Review article https://doi.org/10.22470/pemj.2018.00290 pissn: 2383-4897 / eissn: 2508-5506 소아응급실내진정및진통요법 김도균 서울대학교병원응급의학과 Procedural sedation and analgesia in pediatric emergency department Do Kyun Kim Department of Emergency Medicine, Seoul National University Hospital, Seoul, Korea The frequency of procedures in the emergency department has increased with changes in the medical environment and the demands of the times. Especially in children, sedation and analgesia are often inevitable due to the difficulty in seeking cooperation. Procedural sedation and analgesia is essential for successful completion of procedure, but the medical personnel who perform it must be prepared for complications caused by medications. Safe procedural sedation and analgesia requires well-trained medical personnel and well-prepared equipment, including appropriate patient assessments and choice of medications, faithful monitoring, and resuscitation. This review focuses on understanding of sedation processes, patient evaluation, medications, and monitoring. Key words: Analgesia; Anesthesia; Conscious Sedation; Deep Sedation; Pain, Procedural; Pediatric Emergency Medicine 서 론 1. 소아응급실내진정및진통요법 (procedural sedation and analgesia, PSA) 의특수성 응급실은제한된시간, 인력, 장비, 공간을이용하여환자의문제점을파악하고해결해야하는특수한환경의의료공간이다. 응급실환자의약 25% 를차지하는소아응급 Received: Nov 16, 2018 Revised: Nov 26, 2018 Accepted: Nov 26, 2018 Corresponding author Do Kyun Kim (ORCID 0000-0002-6144-302X) Department of Emergency Medicine, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul 03080, Korea Tel: +82-2-2072-0238 Fax: +82-2-3676-4839 E-mail: birdbeak@naver.com 환자 ( 소아환자 ) 는낯선응급실에서진단과치료에필요한시술및검사에협조하기어려워, PSA가필요한경우가많다. 그러나응급실의한정된의료자원으로인해환자평가및감시가불충분하여, 합병증발생시제대로대처하지못하기도한다. 특히소아환자는약의치료범위 (therapeutic range) 가좁아예정보다깊은진정으로빠지기쉽다. 이는성인에비하여해부 생리학적으로취약한호흡계를가진소아에서심각한합병증발생을유발할수있는위험중하나이다. 2. 진정의정의및깊이진정이란, 환자가처치시통증을느끼지않도록의식저하를유도하나스스로호흡을유지할수있는정도를의미한다. 수술보다소요시간이짧고통증이적은술기에적용하므로, 긴시간동안환자의호흡을억제할정도로깊게재우는마취와는확연히구분된다. 진정깊이는 3단 31
계 ( 얕은, 중등도, 깊은진정 ) 로구분하며, 진정이깊어질수록호흡및순환에미치는영향이커진다. 진정깊이는환자상태와술기관련통증정도, 소요시간등을고려하여계획한다. 진정의각깊이는뚜렷이구분하기어려운하나의연속선상에있어, 흔히예정보다깊거나얕게진정될수있음에주의해야한다. 본론 1. 진정전단계 1) 진정전환자평가및준비 PSA의첫단계는환자평가이다. AMPLE 등의도구를이용하여병력을청취한다. 이도구의이름은 A (allergy), M (medication), P (past medical history), L (last meal), E (event) 로이루어진두문자어로, 병력청취의필수요소를누락하지않도록도와준다. 또한, 과거력을확인해미국마취과학회 (American Society of Anesthesiologists) 분류를확인한다 (Table 1) 1). 대개 1, 2단계는저위험군, 3, 4단계는고위험군으로분류하며, 고위험군에서기도폐쇄와같은중대한합병증발생가능성이높다는점을알고있어야한다. 약의금기에해당하는병력과선천얼굴기형과같이처치에어려움을주는징후를파악한다. 2) 금식응급실진정에서금식기준은곤란한문제이다. 여러진정및진통요법지침이미국마취과학회수술전금식기준 2) 을준용하는실정이지만, 응급실에서소아환자에게이 기준을엄격하게적용하긴어렵다. 최근시행된소아환자대상의두개의대규모다기관연구 ( 한연구는응급실소아환자를대상으로함 ) 에따르면, 두연구결과모두진정전금식기준을지킨군과그렇지못한군사이에주요합병증발생빈도에차이가없었다 3,4). 실제로, 미국응급의학회 (American College of Emergency Physicians) PSA 지침은응급시술이필요한환자에서금식상태는고려대상이아니라는점을강조한다 5). 소아환자진정에서금식기준에대한새로운합의가필요하다. 3) 인력진정시술자외에진정자체를관리및감시하는인력이한명이상필요하며, 이는 PSA 지침에서필수적인기준이다. 한명의시술자가진정까지담당하면, 시술에집중하느라환자감시에소홀할수있기때문이다. 응급실인력이부족한한국상황에서이기준을준수하기는쉽지않으나, 진정의가장중요한항목이환자감시및합병증대처임을이해하고노력해야한다. 진정담당인력은진정제및진통제의특성과작용기전을잘이해하고, 환자평가및감시에능숙하며, 합병증발생시적절히대처할수있고, 나아가전문소아소생술 ( 특히, 기도관리 ) 에능숙해야한다. 4) 장비진정전장비확인은필수적이다. 장비확인절차는 SOAP- ME, 즉 S (suction: 흡인기구 ), O (oxygen: 산소및산소투여장비 ), A (airway: 기도유지장비 ), P (pharmacy: 약 ), M (monitoring: 감시장비 ), E (Extra-equipment: 정맥내주사및제세동기 ) 로알아두면좋다. 응급실외에다 Table 1. The ASA physical status classification system ASA class Definition Example I A normal healthy patient Unremarkable medical history II A patient with mild systemic disease (no Mild asthma, controlled seizure disorder, anemia, functional limitation) and controlled DM III A patient with severe systemic disease (definite Moderate to severe asthma, poorly controlled seizure, functional limitation) pneumonia, poorly controlled DM, and moderate obesity IV A patient with severe systemic disease that is Severe BPD, sepsis, and advanced degrees of a constant threat to life pulmonary, cardiac, hepatic, renal or endocrine insufficiency V A moribund patient who is not expected to survive Severe cardiomyopathy requiring heart without the operation transplantation Modified from https://www.asahq.org/standards-and-guidelines/asa-physical-status-classification-system 1). ASA: American Society of Anesthesiologists, DM: diabetes mellitus, BPD: bronchopulmonary dysplasia. 32 Pediatric Emergency Medicine Journal
진정및진통요법 른장소 ( 예 : 컴퓨터단층촬영실 ) 로이송하여진정을시행할수도있으므로, 실제진정이시행되는장소에장비를갖추는것이중요하다. 2. 진정단계 1) 환자감시얕은진정및중등도진정은맥박산소측정기로산소포화도와심장박동수를확인하는것으로충분하다. 반면, 깊은진정은안전한시술을위해, 추가로심전도, 혈압, 호기말이산화탄소분압을감시해야한다 6). 저환기발생후산소포화도감소까지는어느정도시간이걸리는데, 호기말이산화탄소분압감시는이를조기에확인할수있어깊은진정, 고위험군, 두종류이상의약반복투여시유용한감시도구이다. 실제 propofol을이용한진정대상연구에서호기말이산화탄소분압감시사용이저산소증발생사례를유의하게감소시킨결과가보고된바있다 7). 2) 합병증대처진정과정에서기도와호흡관련합병증이가장많다. 주로혀근육이완으로인한기도폐쇄와중추성호흡억제가대부분이며, 일반적인기도유지, 분비물흡인, 산소요법으로호전된다. 성문연축은드물게발생하지만, 초기에대처하지못하면치명적인결과를초래할수있다. 특히소아환자에서많이사용하는 ketamine은성문연축발생빈도가다른약보다높아 (0.3%-0.5%) 8), 발생시응급처 치방법을숙지해야한다. 성문연축발생의위험인자는상기도감염, 다른진정제또는항콜린제병용, 후두후벽을자극하는시술 ( 예 : 위내시경 ) 등이다. 성문연축발생시턱들어올리기와 Bag-Valve-Mask Ventilation을이용한양압환기로대부분해결할수있으며, 양쪽성문연축패임 (laryngospasm notch) 을동시에세게누르는방법이유용할수있다 9). 위방법에호전되지않으면빠른연속기관삽관 (rapid-sequence intubation) 이필요하므로, 의심되면반드시도움을요청하고필요한약을준비한다. 합병증발생은예측이어렵고낮지만, 일정한빈도 ( 예를들어 ketamine 사용때기도와호흡기관련합병증발생은약 4%) 로발생한다. 따라서합병증에대한감시와신속정확한대처가필요하다. 3) 진정후환자관리및귀가기준진정제를사용한시술이끝난후진정효과가지속하는동안환자감시를계속해야한다. 소아환자진정합병증중시술후발생하는비율이약 8% 정도로알려져있다 10). 응급실에서 PSA를경험한환자의귀가기준으로는 modified Aldrete scoring system이가장많이쓰이며총 9점이상이면귀가할수있다 (Table 2) 11). 귀가시, 주의사항과연락처를적은안내문을준다 (Appendix 1). 4) 대표적진정제및진통제 a. Ketamine 진정및진통효과를모두가지며소아에서사용경험이 Table 2. The modified Aldrete scoring system Subject Content Score* Activity Able to move all extremities voluntarily on command 2 Able to move 2 extremities voluntarily on command, some weakness 1 Unable to move extremities 0 Respiration Able to breathe deeply and cough without assistance 2 Requires airway assistance 1 Apnea 0 Circulation Blood pressure ± 20% of pre-sedation level 2 Blood pressure ± 20%-49% of pre-sedation level 1 Blood pressure ± 50% of pre-sedation level 0 Consciousness Fully awake, able to answer questions as appropriate 2 Arousable with verbal stimulation 1 Unresponsive 0 Oxygenation Able to maintain O 2 saturation > 92% on room air 2 Requires supplemental O 2 to maintain O 2 saturation > 90% 1 O 2 saturation < 90% even with supplement O 2 0 Modified from Aldrete. J Clin Anesth 1995;7:89-91, with permission of Elsevier 10). * A total score 9 is required for discharge. Pediatric Emergency Medicine Journal 33
장기간축적되어응급실에서가장많이사용하는약중하나이다. Ketamine은대뇌피질기능을억제하면서변연계기능을촉진하여, 해리진정제 (dissociative sedative) 로분류한다. 독특한기전만큼다양한부작용이나타나므로금기기준을숙지해야한다 12). 나이 3개월미만 ( 기도합병증위험증가, 뇌발달에영향 ) 과조현병 ( 조절여부무관 ) 은절대적금기이다. 상대적금기로는인두후벽을자극할수있는시술 ( 구강내검진제외 ), 기도수술력, 기관지협착, 호흡기감염, 심혈관계질환, 신경계종양, 수두증, 녹내장, 급성안구손상, 포르피린증, 갑상선질환이알려져있다. 최근연구들에의하면두부외상또는뇌수술환자에서 ketamine 사용이유의하게두개내압을올리지않는다고보고되었다 13-15). 이결과는 ketamine의주요부작용으로알려졌던두개내압상승에대해재고할필요성을제시한다. 실제미국소아과학회 (American Academy of Pediatrics) 의 PSA 교과서에서도, 약간의호흡양상의변화에도두개내압이영향을받을수있는상황 ( 두부종양으로인한뇌압상승등 ) 의경우를제외하고는 ketamine 사용을주저할필요가없다고기술하였다 16). Ketamine 자체는심장수축력을감소시키지만교감신경을자극하는기전으로인해, 전체적으로는혈압과심장박동수를증가시킨다. 교감신경자극기전은카테콜아민재흡수억제로추정한다. 따라서카테콜아민이부족한중환자에서는카테콜아민자극효과보다심장수축력감소효과가더클수있어주의가필요하다 8). - 작용발현시간 : 30초 ( 정맥내 ), 5분 ( 근육내 ) - 최대효과시간 : 2-3분 - 지속시간 : 5-10분 ( 정맥내 ), 20-30분 ( 근육내 ), 얕은수면경향은최대 2시간지속 - 용량 : 1-2 mg/kg ( 정맥내 ), 4-5 mg/kg ( 근육내 ) b. Midazolam 응급실에서널리사용하며소아에서사용경험도많다. 기억상실효과가있으나진통효과는없으며, 기도폐쇄와중추성호흡억제가발생할수있다 17). 일부에서탈억제에의한과반응현상 (hyperactivity) 이나타날수있는데, 이경우 midazolam 또는다른진정제를추가투여하거나 flumazenil을사용할수있다 18). 말초정맥내카테터확보없이비강내로투여할수있어사용이증가하고있다 19). - 작용발현시간 : 1-2분 - 최대효과시간 : 2-3분 - 지속시간 : 30분 - 용량 : 0.05-0.1 mg/kg ( 정맥내 ), 0.3-0.5 mg/kg ( 비강내 ) c. Fentanyl 아편유사제로, 작용효과가뛰어나고소아에서사용경험도풍부한편으로진정작용을함께보이는경우가있다. 호흡억제발생에대비해야하며, 특히다른진정제병용시주의해야한다 17). 최근투여방법이비강내및흡입투여등으로다양해지면서재평가되고있다 20,21). - 용량 : 1-2 μg/kg ( 정맥내 ), 1-2 μg/kg ( 비강내 ), 3 μ g/kg ( 흡입 ) - 작용발현시간 : 30초 - 최대효과시간 : 2-4분 - 지속시간 : 20분 5) 한국소아 PSA 지침및교육의필요성소아 PSA에대한한국지침은 2012년대한소아응급의학회의전신인소아응급연구회가발표한 소아를위한술기및진정 : 한국형지침 이시초이다 22). 이후대한소아마취과학회에서 소아진정가이드라인 : 한국형지침 을발표했다 23). 두지침모두소아 PSA에대해체계적인설명과자료를제공한다. 전술한대로, PSA 과정중약부작용및합병증은일정비율로발생한다. 따라서안전한시술이가장중요하며, 예기치못한합병증발생을조기에인지하고대처할수있는지식과기술을익혀야한다. 이에소아청소년과및응급의학과전공의수련목표에소아 PSA 항목을포함해야한다. 교육은이론강의에모의환자시뮬레이션을병행하여진행해야한다. 결론 응급실에서시행하는검사및시술빈도증가와함께, 소아응급실내 PSA 시행이불가피해지고있다. 안전한 PSA를위해서는인력과장비의준비는물론이고환자평가, 약선정, 환자감시, 진정후환자관리및퇴원결정까지의진정전과정이면밀하고꼼꼼하게진행되어야한다. 이중가장중요한요소는이과정을관리하고위기상황에대처하는진정담당인력에대한충분한교육이다. 현재소아진정관련수가가논의중인것은안전한 PSA 에대한의료계안팎의높은요구를반영한결과라고생각 34 Pediatric Emergency Medicine Journal
진정및진통요법 한다. 이수가적용은그만큼진정담당인력에게책임을부여하는의미로해석할수있어, 이를위한인력의교육, 의료자원배치, 질관리에관심을기울여야한다. 재정지원 본저자는이논문과관련된재정지원을받지않았음. 이해관계 본저자는이논문과관련된이해관계가없음. References 01. American Society of Anesthesiologists. ASA Physical Status Classification System [Internet]. Schaumburg (IL): American Society of Anesthesiologists; c2018 [cited 2018 Dec 3]. Available from: https://www.asahq.org/standardsand-guidelines/asa-physical-status-classification-system. 02. American Society of Anesthesiologists Committee. Practice guidelines for preoperative fasting and the use of pharmacologic agents to reduce the risk of pulmonary aspiration: application to healthy patients undergoing elective procedures: an updated report by the American Society of Anesthesiologists Committee on Standards and Practice Parameters.??Anesthesiology 2011;114:495-511. 03. Bhatt M, Johnson DW, Taljaard M, Chan J, Barrowman N, Farion KJ, et al. Association of preprocedural fasting with outcomes of emergency department sedation in children. JAMA Pediatr 2018;172:678-85. 04. Beach ML, Cohen DM, Gallagher SM, Cravero JP. Major adverse events and relationship to nil per os status in pediatric sedation/anesthesia outside the operating room: a report of the pediatric sedation research consortium. Anesthesiology 2016;124:80-8. 05. Godwin SA, Burton JH, Gerardo CJ, Hatten BW, Mace SE, Silvers SM, et al. Clinical policy: procedural sedation and analgesia in the emergency department. Ann Emerg Med 2014;63:247-58.e18. 06. Cote CJ, Wilson S. Guidelines for monitoring and management of pediatric patients before, during, and after sedation for diagnostic and therapeutic procedures: update 2016. Pediatr Dent 2016;38:13-39. 07. Deitch K, Miner J, Chudnofsky CR, Dominici P, Latta D. Does end tidal CO2 monitoring during emergency department procedural sedation and analgesia with propofol decrease the incidence of hypoxic events? A randomized, controlled trial. Ann Emerg Med 2010;55:258-64. 08. Kurdi MS, Theerth KA, Deva RS. Ketamine: current applications in anesthesia, pain, and critical care. Anesth Essays Res 2014;8:283-90. 09. Larson CP Jr. Laryngospasm: the best treatment. Anesthesiology 1998;89:1293-4. 10. Newman DH, Azer MM, Pitetti RD, Singh S. When is a patient safe for discharge after procedural sedation? The timing of adverse effect events in 1367 pediatric procedural sedations. Ann Emerg Med 2003;42:627-35. 11. Aldrete JA. The post-anesthesia recovery score revisited. J Clin Anesth 1995;7:89-91. 12. Green SM, Roback MG, Kennedy RM, Krauss B. Clinical practice guideline for emergency department ketamine dissociative sedation: 2011 update. Ann Emerg Med 2011; 57:449-61. 13. Bar-Joseph G, Guilburd Y, Tamir A, Guilburd JN. Effectiveness of ketamine in decreasing intracranial pressure in children with intracranial hypertension. J Neurosurg Pediatr 2009; 4:40-6. 14. Wang X, Ding X, Tong Y, Zong J, Zhao X, Ren H, et al. Ketamine does not increase intracranial pressure compared with opioids: meta-analysis of randomized controlled trials. J Anesth 2014;28:821-7. 15. Cohen L, Athaide V, Wickham ME, Doyle-Waters MM, Rose NG, Hohl CM. The effect of ketamine on intracranial and cerebral perfusion pressure and health outcomes: a systematic review. Ann Emerg Med 2015;65:43-51.e2. 16. American Academy of Pediatrics Section on Anesthesiology and Pain Medicine. Procedural sedation for infants, children, and adolescents. Tobias JD, Cravero JP, editors. Elk Grove Village (IL): American Academy of Pediatrics; 2016. p96. 17. Pacheco GS, Ferayorni A. Pediatric procedural sedation and analgesia. Emerg Med Clin North Am 2013;31:831-52. 18. Roback MG, Carlson DW, Babl FE, Kennedy RM. Update on pharmacological management of procedural sedation for children. Curr Opin Anaesthesiol 2016;29 Suppl 1:S21-35. 19. Fantacci C, Fabrizio GC, Ferrara P, Franceschi F, Chiaretti A. Intranasal drug administration for procedural sedation in children admitted to pediatric emergency room. Eur Rev Med Pharmacol Sci 2018;22:217-22. 20. Miner JR, Kletti C, Herold M, Hubbard D, Biros MH. Randomized clinical trial of nebulized fentanyl citrate Pediatric Emergency Medicine Journal 35
versus i.v. fentanyl citrate in children presenting to the emergency department with acute pain. Acad Emerg Med 2007;14:895-8. 21. Graudins A, Meek R, Egerton-Warburton D, Oakley E, Seith R. The PICHFORK (Pain in Children Fentanyl or Ketamine) trial: a randomized controlled trial comparing intranasal ketamine and fentanyl for the relief of moderate to severe pain in children with limb injuries. Ann Emerg Med 2015;65:248-54.e1. 22. Jang HY, Jung JH, Kyong YY, Kim KH, Kim DK, Kim MR, et al. Korean guidelines for pediatric procedural sedation and analgesia. J Korean Soc Emerg Med 2012;23:303-14. Korean. 23. Korean Society of Pediatric Anesthesiologist. Pediatric sedation guideline: Korean guideline [Internet]. Seoul (Korea): Korean Medical Guideline Information Center; c2008 [cited 2018 Dec 3]. Available at: Available from: http://www.guideline.or.kr/guide/view.php?number=311& cate=b. Korean 36 Pediatric Emergency Medicine Journal
진정및진통요법 Appendix 1. Example of an instruction letter form used by Seoul National University Children s Hospital for discharged children after the sedation Pediatric Emergency Medicine Journal 37