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The correct CHOICE is (c) 16th and 84th percentile

Explanation: Platelet DISTRIBUTION Width (PDW): This index is related to the SIZE range covered by those PLATELETS lying between the sixteenth and eighty fourth percentile. This is the conventional geometric standard deviation of the MEAN platelet size and is derived from the distribution curve based on the data in a 64-channel pulse height analyzer.

The CORRECT option is (a) 30 sec

The best I can explain: Instruments based on this automatic optical TECHNIQUE take about 30 s for completing the count. An accuracy of 2% is attainable. The instruments require about 1 ml of the BLOOD sample.

Correct answer is (b) + or – 17%

To elaborate: Agoston and Zillich (1971) COMPARED the results of microscopic counting with those made by electronic COUNTERS. It may be observed that INSTEAD of the + 0r – 20% MEASURING accuracy in microscopic counting, the electronic counters can provide an accuracy of + or – 3%.

Correct ANSWER is (c) RBC

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. Anaemia (reduction in the oxygen carrying capacity of blood) 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.

Correct option is (c) foetus

For EXPLANATION: In external toco-tonometry, movement of the foetus MAY be superimposed on the labour activity curve. Stress imposed on the FOETAL CIRCULATORY system by the UTERINE contractions, foetal movements or other factors are seen in the response of the foetal heart to these stimuli and are studied in the correct time relationship.

Right CHOICE is (a) Incident light Intensity

The best explanation: A pulse oximeter shows the percentage of arterial HEMOGLOBIN in the OXYHEMOGLOBIN (HbO2) and hemoglobin (Hb). This observation A = -logT = log I0/I = ɛDC where Io and I are incident and transmitted light intensities, e is the EXTINCTION coefficient, D is the depth of the absorbing layer and C is concentration.

Correct option is (b) FALSE

Explanation: False, Signal processing for FHR determination can be based either on detecting the foetal heart valve motion or on detecting the heart wall motion in Ultrasound technique as The heart valve motion detection technique is based on the DISTINCT ultrasound frequency shift produced by the fast opening and closing of the heart valves. The technique, however, requires that the ultrasound beam must be DIRECTED against the relatively small heart valves involving a longer search period and frequent repositioning of the transducer. Therefore, it is not PREFERRED for continuous monitoring applications.

Right answer is (d) 20th week

For explanation: BLOOD flow detectors based on ultrasonic Doppler shift can detect foetal pulse as early as the tenth week of pregnancy and in nearly all cases by the twelfth week. At about 20 WEEKS it is possible to detect multiple pregnancies especially if TWO instruments are USED together and the pulse rates compared. Intrauterine death of the foetus can also be diagnosed.

The correct answer is (a) Erythrocytes

Easy explanation: Erythrocytes (Red Blood Cells): 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 134mm2. There are about 5.5 million of them in every cubic millimetre of blood in men and nearly 5 million in WOMEN.

Right choice is (b) two

For explanation: Instantaneous “beat-to-beat” rate is displayed on a calibrated linear scale or digitally displayed with a RANGE from 50 to 210 BPM. A two-channel chart recorder is incorporated in instruments USED for monitoring labour activity. One channel RECORDS FHR on a calibrated chart in beats per minute (50–210 bpm) while the other channel is used for RECORDING uterine contractions calibrated 0-100 mmHg.

The correct option is (c) beats/min

For explanation: A two-channel CHART recorder is incorporated in instruments used for MONITORING labour ACTIVITY. One channel records FHR on a calibrated chart in beats per MINUTE (50–210 bpm) while the other channel is used for recording uterine contractions calibrated 0-100 mmHg. The standard chart speed is usually 1 or 2 cm/min.

The correct choice is (c) Extinction coefficient

Best EXPLANATION: A pulse oximeter shows the percentage of arterial hemoglobin in the OXYHEMOGLOBIN (HbO2) and hemoglobin (Hb). This observation A = -logT = log I0/I = ɛDC where IO and I are incident and transmitted light intensities, E is the extinction coefficient, D is the depth of the absorbing layer and C is concentration.

Right choice is (a) IUP

The best I can explain: The internal method measures intra-uterine pressure (IUP) via a fluid-filled catheter. The catheter is inserted into the uterus through a guide after the rupture of the foetal membranes. After allowing free flow of amniotic fluid to ENSURE correct placement, the DISTAL end of the catheter is usually attached to a pressure TRANSDUCER of the type used for cardiac studies.

The correct choice is (b) 30 to 70 s

Easiest explanation: During labour, the uterus muscle starts contractions of increasing intensity in a bid to expel out the child. The intrauterine pressure can reach values of 150 MMHG or more during the expulsion period. However, a NORMAL patient in spontaneous active labour will demonstrate UTERINE contractions occurring at INTERVALS of three to five minutes, with a duration of 30 to 70 s and a peak intensity of 50 to 75 mmHg.

Correct option is (c) 25 mm

Easiest explanation: The narrow BEAM transducer uses a single ultrasound transmitter/receiver piezo-electric CRYSTAL pair. The maximum ultrasound INTENSITY is generally kept below 25 mW/cm2. The TYPICAL transducer DIAMETER is 25 mm. The narrow beam transducer is very sensitive and produces a good trigger signal for instantaneous heart rate determination.

Correct ANSWER is (d) Mixing coils and delay coils

The best explanation: TWO types of coils are employed in the system—mixing coils and delay coils. Coils are glass spirals of critical dimensions, in which the mixing liquids are inverted several times, so that complete mixing can RESULT. Mixing coils are used to mix the sample and/or reagents. Delay coils are employed when a specimen must be delayed for the completion of a chemical reaction before reaching the colorimeter.

Right choice is (b) Strain guage

Explanation: The transducer carries a protruding TIP which is PRESSED to the MOTHER’s abdomen with a light force to ensure an EFFECTIVE coupling. The protruding surface of the transducer is displaced as the tension in the uterus increases. This movement is converted into an electrical signal by a strain gauge in the transducer housing. The abdominal transducer provides a reliable indication of the occurrence frequency, duration and relative intensity of the contraction.

The correct option is (a) piezo-electric

To elaborate: The broad BEAM transducers are available in many configurations. The transducers COMPRISE a number of piezo-electric crystals mounted in such a way as to be able to detect foetal heart MOVEMENTS over a wider AREA.

The CORRECT ANSWER is (b) MCHC

For EXPLANATION I would say: It can be calculated if PCV and Hb PER dl are known. For example, if PCV is 0.45 and there are 15 g Hb per dl of BLOOD, then

MCHC = (15 /0.45) g/dl

= 33.3 g/dl.

The correct answer is (c) 5 to 7 minutes

The best explanation: During labour, the uterus muscle starts CONTRACTIONS of increasing intensity in a bid to EXPEL out the child. The intrauterine pressure can reach values of 150 mmHg or more during the EXPULSION period. However, a normal patient in spontaneous active labour will demonstrate UTERINE contractions occurring at intervals of three to five minutes, with a duration of 30 to 70 s and a peak intensity of 50 to 75 mmHg.

The correct option is (d) 1:50000

Easiest EXPLANATION: The method is based on collecting scattered light from the blood CELLS and converting them into electrical pulses for COUNTING. A sample of dilute blood (1:500 for white cells and 1:50,000 for red cells) is taken in a GLASS container. It is drawn through a counting CHAMBER in which the blood stream is reduced in cross-section by a concentric high velocity liquid sheath.

The correct choice is (d) Polystyrene cups

For explanation: The unit in its EARLIER FORM consisted of a circular turntable carrying around its rim 40 disposable polystyrene cups of 2 ml capacity. The SAMPLE plate carrying these cups rotates at a predetermined speed. The movement of the turntable is SYNCHRONIZED with the movements of a sampling CROOK.

Right CHOICE is (a) Pulse Oximeter

To explain: Because of their simplicity of use and the ability to PROVIDE continuous and immediate oxygen saturation values, pulse oximeters are of critical importance in emergency medicine and are also very useful for patients with respiratory or CARDIAC problems, especially COPD, or for DIAGNOSIS of some sleep DISORDERS such as apnea and hypopnea.

The correct answer is (a) 0-100 mm Hg

The EXPLANATION is: A two-channel chart recorder is incorporated in INSTRUMENTS used for monitoring labour activity. ONE channel records FHR on a calibrated chart in beats per minute (50–210 bpm) while the other channel is used for RECORDING uterine contractions calibrated 0-100 MMHG. The standard chart speed is usually 1 or 2 cm/min.

Correct choice is (b) FALSE

Explanation: False, the ultrasonic transducer is arranged in the shape of a clover-leaf so that it provides a large area of ultrasonic illumination which allows the monitoring considerable lateral and descending foetal motion before requiring repositioning. The ultrasonic transducer housing is flexible to PERMIT it to FOLLOW the contour of the ABDOMEN regardless of shape CHANGES with contractions.

Right choice is (d) Sampler

Easiest explanation: The automated SYSTEM consists of a group of modular instruments INTERCONNECTED together by a MANIFOLD system and electrical systems. The sample to be analyzed is introduced into a stream of diluting liquid flowing in the narrow bore of a flexible plastic tube. The STAGES of the ANALYTICAL reaction are completed by the successive combination of other flowing streams of liquids with the sample stream, by means of suitably shaped glass functions.

The correct answer is (C) 5-6 liters

The explanation is: The blood constitutes 5–10% of the total BODY weight and in the average adult, it amounts to 5–6 l. Blood consists of corpuscles suspended in a fluid called plasma in the proportion of 45 PARTS of corpuscles (cells) to 55 parts of plasma.

The correct choice is (b) False

Explanation: False, pulse oximetry is a non-invasive method ALLOWING the monitoring of the saturation of a patient’s HEMOGLOBIN. A pulse OXIMETER shows the percentage of arterial hemoglobin in the oxyhemoglobin (HbO2) and hemoglobin (Hb). These OBSERVATIONS:

A = -logT = log I0/I =ɛDC.

Right answer is (a) 2 cm/min

For explanation I would SAY: A two-channel chart RECORDER is incorporated in instruments USED for monitoring labour activity. One channel records FHR on a calibrated chart in beats per minute (50–210 BPM) while the other channel is used for recording uterine contractions calibrated 0-100 mmHg. The standard chart speed is usually 1 or 2 cm/min.

The correct choice is (c) 150 MM Hg

The explanation: During labour, the uterus muscle starts contractions of increasing intensity in a bid to expel out the child. The intrauterine pressure can REACH VALUES of 150 mmHg or more during the expulsion period. However, a NORMAL patient in spontaneous active labour will demonstrate uterine contractions occurring at intervals of three to five minutes, with a duration of 30 to 70 s and a PEAK intensity of 50 to 75 mmHg.

Correct CHOICE is (a) True

To elaborate: True, The narrow beam transducer is very sensitive and produces a good TRIGGER SIGNAL for instantaneous heart rate determination because it takes time to detect a good signal and, THEREFORE, FREQUENT transducer repositioning is necessary.

Correct option is (a) True

To explain: True, the transmitting crystal emits a 40° divergent beam so that at 10 CM from the SKIN surface the beam covers an area of approximately 10 cm diameter. This construction ensures continuous recording of the foetal heart ACTIVITY without the need to reposition the transducer which is otherwise necessitated due to normal foetal movement. The transducer has a diameter of 6 cm and can be held in PLACE either by a simple buckle or a stretch belt.

Right ANSWER is (d) 40°

The explanation: An alternative arrangement is the array transducer which has one TRANSMITTER and six peripheral ceramic receiving crystals. The transmitting crystal EMITS a 40° divergent BEAM so that at 10 cm from the skin surface the beam covers an area of approximately 10 cm diameter.

The correct choice is (b) The lymphocytes and the neutrophils

The EXPLANATION is: 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 an immunological RESPONSE.

Right answer is (a) PLATELETS

The best I can explain: Platelets are USUALLY tiny, round, oblong or IRREGULARLY shaped cells of the blood with an AVERAGE diameter of approximately 2 m. They play an important role in the blood coagulation process. There are usually 250,000–750,000 platelets in EVERY cubic mm of blood.

Right choice is (c) Polypropylene tubing

Explanation: Several other tubes are required to INTRODUCE reagents and to transport the specimen from one module to ANOTHER. There are five types of such tubings. They are of varying SIZES and are to be selected ACCORDING to the requirements. These are standard transmission tubing (Tygon), solvaflex tubing, acidflex tubing, polyethylene tubing and glass tubing.

Right choice is (B) 50 to 75 mm Hg

For explanation: During labour, the uterus muscle starts contractions of increasing INTENSITY in a bid to expel out the child. The intrauterine pressure can reach values of 150 MMHG or more during the expulsion period. However, a normal patient in SPONTANEOUS active labour will demonstrate UTERINE contractions occurring at intervals of three to five minutes, with a duration of 30 to 70 s and a peak intensity of 50 to 75 mmHg.

Right answer is (a) 660 nm

Best explanation: Pulse OXIMETRY is a particularly CONVENIENT noninvasive measurement method. Typically it UTILIZES a pair of small light-emitting diodes (LEDS) FACING a photodiode through a translucent part of the patient’s body, usually a fingertip or an earlobe. One LED is red, with a wavelength of 660 nm, and the other is infrared, 905, 910, or 940 nm.

The correct answer is (c) 6

The EXPLANATION is: The transmitting crystal emits a 40° divergent beam so that at 10 cm from the skin surface the beam covers an AREA of approximately 10 cm diameter. This construction ensures continuous recording of the foetal heart activity without the need to reposition the transducer which is otherwise necessitated due to normal foetal MOVEMENT. The transducer has a diameter of 6 cm and can be held in place either by a simple buckle or a stretch belt.

Right ANSWER is (b) Pulse Oximetry

To elaborate: Pulse oximetry is a non-invasive method allowing the monitoring of the SATURATION of a patient’s hemoglobin. A pulse oximeter shows the percentage of arterial hemoglobin in the oxyhemoglobin (HbO2) and hemoglobin (HB). These observations:

A = -logT = log I0/I =ɛDC.

The correct choice is (b) FALSE

The best I can explain: False, the labour-activity transducers are pressure transducers that drive circuits for obtaining an electrical indication of pressure by conventional means. The pressure channel on the recorder is provided with a positioning control. This is done because the baseline is affected by the static pressure on the transducer that results from the tension on the belt holding the transducer in PLACE. The control PERMITS the operator to position the baseline on the zero-level line of the recording chart.

Right answer is (C) pressure transducer

For explanation I would SAY: The labour-activity transducers are pressure transducers that drive CIRCUITS for obtaining an electrical indication of pressure by conventional means. The pressure channel on the recorder is provided with a positioning control. This is DONE because the BASELINE is affected by the static pressure on the transducer that results from the tension on the belt holding the transducer in place.

The correct choice is (c) Ultrasound technique

For EXPLANATION I would say: We can hear the signal through a loudspeaker with a scarce chance of failing to RECOGNIZE any BEAT, but a simple electronic circuit may FAIL to trigger from this signal. Still, the ultrasound Doppler shift method is more practical and easy to use during labour. It is currently the most reliable method for detecting the FHR pattern that is interpretable.

Correct answer is (c) 1 ml

The EXPLANATION: INSTRUMENTS BASED on optical technique TAKE about 30 s for completing the count. An ACCURACY of 2% is attainable. The instruments require about 1 ml of the blood sample.

Right option is (d) Phasing coils

The best I can explain: In order to ENSURE a proper sequencing for the PRESENTATION of results, a number of devices have been provided to make this adjustment an extremely simple operation. Phasing coils are used to PERMIT the CHANNELS to enter the colorimeter in the proper sequence.