Abstract

Microbial contamination of air in the operating theatre (OT) is considered to be a risk factor for surgical site infections (SSI) and quality of air can be considered as a mirror of the hygienic condition of these rooms. This study intended to determine the bacterial load and antibiotic susceptibility pattern of isolates in OT indoor air of Hawassa University Referral Hospital. A cross sectional study was conducted to measure indoor air microbial quality of OT from November 2014 to January 2015.  120 indoor air samples were collected from six sites in ten rounds using purposive sampling technique by Settle Plate Method (Passive Air Sampling following 1/1/1 Schedule). Sample processing and antimicrobial susceptibility testing was done using standard microbiological methods. The mean bacterial load of major OT 85.6 and 8.6 CFU/dm2 were recorded at active and passive time respectively. Likewise, 387.05 and 375.3 CFU/dm2 were observed in sterilization room and sterilized material store respectively. The finding was under acceptable range based on standard set by Fisher.  Among the isolated five bacteria, S. aureus 54/120 (45%) and coagulase negative Staphylococci (CNS) 45/120 (37.5%) were the predominant species and highly resistant to penicillin and tetracycline (83.3 and 81.5%) respectively. Even though the overall mean CFU lied under the acceptable range, 65% of 120 samples were under the unsatisfactory level of bacterial load. The finding implies that the high bacterial load is a risk factor for surgical site infection (SSI).  Therefore to reduce the load of bacterial contamination at critical area as well in the hospital environments, the hospital infection prevention and patient safety (IPPS) should be improved.

Key words: Indoor air, hospital environment, Southern Ethiopia.