Tailored anti-platelet therapy, made possible through a novel point-of-care genetic test, optimizes treatment for patients who carry a common genetic variant, researchers at the University of Ottawa Heart Institute (UOHI) have found.

09 Nov 2011

A UOHI clinical trial known as RAPID GENE studied 200 patients undergoing coronary stent implantation for acute coronary syndrome or stable angina. Use of a simple, saliva swab test performed by nurses at the bedside on half of the patients allowed doctors to almost instantly identify those with the genetic variant, known as CYP2C19*2, which puts them at risk of reacting poorly to standard anti-platelet drug therapy, and administer an alternative drug.

The study demonstrated that tailored drug treatment therapy made possible by the genetic testing successfully protected all of the patients with the at-risk genetic variant from subsequent adverse events, while 30 per cent of patients treated with standard therapy did not receive adequate protection.

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The following article is validation to why every paramedic should continually talk to unresponsive patients.

Study using EEG opens new opportunities for communicating, researchers say

The Canadian Press Posted: Nov 9, 2011 8:16 PM ET Last Updated: Nov 10, 2011 5:27 PM ET

Dr. Damian Cruse checks volunteer Irene Sperandio at the University of Western Ontario London, Ont. University of Western Ontario/Canadian Press

Researchers have discovered they can detect conscious awareness in some patients thought to be in a permanent vegetative state using an inexpensive EEG device that measures electrical activity in the brain.

The use of an electroencephalography, or EEG, machine, which can easily be transported to a patient’s bedside, follows an earlier breakthrough employing a functional MRI scanner to determine whether some people in a vegetative state were in fact consciously aware but unable to physically respond to stimuli.

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Hypertension aka High Blood Pressure

Blood pressure is defined as the pressure exerted by the blood against the artery walls.

Hypertension is one of the risk factors that has been correlated to and causative of many other human diseases.

Normal blood pressure is ~120/80 mmHg, hypertension in stage 1 is 140-159/90-99 and hypertension in stage 2 is 160+/100+.

Changes that Occur in Blood Pressure

Blood pressure can be determined by a formula:
Blood Pressure = Cardiac Output x Peripheral Resistance

In general terms blood pressure here is defined as the amount of blood exiting the heart and the amount of resistance it receives travelling through the body.

Cardiac Output = stroke volume x heart rate. The stroke volume is the amount of blood that leaves the left ventricle in one beat and heart rate is the amount of beats per minute. This gives you the amount of blood leaving the heart in one minute.

Peripheral Resistance is the amount of resistance the blood meets when travelling through the body. There are 3 categories of resistance: 1) blood vessel diameter, 2) blood viscosity, and 3) blood vessel length.

1) Blood Vessel Diameter: Since the blood is being pushed all at once through the blood vessels the room it has to move in impacts the resistance it meets (as well as the elasticity or ability of the vessels to stretch). When the vessel is larger then more blood passes through at once, this leaves a lower blood pressure, but when the vessel is too small to accommodate the blood then the pressure on the vessel rises.
The size of the vessel can be changed by the nervous system, hormones, chemicals and acid-base imbalances by controlling the smooth muscle tissue within the arteries/arterioles, and sphincters which control blood flow.

2) Blood Viscosity: Viscosity is simply the thickness of the fluid (blood). When the blood is thicker it is harder for particles (like plasma proteins) to flow past each other within the given vessel diameter. Therefore when the blood is thicker the pressure on the vessel is higher.

3) Blood Vessel Length: The longer a route is for the blood the pass through the body the more resistance the blood meets along the way, this causes an increased blood pressure. Fat and cancer cells create and require more blood vessels in order to function appropriately, these will increase the blood pressure since the path back to the heart is longer.

Measuring Blood Pressure

Blood pressure is measured with a sphygmomanometer (cuff that goes around the arm with a pressure gauge and pump) when the pressure on the arm is released the user must listen with a stethoscope to hear the rhythmic heart beat. The first normal beat you hear is the systolic pressure and the last normal beat you hear is the diastolic pressure.

If you don’t have any equipment available here is a tip to know a guideline of blood pressures in adults:
Carotid pulse: systolic of ~40mmHg.
Brachial pulse: systolic of ~60mmHg.
Radial pulse: systolic of >80mmHg.
Femoral pulse: systolic of ~80mmHg.

Causes of Hypertension

Some of the risk factors for hypertension include: heredity, age, race, insulin resistance, metabolic abnormalities, high salt intake, obesity, excessive alcohol consumption and low potassium dietary intake.

Heredity: Statistics show that there is a hereditary link in hypertension but research has shown that hypertension is not caused by one specific gene but many.

Age: Hypertension increases with age, and may appear later in life in patients that previously had normal blood pressure.

Race: Statistics show that African Americans have a higher prevalence of hypertension and earlier onset.

Insulin resistance: means that there is a higher amount of glucose (sugar) in the blood which causes the viscosity to increase resulting in hypertension.

High salt intake: There is a common saying that water flows where the sodium goes, if there is a high amount of sodium-salt in the diet then more water will be retained in the blood (increased viscosity) which leads to hypertension.

Obesity: causes insulin resistance (viscosity again) and a possible increase in aldosterone production, as well as increased adipose (fat) tissue which requires more capillaries (increase vessel length).

Excessive alcohol intake: effects blood pressure when it is 3 or more drinks daily, but the cause is unknown.

Potassium levels: have only been correlated with sodium intake (generally people that consume more potassium consume less sodium). Therefore, low potassium means more sodium, which means more water and greater viscosity.

As you can see from the above, some factors can be eliminated through lifestyle choices and others cannot.

Organ Damage

Hypertension causes/leads to the following organ damage:
a) Heart: left ventricular hypertrophy, angina or prior myocardial infarction, prior coronary revascularization, heart failure.
b) Brain: stroke or TIA
c) Chronic kidney disease
d) Peripheral vascular disease
e) Retinopathy

Recommended Read

A research paper detailing the increasing incidence of hypertension in Canada.
http://www.cmaj.ca/content/178/11/1429.full.pdf+html

Sources

1. Porth, Carol, Glenn Matfin, and Carol Porth. Pathophysiology: Concepts of Altered Health States. Philadelphia, PA: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2009. Print.

2. National Heart, Lung and Blood Institute. (2003). The seventh report of the National Committee on Detection, Evaluation, and Treatment of High Blood Pressure. Publication no. 03-5233. Bethesda, MD: National Institutes of Health.

With New Discovery by Weill Cornell Medical College Researchers

STUDY’S AUTHORS SHOW BLOOD VESSELS SUPPORT LUNG REGENERATION AND THEIR FINDINGS COULD POTENTIALLY OPEN THE DOOR TO THERAPY FOR LUNG DISORDERS

NEW YORK (Oct. 28, 2011) — Researchers at Weill Cornell Medical College say they have taken an important step forward in their quest to “turn on” lung regeneration — an advance that could effectively treat millions of people suffering from respiratory disorders.

In the Oct. 28 issue of the journal Cell, the research team reports that they have uncovered the biochemical signals in mice that trigger generation of new lung alveoli, the numerous, tiny, grape-like sacs within the lung where oxygen exchange takes place. Specifically, the regenerative signals originate from the specialized endothelial cells that line the interior of blood vessels in the lung.

Read More from Cornell Medical College

The Canadian C-Spine Rule was created in response to increased costs associated with non-essential radiography (98%) and increased patient wait times while immobilized to back boards. This month’s article will review the research and findings associated with the Canadian C-Spine Rule (CCR) and relate them to EMS practices.

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