The economics of using sharp safety-engineered devices

Pete Phillips and Joanna Ford, SMTL

October 2008

Introduction

A range of sharp safey-engineered devices are available on the market designed to protect the user from a sharps injury following use. This report aims to summarise the economic considerations of introducing 'sharp safety' devices into the work place and attempts to demonstrate how the costs of these changes can be calculated.

Safety devices for the prevention of sharps injuries are designed to prevent re-use and injury to the user. As a result, they contain additional mechanisms and complex parts which can result in them being significantly more expensive than their conventional counterparts. However, if the use of these devices leads to a reduction in needlestick injury rates, this may result in associated cost savings.  The cost of using the new devices compared to the savings they may produce can help the NHS understand the economics involved in introducing the devices.  

Calculating costs for the prevention of injuries is not straightforward for a number of reasons:

• Information is not always readily available (e.g. many injuries are not reported).
• The true costs of professional time, testing, loss of work time and prophylactic treatment can be difficult to quantify.
• There is a real risk that personal injury claims will increase in the near future (Brewer, 2001) but the costs to the NHS are as yet unknown.
• Changes in disposal practices (such as requirement for larger sharps bins), changes in use of related supplies (such as compatible devices associated with the procedure) and changes in nursing time required to use new devices (Laufer and Chiarello 1995) cannot be readily quantified.

For these reasons, such calculations are only estimates. Finally and perhaps most importantly, factors such as pain, worry and stress caused by needlestick injuries from contaminated sharps cannot be easily or readily quantified. Therefore, weighing up the cost of needle protection devices against the reduced chance of health care workers sustaining sharps injuries and contracting blood borne viruses is not a simple economic exercise.

The costs of the following  should be considered in any financial analysis by health care workers:

• testing
• counselling
• administration
• follow up
• prophylactic and ongoing treatment
• legal costs
• lost output costs
• pain and suffering
• compensation costs
• price of conventional devices versus price of safety devices
• an estimation of the reduction in needlestick rate if a safety device were to be used

Device cost comparisons

The following table compares the prices (per item) of some conventional devices with 'safer' alternatives (information provided by manufacturers). Please note that the prices are approximate.

Conventional Device	Safety Device Alternatives
Syringe (Monoject) and needle, Tyco 3p	NMT safety syringe 36p	Vanish Point syringe 60p	Vanish Point syringe 27p	BD Eclipse 14p	BD Integra 29p
IV Catheter (Venflon), BD 62p	J+J Protectiv Plus £1	J+J Protectiv Acuvance 2 £1.60	NMT Vaxcess £1.21	B.Braun Vasofix safety £1.09	Safelon £1.10	Safelon Pro £1.08
Needle and suture, Ethicon £2	J+J Ethiguard blunt taperpoint £2.60
Butterfly, Abbott Labs 23p	ICU Med. Punctur guard 72p	Terumo Surflow winged infusion set 38p	Saf-T-Intima £1.40
Blood collection needle, Greiner 4.7p	ICU Med. Punctur guard 23p	Safety lock (Vanish Point) 35p
Blood collection set, Greiner 27p	Terumo Surshield sampling set 44p
Blood lancet, Greiner 10p	Owen Mumford Unistik 2 10p	BD Gene 9p

Which costs should be examined ?

i. Cost of the device

The unit price of the device is multiplied by the usage per year (the number of devices used by the Hospital/Trusts should be available from procurement). For safety devices, it is usual to calculate the cost using the same annual usage as the conventional device. This may not necessarily be accurate as the safety-mechanism prevents re-use or re-siting of the device compared to non-safety devices, and therefore usage may increase with the safety devices. Therefore  an individual hospital or Trust may wish to examine potential changes in usage levels in more detail and incorporate them into the financial analysis.

ii. Cost of the needlestick injury

To calculate the cost of needlestick injury from conventional devices, multiply the number of injuries sustained per year by use of the conventional device (usually available from Infection Control or Occupational Health Departments) by the estimated costs incurred per injury (information for injury costs are estimated in the literature. Note that the costs for high risk and low risk injuries are significantly different).

For safety devices, multiply the cost of injuries (as above) by the  assumed reduced chance of sustaining an injury with the safety device. For example, if the the safety device has been shown to reduce needlestick injury by 60%, the expected injury costs should be 40% of the costs incurred when conventional devices were used.

iii. Total cost

For both the conventional and safer devices, add the cost of the device to the cost of injury. The difference between totals will give you an estimate of the changes in cost that will result from the introduction of the safer device.

Breakdown of NSI costs - an example

The information within the following tables has been taken from the 'Becton Dickinson financial modeling tool for safety'. The first table details the costs of a low-risk injury.

Activity	Cost estimate	Source
Nursing time	£23/h	NHS Careers Pay and Benefits
Occupational health time	£16/h	Costs of Health and Social care 1999. Personal services Research Unit
Hepatitis B vaccination	£36.00	D Francis. J. Occ. Med. 1991
PEP clinic time and Dr. consultation	£35/h	A Netten. Personal services Research unit
Laboratory time	£17.00	Working Well Initiative, NHS, 2001
Blood tests	£36.68 (average of Hep. B, Hep. C and HIV test)	A. Reutter J. of Adv. Nursing 1997
Counselling	£16.94/h	Working Well Initiative, NHS, 2001
Management time	£17.53/h	Working Well Initiative, NHS, 2001
Accident investigation health and safety	£79.70 (average of IC nurse and consultant	Working Well Initiative, NHS, 2001
Time away from ward	£17.53/h	Working Well Initiative, NHS, 2001
Occupational health time (follow up)	£16/h	A. Netten, Personal services Research unit

The following table details some of the additional costs of a high risk injury

Activity	Cost estimate	Source
Post exposure prophylaxis treatment	£1,146	UK CMO Expert advisory group on AIDS, 2000
Hepatitis B treatment	£2,873.00	Various
Hepatitis C treatment	£16,707.00	Various
HIV treatment-asymptomatic phase	£13,714.00	NPMS steering group
HIV treatment-symptomatic phase	£14,644.00	NPMS steering group
Treatment of AIDS	£25,036.00	NPMS steering group

Basic cost calculations

The calculation for both conventional devices and safety devices is summarised in its simplest form:

Cd + Ci = Ct

 where

• Cd-cost of device
• Ci-cost of injury
• Ct-total cost

Compensation claims

The cost packages here do not include compensation costs which are increasingly a major feature following injuries in the workplace. In our own Trust, needlestick injury (without sero-conversion) claims have lead to compensation costs of between £1000 and £14,000 per case (data provided by Trust Health and Safety department). If sero-conversion took place as a result of a sharps injury, the compensation claims would be far greater.

Examples of cost calculations

i. Peripheral IV catheters

The following table calculates the approximate cost of introducing the J+J Protectiv Plus safety catheter. The following examples in this section are based on one of the Welsh NHS Trusts. Calculations are based on actual usage and injury data for the Trust in question. The 76% reduction in injury with the safety catheter has been suggested, based on a number of studies. The cost of low-risk injury (£311.38) has been taken from BD's costing package which BD state is based on literature. The results were produced when using the BD financial modelling tool.

	Conventional device	Safety device
Cost of device purchase	Usage x cost of device 47,546 x 62p = £29,478.52	Usage x cost of device 47,546 x £1 = £47,546
Cost of needlestick injury	No. injuries x estimated cost of low risk injury 7 x £311.38 = £2179.66	Cost of injury x % reduction in injury £2179.66 x 0.24 (76% reduction in injury) = £523.12
Total cost	£31,658.18	£48,069.12

This costing exercise estimates that, with a predicted injury decrease of 76%, introducing the safety IV catheter will cost the Trust in question an extra £17,000 per annum (approximately).

The J+J costing package uses injury costs presented in the Scottish Report (Paterson and Elder 2005). Cost of injury is divided into the following bands:

• Band A - Needlestick injuries which result in a blood borne disease (costs £10,000-£620,000)
• Band B - Needlestick injuries where source patients are known to be HIV or HVC positive but does not result in seroconversion (costs £3000-£5000)
• Band C - Downstream injuries where source patient cannot be traced (costs £1000-2000) 
• Band D - Low risk injuries that have been reported to A+E or occupational health (costs £50-£100)
• Band E - Rarely reported or unreported injuries (costs £10)

In the same way as the previous tables, the following tables calculate the approximate cost of introducing the J+J Protectiv Plus safety catheter into the same Welsh NHS Trust, using the same usage details, under a variety of scenarios depending on the severity of injury.

Scenario 1 - When all injuries are low risk

	Conventional device	Safety device
Cost of device purchase	£29,479.00	£47,546.00
Cost of needlestick injury	£700.00	£168.00
Total cost	£30,179.00	£47,714.00

Scenario 2 - When one of the injuries is a downstream injury

	Conventional device	Safety device
Cost of device purchase	£29,479.00	£47,546.00
Cost of injury	£2,600.00	£624.00
Total Cost	£32,079.00	£48,170.00

Scenario 3 - When one of the injuries is higher risk (i.e. the source patient is HIV positive)

	Conventional device	Safety device
Cost of device purchase	£29,479.00	£47,546.00
Cost of needlestick injury	£5,600.00	£1,344.00
Total Cost	£35,079.00	£48,890.00

In all the scenarios above, the safety device is more expensive to introduce than the conventional device but the cost of conventional devices increase as the injury costs increase. Such an exercise highlights the benefits of using such a software package, as the cost of introducing safety devices can be evaluated under different scenarios.

ii. Needles and syringes

The following table compares the cost of using conventional syringe and needles with the cost of the BD Eclipse safety syringe (needle with shield) using the BD costing package. There is no concrete data on reduction in NSI with needle and syringes so a reduction in injury of 75% was chosen to illustrate potential cost savings. The following table shows the cost implications when one out for the 40 previous injuries sustained from the use of syringes and needles was high risk:

The results show that introducing the new safer device could incur significant costs per year even though the cost of injury could be reduced considerably. Syringes and needles are the most used items and cause the most injuries. Some safety syringes cost over ten times as much as the conventional devices. Please note: since writing this report we have been made aware of needle shield/guards available which cost little more than their conventional counterparts.  

	Conventional device	Safety device
Cost of device purchase	2701,000 x 3p = £81,303	2701,000 x 14p = £378,140
Cost of needlestick injury	39 x £311.38 1 x £15,171 = £27,314	£27,314 x 0.25 = £6828
Total cost	£108,617	£384,968

iii. Butterfly devices

The following tables compare the cost of using the conventional butterfly with the cost of 2 types of safety butterfly. The reduction in injury with the safer device was calculated as 52% (taken from an American study where a similar safety device was evaluated (Mendelson et al., 2003)). Cost of low risk needlestick injury was taken from BD costing package.

	Conventional device	Safety device (Surflow)	Safety device (Punctur-guard)
Cost of device purchase	8244 x 23p = Â£1,896.12	8244 x 38p = Â£3,132.72	8244 x 72p = Â£5,935.68
Cost of needlestick injury	25 x £311.38 =£7,784.50	£7784.5 x 0.48 = Â£3,736.56	£7784.5 x 0.48 = Â£3,736.56
Total cost	£9,680.62	£6,869.28	£9,672.24

The results show that if the cheaper of the 2 safety devices were purchased, nearly £3000 is saved because the cost of needlestick injury is fairly high. If the more expensive safer device were purchased, the price would be approximately the same.

iv. Blood collection needles

The following tables compare the cost of using the conventional blood collection needle with the cost of 2 types of safety blood collection needle. The reduction in injury with the safer device was calculated as 76% (taken from a study where the Punctur-guard blood collection needle was evaluated (Public Health Service 1997). Cost of low risk needlestick injury was taken from BD costing package.

	Conventional device	Safety device (Puncture-guard)	Safety device (Vanishpoint)
Cost of device purchase	194,500 x 4.7p = Â£9,141.50	194,500 x 23p = Â£44,735.00	194,500 x 35p = Â£68,075.00
Cost of needlestick injury	8 x £311.38 = Â£2,491.00	£2491.04 x 0.24 = Â£597.85	£2491.04 x 0.24 = Â£597.85
Total cost	£11,632.54	£45,332.85	£68,672.85

The results show that the cheapest of the 2 safer devices would cost an extra £33,000 to introduce (with an approximate injury decrease of 76%).

IMPORTANT: None of the above scenarios account for injury/compensation costs after a needlestick injury results in transmission of a blood borne disease

Conclusion

Sharps injuries in health care settings are stressful for the user, can potentially cause blood borne infections and can incur significant costs to the NHS, especially if this results in transmission of a blood borne disease. Sharp safety devices are designed to prevent sharps injury following use and may be beneficial in reducing injury rates. Although they usually cost more than their conventional counterparts, overall cost savings are possible if injury rates decrease or transmission of blood borne infections are prevented.

Caveat: The figures in the cost calculations were provided in 2003 and are for reference only. Some references cited from the financial modelling tools are not readily available.

Bibliography

Brewer S. Needlestick awareness; working well campaign. 2001. Infection Control :The Medical Book; 163-164

Laufer F, Chiarello L. Application of cost-effectiveness methodology to the consideration of needlestick-prevention technology. 1995 American Journal of Infection Control:22 (2); 75-82

Mendelson M, Lin-Chen B, Bailey E, Kogan G, Goldbold J. Evaluation of a safety resheathable winged steel needle for prevention of percutaneous injuries associated with intravascular-access procedures among healthcare workers. 2003. Infection control and hospital epidemiology:24(2);105-112.

Paterson C and Elder A (2005). Safer sharp Devices: An evaluation of utility in NHS Scotland. A report for the Occupational Health and Safety Strategy Implementation group NHS Scotland. Scottish Executive Edinburgh.

Public health service. 1997. Evaluation of safety devices for preventing percutaneous injuries among health-care workers during phlebotomy procedures. MMWR:46 (2) ;21-25