• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Rapid ascent to high altitude (2500m or more) can result in the development in High Altitude Pulmonary Oedema (HAPE). Discuss the aetiology and the pathophysiology of HAPE.

Extracts from this document...

Introduction

Rapid ascent to high altitude (2500m or more) can result in the development in High Altitude Pulmonary Oedema (HAPE). Discuss the aetiology and the pathophysiology of HAPE.

In recent years mountain climbing and mounting trekking has grown in popularity, however there are certain dangers associated with high altitude (2500m or higher) pursuits. It has been known for centuries that there are risks of damaged health to humans by going to high altitudes; with the physiological effects of being at altitude being realised since the 19th century. It has also been known that these effects are as a result of inspiring less oxygen as there is a fall in barometric pressure with altitude (Sonna, 2002) (Figure 1).

(Figure 1). Shows the fall in barometric pressure and PO2 associated with a rise in  

                  altitude.

image00.png

(Lumb, 2000).

As seen from viewing figure 1, both the barometric pressure and inspired PO2 dramatically decrease with an increase in altitude. From sea level (0 m) to 3000m (the typical altitude HAPE develops at) there is a decrease from 760 mmHg to 520 mmHg for barometric pressure, a 140 mmHg / 18.5 % decrease. Inspired PO2 values decrease from 150 mmHg to 100 mmHg, a 50 mmHg / 33.3 % decrease. It is this decrease in oxygen inspiration that causes physiological problems associated with high altitudes.

There

...read more.

Middle

4.5

Rennie

Nepal

Maggiorini

Swiss Alps

3650

82

34

27

2.4

Basnyat

Gosaikkund

4300

228

68

-

4.8

Nepal

Cremona

Monte Rosa

4559

262

-

15

0.4

Italy

(Sonna, 2002).

As can be seen from figure 2 the number of people who contract AMS is high with a mean value of 49.5 % ± 14.6 %, however the number of people who then develop   HAPE is relatively low at 2.5 % ± 1.9 %.  

High altitude pulmonary oedema (HAPE) is a subject that has grown in interest in the past 15 years as more people are getting into situations where they may develop HAPE and better scientific techniques such radiographic images, which can specify between other pulmonary oedemas and HAPE (Gluecker et al., 1999) are allowing gradual understanding of the aetiology and pathophysiology of this condition.

The pulmonary circulation main function is to move a good supply of blood from the right ventricle to the alveolar capillaries (blood gas barrier) so gas exchange can occur (Cotes, 1993; West, 2000). This system is disrupted when HAPE occurs as the rise in pulmonary capillary pressure causing interstitial oedema, which disrupts the ventilatory perfusion ratio, the congestion caused by the oedema results in reduced lung compliance and maximum ventilation, hence many patients continually hyperventilate (Cotes, 1993; Maggiorini et al., 2001). Symptoms include those that are similar to AMS, dyspnea, chest congestion, nausea, tachycardia, fever, weakness, coughing, chest infections, sputum upbringing on coughing and

...read more.

Conclusion

Gluecker, T., Capasso, P., Schnyder, P., Gudinchet, F., Schaller, M., Revelly, J., Chiolero, R., Vock, P. and Wicky, S. (1999). Clinical and radiologic features of pulmonary edema. Radiographics, 19, 1507-1531. (Abstract).

Hultgren, H. N., Honigman, B., Theis, K. and  Nicholas, D. (1996). High-altitude pulmonary edema at a ski resort. Western Journal of Medicine, 164, 222-227.

Kumar, P. and Clark, M.  (1998). Clinical  Medicine 4th ed . London.: W. B. Saunders.

Lumb, A. B. (2000). Applied Respiratory Physiology 5th ed. Oxford.: Butterworth Heinemann.

Maggiorini, M., Mélot, C., Pierre, S., Pfeiffer, F., Greve, I., Sartori, C., Lepori, M., Hauser, M., Scherrer, U. and Naeije, R. (2001). High-altitude pulmonary edema is initially caused by an increase in capillary pressure. Circulation, 103, (16), 2078 - 2083.

McArdle, W. D., Katch, F. I., and Katch, V. L. (1996). Exercise Physiology: energy, nutrition and human performance 4th ed. Baltimore, MD.: London: Williams & Wilkins.

Roach, R. C., Houston, C. S., Honigman, B., Nicholas, R. A., Yaron, M., Grissom, C. K., Alexander, J. K. and Hultgren. (1995). How well do older people tolerate moderate altitude ? Western Journal of Medicine, 162, 32 - 36.

Scherrer, U., Vollenwider, L., Delabays, A., Savcic, M., Eichenberger, V. and Kleger, G-R. (1996). Inhaled nitric oxide for high altitude pulmonary edema. New England Journal of Medicine, 334, 624 – 629. (Abstract).

Sonna, L. A. (2002). Pulmonary oedema at moderately high altitudes. The Lancet, 359, (9303) 276 – 280.

Taylor, A. E., Rehder, K., Hyatt, R. E. and Parker, J. C. (1998). Clinical Respiratory Physiology. London.: W. B. Saunders.

West, J. B. (2000). Respiratory Physiology: The essentials 6th. Baltimore, MD.: London: Lippincott Williams & Wilkins.

...read more.

This student written piece of work is one of many that can be found in our GCSE Height and Weight of Pupils and other Mayfield High School investigations 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 GCSE Height and Weight of Pupils and other Mayfield High School investigations essays

  1. Statistics Mayfield High

    The results are most densely distributed at 4 on the x axis and 105 on the y axis. The SD for the Male IQ is 11.271 and 0.881 for Male KS2 results; which shows that the results are closely distributed.

  2. Mayfield High School

    I have now placed the equations of the line of best fit and the R� values of these scatter graphs into a table. Equation of line of best fit R� IQ/English Y=0.0829x - 4.404 0.8844 IQ/Maths Y=0.0384x + 0.2616 0.1972 IQ/Science Y=0.0548x - 1.4942 0.2793 IQ/Average KS2 Results Y=0.0587x -

  1. Investigation on the shape and size of limpets on a sheltered rocky shore called ...

    It's not really terrestrial nor truly marine. The upper shore is where the top of this zone gets covered by the sea for <1% of the year. The bottom of it for about 20% of the year. The middle shore is where the top gets covered for about 20% of the year.

  2. Mayfield High School Project

    but to make a proper comparison I will need to plot both sets of data on the same graph. Plotting two histograms on the same page would not give a very clear graph, which is why I feel by using a frequency polygon it will make the comparison a lot clearer.

  1. Mayfield High School

    This is because it is quick, easy and efficient to choose my samples from each year from a long list of 1183 students. In a random sample, every member of the population has an equal chance of being selected. Random samples need to be carefully selected using a variety of

  2. Mayfield High School

    I want to obtain a sample of size 30 from a population of 1183. I have chosen to use a sample size of 30 because it will have enough data to show any trend in the data but will be small enough to manipulate and analyse.

  1. &amp;quot;Medicine was a Battleground for the war between the sexes in the Greco-Roman World&amp;quot;. ...

    Throughout I shall make reference to sources ranging from Greek mythology, the Hippocratic Corpus and a variety of secondary literature, and it is to sources, communication and literature that I turn to first. Any analysis of the Greco-Roman world will always be skewed by the distinct bias of texts produced entirely (as far as we know)

  2. Starting to ski Skking can be a wonderful way to enjoy the outdoors in ...

    This is called the Snowplough Stop. Another way of progressing more moderately down a slope is to ski from side to side.

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