สาร Trifluoroacetic acid (TFA) ในปัสสาวะของบุคลากรห้องผ่าตัดโรงพยาบาลนครปฐม

บทคัดย่อ

Waste Anesthetic Gases are small amounts of volatile anesthetic gases that leak from the patient’s anesthetic breathing circuit into the air of operating rooms during delivery of anesthesia. These gases included both nitrous oxide and halogenated anesthetic gases such as halothane enflurane isoflurane desflurane and sevoflurane. Halcthane was commonly used in Thailand because of its potency and low cost. But many of the patients and health care workers were reported severe side effects "HaIothane hepatitis" from repeated exposure to halothane or long term exposed to low concentration of halothane in the environment of ORs.

This study aimed to study the impact to the health of OR personnel by monitored the metabolite of halothane "Trifluoroacetic acid" which excreted in urine and monitored the amount of halothane in the operating rooms air. Urine TFA was collected at the end of the working day and air sample of halothane was analysed by Foxboro MIRAN 1 BX using the technique of infrared spectrophotometry.

Results : The 1^st  Collection of urine TFA was done at September 2005. There were 83.78% of OR personnels which included in the study had urine TFA more than maximum permission concentration of urine TFA (> 10 mg/g creatinine). The average concentration of urine TFA was 17.1945 mg/g creatinine. The concentration of halothane which was sampling from ORs revealed levels over exposure limit of halothane (> 0.5 ppm when used in combination with nitrous oxide). Recovery room had some trace gas of halothane but not over exposure limit.

After Division of Anesthesiology received that report. Halcthane was cancelled from ORs of Nakhonpathom Hospital and The Division of Anesthesiology started the project to improve ventilation of the ORs and planned to install scavenging system in the future.

The 2^nd  Collection of urine TFA was done at January 2006 (4 months after cancelled halothane from ORs). There were 38.78% of OR personels which had urine TFA more than maximum permission concentration. The average concentration of urine TFA was 9.3006 mg/g creatinine.