Occupational exposure to isoflurane during anaesthesia induction with standard and scavenging double masks in dogs, pigs and ponies.

This study explores the workplace pollution caused by the induction of anaesthesia on different animals using a standard face mask versus a scavenging double face mask. The scientists found notable differences in the level of the anaesthetic, isoflurane, in the air regardless of the type of mask used, with scavenging masks being recommended to reduce pollution.

Research Objective and Methodology

• The study aimed to assess the impact of a standard mask and a scavenging double mask on the presence of isoflurane in the surrounding air during anesthesia induction in specific animals like dogs, pigs and ponies.
• The experiments involved six dogs, twelve pigs, and five ponies. Dogs and ponies underwent anaesthesia twice – each time with a different mask, while pigs were only anaesthetized once.
• Different fresh gas flow rates and systems were used for animals of different size; The masks were attached to a Bain breathing system for dogs and pigs, while a circle system was used for ponies.
• Isoflurane concentrations in the area immediately surrounding the anaesthetist were measured using an infrared photoacoustic spectrometer.
• Data was statistically analyzed for both the peak isoflurane levels during baseline and induction periods and the different mask types using Wilcoxon or Mann-Whitney tests.

Research Findings

• The research found that the pollution levels were higher during the induction period in comparison to the baseline for both types of masks. This increase was statistically significant for dogs and pigs.
• Isoflurane pollution was lower when induction was performed with the double mask in comparison to the single mask. This was statistically significant only in pigs.
• Even though the decrease in pollution with the use of double masks wasn’t statistically significant in all cases, the team noted a consistent difference across all the species studied.

Conclusion

• The study concluded that induction of anaesthesia can cause workplace pollution with isoflurane.
• While the use of double masks helps reduce this pollution, the extent of reduction wasn’t significant in all species.
• Despite this, the consistent presence of a difference across all species suggests that scavenging masks could be a safer option to minimize workplace pollution.