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as the manually inflated cuff of a sphygmomanometer. High and low reading which are based on the systolic and diastolic
pressure respectively is recorded through a quick series of read- ing on the pressure exerted on the switch. With a built in clock,
the time of reading can be stored for further analysis. Telemedi- cine technology grants much more than remote controlling and
periodic blood pressure monitoring. It will alert the medical team when certain procedures which are not suitable to be per-
formed on patients with special needs arise. For instance using a sphygmomanometer on a patient who is suffering from sickle
cell anemia is not recommended as excessive pressure applied to the patient can cause intravascular sickling which may lead to
tissue necrosis, intravascular thrombi and haemolysis. In order to avoid such consequences, checking the medical history of the
patient can be done electronically prior to performing any treatment to the patient. As we have discussed briefly on the
methods which technology can assist in the monitoring and measurement of blood pressure, we will proceed to the next vi-
tal sign which is the respiration rate.
4.1.4 Rate of Respiratory Normal Range: 12–24 breaths per minute
Respiratory rate is the most challenging aspect of measurement amid all the body vital signs because of its significant change
over a very short lapse of time. The respiratory rate is most likely intertwined with heart beat since the level of intensity of
activity would influence both parameters. Taking a deep breath might increase the duration of breath cycle and therefore cause
the reduction of respiratory rate. On the other hand, heart beat would be less affected. The breathing rate of a healthy adult is
12-24 times per minutes, which is much lower than heart rate.
115
Figure 4.7 Underwater Telemedicine applications
FONG et al 2011 The breath rate is based on the age of the person; usually a new-
born has more than 40 breathes per minute whereas a toddler has around 30 breaths. Compared to the three listed above, res-
piratory rate may give fewer significant information when ex- amining the health state of a person. However, respiratory rate
measurements can be utilized effectively for activities such as diving, in which the respiratory rate of a diver determines his or
her length of time staying submerged underwater. Figure 4.7 shows the list of equipment for divers. Here, the most important
device is button to seek for help. If used together with a beacon, the divers position can be located easily. At this section, we
will discuss about technology which measures the respiratory to provide a constantly updated estimate of the amount of oxygen
remaining before the diver must decompress and resurface. Be- sides that, the alert will automatically trigger to ask for help if
respiration abnormality is detected. Generally, respiratory rate is measured for patient who suffer from lung disease or patient
who take medication to suppress respiration. The respiratory monitoring system can also detect asthma symptoms such as
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bouts of breathlessness. Apart from asthma, severe conditions such as tachypnea, caused by conditions such as fever, conges-
tive heart failure and pneumonia which result in irregular in- crease of respiratory rate can also be detected. The breathing
rate is easy to count because it is rhythmic and slow. The respir- atory rate can be determined by counting the number of the in-
crease and decrease of the thorax. The thorax motion during breathing can be measured by putting a pressure-sensitive
switch attached to a counter inside a vest. The chest will expand when the diaphragm muscle contract and the chest cavity will
shrink when the diaphragm muscle relaxes. The switch counts the frequency of this repeated motion.
4.1.5 Oxygen Saturation in Blood Normal range:
ࡿࢇࡻ
: 95– 100,
ࡿࢇࡻ
: 90–95 mmHg
Blood oxygen saturation is the ability of the lungs to supply ox- ygen to the blood. In the blood oxygen is carried chemically by
the hemoglobin and it dissolve physically in plasma.
Figure 4.8 Partial pressure of oxygen in arterial blood
ࡿࢇࡻ
FONG et al 2011
117
Measurement is normally done to analyze the oxygenation and saturation of hemoglobin in the blood. There are a few variables
used such as partial pressure in mmHg of oxygen in arterial blood
ࡼࢇࡻ
, which refers to a technique to measure the arte-
rial percentage of blood. ࡿࢇࡻ
And ࡿࢇࡻ
refers to direct and indirect measurement of the percentage in blood oxygen satura-
tion level. The former is determined using pulse oximetry and the latter is measured using arterial blood gas sampling. Even
though, ࡿࢇࡻ
and ࡿࡻ
appear to be similar actually these two variables are different from one another. The reading that is ob-
tained by arterial blood gas sampling can be affected by condi- tions such as anticoagulant medications and thrombolytic.
These variables are linked to respiration as inhalation brings oxygen into the lungs and exhalation releases carbon dioxide
out from the lungs.
ࡼࢇࡻ
Refer to a measurement of gas which can be determined using polarographic oxygen electrode as
shown in Figure 4.8. Polarographic oxygen electrode contains a platinum cathode and a silver chloride anode in which generates
an electrical current; the electrical current is proportional to the oxygen. The blood sample must be isolated from the electrode
by a membrane to avoid protein deposition. The equipment must be kept in an oven that has a temperature analogous to the
human body temperature which is approximately 37
◦C. The membrane is should not contain any protein deposit that might
accumulate on the surface over time. Pulse oximetry is a non- invasive method of continuous arterial oxygen saturation moni-
toring. The pulse OX meter is a tiny portable device which par- amedics can carry to the site of an accident. It can measure the
arterial oxygen saturation
ࡿࢇࡻ
of a patient. According to the formulae, the maximum amount of oxygen that can be carried
by the blood is determined as:-
ࡿࢇࡻ
ൌ
ை
మ
ை
మೌೌ
ݔͳͲͲΨ
4.1
