Brazilian Journal of Anesthesiology
Brazilian Journal of Anesthesiology
Clinical Research

Measurement of anesthetic pollution in veterinary operating rooms for small animals: Isoflurane pollution in a university veterinary hospital

Drielle B.S. Figueiredo, Aline G. Aun, Juliana R. Lara, Natache A. Garofalo, Francisco José Teixeira Neto, Leandro G. Braz, Mariana G. Braz

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Inhaled anesthetics are used worldwide for anesthesia maintenance both in human and veterinary operating rooms. High concentrations of anesthetic gas residues can lead to health risks for the professionals exposed. Considering that anesthetic pollution in a veterinary surgical center in developing countries is unknown, this study aimed, for the first time, to measure the residual concentration of isoflurane in the air of operating rooms for small animals in a Brazilian university hospital.

Residual isoflurane concentrations were measured by an infrared analyzer at the following sites: corner opposite to anesthesia machine; breathing zones of the surgeon, anesthesiologist, and patient (animal); and in front of the anesthesia machine at three time points, that is, 5, 30 and 120 minutes after anesthesia induction start time.

Mean residual isoflurane concentrations gradually increased in the corner opposite to anesthesia machine and in the breathing zones of the surgeon and the anesthesiologist (p <  0.05). There was an increase at 30 minutes and 120 minutes when compared to the initial time points in the animal's breathing zone, and in the front of the anesthesia machine (p <  0.05). There was no significant difference at measurement sites regardless of the moment of assessment.

This study reported high residual isoflurane concentrations in veterinary operating rooms without an exhaust system, that exceeds the limit recommended by an international agency. Based on our findings, there is urgent need to implement exhaust systems to reduce anesthetic pollution and decrease occupational exposure.


Inhaled anesthetics;  Surgery center;  Veterinary surgery;  Air pollution;  Occupational exposure


1 E.P. Steffey, K.R. Mama, R.J. Brosnan Inhalation anesthetics KA Grimm, LA Lamont, WJ Tranquilli, SA Greene, SA Robertson (Eds.), Veterinary Anesthesia and Analgesia: the Fifth Edition of Lumb and Jones, John Wiley & Sons, Inc (2015), p. 297

2 EI Eger 2nd. New inhaled anesthetics Anesthesiology., 80 (1994), pp. 906-922

3 S. Safari, M. Motavaf, S.A. Seyed Siamdoust, S.M. Alavian Hepatotoxicity of halogenated inhalational anesthetics Iran Red Crescent Med J., 16 (2014), p. 20153

4 R. Nickalls, W. Mapleson Age-related iso-MAC charts for isoflurane, sevoflurane and desfurane in man Br J Anaesth., 91 (2003), pp. 170-174

5 NH Dodman, LA Lamb Survey of small animal anesthetic practice in Vermont J Am Anim Hosp Assoc., 28 (1992), pp. 439-444

6 R. Carareto, L.S. Rocha, P.N. Guerrero, et al. Retrospective study of the mortality and morbidity associated with general inhalant anesthesia in dogs Semina: Ciênc Agrár., 26 (2005), pp. 569-574

7 G Mastrangelo, V Comiati, M dell’Aquila, E Zamprogno Exposure to anesthetic gases and Parkinson’s disease: a case report BMC Neurol., 13 (2013), p. 194

8 T. Casale, T. Caciari, M.V. Rosati, et al. Anesthetic gases and occupationally exposed workers Environ Toxicol Pharmacol., 37 (2014), pp. 267-274

9 E.R. Costa Paes, M.G. Braz, J.T. Lima, et al. DNA damage and antioxidant status in medical residents occupationally exposed to waste anesthetic gases Acta Cir Bras., 29 (2014), pp. 280-286

10 K.M. Souza, L.G. Braz, F.R. Nogueira, et al. Occupational exposure to anesthetics leads to genomic instability, cytotoxicity and proliferative changes Mutat Res. (2016) 791-792:42-8

11 M.G. Braz, K.M. Souza, L.M.C. Lucio, et al. Detrimental effects detected in exfoliated buccal cells from anesthesiology medical residents occupationally exposed to inhalation anesthetics: An observational study Mutat Res., 832-833 (2018), pp. 61-64

12 K. Hoerauf, M. Lierz, G. Wiesner, et al. Genetic damage in operating room personnel exposed to isoflurane and nitrous oxide Occup Environ Med., 56 (1999), pp. 433-437

13 T. Epp, C. Waldner Occupational health hazards in veterinary medicine: physical, psychological, and chemical hazards Can Vet J., 53 (2012), pp. 151-157

14 A.C. Macedo, V.T. Mota, J.M. Tavares, et al. Work environment and occupational risk assessment for small animal Portuguese veterinary activities J Occup Environ Hyg., 15 (2018), pp. D19-D28

15 NIOSH Criteria for a recommended standard: occupational exposure to anesthetic gases and vapors. The National Institute for Occupational Safety and Health of the United States of America (1977)

16 R.J. Gardner, J. Hampton, J.S. Causton Inhalation anaesthetics: exposure and control during veterinary surgery Ann Occup Hyg., 35 (1991), pp. 377-388

17 RE Korczynski Anesthetic gas exposure in veterinary clinics Appl Occup Environ Hyg., 14 (1999), pp. 384-390

18 S. Friembichler, P. Coppens, H. Säre, Y. Moens A scavenging double mask to reduce workplace contamination during mask induction of inhalation anesthesia in dogs Acta Vet Scand., 53 (2011), p. 1

19 H. Säre, T.D. Ambrisko, Y. Moens Occupational exposure to isoflurane during anaesthesia induction with standard and scavenging double masks in dogs, pigs and ponies Lab Anim., 45 (2011), pp. 191-195

20 K.R. Johnstone, C. Lau, J.L. Whitelaw Evaluation of waste isoflurane gas exposure during rodent surgery in an Australian university J Occup Environ Hyg., 14 (2017), pp. 955-964

21 D. Newcomer, I. Chopra Evaluation of waste anesthetic gas surveillance program and isoflurane exposures during animal and human surgery J Occup Environ Hyg., 16 (2019), pp. 544-556

22 L.G. Braz, J.R.C. Braz, G.A. Cavalcante, et al. Comparison of waste anesthetic gases in operating rooms with or without an scavenging system in a Brazilian University Hospital Rev Bras Anestesiol., 67 (2017), pp. 516-520

23 A. Shirangi, L. Fritschi, C.D. Holman Associations of unscavenged anesthetic gases and long working hours with preterm delivery in female veterinarians Obstet Gynecol., 113 (2009), pp. 1008-1017

24 M.K. Vollmer, T.S. Rhee, M. Rigby, et al. Modern inhalation anesthetics: Potent greenhouse gases in the global atmosphere Geophys Res Lett., 42 (2015), pp. 1606-1611

25 CR Oliveira Occupational exposure to anesthetic gases residue Rev Bras Anestesiol., 59 (2009), pp. 110-124

26 L.M.C. Lucio, M.G. Braz, P.J. do Nascimento, J.R.C. Braz, L.G. Braz Occupational hazards, DNA damage, and oxidative stress on exposure to waste anesthetic gases Rev Bras Anestesiol., 68 (2018), pp. 33-41

27 Y. Ishizawa Special article: general anesthetic gases and the global environment Anesth Analg., 112 (2011), pp. 213-217

28 M.P. Sulbaek Andersen, S.P. Sander, O.J. Nielsen, D.S. Wagner, TJ Sanford Jr, TJ. Wallington Inhalation anaesthetics and climate change Br J Anaesth., 105 (2010), pp. 760-766

29 A.J. MacNeill, R. Lillywhite, C.J. Brown The impact of surgery on global climate: a carbon footprinting study of operating theatres in three health systems Lancet Planet Health., 1 (2017), pp. 381-388

30 R.S. Jones, E. West Environmental sustainability in veterinary anaesthesia Vet Anaesth Analg., 46 (2019), pp. 409-420

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