بررسي دقت تخمين فشار CO2 خون شرياني از فشار CO2 انتهاي بازدمي در سه شدت تمريني 30، 50 و 70 درصد حداكثر اكسيژن مصرفي

Survey of Accuracy of Arterial CO2 Pressure Estimation From End Tidal CO2 Pressure at Three Exercise Intensities of 30, 50 and 70 Percentage of VO2max

ﺳﺎﺑﻘﻪ و ﻫﺪف: ﻫﺪف ﺗﺤﻘﯿﻖ ﺣﺎﺿﺮ ﺑﺮرﺳﯽ ﺗﺎﺛﯿﺮ ﺷﺪت ﺗﻤﺮﯾﻦ ﺑﺮ دﻗﺖ ﺗﺨﻤﯿﻦ ﻓﺸﺎر CO2 ﺧﻮن ﺷﺮﯾﺎﻧﯽ از ﻓﺸﺎر CO2 اﻧﺘﻬﺎي ﺑﺎزدﻣﯽ ﺑﻮد. ﻣﻮاد و روش ﻫﺎ: 10 آزﻣﻮدﻧﯽ ﺑﻪ ﻋﻨﻮان ﻧﻤﻮﻧﻪ اﻧﺘﺨﺎب ﺷـﺪﻧﺪ. اﺑﺘﺪا ﺣﺪاﮐﺜﺮ اﮐﺴﯿﮋن ﻣﺼﺮﻓﯽ )VO2max( آزﻣﻮدﻧﯽ ﻫﺎ ﺑﺎ اﻧﺠﺎم ﭘﺮوﺗﮑﻞ ﺗﻤﺮﯾﻨﯽ ﻓﺰاﯾﻨﺪه ﺑﺪﺳـﺖ آﻣﺪ. ﺳﭙﺲ ﻫﺮ آزﻣﻮدﻧﯽ ﺳﻪ ﭘﺮوﺗﮑﻞ ﺗﻤﺮﯾﻨﯽ را ﺑﺎ ﺳﻪ ﺷﺪت 30 ، 50 و 70 درﺻﺪ VO2max ﺧﻮد ﮐﻪ ﻣﺪت زﻣﺎن ﻫﺮ ﺗﻤﺮﯾﻦ 12 دﻗﯿﻘﻪ ﺑﻮد اﻧﺠﺎم داد. ﻧﻤﻮﻧﻪ ﻫﺎي ﺧﻮﻧﯽ در ﺣﯿﻦ اﺳﺘﺮاﺣﺖ، ﺗﻤﺮﯾﻦ و دوره رﯾﮑﺎوري ﮔﺮﻓﺘﻪ ﺷﺪ و ﻫﻤﭽﻨﯿﻦ داده ﻫﺎي ﻣﺮﺑﻮط ﺑﻪ ﮔﺎزﻫﺎي ﺗﻨﻔﺴﯽ ﺟﻤﻊ آوري ﺷﺪﻧﺪ. ﯾﺎﻓﺘﻪ ﻫﺎ: ﺿـﺮﯾﺐ ﻫﻤﺒﺴﺘﮕﯽ ﺑﯿﻦ PaCO2 و PaCO2pre و ﻣﻘﺪار p در ﺗﻤﺮﯾﻦ ﺑﺎ ﺷﺪت 30 درﺻﺪ ﺑﻪ ﺗﺮﺗﯿﺐ 0/807=r و 0/001=p و در ﺗﻤﺮﯾﻦ ﺑﺎ ﺷـﺪت 50 درﺻـﺪ 0/822=r و 0/001=p و در ﺷــﺪت 70 درﺻـﺪ VO2max ﺑﺮاﺑﺮ ﺑﺎ 0/552=r و 0/003=p ﺑﻮد. درﺻــﺪ ﺧﻄﺎي ﺗﺨﻤﯿﻦ در ﺷﺪت 70 درﺻﺪ VO2max ﺑﺎﻻﺗﺮ از درﺻﺪ ﺧﻄﺎ در ﺷﺪت ﻫﺎي 30 و 50 درﺻﺪ VO2max ﺑﻮد. نتيجه گيري: بر اساس يافته هاي اين مطالعه بنظر مي رسد دقت تخمين فشار CO2 خون شرياني از فشار CO2 انتهاي بازدمي در شدت‌هاي تمريني بالاتر نسبت به شدت هاي پايين تر كمتر است

Background & Purpose: The aim of this study was investigation of the effect of exercise intensity on accuracy of arterial CO2 pressure estimation from end tidal CO2 pressure. Methodology: Ten subjects were selected as samples. At first, the maximum oxygen consumption (VO2max) of each subject was obtained by performing progressive exercise protocol. Then, each subject performed three protocols with intensities of 30%, 50% and 70% of his own VO2max and duration of each exercise was 12-minute. Blood samples were taken during the rest, exercise and recovery periods, and data on respiratory gases were collected. Results: Correlation coefficient between PaCO2 and PaCO2pre and P value in exercise with intensities of 30%, 50% and 70% of VO2max were r = 0.807, P=0.001; r=0.822, P= 0.001 and r = 0.552, P= 0.003 respectively. The percentage of estimation error was higher in the intensity of 70% of VO2max than intensities of 30% and 50% of VO2max. Conclusion: Based on the findings of this study, it seems that the accuracy of prediction of arterial CO2 pressure from end tidal CO2 pressure is lower in high intensities exercise than low intensities exercise.