EFFECT OF REPEATED EXPOSURE TO SUBANESTHETIC DOSES OF SEVOFLURANE ON LUNG HISTOLOGY: AN EXPERIMENTAL STUDY ON ALBINO RAT
Nagla Mohamed Salama1, Abla Abdel Rahman Ali2, Sherine Mostafa Amin3, Nesrine Abdel-Rahman El-Refai3 and Nahla Abdel Fattah AlKady3
Departments of1Histology, 2Forensic Medicine and Clinical Toxicology and 3Anesthesia,
Faculty of Medicine, Cairo University
The use of sevoflurane in open circuit anesthesia has been established in many countries throughout the world. The present work was designed to determine whether repeated exposure to subanesthetic doses of sevoflurane, similar to that occurring to operating theatre staff when open circuits are used, could have harmful effect on the lung. The study was done on forty rats divided into two groups: group 1 involved 10 rats considered as control group and group 2 involved 30 rats exposed to subanesthetic concentration of sevoflurane (40 ppm) 2 hours daily for one month. The lungs of the rats exposed to sevoflurane showed infiltration of the bronchioles, alveoli and interalveolar septa with inflammatory cells. There were areas of emphysema alternating with areas of alveolar collapse (atelectasis). Vascular congestion, perivascular & alveolar edema and proliferation of type II pneumocytes were also evident. There was significant decrease in the lung content of elastic fibers and significant increase in collagen fibers (fibrosis). It was concluded that repeated exposure to subanesthetic doses of sevoflurane resulted in development of many pulmonary lesions.