Title: A Questionnaire Survey on use of Low Flow Anesthesia by Anesthesiologists

Authors: Vivek Mahajan, Shailja Gupta

 DOI:  https://dx.doi.org/10.18535/jmscr/v5i12.157

Abstract

Background: The routine use of low flows can cut down anesthesia costs up to 75%. The amount of volatile anesthetic agents extracted is directly proportional to the fresh gas flow (FGF) into the breathing circuit and system. The present study was conducted to determine the pattern of LFA among anesthetists.

Materials & Methods: It included 250 anesthetists. A questionnaire was prepared and was distributed among them. The questionnaire contained two parts, the first part intended to collect general information such as years of experience in anesthesia, region of practice, subspecialty of the participant if any and the practice setting of the participant. The second part dealt with questions specific to the practice of LFA, use of oxygen analysers and agent analysers, routine use of ETCO2 monitors and bispectral index (BIS) monitors, type of anesthesia machine being used routinely, preferred carrier gas and volatile agent as well as the volatile agent in routine use.

Results: Out of 250 subjects, males were 120 and females were 130. The difference was non- significant (P-0.5). The years of experience of anesthesiologists were 0-5 years (85), 6-11 years (65), 11-15 years (40), 16-20 years (20), 21-25 years (25) and >25 years (15). The difference was significant (P-0.01). Region of practice was north India (150) and south India (100). The difference was significant (P-0.05). The specialty of use was general (85), Cardiac & Vascular (60), pediatric (76), critical care (20) and other (9). Practice setting was private (160) and government (90). The difference was significant (P-0.02). The availability of workstations, scavenging systems and minimum monitoring equipment were oxygen analyzers (100), agent analyzers (30), ETCO2 monitors (45), BIS monitors (8), work stations (55) and work stations with MAC (12). The difference was significant (P-0.02). The fresh flow rate was <0.5 L (12%), 0.5 L (15%), 0.5-1 L (32%), 1-1.5 L (13%), 1.5- 2 L (18%) and >2 L (10%). The difference was significant (P-0.05). The volatile agents used was halothane (40%), desflurane (17%), isoflurane (65%) and sevoflurane (70%). The difference was significant (P-0.01).

Conclusion: Low flow anesthesia is practiced by many anesthesiologists. There is a lack of adequate monitoring facilities and scavenging systems.

Keywords: Desflurane, Low flow anesthesia, Isoflurane.

References

  1. Cotter SM, Petros AJ, Doré CJ, Barber ND, White DC. Low‑flow anaesthesia. Practice, cost implications and accepta-bility. Anesthesia 1991; 46:1009‑
  2. Body SC, Fanikos J, DePeiro D, Philip JH, Segal BS. Individualized feedback of volatile agent use reduces fresh gas flow rate, but fails to favorably affect agent choice. Anesthesiology 1999; 90:1171‑
  3. Yasny JS, White J. Environmental implications of anesthetic gases. Anesth Prog. 2012; 59:154‑
  4. Occupational disease among operating room personnel: A national study. Report of an Ad Hoc Committee on the Effect of Trace Anesthetics on the Health of Operating Room Personnel, American Society of Anesthesiologists. Anesthesiology. 1974; 41:321‑
  5. Baum J. Low Flow Anaesthesia: The Theory and Practice of Low Flow, Minimal Flow and Closed System Anaesthesia. 2nd ed. Boston: Butterworth‑Heinemann; 2001.
  6. Mitra JK, Jain V, Sharma D, Prabhakar H, Dash HH. A Survey on use of nitrous oxide in current anaesthetic practice in India. Indian J Anaesth. 2007; 51:405‑
  7. Ravishankara AR, Daniel JS, Portmann RW. Nitrous oxide (N2O): The dominant ozone‑depleting substance emitted in the 21st century. Science. 2009; 326:123‑
  8. Hönemann C, Hagemann O, Doll D. Inhalational anaesthesia with low fresh gas flow. Indian J Anaesth. 2013; 57:345‑
  9. Baum JA, Aitkenhead AR. Low‑flow anaesthesia. Anaesthesia. 1995; 50: 37‑
  10. Goyal R, Kapoor MC. Anesthesia: Contributing to pollution? J Anaesthesiol Clin Pharmacol 2011; 27:435‑7.

Corresponding Author

Dr Shailja Gupta

Professor and Head, Department of Biochemistry,

Pacific Medical College and Hospital, Udaipur, Rajasthan