Glycaemic control for patients with severe acute brain injury: Protocol for a systematic review

Background

Hyperglycaemia is common in patients with acute brain injury admitted to an intensive care unit (ICU). Many studies have found associations between development of hyperglycaemia and increased mortality in hospitalised patients. However, the optimal target for blood glucose control is unknown. We want to conduct a systematic review with meta-analysis and trial sequential analysis to explore the beneficial and harmful effects of restrictive versus liberal glucose control on patient outcomes in adults with severe acute brain injury.

Methods

We will systematically search medical databases including CENTRAL, Embase, MEDLINE and trial registries. We will search the following websites for ongoing or unpublished trials: http://www.controlled-trials.com/ , http://www.clinicaltrials.gov/ , www.eudraCT.com , http://centerwatch.com/ , The Cochrane Library's CENTRAL, PubMed, EMBASE, Science Citation Index Expanded and CINAHL. Two authors will independently review and select trials and extract data. We will include randomised trials comparing levels of glucose control in our analyses and observational studies will be included to address potential harms. The primary outcomes are defined as all-cause mortality, functional outcome and health-related quality of life. Secondary outcomes include serious adverse events including hypoglycaemia, length of ICU stay and duration of mechanical ventilation, and explorative outcomes including intracranial pressure and infection. Trial Sequential Analysis will be used to investigate the risk of type I error due to repetitive testing and to further explore imprecision. Quality of trials will be evaluated using the Cochrane Risk of Bias tool, and quality of evidence will be assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach.

Discussion

The results of the systematic review will be disseminated through peer-reviewed publication. With the review, we hope to inform future randomised clinical trials and improve clinical practice.     

Nedocromil sodium inhibits IgE- and IgG-related antigen-induced contraction in guinea-pig trachea

The effects of nedrocromil sodium and disodium cromoglycate were studied on the anaphylactic contraction of guinea-pig trachea in two models of active sensitization (IgE and IgG models). The influence of epithelial removal on the effects of nedocromil sodium and disodium cromoglycate was examined because several studies have shown that the epithelial layer can modulate agonist- or antigen-induced contractile responses. Disodium cromoglycate (10(-4) M) and nedocromil sodium (10(-4) M) provided significant protection against antigen-induced contractions of guinea-pig tracheal smooth muscle in the IgG model. But only nedocromil sodium had an effect at this concentration in the IgG model and was also effective at 10(-5) M in the epithelium-denuded tracheal strips. At this concentration, disodium cromoglycate lost its protective effect. Comparison with the results obtained with FPL-55712, AA-861 and mepyramine suggested that these drugs affect histamine and particularly leukotriene synthesis and/or release by mast cells or other immunocompetent cells. These findings indicate that nedocromil sodium inhibits the IgE- and IgG-related antigen-induced contraction in guinea-pig airways, whereas disodium cromoglycate inhibits only the IgG-related processes. This study supports the hypothesis that these drugs modulate antigen-induced mediator synthesis and/or release from immunocompetent cells.     

Residual Paralysis in the PACU after a Single Intubating Dose of Nondepolarizing Muscle Relaxant with an Intermediate Duration of Action

Background: Residual neuromuscular blockade remains a problem even after short surgical procedures. The train-of-four (TOF) ratio at the adductor pollicis required to avoid residual paralysis is now considered to be at least 0.9. The incidence of residual paralysis using this new threshold is not known, especially after a single intubating dose of intermediate-duration nondepolarizing relaxant. Therefore, the aim of the study was to determine the incidence of residual paralysis in the postanesthesia care unit after a single intubating dose of twice the ED95 of a nondepolarizing muscle relaxant with an intermediate duration of action.

Methods: Five hundred twenty-six patients were enrolled. They received a single dose of vecuronium, rocuronium, or atracurium to facilitate tracheal intubation and received no more relaxant thereafter. Neuromuscular blockade was not reversed at the end of the procedure. On arrival in the postanesthesia care unit, the TOF ratio was measured at the adductor pollicis, using acceleromyography. Head lift, tongue depressor test, and manual assessment of TOF and DBS fade were also performed. The time delay between the injection of muscle relaxant and quantitative measurement of neuromuscular blockade was calculated from computerized anesthetic records.

Results: The TOF ratios less than 0.7 and 0.9 were observed in 16% and 45% of the patients, respectively. Two hundred thirty-nine patients were tested 2 h or more after the administration of the muscle relaxant. Ten percent of these patients had a TOF ratio less than 0.7, and 37% had a TOF ratio less than 0.9. Clinical tests (head lift and tongue depressor) and manual assessment of fade showed a poor sensitivity (11-14%) to detect residual blockade (TOF < 0.9).     

Use of the Cytobrush for concurrent cytology and chlamydia sampling: a comparison of immunofluorescence and culture for detection of chlamydia

Five hundred and thirty-three women attending a genitourinary medicine clinic underwent concurrent cytology and Chlamydia trachomatis screening using a Cytobrush (Medscand AB). In each case, the same Cytobrush was used to give a sample for direct immunofluorescence and culture. 11.1% of samples were positive by immunofluorescence, while 10.6% were positive by culture. This was a close agreement (Kappa = 0.875). The ability of the same instrument to be used for both cytology and chlamydial screening, where direct immunofluorescence is used for detection of chlamydiae, may allow more widespread screening for chlamydia to be practical.