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The CORRECT answer is (C) 5”

Best explanation: Small cardioscopes USING 3” diameter cathode ray tubes are mounted on anaesthesia TROLLIES. These are called “Anaesthesia monitors”. These monitors are use by the anaesthetist for CONTINUOUS monitoring of the ECG of anaesthetized patients.

The CORRECT OPTION is (a) TRUE

To elaborate: True, Biofeedback instrumentation for the measurement of EMG, TEMPERATURE and pulse/heart rate as it is not different from other instruments used for the measurement of physiological variables. TRANSDUCERS and amplifiers are employed to measure the variable that is to be controlled by the feedback process.

Correct choice is (B) baseline value of skin resistance

For explanation: BSR (BASAL skin response) and GSR (GALVANIC skin response) is a measure of the AVERAGE activity of the sweat GLANDS and is a measure of the phasic activity (the high and low points) of these glands. BSR gives the baseline value of the skin resistance where as GSR is due to the activity of the sweat glands.

The correct choice is (b) two

Easiest explanation: The foetal heart rate is COMPUTED from the foetal ECG by appropriately SHAPING the foetal QRS WAVE. The FOETUS heart rate is approximately twice that of the NORMAL adult ranging approximately from 110 to 180 bpm. The main problem in processing the foetal heart signals is the poor SNR.

Correct choice is (b) 40-240 bpm

Easy explanation: The SUBSTITUTION logic REQUIRES a delay time to establish a missing foetal TRIGGER pulse. It is thus kept as 270 ms. The range of FHR measurement is limited to 40–240 bpm because of the substitution logic. Thereafter, the output of logic CIRCUITS goes to standard heart rate computing circuits.

Right choice is (a) 100 to 300 MV

Easy EXPLANATION: Foetal electrocardiogram is recorded by suitably placing the electrodes on the mother’s abdomen and recording the combined maternal and foetal ECG. The MAXIMUM amplitude of FECG (R wave) recorded during pregnancy is about 100 to 300 mV. This magnitude is much smaller than in the typical adult ECG which is about 1 mV in the standard LEAD connection.

Correct answer is (a) Foetal ECG with scalp electrode

To elaborate: The following METHODS are commonly employed in most of the cardiotocographic monitoring during labour: I) Indirect method: Abdominal foetal electrocardiogram, foetal phonocardiogram, ultrasound techniques (narrow beam and wide-angle transducer) II) Direct method: Foetal ECG with scalp electrode (spiral, CLIP or SUCTION electrode attached to the presenting part of the FOETUS).

The correct CHOICE is (c) Treadmill and Ergometer

The best I can EXPLAIN: Both the treadmill and ergometer can be used as stand-alone devices for testing PHYSICAL fitness. Advanced ergometers and treadmills can store and display activity data, transfer it to a PC and download PATIENT data from PC.

Right option is (b) False

Easiest explanation: False, FOETAL heart rate monitoring in the labour ward has generally been carried out on an INTERMITTENT BASIS. It has been traditional to listen to the foetal heart sounds at intervals of up to every 15 minutes. This is done by using the Pinard stethoscope.

The correct option is (d) 2.5 to 5 s

Explanation: Without a long persistence screen, ONE can only see a moving dot of light INSTEAD of a continuous trace. Typically for a 13-cm screen, total sweep time is USUALLY kept as 2.5 or 5 s. In this way, one can observe at least four heart beats in a single sweep PERIOD.

The correct choice is (c) Tocotonometer

To explain: Tocodynamometry is an indirect METHOD to measure uterine contraction in cardiotographic MONITORING during labour in which tocotonometer is USED to SENSE changes in uterine tension transmitted to abdominal skin surface.

Correct option is (c) 0-120 dB

To explain I would say: ABDOMINAL FECG processing CIRCUIT is used for COMPUTING foetal heart rate. After proper PLACEMENT of the electrodes, the signals are amplified in a preamplifier which PROVIDES a very high input impedance (100 MW) and high sensitivity and good common mode rejection ratio (up to 120 dB).

The correct option is (c) ECG

To ELABORATE: A Cardiac monitor is specifically useful for monitoring patients with cardiac PROBLEMS and the SPECIAL areas in the hospitals where they are generally used are known as cardiac care UNITS or coronary care units (CCU). These instruments are also called ‘Cardioscopes’ and comprise of disposable type pregelled electrodes to pick up ECG signal. AMPLIFIER and a cathode ray tube (CRT) for the amplification and display the ECG which enable direct observation of the ECG waveform.

The correct option is (a) True

Easiest explanation: ‘Cardioscopes’ and comprise of disposable type pregelled electrodes to pick up ECG SIGNAL. Amplifier and a cathode RAY tube (CRT) for the amplification and DISPLAY the ECG which enable direct observation of the ECG waveform.An ALARM system to produce signal in the event of abnormalities occurring in the heart rate.

The correct option is (d) 4

Best explanation: WITHOUT a long persistence screen, one can only see a moving dot of light instead of a CONTINUOUS trace. Typically for a 13-cm screen, total SWEEP TIME is usually kept as 2.5 or 5 s. In this way, one can OBSERVE at least four heart beats in a single sweep period.

Correct choice is (a) True

The explanation is: Clinical trials have shown that the AECG technique is usually effective in most CASES except in those rare cases where the amniotic fluid fails to PROVIDE adequate electrical coupling from foetus to mother. However, during labour, the uterine and abdominal wall electromyogram signals tend to obliterate the FECG signal, MAKING FHR COUNTING quite difficult. At present, the abdominal FECG, therefore, does not seem to offer a practical reliable means of FHR monitoring during labour and delivery.

The correct option is (c) 160 sec

For explanation: At an interval of 3 minutes the Bruce Protocol uses simultaneous increments in both speed and treadmill GRADE. Typically during a Bruce Protocol, Heart Rate and RATING of Perceived Exertion are taken every MINUTE and BLOOD Pressure is taken at the end of each stage (every three minutes).

Right answer is (a) palms of hand

To explain: BSR gives the BASELINE VALUE of the skin resistance where as GSR is due to the ACTIVITY of the sweat glands. The GSR is measured most conveniently at the palms of the hand, where the body has the highest concentration of sweat glands. The measurement is made using a dc current SOURCE.

The CORRECT answer is (a) 150 mmHg

For explanation I would say: During labour, the uterus MUSCLE starts contraction 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 answer is (C) Power Line Hum

Best explanation: A sizable common-mode signal manages to PASS through the input amplifier, a circumstance to be expected whenever electrodes spaced a few CENTIMETRES apart are ATTACHED to the human body in a hospital environment. Power line hum is responsible for most of the common-mode interfering signal. This is SUPPRESSED by a notch filter following the input amplifier.

Correct option is (c) 1-2 cm / min

Explanation: Normally, accuracy of measurement of foetal heart RATE may be 2-3% for classification for responses. Sensitivity of 20 BPM /cm of the recording chart allows adequate reading of the recorder FHR. Labour ACTIVITY and FHR traces are usually recorded simultaneously on the same time SCALE. Chart speed of 1-2 cm/min is adequate to provide sufficient resolution of the stimulus-response relationship.

Right choice is (d) Cathode ray tube

Easy explanation: ‘Cardioscopes’ and comprise of disposable type pregelled electrodes to pick up ECG SIGNAL. Amplifier and a cathode ray tube (CRT) for the AMPLIFICATION and display the ECG which ENABLE direct observation of the ECG waveform.

Right answer is (c) Cardiac Monitor

Easiest explanation: A Cardiac monitor is specifically useful for MONITORING patients with cardiac PROBLEMS and the special areas in the hospitals where they are generally used are known as cardiac care units or coronary care units (CCU). These INSTRUMENTS are also CALLED ‘Cardioscopes’.

Correct option is (b) Feedback

To elaborate: Feedback is a common engineering term and refers to its FUNCTION to control a process. When this concept is applied to biological processes within the BODY, it is known as biofeedback. Biofeedback is a means for gaining control of the body processes to create a specially required PSYCHOLOGICAL STATE so as to increase relaxation, relieve pain and develop HEALTHIER and more comfortable life patterns.

Correct answer is (b) HEART RATE

The best I can explain: The most important physiological parameters monitored in the intensive care unit are the heart rate and the morphology or shape of the electrical waveform produced by the heart. This is done to observe the presence of arrhythmias or to detect changes in the heart rate that MIGHT be indicative of a SERIOUS CONDITION.

The correct answer is (d) Foetal ECG with scalp electrode

The best EXPLANATION: Abdominal foetal electrocardiogram, foetal phonocardiogram and Ultrasound TECHNIQUE are indirect methods of measuring foetal heart rate where as Foetal ECG with scalp electrode is a direct method as in it spiral, clip or SUCTION electrode is ATTACHED to the presenting PART of foetus.

The correct choice is (b) Stress test ELECTROCARDIOGRAPHY

The explanation is: Stress test or EXERCISE electrocardiography is used when the diagnosis of coronary arterial DISEASE is suspected or to determine the physical performance characteristics of a cardiac patient. The test involves the recording of the electrocardiogram during DYNAMIC or occasionally isometric exercise.

Right option is (b) FECG

Explanation: Abdominal FECG processing CIRCUIT is used for computing foetal heart RATE. After proper placement of the electrodes, the SIGNALS are amplified in a preamplifier which PROVIDES a very high input impedance (100 MW) and high SENSITIVITY and good common mode rejection ratio (up to 120 dB).

Correct answer is (b) 0.4 to 5 MHZ

The explanation is: Electrosurgery machines generate RF signals within a range of 0.4 to 5 MHz with peak-to-peak amplitudes of 100 to 1000 V, pulse modulated at rates from 1.5 to 25 kHz for coagulating or 120 Hz for cutting. Cardiac monitors are often used in OPERATION THEATRES, where the RF is applied through a pointed scalpel at the point of incision and the return path for the current is through a WIDE area electrode on the opposite side of the patient’s body.

Right answer is (b) 3 to 5

Explanation: Silver-silver electrodes are used to measure and RECORD the BSR and GSR. The BSR output is connected to an RC network with a time constant of 3 to 5 SECONDS which enables the measurement of GSR as a CHANGE of the SKIN resistance.

Correct option is (a) True

Explanation: True, BIOFEEDBACK training is an educational process for learning specialized mind/body skills as through practice, ONE learns to recognize physiological responses and to control them RATHER than having them control us. The objective of biofeedback training is to gain self-regulatory skills which help to ADJUST the activity in various systems to optimal levels.

Right option is (a) 1 mV

Easiest explanation: Foetal electrocardiogram is RECORDED by suitably placing the ELECTRODES on the MOTHER’s abdomen and recording the combined maternal and foetal ECG. The maximum amplitude of FECG (R wave) recorded during pregnancy is about 100 to 300 mV. This magnitude is much SMALLER than in the typical adult ECG which is about 1 mV in the standard lead connection.

The correct CHOICE is (d) 270 ms

The explanation: The substitution logic requires a delay TIME to establish a missing foetal trigger pulse. On the one hand, this delay has to be longer than the maximum permissible change in heart period (14 BPM change from 50–64 bpm = 262 ms) and on the other hand, it has to be shorter than the shortest period DURATION (216 bpm = 285.7 ms). It is thus KEPT as 270 ms.

The correct answer is (d) 50-210 bpm

The best 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.

Correct ANSWER is (d) 3.3 miles/hour

To elaborate: In the Balke-Ware Protocol, it uses a constant SPEED of 3.3 miles/hour (5.3 km/hour), with progressive INCREMENTS in the load EVERY 2 minutes. This is achieved by increasing the grade or incline of the motor-driven treadmill.

Correct answer is (c) RAM

The explanation: Two basic types of storage devices are USED to store DIGITAL information in memory MONITORS: shift REGISTERS and random access memories. Both of them are equally good for this application. The other important component of memory monitors is the analog-to-digital CONVERTER.

The correct option is (d) foetus

To explain I would say: The obstetrician is FACED with the problem of having very few parameters available on which to base a diagnosis of foetal well-being or distress. In most cases, the condition of the foetus is assessed by studying the blood FLOW in the foetal heart and its heart RATE. The foetal heart rate (FHR) yields IMPORTANT information about the status of the foetus, and therefore, has become a widely STUDIED parameter in maternity cases.

Right option is (a) activity of SWEAT glands

Explanation: BSR (basal SKIN response) and GSR (galvanic skin response) is a MEASURE of the average activity of the sweat glands and is a measure of the PHASIC activity (the HIGH and low points) of these glands. BSR gives the baseline value of the skin resistance where as GSR is due to the activity of the sweat glands.

The CORRECT option is (c) GSR

The BEST I can explain: Electrodermal activity is measured in TWO ways: BSR (basal skin response) and GSR (galvanic skin response) is a measure of the average activity of the sweat glands and is a measure of the phasic activity (the high and LOW POINTS) of these glands.

Correct OPTION is (d) Band Pass Filter

The best explanation: The signal path then splits into two channels: the maternal ECG CHANNEL or Mchannel and the foetal or F channel. Since the frequency SPECTRUM of the foetal ECG differs somewhat from the maternal ECG, some initial signal separation is achieved by using the APPROPRIATE bandpass filtering in each channel.

The correct answer is (d) 20

For explanation I would say: Cardiotocographs are designed to measure and record FOETAL heart rate on a beat-to-beat basis RATHER than on an average basis. Normally, accuracy of measurement MAY be 2–3% for the classification of responses. The sensitivity of 20 bpm/cm of the recording chart ALLOWS adequate reading of the recorded FHR.

The correct choice is (b) Cardiotocograph

To explain: The instrument which carries out a CONTINUOUS and simultaneous recording of the instantaneous foetal heart rate and labour activity is called cardiotocograph. In ADDITION to detecting long-term bradycardia or TACHYCARDIA, this instrument helps in the evaluation of foetal heart rate response of the undisturbed circulatory SYSTEM and response stimulated by uterine contractions.

Right choice is (C) 20 BPM / cm

To explain: Normally, an accuracy of measurement of foetal heart rate may be 2-3% for classification for responses. SENSITIVITY of 20 bpm /cm of the recording chart allows adequate reading of the RECORDER FHR. Labour activity and FHR traces are usually recorded simultaneously on the same time SCALE.

The CORRECT answer is (b) 0.67 Hz

The explanation is: To ensure that the ST SEGMENT can be measured accurately, the INCOMING ECG signals must have a low-end BANDWIDTH of 0.05 Hz. A special ST filter with a higher low-end bandwidth of 0.67 Hz is used to further remove unwanted baseline NOISE.

The correct CHOICE is (b) Isoelectric baseline

The explanation is: The current standard for DETERMINING the ST SEGMENT measurement is by measuring the voltage difference between the value at a POINT 60-80 ms after the J point and the isoelectric baseline. The isoelectric baseline is either between the P and Q waves (the P-R interval) or in front of the P-wave (the T-P interval).

The correct option is (d) 30

The explanation: The F CHANNEL has a 30 ms PULSE generator that is triggered by the foetal ECG. It is inhibited, however, by the blanking pulse from the M channel, so it will not GENERATE a pulse in response to the maternal ECG SIGNAL feeding through to the F channel.

Correct answer is (c) 0-100 mmHg

To explain: 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 while the other channel is used for recording UTERINE contractions calibrated 0-100 mmHg. The record is printed on thermo-sensitive z-fold paper using a high-resolution thermal MATRIX printer.