Safety Devices
Slide 2
Three kinds of safety devices are presently available and these are auto disable (AD) and reuse prevention  syringes for minimizing spread of blood borne pathogens patient to patient, health care worker safety devices to prevent needle stick injury, and point of use disposal devices.
Slide 3
The development AD syringes was in response to the pandemic HIV and fears that unsafe injection practices may make children infected early during immunization programs. A competition was held by USAID and three designs were selected for further development out of these three a hydro gel syringe developed by John Hopkins University was found not feasible for commercial production. The other two designs were commercialized under an agreement between PATH and BD and the first AD syringe named Soloshot was introduced in the Immunization programs after extensive field testing and validation by WHO in Pakistan. The original WHO performance criteria were surpassed in all aspects by this syringe.
Slide 4
Two types of Auto disable and reuse prevention technologies are available world wide. The active mechanism syringes need to be actively disabled by the user and there is always a possibility of reuse if the mechanism is nit activated.
The passive mechanism activated automatically as soon as the drug is fully injected out the user has no control over the mechanism hence the chances of reuse are nearly zero.
Slide 5 and 6
The immunization AD syringe is now available for use in EPI. WHO, UNICEF and UNFPA have in joint statement recommended that all EPI programs should start using AD syringes from 2004. GAVI is also giving support to all eligible countries only for AD syringes
Slide 7
The syringe shown here is the latest avatar of the original Solo shot AD syringe introduced in 1991 by UNICEF and WHO in EPI. Eight other manufacturers are also qualified by WHO to manufacture immunization AD the specification applied by WHO for qualifying these devices is knows as E8/DS1, which specifies that the needle should be 23 gauge and 1 inch long. The syringe has permanently attached needle with dead space of less than 28microlitres a study done in Indonesia showed that using Solo shot AD actually helped bring down vaccine wastage and saving of 15% more vaccine were seen, The AD mechanism is determined by a V clip in the syringe which gets activated as soon as the forward movement of the plunger is started and hence the plunger cannot be pulled back again. The Syringe has only preset volume markings of 0 and 0.5 ml which help in accurate dosage withdrawal and administration.
The same type of syringes is Available for BCG with Preset Vol marking of 0 and 0.05 ml/0.1 ml/Dual marking with 0.5 and 0.1 ml.
Government of India Has already has taken a conscious decision to convert the EPI program to AD Syringes from 2005.
Slide 8 & 9
Prefilled auto-disable devices also known as UNIJECT were also developed by PATH and then given to BD for commercial development, this is a simple device which has a pouch to fill in the drug and a needle to inject, These devices are provided to the vaccine & Pharma manufacturers to fill in the drug and then market .It provides for the simplicity of the drug cum an auto-disabling device rolled into one.
This device has 3 parts: The needle , One way valve mechanism and The pouch , when supplied the needle is separate from the drug filled pouch , to activate before injecting The needle is pushed back so that it punctures through the one way valve and comes in contact with the drug in the pouch , Then the needle is penetrated into the patient and the pouch squeezed to deliver the dose. Any attempt to refill is made impossible due to the presence of a one way valve.
This device has been used extensively by UNICEF for Tetanus campaigns in Africa and Indonesia; it has also been introduced into the Indian market with Hepatitis B Vaccine.
Slide 10,11 &12
80-85% of all injections given are for Curative purposes, hence to provide safety and minimize the chances of recycling and reuse after Disposal, Actively disabling AD syringes are now available in the market, These syringes offers a disabling mechanism which can be activated by the health care professional after he has completed the desired procedure and also prevents recycling and reuse after disposal.
The mechanism is simple, once the required procedure has been completed the plunger is pushed thereby breaking the plunger into two parts, there is an audible click when the plunger breaks into 2 parts which then cannot be refit, any attempt to reuse the barrel by pushing out the broken part is prevented by a retention ring nearing the opening of the barrel. These syringes are available in 2/5/10/20ml sizes in both 2 piece and 3 piece (with rubber stopper) platforms.
Slide 13
A new generation of passively disabling AD syringes is now being developed for curative purposes which would allow the plunger to be pulled back once for withdrawing, reconstituting solvents, injecting into the powder, redrawing and injecting into the patient. These kinds of syringes also allow a different volume to be aspirated and injected every time the plunger is moved ,for e.g. we can draw 5ml solvent in the first plunger movement to allow reconstitution and then only 2ml of solution redrawn and injected into the patient causing the mechanism to lock it. In other words ‘it is a dose sensing smart syringe’ and is expected to in the market by 2006.
Slide 14
The international standards organization is the process of fixing specifications for syringes with reuse prevention feature for immunization and curative use. The key specifications, describe the types of reuse prevention mechanisms that would be covered and also the intended use. It gives the methods for testing the reuse prevention feature. A common symbol/ logo for AD syringes are being designed. It will mandatory to affix this on all levels of packaging for AD syringes.   The specification for immunization will be known as ISO 7886-3 and for curative 7786-4. Once fully developed and finalized in consultation with all stakeholders, these will supersede the existing WHO criteria and specifications.
Slide 15
One of the areas for concern that has emerged is health care workers safety due to the growing recognition of the fact that health needle stick injuries for a major cause transmission of blood born pathogen. An article in Lancet published is 1984 claimed that the first documented case of HIV due to NSI in a health care professional happened the UK. Recognition of infections transmitted by sharps injury grew with an increasing understanding of the the modes of HIV transmission world wide. In 1987 Collins and Kennedy published a list of micro organisms known to have been transmitted  through  sharps. In a study published in the WHO bulletin in 1999 done Simonsen et al, demonstrates the estimated risk of infection following a NSI from an infected source patient has 30% for HBV, 3-6% for HCV and .3-1% for HIV. In contrast if we look around the most feared of these three is HIV which is the least infective. Many HCP are still not immunized with three doses of Hep B vaccine and of those vaccinated most do not get their serum antibodies estimated to confirm seroconversion. In the US a growing concern due to sustained surveillance of NSI led the then President Clinton promulgate a federal law in 2000 requiring that all hospitals use only safety engineered products to be available in all hospitals across US by April 18, 2001 and this also provided for all employers whose employees could be exposed to blood born pathogens to insure that they protected against the risk of sharps injury.
Slide 16
Needle shielding device these were one of the first safety engineered devices made available and required single handed activation by pushing the shield after the injection is over to go and cover the needle tip.
Slide 17
Safety cannula’s , these are basically the IV cannula or catheter that are used for peripheral venous access these have a shield folded over the stylette, which goes and covers the tip of the stylette  as the cannula is inserted into the vein and the stylette is withdrawn.
 
Slide 18-19
These cannula’s do not have Iv port and once they are in the vein and the stylette withdrawn a simple push of the button  retracts the stylette into a holder thereby making it inaccessible
These are also available for pediatric patients.
Slide 20
Closed system catheter are available now which enable the HCP to gain IV access without getting exposed to any blood and enabling them to keep the IV lines open for drug and fluid delivery.
Slide 21
Evacuated blood collection systems with or without needle shields enable sample collection without
being exposed to blood.
Slide 22 – 24
Syringes, lancets and scalpels with features that can retract the sharps or have protracting shields are also available and minimize the risk of NSI.
Slide 25-26
Point of use disposal of sharps in puncture proof containers is the best way to prevent NSI on the job. Safety boxes are provided in immunization campaigns for collections of needles and syringes to be subsequently disposed of. A 5 letter box can contain as many as 150 syringes with needles. Hub cutters are now available which cut the hub of the needle and syringe containing the needle and cut hub in a puncture proof leak proof container. These can contain up to 500, 23 gauge x 1 inch needle and once full can be discarded. Patient room collectors are useful in facilities with high patient loads they can be kept in wards and rooms for immediate disposal of sharps and once full can be transported easily.
Slide 27
The overall message is that prevention is better than cure. We have to be Needle smart to prevent ourselves from needle stick injuries and becoming victims of our own devices.
Slide 28
Internet site for more information