Nitrous oxide, a potent greenhouse gas, is a common labour analgesic. One method which may reduce its carbon footprint is to `crack´the exhaled gas into nitrogen and oxygen using catalytic destruction. In this quality improvement project, based on environmental monitoring and staff feedback, we assessed the impact of nitrous oxide cracking technology in the maternity setting. Mean ambient nitrous oxide levels were recorded during the final 30 minutes of uncomplicated labour in 36 cases and plotted on a run chart. Interventions were implemented in four stages, comprising: stage 1, baseline (12 cases); stage 2, cracking with nitrous oxide delivered and scavenged via a mouthpiece (eight cases); stage 3, cracking with nitrous oxide via a facemask with an air-filled cushion (eight cases); stage 4, cracking with nitrous oxide via a low-profile facemask, and enhanced coaching on the use of the technology (eight cases). The median ambient nitrous oxide levels were 71% lower than baseline in stage 2 and 81% lower in stage 4. Staff feedback was generally positive, though some found the technology to be cumbersome; successful implementation relies on effective staff engagement. Our results indicate that cracking technology can reduce ambient nitrous oxide levels in the obstetric setting, with potential for reductions in environmental impacts and occupational exposure.

Bench experiments to investigate the effect of nitrous oxide cracking technology in ideal circumstancesNitrous oxide (N 2 O) is a potent greenhouse gas, and occupational exposure has potential health impacts for healthcare staff [1,2]. Although the use of N 2 O can often be

Nitrous oxide is a common choice of labour analgesia in many countries. However, its use is associated with significant cost to the environment as well as potential risks of long-term occupational exposure. Our hospital is one of a small number of healthcare providers in the United Kingdom trialling technology which catalytically destroys (`cracks´) nitrous oxide to reduce greenhouse gas emissions and occupational exposure. When used in the setting of inhaled analgesia, cracking technology relies on capturing the patient's exhaled breath via a facemask or mouthpiece, a technique which requires some user skill and may be challenging for patients. In this report, we present the case of a primiparous 35-year-old consultant anaesthetist, who used nitrous oxide cracking technology with inhaled nitrous oxide analgesia (via a facemask) during labour. We present the patient's experiences and discuss the implications of using such technology on ambient nitrous oxide levels in the delivery room. Notably, despite this patient's professional expertise and familiarity with facemask use, nitrous oxide remained detectable throughout her labour, although generally at low levels. This illustrates that whilst this technology has the potential to reduce ambient nitrous oxide levels, its efficacy may vary depending on how it is used, with implications for patient education and support.