Contamination of equipment and surfaces in the operating room anesthesia workspace: a cross-sectional study

ABSTRACT BACKGROUND: Contamination of the breathing circuit and medication preparation surface of an anesthesia machine can increase the risk of cross-infection. OBJECTIVE: To evaluate the contamination of the anesthetic medication preparation surface, respiratory circuits, and devices used in general anesthesia with assisted mechanical ventilation. DESIGN AND SETTING: Cross-sectional, quantitative study conducted at the surgical center of a philanthropic hospital, of medium complexity located in the municipality of Três Lagoas, in the eastern region of the State of Mato Grosso do Sul. METHODS: Eighty-two microbiological samples were collected from the breathing circuits. After repeating the samples in different culture media, 328 analyses were performed. RESULTS: A higher occurrence of E. coli, Enterobacter spp., Pseudomonas spp., Staphylococcus aureus, and Streptococcus pneumoniae (P < 0.001) were observed. Variations were observed depending on the culture medium and sample collection site. CONCLUSION: The study findings underscore the inadequate disinfection of the inspiratory and expiratory branches, highlighting the importance of stringent cleaning and disinfection of high-touch surfaces.

A comparative evaluation of humidifier with heated wire breathing circuit under general anesthesia / 대한마취과학회지

BACKGROUND: Dry and cold anesthetic gas deteriorates patient's respiratory function and body heat balance. We examined whether a humidifier with heated wire circuit might maintain core temperature and humidity of inspired gas in patient undergoing general anesthesia. METHODS: We enrolled forty ASA physical status I, II patients under general anesthesia for this study. We allocated the patients randomly into two groups with (experimental group) or without (control group) Humitube(R) anesthesia circuit, which delivered heated and humidified inspired anesthetic gases. We recorded the temperatures and humidity of the inspired gases throughout the surgery. RESULTS: The temperatures and relative humidity of the inspired gases in experimental group were significantly greater compared to control group (36.2 +/- 0.9degrees C, 89.5 +/- 4.8% vs. 30.4 +/- 1.8degrees C, 37.9 +/- 5.9%, P < 0.05) during anesthesia. The core temperatures in experimental group were significantly greater compared to control group (36.1 +/- 0.3degrees C vs. 35.7 +/- 0.1degrees C, P < 0.05) during anesthesia. CONCLUSIONS: A humidifier with heated wire system for anesthesia breathing circuit is helpful to maintain core temperature and adequate humidity.

Obstruction of Airway Filter/Heat and Moisture Exchanger during Cardiac Surgery: A case report / 대한마취과학회지

An acute obstruction of the breathing circuit during surgery can be a devastating situation. A 45-year old man who diagnosed with infective endocarditis and aortic valve regurgitation underwent emergency cardiac surgery. However, an obstruction of the breathing circuit occurred when the cardiopulmonary bypass was weaned. Fortunately, the ventilation normalized after removing the airway filter/heat and moisture exchanger (HME). We report this case of a HME obstruction of the breathing circuit with a review of the relevant literature.

Obstruction of the Scavenging Pathway during Surgery: A case report / 대한마취과학회지

An acute obstruction of the breathing circuit can be devastating situation. An 56-year old man who was diagnosed distal femur fracture underwent open reduction with internal fixation. During surgery, an obstruction of the breathing circuit occurred and we found the cause of obstruction was the plugging of a gas disposal tube with ice and dust accumulation. After removing the ice and dust, ventilation normalized. We report this case of an obstruction of the scavenging pathway with a review of the relevant literature.

Pathogens Isolated from Breathing Circuit in Mechanical Ventilation Patients: Analysis and Nursing Intervention / 中华医院感染学杂志

OBJECTIVE To investigate the breathing circuit bacteria and the lower respiratory airway bacteria(LRAB) isolated from mechanical ventilation patient. METHODS A total of 48 strains of the breathing circuit and 87 strains of LRAB from mechanical ventilation patients were analyzed. RESULTS The main organism in the breathing circuit were Pseudomonas aeruginosa(31.2%),and Stenotrophomonas maltophilia(27.2%).The main organisms in LRAB were P.aeruginosa(37.9%),Klebsiella pneumoniae(17.3%) and Candida albicans(13.7%).The pathogens of the breathing circuit were 73.3 % similar with those of LRAB. CONCLUSIONS To control infection effectively,effective sterilizing measures must be carried out,especially attention to sterilizing and managements of the breathing circuit.

The Effect of Intratracheal Nebulized Lidocaine and Intravenous Lidocaine on the Cardiovascular Stimulating Response to Tracheal Intubation / 대한마취과학회지

BACKGROUND: Hypertension and tachycardia usually accompany laryngoscopy and tracheal intubation. Topical and intravenous lidocaine are used in an attempt to blunt these potentially adverse hemodynamic responses, but these effects of lidocaine are controversial. The purpose of this study is to evaluate whether intratracheal nebulized lidocaine and/or intravenous lidocaine attenuate circulatory stimulating response to tracheal intubation. METHODS: Sixty patients, ASA physical status I, scheduled elective surgery, were randomly assigned to receive a preintubation dose of either 5 mL of normal saline intravenously, 4 mL of 4% lidocaine by intratracheal nebulizer, 1.5 mg/kg of 2% lidocaine intravenously, or 4 mL of 4% lidocaine intratracheal nebulizer and 2% lidocaine of 1.5 mg/kg intravenouly. Induction of anesthesia was accomplished with 5 mg/kg of thiopental IV, and 1 mg/kg of succinylcholine was given. Laryngoscopy and intubation was performed, and anesthesia maintained with 2% enflurane in 50% nitrous oxide in oxygen. Blood pressure and heart rate were recorded at preinduction, after induction, and every minute until 5 min after intubation. RESULTS: Intratracheal nebulized lidocaine and/or intravenous lidocaine were effective in attenuating increases in systolic pressure with no detectable difference between them, and failed to attenuate increases in diastolic pressure and heart rate. And significant decrease in systolic pressure 3 min after intubation was detected in intratracheal and intravenous lidocaine group. CONCLUSIONS: These data suggest that intratracheal nebulized lidocaine or intravenous lidocaine is effective in attenuating increase in systolic pressure to tracheal intubation, but intratracheal and intravenous lidocaine has not synergistic effect.