Journal of Korean Society of Spine Surgery Digital Pulse Oximetry for the Screeing of Lower Extremity Arterial Disease Dae Moo Shim, M.D., Sung Kyun Oh, M.D., Jung Nam Kwon, M.D. J Korean Soc Spine Surg 2014 Mar;21(1):36-40. Originally published online March 31, 2014; http://dx.doi.org/10.4184/jkss.2014.21.1.36 Korean Society of Spine Surgery Department of Orthopedic Surgery, Inha University School of Medicine #7-206, 3rd ST. Sinheung-Dong, Jung-Gu, Incheon, 400-711, Korea Tel: 82-32-890-3044 Fax: 82-32-890-3467 Copyright 2014 Korean Society of Spine Surgery pissn 2093-4378 eissn 2093-4386 The online version of this article, along with updated information and services, is located on the World Wide Web at: http:///doix.php?id=10.4184/jkss.2014.21.1.36 This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Original Article pissn 2093-4378 eissn 2093-4386 J Korean Soc Spine Surg. 2014 Mar;21(1):36-40. http://dx.doi.org/10.4184/jkss.2014.21.1.36 Digital Pulse Oximetry for the Screeing of Lower Extremity Arterial Disease Dae Moo Shim, M.D., Sung Kyun Oh, M.D., Jung Nam Kwon, M.D.* Department of Orthopedic Surgery,School of Medicine, Wonkwang University, Iksan, Korea Division of Vascular Surgery, School of Medicine, Wonwang University, Gunpo, Korea* Institute of Wonkwang Medical Science. Iksan, Korea Study Design: Retrospective study. Objectives: The aim of the study was to investigate the usefulness of a handheld digital pulse oximetry in the detection of lower extremity arterial disease. Summary of Literature Review: Pulse oximetry is a well-established method for noninvasive evaluation of arterial oxygenation. Materials and Methods: A Retrospective study was performed in 45 patients with lower extremity arterial disease. We compared the accuracy of a handheld digital pulse oximetry and the ankle brachial index (ABI). Digital pulse oximetry was conducted for 42 patients with 84 limbs to measure the SaO2 of their index fingers and big toes in supine position. The ABI was defined as abnormal if it was less than 0.9. Pulse oximetry of big toes was defined as abnormal if the SPO2 was less than 96% or it was more than 2% lower than that of the index finger. Results: Digital pulse oximetry had a sensitivity of 47%(95% CI, 34-60%) and specificity of 86%(95% CI, 64-96%). ABI had a sensitivity of 49%(95% CI, 34-64%) and specificity of 95%(95% CI, 72-99%). Positive predictive values were 91%(95% CI, 74-98%) for digital pulse oximetry and 96%(95% CI, 77-99%) for ABI. Negative predictive values were 37%(95% CI, 24-51%) for digitial pulse oximetry and 43%(95% CI, 25-72%) for ABI. In 22 cases with acute ischemicwere the sensitivity 73%, the specifity 100%, the positive predictive value 100% and the negative predictive value 79%. Conclusions: Handheld digital pulse oximetry of the big toes seems as accurate as ABI to detect lower extremity arterial diseases. The combination of both will help to distinguish low extremity arterial disease and spinal radiculopathy. Key Words: arterial disease, pulse oximetry, ankle brachial index 서론 파행이나하지방사통을호소하는환자에서혈관성파행과신경학적파행을감별하는것은쉽지않다. 1) 특히고령의환자에서증상과이학적검사만으로혈관성파행을배제하는것은객관적검사를시행하기전에는쉽지않으며혈관조영술같은침습적인검사를고려할수밖에없다. 1,2) 외래진료실이나응급실에서짧은시간안에간편하게검사할수있는검사로는족배동맥의촉진이나상완과발목의혈압을측정하는 ABI 검사가있다. 그러나족배동맥의촉진의경우관찰자내오차의범위도크고 3) 선천적으로족배동맥이존재하지않는경우도 4-12% 에이르고있으며양성예측도가 49% 에불과하다는보고도있다. 2-5) 또한 ABI 역시비침습적이고경제적이어서동맥질환의검사시널리사용되고있으나검사를타진료과에의뢰해야하는번거로움과즉시결과를확인할수없는단점이있고검사의정확도에대해서도논란이있다. 5) Joyce 등 6) 은말초동맥폐쇄질환시허혈성하지는의미있게낮은산소포화도를보이므로비침습적인방법으 로산소포화도측정이쓰일수있다고보고하였다. 이에본저자는혈관내산소포화도를측정하거나술후혈관 개방성평가시쓰이는디지털맥박산소포화도검사를무지에서 Received: January 15, 2013 Revised: February 26, 2013 Accepted: November 28, 2013 Published Online: March 31, 2014 Corresponding author: Sung Kyun Oh, M.D. Department of Orthopedic Surgery, School of Medicine, Wonkwang University Sanbon Hospital, Sanbondong, Gunpo city, Gyeongido, Korea TEL: 82-31-390-2992, FAX: 82-31-390-2244 E-mail: niceo@hanmail.net This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. This paper was supported by Wonkwang univeristy in 2014. 36 Copyright 2014 Korean Society of Spine Surgery
Journal of Korean Society of Spine Surgery Handheld Digital Pulse Oximetry 시행하여하지통증을호소하는환자에서하지혈관성파행을야기하는하지동맥질환의진단을위해쓰일수있는지평가하고자하였다. 대상및방법 본연구의대상은 2009년 8월부터 2010년 8월까지하지통증을주소로내원하여 3차원 CT (computed tomography) 혈관조영술을통해하지동맥의협착과폐쇄로진단된 45명의환자를대상으로하였으며하지말초동맥질환의진단은임상증상과 CT 혈관조영술을통해의의있는동맥협착과폐쇄가동반된경우혈관외과전문의가진단하였다. 환자들의평균나이는 67세, 남자는 35명, 여성 10명이었다. 이중동맥경화에의한일측폐쇄가 40명, 버거씨병이 3명, 당뇨병성혈관병증에의한경우가 2명이었다. 또한색전증이나혈전에의한급성동맥폐쇄로진단된경우는 11명이었다 (Table 1). SpO 2 의측정은휴대용 Radical-7 Signal Extraction Pulse Oximeter (Masimo Co., Irvine, CA, USA) 를이용해수부의인지와족부의양무지에서측정하였고환자는앙와위에서측정하도록하였다 (Fig. 1). 무지의결손이나괴사등으로측정이불가한경우는제 2족지에서측정하였다. ABI의측정은 Non-invasive Vascular Screening Device VP-1000 (Model BP 230 PRE 2, OMRON Healthcare Co., Kyoto, Japan) 를이용하였다. ABI 경우 0.9 미만인경우를양성으로정의하였고, 무지산소포화도의경우수지와 2% 이상차이를보이거나절대값이 96% 이하인경우를양성으로정의하였다. 5-10) 통계학적인분석은 SPSS ver. 12(SPSS Inc.,Chicago,IL,USA) 을이용하여 receiver operating characteristic (ROC) 커브를측정하여 ABI와산소포화도검사를비교하였고, 각검사의민감도, 특이도, 양성예측도, 음성예측도를 Clinical Calculater (Vassar Stat.NY, USA) 를이용하여계산하였다. 결과 45명의환자중 42명 84예의하지에서휴대용디지털산소포화도측정기를통해수부와무지에서산소포화도측정을하였고, 33명 66예의환자에서 ABI 측정값을얻었다. 이를통해각각의검사의민감도, 특이도, 양성예측도, 음성예측도를계산하였다 (Table 2). ROC curve의경우산소포화도측정기의아래면적은 0.321(95% CI, 0.205-0.438), ABI의경우 0.375(95% CI, 0.246-0.505) 를보였다 (Fig. 2). 급성동맥폐쇄로진단되었던 11명 22 예의하지에서의산소포화도측정의민감도는 73%(95% CI, 37-93%), 특이도는 100%(95% CI, 68-100%), 양성예측도는 Table 1. Demography of patients. Number of Patients(limbs) 45 (90 limbs) Average Age (yr) 66.9(40-92) DM,n (%) 31(69%) Hypertension,n(%) 32(71%) Known heart disease,n(%) 11(24%) Treatment option Surgery 28(62%) Conservative 17(38%) Fig 1. Handheld digital pulse oximetry. Table 2. Results for Pulse oximetry test, Ankle brachial index. Test Results Arterial disease Present No.(%) Arterial disease Absent No.(%) Sensitivity (95% CI), % Specificity (95% CI), % Positive Predictive Value(95% CI), % Negative Predictive Value(95% CI), % Pulse oximetry test 47(34-60) 86(64-96) 91(74-98) 37(24-51) Positive 29(35) 3(4) Negative 33(39) 19(23) ABI 49(34-64) 95(72-99) 96(77-990 43(28-72) <0.9 23(35) 1(2) 0.9 24(36) 18(27) CI ;confidence interval ABI ; ankle brachial index 37
Dae Moo Shim et al Volume 21 Number 1 March 2014 ROC 곡선 ROC 곡선 1- 특이도 대각세그먼트는동물에의해생성됩니다. 1- 특이도 대각세그먼트는동물에의해생성됩니다. Fig 2. Receiver operating characteristic (ROC) curve for the pulse oximetry test and the ankle brachilaindex(abi). (A) ROC curve for pulse oximetry test, Area under the curve was 0.321 (95% confidence interval:0.205-0.438,p<0.014). (B) ROC curve for ABI,Area under the curve was 0.375 (95% confidence interval:0.246-0.505,p<0.114). 100%(95% CI, 60-100%), 음성예측도는 79%(95% CI, 49-94%) 였고, 이중 4명 8예의하지에서 ABI를측정할수있었고이들의민감도는 60%(95% CI, 17-90%), 특이도는 100%(95% CI, 31-100%), 양성예측도는 100%(95% CI, 31-100%), 음성예측도는 60%(95% CI, 17-93%) 였다. 고찰 하지동맥질환의경우하지허혈을유발하여하지통증을일으킨다는점에서척추질환과유사하지만이들두질환의임상적감별은쉽지않다. 특히, 혈관성파행과신경학적파행의감별점으로제시되는허리를구부리거나앉은자세에서호전되는신경학적파행의특징역시혈관성파행에서도호전되는경우가있어자세변화와연관된통증역시큰구별점은될수없다. 1,2) 또한척추관협착증의경우하지직거상검사혹은신경학적인이학적검사에서정상인경우가흔하고대부분고령의환자로허리의 퇴행성병변이동반되어있어동반된요통의유무역시혈관성파행과의감별에큰도움을주지못한다. 1,2) 또한족배동맥이나슬와동맥의촉진역시주관적인감각에의존해야하고동맥의기형이나없는환자도 12% 에이른다는보고도있어이역시객관화할수없는한계점이있다. 3) 또한하지동맥폐쇄에의한일측하지통증의경우역시추간판탈출증이나추간공협착증혹은탈출에의한증상과유사해감별을위해요추부위의자기공명검사를시행하게되는경우도흔히있다. 하지만하지동맥패쇄에의한통증의경우진단을위해시간이지연된경우비가역적손상으로인해하지절단으로이어질수있으며혈관성파행을신경학적인파행으로오인하여척추부위를수술한경우역시환자나의사에게돌이킬수없는후유증을남길수있다. 혈관질환에의한하지통증의경우임상에서권장되는선별검사의경우 ABI 나도플러초음파검사가있으나초음파검사의경우검사자의능력과기술이요구되며비용적인면에서도선별검사로는적절치않다. 7-9) ABI의경우비침습적이고경제적이어 38
Journal of Korean Society of Spine Surgery Handheld Digital Pulse Oximetry 서최근에는선별검사로추천되는방법이지만민감도와특이도가 90% 에이른다는보고에서부터무증상의환자에서는민감도가 28.4% 에불과하다는보고도있다. 7,10) 특히당뇨가있는환자의경우말초동맥의석회화로인해 ABI 를상승시킬수있으므로당뇨환자에서의 ABI 의정확도에우려를나타내는보고도있다. 11,12) 본연구와유사하게하지동맥허혈정도를산소포화도측정기를이용해평가하여하지동맥질환의선별검사로써의유용성을제시한보고도있으며이들의민감도와특이도는 77% 와 97% 로본연구보다높게나타났다. 13) 이연구의경우수지보다족무지에서 2% 이상낮게측정되는것이외에하지거상시 2% 이상감소되었을때에도양성으로정의하였다. 그러나본연구에서는당뇨환자의비율이 31% 로낮아모두당뇨환자였던연구보다민감도와특이도가감소한것으로보인다. 이는당뇨환자에서중심및말초에걸쳐전반적인혈관의협착이초래된당뇨병에의한혈관병증의경우에서더욱더피하산소포화도측정이도움이될수도있음을시사한다. 하지만본연구에서족무지산소포화도측정의경우민감도와특이도가 47% 와 86% 를보여선별검사로써의유용성은떨어진다고판단된다. 하지만본연구에서의 ABI 역시무지산소포화도측정과유사한민감도와특이도를보여이역시선별검사로서의유용성역시높지않았다. 디지털맥박산소포화도측정기의경우말초혈액내의헤모글로빈의산소포화도를측정하게되므로하지의혈류가감소되면산소포화도역시감소하게된다. 이원리를이용하여 Jawahar 등 8) 이말초혈관질환에서진단적가치를연구하였으나 ABI가 0.5미만의심한혈관질환을가진환자에서약 54% 만이양성소견을보였고 30 cm 이상하지거상시에추가적으로 23% 에서양성소견을보였다고하였으나이역시선별검사로서의유용성은낮다는결론을얻었다. 특히이연구에서산소포화도측정시혈관질환이있는환자에서측정이되지않는결측값도의미있는값으로볼수있다는주장을하였다. 실제본연구의실행시환자의중증도에따라산소포화도의값이비례하여감소하지않았으며다만색전증으로인해후경골동맥이폐쇄된증례들의경우 84%, 70% 의무지산소포화도를보인예가있었으나이이하의값을보인경우는없었다. 심한하지폐쇄라하더라도 70% 이하의산소포화도의경우측정이되지않으므로이역시의미있는값으로처리하여비정상으로보게되면무지산소포화도측정의민감도는증가할수있으며또한앙아위에서측정후 30 cm 이상하지를거상한후측정하는방법이나보행후파행증세가생겼을때산소포화도를측정하는방법역시민감도를증가시킬수있는방법으로사료된다. 본연구의한계점으로는증례수가비교적많지않고수술환자부터대증치료를시행한환자까지포함되어중증도가비균질한 단점이있으나하지동통을호소하는환자에서의족무지에서산소포화도측정이 ABI와유사한정도의진단정확도를보였다는것을보여주는데있다고하겠다. 또한휴대용으로간편하게외래나응급실에서단시간내에비침습적으로행할수있는검사라는장점이있으므로정형외과영역에서하지동맥질환의감별을위해시행될수있는또하나는진단술기로써도움이될것으로사료된다. 또한 ABI의경우정형외과전공의나전문의가아닌의료보조기사에의해행해지는병원이많고검사를의뢰해야하는번거로움을고려한다면 ABI와유사한정도의진단율을가진검사를외래나응급실에서할수있는점에서도움이크다하겠다. 또한급성동맥폐쇄에서무지산소포화도검사의민감도와특이도가높았던것은만성폐쇄보다측부혈관의발달이없었기때문으로사료되며 ABI 경우측정례가 8예로많치않아통계적의의를둘수는없었다. 다만급성동맥폐쇄에서공통적으로보였던차가운발은족배동맥의촉지이상으로의의가있고도움이될수있는이학적소견으로사료되었다. 결론 휴대용디지털맥박산소포화도측정기를이용한무지의산소포화도측정은선별검사방법으로는적합하지않지만하지동맥질환의진단에있어 ABI와유사한정확도를보인다. 무지의산소포화도측정은간편하고비침습적으로행할수있으므로정형외과외래나응급실에서혈관성파행의감별을위해보조적으로쓰일수있을것으로생각된다. REFERENCES 1. Chae IJ. Lumbar spinal stenosis. J Korean Soc Spine Surg.1999;6:220-7. 2. Lee HM. Pathophysiology of Lumbar Spinal stenosis. JKorean Soc Spine Surg.2000;7:100-5. 3. Brearley S, Shearman CP, Simms MH. Peripheral pulse palpation: an unreliable physical sign. Ann R Coll Surg Engl. 1992;74:169-71. 4. Barnhorst DA, Barner HB.Prevalence of congenitally absent pedal pulses. N Engl J Med.1968;278:264-5. 5. Criqui MH, Fronek A, Klauber MR, Barrett-Connor E, Gabriel S. The sensitivity, specificity, and predictive value of traditional clinical evaluation of peripheral arterial disease: results from noninvasive testing in a defined population. Circulation.1985;71:516-22. 39
Dae Moo Shim et al Volume 21 Number 1 March 2014 6. Joyce WP, Walsh K, Gough DB, Gorey TF, Fitzpatrick JM. Pulse oximetry: a new non-invasive assessment of peripheral arterial occlusive disease. Br J Surg.1990;77:1115-7. 7. Feigelson HS, Criqui MH, Fronek A, Langer RD, Molgaard CA. Screening for peripheral arterial disease: the sensitivity, specificity, and predictive value of noninvasive tests in a defined population. Am J Epidemiol.1994;140:526-34. 8. Jawahar D, Rachamalla HR, Rafalowski A, Ilkhani R, Bharathan T, Anandarao N. Pulse oximetry in the evaluation of peripheral vascular disease. Angiology.1997;48:721-4. 9. Johansson KE, Marklund BR,Fowelin JH. Evaluation of a new screening method for detecting peripheral arterial disease in a primary health care population of patients with diabetes mellitus. Diabet Med.2002;19:307-10. 10. Ouriel K, McDonnell AE, Metz CE, Zarins CK. Critical evaluation of stress testing in the diagnosis of peripheral vascular disease. Surgery.1982;91:686-93. 11. Hauser CJ, Klein SR, Mehringer CM, Appel P, Shoemaker WC. Assessment of perfusion in the diabetic foot by regional transcutaneous oximetry. Diabetes.1984;33:527-31. 12. Maser RE, Wolfson SK, Jr., Ellis D, et al. Cardiovascular disease and arterial calcification in insulin-dependent diabetes mellitus: interrelations and risk factor profiles. Pittsburgh Epidemiology of Diabetes Complications Study-V. Arterioscler Thromb.1991;11:958-65. 13. Parameswaran GI, Brand K, Dolan J. Pulse oximetry as a potential screening tool for lower extremity arterial disease in asymptomatic patients with diabetes mellitus. Arch Intern Med.2005;165:442-6. 휴대용디지털맥박산소포화도측정기를이용한하지동맥질환의진단 심대무 오성균 권정남원광대학교정형외과학교실 연구계획 : 후향적연구 목적 : 하지말초동맥질환과요추부방사통과의감별을위한검사로써휴대용디지털맥박산소포화도검사의유용성에대해서알아보고자하였다. 선행논문의요약 : 맥박산소포화도검사는동맥의산소포화도를비침습적으로검사할수있어선천성심장질환이나허혈성하지동맥질환의선별검 사에쓰일수있다. 대상및방법 : 2009 년 8 월에서 2010 년 8 월까지하지동맥질환으로확진된 45 명의양측하지를대상으로양측족부의무지에서맥박산소포화도와 ankle brachial index (ABI) 를측정하였고, 이들값을후향적으로조사하여민감도, 특이도, 양성예측도, 음성예측도를계산하였다. ABI 의경우 0.9 미만 인경우를양성으로정의하였고, 무지산소포화도의경우수지와 2% 이상차이를보이거나 96% 이하인경우를양성으로정의하였다. 결과 : 45 명의환자중 42 명 84 예의하지에서맥박산소포화도를측정하였고, 33 명 66 예의하지에서 ABI 의측정값을얻었다. 디지털맥박산소포화도 검사의경우민감도는 47%(95% CI, confidence interval 34-60%), 특이도는 86%(95% CI, 64-96%), 양성예측도는 91%(95% CI, 74-98%), 음성예측도 는 37%(95% CI, 24-51%) 였다. ABI 의경우민감도는 49%(95% CI, 34-64%), 특이도는 95%(95% CI, 72-99%), 양성예측도는 96%(95% CI, 77-99%), 음성예측도는 43%(95% CI, 28-72%) 였다. 그러나급성동맥폐색이있었던 11 명 22 예의경우맥박산소포화도의민감도는 73%(95% CI, 37-93%), 특 이도는 100%(95% CI, 68-100%), 양성예측도는 100%(95% CI, 60-100%), 음성예측도는 79%(95% CI, 49-94%) 였다. 결론 : 휴대용디지털맥박산소포화도측정기를이용한무지의산소포화도측정은민감도가 ABI 와유사해선별검사로서의적합성은떨어지지만급성 으로발생한하지통증의경우외래나응급실에서척추성하지통증과의감별진단에도움이될수있다고사료된다. 색인단어 : 하지동맥질환, 산소포화도, 발목상완지수 약칭제목 : 휴대용산소포화도측정기 40