Archive for March 2011
An emergency medical technician (EMT) can come into contact with hazardous materials very easily if he is not aware of his surroundings. A hazardous material is any substance that poses a threat or unreasonable risk to a person’s life, health, or property if it is not manufactured, packaged, processed, handled, stored, transported, used or disposed of properly. Because there are many different types of potentially hazardous materials, if an EMT suspects that a hazardous material is present at a scene he or she should notify his crew immediately and take precautions to keep him and others away from danger.
Hazardous materials incidents should always be handles by people who are trained for that specific type of material. Generally, specialty equipment and knowledge about the dangers of hazardous materials are needed. An EMT should allow the hazardous materials team to handle all hazardous materials.
If hazardous materials are suspected at a scene then stay away from the materials. Binoculars are helpful tools for identifying hazardous goods from a safe distance. They can be used to identify any placard or markings that may be on or close to the hazardous material without having to get too close to it. Motor vehicles that carry hazardous materials are required to have a placard displayed that identifies that type of material that is transported by that vehicle.
Protective clothing should be used when dealing with hazardous materials. There are different levels of hazardous materials suits and self-contained breathing apparatuses that may be required for protection. The protective equipment should always be worn when in close contact with hazardous materials.
EMT’s should provide emergency care to patients only after the scene is safe. If emergency care can be provided away from a contaminated scene then every effort should be made to relocate patients to a safe location. It is not safe to enter a scene to remove a contaminated patient until the patient has been decontaminated. Any premature entry into a hazardous area can pose a serious health risk to the patient, bystanders and EMT.
Blood flows through a network of arteries, veins and capillaries that form a pathway through the body. This pathway allows for the delivery of nutrients and oxygen to all of the cells and also allows for the removal carbon dioxide and waste products that are the result of metabolism. Blood flow is important knowledge for any allied health degree.
There are three types of arteries that help to transport blood to the cells of the body. Elastic arteries are thick walled arteries that are found near to the heart. They are also the largest in diameter and, as their name suggests, the most elastic. Elastic arteries have large lumens which makes them low-resistance pathways for blood from the heart to smaller, medium sized arteries.
Muscular, or disturbuting arteries, deliver blood to specific body organs. The internal diameter of a muscular artery ranges form 1 cm to 0.3 mm. These arteries have thick tunica media and more smooth muscle than elastic arteries. They are also less elastic.
Arterioles are the smallest arteries in the body. These small arteries are made up mostly of smooth muscle with a few elastic fibers. The diameter of arterioles affects the blood flow into capillary beds. The diameter is varies based on neural, hormonal and local chemical influences or changes. When arterioles constrict, the tissues that are usually fed blood are bypassed. When arterioles dilate, the amount of blood that flows into the capillaries along the pathway increases greatly.
The smallest blood vessels of the body are microscopic capillaries. With very small thin walls made of smooth-muscle like cells, capillaries provide direct access to almost every cell in the body. These small vessels have exchange gases, nutrients, hormones and other materials between blood and interstitial fluid.
There are three types of capillaries that can be found in the body. Continuous, fenestrated, and sinusoidal capillaries help to exchange gases, nutrients, hormones and other materials between blood and interstitial fluid.
Continuous capillaries are especially abundant in the skin and muscles. These types of capillaries have endothelial cells that provide an uninterrupted lining. Adjacent cells are joined laterally to capillaries by tight junctions. These junctions have gaps that allow the limited passage of fluids and small solutes.
Fenestrated capillaries are a lot like continuous capillaries, except that some of the endothelial cells in fenestrated capillaries have pores that make them more permeable to fluids and small solutes. These types of capillaries are found where ever active capillary absorption or filtrate formation occurs, such as the small intestine where nutrients are digested and absorbed, also the endocrine organs, which allow hormones rapid entry into the blood. These types of capillaries are also located in the kidneys with open pores that allow for the rapid filtrations of blood plasma.
Sinusoidal capillaries are found only in the liver, bone marrow, spleen and adrenal medulla. These types of capillaries highly modified with large irregularly shaped lumens that are usually full of fenestrated pores. The endothelium of the sinusoidal capillary has fewer tight junctions, making them especially leaky and able to allow large molecules to pass between the blood and tissues. The liver contains sinusoidal capillaries with large hepatic macrophages are able to remove and destroy any bacteria that comes into contact with the endothelium.
The heart is a ceaseless muscle that pumps blood with efficiency to meet the needs of the tissues of the body. In normal healthy people, the heart’s continuous pumping action maintains a delicate balance between cardiac output and venous return. This balance is necessary otherwise a dangerous back up of blood can occur in the veins responsible for returning blood to the heart. When studying how to become an allied health professional such as an EMT, Paramedic or even how to become a phlebotomist, it pays to be wise about the heart.
Cardiac output is the amount of blood that is pumped out of each ventricle of the heart in 1 minute. When this output is so low that blood circulation is not able to meet the needs of tissues throughout the body, the heart is said to be in congestive heart failure. This heart condition can progress and worsen as the myocardium continues to weaken. There are several conditions that can cause the myocardium to become weak an unable to contract.
Coronary artherosclerosis is a condition that the coronary vessels to clog with fatty buildup. This can impair blood and oxygen from being delivered to the cardiac cells causing the heart to become hypoxic and eventually unable to contract effectively.
Persistent high blood pressure can also cause the heart to become weak. In normal healthy hearts, pressure in the aorta during diastole is 80 mm Hg. When the aortic blood pressure rises to 90 mm Hg or higher, the myocardium must use more force to open the aortic valve in order to pump out the same amount of blood. A chronic condition of high blood pressure can cause the myocardium to hypertophy and with time become weaker and weaker.
A myocardial infraction is commonly called a heart attack and is usually the result of prolonged coronary blockage. Multiple myocardial infractions can slow down the pumping efficiency of the heart. This occurs because heart attacks cause the heart cells to not able to receive blood due to a coronary blockage, which results in dead heart cells that are eventually replaced with noncontractile scar tissue.
Breathing is most easily assessed by observing a patient’s chest rise and fall. To assess a patient accurately the rate and quality of breath should be observed.
A patient’s respiratory rate can be determined by counting the number of breaths that are taken in 30 seconds. The number of breaths observed during that amount of time is multiplied by two. To obtain a more accurate rate, count the number of breaths for 1 full minute. This is especially for helpful for obtaining a more accurate assessment if the patient’s breathing is irregular. It is best not to inform the patient that you will be doing a breathing assessment. Often patients change their breathing when they are told that someone will be observing them. The best way to avoid having to tell the patient that you are performing an assessment is to count respirations right after the pulse is assessed. This can be done by keeping your hand in contact with the patient’s wrist after the pulse is assessed.
A patient’s respiratory rate can be affected by several conditions. The patient’s age, size and emotional state can all affect respiratory rate. A patient that is ill or injured may breath faster than usual. Adults’ average 12 to 20 breathes per minute.
The quality of breathing is part of a thorough breathing assessment. There are four categories to this assessment. These categories will classify the breathing as being either normal, shallow, labored and noisy.
Normal breaths are observed with the chest moves outward and downward in a smooth manner. The rhythm for normal breathing should be even and effortless. If breathing is difficult accessory muscles in the abdomen, shoulder, and neck are often used.
Labored breathing is usually indicated by the amount of effort the patient must exert to breath. Often the patient will make grunting or stridor noises when the breathing is labored. Grunting noises are created when the patient exhales against a closed glotiic opening. Stridor is a loud high-pitched sound that is often heard during inspiration with labored breathing.
Noisy breathing is usually the result of an obstruction. Snoring, wheezing, gurgling, and crowing are examples of noisy respirations.
Spinal injuries are can result from an accident if a significant amount of force was applied to the patient’s body during the incident. In most situations, an emergency medical technician (EMT) can determine if the mechanism of injury involved is significant enough to suspect that the patient may have a spinal injury that will require immobilization.
There are several possible significant mechanisms of injury that can cause an EMT to assume possible spinal injury. They are:
-Motor vehicle crash
-Pedestrian injured in vehicle collision
-Fall from a significant height
-Blunt trauma to the head, chest, abdomen or pelvis
-Penetrating trauma to the head, neck or torso
-Motorcycle crash
-Hanging
-Diving accident
-Any trauma resulting in unresponsive patient
When an EMT first arrives on scene, he or she will make an initial assessment of the scene. Serious injuries or life-threatening conditions will be treated first. There are specific signs and symptoms that lead the EMT to suspect a possible head or spinal injury.
An EMT should evaluate the patient. A patient with spinal injuries may feel tenderness around an injured area. There may also be pain if the neck is moved. It is important that an EMT never ask the patient to move his or her spine to determine if pain exists. The patient may feel pain that is not associated with movement or palpitation along the spine or the extremities. The patient should be asked to remain still and not move while the EMT asks questions about where their pain is located.
An EMT is likely palpitate soft tissue areas in search of obvious deformity along the spine at a possible injured area. The head and neck may show injury along with the cervical spine. If there is shoulder, back or abdominal injury it is possible that the patient has a thoracic or lumbar spine injury.
A patient with spinal injuries can very easily suffer from complications such as inadequate breathing and paralysis. An emergency medical technician should immobilize the patient to prevent excessive movement. In-line cervical spinal immobilization can be accomplished when a patient is in a seated or lying down position. To do this, the EMT, should place both hands on the corner of the patient’s jaw on both sides. If the patient is sitting down the EMT should stand behind the patient and grasp the corner of the patient’s jaw on both sides. The EMT will then grasp the corner of the jaw and stabilize the neck by wrapping your hands around the posterior portion of the neck. This should put the patient’s head in a neutral position in alignment with the spine. This position should not be attempted if the patient complains of pain or if the head does not easily move into position.
The patient’s vital signs and motor and sensory functions should be reassessed after the patient has been immobilized. Reassessment is important because any movement could cause paralysis. A patient that is combative or uncooperative should also be reassessed after any significant movement to ensure that the patient has not incurred additional injury.
A spinal cord injury can make breathing difficult. This is commonly seen with cervical or thoracic injuries. A bag-valve mask can be used to assist a patient who has difficulty breathing. Any patient that has difficulty breathing should be watched closely.
If a patient vomits while immobilized there is a good possibility that the airway may be obstructed. Suction should be used to clear the airway. If the patient is immobilized on a long backboard the airway can be cleared by tilting them to the side.
Elderly patients are usually more likely to have cardiovascular problems because of the gradual narrowing of the arteries over several years. Because of the progressive narrowing, several conditions that are not considered serious in younger patients may represent serious diseases in elderly patients. A prime example of this can be seen with a condition called syncope. This condition causes fainting due to a decrease in blood flow to the brain. Patients over the age of 60 have an increased chance of dying from this condition.
Elderly patients may have signs or symptoms associated with myocardial infarction (MI). The classic symptoms associated with this condition are chest pains, sweating and pain or numbness in the left arm or jaw. These symptoms are not always present in elderly patients. Atypical presenting symptoms of MI include syncope, difficulty breathing, abdominal or epigastric pain, or fatigue. Close to half of the elderly patients who have acute MI have shortness of breathe and usually do not have chest pains.
Many elderly patients also have a condition called angina where the heart muscle does not receive adequate amounts of blood. A stable form of this condition allows the heart to receive enough blood at rest. However, if a person with this condition exerts too much effort, blood flow to the vessels becomes insufficient and chest pains or shortness of breath can result. These symptoms are often relieved with rest. Nitroglycerin is commonly used to treat angina. Nitroglycerin is absorbed from under the tongue. This medication is effective at improving coronary artery blood flow and relieving the symptoms associated with angina.
