Results
Results of pilot study showed 93.7% success rate in ventilating manikins for hook method, compared to a 90% and 87.3% success rate for E/C and T/E methods respectively. No significant difference has been found between three methods.In patients ventilated by the hook method, 47.6% were women and 52.4% were men. The mean age of patients was 46 ± 17.4 with a minimum age of 18 years and maximum age of 99 years. In patients ventilated by the E/C technique, 48.2% of women and 51.8% of men. The mean age of patients in this group was 50 ± 18.8 with a minimum age of 18 and a maximum age of 99 years. In T/E method group 48.2% of patients were female and 51.8% were male. The mean age of patients in this group was 47 ± 17.6 with a minimum age of 18 and a maximum age of 89 years.There was no significant difference in terms of sex distribution between three groups (PV: 0.998). In comparison with PCO2 results obtained from capnography between E/C, T/E and Hook techniques, the ventilation rate was 87.2% and 89.6% in the T/E and E/C methods respectively and 93.3% in the Hook method. The success rate of ventilation with the Hook method was considerably higher than the E / C and T/E methods. There was a significant difference in ventilation success between the three methods (PV = 0.038).PCO2 measurement times from the 2nd to the 10th second were recorded in three techniques and a statistically significant difference was observed in fifth to eighth seconds (PV = 0.008), (PV < 0/001), (PV < 0/001) respectively.More information is shown in Table 
Comparison of capnograph-derived PCO2s in different measurements between ventilated patients with hook method, T/E method and E/C technique*IQR = InterQuartileRange** significant
Trend of Pco2 changes at measurement times by E / C, T/E and hook methods