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Correct option is (d) pulsatile

The explanation: Most of the absorbances are fixed and do not CHANGE with time. Even BLOOD in the capillaries and veins under steady state METABOLIC circumstances is constant in composition and FLOW, at least over short periods of time.Only the blood flow in the arteries and arterioles is pulsatile.

Right choice is (d) 6/min or 12/min

The best explanation: In ARRHYTHMIA monitoring INSTRUMENT, it gives alarm light signals WHENEVER the prematured or widened ECTOPIC beat exist up to the rate of 6/min or 12/min.It is ONE of the operating sequences of the arrhythmia monitoring instrument.

Right answer is (b) 2

To elaborate: PULSE OXIMETRY is based on the CONCEPT that ARTERIAL OXYGEN saturation determinations can be made using two wavelengths, provided the measurements are made on the pulsatile part of the waveform.

Right OPTION is (a) 5-10 min

Explanation: Maximum vasodilatation is achieved by KEEPING the ear warm. It takes about 5 or 10 min for the ear to BECOME fully dilated after the ear UNIT has been put up in place and the lamp turned on.

The correct option 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 choice is (c) TRANSMISSION

The explanation is: For discrete blood samples, a spectrophotometric measurement of oxygen SATURATION can be made by EITHER a transmission METHOD or a reflection method.

The correct option is (a) True

To ELABORATE: It is true. BLOOD is a poor conductor of electricity. This PRINCIPLE is used in Coulter counters to count the NUMBER of RBCs in the blood.

The correct answer is (b) high permeability to water

To explain I would SAY: The ideal membrane should possess high permeability to water, organic METABOLITES and ions, and the capability of retaining PLASMA proteins. The membrane should be of sufficient wet STRENGTH to resist tearing or bursting and non-toxic to blood and all BODY cells.

Right OPTION is (c) priming volume

For explanation: The volume of blood WITHIN the dialyzer is known as priming volume.It is DESIRABLE that this should be minimal. Priming volume of present day dialyzers ranges from 75 to 200 ml, depending on the membrane AREA geometry and operating conditions.

The correct OPTION is (b) REFLECTION Pulse Oximeter

The EXPLANATION: However, in comparison to transmission, the reflection pulse oximeter has POORER SIGNAL-to noiseratio. Mendelson et al (1988) utilized multiple photodiodes around the light source to enhance signal level.

The correct ANSWER is (d) Lamber-Bouguer, Beer’s and Beer-Lambert LAW

Easy explanation: Light passing through the ear or finger will be absorbed by skin PIGMENTS, TISSUE, cartilage, bone, arterial blood, venous blood. The absorbances are additive and obey the Beer-Lambert law. Beer-Lambert is COMBINATION of Lambert-Bouguer and Beer’s Law.

The correct option is (c) notch filters

The best I can explain: A notch filter is employed to suppress the hum NOISE generated by the POWER SUPPLY in the ECG CIRCUIT. CMRR of the order of 100–120 dB with 5 kW unbalance in the leads is a desirable feature of ECG machines. The instability of the baseline, originating from the changes of the contact impedance, DEMANDS the application of the automatic baseline stabilizing circuit.

Right option is (c) Rhythm labeling

For explanation I would say: Rhythm labeling is the final stage in arrhythmia ANALYSIS. It is based on defined sequences of QRS complexes. The analysis systems are heavily ORIENTED towards DETECTING ventricular arrhythmias, particularly single PVCS.

The correct ANSWER is (a) oxygen

The explanation: In clinical practice, the percentage of oxygen SATURATION in the BLOOD is of great IMPORTANCE. This saturation being a bio-constant is an indication of the performance of the most important cardio-respiratory functions. It is MAINTAINED at a fairly constant value to within a few percents in a healthy organism.

Right option is (c) 2.5

Easiest 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.

Correct answer is (a) True

Explanation: YES, maximum vasodilatation is achieved by keeping the EAR warm. It takes about 5 or 10 min for the ear to become fully dilated after the ear unit has been PUT up in place and the lamp TURNED on.

The correct ANSWER is (B) transmission

Easiest explanation: Ear oximeters usually make use of the transmission principle to measure ARTERIAL oxygen saturation. In this case, the pinna of the ear acts as a cuvette. BLOOD in the ear MUST be made similar to arterial blood in composition.

The CORRECT choice is (c) 5-6 L

To explain: In an average adult about 5-6 L of blood is present. 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 PERCENTAGE of cells in the blood is called the haematocrit value or PACKED cell volume (PCV).

Correct ANSWER is (c) Silicon diode

For explanation I would say: 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.

Right option is (B) Ear

Best explanation: Merrick and Hayes (1976) describe details of an ear oximeter which enables the measurement of OXYGEN saturation of the 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 CHOICE is (a) ratio (R) of pulse-added red absorbance at 660 nm to the pulse-added infrared absorbances at 940 nm

The EXPLANATION is: Oxygen saturation is estimated from the ratio (R) of pulse-added red absorbance at 660 nm to the pulse-added infrared absorbances at 940 nm.

Correct answer is (C) 8

To EXPLAIN I WOULD say: In brief, the technique involves measuring the optical transmittance of the ear at 8 wavelengths in the 650 to 1050 nm range. A 2.5 m LONG flexible fibre ear probe connects the patient to the instrument.

Correct answer is (a) True

The best I can explain: It is true. The sensitivity of an electrocardiograph is typically set at 10 mm/mV. For routine work, the paper recording SPEED is 25 mm/s. Amplitude MEASUREMENTS are MADE vertically in millivolts. Time measurements and heart RATE measurements are made horizontally on the electrocardiogram.

Right choice is (c) accuracy

For explanation: An accuracy of 1% or BETTER has been reported for the SATURATION range of above 80% for most TRANSMISSION type PULSE oximeters. Usually, the accuracy is less at LOWER saturation because of non-linear effects of absorption.

Right option is (a) Photodiodes

For explanation: However, in comparison to transmission, the reflection pulse oximeter has poorer signal-to NOISE ratio. Mendelson et al (1988) utilized MULTIPLE photodiodes around the light SOURCE to enhance signal LEVEL.

Correct CHOICE is (a) Cohen and Wadsworth

For explanation: Cohen and Wadsworth (1972) bring out the difficulties in the extraction of useful information from backscattered light INTENSITY from human tissue. There are vast variations of tissue construction and OPTICAL properties among VARIOUS subjects and in different LOCATIONS on the same subject.

Correct choice is (d) skin PIGMENTATION, thickness and tissue

To EXPLAIN I would say: The instrument can be empirically calibrated. Subject variability (skin pigmentation, thickness, tissue, sensor location, ETC.) has no SIGNIFICANT influence on the measurement.

Correct option is (B) 2

Easy EXPLANATION: This has two LEDs (light emitting diodes), one that transmits infrared light at a WAVELENGTH of APPROXIMATELY 940 NM and the other transmitting light at approximately 660 nm.

Correct choice is (a) True

Best explanation: PULSE oximetry is a technology used to measure the OXYGEN level in your BLOOD and your heart RATE. A finger pulse oximeter is equipped with technology to rapidly detect changes in your blood oxygen level.

Correct answer is (a) 5-10 %

For explanation: 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 percentage of cells in the blood is called the haematocrit value or PACKED cell volume (PCV).

The correct answer is (b) TWO steps

Easiest explanation: QRS detection is now almost universally performed digitally in a two-step PROCESS. The ECG is FIRST preprocessed to enhance the QRS complex while suppressing noise, artifact and non-QRS portions of the ECG. The output of the preprocessor stage is subjected to a decision RULE that confirms the detection of QRS if the processor output exceeds a threshold.

The CORRECT option is (B) 2

Easy explanation: The instrument BASICALLY depends on monitoring backscattered light from living tissue in two wavelengths. The backscattered light data is then USED for the in vivo determination of the blood’s relative oxygen saturation.

The correct choice is (c) laproscopic

The BEST I can EXPLAIN: The branch of medicine that deals with the provision and use of artificial devices such as splints and braces are orthotics.A modality-specific APPLIANCE that aids the PERFORMANCE of a function or movement by augmenting or assisting the residual capabilities of that function or movement. An orthopaedic brace is an ORTHOSIS.

The correct option is (d) Frequency domain analysis

The best I can explain: Ventricular fibrillation is USUALLY DETECTED by frequency domain analysis. The system is CHARACTERIZED as a narrow-band, low frequency signal with energy concentrated in a band AROUND 5-6 Hz. It can be distinguished from noise by appropriately designing band-pass FILTERS.

Correct choice is (a) in vitro

To explain I would say: When BLOOD is withdrawn from the subject under ANAEROBIC CONDITIONS and measurement for oxygen saturation is made at a later TIME in the laboratory, the procedure is referred to as in vitro OXIMETRY.