腎臟內 科 實 證 閱 讀 報 告 EBM-style Journal Reading 報告人： PGY吳佳叡 指導臨床教師：Attending 邱炳芳醫師 地點：洗腎室討論室

Basic Data Name：曾X偵 Gender：Woman Age： 33y/o Chart No.：2**37**5 Admission Date：6/7/2011

Chief Complaint Suicide by burning charcoal

Present illness She suffered from suicide by burning charcoal in hotel since 5 hour ago this morning. Consciousness loss, headache and dizziness were noted form then. Transfer to our ER from 秀傳.

Lab Data Carboxyhemoglobin (CO-Hb) 12.9 % Troponin-I 19.14 CPK 7445 12.9 % Troponin-I 19.14 CPK 7445 CPK-MB 186.5 WBC 20900 GPT 97 Cr 1.21 PH 7.443 PCO2 18.1 PO2 273.5 Base Excess -8.1 HCO3 12.5 O2 99.9

Clinical Scenario （臨床情境） 一名33歲女性,被人發現於旅館中昏迷不醒,現場有異味,懷疑燒炭,送醫後,於急診抽血報告,發現血中CO-Hb12.9%偏高,疑為一氧化碳中毒.心臟酵素(Tropinin-I:19.14, CPK7445, CKMB:186.5)有明顯升高.動脈血檢驗pH: 7.443, Base Excess: -8.1. WBC: 20.9 腦部電腦斷層無明顯異狀, 經與家屬訪談,病人最近情緒不甚穩定,有多次自殘自殺經驗. 住院接受進一步治療與觀察.

Type of Question: Therapy 臨床個案的PICO Patient / Problem Carbon monoxide poisoning Intervention Hyperbaric oxygen Comparison Normal baric oxygen Outcome Type of Question: Therapy

INTRODUCTION Carbon monoxide (CO) is an odorless, tasteless, colorless, nonirritating gas formed by hydrocarbon combustion Carbon monoxide (CO) diffuses rapidly across the pulmonary capillary membrane and binds to the iron moiety of heme (and other porphyrins) with approximately 240 times the affinity of oxygen

Clinical findings of CO poisoning The clinical findings of CO poisoning are highly variable and largely nonspecific. Headache (most common) Malaise, nausea, dizziness, Alterations in mental status, from mild confusion to seizures and coma Cardiac ischemia

Diagnosis History and physical examination Carboxyhemoglobin level. Acid-base status on blood gas EKG, cardiac enzyme CNS imaging Pulse oximetry is unable to distinguish

Management (Grade 1B) Removal from the source of CO 100 percent oxygen by non-rebreathing face mask or endotracheal tube. Diagnosis and Treatment of Human Poisoning, 2nd ed, Williams & Wilkins, Baltimore, 1997. J

Treatment with HBO (Grade 2B): CO level >25 percent CO level >20 percent in pregnant patient Loss of consciousness Severe metabolic acidosis (pH <7.1) Possible end-organ ischemia (eg, EKG changes, chest pain, altered mental status) J Emerg Med. 1995;13(2):227

Contraindication Absolute: untreated pneumothorax. Relative :obstructive lung disease, upper respiratory or sinus infections, recent ear surgery or injury, fever, and claustrophobia. Highest risk: Pregnancy ,history of a seizure disorder, pneumothorax, or chest surgery

COMPLICATIONS Reversible myopia Symptomatic otic barotrauma Pulmonary barotrauma Pulmonary oxygen toxicity Seizures due to central nervous system oxygen toxicity

Type of Question: Therapy 臨床個案的PICO Patient / Problem Carbon monoxide poisoning Intervention Hyperbaric oxygen Comparison Normal baric oxygen Outcome Type of Question: Therapy

Search Terms & Strategy: （搜尋關鍵字與策略） 資料庫：PubMed 搜尋日期：1000610 搜尋關鍵字與隅策略： #5 Search delayed encephalopathy after acute carbon monoxide poisoning08:59:5930 #4 Search ((#1) AND #2) AND #308:59:191 #3 Search encephalopathy08:58:5932425 #2 Search hyperbaric oxygen08:58:267385 #1 Search carbon monoxide poison08:57:43697

Best available evidence: （挑選可獲得之最佳研究證據） Citation/s: Factors affecting the prognosis of patients with delayed encephalopathy after acute carbon monoxide poisoning Lead author's name and fax: American Journal of Emergency Medicine (2011) 29, 261–264

DEACMP Delayed encephalopathy after acute carbon monoxide poisoning (DEACMP) is a group of neuropsychologic disorders that occur days or weeks later after the disappearance of the symptoms of acute carbon monoxide (CO) poisoning

Risk factors for Cognitive Sequelae Am J Respir Crit Care Med, 2007

Hyperbaric oxygen (HBO) treatment has been suggested to reduce incidence of DEACMP when used at acute CO poisoning phase But it remains unclear if HBO2 is useful in treating DEACMP when used at a late phase after the development of DEACMP

Subjects Retrospective study included 46 DEACMP patients(2005 to 2008). Clear history of acute CO poisoning, a distinct “lucid interval, and neuropsychologic symptoms, such as dementia First-time admittance to a hospital (within 1 week of onset of disease) At least a standard treatment period was completed in our hospital.

Treatments The HBO2 treatment was given to all patients. Patients were placed in a multiplace chamber pressurized with compressed air; treating pressure was 0.2 MPa (2 ATA)with 100% O2 through a face mask for 60 minutes (which is defined as 1 HBO2 session) The total numbers of HBO2 sessions received by the patients were 24 to 82 (49.2 ± 25.5 sessions).

Prognosis factor Age Sex Fundamental diseases HBO2 treatment in acute stage Intoxication time, Unconsciousness duration Lucid interval Danger-ADL scores, Complications Monosialoteterahexosyl Ganglioside treatment(GM1 ganglioside administration.)

Assessment of treatment The treatment effects of the 46 patients were assessed approximately 2 months after the onset of DEACMP. Improvement group : ADL score higher than 60 points and were capable of simple verbal communication, independent eating, walking, and using toilet with independent daily life. Non improvement group had an ADL score less than 40 points and were incapable of verbal communication with completely dependent daily life.

The Evidence: （研究重要結果） The major findings of the study are that HBO2 treatment is useful in treating DEACMP age, lucid interval, danger-ADL scores, and complications are important factors affecting the prognosis of DEACMP patients. The results show that patients with greater age and less danger-ADL scores are more likely to have a bad prognosis.

Comment & Discussion: -1 因為研究只有三年,所以樣本數還是過少(46人) 實驗方法沒有對照組,而是採用回溯性研究,以因果原因來推斷高壓氧的治療效益,邏輯推理上似乎令人較難完全信服. 探討遲發性腦病變,以ADL來評斷,如果能加上影像學上的對照,對結果是否有幫助? 最終的ADL分數作評斷標準,而不是以ADL治療前後差異?

Comment & Discussion: -2 追蹤時間兩個月,因為病人的重要器官損傷,後遺症或許會更久才顯現出來. 除了腦部病變外,也可以往心肺的後遺症作探討.

Comment & Discussion: -3 Hyperbaric oxygen therapy for acute domestic carbon monoxide poisoning: two randomized controlled trials 排除自殺個案 時間追蹤一個月 病人一定要陷入昏迷 ★高壓氧對CO中毒病人並無幫助 Am J Respir Crit Care Med, 2007

Comment & Discussion: -4 Carbon Monoxide PoisoningRisk Factors for Cognitive Sequelae and the Role of Hyperbaric Oxygen 追蹤6週.6,12個月各評估一次 評斷標準較為主觀(說故事,記憶力) 高壓氧對昏迷跟CO-Hb高的病人是有幫助的 Lindell K., Am J Respir Crit Care Med, 2007

Clinical bottom line 臨床決策底線 回到臨床個案情境 Clinical bottom line 臨床決策底線 證據等級IIc, 在急性期以高壓氧治療對遲發性腦部病變有幫助.

References: Hyperbaric oxygen therapy for acute domestic carbon monoxide poisoning: two randomized controlled trialsDjillali Annane Intensive Care Med (2011) 37:486–492 Carbon Monoxide PoisoningRisk Factors for Cognitive Sequelae and the Role of Hyperbaric Oxygen Lindell K., Am J Respir Crit Care Med Vol 176. pp 491–497, 2007

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