대한소화기내시경학회지 2008;36(Suppl. 1):15-20 고위험환자에서의내시경검사 연세대학교의과대학내과학교실 이상길 서 주지하는바와같이한국에서남녀를통틀어한국에서가장발생빈도가높은암은위암이고상부위장관내시경이위암을조기진단하는첨병역할을하고있다는점을부인하기는힘들다. 더불어내시경검사는비교적덜침습적이며안전하고진단및치료효과를동시에가지고있기에, 상부위장관내시경검사는간단한혈액검사처럼거리낌없이시행되고있다. 그러나모든의료술기에는환자에따라서우발증이나합병증발생의위험이증가할수있기때문에술기이전에충분한고려가필요하다. 1 기본적으로내시경을실시하는모든의사는내시경을하기전에내시경의적절한적응증에해당되는지, 내시경검사로인해환자가얻을수있는이점과발생할수있는위험에대해서숙고를해야한다. 특히내시경시술의합병증이높을것으로예상되는환자를미리예측하는것은적절한적응증을확보하는것만큼이나중요하다. 본글에서는내시경검사의합병증이발생할위험성이높은환자를알아보고각각에서내시경검사시에주의해야할점을기술하고자한다. 론 내시경검사의고위험군환자 일반적으로내시경검사는안전한검사이지만, 환자의상태나동반질환의유무에따라서합병증이생길가능성이증가할수있다. 그렇기때문에합병증을증가시킬수있는질환이나환자의상태에대해서정확히알고있는것이중요하다. 환자의상태중에서는패혈증이나, 심한탈수에의한쇼크, 고연령, 약물중독자, 임신이나고도비만이있는경우가고위험군에해당이된다 (Table 1). 심혈관질환중에는부정맥, 인공박동기삽입, 관상동맥질환, 심근경색, 울혈성심부전등이해당되고, 호흡기질환에서는만성폐쇄성폐질환, Table 1. High Risk Patients for Endoscopy Systemic conditions Sepsis Shock Dehydration ardiovascular conditions Arrhythmias ardiac pacemaker oronary artery disease History of myocardial ischemia ongestive heart failure Psychiatric conditions Uncooperative attitude Mental disorders Pulmonary dysfunction hronic obstructive airways disease Interstitial lung disease Neurological conditions Seizure disorders History of stroke Gastrointestinal/hepatic conditions Active gastrointestinal bleeding Liver dysfunction irrhosis Genitourinary conditions Renal dysfunction Urinary retention Social conditions Elderly or young age hronic use of prescribed sedatives Substance abuse History of drug allergy Pregnancy obesity History of radiation therapy 간질성폐질환등이해당된다. 소화기질환에서도급성위장관출혈과간부전에서합병증의위험도가증가할수있다. 내시경시술중의우발증및합병증은기존에가지고있던질환이악화되어발생할수도있지만, 건강한성인에있어서도내시경검사중에는주로심혈관호흡계이상의위험도가증가할수있다. 한보고에서는내시경중에나타날수있는합병증이나사망의 50% 이상이심혈관호흡계의이상변화에의한다고한다. 2 그러므로우선내시경시술에의한심혈관및호흡계의변화를알아보도록한다. 내시경시술에의한심혈관및호흡계의변화 심장의박동이나관상동맥으로의혈류는주로자율신경계에의해서조절이되고, 이중부교감신경계는박동을늦추게한다. 특히미주신경톤 (vagal tone) 은부정맥으로인한심근손상이나심장돌연사 (sudden cardiac 15
16 대한소화기내시경학회지 2008;36(Suppl. 1):15-20 death) 를방지하는데중요한역할을한다. 3 교감신경은역시심장박동을조절하여심근의흥분성 (excitability) 을증가시키는역할을한다. 내시경시술중에나타나는심장문제는주로이러한자율신경계의균형에부조화가생기면서일어나는것으로추정되는데, 부교감신경톤이감소하고, 교감신경톤이증가하여빈맥, 심근허혈과부정맥이발생하게된다. 내시경시술중의자율신경계의균형부조화는내시경자체가장관을통과하면서일으키는물리적힘에의한구심성신경 (afferent nerve fiber) 의자극이나불안감에의한스트레스, 내시경중의신경내분비계의변화나내시경을위해사용된약물에의해서도발생한다. 미국소화기내시경학회의보고에의하면내시경중에발생하는심장및호흡기부작용의약 94% 는내시경술기자체보다는동반되어사용되는 benzodiazepine계통의진정제나마약성진통제에의한것으로알려졌다. 4 이러한약제들은자율신경계에영향을미치는것으로알려져있다. 내시경시술중에관찰되는혈역동학적 (hemodynamic) 변화는장관내의내시경의위치, 내시경의직경등에물리적자극에영향을받는다. 상부내시경중에서는내시경이식부에위치하게되면구심성신경을통해서미주신경의감쇠반사 (vagal withdrawal reflex) 를유발하여부교감신경에비해교감신경의톤이증가하여빈맥 (tachycardia) 이유발된다. 5 특히하부식도의자극은내장심장반사 (viserocardiac reflex) 를통해서관상동맥으로의혈류를줄인다. 6 일단내시경이위로진입해서위가공기에의해서확장이되면, 다시교감신경이자극이되게되어빈맥, 혈압상승, 관상동맥혈류감소현상이나타나게된다. 7 다음으로중요한사항은내시경을받기전이나시술중에발생하는긴장과스트레스에의한영향을들수있다. 이러한긴장과스트레스는교감신경톤을증가시켜서심장부하를높여서심근허혈이나부정맥을유발할수있다. 이러한긴장과스트레스는개인에따라느끼는정도가매우다르기때문에객관화하기가힘들지만, 심장조영술에서관상동맥질환이증명된사람에게는허혈이나부정맥을일으키는정도가훨씬높다. 8 상부내시경시술중에는저산소증 (hypoxemia) 이오는것으로알려져있고, 원인으로는내시경시술을위한전처치약물, 내시경의신체내위치에따른호흡패턴의변화, 위내용물의흡인등이알려져있다. 9 그러나내시경의물리적특성에의한호흡패턴의변화는일시적이며, 시술이진행함에따라서급속하게교정이된다. 임상적으로문제가되만한저산소증이지속되는 원인으로는진정제, 마약성진정제에의한호흡중추의억제가대부분이다. 한연구에의하면수면이나산소공급을하지않은상태로진단내시경을할경우에는혈중혈당, 코티졸, 에피네프린, 노에피네프린의수치가상승을하며, 상승정도는간단한수술 (minor surgery) 이후에보이는정도와비슷하다고보고되었다. 10 이러한내분비호르몬의변화도심혈관및호흡기에부정적영향을미친다. 다음으로는내시경시술의고위험군에속하는몇가지임상적상황에대해서자세히알아보도록한다. 심근경색 심근경색을비롯한심혈관질환환자에서내시경시술의필요성은적지않다. 실제적으로매년심근경색으로입원한사람의 2% 와 1% 정도에서각각상부위장관출혈과하부위장관출혈이동반된다. 이는심장질환치료를위한항응고제나아스피린투여와연관되어있다. 11 또한대량위장관출혈환자의약 12% 정도는이차적으로급성심근경색이동반되기도한다. 12 다른보고에의하면중환자실이나응급실환자의 30 49% 가관상동맥질환과위장관출혈이동반되어나타날수있으며, 이로인한사망률도 5 10% 에이르는것으로알려져있다. 심근경색이후의환자에게내시경시술을하기위해서는상반된두가지측면을생각해야한다. 첫째, 내시경자체가이전에기술한것과같은이유로해서심혈관및폐기능을악화시켜서심근경색을진행시킬수있다. 둘째로, 심근경색이후의환자에게는지속적인항응고제치료가필수적인데, 이를위해서는현재진행중인출혈병소의확인과치료가필수적이기때문에내시경시술이필요하다는측면이다. 심근경색이후의상부내시경검사의안전성에대한연구결과를살펴보면, 급성심근경색이후에위장관출혈환자에서상부내시경검사는금기는아니며, 심혈관기능이비교적안정적인환자에서는내시경으로인한이점이합병증을능히능가하기때문에비교적안전하게시술될수있다. 심근경색이후에내시경을시행한 180명의환자와대조군 180명을비교한연구에의하면, 심근경색이후에내시경을시행한환자에의전체적인합병증발생률은 7.5% ( 전체 15건중에서 2 건은심각한합병증 ) 로대조군의 1.5% 보다높았다. 그러나 APAHE II (Acute Physiology and hronic Health Enquiry) score가 15점이하인환자에서의합병증은 2%
이상길 : 고위험환자에서의내시경검사 17 로, 16점이상인환자의 21% 에비해서의미있게낮았다. 11 저자들은이연구의결과로임상양상이안정적인심근경색이나협심증환자에서는내시경이안전하다고주장하였다. 그러나이연구에서도수혈, 부정맥이나협심증치료를위한약물투여, 기도삽관이나기계적인공환기등이필요한환자들이다수있었기때문에, 심혈관및심호흡계질환악화를방지하기위한기본적인전처치는필수적이다. 심근경색환자이나협심증환자에게내시경시술을위해서는시술이전에심장및호흡기계의기능에대한평가와자문을거치고, 혈액, 전해질, 산소포화도를교정한상태에서치료내시경술기에익숙하지않은의사보다는숙련된내시경전문의가시행을하는것이좋다. 또한관찰과치료결정에최소한의시간을허비하여빠른시간에끝내도록해야한다. 시술중에는산소를공급하고 pulse oxymetry와 EKG를사용하여감시하는것이바람직하다. 임신부 일반적으로내시경시술의안정성이잘확립되어있는것에반해서임신부에대한내시경시술의안정성에대해서는잘알려져있지않다. 그러나미국통계에의하면매년 12000명, 6000명, 1000명이상의임산부가각각상부내시경, 직장경이나대장내시경, 내시경적역행적췌담도조영술의적절한적응증이되는질환이나상황을접하게된다. 13,14 또한임신중에는내시경시술의대안인방사선학적검사가금기로되어있고, 필요없는약제투여를줄이기위해정확한내시경진단이필요한경우가많으며, 수술을대체할수있는치료내시경에대한선호로인해서내시경시술에대한필요성이높다. 그러나내시경시술은임산부에게있어서몇가지중대한합병증을유발할수있는데, 조기분만, 내시경시술중투여하는약제에의한태아기형, 내시경기기 Table 2. General Principles and Precautions for Gastrointestinal Endoscopy During Pregnancy 14 Endoscopic drugs during pregnancy Use smallest effective dose Involve patients in decisions about potentially fetotoxic drugs When alternative drugs are available, use the drug that is safest to the fetus Avoid category D drugs Do not use category X drugs Avoid optional drugs ontact pharmacologist or perform literature review as necessary regarding drug teratogenicity onsider anesthesiologist referral for administering conscious sedation Other procedure recommendations Defer endoscopy to after first trimester when possible Defer endoscopy to postpartum period when possible (eg, postpone surveillance colonoscopy) Avoid endoscopy for weak indications Terminate poorly-tolerated endoscopic procedures onsider obstetric consultation Fully informed and written consent to include discussion about fetal risks of procedure ontinuous cardiac monitoring and pulse oximetry, and intermittent sphygmomanometry should be performed during procedure onsider fetal monitoring during endoscopy, if available Avoid endoscopy during threatened abortion, placental abruption, or other serious obstetric complications Postpone endoscopy during active labor until postpartum Substitute less invasive procedure if possible: sigmoidoscopy for colonoscopy or possibly MRP for diagnostic ERP Do procedure expeditiously (eg, avoid examination of distal duodenum at EGD or unnecessary endoscopic biopsies) Avoid polypectomy, hot biopsy, or electrocoagulation, if possible Performance of endoscopyby experienced attending endoscopist rather than inexperienced fellow-in-training is strongly preferred onsider performing ambulatory endoscopy in a hospital endoscopy suite rather than private office Avoid fluoroscopy during colonoscopy or EGD, and minimize fluoroscopy during ERP Refer patient with complicated biliary disease during pregnancy to a tertiary medical center
18 대한소화기내시경학회지 2008;36(Suppl. 1):15-20 Table 3. Fetal Safety of Drugs and Other Therapies ommonly Used in Gastrointestinal Endoscopy: Food and Drug Administration ategorization 15 Drug ategory Recommendations during pregnancy Endoscopic premedications Meperidine Diazepam Midazolam Propofol Fentanyl During endoscopy Simethicone Glucagon Ampicillin Gentamicin After endoscopy Naloxone Flumazenil Agents used in selected procedures Polyethylene glycol electrolyte Sodium phosphate solution Diatrizoate Epinephrine Methylene blue Lidocaine Electricity D D D Use in low dose for endoscopy Probably midazolam preferred for endoscopy Use cautiously and in low dose for endoscopy Administration by an anesthesiologist Use in low dose for endoscopy Avoid during endoscopy Avoid during endoscopy except for ERP Use when antibiotic prophylaxis strongly indicated Use when antibioticprophylaxis strongly indicated Avoid. Use only for narcotic overdose Avoid. Use only for benzodiazepine overdose Insufficient data Insufficient data Use minimal dose for therapeutic ERP Avoid unless necessary Insufficient data Patient to gargle and spit out and not to swallow Use electrocautery for therapeutic sphinterotomy, defer for polypectomy during pregnancy Table 4. Indications for Esophagogastroduodenoscopy During Pregnancy 15 Accepted indication in general population Gross acute bleeding Nausea and vomiting Pyrosis Abdominal pain Dysphagia Follow-up of gastric ulcer Guaiac-positive stool iopsy of gastrointestinal mass/ suspected cancer Recommendations for EGD in pregnancy Generally recommended for acute bleeding causing hemodynamic instability or requiring packed erythrocyte transfusions. Generally unnecessary, Nausea and vomiting usually caused by physiologic effects of pregnancy and not mucosal or mural gastrointestinal disease. onsider EGD for atypical situations such as when condition is severe, refractory to therapy, and associated with significant abdominal pain (but not pyrosis). Generally unnecessary. onsider EGD when presentation atypical, severe, and refractory to intense medical therapy. Generally recommended when complications such as dysphagia or gastrointestinal bleeding occur or when esophageal surgery is contemplated. Generally unnecessary. onsider when pain severe or refractory to medical therapy. Generally recommended when complications such as gastrointestinal bleeding occur. May be necessary when cause unknown. Strongly consider when associated with involuntary weight loss. Use judgment and discretion. Strongly consider delay of follow-up EGD for a gastric ulcer that appeared benign by endoscopy and by histopathologic analysis of endoscopic biopsies. onsider endoscopy when associated with iron deficiency anemia if colonic lesion excluded. Generally recommended.
이상길 : 고위험환자에서의내시경검사 19 에의한태반이나태아손상, 심장부정맥, 저혈압, 저환기로인한태아와산모의피해등을들수있다. 특히내시경시술에의한태아의영향은내시경을한시점에서오랜시간이지난뒤에나나타날수있기때문에예방이나평가가힘든경우가많다. 임신중내시경시술의안정성에관한연구가그리적은편은아니나대부분후향적연구이다. 83명의임산부와대조군을비교한전향적연구에서임신중내시경은대조군보다태아나산모에부작용을증가시키지않았다. 15 그러나이연구의결과만으로임신중내시경이절대적으로안전하다는것을주장하기에는미약한점이많다. 임신중에내시경을하기위해서는몇가지점을숙지하여야한다 (Table 2). 15 일단통상적으로내시경시술에사용되는약제가임산부와태아에미치는영향을숙지하여야하며 (Table 3), 만약사용하여야할경우에는최소량을사용하고, 태아에게무해한것으로대체하거나, category D나 X에해당하는약은피하여야한다. 가급적임신첫 3개월간 (first trimester) 에는내시경을피하고, 반드시필요한적응증일경우에만 (Table 4) 15, 산부인과전문의의의뢰를거친이후에시행하는것이바람직하다. 고 최근에들어서고령인구가증가함에따라서노인에대한내시경수요가늘어나고있다. 65세이상을노령으로규정하고 80세이상을초고령으로정의할때에, 이들에대한내시경시술때에합병증이더많다는증거는없다. 16 그러나노인환자들은기존에심혈관혹은호흡기질환을이미가지고있을가능성이높기때문에, 우발적인상황이일어날개연성이있다. 실제로건강한노인의상부내시경중에심전도상의변화는젊은연령에비해 2배정도자주일어난다. 17 또한심각한우발증으로연결되는경우는드물지만, 초고령의환자를대상으로상부내시경을하였을때, 부정맥이많이발생하였고, 특히기존에심장질환이있는환자에서많이발생하였기때문에, 내시경을한직후부터일정시간까지의관찰이필요하다는주장도있다. 18 미국소화기내시경학회의가이드라인에서는노인환자에서내시경은일반인과같은적응증으로시행될수있으나, 내시경전처치중에혈액이나전해질불균형이올가능성이높기때문에주의를해야하며, 수면내시경시에는가급적적은양을초회에사용하도록하 령 고수면정도가깊지않게유지하도록권고하고있다. 결 상부내시경을비롯한내시경시술은안전하고정확한시술임에는틀림이없다. 내시경으로인한우발증의대부분이심혈관및호흡기계합병증임을볼때에고위험군의환자에게내시경을할때에는내시경중에적절한산소포화도와심전도의감시, 진정및수면의최소사용이나회피, 산소공급등이기본적으로동반되어야한다. 또한추후발생할수도있을법적인문제를대비하여적절한적응증에대해서만시행하고, 심장내과 / 호흡기내과 / 마취과 / 산부인과등에대한내시경시술에대한협진을거치는것이좋을것이며, 시행시에는충분한설명이후에동의서를받고시술및시술이후의감시에대해서올바른기술을남기는것이중요할것이다. 론 참고문헌 1. Levin TR, Zhao W, onell, et al. omplications of colonoscopy in an integrated health care delivery system. Ann Intern Med 2006;145:880-886. 2. Lieberman DA, Wuerker K, Katon RM. ardiopulmonary risk of esophagogastroduodenoscopy. Role of endoscope diameter and systemic sedation. Gastroenterology 1985;88:468-472. 3. Schwartz PJ, La Rovere MT, Vanoli E. Autonomic nervous system and sudden cardiac death. Experimental basis and clinical observations for post-myocardial infarction risk stratification. irculation 1992;85:91. 4. Arrowsmith J, Gerstman, Fleischer DE, enjamin S. Results from the American Society for Gastrointestinal Endoscopy/U.S. Food and Drug Administration collaborative study on complication rates and drug use during gastrointestinal endoscopy. Gastrointestinal Endoscopy 1991;37:421-427. 5. hristensen M, Milland T, Rasmussen V, Schulze S, Rosenberg J. EG changes during endoscopic retrograde cholangiopancreatography and coronary artery disease. Scandinavian Journal of Gastroenterology 2005;40:713-720. 6. hristensen M, Rasmussen V, Schulze S, Rosenberg J. Vagal withdrawal during endoscopic retrograde cholangiopancreatography. Scandinavian Journal of Gastroenterology 2000;35: 96-101. 7. Rossi P, Andriesse GI, Oey PL, Wieneke GH, Roelofs JM, Akkermans LM. Stomach distension increases efferent muscle sympathetic nerve activity and blood pressure in healthy humans. Journal of the Neurological Sciences 1998;161:148-
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