Transcutaneous monitoring of oxygen saturations is carried out using a device called a pulse oximeter. It is a simple, non-invasive test that can be used to estimate the amount of oxygenated haemoglobin in the blood. This monitoring can take place continuously, or on an intermittent basis. A probe is placed on a finger, toe, or earlobe. The probe contains a light source which transmits red and infrared wavelengths through a pulsating capillary bed. The light is transmitted through the tissue, and a photodetector on the other side measures the light which passes through. The monitoring unit analyses this, and works out the amount of light that has been absorbed by the oxygenated blood in the tissue. The amount of oxygenated blood is then displayed as a percentage saturation.<\/p>\r\n
Once you have watched this video, why not attempt the multiple choice quiz to test your knowledge?<\/p>\r\n","protected":false},"excerpt":{"rendered":"
Transcutaneous monitoring of oxygen saturations is carried out using a device called a pulse oximeter. It is a simple, non-invasive test that can be used to estimate the amount of oxygenated haemoglobin in the blood. This monitoring can take place continuously, or on an intermittent basis. A probe is placed on a finger, toe, or […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2,1],"tags":[],"class_list":["post-84","post","type-post","status-publish","format-standard","hentry","category-tomorrows-clinicians","category-uncategorized","entry"],"youtubeVideo":"436071555\/8aef380ccd","question1":"How does the pulse oximeter device measure oxygen saturation?","answers1":"Calculates the oxygen saturation using a laser| Calculates the proportion of red\/infrared light absorbed by oxygenated haemoglobin| Calculates the partial pressure of oxygen and carbon dioxide| Calculates the pulse rate to determine the oxygen saturation\r\n","correctAnswer1":"1","correctAnswerText1":"The differing absorption of red and infra-red light by oxygenated and deoxygenated haemoglobin is used to calculate the oxygen saturation, the probe is also dependent on pulsitile flow to determine an accurate arterial oxygen saturation.","question2":"What steps should be taken before placing the pulse oximeter probe on the patient?","answers2":"Clean the probe| Check the pulse to, and the warmth and colour of, the extremity to be used| Remove any nail varnish or false nails| All of the above.\r\n","correctAnswer2":"3","correctAnswerText2":"Cleaning the probe not only reduces risk of cross contamination from patient but clears any smudges or dirt that may interfere with light absorption, nail varnish or false nail can interfere with light absorption giving an inaccurate reading. Check for reduced\/absent pulse and for signs of vasoconstriction as this can affect the accuracy of the reading.","question3":"Where can transcutaneous oxygen saturations be performed?","answers3":"Toes| Fingers| Ear lobes| All of the above","correctAnswerText3":"Trancutanous oxygen saturations can be taken at the digits of the upper or lower limbs and the earlobes providing the correct pulse oximetery probe is used (modified probes are required for the earlobe).","correctAnswer3":"3","question4":"Which of these can cause pulse oximetery artifact?","answers4":"Cannula in situ| Measuring oxygen saturations at the toes| Shivering| Chest drain\r\n","correctAnswer4":"2","correctAnswerText4":"Shivering can cause an artifact, ensure the patient is kept warm.","question5":"What other vital sign does the pulse oximeter measure?","answers5":"Heart rate| Pulse rate| Pulse rhythm| Carbon dioxide levels\r\n","correctAnswer5":"1","correctAnswerText5":"","question6":"Typically, what is the acceptable range of oxygen saturations?","answers6":"88%-92%| >94%| 92%-94%| 90%-92%","correctAnswer6":"1","correctAnswerText6":"","question7":"If the oxygen saturation is unrecordable what is the next most appropriate step?","answers7":"Try another site| Call the medical emergency team| Change the pulse oximeter probe| Try it on yourself.\r\n","correctAnswer7":"0","correctAnswerText7":"First try another site, if this fails trying the probe on yourself or changing the probe\/device may be appropriate.","question8":"What should be done if the oxygen saturation falls below the target range for a patient?","answers8":"Assess the patient| Give\/increase oxygen| Call for medical assistance| All of the above","correctAnswer8":"3","correctAnswerText8":"Clinically assess the patient to identify if there is any clinical deterioration and what the cause is, giving oxygen is an appropriate initial management strategy. However it is most important to remain with the limits of your competence and ask for help by calling for assistance immediately.","question9":"If the oxygen saturation is low for the patient or unrecordable what is the next most appropriate investigation?","answers9":"Spirometry| Peak flow rate| Arterial blood gas| Chest x-ray","correctAnswer9":"2","correctAnswerText9":"Amongst other things, an arterial blood gas measures the oxygen saturation and partial pressures of oxygen and carbon dioxide in the blood, assessing the severity of hypoxia and\/or carbon dioxide retention.","question10":"Where should the oxygen saturations be documented and what else should be recorded?","answers10":"Observation chart with inspired percentage of oxygen if being administered| Medical notes with respiratory rate| Observation chart with haemoglobin| Medical notes with inspired % oxygen\/air","correctAnswer10":"0","correctAnswerText10":"Oxygen saturations should always be documented on the observation chart with the other vital signs, whether the patient was on air or supplementary oxygen should also be recorded. This allows all vitals and trends to be reviewed give a more complete clinical picture and the oxygen saturation to be put in context of the inspired oxygen respectively.","question11":"","answers11":"","correctAnswer11":"","correctAnswerText11":"","question12":"","answers12":"","correctAnswer12":"","correctAnswerText12":"","question13":"","answers13":"","correctAnswer13":"","correctAnswerText13":"","question14":"","answers14":"","correctAnswer14":"","correctAnswerText14":"","question15":"","answers15":"","correctAnswer15":"","correctAnswerText15":"","icon":"oxygen-therapy","parentId":"","recapId":"432","_links":{"self":[{"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/84"}],"collection":[{"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=84"}],"version-history":[{"count":7,"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/84\/revisions"}],"predecessor-version":[{"id":811,"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/84\/revisions\/811"}],"wp:attachment":[{"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=84"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=84"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=84"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}