Prescription of Epinephrine Auto-injectors - Can we reach a consensus?

A consensus view of Irish Clinical Immunologists as to when auto injection syringes of adrenaline should be prescribed

Bronchiolitis

INTRODUCTION: Bronchiolitis is the most common lower respiratory tract infection in infants, occurring in a seasonal pattern, with highest incidence in the winter in temperate climates and in the rainy season in warmer countries. Bronchiolitis is a common reason for attendance at and admission to hospital.

METHODS AND OUTCOMES: We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of prophylactic interventions for bronchiolitis in high-risk children? What are the effects of measures to prevent transmission of bronchiolitis in hospital? What are the effects of treatments for children with bronchiolitis? We searched: Medline, Embase, The Cochrane Library, and other important databases up to July 2010 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS: We found 59 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS: In this systematic review we present information relating to the effectiveness and safety of the following interventions: antibiotics, bronchodilators (oral, inhaled salbutamol, inhaled adrenaline [epinephrine], hypertonic saline), chest physiotherapy, continuous positive airway pressure, corticosteroids, fluid management, heliox, montelukast, nasal decongestants, nursing interventions (cohort segregation, hand washing, gowns, masks, gloves, and goggles), oxygen, respiratory syncytial virus immunoglobulins, pooled immunoglobulins, or palivizumab (monoclonal antibody), ribavirin, or surfactants.

The use of topical anaesthesia during repair of minor lacerations in Departments of Emergency Medicine:a literature review

There are currently a number of different methods available to obtain anaesthesia in minor dermatological procedures. Although intradermal infiltration of 1% lidocaine is the favoured method for anaesthesia induction in laceration repair, it can cause significant pain in itself. Topical anaesthesia has been investigated as an alternative to infiltration anaesthesia, with the majority of studies looking at preparations of either TAC (tetracaine, adrenaline and cocaine) or LAT (lidocaine, adrenaline and tetracaine).

Variants in the catechol-o-methyltransferase (COMT) gene are associated with schizophrenia in Irish high-density families

The enzyme catechol-o-methyltransferase (COMT) transfers a methyl group from adenosylmethionine to catecholamines including the neurotransmitters dopamine, epinephrine and norepinephrine. This methylation results in the degradation of catecholamines. The involvement of the COMT gene in the metabolic pathway of these neurotransmitters has made it an attractive candidate gene for many psychiatric disorders. In this article, we reported our study of association of COMT with schizophrenia in Irish families with a high density of schizophrenia. Three single nucleotide polymorphisms (SNPs) were genotyped for the 274 such families and within-family transmission disequilibrium tests were performed. SNP rs4680, which is the functional Val/Met polymorphism, showed modest association with the disease by the TRANSMIT, FBAT and PDT programs, while the other two SNPs were negative. These SNPs showed lower level of LDs with each other in the Irish subjects than in Ashkenazi Jews. Haplotype analysis indicated that a haplotype, haplotype A-G-A for SNPs rs737865-rs4680-rs165599, was preferentially transmitted to the affected subjects. This was different from the reported G-G-G haplotype found in Ashkenazi Jews, but both haplotypes shared the Val allele. We concluded that COMT gene is associated with schizophrenia and carries a small but significant risk to the susceptibility in the Irish subjects.

Biomolecular Mechanisms of Pseudomonas aeruginosa and Escherichia coli Biofilm Formation

Pseudomonas aeruginosa and Escherichia coli are the most prevalent Gram-negative biofilm forming medical device associated pathogens, particularly with respect to catheter associated urinary tract infections. In a similar manner to Gram-positive bacteria, Gram-negative biofilm formation is fundamentally determined by a series of steps outlined more fully in this review, namely adhesion, cellular aggregation, and the production of an extracellular polymeric matrix. More specifically this review will explore the biosynthesis and role of pili and flagella in Gram-negative adhesion and accumulation on surfaces in Pseudomonas aeruginosa and Escherichia coli. The process of biofilm maturation is compared and contrasted in both species, namely the production of the exopolysaccharides via the polysaccharide synthesis locus (Psl), pellicle Formation (Pel) and alginic acid synthesis in Pseudomonas aeruginosa, and UDP-4-amino-4-deoxy-l-arabinose and colonic acid synthesis in Escherichia coli. An emphasis is placed on the importance of the LuxR homologue sdiA; the luxS/autoinducer-II; an autoinducer-III/epinephrine/norepinephrine and indole mediated Quorum sensing systems in enabling Gram-negative bacteria to adapt to their environments. The majority of Gram-negative biofilms consist of polysaccharides of a simple sugar structure (either homo- or heteropolysaccharides) that provide an optimum environment for the survival and maturation of bacteria, allowing them to display increased resistance to antibiotics and predation.

Autonomic modification of intestinal smooth muscle contractility

Intestinal smooth muscle contracts rhythmically in the absence of nerve and hormonal stimulation because of the activity of pacemaker cells between and within the muscle layers. This means that the autonomic nervous system modifies rather than initiates intestinal contractions. The practical described here gives students an opportunity to observe this spontaneous activity and its modification by agents associated with parasympathetic and sympathetic nerve activity. A section of the rabbit small intestine is suspended in an organ bath, and the use of a pressure transducer and data-acquisition software allows the measurement of tension generated by the smooth muscle of intestinal walls. The application of the parasympathetic neurotransmitter ACh at varying concentrations allows students to observe an increase in intestinal smooth muscle tone with increasing concentrations of this muscarinic receptor agonist. Construction of a concentration-effect curve allows students to calculate an EC50 value for ACh and consider some basic concepts surrounding receptor occupancy and activation. Application of the hormone epinephrine to the precontracted intestine allows students to observe the inhibitory effects associated with sympathetic nerve activation. Introduction of the drug atropine to the preparation before a maximal concentration of ACh is applied allows students to observe the inhibitory effect of a competitive antagonist on the physiological response to a receptor agonist. The final experiment involves the observation of the depolarizing effect of K+ on smooth muscle. Students are also invited to consider why the drugs atropine, codeine, loperamide, and botulinum toxin have medicinal uses in the management of gastrointestinal problems.