Autoinjectors

Areas with a higher socioeconomic status seem to be related to an increased number of anaphylactic reactions [44-46]. Data from Canada and Wales indicate that prescriptions for epinephrine autoinjectors were higher in populations of relative wealth, whereas these findings could not be explained by access to medical care or other factors. 

A major progress in the field is the availability of epinephrine autoinjectors which can be used by the patient him-/herself as a self-medication. Different devices are available which either trigger the injection needle just by pressure on the thigh or which have to be triggered by pressing on a button (like a pencil). The handling of these devices has to be explained and practiced with the patients (see Management, Education) [37-40]. 

Educate patients in handling the situation of an anaphylactic reaction and the necessary medication including the handling of autoinjectors... 

In this review, we will describe the pharmacologic activity of epinephrine in anaphylaxis, the evidence base for its use, epinephrine dosing and routes of administration, epinephrine autoinjector use in first-aid treatment, reasons for failure to inject epinephrine promptly, reasons for occasional apparent lack of response, and future directions in epinephrine research. 

Optimal use of epinephrine autoinjectors for first-aid treatment of anaphylaxis in community settings is hampered by several issues. In most countries, these include the availability of only two pre-measured epinephrine doses and only a few different needle lengths, and the need to replace outdated autoinjectors at 12- to 18-month intervals due to degradation of the epinephrine solution they contain. 

Physicians face a dilemma with regard to prescribing an optimal epinephrine dose in an autoinjector for first-aid treatment of people at risk for anaphylaxis in a community setting, because only two pre-measured epinephrine doses, 0.15 and 0.3 mg, are... 

For overweight adolescents and adults, autoinjectors containing a 0.5-mg dose of epinephrine are needed however, this dose is not available in most countries. Moreover, in many overweight people, attempts to inject epinephrine intramuscularly from most currently available autoinjectors are likely doomed to failure, because the attached needle is too short to penetrate the poorly vascularized adipose tissue layer over the vastus lateralis [26]. 

Lack of appropriate dose options and needle length options should not deter physicians from prescribing epinephrine autoinjectors for the first-aid out-of-hospital treatment of anaphylaxis. 

Currently, many physicians advise their patients at risk for anaphylaxis in the community to carry two epinephrine doses with them at all times [30]. In school settings, it has been proposed that one epinephrine autoinjector should be available for each child at risk, along with several extra autoinjectors available as back-up for all children at risk [31]. 

Although epinephrine autoinjectors are widely dispensed for first-aid treatment of anaphylaxis in some countries, they are neither available nor affordable in many others [33]. In these situations, physicians sometimes equip patients at risk for anaphylaxis in the community with an epinephrine ampule and a disposable 1-ml syringe. Some physicians also recommend this approach for infants, for whom, as noted previously, no appropriate epinephrine dose is available in an autoinjector formulation. 

Some physicians recommend epinephrine metered-dose inhalers as an alternative to epinephrine autoinjectors. While a few inhalations might relieve mild or moderate respiratory symptoms, for relief of life-threatening airway obstruction or shock, adults need to inhale 20-30 puffs and children need to inhale 10-20 puffs, which is hard to do [35]. Epinephrine metered-dose inhalers contain chlorofluorocarbon propellants. For environmental reasons, they might not be manufactured in the future. 

Published clinical scenarios outline the available options in making these decisions [36], It is impossible to predict the outcome of a future anaphylaxis episode with certainty based on the history of a previous episode [37]. Therefore, when in doubt, erring on the side of caution is generally advised prescribe one or more epinephrine autoinjectors, and advise the person at risk or the caregiver of a child at risk to inject epinephrine promptly in an anaphylaxis episode [36]. 

Many people who have experienced anaphylaxis in the community and are therefore at risk for recurrence have never received a prescription for an epinephrine autoinjector from an emergency department physician [38, 39] or from their primary care physician. Some of those who have received a prescription for an epinephrine autoinjector do not follow through and get it filled [40]. Even if they do get the epinephrine autoinjector dispensed, they may fail to carry it with them at all times [41]. Adherence to instructions to carry epinephrine can be improved with regular input from a healthcare professional [42] however, healthcare professionals need to master the complexities of epinephrine autoinjector use [43] before instructing others. People who have survived a mild anaphylaxis episode that was not treated at all, or was treated only with an antihistamine or an asthma puffer, sometimes fail to inject epinephrine because they erroneously assume that their subsequent reactions will also be mild [44]. 

Preparedness for first-aid treatment of anaphylaxis in the community involves not only a prescription for epinephrine autoinjectors, but also an Anaphylaxis Emergency Action Plan, appropriate medical identification, and anaphylaxis education. 

Epinephrine autoinjectors should be prescribed in the context of a written Anaphylaxis Emergency Action Plan that is developed with the input of the person at risk for anaphylaxis, or the caregiver(s) of the child at risk [45]. The Plan should remind the person at risk about the common symptoms and signs of anaphylaxis, stress the importance of prompt epinephrine injection, and clearly state that Hj-antihistamines... 

Chowdhury BA Adequacy of the epinephrine autoinjector needle length in delivering epinephrine to the intramuscular tissues. Ann Allergy Asthma 41 Immunol 2005 94 539-542. 

Simons FER Lack of worldwide availability of epinephrine autoinjectors for outpatients at risk of anaphylaxis. Ann Allergy Asthma Immunol 2005 94 534-538. 

A stream of ethylene is fed into the reactor by use of quaternary LC pumps and subsequently dissolved in a 1.90 ml h toluene stream [1]. Ethylene is handled at 60 °C, well above the critical temperature. Catalyst additions are fed via HPLC-type sample injection valves. Various combinations of precatalysts and activators were sampled and loaded by an autoinjector. Catalyst solutions typically were diluted 20-fold within the micro reactor. 

In addition, further automation will be needed in what is still very much a hands-on art. Autoinjectors coupled to complete analytical data systems and readers for 96-well plates are the beginning of what will continue to be a necessary trend of residue chemistry. The application of the techniques of combinatorial chemistry/biochemistry, which has produced screening methodology for handling many variables, might be appropriate to residue chemistry. 

Hewlett-Packard Model 6890 gas chromatograph with capillary split/splitless inlet with HP5973 mass-selective detector equipped with an autosampler Shimadzu GC17A gas chromatograph with capillary split/splitless inlet with flame thermionic detector equipped with an AOC-17 autoinjector... 

Under some conditions, it is difficult to incorporate an internal standard into a method. If the chromatogram is very complex, an internal standard may interfere with quantitation of a peak of interest. The development of highly precise sample transfer techniques, including modem autoinjectors, reduces the dependence of the experimentalist on the use of an internal standard to correct for effects of dilution and transfer losses. In many cases, external standardization can be used effectively. The weight percent purity is determined by comparing the area of each peak in a chromatogram with those generated by separately injected pure standards of known concentration. 

Sumatriptan is available for oral, intranasal, and SC administration. The SC injection is packaged as an autoinjector device for self-administration by patients. When compared with the oral formulation, SC administration offers enhanced efficacy and a more rapid onset of action (10 vs. 30 minutes). Intranasal sumatriptan also has a faster onset of effect (15 minutes) than the oral formulation and produces similar rates of response. Approximately 30% to 40% of patients who respond to sumatriptan experience headache recurrence within 24 hours a second dose given at the time of recurrence is usually effective. However, routine administration of a second oral or SC dose does not improve initial efficacy rates or prevent subsequent recurrence. 

Intracavernosal alprostadil should be injected 5 to 10 minutes before intercourse using a 0.5-inch, 27- or 30-gauge needle or an autoinjector. The maximum number of injections is one per day and three per week. 

INGESTION Do not induce vomiting. First symptoms are likely to be gastrointestinal. Immediately administer an intramuscular injection of the MARK I kit autoinjectors. SEEK MEDICAL ATTENTION IMMEDIATELY. 

LC 6A system comprising SCL-6A controller, SPD-6A and SPD-6AV spectrophotometric detectors, CTO-6A column oven, LC-6A pump, SIL-6A autoinjector... 

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