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Right option is (a) TRUE

The explanation is: It is true. In the whole BODY, there are about 25 billion erythrocytes and they are constantly being destroyed and replaced at a rate of about 9000 million per hour.There are about 5.5 million of them in every cubic millimetre of blood in MEN and nearly 5 million in WOMEN.

Correct choice is (a) Mean Platelet VOLUME

To elaborate: Mean Platelet Volume (MPV) is the RATIO of the integrated platelet volume to the platelet count and is expressed in FEMOLITRES. Red CELL Distribution Width is a numerical expression of the width of the size distribution of red cells. Platelet Distribution Width is related to the size range covered by those platelets lying between the sixteenth and eighty fourth percentile.

Correct option is (d) erythrocytes

Explanation: Red blood cells have the form of a bi-concave disc with a MEAN diameter of about 7.5 m and THICKNESS of about 1.7 m. The mean surface AREA of the CELL is about 134mm^2. There are about 5.5 MILLION of them in every cubic millimetre of blood in men and nearly 5 million in women.

Correct answer is (b) Monocytes > Neutrophils > RBC >= lymphocytes

The EXPLANATION is: Monocytes are twice as BIG as neutrophils. Neutrophils are twice as big as the RBC. The lymphotocytes are of ALMOST of the same SIZE of the RBC of smaller.

Right CHOICE is (c) optical fibre

Best explanation: For INTRAVASCULAR oximetry, modern instruments make use of optical fibres to guide the light signal inside the vessel and the REFLECTED light from the RED blood cells back to the light detector.

Correct answer is (B) False

For EXPLANATION I would say: It is false. Neutrophils are NEARLY twice as big as the red cells. Theycontain both a NUCLEUS divided into several lobes and GRANULES in their protoplasm. Lymphocytes are of the same size as the red cells but contain a large density staining nucleus and no granules.

Right ANSWER is (b) 2

To explain I WOULD say: For estimating SO2, usually the REFLECTANCE at two wavelengths, one in the RED and the other in the near infrared REGIONS, are used.

The correct option is (a) True

Explanation: LEUCOCYTES form the defence mechanism of the body against infection. They are of two main types: the neutrophils and the lymphocytes. Neutrophils ingest BACTERIA and lymphocytes are concerned with immunological RESPONSE. The number and proportion of these types of leucocytes may vary widely in response to VARIOUS disease CONDITIONS.

Right choice is (d) 120

Explanation: The normal RED cell LASTS approximately 120 days before it is destroyed. There are about 5.5 million of them in every cubic millimetre of BLOOD in men and nearly 5 million in women. In the whole BODY, there are about 25 billion erythrocytes and they are CONSTANTLY being destroyed and replaced at a rate of about 9000 million per hour.

Correct choice is (a) [(20th – 80th) Percentile Volume / (20th + 80th) Percentile Volume] X 100 X K

The explanation: The RDW index is expressed by the following equation [(20th – 80th) Percentile Volume / (20th + 80th) Percentile Volume] X 100 X K. It is a numerical expression of the width of the size distribution of red cells. It is derived by ANALOG computation. The total ERYTHROCYTE count is scanned by a CONTINUOUSLY variable thresholding circuit. The upper threshold is moved progressively lower from a level equivalent to 360 femolitres until 20 PERCENT of all erythrocytes present have a size above a certain value.

The CORRECT option is (c) Plateletcrit

Explanation: The percentage of the total specimen volume occupied by the PLATELETS is called.Mean Platelet Volume is the ratio of the INTEGRATED platelet volume to the platelet count and is expressed in femolitres. Red Cell Distribution Width is a numerical EXPRESSION of the width of the SIZE distribution of red cells.

Right OPTION is (a) haematocrit value

The best I can explain: The percentage of cells in the blood is called the haematocrit value or packed cell volume (PCV). The majority of the CORPUSCLES in the blood are red blood cells (ERYTHROCYTES), others being white blood cells (leucocytes) and platelets (thrombocytes).

Correct choice is (b) False

The best explanation: The erythrocytes have no nucleus. They are responsible for carrying OXYGEN from the lungs to the tissues and carbon dioxide from the tissues to the lungs. In the whole BODY, there are about 25 billion erythrocytes and they are constantly being destroyed and replaced at a rate of about 9000 million PER hour.

Right CHOICE is (a) More than 2

The best explanation: For estimating SO2, usually the reflectance at two wavelengths, one in the RED and the other in the near infrared REGIONS, are used. CURRENTLY available fiber-optic oximeters utilize more than two wavelengths to adjust for haematocrit variation.

The CORRECT answer is (a) True

The BEST explanation: It is true. Normal MEAN cell HAEMOGLOBIN is 29.5 ± 2.5 pg. In diseased conditions it may rise to 50 pg or fall to 15 pg.

Right answer is (b) in the oxygen CARRYING capacity of blood

To explain: Anaemia is a reduction in the oxygen carrying capacity of the blood. It can develop from a change in the number, VOLUME or Hb concentration of erythrocytes, caused by bone marrow dysfunction resulting in the POOR production rate of RBCS. Since these changes are specific, the measurement of PACKED cell volume (PCV), the number of RBCs and the haemoglobin (Hb) are very important.

The CORRECT CHOICE is (a) HEATER

The best explanation: A heater was incorporated in the sensor to WARM the tissue so as to increase local blood flow. Excellent correlation in comparison with the TRANSMISSION oximeter has been shown from the calf and thigh.

Correct choice is (C) ear

Best explanation: BLOOD in the ear MUST be made similar to arterial blood in COMPOSITION. This is done by increasing the flow through the ear without appreciably increasing the metabolism. Maximum vasodilatation is achieved by keeping the ear warm.

The correct option is (C) Spherical

For explanation: Leucocytes are spherical cells having a nucleus. There are normally 5000–10,000 white cells per cubic mm of BLOOD but their NUMBER varies during the day. They live for seven to fourteen days and there is a RAPID turn over, with constant destruction and REPLACEMENT.

Right OPTION is (b) If it is LESS than 85% of the predicted interval

Explanation: In timing classification, the observed R-R interval is compared to an estimate of the expected R-R interval. An R-R interval will be declared PREMATURE if it is less than 85% of the predicted interval. Similarly, an R-R interval is long if it is greater than 110% of the predicted VALUE.

Right answer is (a) True

Easy EXPLANATION: The instrument is based on the Beer-Lambert law. HOWEVER, it is assumed that the optical absorbers act INDEPENDENTLY and additively and that the effects of light scattering by the ear TISSUE can be minimized by a proper source and detector GEOMETRY.

The correct CHOICE is (c) 2.5

Best explanation: A 2.5 m long flexible fibre ear probe connects the patient to the instrument. The ear probe can be either HELD in position for discrete measurements or can be conveniently mounted to a headband for CONTINUOUS DISPLAY.

The correct choice is (a) True

Easiest explanation: In a floating ELECTRODE, the metal electrode does not make DIRECT contact with the skin. The electrode consists of a light weighted metalled screen or plate held AWAY from the subject by a flat washer which is connected to the skin. Floating ELECTRODES can be recharged, i.e. the jelly in the electrodes can be replenished if desired.

Correct option is (C) Skin REFLECTANCE Oximeter

The EXPLANATION: For the measurement of oxygen saturation LEVEL of blood in localized areas of oxygen DEPRIVED tissues on the limbs, head and torso, a skin reflectance oximeter can be employed.

The correct answer is (b) SO2

For explanation: A PAIR of red and INFRARED light emitting diodes is used for the light source, with peak emission wavelengths of 665 nm (red) and 935 nm (infrared). The reflected light from the skin at these two wavelengths is DETECTED by a silicon diode. These detected signals are processed in the form of photo-plethysmographs to determine So2.

The CORRECT option is (a) (concentration of OXYHAEMOGLOBIN/{concentration of oxyhaemoglobin+ concentration of deoxyhaemoglobin})*100

For explanation: The instrument is designed to MEASURE the PERCENTAGE of functional hemoglobin COMBINED with oxygen. This can be expressed as:

where CO is the concentration of oxyhemoglobin and CR is the concentration of deoxyhemoglobin.

The correct option is (a) True

The explanation: Arrhythmia monitors require RELIABLE R wave detectors as a PREREQUISITE for SUBSEQUENT analysis. The steep, large amplitude variation of the QRS COMPLEX is the obvious characteristics to use and this is the function of the R wave detector.

Correct option is (B) SOPHISTICATED alarm system

Explanation: An arrhythmia monitor is BASICALLY a sophisticated alarm system. It is not an ECG interpretation system. It constantly scans ECG rhythm patterns and issues alarms to events that may be premonitory or life threatening.

Correct OPTION is (B) Pulse

Easy explanation: Components of pulse OXIMETER PROBE.

Correct answer is (b) 12 bit

Explanation: In signal CONDITIONING, ECG signal is amplified, filtered and DIGITIZED using an 8 or 12 bit analog-to-digital CONVERTER with a typical SAMPLING rate of 250 Hz.

The CORRECT option is (a) Rhythm definition

For explanation I would say: In automated arrhythmia monitoring system, Rhythm definition is performed after the VENTRICULAR fibrillation detection. Rhythm definition is also performed after the beat LABELING and ATRIAL fibrillation detection in automated arrhythmia monitoring and analysis system.

Correct answer is (a) 0.05-150 HZ

To explain I would say: The diagnostically useful frequency range is usually accepted as 0.05 to 150 Hz. Although the electric FIELD generated by the heart can be best characterized by vector quantities, it is generally convenient to directly measure only scalar quantities, i.e. a voltage DIFFERENCE of MV ORDER between the given points of the body.

The correct option is (b) Red and infrared LED’s

To explain: A pair of red and infrared light emitting DIODES are used for the light SOURCE, with peak EMISSION WAVELENGTHS of 665 nm (red) and 935 nm (infrared). The reflected light from the skin at these two wavelengths is detected by a silicon diode.

The correct choice is (a) True

Easiest explanation: The instrument is based on the Beer-Lambert law. However, it is ASSUMED that the optical ABSORBERS act independently and additively and that the effects of light scattering by the ear TISSUE can be minimized by a proper source and detector GEOMETRY.

Right option is (a) 250 Hz

To elaborate: In signal conditioning, ECG signal is amplified, filtered (0.05-100 Hz for diagnostic purposes, 1-40 Hz for monitoring purposes) and DIGITIZED USING an 8 or 12-bit analog-to-digital converter with a TYPICAL SAMPLING rate of 250 Hz.

Correct option is (B) False

The explanation is: ECG SIGNAL is amplified and filtered with 0.05-100 Hz for diagnostic PURPOSES and 1-40 Hz for monitoring purposes in signal conditioning.

Right answer is (b) EAR

For explanation: MERRICK and Hayes (1976) describe details of an ear OXIMETER which enables the MEASUREMENT of oxygen saturation of blood. This measurement is independent of a wide range of encountered variables and is made without involving patients in any CALIBRATION or standardization procedure.

Correct OPTION is (b) Cepstrum coefficient and Dynamic time warping

Easy explanation: Jen and Hwang proposed a new algorithm using cepstrum coefficient and the dynamic time warping techniques to obtain the long term ECG signal feature and EXTRACT the meaningful information hiding in the QRS complex. This algorithm may ALSO be used for arrhythmia detection by simply checking the difference of R-R wave INTERVALS through signal feature extraction comparison for a certain period of time.

Right CHOICE is (c) Low FREQUENCY noise, MOTION noise

To elaborate: The ECG waveform is processed by two DIGITAL filters: a detection FILTER and a classification filter. The detection filter removes low frequency noise (baseline wander) and muscle artifact. P waves and T waves are diminished.

Right choice is (c) Tungsten-iodine lamp

Easy explanation: The light source is a tungsten-iodine lamp that has a high output in the SPECTRUM of interest. A lens system collimates the light beam and DIRECTS it through thin-film interference filters that PROVIDE WAVELENGTH selection.

Correct answer is (B) Morphology characterization

To EXPLAIN I would say: Morphology characterization is based on analyzing the shape of the QRS complexes and separating beats into GROUPS or clusters of similar morphology. Most algorithms for real time arrhythmia analysis MAINTAIN no more than 10-20 clusters at a time, order to limit the AMOUNT of computation needed to assign a QRS complex to a cluster.