Hana o ka Pulse oximetry

Hōʻike ka nānā ʻana o ke koko-oxygen i ka pākēneka o ke koko i hoʻopiha ʻia me ka oxygen.ʻOi aku ka kikoʻī, e ana ia i ka pākēneka o ka hemoglobin, ka protein i loko o ke koko e lawe ana i ka oxygen.ʻO nā pae maʻamau e ʻae ʻia no nā maʻi me ka ʻole o ka pulmonary pathology mai 95 a 99 pakeneka.No ka mea ma'i e hanu ana i ka ea lumi ma kahi a kokoke i ka ilikai, he kuhi no ka pO arterial₂Hiki ke hana ʻia mai ke koko-oxygen monitor "saturation of peripheral oxygen" (SpO₂) heluhelu.

Hoʻohana ka oximeter pulse maʻamau i ka mea hana uila a me ʻelua mau kukui uila liʻiliʻi (LED) e kū pono ana i kahi photodiode ma kahi ʻāpana translucent o ke kino o ka mea maʻi, maʻamau ka manamana lima a i ʻole ka pepeiao pepeiao.He ʻulaʻula hoʻokahi LED, me ka lōʻihi nalu o 660 nm, a ʻo kekahi he infrared me ka lōʻihi nalu o 940 nm.ʻOkoʻa loa ka ʻai ʻana o ka māmā ma kēia mau nalu nalu ma waena o ke koko i hoʻopiha ʻia me ka oxygen a me ke koko nele i ka oxygen.Hoʻomoʻa ʻia ka hemoglobin oxygen i nā kukui infrared hou aʻe a hiki i ke kukui ʻulaʻula ke hele.ʻO ka hemoglobin deoxygenated e hiki ai i nā kukui infrared ke hele a komo i nā kukui ʻulaʻula hou aʻe.Hoʻokaʻawale nā ​​LED ma o kā lākou pōʻai o kekahi, a laila ʻo kekahi, a laila ʻelua ma kahi o kanakolu manawa i kēlā me kēia kekona e hiki ai i ka photodiode ke pane i ke kukui ʻulaʻula a me ka infrared e hoʻokaʻawale a hoʻoponopono hoʻi no ka baseline kukui ambient.

Ana ʻia ka nui o ke kukui i hoʻouna ʻia (ma nā huaʻōlelo ʻē aʻe, ʻaʻole i komo ʻia) a hana ʻia nā hōʻailona maʻamau no kēlā me kēia nalu.Ke loli nei kēia mau hōʻailona i ka manawa no ka mea e piʻi ana ka nui o ke koko ʻaʻa i kēia manawa (ʻoiaʻiʻo pulses) me kēlā me kēia puʻuwai.Ma ka unuhi ʻana i ka liʻiliʻi liʻiliʻi i hoʻouna ʻia mai ke kukui i hoʻouna ʻia i kēlā me kēia nalu, ua hoʻoponopono ʻia nā hopena o nā ʻiʻo ʻē aʻe no, e hana ana i kahi hōʻailona mau no ke koko arterial pulsatile. ʻO ka ratio o ke ana kukui ʻulaʻula i ke ana kukui infrared a laila helu ʻia e ka mea hana. (e hōʻike ana i ka ratio o ka oxygenated hemoglobin i deoxygenated hemoglobin), a laila hoʻololi ʻia kēia ratio i SpO₂e ke kaʻina hana ma o ka papa ʻimi e pili ana i ke kānāwai Beer–Lambert.Hoʻohana ʻia ka hoʻokaʻawale hōʻailona i nā kumu ʻē aʻe: kahi plethysmograph waveform ("pleth wave") e hōʻike ana i ka hōʻailona pulsatile e hōʻike pinepine ʻia no ka ʻike maka o nā pulses a me ka maikaʻi o ka hōʻailona, ​​a me ka ratio helu ma waena o ka pulsatile a me ka baseline absorbance ("perfusion. index") hiki ke hoʻohana ʻia e loiloi i ka perfusion.