• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9
  10. 10
  11. 11
  12. 12
  13. 13
  14. 14
  15. 15
  16. 16
  17. 17
  18. 18

Research Question (RQ) How does the position of the arm (cuff) in relation to the heart, affect the blood pressure[1] of non-diabetic, female, 16 year olds, in terms of Systolic Pressure[2] and Diastolic Pressure[3]?

Extracts from this document...


IB Biology Human Physiology - Circulatory System - Open Investigation Planning A Research Question (RQ) How does the position of the arm (cuff) in relation to the heart, affect the blood pressure1 of non-diabetic, female, 16 year olds, in terms of Systolic Pressure2 and Diastolic Pressure3? Hypothesis It is known that there are many factors that influence blood pressure and blood pressure readings one of which will be explored in this experiment - the affect of the position of the monitored extremity (cuff) in relation to the heart. 'Blood pressure readings may be influenced by body position because of variation in the vertical distance between heart and cuff level.' (CAVELAARS Marinel; et al. - 2000) It is hypothesised that blood pressure will increase as the position of the monitored arm moves from 'Below the Heart' to 'In Line With the Heart' to 'Above Heart' in a proportional manner. To investigate this, the systolic pressure and diastolic pressures (mmHg) will be measured when the monitored arm is in various positions. In line with this prediction, literature states that, 'When the blood pressure (BP) is measured, the arm should be at the level of the heart' (STEPHEN S.EHRLICH, M.D., - 2004) and that the values thus produced will be the true blood pressure values.' Therefore the blood pressure values calculated with the monitored arm 'In Line With the Heart' will be treated as the control values and the other values will be analysed in relation to this control as that is the advised method for blood pressure measurement. Past studies into pulse oxygenation (SpO2) have shows that, 'by merely changing the position of the monitored extremity, the SpO2 can change by up to six percent. In this study, the arm was raised 90 degrees from surpine and this resulted in a highly significant decrease in SpO2 with elevation of the monitored arm.'4 (Cooke, J., Johansen, J., 2000) ...read more.


110.0 91.0 Subject 10 1 101.0 61.0 102.0 71.0 123.0 86.0 2 142.0 93.0 86.0 61.0 143.0 76.0 3 145.0 62.0 157.0 106.0 159.0 104.0 Average: 122.8 74.2 123.7 76.5 133.7 89.8 Uncertainties: Pressure +/- 3mmHg For the following tables and graphs, the average systolic and diastolic pressure (mmHg) values for each of the three positions of the monitored arm have been grouped by these positions and the total average for each position been calculated. This was done so that the tables and graphs can really depict the total averages for the positions of the arm - and thus the resulting difference. Table 4: The Total Average Systolic (SYS) and Diastolic (DIA) Pressures (mmHg) for the respected positions of the monitored arm in relation to the heart grouped by pressure Test SYS (mmHg) DIA (mmHg) 1 (directly above head) 2 (at heart level) 3 (down by side) 1 (directly above head) 2 (at heart level) 3 (down by side) Average: 122.8 123.7 133.7 74.2 76.5 89.8 Uncertainties: Pressure +/- 3mmHg Calculations for Descriptive Statistics: Mean - the average of all data entries Median - the middle value when data entries are placed in rank order Variance - A measure of the spread of the values in a distribution. The larger the variance, the larger the distance of the individual cases from the group mean. 5 The formula says to take a score (X) and subtract the mean (�), then square this difference (X-�)2 and sum up all of these squared differences (?(X- �)2), and divide the sum by the number of scores(N).6 Standard Deviation - a frequently used measure of the variability (spread) in a set of data Standard Error - an error measurement (reliability of your data) The 95% Confidence Interval - used to calculate and reveal on average, 95 times out of 100, the limits which usually contain the true mean P(n - 1) ...read more.


- as is the correct way to monitor blood pressure - it produced the middle value; and that when the cuff is parallel to the body and resting by the side, it results in the highest blood pressure reading. It can be concluded from these results that to obtain accurate and consistent blood pressure readings, it is important to implement the proper arm position - with the monitored arm perpendicular to the body, with a slightly flexed elbow - to correctly determine blood pressure levels with a wrist pressure monitor. Error/Limitation Impact / Significance Improvements The experiment wasn't repeated an adequate amount of times so there wasn't enough data and the data may be inconsistent. There wasn't enough data and the data that was used, was inconsistent. I propose that this experiment be repeated 3 more times so that the data that is collected is more consistent. The CASCADE Blood Pressure Monitor kept coming up with an ERROR message. This resulted in the subject holding their arm (cuff) in a position for a longer period of time. Because they had to hold their arm in a position for longer, it may have affected their results more than the others and this would have resulted in the discrepancies and outliers. I propose that another electronic piece of equipment that is more reliable be used. An example of such a piece of equipment is the Pasco data logger - with heart rate monitors. Because the subject's got bored, annoyed and agitated with having to hold their arm in uncomfortable positions for a consistent period of time, they became distracted and began running around and not remaining in one position for the duration of the experiment. This may have affected the results as because they were moving - and moving quickly - their heart rate and subsequently their blood pressure would have increased. This would have resulted in incorrect data. I propose that next time this experiment is undertaken, the subjects are required to be in a seated as opposed to standing position for the duration of the experiment. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Biology section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related International Baccalaureate Biology essays

  1. Marked by a teacher

    Neurology and Behaviour. Focus question: Is there an increase in the perception and ...

    5 star(s)

    1 1 1 1 2 2 1 1 13 2 2 1 1 3 1 1 2 1 2 14 4 2 1 1 3 1 1 3 2 3 15 1 2 1 1 1 1 2 4 2 4 16 2 2 1 1 4 1 3 5

  2. To investigate how aerobic exercise affects the heart rate

    However, there were a few minor flaws. Firstly, due to time constraints, it was quite difficult to perform the experiment at exactly the same time of the day. Also, the experiment was based around the schedule of the test subject so the time the experiment was conducted isn't consistent.

  1. biology extended essay - How different diets: vegetarian, vegan and a meat centered diet ...

    Lacto vegetarian diet 2. Lacto-ovo vegetarian diet 3. Ovo vegetarian diet Lacto vegetarian diet This a vegetarian diet that avoids eating meat but does allow the consumption of diary products such as milk, butter, cheese, creame and yogurt etc. This diet does not however allow the consumption of eggs eventhough it is a diary product.

  2. Research Question: Does the duration of exercise have an increased effect on a persons ...

    The Time Watcher should count 60 seconds by watching the clock f. After 60seconds the Time Watcher should shout "Stop" g. Record each students heart rate 6. Record Heart Rate for 90 seconds of exercise a. Repeat steps 4a-4e replacing 45 seconds with 90 seconds.

  1. Biology lab- osmotic pressure

    0.19 ? (34 + 273) = 4.78 atmospheres 273 Evaluation The procedure of the investigation provides a reliable method for deducing the osmotic pressure at which plant cells are 50% plasmolysed in sucrose solution. The hypothesis that we had formulated has been verified through this experiment.

  2. What is the effect of different body positions i.e. lying down, sitting and standing ...

    * Lying down * Sitting up * Standing up Dependent: the blood pressure of the participants in each of the different positions * Diastolic (mmHG) * Systolic (mmHG) Control: the following variables were controlled: * Age of the participants (16 years)

  1. Lung Capacity Fitness Level

    The amount or air will be measured in decimetres cubed. The amount of air breathed (inspired / inhaled) in is given as a negative value on the GLX meter and on the other hand the amount of air breathed out (expired / exhaled) by participants are shown as positive values.

  2. Aim To investigate the effect of strenuous physical activities such as badminton and bodybuilding ...

    The result of the injection of blood into the arteries by the ventricles undergoing systole is the generation of blood pressure, the primary driving force for the flow of blood through the body Electrical charges occurring during the cardiac cycle can be monitored from the surface of the body in a recording called an electrocardiogram (ECG/EKG in short).

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work