 152 consecutive patients with concomitant SAH and IVH. To determine volume of IVH, we used the IVH Score, shown to correlate well with computerized volumetric assessment. To determine the relative quantity of subarachnoid blood, we applied the SAH Sum Score. Multivariate logistic regression was used to adjust for potential confounders.

RESULTS

There was no significant association between IVH volume and the development of DINDs or delayed infarction. In contrast, patients with poor neurological outcomes had significantly larger baseline IVH volume (mean, 11.8 mL vs 3.8 mL, P = .001). In the multivariate analysis, IVH volume was an independent predictor of poor outcomes (OR per mL: 1.11 [1.04-1.18]). Patients in the highest quartile for IVH volume were far more likely to progress to poor outcome compared with those in the lowest quartile (OR 4.09 [1.32-12.65]). Interobserver agreement in the determination of IVH Score was moderate to good.

CONCLUSIONS

IVH volume is an independent predictor of poor neurological outcomes, even after adjusting for the amount of subarachnoid blood. The pathophysiology of this association does not appear to involve an increased risk of DINDs or delayed infarction. Measures aimed at accelerating IVH clearance, such as intraventricular thrombolysis, merit further evaluation.

Multifactor clinical score and outcome of mechanical ventilation weaning trials: Burns Wean Assessment Program

BACKGROUND

The Burns Wean Assessment Program is a 26-factor weaning assessment worksheet and scoring instrument used to reduce practice variability in the clinical management of patients receiving mechanical ventilation. The instrument has been tested in patients in a medical-surgical intensive care unit, but further testing in different populations of adult patients is needed.

OBJECTIVES

To determine the relationship between Burns Wean Assessment Program scores and outcomes of weaning trials in patients treated with mechanical ventilation for 3 or more days.

METHODS

For 5 years in 5 adult critical care units (surgical, medical, neurological, thoracic-cardiovascular, and coronary care), advanced practice nurses collected scores within 24 hours of a weaning attempt. All patients were managed similarly by using a multidisciplinary pathway, the Burns Wean Assessment Program checklist, protocols for weaning trials, and sedation guidelines.

RESULTS

Of 1889 weaning attempts, 1669 (88%) were successful, and 220 (12%) were unsuccessful. Weaning outcomes did not differ according to sex, but significantly more trials were successful in younger patients than in older patients (P = .002) and in patients in different units (P = .01). Regardless of unit, patients with Burns Wean Assessment Program scores greater than 50 were significantly more likely to be weaned successfully (P = .001) than were patients with lower scores.

CONCLUSIONS

Systematic tracking of the factors and scores on the Burns Wean Assessment Program may be helpful in care planning and management and in determining weaning potential.

Less common etiologies of status epilepticus

Status epilepticus is treated as a neurologic emergency and only later are the potential etiologies assessed. While sometimes the cause for status epilepticus is apparent (e.g., antiepileptic drug withdrawal), all too often it is not identified, even after extensive diagnostic testing has been performed. With emphasis on the less-common etiologies, this review will cover various probable and known causes of status epilepticus among adults, children, and those patients with refractory epilepsy.

Neurocritical care of patients with central nervous system infections

Bacterial meningitis and viral encephalitis are life-threatening infections with high mortality rates. Patients who survive these infections often remain permanently disabled. Potential neurologic complications requiring careful attention include impaired consciousness, elevated intracranial pressure, hydrocephalus, stroke, and seizures. Systemic complications are also common and are frequently the immediate cause of death. Critical care of these patients should focus not only on treatment of the underlying infection and its immediate complications but also on minimizing secondary brain injury. Given the increasing complexity of the diagnostic and therapeutic modalities available in managing central nervous system infections, the involvement of neurocritical care units and neurointensivists may be particularly helpful in improving outcomes.

Acute Brain Infarcts After Spontaneous Intracerebral Hemorrhage

Background and Purpose— We aimed to determine the prevalence of acute brain infarcts using diffusion-weighted imaging (DWI) in patients with spontaneous intracerebral hemorrhage (ICH).

Methods— We collected data on consecutive patients with spontaneous ICH admitted to our institution between August 1, 2006 and December 31, 2008 and in whom DWI was performed within 28 days of admission. Patients with hemorrhage attributable to trauma, tumor, aneurysm, vascular malformation, and hemorrhagic conversion of arterial or venous infarction were excluded. Restricted diffusion within, contiguous with, or immediately neighboring the hematoma or chronic infarcts was not considered abnormal. Using multivariable logistic regression, we evaluated potential predictors of DWI abnormality including clinical and radiographic characteristics and treatments. A probability value <0.05 was considered significant in the final model.

Results— Among 118 spontaneous ICH patients (mean 59.6 years, 47.5% male, and 31.4% white) who also underwent MRI, DWI abnormality was observed in 22.9%. The majority of infarcts were small (median volume 0.25 mL), subcortical (70.4%), and subclinical (88.9%). Factors independently associated with DWI abnormality were prior ischemic stroke ( P =0.002), MAP lowering by ≥40% ( P =0.004), and craniotomy for ICH evacuation ( P =0.001).

Conclusion— We found that acute brain infarction is relatively common after acute spontaneous ICH. Several factors, including aggressive blood pressure lowering, may be associated with acute ischemic infarcts after ICH. These preliminary findings require further prospective study.

Glucose Regulation in Acute Stroke Patients (GRASP) trial: a randomized pilot trial

BACKGROUND AND PURPOSE

Hyperglycemia is associated with worse outcome in patients with acute stroke.

METHODS

We conducted a prospective, randomized, multicenter, 3-arm trial (tight control [target 70 to 110 mg/dL], loose control [target 70 to 200 mg/dL], and control usual care [70 to 300 mg/dL]) to assess the feasibility and safety of 2 insulin infusion protocol targets in patients with acute ischemic stroke. The planned sample was 72 subjects.

RESULTS

A total of 74 subjects were enrolled. Seventy-two (97%) had data available for the primary analyses and 73 (99%) had 3-month clinical outcome data. Median age was 67 years, median National Institutes of Health Stroke Scale score was 8, median glucose was 163 mg/dL, and median time to randomization was 10.7 hours. Fifty-nine percent of patients were diabetic, 35% received thrombolysis, and 14% of subjects died within 3 months. The loose control and usual care groups had median glucose concentrations of 151 mg/dL. The tight control group had a median glucose concentration of 111 mg/dL. The loose control group spent 90% of the first 24 hours in target and the tight group 44% of time in target. There was only one symptomatic patient with hypoglycemia in the loose control group (4%) and zero in the tight control group. The overall rates of hypoglycemia (<55 mg/dL) were 4% in control, 4% in loose, and 30% in tight. Exploratory efficacy analysis was conducted.

CONCLUSIONS

Insulin infusion for patients with acute ischemic stroke is feasible and safe using the insulin infusion protocol in the Glucose Regulation in Acute Stroke Patients (GRASP) trial. Exploratory efficacy analysis supports further comparative study.

Historical aspects of critical care and the nervous system

The appropriate starting point for a history of neurocritical care is a matter of debate, and the organization of facts and conjectures about it must be somewhat arbitrary. Intensive care for neurosurgical patients dates back to the work of Walter Dandy at the Johns Hopkins Hospital in the 1930s; many consider his creation of a special unit for their postoperative care to be the first real ICU. The genesis of neurocritical care begins in prehistory, however. This article gives a predominantly North American history, with some brief forays into the rest of the world community of neurointensivists.

CLASSIFICATION OF CEREBRAL INFARCTION AFTER SUBARACHNOID HEMORRHAGE IMPACTS OUTCOME

OBJECTIVE

Cerebral infarction (CI) after subarachnoid hemorrhage (SAH) is well described, but there is no validated classification.

METHODS

We prospectively enrolled 119 consecutive patients with SAH. We recorded admission World Federation of Neurological Societies grade and Columbia computed tomographic scores. Vasospasm was defined as transcranial Doppler of greater than 120 cm/second or typical clinical symptoms. CI was defined by computed tomographic or magnetic resonance imaging scan, and the date of discovery was recorded. CI was classified by a previously published method (single versus multiple, cortical versus deep versus combined). Outcomes were assessed at 14 days or discharge with the National Institutes of Health Stroke Scale and modified Rankin Scale (mRS), and at 28 days and 3 months with the mRS.

RESULTS

Vasospasm was associated with a higher risk of CI (odds ratio, 2.6; 95% confidence interval, 1.3–5.6; P = 0.01). The median time to detection was 4.2 days (interquartile range, 1.6–7.6 days) after SAH onset. CI classification was associated with the National Institutes of Health Stroke Scale score at 14 days (P = 0.002) and intensive care unit length of stay (P = 0.001). CI location (cortical, deep, or combined) was associated with National Institutes of Health Stroke Scale and mRS score at 14 days, and mRS score at 28 days and 3 months (P ≤ 0.02 for all). In a multiple logistic regression model, CI classification, World Federation of Neurological Societies grade, aneurysm diameter, and age were all associated with mRS score at 28 days and 3 months (P ≤ 0.05). Combined cortical and deep CI was associated with less improvement and poor outcome.

CONCLUSION

CI classification predicts outcomes after SAH. Future reports of CI after SAH should include this or similar descriptive information.

Cardiac troponin I and acute lung injury after subarachnoid hemorrhage

INTRODUCTION

There are few predictors of acute lung injury (ALI) or the acute respiratory distress syndrome (ARDS) after subarachnoid hemorrhage (SAH). We hypothesized that cardiac troponin I, which is associated with cardiovascular morbidity, would also predict ALI.

METHODS

We prospectively enrolled 171 consecutive patients with SAH. Troponin was routinely measured on admission and the next day and subsequently if abnormal. We prospectively recorded the maximum troponin, in-hospital events, and clinical endpoints. ALI and ARDS were defined by standard criteria.

RESULTS

Acute lung injury was found in 10 patients (6%), ARDS in an additional 14 (8%), and pulmonary edema without lung injury in 9 (5%). Maximum troponin was different in patients without lung injury or pulmonary edema (0.03 [0.02-0.12] mcg/l), ALI (0.17 [0.04-1.4]), or ARDS (0.31 [0.9-1.8], P < 0.001). In ROC analysis, a cutoff of 0.04 mcg/l had 91% sensitivity and 42% specificity for ALI or ARDS (AUC = 0.75, P < 0.001). Troponin was associated with ALI or ARDS after accounting for neurologic grade in multivariate models without further contribution from pneumonia, packed red cell transfusion, gender, tobacco use, coronary artery disease, vasospasm, depressed ejection fraction on echocardiography, or CT grade. Lung injury was associated with worse functional outcome at 14 days, but not at 28 days or 3 months.

CONCLUSION

Troponin I is associated with the development of ALI after SAH.

Overlapping features of eclampsia and postpartum angiopathy

INTRODUCTION

Postpartum cerebral angiopathy (PPA) is considered one of a diverse group of rare conditions termed "reversible cerebral vasoconstriction syndromes". Existing literature suggest considerable overlap in the manifestations of eclampsia and PPA.

METHODS

Retrospective case series review of PPA and eclampsia from a single neurosciences intensive care unit patient log identified over a consecutive 18-month period. A MEDLINE search (using OVID) of the English literature from 1950 through October 2008 was also performed.

RESULTS

Four patients who meet the obstetrical criteria for eclampsia and four patients whose clinical and radiographic features were consistent with PPA were identified. Twenty-eight patients with PPA were identified from the literature and showed significant clinical and radiographic overlap without cohort.

CONCLUSION

Given the overlapping clinical, laboratory, and radiographical features of eclampsia and PPA, it is probable they share a similar underlying pathophysiological mechanism and represent different clinical expressions of the same pregnancy-related disorder. The obstetrical definition of eclampsia may be to strict when applied in the neurosciences intensive care unit.

Fever burden and functional recovery after subarachnoid hemorrhage

OBJECTIVE

Fever is associated with worse outcome after subarachnoid hemorrhage, but there are few prospective data to quantify this relationship.

METHODS

We prospectively enrolled consecutive aneurysmal or cryptogenic subarachnoid hemorrhage patients and recorded the highest core temperature each calendar day for Day 0 (the day of hemorrhage) through Day 13. Fever burden was defined as the daily highest core temperature minus 100.4 degrees F, summed from admission through Day 13 (temperatures <100.4 degrees F did not contribute to or subtract from fever burden). Outcomes were assessed at 14 days or at the time of hospital discharge with the National Institutes of Health Stroke Scale and modified Rankin Scale, and at 28 days and 3 months with the modified Rankin Scale. Improvement was analyzed with repeated measures analysis of variance.

RESULTS

We prospectively enrolled 94 patients. From 14 days to 28 days to 3 months, functional improvement was related to cumulative fever burden, admission neurological grade, aneurysm obliteration procedure, admission computed tomographic score, vasospasm, and external ventricular drainage. Good-grade patients had worse functional outcomes with increased fever burden, and poor-grade patients improved more over time when fever burden was higher (time by World Federation of Neurological Surgeons grade by fever burden interaction, P < 0.001). Patients with vasospasm (P = 0.04) and patients with higher computed tomographic scores (P = 0.002) had worse 14-day outcomes but improved more over time. Bacteremia and ventriculitis were uncommon (<or=5%) and were not associated with higher fever burden.

CONCLUSION

Cumulative fever burden was associated with worse outcomes in good-grade patients and potential late recovery in poor-grade patients. Effective fever control in febrile subarachnoid hemorrhage patients may improve functional outcomes and hasten recovery.

How patients die after intracerebral hemorrhage

INTRODUCTION

Severity of illness scores predict all-cause mortality after intracerebral hemorrhage (ICH), but do not differentiate between proximate mechanisms or predict the timing. We hypothesized that death by neurologic criteria [brain death (BD)], withdrawal of life support, and cardiovascular death would be distinct after ICH.

METHODS

We prospectively enrolled patients with spontaneous ICH without underlying vascular malformation or neoplasm. We recorded clinical data and the proximate mechanism of death (BD, withdrawal of life support, cardiovascular death, or other cause). Time to death was compared with Kaplan-Meier methods (log-rank test). Data are median (IQR).

RESULTS

Among 89 patients, 15 had withdrawal of life support, 5 had BD, 2 died from cardiac arrest, and 3 died from other causes. Among patients who died, ICH score, age, Glasgow Coma Scale, NIH Stroke Scale, and proximate cause were not associated with the proximate mechanism of death. The time to death was different (P < 0.001) depending on the proximate mechanism. Patients with BD died 1 [0-1] 1 day after ICH, withdrawal of life support led to death 5 [1-13] days after ICH, cardiac death occurred 35 [35-85] days after ICH, and other causes led to death 33 [26-33] days after ICH. Among patients where life support was withdrawn, a higher ICH score on admission was related to earlier death (P = 0.002).

CONCLUSIONS

Proximate mechanisms of death after ICH occur at distinct times. Withdrawal of life support leads to earlier death in patients with a higher severity of injury. Medical causes of death can be effectively prevented after ICH.

Relationship between hemoglobin concentrations and outcomes across subgroups of patients with aneurysmal subarachnoid hemorrhage

OBJECTIVE

Anemia predicts poor outcome following aneurysmal subarachnoid hemorrhage (SAH). We hypothesized that this association would be stronger among patients with more severe SAH, since these patients are likely to be more vulnerable to secondary brain injury in the form of reduced cerebral oxygen delivery.

METHODS

Daily nadir hemoglobin (Hb) concentrations over 2 weeks following SAH were retrieved in 245 consecutive patients, and compared between those with a favorable versus unfavorable outcome. The analysis was repeated with patients dichotomized as follows: WFNS score 4-5 vs. 1-3; modified Fisher score (MFS) 4 vs. 0-3; and vasospasm present vs. absent. Mixed effect models and multivariable analysis using the generalized estimating equation were employed to assess correlated data with repeated measures.

RESULTS

Patients with an unfavorable outcome consistently had lower Hb concentrations, especially between days 6-11 following SAH (P ranging from <0.001 to 0.009), as well as a greater fall in Hb over time (beta = -0.07, P < 0.001). This was true regardless of WFNS score, MFS, or the presence or absence of vasospasm. However, the effect was somewhat more pronounced among patients with higher WFNS and modified Fisher scores.

CONCLUSION

Lower Hb levels are associated with worse outcomes regardless of SAH severity or the development of vasospasm. This finding may imply that a lower Hb concentration is largely a marker for a greater degree of systemic illness, rather than necessarily causing direct harm. However, the association is somewhat stronger among patients with more severe SAH. Thus, if there is a benefit for maintaining higher Hb levels with transfusions or erythropoietin, it may be more pronounced among these patients.

Barbiturates for the treatment of intracranial hypertension after traumatic brain injury

In their article on the use of barbiturates for the treatment of intracranial hypertension after traumatic brain injury, Perez-Barcena and colleagues conclude that thiopental was more effective than pentobarbital in decreasing intracranial pressure. Here we discuss the limitations of this study and review areas of controversy surrounding barbiturate use in neurocritical care.

Medical complications drive length of stay after brain hemorrhage: a cohort study

INTRODUCTION

Longer length of stay (LOS) is associated with higher complications and costs in ICU patients, while hospital protocols may decrease complications and LOS. We hypothesized that medical complications would increase LOS after spontaneous subarachnoid (SAH) and intracerebral (ICH) hemorrhage after accounting for severity of neurologic injury in a cohort of consecutively admitted patients.

METHODS

We prospectively recorded admission characteristics, hospital complications, and LOS for 122 patients with SAH and 56 patients with ICH from February 2006 through March 2008. A multidisciplinary Neuro-ICU team included a dedicated pharmacist and intensivist on daily rounds. Hospital protocols set glucose control with intravenous insulin, ventilator bundles, pharmacist involvement, and hand hygiene. Associations were explored with univariate statistics (t-tests, ANOVA, or non-parametric statistics as appropriate) and linear regression (repeated after log transformation of ICU and hospital LOS).

RESULTS

Factors associated with longer LOS after SAH and ICH were similar. In both SAH and ICH the strongest drivers of LOS were infection, fever, and acute lung injury. For SAH, vasospasm and Glasgow Coma Scale were also significant in some models, while in patients with ICH the volume of the initial bleed was significant in some models.

CONCLUSION

LOS after spontaneous brain hemorrhage is driven by medical complications even after the adoption of dedicated intensive care medical staff, pharmacist involvement, and evidence-based protocols for ICU care. Further alterations in care will be necessary to eliminate "preventable" complications and minimize LOS after brain hemorrhage.

Implications of early versus late bilateral pulmonary infiltrates in patients with aneurysmal subarachnoid hemorrhage

INTRODUCTION

Bilateral pulmonary infiltrates occur frequently following aneurysmal subarachnoid hemorrhage (SAH), and may be associated with worse outcomes. The etiology, natural history, and prognosis of infiltrates occurring soon after SAH may differ from the characteristics of infiltrates developing at a later time.

METHODS

We performed a retrospective cohort study involving 245 consecutive patients with a ruptured cerebral aneurysm to assess the association between "early" (< or = 72 h) or "late" (>72 h) bilateral pulmonary infiltrates and subsequent death or neurologic impairment. We used logistic regression models to adjust for baseline differences in age, level of consciousness, amount of blood on computed tomography, and the presence or absence of clinical vasospasm.

RESULTS

Sixty-seven patients (27%) developed bilateral pulmonary infiltrates. Of these, 36 (54%) had early infiltrates, 24 (36%) had late infiltrates, and 7 (10%) had both. Twenty-eight patients (11% of entire cohort) met criteria for acute respiratory distress syndrome (ARDS). Patients with early infiltrates were more likely to have presented with stupor or coma than patients who developed infiltrates later (64% vs. 29%, P < 0.01). In multivariable analysis, late pulmonary infiltrates were strongly predictive of poor outcome (OR 5.0, 95% CI 1.9-13.6, P < 0.01), while early infiltrates were not (OR 1.2, 95% CI 0.5-3.0, P = 0.66).

CONCLUSIONS

Bilateral pulmonary infiltrates after SAH most often occur within three days of aneurysm rupture. However, only infiltrates occurring beyond this time are independently associated with poor outcome. Increased emphasis on the prevention of late pulmonary complications has the potential to improve outcomes in SAH.