Karen Blackhall

Anti-fibrinolytic agents in post partum haemorrhage: a systematic review

BackgroundPost partum haemorrhage is a leading cause of maternal death worldwide. It also contributes to maternal morbidity as women may require a hysterectomy to control bleeding, or may require a blood transfusion, which can transmit viral infections. Anti-fibrinolytic agents have been proposed as a treatment for post partum haemorrhage. We conducted a systematic review to assess the effectiveness and safety of anti-fibrinolytic agents in post partum bleeding.MethodsAll randomised controlled trials of anti-fibrinolytic agents given for bleeding during the postpartum period were included in this review. We searched Medline, PubMed, EMBASE, Cochrane Central Register of Controlled trials, Web of Science, metaRegister of controlled trials, LILACS, Reproductive Health Library, African healthline, POPLINE, MedCarib, CINAHL, Clinicaltrials.gov and the reference lists of eligible trials. Two authors extracted data. Methodological quality was assessed by evaluating allocation concealment. The primary outcome was maternal mortality. Secondary outcomes were blood loss, blood transfusion, hysterectomy, mean haemoglobin concentration, thrombo-embolic events and other adverse effects.ResultsWe identified three randomised controlled trials involving 461 participants. The trials compared tranexamic acid with no treatment and reported blood loss after delivery. In all three trials, allocation concealment was either inadequate or unclear. The administration of tranexamic acid was associated with a reduction in blood loss of 92 millilitres (95%CI 76 to 109). The most frequently reported adverse effect of tranexamic acid was nausea, although the increase was easily compatible with the play of chance (RR 4.63, 95%CI 0.23 to 95.14).ConclusionTranexamic acid may reduce blood loss in post partum haemorrhage. However, the quality of the currently available evidence is poor. Adequately powered, high quality randomised controlled trials are needed.

Prognostic models for the early care of trauma patients: a systematic review

BackgroundEarly identification of major trauma may contribute to timely emergency care and rapid transport to an appropriate health-care facility. Several prognostic trauma models have been developed to improve early clinical decision-making.MethodsWe systematically reviewed models for the early care of trauma patients that included 2 or more predictors obtained from the evaluation of an adult trauma victim, investigated their quality and described their characteristics.ResultsWe screened 4 939 records for eligibility and included 5 studies that derivate 5 prognostic models and 9 studies that validate one or more of these models in external populations. All prognostic models intended to change clinical practice, but none were tested in a randomised clinical trial. The variables and outcomes were valid, but only one model was derived in a low-income population. Systolic blood pressure and level of consciousness were applied as predictors in all models.ConclusionsThe general impression is that the models perform well in predicting survival. However, there are many areas for improvement, including model development, handling of missing data, analysis of continuous measures, impact and practicality analysis.

Finding studies for inclusion in systematic reviews of interventions for injury prevention - the importance of grey and unpublished literature

The inclusion of unpublished and grey literature is essential for minimizing the potential effects of publication bias. It is well known that published studies can not be assumed to be an accurate representation of the whole evidence base, as studies that show statistically significant, “positive” results are more likely to be published than those that do not.1 Consequently, if systematic reviews are limited to published studies, they risk excluding vital evidence and yielding inaccurate results, which are likely to be biased to positive results.2 Previous research has indicated that meta-analyses that exclude grey literature can lead to exaggerated estimates of intervention effects.34 It is therefore considered essential that active and extensive searching for unpublished and grey literature is undertaken as part of the review process for all CIG reviews, although we feel this to be particularly important for reviews of injury prevention interventions. …

Beta‐2 Receptor Antagonists for Traumatic Brain Injury: A Systematic Review of Controlled Trials in Animal Models

A systematic review and meta‐analysis of controlled trials was undertaken to assess the effects of beta‐2 receptor antagonists in animal models of traumatic brain injury (TBI). Database and reference list searches were performed to identify eligible studies. Outcome data were extracted on functional status, as measured by the grip test or neurological severity score (NSS), and cerebral edema, as measured by brain water content (BWC). Data were pooled using the random‐effects model. Seventeen controlled trials involving 817 animals were identified. Overall methodological quality was poor. Results from the grip test suggest that the treatment group maintained grip for a longer period than the control group; pooled weighted mean difference (WMD) = 8.28 (95% CI 5.78–10.78). The treatment group was found to have a lower NSS (i.e., better neurological function); pooled WMD =−3.28 (95% CI −4.72 to −1.85). Analysis of the cerebral edema data showed that the treatment group had a lower BWC than the control; pooled WMD =−0.42 (95% CI −0.59 to −0.26). There was evidence of statistical heterogeneity between comparisons for all outcomes. Evidence for small study effects was found for the grip test and BWC outcomes. The evidence from animal models of TBI suggests that beta‐2 receptor antagonists can improve functional outcome and lessen cerebral edema. However, the poor methodological quality of the included studies and presence of small study effects may have influenced these findings.

Road safety in low- and middle-income countries: a neglected research area

It is estimated that each year between 20 and 50 million people are disabled and 1.2 million people die as a result of road traffic crashes, with 90% of the deaths occurring in low- and middle-income countries (LMICs).1 Furthermore, whereas a decrease in deaths has been observed in high-income countries, this is not the case in LMICs, where deaths are projected to increase by 80% over the next 20 years to become the second leading cause in the global burden of disease ranking.1 The identification and implementation of effective preventive interventions are essential for tackling this growing epidemic. Systematic reviews of the evidence are vital for identifying and quantifying the effects of interventions, and their findings should have a …

How effective are some common treatments for traumatic brain injury

Surveys show that mannitol, hyperventilation, cerebrospinal fluid drainage, and barbiturates are commonly used in the United Kingdom, Europe, and the United States to treat traumatic brain injury.1 2 3 Yet the effects of such treatments are uncertain. Traumatic brain injury is a major cause of death and disability worldwide. Every year at least 10 million people sustain a traumatic brain injury serious enough to result in death or admission to hospital.4 Bearing in mind that almost half of all patients with traumatic brain injury experience long term disability5 6 and that most injury occurs in young adults, the medical, social, and financial burden is clear. The Cochrane Injuries Group maintains a specialised register of randomised controlled trials of interventions for traumatic brain injury and has searched extensively for trials evaluating the effects of mannitol, hyperventilation, cerebrospinal fluid drainage, and barbiturates. The group has also prepared, and regularly updates, systematic reviews to assess the effects of barbiturates,7 hyperventilation,8 and mannitol.9 In 1998 the Cochrane Injuries Group highlighted the absence of reliable evidence for the effectiveness of these four treatments10 when searches identified only three small trials of barbiturates,11 12 …

Searching for studies for inclusion in Cochrane Systematic Reviews on injury prevention.

The Cochrane Injuries Group (CIG) prepares and maintains Cochrane Systematic Reviews of interventions for the prevention, treatment, and rehabilitation of traumatic injury. In this edition of Cochrane Corner, we describe how to search for studies to be included in a systematic review. Researchers and policy makers may also find these strategies useful when conducting general literature reviews on injury topics. An adequate search is key to ensuring high quality of the resultant review. To achieve the aim of identifying all relevant evidence, sophisticated information searching techniques are required. It is, however, a challenge to devise a search strategy with the appropriate balance between sensitivity and specificity; a sensitive search is required in order to identify as much of the relevant evidence as possible, yet specificity is required to ensure that the review author is not forced to wade through extensive amounts of irrelevant information. Search methods for every review need careful consideration to ensure that eligible studies are not missed or rejected, which could compromise the review’s findings. Injury prevention reviews pose a particular challenge when it comes to searching, as much of the relevant evidence is present in sources that are not indexed on the major databases such as Medline, EMBASE, and PubMed. Thus, searching of other, sometimes less standard, resources is an important part of conducting such a review. For example, authors of some of the CIG’s interventions for road safety reviews have found that much relevant evidence can be identified from general internet searches and websites of related institutions such as the National …

Interventions for preventing injuries caused by impaired alertness in individuals with jet lag and shift work disorder.

This is the protocol for a review and there is no abstract. The objectives are as follows: To assess the effects of interventions for preventing injuries caused by impaired alertness in persons with jet lag or shift work disorder.