跟讀練習: Introduction to ECMO Part 3 - V-A ECMO - 通過影片學習英語口語
選擇練習模式
每種模式都會開啟全屏練習室。
93 句
如果句子過短或過長，請點選 Edit 進行調整。
1
Veno-arterial ECMO is a bit like Veno-Venous ECMO, except you return the non-pulsatile blood flow into a high pressure system.
2
Oh, and the blood is travelling in the wrong direction.
3
My name is Ken Hoffman.
4
I'm an intensivist at the Alfred Hospital in Melbourne.
5
This is the third video in our introduction to ECMO series, aimed at new staff joining our team.
6
It will cover the principles of Veno-arterial or VA ECMO,
7
the indications, complications and considerations for liberation from VA ECMO support.
8
To start with, the circuit itself for VA ECMO is very similar to VV ECMO.
9
The major difference is that blood is returned to an artery under high pressure.
10
In this way, we can consider the ECMO pump being an artificial heart pumping non-pulsatile blood in parallel around the body.
11
The circuit starts with an access cannula in the right atrium or vena cava which removes venous blood from the body.
12
As this blood will return to the arterial circulation without going through the lungs, it must pass through a membrane oxygenator for gas exchange.
13
It will then be returned back under high pressure to the arterial circulation, usually via the common femoral artery.
14
The returning blood travels in the opposite direction through the arterial system, back towards the heart.
15
If the heart is still able to contract and eject some blood, this blood will mix with the ECMO blood somewhere in the proximal aorta.
16
This combination of a native pulsatile circulation and an artificial retrograde non-pulsatile circulation will be important when considering some specific complications later.
17
One specific difference with a VA ECMO circuit is the requirement for a backflow cannula.
18
As the large return cannula will sit in the common femoral artery, this can occlude blood flow to the leg.
19
To prevent leg ischemia, a smaller cannula is placed in the superficial femoral artery
20
which is connected into the ECMO circuit and allows downstream perfusion of the leg with oxygenated ECMO blood.
21
To titrate the amount of VA ECMO flow, we rely on clinical parameters such as mean arterial pressure,
22
lactate, urine output and peripheral perfusion.
23
Turning up the fresh gas flow doesn't really change the oxygen delivery.
24
So if the patient needs more support, the ECMO circuit flow should be increased.
25
It is important to remember that with VA ECMO, the fresh gas flow should never be turned to zero,
26
as this would result in deoxygenated blood being returned into the arterial circulation.
27
To summarise, VA ECMO can provide cardiac support by pumping oxygenated blood into the arterial circulation.
28
It can also be used for respiratory support as the returned blood is fully oxygenated.
29
In terms of the indications for VA ECMO, it is used as support for severe heart failure.
30
It is important to remember that VA ECMO doesn't actually fix anything.
31
Instead, it provides time so the patient can be bridged to recovery, bridged to a durable left ventricular assist device, or transplantation.
32
This is why VA ECMO is still a niche support modality.
33
A lot of the complexity comes from decision-making about how and when to liberate the patient from VA ECMO support.
34
The next thing to talk about are complications.
35
These can be divided into the common ECMO complications of bleeding,
36
thrombosis, infection and hemolysis and specific VA ECMO complications.
37
The specific VA ECMO complications to discuss are differential hypoxia,
38
left ventricular distension, leg ischemia and cardiac arrest on VA ECMO support.
39
Differential hypoxia occurs as a result of mixing between the forward flowing native cardiac output and retrograde flow from the ECMO circuit.
40
If the native lungs are poorly oxygenating the native cardiac output, then hypoxic blood will be pumped into the aorta.
41
The relative proportions of native cardiac output to ECMO flow will determine where the mixing point will be in the aortic arch.
42
If native heart function improves but the lungs still have respiratory failure, increasing amounts of hypoxic blood will enter the arterial circulation,
43
which will disproportionately affect the upper parts of the body.
44
In order to detect this, the arterial line is routinely inserted in the right radial artery
45
and the pulse oximeter should be placed on the right hand or right ear lobe.
46
This will confirm if the blood in the first branch of the aortic root, which is the brachiocephalic trunk,
47
is delivering adequately oxygenated blood to the right subclavian artery and more importantly, the right common carotid artery.
48
When differential hypoxia occurs the focus should be on trying to
49
improve the native lung function to increase oxygenation of the native cardiac output.
50
Other options include reducing inotropy to decrease the native cardiac output,
51
increasing ECMO flow to move the mixing point proximally or reconfiguring to return sites other than the femoral vessels.
52
Rarely fancy ECMO modes are required such as VAV or even separate VA and VV ECMO circuits.
53
Next complication to talk about is left ventricular distension.
54
This occurs
55
when the left ventricle is unable to generate enough tension for
56
the aortic valve to open during systole due to the pathology affecting the ventricle plus the increased afterload from retrograde ecmine flow.
57
This is exacerbated by any aortic valve regurgitation.
58
When left ventricular distension occurs,
59
the forward flow through the lungs is impaired and can result in pulmonary edema and pulmonary hemorrhage.
60
Rarely, stagnant blood in the left ventricle can clot.
61
Signs of left ventricular distension include a loss of arterial line pulsatility, a chest x-ray with pulmonary edema
62
or an echo with a dilated poorly functioning left ventricle with an aortic valve that is not opening.
63
Management of left ventricular distension involves increasing left ventricular ejection with inotropes,
64
reducing peripheral resistance and lowering mean arterial pressure targets and fluid removal to reduce the main systemic filling pressure.
65
If these interventions don't work, the left ventricle needs to be decompressed.
66
Usually, this is with a left ventricular vent cannula, which is joined into the access part of the ECMO circuit and drains the left ventricle with negative pressure.
67
The complication of leg ischemia has already been discussed.
68
It is prevented with insertion of a backflow cannula in the superficial femoral artery.
69
The leg still requires regular vascular observation by monitoring non-pulsatile Doppler flow as the backflow cannula can develop thrombosis.
70
The last complication to discuss is cardiac arrest on VA ECMO.
71
This is detected by a loss of pulsatility on the arterial line and an ECG that is not in a perfusing rhythm.
72
When this occurs, chest compressions are not required.
73
Instead, attempt to increase the VA ECMO flow to provide support whilst trying to restore a perfusing rhythm.
74
The reason restoring a perfusing rhythm is important is that stagnant blood in the left ventricle may clot.
75
Large clots in the left ventricle are unsurvivable.
76
and even small clots may result in embolic complications with restoration of cardiac output.
77
The final thing to discuss is liberation from VA ECMO support.
78
As already mentioned, if there is no cardiac recovery, then ECMO is a bridge to another treatment,
79
such as a durable left ventricular assist device or transplantation.
80
If there is cardiac recovery, then an echo-guided weaning study is performed.
81
This examines cardiac function with progressively reducing VA ECMO flow to determine
82
if the heart is able to cope without VA ECMO support.
83
If the weaning study is passed,
84
the VA ECMO is removed in the operating theatre as the large arterial cannulation site requires some stitches to control bleeding.
85
In summary, VA ECMO is used for cardiac support when the heart is unable to pump sufficient blood to maintain organ function.
86
Complications occur related to the ECMO circuit including the VA specific complications of differential hypoxia and left ventricular distension.
87
Liberation from VA ECMO is complicated as it is used either
88
as a bridge to recovery guided by an echo weaning study
89
or as a bridge to a durable left ventricular assist device or transplantation.
90
If you would like to read more about our ECMO protocols, they are freely available at ecmo.icu.
91
Thank you for listening.
92
If you enjoyed this video, please hit the like button.
93
If you would like to see more videos like this, please subscribe to our channel.
FOR YOU
推薦影片
C12
17 句
Robotic Neurovascular Intervention
Daily ConversationUniversity StudentsWorking Adults
C12
33 句
ELSO Interim Guidelines for Adult Venoarterial ECMO
IELTS PrepTOEFL PrepUniversity Students
C11
91 句
How To: Ultrasound for Pneumothorax Case Study Video
Daily ConversationUniversity StudentsWorking Adults
C11
150 句
Parallel Pump Operation
Daily ConversationUniversity StudentsWorking Adults
C113
202 句
SAC | Soft Actor Critic (SAC) architecture | SAC Explained
Daily ConversationUniversity StudentsWorking Adults
C16
384 句
Dr. Andy Galpin: Does Cardio Ruin Muscle Growth?.
Daily ConversationUniversity StudentsWorking Adults
C15
34 句
SVINutes: Decoding Dizziness
Daily ConversationUniversity StudentsWorking Adults
B21
15 句
How does acupuncture work? | RMIT University
Daily ConversationUniversity StudentsWorking Adults
C11
154 句
Sequential, Multiple Assignment, Randomized Trial Designs With Dr Kidwell
Daily ConversationUniversity StudentsWorking Adults
C11
64 句
What is SCADA?
Daily ConversationUniversity StudentsWorking Adults
C11
4 句
Ambr®️ 250 High Throughput Perfusion Product Tutorial - Learn with Sartorius
Business EnglishUniversity StudentsWorking Adults
C14
153 句
The Neuroscience of Love and Attachment: Oxytocin, Vasopressin, and Dopamine's Role in Bonding
Daily ConversationUniversity StudentsWorking Adults
背景與上下文
在這段影片中，Ken Hoffman醫生是一位在墨爾本Alfred醫院工作的重症監護醫生，他介紹了Veno-arterial ECMO（VA ECMO）的基本原理、適應症、併發症以及如何從VA ECMO支援中解脫。VA ECMO是一種給心臟提供支援的方法，通過向動脈迴圈中注入氧合血液，幫助那些面臨嚴重心力衰竭的患者。瞭解這些內容不僅對醫學專業人員有幫助，也為希望通過這段影片提高英語口語能力的學習者提供了一種實際的學習方式。
日常交流中的五個關鍵短語
- “the circuit itself for VA ECMO” - VA ECMO的迴路本身
- “artificial heart pumping non-pulsatile blood” - 人工心臟泵送非脈動血液
- “prevent leg ischemia” - 防止腿部缺血
- “titrate the amount of VA ECMO flow” - 調節VA ECMO流量的多少
- “important when considering some specific complications” - 考慮某些特定併發症時的重要性
逐步影子練習指南
為了有效提高你的英語口語能力，特別是通過這個VA ECMO的錄影，以下是一個逐步的影子練習指南：
- 第一次觀看：觀看影片時，專注理解主要內容，不用考慮每一個單詞。在這個過程中，你可以選擇記錄下不懂的單詞或短語。
- 第二次觀看：這次要嘗試跟隨影片中的語音，你可以嘗試用“shadow speech”方法，模仿Ken醫生的語音和語調。這種“影子講話”的練習有助於提升你的口語流利度和語音準確性。
- 重複播放關鍵短語：對於你在“日常交流中的五個關鍵短語”中列出的短語，反覆練習它們的發音和使用場景，將它們融入你的口語中，提升你的雅思口語練習水平。
- 實地應用：尋找機會與他人交流時使用這些短語，無論是在專業討論還是日常對話中，都能讓你更自然地運用英語。
- 自我評估：錄音再聽回自己講述時，注意發音，語速和語調。你可以在自己的學習記錄中記錄進展，並逐漸增強自信。
通過這種影子練習方式，你能夠有效地提升你的英語會話能力，尤其是在醫學領域的專業英語使用上。記得多看YouTube學英語，讓你的學習更高效！
影片中的語法
說話人最常用的結構，並附上影片中的原話：
| 結構 | 影片中的用法 |
|---|---|
| 被動語態 be + 過去分詞 — 強調發生了什麼，而不是誰做的 | is returned · be returned · is placed |
| 定語從句 who / which + 從句 — 補充說明人或事物 | root, which is · cannula, which is |
什麼是跟讀法？
跟讀法 (Shadowing) 是一種有科學依據的語言學習技巧，最初開發用於專業口譯員的培訓，並由多語言者Alexander Arguelles博士普及。這個方法簡單而強大：您在聽英語母語原聲的同時立即大聲重複——就像是一個延遲1-2秒緊跟說話者的影子。與被動聽力或語法練習不同，跟讀法強迫您的大腦和口腔肌肉同時處理並模模擬實的講話模式。研究表明它能顯著提高發音準確性，語調，節奏，連讀，聽力理解和口語流利度——使其成為雅思口語備考和真實英語交流最有效的方法之一。