대한골절학회지제 21 권, 제 3 호, 2008 년 7 월 Journal of the Korean Fractrure Society Vol. 21, No. 3, July, 2008 고관절부골절환자에서수술후섬망을일으키는위험인자 김기환ㆍ고덕환ㆍ신주용ㆍ최진영ㆍ김응식ㆍ김동헌 건국대학교의과대학충주병원정형외과학교실 목적 : 고령의고관절부환자에서수술후섬망을일으키는원인이되는인자들을파악하여상관관계를알아보고자하였다. 대상및방법 : 2001년 3월부터 2005년 3월까지본원정형외과에서고관절부골절에대한수술적치료를시행한 65세이상의환자 135명중수술후섬망을보인 14명과 (10.4%) 수술후섬망을보이지않은 121 명의 (89.6%) 대조군간에섬망을일으키는원인으로알려진인자에대해비교조사하였다. 결과 : 수술후섬망군과비섬망군간의카이자승검사상 75 세이상의고령, 이전섬망의과거력, 인지기능장애가있는경우, 입원이나수상전보행능력이낮을수록, ADL 의존도가높을수록, 내과적동반질환이많을수록, 치매가있는경우, 수술후저산소증, 수술후전해질불균형이있는경우, 수술후헤모글로빈, 헤마토크릿수치가낮을수록, 수술후알부민수치가낮을수록섬망이잘나타났다 (p<0.05). 성별, 골절분류, 수술방법, 마취방법, 입원후수술까지의기간은수술후섬망군과비섬망군간의큰차이를보이지않았다. 결론 : 고령의고관절부골절환자에서수술후섬망을일으키는원인은다양하면서다인자적인성향이있었다. 따라서섬망의원인이되는여러인자에대한철저한이해와상관관계를파악하고대비하는것이수술후섬망의발생예방및고관절부수술후예후에좋은영향을줄것으로생각한다. 색인단어 : 수술후섬망, 고관절부골절, 위험인자 Risk Factors of Postoperative Delirium in Elderly Patients with Hip Fractures Ki-Hwan Kim, M.D., Duk-Hwan Kho, M.D., Ju-Yong Shin, M.D., Jin-Yong Choi, M.D., Eung-Sik Kim, M.D., Dong-Heon Kim, M.D. Department of Orthopedic Surgery, Konkuk University Chungju Hospital, College of Medicine, Konkuk University, Chungju, Korea Purpose: To find out the relationship between various risk factors and post-operative delirium in elderly patients with hip fractures. Materials and Methods: Out of 135 patients older than 65 years old who underwent the surgery for hip fracture in our department, between the periods of March 2003 to March 2005, 14 patients (10.4%) developed post-operative delirium and 121 patients (89.6%) did not. We studied risk factors of post-operative delirium in two groups. Results: In chi-square test between delirium group and non-delirium group, the patients were more likely to develop post-operative delirium if they had previous episodes of delirium, abnormal cognitive function, low walking ability before admission, high dependency on ADL (Activities of Daily Living), other medical accompanying diseases, history of dementia, post-operative hypoxia, post-operative electrolyte imbalance, low post-operative hemoglobin and hematocrit, low post-operative albumin and were older than 75 years old (p<0.05). Sex, type of fracture, anesthesia and the time between admission and operation did not show much difference between the two groups. Conclusion: The risk factors of postoperative delirium in elderly patients with hip fracture have a tendency to be multifactorial. Therefore, we conclude that being prepared by thorough understanding of the risk factors and their relationships will help prevent post-operative delirium and result in good postoperative prognosis. Key Words: Post-operative delirium, Hip fracture, Risk factors 통신저자 : 김동헌충북충주시교현 2 동 620-5 건국대학교충주병원정형외과 Tel:043-840-8250 ㆍ Fax:043-844-7300 E-mail:patella13@naver.com Address reprint requests to:dong-heon Kim, M.D. Department of Orthopedic Surgery, Konkuk University Chungju Hospital, College of Medicine, Konkuk University, 620-5, Gyohyeon 2-dong, Chungju 380-704, Korea Tel:82-43-840-8250 ㆍ Fax:82-43-844-7300 E-mail:patella13@naver.com 189
190 김기환, 고덕환, 신주용, 최진영, 김응식, 김동헌 서 론 Table 1. Classification of walk ability 섬망은다양한질병상태에서나타나는증후군이며정신상태의급성또는아급성변화로서고령의환자에서수술후발생하는주된합병증중의하나다. 고령의환자에서수술후발생한섬망은치료를어렵게만들뿐만아니라재원기간의연장및비용의증가라는결과를가져오게된다 2,3,20). 사망률또한높아병원내사망환자의 18% 를차지하고이중첫세달의사망률이 47% 에이른다는보고도있다 8,10,12,13,18). 심한섬망과호전되지않는섬망인경우사망률은더욱높아진다. 현재서양에서, 수술후섬망의유병률에대해보고된바에의하면일반수술후 7 14% 22,33), 고관절수술후 26 61% 2,9 11,20,23), 인공관절치환술후 13 41% 22,31,34) 에서섬망을보였다고한다. 그러나국내에는이에대한연구가미비한실정이다. 또한재원기간의연장과종종지속적일수있다는사실에서섬망의원인이되는여러인자에대한이해와상관관계를알아예방함으로써섬망으로인한환자의예후에좋은영향을줄것으로기대된다. 이에저자들은고령의고관절부골절환자에서수술후섬망의유병률및원인이되는인자들을파악하여상관관계를알아보고자하였다. 대상및방법 2001 년 3 월부터 2005 년 3 월까지본원정형외과에서고관절부골절에대한수술적치료를시행한 65 세이상의노인환자 135 명을대상으로하였다. 성비는남자 39 명, 여자 96 명이었고평균나이는 71.2 세 ( 범위 65 89 세 ) 였다. 수상원인은실족 110 예 (81.5%), 낙상이 11 예 (8.1%), 교통사고 14 예 (10.4%) 였다. 골절의분류로대퇴경부골절이 92 예였고, 대퇴전자간부골절이 43 예였으며, 수술방법으로는양극성반치환술이 114 예, 압박고나사고정술이 12 예, 다발성유관나사못고정술이 9 예였다. 65 세이하의환자, 수술후임의퇴원한경우, 사망한경우, 기록이부실한경우는제외하였다. 수술후섬망에대한평가는 Diagnostic and Statistical Manual IV (DSM IV) 진단기준을바탕으로한 Confusion Assessment Method (CAM) 를이용하여평가하였다. 입원당시정신상태에대한평가는본원신경과에서 Mini-mental status examination Korea (MMSE-K) 수치를이용하여평가하였고, 23 점이하를인지기능장애로하였다. 생활능력에대한평가는 Activities of Daily Living (ADL) 으로목욕하기, 옷입기, 용변보기, 거동하기, 대소변 Grade Walk ability 1 Ability to walk outdoors alone with or without an assistive device 2 Ability to walk outdoors with a helper 3 Ability to walk indoors alone with our without an assistive device 4 Ability to walk indoors with a helper 5 Unable to ambulate but able to sit on chair 6 Bedridden 가리기, 식사하기등의 6 가지항목의의존도여부를각항목의합으로측정하였다. 고령으로인한내과적동반질환은기왕력에대한문진및수술전기초적검사에의하여조사되었으며고혈압, 심근허혈을포함한심혈관계질환, 당뇨병, 호흡기계질환, 신장질환, 뇌혈관질환등이있었으며, 106 예 (78.6%) 에서 2 개이하의동반질환을가지고있었다. 입원전이나수상전보행능력의평가는 6 단계로분류하였다 (Table 1). 혈액검사는수술후 1 일째의결과로하였고, 수술후저산소증의유무는수술후 1 일째동맥혈가스분석상산소포화도가 90% 미만을경험한것으로정의하였다. 통계학적분석은 SPSS version 12.00 으로분석하였고, 독립변수와 ( 연령, 성별, 골절의분류, 수술방법, 내과적동반질환, 인지기능장애, 이전섬망의과거력, 치매의유무, 마취방법, 수상전보행능력, ADL (Activities of Daily Living), 마취방법, 입원후수술까지의기간, 수술후헤모글로빈, 헤마토크릿농도, 수술후알부민수치, 수술후저산소증 ) 섬망과의관계는 Chi-square test 와 t-test 로통계적처리후통계학적유의성은 p<0.05 수준에서검증하였다. 결 65 세이상의고관절부골절환자 135 명중수술후섬망을보인환자는 14 명 (10.4%) 이었다. 이중남자환자는 5 명 ( 전체남자환자의 12.8%), 여자환자는 9 명 ( 전체여자환자의 9.4%) 이었다. 평균연령은 77.8 세 ( 범위 69 87 세 ) 였으며, 75 세이상이 10 명으로전체섬망환자의 71.4% 를차지하였다. 발병시기는 9 명이술후 2 일째, 5 명이술후 3 5 일째였다. 75 세이상의나이, 내과적동반질환이많을수록, 섬망의과거력이있었던경우, 입원전이나수상전보행능력이낮을수록, 치매가있는경우, 인지기능장애가있는경우, ADL 의존도가높은경우에수술후섬망의발생이유 과
고관절부골절환자에서수술후섬망을일으키는위험인자 191 Table 2. Comparision of various factors between the postoperative delirium and the control group Table 3. Comparision of post-operative laboratory data between the post-operative delirium and the control group Factors Delirium group Control group p value Delirium group (mean±sd) Control group (mean±sd) p value Number of patients 14 (10.4%) 121 Gender Male 5 34 Female 9 87 Age (years) 75 10 58 <0.05 Fracture type Neck 10 82 Intertrochanter 4 39 Number of cormobidities <0.05 0, 1 or 2 4 102 3 or more 10 19 Past history of delirium <0.05 Present 9 9 Not present 5 112 Anesthesia General 7 66 Spinal 7 55 Dementia <0.05 Present 6 7 Not present 8 114 Admission-surgery interval Under 5 days 9 93 Over 6 days 5 28 Operation methods Bipolar hemiarthroplasty 12 102 Compression hip screw 1 11 Multiple cannulated screw 1 8 Abnormal cognitive function 9 58 <0.05 Walking ability at admission <0.05 Grade 1 2 5 99 Grade 3 6 9 22 ADL (mean±sd) 4.48±2.49 1.91±1.54 <0.05 의하게높았다 (p<0.05). 성별, 골절분류, 수술방법, 마취방법, 입원후수술까지의기간은통계학적으로의미가없었다 (Table 2). 수술후섬망군과비섬망군간의혈액검사와수술후섬망과의유의성을보면 Table 3 과같다. 수술후헤모글로빈, 헤마토크릿이낮을수록, 알부민수치가낮을수록, 전해질불균형이있는경우, 저산소증이있는경우에수술후섬망과의유의성이있는것으로나타났다 (p<0.05). 고 섬망은다양한질병상태에서나타나는증후군이며, 인지기능장애의전반적인손상, 의식수준의저하, 주의력의이상, 정신운동성활동의증가나감소, 수면 - 각성주기의장애 찰 Hemoglobin (g/dl) 9.8±0.7 11.2±1.7 <0.05 Hematocrit (%) 28.4±2.8 33.5±5.1 <0.05 Sodium (meq/l) 128±3.5 136±3.0 <0.05 Potassium (meq/l) 3.6±0.4 4.1±0.6 <0.05 Albumin (g/dl) 2.8±0.4 3.1±1.2 <0.05 Total protein (g/dl) 6.1±0.4 6.5±0.7 Post-operative hypoxia 10 (71.4%) 53 (43.8%) <0.05 를특징으로하는급성발병의일과성기질증후군으로고령의환자에서수술후발생되는주된합병증중하나다. 특히정형외과에서수술후섬망은재원기간의연장과비용의증가뿐만아니라보행능력및기능회복에심각한저하를초래하여술후합병증과 1년내사망률을높이는것으로보고되고있다 29). 정형외과환자에서수술후섬망의유병률에대해보고된바에의하면, 고관절치환술후 9.5 61.3%, 고관절과슬관절치환술후 26% 에서섬망을보인다고한다 2,4,11,24,26). 65세이상의고관절부골절환자를대상으로한본연구에서는수술후섬망의유병률이 10.4% (14예) 로서양에비해낮은편이었으며, 이는조사대상환자의연령, 진단기준및진단방법의차이, 일시적으로발생하였다가회복되기를반복하는섬망의특징, 모집단의특성에따라달라질수있기때문이라고생각한다. Kagansky 등 16), Schuurmans 등 32) 외에여러보고에따르면수술후섬망의위험인자를분류하였는데종합해본결과크게선행인자 (predisposing factors) 와유발인자 (precipitating factors) 로분류할수있었다 6,7,15,19). 선행인자로는나이, 입원전이나수상전보행능력, ADL 의존도, 인지기능장애, 치매, 내과적동반질환등이있고, 유발인자로는마취방법, 입원후수술까지의기간, 수술후비정상혈액검사수치, 수술후저산소증등이있었다. 또한 Edlund 등 7) 에의하면고관절부골절환자에서수술이전에통증과침상고정등으로인한스트레스로섬망이발생할수있다고하였고본원에서도수술이전섬망이 2예에서발생하였으며술전섬망을일으키는인자들에대한추후연구가필요할것으로생각한다. 연령과의관계에서본연구에서는수술후섬망환자 14 명중 10명이 (71.4%) 75세이상으로통계학적으로유의한상관관계를보였으며, 성별과의차이를볼때 Edelstein 등 6) 은남자에서수술후섬망의발생이높다고보고하였으나, 본연구에서는통계학적으로의의있는상관관계를발견할
192 김기환, 고덕환, 신주용, 최진영, 김응식, 김동헌 수없었다. 입원전이나수상전보행능력, ADL (Activities of Daily Living) 과의관계에서는많은저자들이수술후섬망의발생을증가시키는고위험군으로보고있으며 17,21,27), 본연구에서도통계학적으로유의하였다. 치매, 인지기능장애와수술후섬망과의관계에서여러연구에서수술후섬망의발생과높은상관관계가있음을보고하고있으며 8,10,14), Rockwood 등 30) 도치매와섬망의뇌손상병태생리가유사한과정을보이고치매환자는섬망에대해낮은역치를가지고있다고하였다. 본연구에서도유의한상관관계를보였다. 내과적동반질환에있어서 Schuurmans 등 32) 은내과적동반질환이많을수록수술후섬망의발생률이높다고하였으나, Kawaguchi 등 17) 은기존질환과섬망발생과는무관하다고하였다. 본연구에서는수술후섬망군에서 3 개이상의내과적동반질환을가지고있는환자가 71.4% 를차지하고있어수술후섬망과의유의한상관관계를보였다. 마취방법과수술후섬망의관계에있어서는아직까지많은논란이있는데여러보고에의하면마취방법과섬망의발생률과는관련이없다고보고하고있다 9,25). Bedford 1) 는전신마취가뇌의저산소증을야기하여수술후섬망을일으킨다고주장하였고 Gustafson 등 10) 은척추마취가저혈압의위험성이더커수술후섬망을일으킨다고주장하였다. 본연구에서는마취방법에있어서수술후섬망군과비섬망군간에통계학적으로유의한차이를보이지않았다. Kagansky 등 16) 은입원후수술까지의기간과수술후섬망과의관계는관련이없다고보고하였으며, 본연구에서도통계학적으로의의있는상관관계를발견할수없었다. 수술후낮은헤모글로빈, 헤마토크릿수치와수술후섬망과의관계에서 Marcantonio 등 22) 은수술후헤마토크릿이 <30% 이하일때섬망의발생위험이증가한다고보고하였고, Kawaguchi 등 17) 은수술후낮은헤모글로빈, 헤마토크릿수치는뇌의산소공급을감소시켜섬망을야기한다고주장하였으며, 이러한환자에게수술후조기에수혈을해주는것이섬망의예방에유용하다고하였다. 본연구에서도수술후낮은헤모글로빈, 헤마토크릿수치와섬망의유병률과의관계에서통계학적으로의의있는상관관계를보였다. 전해질불균형, 낮은알부민수치도섬망의발생과유의한상관관계를나타냈다. 수술후저산소증과섬망과의관계에서 Clayer 와 Bruckner 5) 는대퇴경부골절환자나고관절전치환술을시행받은환자에서충분한산소공급이섬망의발생을감소시킨다고주장하였으며이러한환자들에서모니터를이용한지속적인 말초산소포화도 (peripheral oxygen saturation) 감시가필요하다고하였다. 본연구에서도섬망군에서수술후저산소증을보인환자가 71.4% 를차지하고있어유의한상관관계를볼수있었다. 수술후섬망환자들은정신적흥분및지남력장애로수술후치료가어렵기때문에주의가필요하다. 따라서수술후섬망환자의치료에서가장중요한점은조기에정확한진단을내리고원인을제거하는것이다. Potter 28) 는일반적인보존치료로수분균형, 영양, 안정과휴식등이있으며이는예방과도밀접한관련이있다고하였으며가족모두에게환자에대한설명과지지확신이필요하다고하였다. 가족들의방문이나적절한자극을제공하는조용하고잘정돈된병실이환자에게도움이되며밤에는낮은조도의불빛이종종유용하다. 시계나달력, 가족사진그리고개인용품들을이용하여환자에게자주지남력을일깨워주는것이유용하고감각장애를보이는환자에게는안경과보청기등이적절하게도움이된다. 또한수술후조기보행및조기능동운동을시행하며 Foley 도뇨관과같은억제제를조기에제거하는것이섬망의예방에중요하다. O'keeffe 와 Ni Chonchubhair 26) 는섬망의치료시진정제사용은오히려섬망상태를지연시킬수있다고하였으며본원에서는특별한증상 ( 공격성, 초조, 환각 ) 이있을시에만소량의진정제를사용하였다. 수술후섬망은일반적으로변동하는경과를밟는것이특징적이며또한몇주안에자연회복되는특성을가지고있다. 본원에서는신경정신과와의협진을통해조기진단및치료로 12 예에서발생 2 주안에완전히회복하였으나 2 예에서는지속적인섬망상태를보였다. 결 고령의고관절부골절환자에서수술후섬망을일으키는원인은다양하면서다인자적인성향이있었다. 따라서섬망의원인이되는여러인자에대한철저한이해와상관관계를파악하고대비하는것이수술후섬망의발생예방및고관절부수술후예후에도좋은영향을줄것으로생각한다. 론 참고문헌 1) Bedford PD: Adverse cerebral effects of anesthesia on old people. Lancet, 269: 259-263, 1955. 2) Berggren D, Gustafson Y, Eriksson B, et al: Postoperative confusion after anesthesia in elderly patients with femoral neck fractures. Anesth Analg, 66: 497-504, 1987.
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