12 votes
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Why doesn't water enter the venous system if injury happens far underwater?

You're confusing relative and absolute pressures, which is easy to do because we don't usually specify which is meant, the meaning is implied by context. At sea level, atmospheric pressure is around ...
Bryan Krause's user avatar
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9 votes
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Why does breathing stop during cardiac arrest?

During approximately 50% of cardiac arrests, the patient continues to breathe for a time. However, this breathing is known as agonal respiration and is essentially gasping for air. This gasping is ...
L.B.'s user avatar
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8 votes

Can stress increase blood pressure?

tl; dr - The answer is yes, clinically you can react to having your blood pressure (BP) taken by having an abnormally high reading. What you are describing is called "white coat syndrome" or "white ...
JohnP's user avatar
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8 votes

Why patient has to be awake during cardiac catheterization?

There are a couple reasons it's not preferred. The procedure is not extremely invasive or very painful and can usually be tolerated awake. Most procedures that CAN be tolerated awake ARE done awake. ...
DoctorWhom's user avatar
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8 votes
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What is the difference between Eisenmenger syndrome and ventricular septal defect?

Ventricular septal defect A ventricular septal defect (VSD) is a congenital defect of the central wall (septum) of the heart. This septum divides the right ventricle of the heart from the left ...
Chris's user avatar
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7 votes

Pacemaker and MRI

Some new pacemakers are MRI compatible ([1]). Of those, some have an exclusion zone where the body may not be scanned. I wouldn't be surprised if, in a few years, all new pacemakers and ICDs will be ...
watkipet's user avatar
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7 votes
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Heart Attack Risk Score calculation

I think you are looking for the the risk score assessment tool based on the Framingham Heart Study. It predicts a person’s risk of having a heart attack in the next 10 years. It takes into account ...
S.Victor's user avatar
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7 votes
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Can Manual External Defibrillators "restart" a heart?

Your technical understanding is correct and television is fiction. In fact, watching shows involving CPR and defibrillation is a source of both amusement and frustration for most medical professionals ...
Carey Gregory's user avatar
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7 votes

What is the difference between Eisenmenger syndrome and ventricular septal defect?

Eisenmenger syndrome is a clinical syndrome. A ventricular septal defect (VSD) is an anatomic lesion. They are related in that Eisenmenger syndrome can be caused by a VSD (among other things). VSD A ...
De Novo's user avatar
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7 votes
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Are defibrillator leads actually clashed against each other?

While it used to be done, in reality anymore it isn't done as it is possible to damage the equipment by rubbing, and the possibility exists of an accidental discharge between paddles which can be ...
JohnP's user avatar
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7 votes

How does a prosthetic heart valve "burst"?

There are a number of different heart valve prostheses, and the age and type of the valve in question would make answering the question somewhat easier and more specific. Prosthetic heart valves are ...
Gerry Creager's user avatar
6 votes

Are there a maximum number of times for surgical ablations on patients with Atrial Fibrillation?

In 2013, a systematic review and meta-analysis (see ref in source) examined the long term outcome of catheter ablation in patient with atrial fibrillation. They first looked at single procedure ...
M. Arrowsmith's user avatar
6 votes
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What does "sinus rhythm otherwise normal ECG" mean?

Basically you have a normal ECG reading according to the machine. Sinus rhythm (as explained in the first section of this book chapter) is normal, meaning that the heart is depolarized by a wave ...
JohnP's user avatar
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6 votes
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What does "Townsend quintile" mean?

The "Townsend deprivation score" measures socio-economic status, and has five categories, hence you are being asked for your quintile. The scale is 1-5, and it incorporates the variables car ...
YviDe's user avatar
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6 votes
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Why do we continue compressions after the first AED shock?

The only thing that keeps a patient in cardiac arrest alive is constant, high-quality chest compression. Cardioversion ("shocking") of a patient aims to return the heart to normal (sinus) rhythm in ...
JWC's user avatar
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6 votes
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Does COVID-19 cause myocardial infarctions?

Cardiovascular disease is known to worsen during infections such as influenza through two proposed mechanisms: cytokines from the resulting inflammation cause weaken atherosclerotic plaques and cause ...
D.Tan's user avatar
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5 votes

What does "sinus rhythm otherwise normal ECG" mean?

Basically I agree with JohnP. The "otherwise normal ecg" is an unfortunate phrase. Sinus rhythm is the normal rhythm of the heart. So the machine should interpret as: Normal ECG. Rhythm:Sinus Heart ...
Prodromos Regalides's user avatar
5 votes
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Blood pressure in aorta vs. blood pressure in brachial artery

The mean pressure has to be lower peripherally for blood to flow in that direction. However, it is well known that there is an amplification of systolic blood pressure in the limbs due to reflection ...
rncardio's user avatar
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5 votes

How can blood pressure be high but my pulse low?

If that is the accurate pressure, you really need to go to the emergency room! 188 is high but not immediately dangerous, but 134 for a diastolic is outrageous. At very least go to an urgent care or ...
quietmedic's user avatar
5 votes
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Mechanical cardio resuscitation for asystole

"Giving" electrical current to the heart does not necessarily translate to mechanical contractions. The excitation-contraction coupling (as the sequence of electrical activation an muscle contraction ...
Prodromos Regalides's user avatar
5 votes

Does the digestive disorders affect the location of aorta beat around navel?

During my last course called "Physical Examination of the Abdomen" (at medical school), we learned to palpate the abdominal aorta, which can be easily palpated in +/- lean patients. This ...
Felipe's user avatar
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5 votes
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adequate exposure of the surgical field

It simply means visually exposing the tissues the surgeon needs to operate on. For example, if the surgeon needs to cut or suture inside one of the chambers and it's full of blood, they would be ...
Carey Gregory's user avatar
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5 votes
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What's the difference between a fast heart rate during exercise, and a fast heart rate during an anxiety attack?

It is not a fast heart rate but the underlying mechanisms that can affect health. The mechanisms involved in exercise can be beneficial and those in anxiety harmful. EXERCISE Physiological responses ...
Jan's user avatar
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5 votes
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Why is the crescendo-decrescendo systolic murmur best heard at the cardiac base?

It's not, unless you are using the term "base" to refer to the aortic root of the heart rather than the apex. A systolic "crescendo-decrescendo murmur" is the classic description for the murmur ...
DoctorWhom's user avatar
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5 votes
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Ventricular diastolic pressure?

First, I’ll cover some anatomy and physiology of the heart. Cardiac anatomy The heart is divided into two sides. The right side (on the left of the image) receives blood from the body and pumps it ...
Chris's user avatar
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4 votes
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Can weak people use their feet when doing CPR?

Mechanically, if you have good enough foot control to be able to meet compressions guidelines, then a compression is a compression. But there are a few things to consider. Most importantly, what a ...
DoctorWhom's user avatar
  • 5,774
4 votes

Why do we continue compressions after the first AED shock?

There are several studies that emphasize the importance of providing rapid and deep compressions and that CPR should resume immediately after the shock given by the AED, without the delay entailed in ...
Floyd Mitchell's user avatar
4 votes

What is the difference between Eisenmenger syndrome and ventricular septal defect?

Apart from information on differences given in two excellent answers here, there is a major difference in treatment of these two conditions. Ventricular Septal Defect (VSD) before development of ...
rncardio's user avatar
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4 votes
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Difference between acyanotic and cyanotic

Cyanosis refers to a blue discolouration of the skin caused by hypoxia (inadequate oxygenation of the arterial blood supply). It is the presence or absence of this hypoxia that is actually the ...
Chris's user avatar
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