내과적흉강경검사의진단적유용성과안전성 1 건양대학교의과대학내과학교실, 2 흉부외과학교실, 3 마취과학교실양정경 1, 이정호 1, 권미혜 1, 정지현 1, 이고은 1, 조현민 2, 김영진 2, 정성미 3, 최유진 1, 손지웅 1, 나문준 1 Diagnostic Accuracy and Safety of Medical Thoracoscopy Jung Kyung Yang, M.D. 1, Jung-Ho Lee, M.D. 1, Mi-Hye Kwon, M.D. 1, Ji Hyun Jeong, M.D. 1, Go Eun Lee, M.D. 1, Hyun Min Cho, M.D. 2, Young Jin Kim, M.D. 2, Sung Mee Jung, M.D. 3, Eu Gene Choi, M.D. 1, Ji Woong Son, M.D. 1, Moon Jun Na, M.D. 1 1 Department of Internal Medicine, 2 Thoracic & Cardiovascular Surgery, 3 Anesthesiology, College of Medicine, Konyang University, Daejeon, Korea Background: The causes of the pleural effusion are remained unclear in a the substantial number of patients with exudative effusions determined by an examination of the fluid obtained via thoracentesis. Among the various tools for diagnosing exudative pleural effusions, thoracoscopy has a high diagnostic yield for cancer and tuberculosis. Medical thoracoscopy can also be carried out under local anesthesia with mild sedation. The aim of this study was to determine diagnostic accuracy and safety of medical thoracoscopy. Methods: Twenty-five patients with exudative pleural effusions of an unknown cause underwent medical thoracoscopy between October 2005 and September 2006 in Konyang University Hospital. The clinical data such as age, gender, preoperative pulmonary function, amounts of pleural effusion on lateral decubitus radiography were collected. The vital signs were recorded, and arterial blood gas analyses were performed five times during medical thoracoscopy in order to evaluate the cardiopulmonary status and acid-base changes. Results: The mean age of the patients was 56.8 years (range 22-79). The mean depth of the effusion on lateral decubitus radiography (LDR) was 27.49 mm. The medical thoracoscopic pleural biopsy was diagnostic in 24 patients (96.0%), with a diagnosis of tuberculosis pleurisy in 9 patients (36%), malignant effusions in 8 patients (32%), and parapneumonic effusions in 7 patients (28%). Medical thoracoscopy failed to confirm the cause of the pleural effusion in one patient, who was diagnosed with tuberculosis by a pericardial biopsy. There were no significant changes in blood pressure, heart rate, acid-base and no major complications in all cases during medical thoracoscopy (p>0.05). Conclusions: Medical thoracoscopy is a safe method for patients with unknown pleural effusions with a relatively high diagnostic accuracy. (Tuberc Respir Dis 2007; 63: 261-267) Key Words: Accuracy, Biopsy, Diagnosis, Medical thoracoscopy, Pleural effusion, Safety. 서 측와위초음파나흉부방사선사진상의미있는흉수가확인되지만심부전등과같이흉수의명확한원인을알수없는경우진단적흉강천자를하여흉수검사를하게된다 1. 그러나병력청취와이학적검사그리고흉강을천자하여얻은흉수로시행한미생물학적, 세포학적검사와생화학적검사에도불구하고정 론 Address for correspondence: Moon Jun Na, M.D. Department of Internal Medicine, College of Medicine, Konyang University Hospital, 685 Gasunwon-dong, Seo-gu, Daejeon, 302-718, Korea Phone: 82-42-600-8968 E-mail: mjna@ns.kyuh.co.kr Received: Jun. 14. 2007 Accepted: Sep. 4. 2007 확한진단에이르지못하는경우에는맹검적흉막생검을시도해왔다 2. 특히악성이나결핵성흉수는흉막생검을통한조직학적진단이필요하다 3. 맹검적흉막생검시우리나라에서흔한결핵성흉수의진단율은 60-80% 로알려져있지만 4-7, 악성흉수환자에서는진단율이 50% 에불과하고특히악성중피종의진단율은 20% 로매우낮은편이다. 또한맹검적흉막생검은시술에따른통증, 기흉, 미주신경반사반응, 혈흉및혈종등의합병증이발생할수있다. 이에비해흉강경은직접병변을보면서조직검사를시행하기때문에맹검적흉막생검에비해진단율이높고비교적안전한시술이다. 최근에는전신마취가필요하지않은내과적흉강경의진단율이전신마취하에시행하는외과적흉강경과큰차이가없다고보고되고있다 8-12. 그러나흉강경시행시시야를확 261
JK Yang et al: Diagnostic accuracy and safety of medical thoracoscopy 보하기위해흉강내에이산화탄소를주입하였을때심박동수와동맥압을현저히감소시키거나 13, 흉강경시술자체와환자의과도한긴장에의하여빈맥이나부정맥이발생할수있음이보고된바가있다 14,15. 본연구는흉수의원인을진단하기위해기존의외과적흉강경보다덜침습적이며국소마취와진정제투여만으로도시술이가능한내과적흉강경의진단정확도를확인하고나아가활력징후와동맥혈가스분석을통하여시술의안전성을알아보고자전향적으로연구하였다. 대상및방법 2005년 10월부터 2006년 9월까지건양대학교병원에입원한삼출성흉수가있는환자중가래검사, 흉강천자를통한미생물배양검사, 세포진검사등으로흉수의원인을진단할수없었던 25명의환자를대상으로하였다. 모든환자들에게연구의목적과방법을설명하고사전동의서를받은후외과적흉강경에사용하는 10 mm보다작은 5 mm 경직성흉강경으로국소마취와진정제만을사용하여내과적흉강경검사를 시행하였다 (Figure 1, 2). 흉부측와위사진에서흉수의두께 (depth of effusion on lateral decubitus radiography, LDR) 가 10 mm 미만인경우, 예상여명이 1 개월미만인경우, 1시간정도의측와위를유지할수없는경우, 출혈의경향이있는경우는연구대상에서제외하였다. 시술전문진과이학적검사를통하여악성종양등의환자의병력을확인하였고, 흉부방사선사진, 흉부컴퓨터단층촬영을통하여흉수의유무와양을확인하였다. 수술실에서시술전 2% 리도카인 (lidocaine) 으로최대 10 ml를사용하여피부부터벽쪽흉막까지국소마취를시행하였고진정효과를위해미다졸람 (midazolam) 2-3 mg을정주하였으며시술중환자에게 5 ml/min의산소를마스크를통해공급하였다. 환자는흉수가있는쪽이위로오도록측와위자세를취한후흉강경과조직겸자삽입을위해투관침 (trocar, WOLF Company, Knittlingen, Germany) 으로 5 mm 통로를만들고, 5 mm 흉강경 (5 mm telescope, WOLF Company, Knittlingen, Germany) 으로흉강내병변을육안으로관찰한후, 5 mm 흉강경조직생검겸자 (thoracoscopic grasping forcep, Tyco-AutoSuture; Tyco Healthcare, Gosport, UK) 를이용하여조직생검을시행하였다 (Figure 1, 2). 조 Figure 1. The instruments of 5 mm minithoracoscopy. Top. 5 mm trocar (WOLF Company, Knittlingen, Germany). 1.8 mm aspiration needile (WOLF Company, Knittlingen, Germany). 5 mm telescope (WOLF Company, Knittlingen, Germany). Endohook electrocautery (WOLF Company, Knittlingen, Germany) Bottom. 5 mm thoracoscopic grasping forcep. (Tyco- AutoSuture Tyco Healthcare, Gosport, UK) Figure 2. The comparisons of 5 mm & 10 mm trocar and telescope. Top. 5 mm trocar (WOLF Company, Knittlingen, Germany ). 10 mm trocar (WOLF Company, Knittlingen, Germany). 5 mm telescope (WOLFCompany, Knittlingen, Germany) Bottom. 10 mm telescope (WOLF Company, Knittlingen, Germany) 262
Tuberculosis and Respiratory Diseases Vol. 63. No.3, Sep. 2007 직생검은결절, 섬유성화농성변화등의이상소견이보이는흉막부위에서시행하여동결절편조직학적소견을확인하였고흉강경으로이상소견이발견되지않을경우에는무작위적으로조직생검을시행하였으며, 동결절편의조직학적소견이악성종양으로확인될경우에는수술실에서탈크 (Talc) 를사용하여흉막유착술을시행하였다. 시술이종료되면흉관을유치하였고흉수의원인은최종생검조직검사결과를통하여확진하도록하였다. 시술전후의환자통증정도를확인하여통증을호소할경우페치딘 (pethidine) 을정주하였다. 시술의안전성파악을위하여심전도감시와함께시술전, 시술을위해측와위로의자세변화후, 흉강경삽입후, 조직생검시및회복기등총 5차례에걸쳐활력징후와동맥혈가스분석을시행하였다. 활력징후, 동맥혈산소분압, 이산화탄소분압및평균동맥압의차이를성별, 연령, 흉수의양과, 폐기능정도에따라비교하였다. 수치는평균 ± 표준편차로표시하였고통계프로그램인 SPSS (version 12.0) 를이용하여반복분산분석으로통계처리하였으며, p값이 0.05 이하인경우통계적으로의미있는것으로판단하였다. 결 환자는총 25명으로남자가 15명, 여자가 10명이었으며연령은 22세부터 79세로평균연령은 56세이었다 (Table 1). 평균 1초간노력성호기량 (FEV1) 은 1.61 Table 1. Characteristics of 25 patients with medical thoracoscopy Variable Value Age (years) 56.8 ± 15.0 (22-79) Male:Female (n) 15:10 FEV 1 (L) FEV 1 (%) of predicted value 1.61 ± 0.61 (1.13-3.30) 61.8 ± 17.7 Left:Right (n) 13:12 LDR (mm) 27.4 ±19.6 (12-73) Op time (min) 23.2 ± 8.2 (10-40) Chest tube indwelling (day) 8.5 ± 4.0 (3-18) Initial mean arterial BP (mmhg) 100.6 ± 15.1 (82-136) Values are mean ± SD. LDR: depth of pleural effusion on lateral decubitus radiography 과 L로정상예측치의 61.8±17.7% 이었고, 좌측흉수 13 예, 우측흉수 12예였으며, LDR은평균 27.4 mm이었고평균시술시간은 23.2 분이었고평균흉관유치기간은 8.5일이었고시술전평균동맥압은 100.6 mmhg이었다 (Table 1). 조직생검을통해 24명 (96%) 의환자에서진단이되었다. 흉수의원인은결핵성흉수 9예 (36%), 부폐렴성흉수 7예 (28%), 악성흉수 8예 (32%) 가확인되었으며, 내과적흉강경을통한흉막조직검사로진단되지않은 1예 (4%) 는추후심장막조직생검을통해결핵성흉수및결핵성심장막삼출물로진단하였다 (Table 2). 흉수진단을위한기존의검사방법중흉수 adenosine deaminase(ada) 의경우기준을 50 IU/L 로하였을때결핵성병변에대한민감도 100%, 특이도 83.3% 를보였고흉수 carcinoembryonic antigen (CEA) 수치는기준을 5.0 ng/ ml로하였을경우악성병변에대한민감도 71.4%, 특이도 100% 로나타났다. 시술중 5명이통증을호소하여진통제투여로통증을조절하였으며, 폐렴, 혈흉, 피하기종, 객혈이나발열을보이거나시술과관련되어사망한환자는없었다. 5차례의활력징후측정과동맥혈가스분석을시행한결과시술중동성빈맥이외의부정맥은관찰되지않았다. 수축기혈압이 100 mmhg이하로떨어지거나산소분압이 70 mmhg 이하로감소된경우는없었으며, 동맥혈이산화탄소분압이 35 mmhg 이하로감소된경우는 6명이있었으나임상적의미는없었다. 시간의흐름에따라동맥혈내산소분압은 153.4 mmhg, Table 2. Final diagnosis of patients with medical thoracoscopy Diagnosis Number (%) Benign 16 (64) Parapneumonic effusion 7 (28) Tuberculosis 9 (36) Malignant 8 (32) Primary lung cancer 6 (24) Metastatic Cholangiocarcinoma Esophageal cancer Nondiagnostic 2 (8) 1 (4) 1(4) 1(4) Total 25 263
JK Yang et al: Diagnostic accuracy and safety of medical thoracoscopy Figure 3. Changes of PaO 2, PaCO 2 and MAP in patients aged below or above 65 years old through the process of medical thoracoscopy. PaO 2: arterial oxygen tension; PaCO 2: arterial carbon dioxide tension; MAP: mean arterial pressure. Figure 5. Changes of PaO 2, PaCO 2 and MAP in patients with LDR below or above 27.4 mm through the process of medical thoracoscopy. PaO 2: arterial oxygen tension PaCO 2: arterial carbon dioxide tension MAP: mean arterial pressure LDR: depth of pleural effusion on lateral decubitus radiography. Figure 4. Changes of PaO 2, PaCO 2 and MAP by sex differences through the process of medical thoracoscopy. PaO 2: arterial oxygen tension PaCO 2: arterial carbon dioxide tension MAP: mean arterial pressure. 158.8 mmhg, 164.5 mmhg, 149.1 mmhg, 144.4 mm Hg로시술이끝날무렵시술전보다떨어지는추세를보이나, 통계적유의성은없었고 (p=0.262), 동맥혈내이산화탄소분압은 34.3 mmhg, 36.5 mmhg, 37.6 mmhg, 38.2 mmhg, 34.5 mmhg로시술중상승하고회복기에시술전과비슷한수치로떨어지는경향을보이나유의한차이는없었다 (p=0.364). 평균동맥압은 100.6 mmhg, 100.3 mmhg, 99.52 mmhg, 102.3 mmhg, 102.4 mmhg으로흉막천자시일시적으로하강하였으나이변화들은통계적으로의미는없었고 Figure 6. Changes of PaO 2, PaCO 2 and MAP in patient with FEV 1% below or above 50 through the process of medical thoracoscopy. PaO 2 : arterial oxygen tension PaCO 2 : arterial carbon dioxide tension MAP: mean arterial pressure. (p=0.447), 또한심박동수 (p=0.244), 산도 (ph)(p=0.664), 탄산수소이온 (HCO3-) (p=0.773) 도유의한변화는없었다. 동맥혈산소분압의변화는 65세이상과미만 (p=0.175)(figure 3), 남자와여자 (p=0.477)(figure 4), LDR 27.4 mm 이상과미만 (p=0.786)(figure 5), 시술전 FEV1 50% 이상과미만 (p=0.570)(figure 6) 으로나눈각그룹간에서통계적유의한차이는보이지는않았으며, 그밖의동맥혈가스분석결과와활력징후도각그룹간의유의한차이는없었다. 264
Tuberculosis and Respiratory Diseases Vol. 63. No.3, Sep. 2007 고찰본연구에서 25명의삼출성흉수환자에서내과적흉강경을시행하여 96% 의높은진단율을확인하였고, 혈역학적불안정이나저산소증은없었다. 또한연령, 성별, 흉수의양, 시술전폐기능에따른통계적유의한차이는없었으며미주신경반사반응, 혈흉, 혈종, 피하기종등의합병증도없었다. 흉강경은 1913년스톡홀름의 Jacobaeus에의해 2 예의삼출성흉수의정확한진단을위해최초로도입되었다 16. 그후 1960년대초유럽에서주로내과의사들에의하여흉강경이시행되었고, 1990년대초반내시경기술의발전으로흉강경은흉부외과의사들에의해재조명되었으며, 전신마취와함께선택적인기도삽관과최소한 3개이상의통로가필요하여이를다시 video-assisted thoracic surgery(vats) 라부르게되었다 17-19. 이러한흉강경시술의발전을토대로미국에서내과적흉강경을도입하여사용하게되었으며 1994년조사에의하면미국내호흡기내과의사의 5% 가량이임상에적용하기시작하였다고한다 20. 내과적흉강경은전신마취하에시행하는외과적흉강경에비해국소마취만을필요로하며수술중환자의의식상태를명료하게유지할수있으며세개의큰통로가필요한외과적흉강경에비해두개이하의작은통로로시술이가능하기때문에덜침습적이며술후회복이빠른장점이있다 9. 흉강경은직접병변을보면서조직검사를시행하기때문에맹검적흉막생검에비해진단율이높은것으로알려져있다 10. 여러연구에서국소마취하에비교적간단하게시행할수있는내과적흉강경의진단율은외과적흉강경과큰차이가없다고보고하고있다 8-12. 본연구에서흉수검사를통하여진단되지않은 25명의환자중 24명이내과적흉강경검사를통해진단되어 96% 의진단율을나타내었는데, 이는최근우리나라의한연구에서 9 보고한 93.3% 의진단율과비슷하게매우높은수준의진단율이었다. 또한조직학적진단결과외국의연구들과비교하였을때결핵성흉수가현저히많이확인되었고전체환자들중부폐렴성흉수가차지하는비중이커서항생제사용을통 한폐렴치료로인해흉관유치기간이다소길었다. 맹검적흉막생검을통하여악성흉수로진단된경우에는흉관유치와탈크주입등의추가적인시술을필요로하지만, 내과적흉강경을시행할경우는한번의시술로진단과악성흉수에대한치료를시행할수있는장점이있다. 흉강경과관련된합병증과시술중의호흡기계, 심혈관계변화에대한연구는여러논문에서발표되었고 14,21, 실제시술과관련되거나환자의긴장에의하여빈맥과부정맥이발생한다는연구가있었다 15. Page 등 15 은전신마취하에시행한외과적흉강경에서 9.1% 의호흡기계합병증발생률을보고하였고, Boutin 등 23 은 102명을대상으로국소마취하에흉강경을시행한결과혈역학적불안정이나가스누출로인해 1.9% 에서개흉술로전환하였고, 5% 에서합병증이발생하였다고보고하였다. 그러나내과적흉강경과관련된합병증이나호흡기계, 심혈관계변화등의안전성에대한연구는미미한실정이다. 본연구에서내과적흉강경을시행하면서시술의합병증으로혈흉이나, 혈종, 피하기종등이발생한경우는없었고 5예에서시술도중통증을호소하여추가적인진통제를투여한후더이상의통증호소는없었다. 내과적흉강경을시행하는동안흉강경의시야를좋게하기위하여가능한한폐를허탈시키게되므로시술중감소된폐기능에의해갑작스런환기와관류의불균형이발생할수있을것으로예상할수있다 21. 이에대하여 Olenburg와 Newhouse 등 14 이초기정상동맥혈가스소견을보인 12명환자들에서흉강경검사시임상적으로큰의미가없는산소포화도와심박동리듬의변화에대해보고한바있고, Faurschou 등 21 은 8명의흉수환자를대상으로흉강경시술중동맥혈가스분석과활력징후를측정하였으나시술중환기와관류의갑작스러운변화는보이지않았다고보고하였다. 이에반해 Toshiya 등의연구에서는 VATS 시폐허탈을유도하기위해흉강내로이산화탄소를주입할때심박동수와동맥압이현저히감소되는위험성이있다고보고하였다 13. 본연구에서는 6예에서시술중호흡수의증가에 265
JK Yang et al: Diagnostic accuracy and safety of medical thoracoscopy 따른동맥혈이산화탄소분압의감소소견이관찰되었고흉막천자와이산화탄소주입시평균동맥압의의의있는감소는없었으며동성빈맥이 2예에서발생한것외에치명적인부정맥은발생하지않았다. 환자들의연령에따른시술의혈역학적변화여부를확인하기위하여 65세를기준으로분류하여비교하였고, 성별, 평균 LDR 수치인 27.4 mm을기준으로한흉수의양, 1초간강제호기량 (FEV1) 의예측치 50% 를기준으로한시술전폐기능에따라환자를분류하여비교하였으나의미있는변화가없었다 (Figure 3-6). 또한활력징후와동맥혈산소분압, 동맥혈산도 (ph), 탄산수소이온 (HCO - 3 ) 등의유의한변화도관찰되지않았다. 본연구에서는시술중심박출량, 폐동맥압, 전신혈관저항지수, 폐혈관저항지수및폐내단락의양을측정하지못하였지만활력징후와동맥혈가스분석을통해혈역학적안정성을확인할수있었다. 또한폐기능이감소된환자, 65세이상의고령환자, LDR 27.4 mm 이상으로다량의흉수가있는환자에서도내과적흉강경을안전하게시행할수있음을확인하였다. 요약배경 : 삼출성흉수환자의적지않은빈도에서원인이불명확하다. 삼출성흉수를진단하기위한다양한방법중에서내과적흉강경은국소마취하에서시행할수있으며악성종양이나결핵에서진단율이높으며, 진정제와국소마취상태에서시행할수있다. 본연구의목적은내과적흉강경의진단적정확성과안전성에대해알아보고자하였다. 대상및방법 : 2005년 10월부터 2006년 9월까지 25 명의원인을알수없는삼출성흉수환자를대상으로내과적흉강경을시행하였다. 성별, 연령시술전폐기능, 흉부측와위사진에서흉수의두께 (LDR) 등의정보를얻었다. 내과적흉강경시행도중활력징후를기록하였고동맥혈가스분석을 5차례시행하여혈역학적상태와산-염기균형상태를파악할수있도록하였다. 결과 : 환자의평균연령은 56.8(22-79) 세였고, 흉 부측와위사진에서흉수의두께는 27.49 mm이었다. 내과적흉강경을이용한흉막조직생검으로 24명 (96%) 이진단되었으며, 결핵성흉막염이 9명 (36%), 악성흉수가 8명 (32%), 부폐렴성흉수가 7명 (28%) 이었다. 내과적흉강경으로흉수의원인을알아낼수없었던 1명 (4%) 은추후에심장막조직생검으로결핵으로진단되었다. 내과적흉강경중혈압, 심박동수, 산- 염기상태의변화는보이지않았다 (p>0.05). 결론 : 내과적흉강경은진단율이높으면서도안전한시술이다. 2006 결핵및호흡기학회추계학술대회구연발표함. 참고문헌 1. Light RW. Clinical practice. Pleural effusion. N Engl J Med 2002;346:1971-7. 2. Maskell NA, Butland RJ. BTS guidelines for the investigation of a unilateral pleural effusion in adults. Thorax 2003;58 suppl2:ii8-17. 3. Baumann MH. Closed needle biopsy of the pleura is a valuable diagnostic procedure. J Broncho 1998;5:327-31. 4. Salyer WR, Eggleston JC, Erozan YS. Efficacy of pleural needle biopsy and pleural fluid cytopathology in the diagnosis of malignant neoplasm involving the pleura. Chest 1975;67:536-9. 5. Kennedy L, Sahn SA. Noninvasive evaluation of the patient with a pleural effusion. Chest Surg Clin N Am 1994;4:451-65. 6. Valdes L, Alvarez D, San Jose E, Penela P, Valle JM, Garcia-Pazos JM, et al. Tuberculous pleurisy: a study of 254 patients. Arch Intern Med 1998;158:2017-21. 7. Prakash UB, Reiman HM. Comparison of needle biopsy with cytologic analysis for the evaluation of pleural effusion: analysis of 414 cases. Mayo Clin Proc 1985;60:158-64. 8. Harris RJ, Kavuru MS, Rice TW, Kirby TJ. The diagnostic and therapeutic utility of thoracoscopy: a review. Chest 1995;108:828-41. 9. Kim WJ, Lee HY, Lee SH, Cho SJ, Park WS, Kim JK, et al. Diagnostic accuracy of 2-mm minithoracoscopic pleural biopsy for pleural effusion. Tuberc Respir Dis 2004;57:138-42. 10. Malthaner RA, Inculet RI. Minithoracoscopy for pleural effusions. Can Respir J 1998;5:253-4. 11.Mathur PN, Astoul P, Boutin C. Medical thorac- 266
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