Project Chitra Hospital Training FINAL (1)

7/28/2019 Project Chitra Hospital Training FINAL (1)

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VEL TECH MULTI TECH

Dr.RANGARAJAN Dr.SAKUNTHALAENGINEERING COLLEGE

(Approved by AICTE, New Delhi & Affiliated to Anna University, Chennai)

No.60, Avadi Vel Tech Road, Chennai 600 062.

BM2356- HOSPITAL TRAINING LAB

NAME : M.CHITRA

ROLL NO. : VM4813

REGISTER NO : 11809121004

BRANCH : BIOMEDICAL ENGINEERING

YEAR : IV year


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VEL TECH MULTI TECHDr.RANGARAJAN Dr.SAKUNTHALA

ENGINEERING COLLEGE(Approved by AICTE, New Delhi & Affiliated to Anna University, Chennai)

No.60,Avadi Vel Tech Road, Chennai 600 062.

Name M.CHITRA

Year IV Semester VII Branch BIOMEDICAL

ENGINEERING University Register No11809121004 College Roll No VM4813

Certified that this is the bonafide record of work done by the above student in

the Hospital Training Lab (BM2405) during the academic year 2012-2013

.. ..

Signature of HOD Signature of Lab Incharge

________________________________________________________________

Submitted for the University Practical Exam held on atVELTECH MULTI TECH Dr.RANGARAJAN Dr.SAKUNTHALA ENGINEERING

COLLEGE,#60,AVADI VEL TECH ROAD,CHENNAI 62.

Signature of ExaminersInternal: . External: .

Date:


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HOSPITALTRAININGVenue : Rohini Multi Speciality Hospital,

Near Manimandapam,Tanjore,

Thanjavur-613007

Date of visit :13th August 2012 to 17th August 2012.


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Departments in hospital

Intensive care unit(ICU)

Dialysis center

Computed Tomography(CT)

Magnetic Resonance Imaging(MRI)

X-Ray

Echocardiogram and TMT

Electromyography (EMG)

Electroencephalogram(EEG)

Electrocardiogram(ECG)

Ultrasonography
http://www.google.co.in/url?sa=t&rct=j&q=electrocardiogram&source=web&cd=3&cad=rja&ved=0CD4QFjAC&url=http%3A%2F%2Fwww.nobelprize.org%2Feducational%2Fmedicine%2Fecg%2F&ei=VFlDUJ7yG8jYrQfNioDICA&usg=AFQjCNH7CTgx7XsIlyduQkxCBLX8bfoQ9Ahttp://www.google.co.in/url?sa=t&rct=j&q=electrocardiogram&source=web&cd=3&cad=rja&ved=0CD4QFjAC&url=http%3A%2F%2Fwww.nobelprize.org%2Feducational%2Fmedicine%2Fecg%2F&ei=VFlDUJ7yG8jYrQfNioDICA&usg=AFQjCNH7CTgx7XsIlyduQkxCBLX8bfoQ9A


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ROHINI MULTI SPECIALITY HOSPITAL,

THANJAVUR

HISTORY :

Rohini multi speciality hospital is located in thanjavur .Rohini hospital are among

the topnotch hospitals in Thanjavur ISO 9001 : 2000 Certified Hospital . They are

known to provide medical and therapeutic services. In the year 2006-07, about 5864

major and 3747 minor surgeries took place in Rohini multi speciality

hospital,thanjavur.. Trauma cases account for 90 percent of the inpatient admission

daily in the hospital.

It is located in thanjavur near Manimandapam which is one of the famous tourist

spot. The Managing Director of Rohini hospital is Dr.R.Rathina Sabapathy

M.s.,Orth,DOrth.Cons.Ortho Surgen .

Constructed at a cost of Rs. 38 crore, the buildings include a 300-bed hospital,

provisions for the functioning of all specialty departments, out-patient ward,

laboratory buildings, etc. Hospital super-specialty departments are Neuro Surgery,

Neurology, Urology, Nephrology, Medical Gastroenterology, Surgical

Gastroenterology, Thoracic Medicine, Oto-Rhino-Laryngology (ENT), Cardiology,

gynaecology , paediatrics, Cardio Thoracic Medicine, casualty block, laboratories

and all outpatient wards.


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1. INTENSIVE CARE UNIT(ICU)

Intensive care unit (ICU) equipment includes patient monitoring, respiratory and

cardiac support, pain management , emergency resuscitation devices, and other

life support equipment designed to care for patients who are seriously injured, have

a critical or life-threatening illness, or have undergone a major surgical procedure,

thereby requiring 24-hour care and monitoring.

PURPOSE :

An ICU may be designed and equipped to provide care to patients with a range ofconditions, or it may be designed and equipped to provide specialized care to

patients with specific conditions. For example, a neuromedical ICU cares for

patients with acute conditions involving the nervous system or patients who have

just had neurosurgical procedures and require equipment for monitoring and

assessing the brain and spinal cord. A neonatal ICU is designed and equipped to

care for infants who are ill, born prematurely, or have a condition requiring constant

monitoring. A trauma/burn ICU provides specialized injury and wound care for

patients involved in auto accidents and patients who have gunshot injuries or burns.
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DESCRIPTION:

Intensive care unit equipment includes patient monitoring, life support and

emergency resuscitation devices, and diagnostic devices.

Patient monitoring equipment :

Patient monitoring equipment includes the following:

Multiparameter monitoring systemcomprehensive patient monitoring systems

that can be configured to continuously measure and display a number of parameters

via electrodes and sensors that are connected to the patient. These may include the

electrical activity of the heart via an EKG, respiration rate (breathing), blood

pressure, body temperature, cardiac output, and amount of oxygen and carbondioxide in the blood. Each patient bed in an ICU has a multiparameter monitor that

measure these body activities. All monitors are networked to a central nurses'

station. These lightweight parameter patient monitors and compact multiparameter

patient monitor are used to monitor different body conditions of patients like heart

beat, ECG, pulse oxygen saturation, noninvasive blood pressure and respiration.

Further, these portable patient monitor are capable of working on both alterative

current as well as direct current.

Pulse oximetermonitors the arterial hemoglobin oxygen saturation

(oxygen level) of the patient's blood with a sensor clipped over the finger or

toe


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LIFE SUPPORT AND EMERGENCY RESUSCITATIVE

EQUIPMENT :

Intensive care equipment for life support and emergency resuscitation includes the

following:Ventilator (also called a respirator)assists with or controls pulmonary

ventilation in patients who cannot breathe on their own. Ventilators consist of a

flexible breathing circuit, gas supply, heating/humidification mechanism, monitors,

and alarms. They are microprocessor-controlled and programmable, and regulate

the volume, pressure, and flow of patient respiration. Ventilator monitors and

alarms may interface with a central monitoring system or information system.

Infusion pumpdevice that delivers fluids intravenously or epidurally

through a catheter. Infusion pumps employ automatic, programmable

pumping mechanisms to deliver continuous anesthesia, drugs, and blood

infusions to the patient. The pump is hung on an intravenous pole placed next

to the patient's bed.


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DefibrillatorA defibrillator is a machine used to shock the victim's heart

and restore the heart's normal rythmic patterns. When a defibrillator is used,

it in effect kicks the heart into action again, causing it to resume sending

blood throughout the body.

DIAGNOSTIC EQUIPMENT:

The use of diagnostic equipment is also required in the ICU. Mobile x-ray units are

used for bedside radiography, particularly of the chest. Mobile x-ray units use a

battery-operated generator that powers an x-ray tube. Handheld, portable clinical

laboratory devices, or point-of-care.

Analyzers, are used for blood analysis at the bedside. A small amount of whole

blood is required, and blood chemistry parameters can be provided much faster than

if samples were sent to the central laboratory.


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OTHER ICU EQUIPMENT:

GlucometerA glucose meter (or glucometer) is a medical device for

determining the approximate concentration ofglucose in theblood. It is a key

element of homeblood glucose monitoring (HBGM) by people with diabetesmellitus orhypoglycemia. A small drop of blood, obtained by pricking the

skin with a lancet, is placed on a disposable test strip that the meter reads and

uses to calculate the blood glucose level. The meter then displays the level in

mg/dl or mmol/l.

LaryngoscopyLaryngoscopy (larynx + scopy) is a medical procedure that

is used to obtain a view of the vocal folds and the glottis. Laryngoscopy maybe performed to facilitate tracheal intubation during general anesthesia or

cardiopulmonary resuscitation or for procedures on the larynx or other parts

of the uppertracheobronchial tree.

Arterial Blood Gas(ABG) An arterial blood gas (ABG) is ablood test that

is performed usingblood from an artery. It involves puncturing an artery with

a thin needle and syringe and drawing a small volume of blood. The most

common puncture site is the radial artery at the wrist, but sometimes the

femoral artery in the groin or other sites are used. The blood can also be

drawn from an arterial catheter
http://en.wikipedia.org/wiki/Medical_devicehttp://en.wikipedia.org/wiki/Glucosehttp://en.wikipedia.org/wiki/Bloodhttp://en.wikipedia.org/wiki/Blood_glucose_monitoringhttp://en.wikipedia.org/wiki/Diabetes_mellitushttp://en.wikipedia.org/wiki/Diabetes_mellitushttp://en.wikipedia.org/wiki/Hypoglycemiahttp://en.wikipedia.org/wiki/Blood_lancethttp://en.wikipedia.org/wiki/Larynxhttp://en.wikipedia.org/wiki/Scopehttp://en.wikipedia.org/wiki/Vocal_foldshttp://en.wikipedia.org/wiki/Glottishttp://en.wikipedia.org/wiki/Tracheal_intubationhttp://en.wikipedia.org/wiki/General_anesthesiahttp://en.wikipedia.org/wiki/Cardiopulmonary_resuscitationhttp://en.wikipedia.org/wiki/Larynxhttp://en.wikipedia.org/wiki/Tracheobronchial_treehttp://en.wikipedia.org/wiki/Blood_testhttp://en.wikipedia.org/wiki/Bloodhttp://en.wikipedia.org/wiki/Arteryhttp://en.wikipedia.org/wiki/Radial_arteryhttp://en.wikipedia.org/wiki/Wristhttp://en.wikipedia.org/wiki/Femoral_arteryhttp://en.wikipedia.org/wiki/Groinhttp://en.wikipedia.org/wiki/Arterial_catheterhttp://en.wikipedia.org/wiki/Medical_devicehttp://en.wikipedia.org/wiki/Glucosehttp://en.wikipedia.org/wiki/Bloodhttp://en.wikipedia.org/wiki/Blood_glucose_monitoringhttp://en.wikipedia.org/wiki/Diabetes_mellitushttp://en.wikipedia.org/wiki/Diabetes_mellitushttp://en.wikipedia.org/wiki/Hypoglycemiahttp://en.wikipedia.org/wiki/Blood_lancethttp://en.wikipedia.org/wiki/Larynxhttp://en.wikipedia.org/wiki/Scopehttp://en.wikipedia.org/wiki/Vocal_foldshttp://en.wikipedia.org/wiki/Glottishttp://en.wikipedia.org/wiki/Tracheal_intubationhttp://en.wikipedia.org/wiki/General_anesthesiahttp://en.wikipedia.org/wiki/Cardiopulmonary_resuscitationhttp://en.wikipedia.org/wiki/Larynxhttp://en.wikipedia.org/wiki/Tracheobronchial_treehttp://en.wikipedia.org/wiki/Blood_testhttp://en.wikipedia.org/wiki/Bloodhttp://en.wikipedia.org/wiki/Arteryhttp://en.wikipedia.org/wiki/Radial_arteryhttp://en.wikipedia.org/wiki/Wristhttp://en.wikipedia.org/wiki/Femoral_arteryhttp://en.wikipedia.org/wiki/Groinhttp://en.wikipedia.org/wiki/Arterial_catheter


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Pulse oximetry plus transcutaneous carbon dioxide measurement is an alternative

method of obtaining similar information as well. An ABG is a test that measures the

arterial oxygen tension (PaO2), carbon dioxide tension (PaCO2), and acidity (pH). In

addition, arterial oxyhemoglobin saturation (SaO2) can be determined. Such

information is vital when caring for patients with critical illness or respiratory

disease. As a result, the ABG is one of the most common tests performed on

patients in intensive care units (ICUs).The test is used to determine thepH of the

blood, thepartial pressure ofcarbon dioxide and oxygen, and thebicarbonate level.

Many blood gas analyzers will also report concentrations oflactate, hemoglobin,

several electrolytes, oxyhemoglobin, carboxyhemoglobin and methemoglobin.

ABG testing is mainly used inpulmonology and critical care medicine to determine

gas exchange which reflect gas exchange across the alveolar-capillary membrane.

ABG testing also has a variety of applications in other areas of medicine.

Disposable ICU equipment includes urinary (Foley) catheters, catheters used for

arterial and central venous lines, Swan-Ganz catheters, chest and endotracheal

tubes, gastrointestinal and nasogastric feeding tubes, and monitoring electrodes.Some patients may be wearing a posey vest, also called a Houdini jacket for safety;

the purpose is to keep the patient stationary. Spenco boots are padded support

devices made of lamb's wool to position the feet and ankles of the patient. Support

hose may also be placed on the patient's legs to support the leg muscles and aid

circulation.
http://en.wikipedia.org/wiki/Pulse_oximetryhttp://en.wikipedia.org/w/index.php?title=Transcutaneous_carbon_dioxide_measurement&action=edit&redlink=1http://en.wikipedia.org/wiki/Arterial_oxygen_tensionhttp://en.wikipedia.org/wiki/Carbon_dioxide_tensionhttp://en.wikipedia.org/wiki/PHhttp://en.wikipedia.org/w/index.php?title=Arterial_oxyhemoglobin_saturation&action=edit&redlink=1http://en.wikipedia.org/wiki/PHhttp://en.wikipedia.org/wiki/Partial_pressurehttp://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Bicarbonatehttp://en.wikipedia.org/wiki/Lactic_acidhttp://en.wikipedia.org/wiki/Hemoglobinhttp://en.wikipedia.org/wiki/Electrolytehttp://en.wikipedia.org/wiki/Oxyhemoglobinhttp://en.wikipedia.org/wiki/Carboxyhemoglobinhttp://en.wikipedia.org/wiki/Methemoglobinhttp://en.wikipedia.org/wiki/Pulmonologyhttp://en.wikipedia.org/wiki/Gas_exchangehttp://en.wikipedia.org/wiki/Pulse_oximetryhttp://en.wikipedia.org/w/index.php?title=Transcutaneous_carbon_dioxide_measurement&action=edit&redlink=1http://en.wikipedia.org/wiki/Arterial_oxygen_tensionhttp://en.wikipedia.org/wiki/Carbon_dioxide_tensionhttp://en.wikipedia.org/wiki/PHhttp://en.wikipedia.org/w/index.php?title=Arterial_oxyhemoglobin_saturation&action=edit&redlink=1http://en.wikipedia.org/wiki/PHhttp://en.wikipedia.org/wiki/Partial_pressurehttp://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Bicarbonatehttp://en.wikipedia.org/wiki/Lactic_acidhttp://en.wikipedia.org/wiki/Hemoglobinhttp://en.wikipedia.org/wiki/Electrolytehttp://en.wikipedia.org/wiki/Oxyhemoglobinhttp://en.wikipedia.org/wiki/Carboxyhemoglobinhttp://en.wikipedia.org/wiki/Methemoglobinhttp://en.wikipedia.org/wiki/Pulmonologyhttp://en.wikipedia.org/wiki/Gas_exchange


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OPERATION :

The ICU is a demanding environment due to the critical condition of patients and

the variety of equipment necessary to support and monitor patients. Therefore,

when operating ICU equipment, staff should pay attention to the types of devicesand the variations between different models of the same type of device so they do

not make an error in operation or adjustment.

Although many hospitals make an effort to standardize equipmentfor example,

using the same manufacturer's infusion pumps or patient monitoring systems, older

devices and nonstandardized equipment may still be used, particularly when theICU is busy. Clinical staff should be sure to check all devices and settings to ensure

patient safety.

Intensive care unit patient monitoring systems are equipped with alarms that sound

when the patient's vital signs deterioratefor instance, when breathing stops, blood

pressure is too high or too low, or when heart rate is too fast or too slow. Usually,

all patient monitors connect to a central nurses' station for easy supervision. Staff at

the ICU should ensure that all alarms are functioning properly and that the centralstation is staffed at all times.

For reusable patient care equipment, clinical staff make certain to properly disinfect

and sterilize devices that have contact with patients. Disposable items, such as

catheters and needles, should be disposed of in a properly labeled container.

MAINTENANCE :

Since ICU equipment is used continuously on critically ill patients, it is essential

that equipment be properly maintained, particularly devices that are used for life

support and resuscitation. Staff in the ICU should perform daily checks on

equipment and inform biomedical engineering staff when equipment needs

maintenance, repair, or replacement. For mechanically complex devices, service

and preventive maintenance contracts are available from the manufacturer or third-

party servicing companies, and should be kept current at all times.


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HEALTH CARE TEAM ROLES:

Equipment in the ICU is used by a team specialized in their use. The team usually

comprises a critical care attending physician (also called an intensivist), critical care

nurses, an infectious disease team, critical care respiratory therapists,pharmacologists, physical therapists, and dietitians.

Physicians trained in other specialties, such as anesthesiology, cardiology,

radiology, surgery, neurology, pediatrics, and orthopedics, may be consulted and

called to the ICU to treat patients who require their expertise. Radiologic

technologists perform mobile x ray examinations (bedside radiography). Either

nurses or clinical laboratory personnel perform point-of-care blood analysis.

Equipment in the ICU is maintained and repaired by hospital biomedicalengineering staff and/or the equipment manufacturer.

Some studies have shown that patients in the ICU following high-risk surgery are at

least three times as likely to survive when cared for by "intensivists," physicians

trained in critical care medicine.


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2.DIALYSIS CENTER

In medicine, dialysis is primarily used to provide an artificial replacement for lost

kidney function (renal replacement therapy) due to renal failure. Dialysis may be

used for very sick patients who have suddenly but temporarily, lost their kidneyfunction (acute renal failure) or for quite stable patients who have permanently lost

their kidney function (stage 5 chronic kidney disease).

For patients with stage 5, or End-Stage Kidney Disease (ESKD), the decline in

kidney function occurred over a period of months to years until a level was reached

at which treatment was needed for survival. Unlike Acute Renal Failure (ARF)(Acute Kidney Injury (AKI)), Chronic Kidney Failure cannot be cured or reversed

and long-term treatments are needed to replace the lost functions of the kidney. The

treatment for ESKD that most naturally replaces lost kidney function is a kidney

transplant. However, some patients are not good candidates for a transplant due to

medical or other reasons, some cannot receive a transplant because of the short

supply of donor kidneys, and others simply decide that a transplant is not the best

option for them. As a result, most patients with ESKD must rely on dialysis to

replace the water and waste removal functions of the healthy kidneys.

The kidneys have important roles in maintaining health. When healthy, the kidneys

maintain the body's internal equilibrium of water and minerals (sodium, potassium,

chloride, calcium, phosphorus, magnesium, sulfate). Those acidic metabolism end

products that the body cannot get rid of via respiration are also excreted through the

kidneys. The kidneys also function as a part of the endocrine system producing

erythropoietin and 1,25-dihydroxycholecalciferol (calcitriol).
http://www.news-medical.net/health/Renal-Failure-What-is-Renal-Failure.aspxhttp://www.news-medical.net/health/Renal-Failure-What-is-Renal-Failure.aspxhttp://www.news-medical.net/health/Minerals-and-health.aspxhttp://www.news-medical.net/health/Calcium-What-is-Calcium.aspxhttp://www.news-medical.net/health/What-is-Metabolism.aspxhttp://www.news-medical.net/health/Renal-Failure-What-is-Renal-Failure.aspxhttp://www.news-medical.net/health/Renal-Failure-What-is-Renal-Failure.aspxhttp://www.news-medical.net/health/Minerals-and-health.aspxhttp://www.news-medical.net/health/Calcium-What-is-Calcium.aspxhttp://www.news-medical.net/health/What-is-Metabolism.aspx


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Erythropoietin is involved in the production of red blood cells and calcitriol plays a

role in bone formation. Dialysis is an imperfect treatment to replace kidney function

because it does not correct the endocrine functions of the kidney. Dialysis

treatments replace some of these functions through diffusion (waste removal) and

ultrafiltration (fluid removal).

DIALYSIS TYPES:

Dialysis works on the principles of the diffusion of solutes and ultrafiltration of

fluid across a semi-permeable membrane. Diffusion describes a property of

substances in water. Substances in water tend to move from an area where they are

in a high concentration to an area of low concentration. Blood flows by one side of

a semi-permeable membrane, and a dialysate, or special dialysis fluid, flows by theopposite side.

A semipermeable membrane is a thin layer of material that contains various sized

holes, or pores. Smaller solutes and fluid pass through the membrane, but the

membrane blocks the passage of larger substances (for example, red blood cells,

large proteins). The cleansed blood is then returned via the circuit back to the body.

Ultrafiltration occurs by increasing the hydrostatic pressure across the dialyzer

membrane. This usually is done by applying a negative pressure to the dialysatecompartment of the dialyzer. This pressure gradient causes water and dissolved

solutes to move from blood to dialysate, and allows the removal of several litres of

excess fluid during a typical 3 to 5 hour treatment.

In the US, hemodialysis treatments are typically given in a dialysis center three

times per week (due in the US to Medicare reimbursement rules); however, as of

2007 over 2,500 people in the US are dialyzing at home more frequently for various

treatment lengths. Studies have demonstrated the clinical benefits of dialyzing 5 to7 times a week, for 6 to 8 hours. These frequent long treatments are often done at

home, while sleeping but home dialysis is a flexible modality and schedules can be

changed day to day, week to week. In general, studies have shown that both

increased treatment length and frequency are clinically beneficial.
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PERITONEAL DIALYSIS:

In peritoneal dialysis, a sterile solution containing minerals and glucose is run

through a tube into the peritoneal cavity, the abdominal body cavity around the

intestine, where the peritoneal membrane acts as a semipermeable membrane.Theperitoneal membrane or peritoneum is a layer of tissue containing blood vessels that

lines and surrounds the peritoneal, or abdominal, cavity and the internal abdominal

organs (stomach, spleen, liver, and intestines). The dialysate is left there for a

period of time to absorb waste products, and then it is drained out through the tube

and discarded.

This cycle or "exchange" is normally repeated 4-5 times during the day, (sometimes

more often overnight with an automated system). Ultrafiltration occurs via osmosis;the dialysis solution used contains a high concentration of glucose, and the resulting

osmotic pressure causes fluid to move from the blood into the dialysate. As a result,

more fluid is drained than was instilled. Peritoneal dialysis is less efficient than

hemodialysis, but because it is carried out for a longer period of time the net effect

in terms of removal of waste products and of salt and water are similar to

hemodialysis. Peritoneal dialysis is carried out at home by the patient. Although

support is helpful, it is not essential. It does free patients from the routine of having

to go to a dialysis clinic on a fixed schedule multiple times per week, and it can be

done while travelling with a minimum of specialized equipment.
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HEMOFILTRATION:

Hemofiltration is a similar treatment to hemodialysis, but it makes use of a different

principle. The blood is pumped through a dialyzer or "hemofilter" as in dialysis, but

no dialysate is used.

A pressure gradient is applied; as a result, water moves across the very permeable

membrane rapidly, "dragging" along with it many dissolved substances, importantly

ones with large molecular weights, which are cleared less well by hemodialysis.

Salts and water lost from the blood during this process are replaced with a

"substitution fluid" that is infused into the extracorporeal circuit during the

treatment. Hemodiafiltration is a term used to describe several methods ofcombining hemodialysis and hemofiltration in one process.

INDICATIONS FOR DIALYSIS:

The decision to initiate dialysis or hemofiltration in patients with renal failure

depends on several factors. These can be divided into acute or chronic indications.

Indications for dialysis in the patient with acute kidney injury are: Metabolic acidosis in situations where correction with sodium

bicarbonate is impractical or may result in fluid overload.

Electrolyte abnormality, such as severe hyperkalemia, especially when

combined with AKI.
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Intoxication, that is, acute poisoning with a dialysable drug, such as

lithium, or aspirin.

Fluid overload not expected to respond to treatment with diuretics.

Complications of uremia, such as pericarditis, encephalopathy, or

gastrointestinal bleeding.

Chronic indications for dialysis:

Symptomatic renal failure

Low glomerular filtration rate (GFR) (RRT often

recommended to commence at a GFR of less than 10-15

mls/min/1.73m2). In diabetics dialysis is started earlier.

Difficulty in medically controlling fluid overload, serum

potassium, and/or serum phosphorus when the GFR is

very low.
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3.COMPUTED TOMOGRAPHY(CT)

A computed tomography (CT) scan uses X-rays to make detailed pictures of

structures inside of the body.

During the test, you will lie on a table that is attached to the CT scanner, which is a

large doughnut-shaped machine. The CT scanner sends X-rays through the body

area being studied. Each rotation of the scanner provides a picture of a thin slice of

the organ or area. All of the pictures are saved as a group on a computer. They also

can be printed.

In some cases, a dye called contrast material may be used. It may be put in a vein(IV) in your arm, or it may be placed into other parts of your body (such as the

rectum or a joint) to see those areas better. For some types of CT scans you drink

the dye. The dye makes structures and organs easier to see on the CT pictures.

A CT scan can be used to study all parts of your body, such as the chest, belly,

pelvis, or an arm or leg. It can take pictures of body organs, such as the liver,

pancreas, intestines, kidneys,bladder, adrenal glands, lungs, and heart. It also can

studyblood vessels, bones, and the spinal cord.

Fluoroscopy CT is a special test that is not widely available. It uses a steady beam

of X-rays to look at movement within the body. It allows the doctor to see your

organs move or to guide abiopsy needle or other instrument into the right place

inside your body.

SPIRAL CAT SCAN:

A conventional computerized axial tomography scan (CAT scan or CT scan) is an

x-ray procedure which combines many x-ray images with the aid of a computer to

generate cross-sectional views and, if needed, three-dimensional images of the

internal organs and structures of the body. A CAT scan is used to define normal and

abnormal structures in the body and/or assist in procedures by helping to accurately

guide the placement of instruments or treatments.
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A spiral CAT scan is a new specialized CAT scan technique that involves

continuous movement of the patient through the scanner with the ability to scan

faster and with higher definition of internal structures. Spiral CAT scanning can

permit greater visualization of blood vessels and internal tissues, such as those

within the chest cavity. This form of scanner may be particularly helpful in the

rapid evaluation of severe trauma injuries, such as those sustained in automobile

accidents.

A spiral CAT scan is also referred to as helical CAT scan.

WHY IT IS DONE:

CT scans are used to study areas of the body and the arms or legs.

Chest (thorax) A CT scan of the chest can look for problems with the

lungs, heart, esophagus, the major blood vessel (aorta), or the tissues in the

center of the chest. Some common chest problems a CT scan may find

include infection, lung cancer, apulmonary embolism, and an aneurysm.

AbdomenA CT scan of the abdomen can find cysts, abscesses, infection,

tumors, an aneurysm, enlarged lymph nodes, foreign objects, bleeding in the

belly, diverticulitis, inflammatory bowel disease, and appendicitis.
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Urinary tractA CT scan of the kidneys, ureters, and bladder is called a CT

KUB or CT urogram. This type of scan can find kidney stones, bladder

stones, or blockage of the urinary tract. See a picture of a CT of diseased

kidneys. A special type of CT scan, called a CT intravenous pyelogram

(IVP), uses injected dye (contrast material) to look forkidney stones,

blockage, growths, infection, or other diseases of the urinary tract.

LiverA CT scan can find liver tumors, bleeding from the liver, and liver

diseases. A CT scan of the liver can help determine the cause ofjaundice.

PancreasA CT scan can find a tumor in the pancreas or inflammation of

the pancreas (pancreatitis).

Gallbladder and bile ductsA CT scan can be used to check for blockageof thebile ducts. Gallstones occasionally show up on a CT scan. But other

tests, such as ultrasound, usually are used to find problems with the

gallbladder and bile ducts.

Adrenal glandsA CT scan can find tumors or enlarged adrenal glands.

SpleenA CT scan can be used to check for an injury to the spleen or the

size of the spleen.

PelvisA CT scan can look for problems of organs in the pelvis. For a

woman, these include the uterus, ovaries, and fallopian tubes. For a man, the

pelvic organs include theprostate gland and the seminal vesicles.

Arm or legA CT scan can look for problems of the arms or legs, including

the shoulder, elbow, wrist, hand, hip, knee, ankle, orfoot.
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OTHER USES FOR A CT SCAN:

A CT scan may be used to make sure a procedure is done correctly. For example,

the doctor may use CT to guide a needle during a tissue biopsy or to guide the

proper placement of a needle to drain an abscess.

For people with cancer, a CT scan can help determine how much the cancer has

spread. This is called staging the cancer.

HOW TO PREPARE:

Before the CT scan, tell your doctor if you:

Are or might be pregnant. Are allergic to any medicines, including iodine dyes.

Have a heart condition, such as heart failure.

Have diabetes or take metformin (Glucophage) for yourdiabetes. You may

have to adjust your medicine for a day before and after the test.

Have had kidney problems.

Have asthma.

Have a medical device, such as a pacemaker or an insulin pump.

Have had multiple myeloma.

Have had an X-ray test using barium contrast material (such as abarium

enema) or have taken a medicine that containsbismuth (such as Pepto-

Bismol) in the past 4 days. Barium and bismuth show up on X-ray films and

make it hard to see the picture clearly.

Become very nervous in small spaces. You need to lie still inside the CT scanner, so

you may need a medicine (sedative) to help you relax.

Arrange for someone to take you home in case you get a medicine to help you relax

(sedative) for the test.

If you have a CT scan of your belly, you may be asked to not eat any solid foods

starting the night before your scan. For a CT scan of the belly, you may drink

contrast material. For some CT scans, you may need a laxative or an enema before

the test.
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Talk to your doctor about any concerns you have regarding the need for the test, its

risks, how it will be done, or what the results will mean. To help you understand the

importance of this test, fill out the medical test information form.

HOW IT IS DONE:

A CT scan is usually done by a radiology technologist. The pictures are usually read

by a radiologist, who writes the report. Other doctors also may review a CT scan.

You may need to take off any jewelry. You will need to take off all or most of your

clothes, depending on which area is studied. You may be able to wear your

underwear for some scans. You will be given a gown to use during the test.

During the test, you will lie on a table that is attached to the CT scanner.

The table slides into the round opening of the scanner, and the scanner moves

around your body. The table will move while the scanner takes pictures. You may

hear a click or buzz as the table and scanner move. It is very important to lie still

during the test.

During the test, you may be alone in the scanning room. But the technologist will

watch you through a window. You will be able to talk to the technologist through atwo-way intercom.

The test will take about 30 to 60 minutes. Most of this time is spent getting ready

for the scan. The actual scan only takes a few seconds.

HOW IT FEELS:

The test will not cause pain. The table you lie on may feel hard, and the room may

be cool. It may be hard to lie still during the test.

Some people feel nervous inside the CT scanner.
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If a medicine to help you relax (sedative) or dye (contrast material) is used, an IV is

usually put in your hand or arm. You may feel a quick sting or pinch when the IV is

started. The dye may make you feel warm and flushed and give you a metallic taste

in your mouth. Some people feel sick to their stomachs or get a headache. Tell the

technologist or your doctor how you are feeling.

RISKS:

The chance of a CT scan causing a problem is small.

There is a chance of an allergic reaction to the dye (contrast material).

If you have diabetes or take metformin (Glucophage), the dye may cause

problems. Your doctor will tell you when to stop taking metformin and when

to start taking it again after the test so you will not have problems. There is a small chance of developing cancer from having some types of CT

scans.1 The chance is higher in children, young adults, and people who have

many radiation tests. If you are concerned about this risk, talk to your doctor

about the amount of radiation this test may give you or your child and

confirm that the test is needed.

There is a slight risk that the CT scan can interfere with implanted or external

medical devices. Examples of medical devices include pacemakers, insulin

pumps, defibrillators, and neurostimulators.

RESULTS:

A computed tomography (CT) scan uses X-rays to make detailed pictures of

structures the inside of the body.

The radiologist may discuss the CT scan with you right after the test.

Complete results usually are ready for your doctor in 1 to 2 days.
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CT SCAN

Normal: The organs and blood vessels are normal in size, shape, and location.

No blood vessels are blocked.

No foreign objects (such as metal or glass fragments), growths (such

as cancer), inflammation, or infection are present.

No bleeding or collections of fluid are present.

Abnormal: An organ is too large or too small, damaged, or infected. Cysts or

abscesses are present.

Foreign objects (such as metal or glass fragments) are present.

Kidney stones orgallstones are present.

Growths (such as tumors) are seen in the colon, lungs, ovaries, liver,

bladder, kidneys, adrenal gland, orpancreas.

A CT scan of the chest shows apulmonary embolism, fluid in the

lungs, or infection.

An aneurysm is present.

Blockage is found in the intestines or in thebile ducts.

A CT of the belly shows inflammatory bowel disease ordiverticulitis.

Lymph nodes are enlarged.

One or more blood vessels are blocked.

A growth, fracture, infection, or other problem is found in an arm or

leg.
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WHAT AFFECTS THE TEST:

The following may stop you from having the test or may change the test results: Pregnancy. CT scans are not usually done during pregnancy.

Barium and bismuth used for another test. These substances show up on a CT

scan. If a CT scan of the belly is needed, it should be done before any tests that

use barium, such as abarium enema.

Metal objects in the body. These items, such as surgical clips or metal in joint

replacements, may prevent a clear view of the body area.

You are not able to lie still during the test.

WHAT TO THINK ABOUT:

Sometimes your CT test results may be different than those from other types of

X-ray tests, magnetic resonance imaging (MRI), orultrasound scans because the

CT scan provides a different view.

An ultrasound test, which doesn't use dangerous radiation, may give results

similar to a CT scan. If you are concerned about radiation exposure, ask your

doctor if you can have an ultrasound instead of a CT scan.

Children who need a CT scan may need special instructions for the test. The

child will likely need to hold his or her breath during the scan. If the child is too

young to hold still or is afraid, the doctor may give the child a medicine

(sedative) to help him or her relax.

If your child is scheduled for a CT scan, talk with your child's doctor about the

need for the scan and the risk of radiation exposure to your child.

Special CT scanners called spiral (helical) CT scanners and multi-slice (or multi-

detector) CT scanners are sometimes used for this test. Many modern scanners

are multi-slice scanners. These scanners can be used for many conditions, such

as finding kidney stones, a pulmonary embolism, an enlargedprostate gland, or

atherosclerosis. These special CT scanners can:

Take better pictures of blood vessels and organs so other imaging tests may not

be needed.

Complete scans and provide pictures in less time.
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CT results are often compared to positron emission tomography (PET) results to

help find cancer. Some new scanners do both scans at the same time.

An electron beam CT scan is another type of CT scan that can find

atherosclerosis and coronary artery disease. An electron beam CT scan is much

faster than a standard CT scan and can take a good picture of a coronary artery

while the heart is beating. Electron beam CT scans are not widely available.

Another type of CT scanner, the multi-slice CT scan, is nearly as fast as electron

beam CT scanners and is more widely available.

A CT angiogram can show two- and three-dimensional pictures of blood vessels.

For more information, see the topic Angiogram of the Head and Neck.

Coronary calcium scans can help find out risk ofheart disease. This test is not

done very often, because aphysical exam and other tests often give enough

information about your heart. This test is not advised for routine screening.

MRI may give different information than a CT scan about certain conditions.

For more information, see the topic Magnetic Resonance Imaging (MRI).

Experts disagree about the use of a CT method called full-body scanning to

screen for coronary artery disease and cancers. Full-body scanning is expensive,

can lead to unnecessary tests or surgery, and may increase the chance of cancer

from the radiation exposure. Most doctors do not recommend these studies

unless a person has a specific risk for a certain disease.
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4.MAGNETIC RESONANCE IMAGING(MRI)

WHAT IS AN MRI SCAN?

An MRI (or magnetic resonance imaging) scan is a radiology technique that uses

magnetism, radio waves, and a computer to produce images of body structures. The

MRI scanner is a tube surrounded by a giant circular magnet. The patient is placed

on a moveable bed that is inserted into the magnet. The magnet creates a strong

magnetic field that aligns the protons of hydrogen atoms, which are then exposed to

a beam of radio waves. This spins the various protons of the body, and they produce

a faint signal that is detected by the receiver portion of the MRI scanner. The

receiver information is processed by a computer, and an image is produced.

The image and resolution produced by MRI is quite detailed and can detect tiny

changes of structures within the body. For some procedures, contrast agents, such as

gadolinium, are used to increase the accuracy of the images.

BASIC COMPONENTS OF MRI MACHINE:

The three basic components of the MRI machine are:

The primary magnet

The largest part of the MRI is the primary magnet. Developing a magnetic field

of adequate strength to create MRI images was an early hurdle to overcome in

the development of this technology.

The gradient magnets

The gradient magnets are the 'fine-tuning' part of the MRI machine. They allow

the MRI to focus on a specific part of the body. The gradient magnets are alsoresponsible for the 'clanging' noise in a MRI.

The coil

Next to the part of your body being imaged is the coil. There are coils made for

shoulders, knees, and other body parts. The coil will emit a radiofrequency that

makes a MRI possible.


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THE PRIMARY MAGNET:

A permanent magnet (like the kind you use on your refrigerator door) powerful

enough to use in a MRI would be too costly to produce and too cumbersome tostore. The other way to make a magnet is to coil electrical wire and run a current

through the wire. This creates a magnetic field within the center of the coil. In order

to create a strong enough magnetic field to perform MRI, the coils of wire must

have no resistance; therefore they are bathed in liquid helium at a temperature 450

degrees Fahrenheit below zero! This allows the coils to develop magnetic fields of

1.5 to 3 Tesla (the strength of most medical MRIs), more than 20,000 times stronger

than the earth's magnetic field.

THE GRADIENT MAGNETS:

There are three smaller magnets within a MRI machine called gradient magnets.

These magnets are much smaller that the primary magnet (about 1/1000 as strong),

but they allow the magnetic field to be altered very precisely. It is these gradient

magnets that allow image "slices" of the body to be created. By altering the gradient

magnets, the magnetic field can be specifically focused on a selected part of the

body.


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THE COIL:

MRI uses properties of hydrogen atoms to distinguish between different tissues

within the human body. The human body is composed primarily of hydrogen atoms

(63%), other common elements are oxygen (26%), carbon (9%), nitrogen (1%), and

relatively small amounts of phosphorus, calcium, and sodium. MRI uses a property

of atoms called "spin" to distinguish differences between tissues such as muscle,

fat, and tendon.

With a patient in a MRI machine, and the magnet turned on, the nuclei of the

hydrogen atoms tend to spin in one of two directions. These hydrogen atom nuclei

can transition their spin orientation, or precess, to the opposite orientation. In order

to spin the other direction, the coil emits a radiofrequency (RF) that causes this

transition (the frequency of energy required to make this transition is specific, and

called the Larmour Frequency).

The signal that is used in creating MRI images is derived from the energy released

by molecules transitioning, or precessing, from their high-energy to their low-

energy state. This exchange of energy between spin states is called resonance, and

thus the name magnetic resonance imaging.

WORKING:

The coil also functions to detect the energy given off by magnetic induction from

the precessing of the atoms. A computer interprets the data, and creates images that

display the different resonance characteristics of different tissue types. We see this

as an image of shades of grey--some body tissues show up darker or lighter, all

depending on the above processes.


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DIFFERENT TYPES OF MRI SCANS:

There are various types of MRI scans that may be ordered by your doctor.

A Head MRI can look at the brain for tumors, an aneurysm, bleeding in the

brain, nerve injury, and other problems, such as damage caused by a stroke.

A head MRI can also find problems of the eyes and optic nerves, and the ears

and auditory nerves.

A Chest MRI can look at the heart, the heart valves, and coronary blood vessels.

It can show if the heart or lungs are damaged. An MRI of the chest may also be

used to look for breast or lung cancer. These can also be ordered after a

mammogram exam has been given to see areas of the breast tissue in more

detail.

MRA or magnetic resonance angiography is a type of magnetic resonance image

(MRI) scan. MRI scans are used to look at blood vessels, and the flow of blood

through them is called magnetic resonance angiography (MRA). MRA scans can

find problems of the arteries and veins, such as an aneurysm, a blocked blood

vessel, or the torn lining of a blood vessel (dissection). Sometimes contrast

material is used to see the blood vessels more clearly. Like an MRI, magnetic

resonance angiograms (MRA) use a magnetic field and pulses of radio wave

energy to make pictures of blood vessels inside the body.

Abdomen and pelvis MRI scans can find problems in the organs and structures

in the belly, such as the liver, gallbladder, pancreas, kidneys, and bladder. They

can be used to find tumors, bleeding, infection, and blockage. In women, MRI

scans can look at the uterus and ovaries. In men, they can look at the prostate.
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Bone and joint MRIs can check for problems such as arthritis, problems with the

temporomandibular joint, bone marrow problems, bone tumors, cartilage

problems, torn ligaments or tendons, or infection. These MRI scans may also be

used to tell if a bone is broken when X-ray results are not clear. MRI scans are

done more commonly than other tests to check for some bone and joint

problems.

A Spine MRI can check the discs and nerves of the spine for conditions such as

spinal stenosis, disc bulges, and spinal tumors.

WHEN ARE MRI SCANS USED?

An MRI scan can be used as an extremely accurate method of disease detectionthroughout the body. In the head, trauma to the brain can be seen as bleeding or

swelling. Other abnormalities often found includebrain aneurysms,stroke, tumors

of the brain, as well as tumors or inflammation of the spine.

Neurosurgeons use an MRI scan not only in defining brain anatomy but in

evaluating the integrity of the spinal cord after trauma. It is also used when

considering problems associated with the vertebrae orintervertebral discs of the

spine. An MRI scan can evaluate the structure of the heart and aorta, where it can

detectaneurysms or tears. It provides valuable information on glands and organs

within the abdomen, and accurate information about the structure of the joints, soft

tissues, and bones of the body. Often, surgery can be deferred or more accurately

directed after knowing the results of an MRI scan.
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WHY IT IS DONE:

Magnetic resonance imaging (MRI) is done for many reasons. It is used to findproblems such as tumors, bleeding, injury, blood vessel diseases, or infection. MRI

also may be done to provide more information about a problem seen on an X-ray,

ultrasound scan, or CT scan. Contrast material may be used during MRI to show

abnormal tissue more clearly. An MRI scan can be done for the:

HeadMRI can look at the brain for tumors, an aneurysm, bleeding in the

brain, nerve injury, and other problems, such as damage caused by a stroke. MRI

can also find problems of the eyes and optic nerves, and the ears and auditory

nerves. ChestMRI of the chest can look at the heart, the valves, and coronary blood

vessels. It can show if the heart orlungs are damaged. MRI of the chest may also

be used to look forbreast orlung cancer.

Blood vesselsUsing MRI to look at blood vessels and the flow of blood

through them is called magnetic resonance angiography (MRA). It can find

problems of the arteries and veins, such as an aneurysm, a blocked blood vessel,

or the torn lining of a blood vessel (dissection). Sometimes contrast material is

used to see the blood vessels more clearly.

Abdomen and pelvisMRI can find problems in the organs and structures in

the belly, such as the liver, gallbladder,pancreas, kidneys, andbladder. It is used

to find tumors, bleeding, infection, and blockage. In women, it can look at the

uterus and ovaries. In men, it looks at theprostate.

Bones and jointsMRI can check for problems of the bones and joints, such as

arthritis, problems with the temporomandibular joint,bone marrow problems,

bone tumors, cartilage problems, torn ligaments ortendons, or infection. MRI

may also be used to tell if a bone is broken when X-ray results are not clear.

MRI is done more commonly than other tests to check for some bone and joint

problems.

SpineMRI can check the discs and nerves of the spine for conditions such as

spinal stenosis, disc bulges, and spinal tumors.
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HOW DOES A PATIENT PREPARE FOR AN MRI SCAN AND

HOW IS IT PERFORMED?

All metallic objects on the body are removed prior to obtaining an MRI scan.Occasionally, patients will be given a sedative medication to decrease anxiety and

relax the patient during the MRI scan. MRI scanning requires that the patient lie

still for best accuracy. Patients lie within a closed environment inside the magnetic

machine. Relaxation is important during the procedure and patients are asked to

breathe normally. Interaction with the MRI technologist is maintained throughout

the test. There are loud, repetitive clicking noises which occur during the test as the

scanning proceeds. Occasionally, patients require injections of liquid intravenously

to enhance the images which are obtained. The MRI scanning time depends on the

exact area of the body studied, but ranges from half an hour to an hour and a half.

HOW IT FEELS:

You will not have pain from the magnetic field or radio waves used for the MRI

test. The table you lie on may feel hard and the room may be cool. You may be

tired or sore from lying in one position for a long time.

If a contrast material is used, you may feel some coolness and flushing as it is put

into your IV.

In rare cases, you may feel:

A tingling feeling in the mouth if you have metal dental fillings.

Warmth in the area being examined. This is normal. Tell the technologist if you

have nausea, vomiting, headache, dizziness, pain, burning, orbreathing

problems.

RISKS:

An MRI scan is a painless radiology technique that has the advantage of avoiding x-

ray radiation exposure. There are no known side effects of an MRI scan. The

benefits of an MRI scan relate to its precise accuracy in detecting structural

abnormalities of the body.
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Patients who have any metallic materials within the body must notify their

physician prior to the examination or inform the MRI staff. Metallic chips,

materials, surgical clips, or foreign material (artificial joints, metallic bone plates, or

prosthetic devices, etc.) can significantly distort the images obtained by the MRI

scanner. Patients who have heart pacemakers, metal implants, or metal chips or

clips in or around the eyeballs cannot be scanned with an MRI because of the risk

that the magnet may move the metal in these areas. Similarly, patients with artificial

heart valves, metallic ear implants, bullet fragments, and chemotherapy orinsulin

pumps should not have MRI scanning.

During the MRI scan, patient lies in a closed area inside the magnetic tube. Some

patients can experience a claustrophobic sensation during the procedure. Therefore,

patients with any history ofclaustrophobia should relate this to the practitioner who

is requesting the test, as well as the radiology staff. A mild sedative can be given

prior to the MRI scan to help alleviate this feeling. It is customary that the MRI

staff will be nearby during MRI scan. Furthermore, there is usually a means of

communication with the staff (such as a buzzer held by the patient) which can be

used for contact if the patient cannot tolerate the scan.

There are no known harmful effects from the strong magnetic field used for MRI.

But the magnet is very powerful. The magnet may affect pacemakers, artificiallimbs, and other medical devices that contain iron. The magnet will stop a watch

that is close to the magnet. Any loose metal object has the risk of causing damage

or injury if it gets pulled toward the strong magnet.

Metal parts in the eyes can damage the retina. If you may have metal fragments in

the eye, an X-ray of the eyes may be done before the MRI. If metal is found, the

MRI will not be done.Iron pigments in tattoos or tattooed eyeliner can cause skin or

eye irritation.An MRI can cause a burn with some medication patches. Be sure to

tell your health professional if you are wearing a patch. There is a slight risk of an

allergic reaction if contrast material is used during the MRI. But most reactions are

mild and can be treated using medicine.

There also is a slight risk of an infection at the IV site.
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RESULTS:

A magnetic resonance imaging (MRI) is a test that uses a magnetic field and pulses

of radio wave energy to make pictures of organs and structures inside the body.

The radiologist may discuss initial results of the MRI with you right after the test.Complete results are usually ready for your doctor in 1 to 2 days.An MRI can

sometimes find a problem in a tissue or organ even when the size and shape of the

tissue or organ looks normal.

MAGNETIC RESONANCE IMAGING (MRI)

Normal: The organs, blood vessels, bones, and joints are normal in size, shape,

appearance, and location.

No abnormal growths, such as tumors, are present.

No bleeding, abnormal fluid, blockage in the flow of blood, or bulges

in the blood vessels (aneurysms) are present.

No signs of inflammation or infection are present.

Abnormal: An organ is too large, too small, damaged, or absent.

Abnormal growths (such as tumors) are present.

Abnormal fluid from a cause such as bleeding or an infection is

present. Fluid is found around the lungs or heart. Fluid is found around

the liver, bowel, or other organ in the abdomen.

A blood vessel is narrowed or blocked. An aneurysm is present.

Blockage in the gallbladderbile ducts or in the tubes (ureters) that lead

out of the kidneys is present.

Damage tojoints, ligaments, orcartilage is seen. Bones are broken or

show infection or disease.

Problems of the nervous system are present, such as multiple sclerosis
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(MS), dementia, Alzheimer's disease, orherniated disc.

HOW DOES A PATIENT OBTAIN THE RESULTS OF THE MRI

SCAN?

After the MRI scanning is completed, the computer generates visual images of the

area of the body that was scanned. These images can be transferred to film (hard

copy). A radiologist is a physician who is specially trained to interpret images of the

body. The interpretation is transmitted in the form of a report to the practitioner

who requested the MRI scan. The practitioner can then discuss the results with the

patient and/or family.

FUTURE:

Scientists are developing newer MRI scanners that are smaller, portable devices.

These new scanners apparently can be most useful in detecting infections and

tumors of the soft tissues of the hands, feet, elbows, and knees. The application of

these scanners to medical practice is now being tested.
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5.X-RAY

DEFINITION:

X rays are electromagnetic radiation that differentially penetrates structures within

the body and creates images of these structures on photographic film or a

fluorescent screen. These images are called diagnostic x rays.

PURPOSE:

Diagnostic x rays are useful in detecting abnormalities within the body. They are a

painless, non-invasive way to help diagnose problems such as broken bones,

tumors, dental decay, and the presence of foreign bodies.

DESCRIPTION:

X rays are a form of radiation similar to light rays, except that they are more

energetic than light rays and are invisible to the human eye. They are created when

an electric current is passed through a vacuum tube. X rays were accidentally

discovered in 1895 by German physicist Wilhem Roentgen (1845-1923), who was

later awarded the first Nobel Prize in physics for his discovery. Roentgen was also a

photographer and almost immediately realized that the shadows created when x rays

passed through the body could be permanently recorded on photographic plates. His

first x-ray picture was of his wife's hand. Within a few years, x rays became a

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HOW X RAYS WORK :

X rays pass easily through air and soft tissue of the body. When they encountermore dense material, such as a tumor, bone, or a metal fragment, they are stopped.

Diagnostic x rays are performed by positioning the part of the body to be examined

between a focused beam of x rays and a plate containing film. This process is

painless. The greater the density of the material that the x rays pass through, the

more rays are absorbed. Thus bone absorbs more x rays than muscle or fat, and

tumors may absorb more x rays than surrounding tissue. The x rays that pass

through the body strike the photographic plate and interact with silver molecules on

the surface of the film.

nce the film plates have been processed, dense material such as bone shows up as

white, while softer tissue shows up as shades of gray, and airspaces look black. A

radiologist, who is a physician trained to interpret diagnostic x rays, examines the

pictures and reports to the doctor who ordered the tests. Plain film x rays normally

take only a few minutes to perform and can be done in a hospital, radiological

center, clinic, doctor's or dentist's office, or at bedside with a portable x-ray

machine.


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SPECIAL TYPES OF X-RAY PROCEDURES:

Mammograms are fixed plate x rays that are designed to locate tumors within thebreasts. Dental x rays are designed to locate decay within the tooth. Sometimes a

liquid called contrast material (for example, barium) is used to help outline internal

organs such as the intestines. The contrast material absorbs x rays, helping to make

soft tissue more easily visible on the x-ray films. Contrast material is commonly

used in making x rays of the digestive system. The contrast liquid can be swallowed

or injected, depending on the part of the body being x rayed. This may cause some

minor discomfort.

Fluoroscopy is a special x-ray technique that produces real-time images on a

television monitor. With fluoroscopy, contrast material is injected into a blood

vessel. The physician can then watch the real-time movement of the contrast

material to determine if there are blockages in circulation. Fluoroscopy is also used

to help guide catheters into place in the heart during cardiac catheterization or to

guide an endoscope during endoscopic surgery.

Computed tomography or CT scan works on the same principles as fixed plate xrays, only with a CT scan, an x ray tube rotates around the individual, taking

hundreds of images that are then compiled by a computer to produce a two-

dimensional cross section of the body. Although many images are taken to produce

a CT scan, the total dose of radiation the individual is exposed to is low. Other

common imaging techniques such as magnetic resonance imaging (MRI) and

ultrasound do not use x rays.

HOW X RAYS ARE PERFORMED:

Fixed plate x rays are extremely common diagnostic tests. A trained x-ray

technologist takes the x ray. The individual is first asked to remove clothing and

jewelry and to wear a hospital gown. The x ray technologist positions the patient

appropriately, so that the part of the body to be x rayed will be between the x-ray

beam and the film plate. Usually the individual either lies on an adjustable table or

stands.
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Parts of the body that are especially sensitive to damage by x rays (for example, the

reproductive organs, the thyroid) are shielded with a lead apron. Lead is very dense

and effectively protects the body by stopping all x rays.

It is essential to remain motionless during the x ray, since movement causes theresulting picture to be blurry. Sometimes patients are asked to hold their breath

briefly during the procedure.

Children who are not old enough follow directions or who cannot stay still may

need to be restrained or given medication to sedate them in order to keep them still

enough to obtain useful results. Sometimes parents can stay with children during an

x ray, unless the mother is pregnant, in which case she must protect the fetus from

x-ray exposure.

If a contrast material is to be used, the individual will be given special instructions

to prepare for the procedure and may be asked to remain afterwards until recovery

is complete. (See Preparation and Aftercare below.)

PRECAUTIONS :

Although unnecessary exposure to radiation should be avoided, the low levels of

radiation one is exposed to during an x ray does not cause harm with a few

exceptions. Pregnant women should not have x rays unless in emergencies the

benefits highly outweigh the risks. Exposure of the fetus to x rays, especially during

early pregnancy can increase the risk of the child later developing leukemia. Body

parts not being x rayed should be shielded with a lead apron, especially the testes,

ovaries, and thyroid.

PREPARATION :

No special preparation is needed for fixed plate x rays unless contrast material is

used. When x rays are scheduled that involve the use of contrast material, the

physician will give specific instructions for preparation. For example, in a lower GI

series, the individual may have to fast and use special laxatives to cleanse the

bowel before swallowing the contrast material.
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KEY TERMS:

Contrast agentAlso called a contrast medium, this is usually a barium or iodine

dye that is injected into the area under investigation. The dye makes the interior

body parts more visible on an x-ray film.

Electromagnetic radiationPackets of energy that develop when an electric

current passes through a vacuum tube.

EndoscopeA medical instrument that can be passed into an area of the body (the

bladder or intestine, for example) to allow visual examination of that area. The

endoscope usually has a fiberoptic camera that allows a greatly magnified image to

be shown on a television screen viewed by the operator. Many endoscopes alsoallow the operator to retrieve a small sample (biopsy) of the area being examined, to

more closely view the tissue under a microscope.

RISKS:

Low dose exposure to x rays creates minimal cell damage and minimal risk when x

rays are performed in an accredited facility. There is an increased risk that a

developing fetus will develop leukemia during childhood if exposed to x-ray

radiation; pregnant or potentially pregnant women should avoid x rays. There is

also a slight risk of an allergic reaction to the contrast material or dye used in

certain x rays.


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6.ECHOCARDIOGRAM AND TMT

ECHOCARDIOGRAM:

Echocardiogram, often referred to cardiac echo or simply an echo is

a sonogram of the heart. (It is not abbreviated as ECG, which in medicine usually

refers to an electrocardiogram.) Echocardiography

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