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Delivering a ‘Net Zero’ National Health Service

Mon, 11 Nov 2024 11:29:56 GMT

Greener NHS Provides a road map for a future Net Zero.

Roadmap

In 2022 Greener NHS published a guide to delivering a ‘Net Zero’ NHS. This document sets out the carbon footprint of the NHS; outlines direct interventions to decarbonise across five broad headings (estates, transport, supply chain, medicine and research) and outlines approaches required to deliver any reduction including sustainable models of care.

Targets

The target for the emissions controlled directly (the NHS Carbon Footprint), is to be net zero by 2040, with an ambition to reach an 80% reduction by 2028 to 2032.

Anaesthetic Gases

Anaesthetic gases comprise ~2% of the NHS carbon footprint. The target is to lower this by 40% through transforming anaesthetic practice including: switching to low carbon agents e.g. sevoflurane; employing capture / reuse technology and reducing atmospheric release from leftover nitrous gas canisters.

Nitrous Oxide

In addition, the capture and destruction of nitrous oxide could cut over one-third of NHS anaesthetic emissions. This technology has been readily deployed in Sweden for some 16 years and could save an estimated 90 ktCO2e emissions if implemented across 132 high impact trusts in the NHS. Scaled across the entire health service, this could deliver up to a 75% reduction in nitrous emissions.

Finally, significant carbon savings are available by decreasing nitrous oxide wastage, with the College of Paramedics estimating that 30% of nitrous oxide is left in canisters after use.

Greener NHS » Delivering a net zero NHS (england.nhs.uk)

User (midwife) Testing, University Hospital of Wales, Cardiff

Sat, 09 Nov 2024 08:05:44 GMT

The first production unit was introduced into a delivery suite at UHW, Cardiff mid-August and has been in regular use thereafter.

Feedback from midwives was collected both informally and via questionnaire.

Key takeaways:

Very positive and supportive of the project in terms of environmental benefit. Staff understand that Entonox is a greenhouse gas and that this machine reduces emissions.
Many staff feel it will improve their health and wellbeing by reducing their own exposure to nitrous oxide.
The machine was simple and easy to use
It was quiet
Although large, it was able to fit into the room ok
It could be used with a mouthpiece or face mask depending on patient choice
It did emit some heat, which although noticeable, didn't make the room uncomfortably hot

Performance testing at Wrexham Maelor Hospital

Sat, 09 Nov 2024 08:01:13 GMT

The ability of the N2O Clear product to eliminate nitrous oxide from an inlet stream was evaluated over 2 days at Wrexham Maelor Hospital, north Wales.

Using cylinder gas, test flows simulating 1~5 LPM of nitrous oxide and Entonox were introduced into the N2O Clear unit and the exhaust concentration of nitrous oxide was measured using a G200 N2O analyser from QED Environmental Systems.

% reduction in nitrous oxide between inlet and exhaust air was then calculated and determined to exceed the target 99% on all occasions.

Implementing nitrous oxide cracking technology in the labour ward

Fri, 08 Nov 2024 06:45:48 GMT

Implementing nitrous oxide cracking technology in the labour ward to reduce occupational exposure and environmental emissions: a quality improvement study.

A.Pinder, et al.

Anaaesthesia 2022, 77 , 1228-1236

2021-22 study to ascertain the impact of cracking technology on birthing room nitrous oxide levels.

Mean ambient nitrous oxide levels were recorded during the last 30 minutes of uncomplicated labours in 36 cases across 3 UK hospitals.

Baseline levels without the cracking unit were established over 12 readings: mean 45.4ppm, range 1.4-172.4ppm.

The cracking unit was then used with three different patient interfaces:

mouthpiece; 8 measurements: mean 13.05, range 0-64.9ppm; 71% lower vs baseline
cushion face mask; 8 measurements: mean 7.5ppm, range 0-234.2ppm; results were too variable to meet criteria for significance.
low profile face mask: 8 measurements: mean 8.7ppm, range 0-27.3ppm; 81% lower vs baseline.

22 midwives who used the equipment were surveyed with generally positive feedback.

19 commented that the unit “could be smaller”

8 reported faults with the cracking unit comprising 5 overheating events and 3 malfunctions.

4 described the noise level as unacceptable

The authors note a limitation of this quality improvement study was the lack of strict research protocols especially regarding patient selection/exclusion.

Occupational exposure of midwives to nitrous oxide on delivery suites.

Fri, 08 Nov 2024 06:39:55 GMT

K.A. Henderson, I.P. Matthews, A. Adisesh, A.D. Hutchings.

Occup Environ Med 20023; 60; 958-961

Study conducted prior to December 2002 using 40 midwives within 2 hospitals covering a total of 46 midwife shifts.

Passive diffusion tubes were used to determine workplace exposure to nitrous oxide during the first 4hrs of their shift. In addition, pre and post shift urine samples were collected to ascertain biological update.

During 35 out of the 46 midwife shifts exposure levels were greater than the 100ppm TWA occupational exposure limit. The measurement range was 2.4~1300ppm, mean 313ppm, s.d. 358ppm.

In 43 of the 46 instances nitrous oxide was detected in the midwife urine post shift. The measurement range was 0~1102µg/l, mean 114 µg/l, s.d. 191µg/l.

Adjusting for baseline urine levels, there was a statistically significant correlation between urinary concentration and environmental concentration of nitrous oxide (p<0.001).

It was noted that 14 of the 20 delivery rooms where the study was conducted had less than the recommended 5~6 air changes per hour.

Approximately half of the midwives had baseline nitrous oxide present in their pre-shift urine sample, which was viewed as a surprising finding. The authors went on to postulate that the clearance time for nitrous oxide may be longer that currently thought.