Download presentation
Presentation is loading. Please wait.
Published byRegina Garrett Modified over 9 years ago
1
Notes: Maintaining Life Maintaining Boundaries Movement Responsiveness Digestion Metabolism Excretion Reproduction Growth How do systems work together to promote these functions?
2
Notes: Maintaining Life Maintaining Boundaries Movement Responsiveness Digestion Metabolism Excretion Reproduction Growth How do systems work together to promote these functions?
3
Our First Example: The Death Zone What is hypoxia? What are the symptoms? How can this been seen as a positive feedbackmechanism? How does oxygen debt affect the brain? What makes Everest “Everest”? Why does your probability to make mental errorsincrease? Why does heart rate increase at altitude? What is this called? What are the affects of decreased oxygen to the brain? Does this cause brain damage? How is this studied? What are some symptoms of oxygen deprivation? What is Acute Mountain Sickness? What are its initial symptoms? What happens as it progresses? Where else might this happen? Why do climbers return to base camp before ascending further? What is high altitude pulmonary edema (H.A.P.E.)? How does it cause death? Why aren’t bodies removed from Everest? Why do bones remain after other tissues are eliminated? Why is the area above 27,000 ft. called the “death zone”? What happens when your resting heart rate matches your maximum heart rate? What are some specific dangers/emergency situations that may occur under these circumstances? Will David ever reach the summit of Everest Again ?
4
Gamow Bag
6
Not so elite
7
Next…
8
Survival Needs 1.Constant atmospheric pressure 2.Homeostasis
12
What went wrong? How does diving work?
14
Scuba
15
Jacques Cousteau
16
Boyle’s Law Boyle’s Law: The absolute pressure exerted by a given mass of an ideal gas is inversely proportional to the volume it occupies if the temperature and amount of gas remain unchanged within a closed system. Boyle's law describes how the pressure of a gas tends to decrease as the volume of a gas increases. The pressure of the gas also increases as the volume decreases
20
Rebreather
22
Nitrogen in the blood The bends
23
Nitrogen Narcosis “Narcing” Nitrogen narcosis or inert gas narcosis is a reversible alteration in consciousness producing a state similar to alcohol intoxication in Scuba divers at depths beyond 30m. Jacques Cousteau famously described it as the "rapture of the deep". Its precise mechanism is not well understood, but it appears to be a direct effect of high nitrogen pressure on nerve transmission. While it was first observed with nitrogen (in air), other gases including argon and hydrogen also cause very similar effects under high enough pressure. Xenon is actually a usable anaesthetic at atmospheric pressure, though it is too expensive to be used in practice. The onset is hard to recognize, its severity is unpredictable, and it can kill, from its own toxic effect or due to the resulting illogical behavior. However the cure for nitrogen narcosis is a simple one, as effects disappear upon ascending to shallower waters
24
CO 2 retention CO 2 retention is a pathophysiological process in which too little carbon dioxide is removed from the blood by the lungs. The end result is hypercarbia, an elevated level of carbon dioxide dissolved in the bloodstream. Various diseases may lead to this state; disturbed gas exchange may lead to impaired excretion of the gas. In addition, breathing air with a high carbon dioxide concentration may also lead to hypercarbia. The principal result of the increased amount of dissolved CO 2 is acidosis (respiratory acidosis when caused by impaired lung function); other effects include tachycardia (rapid heart rate) seizures, coma, respiratory arrest and death.
25
In diving CO 2 retention with its attendant dangers of death from convulsions and hypoxia (low oxygen level) is primarily of concern to the scuba diver due to "skip breathing". Other sources of CO 2 retention are breath-hold diving, breathing in a sealed environment, faulty regulator, exercise at extreme depth and using contaminated air. Symptoms include rapid respiration in 4-6%, rapid pulse rate, shortness of breath in 7-10% and convulsions and unconsciousness in 11-20%. The CO 2 level in the blood is unchanged by the ambient pressure (i.e., the depth) per se, since the partial pressure of carbon dioxide in a scuba diver's blood is a function only of metabolism and the rate and depth of breathing - the same factors that determine blood CO 2 concentration on land.
26
While Diving… All of the CO 2 developed during breathing underwater is exhaled in the bubbles from scuba apparatus and does not increase with depth as do other gases, such as nitrogen, oxygen, carbon monoxide and hydrocarbons. Abnormal carbon dioxide accumulation in the blood can occur from too high a level of metabolism (such as from exercise at depth) and/or inadequate breathing (usually not breathing deep enough or skip breathing). The medical term for high carbon dioxide in the blood is hypercapnia; when the level is high enough it can cause "CO 2 toxicity," which can lead to shortness of breath, headache, confusion and drowning (depending on severity).
27
Elevated CO 2 levels Elevated CO 2 levels play a significant role in oxygen toxicity and in nitrogen narcosis. The acceptable CO 2 level for diving operations is 1.5% surface equivalent (10.5 mmHg); the acceptable level for hyperbaric oxygen therapy operations is one that allows a vent schedule of 4scfm/person displacement
28
Rebreathers With the increased usage of rebreather diving, mainly by the military-but recently by more and more civilian divers, there is the possibility of hypercarbia (high CO 2 levels), among other medical considerations.
29
Further… What is the danger of breathing so rapid and shallow at these depths/altitudes? Why was Don Shirley so interested in mimicking Dave Shaw’s breathing? What does he mean when he says “I actually died with Dave”. Why was the experiment with David Carter similar? How are these experiences the same, how are they different?
31
Homeostasis 1.Negative Feedback Mechanisms 2.Positive Feedback Mechanisms
32
Feedback loops Negative feedback loop: monitors the environment, responds to changes, then shuts itself off. (self –regulated) -constantly monitors -responds to everyday changes Positive feedback loop: responds to traumatic, potentially catastrophic events. -cascade effect -does not shut itself off
33
NFM: Body Temp
34
Hypothalamus: Temperature Regulation Center
35
NFM: Body Temp
36
Negative Feedback Mechanism Ex: Blood Sugar Regulation
37
Negative Feedback Mechanism: Blood sugar regulation
38
Negative Feedback Mechanism
39
Positive Feedback Mechanism: Bleeding Ex: Blood Clotting
40
Positive Feedback mechanism: Childbirth
41
How breathing Works: Breathing as a feedback mechanism
42
How is breathing controlled? http://www.nhlbi.nih.gov/health/health- topics/topics/hlw/controls
43
Shark drawings
44
Cuts, Cavities, and Directions 1. Intro to Anatomical/Directional Terminology 2. Creepy Guy Lab 3. Read pp. 14-21 and answer questions 1-18
45
Stayin’ Alive
46
Survival Need: Constant and moderate atmospheric pressure How does the body stay alive in normal at situations? How does it react when pushed to and beyond extremes?
47
Notes: Maintaining Life Maintaining Boundaries Movement Responsiveness Digestion Metabolism Excretion Reproduction Growth How do systems work together to promote these functions?
48
Notes: Maintaining Life Maintaining Boundaries Movement Responsiveness Digestion Metabolism Excretion Reproduction Growth How do systems work together to promote these functions?
49
Our First Example: The Death Zone What is hypoxia? What are the symptoms? How can this been seen as a positive feedbackmechanism? How does oxygen debt affect the brain? What makes Everest “Everest”? Why does your probability to make mental errorsincrease? Why does heart rate increase at altitude? What is this called? What are the affects of decreased oxygen to the brain? Does this cause brain damage? How is this studied? What are some symptoms of oxygen deprivation? What is Acute Mountain Sickness? What are its initial symptoms? What happens as it progresses? Where else might this happen? Why do climbers return to base camp before ascending further? What is high altitude pulmonary edema (H.A.P.E.)? How does it cause death? Why aren’t bodies removed from Everest? Why do bones remain after other tissues are eliminated? Why is the area above 27,000 ft. called the “death zone”? What happens when your resting heart rate matches your maximum heart rate? What are some specific dangers/emergency situations that may occur under these circumstances? Will David ever reach the summit of Everest Again ?
50
Next…
54
What went wrong? How does diving work?
56
Scuba
57
Jacques Cousteau
58
Rebreather
60
Boyle’s Law
63
Deep Trouble What is the name of the cave, and where is it? Who is Dave Shaw and what happened to him? How (Be Specific)? What are the dangers of deep-water diving? Why is it especially dangerous to combine extreme depth with demanding work? What was not anticipated before the dive? How did this affect the dive? What is the danger of having too much nitrogen in the blood? How do the body’s feedback mechanisms work this out? What is the danger of having too much helium in the blood? How do the body’s feedback mechanisms work this out? What are decompression stops? What are recompression chambers (hyperbaric)? How do they work?
64
Further… What is the danger of breathing so rapid and shallow at these depths/altitudes? Why was Don Shirley so interested in mimicking Dave Shaw’s breathing? What does he mean when he says “I actually died with Dave”. Why was the experiment with David Carter similar? How are these experiences the same, how are they different?
65
Nitrogen Narcosis “Narcing” Nitrogen narcosis or inert gas narcosis is a reversible alteration in consciousness producing a state similar to alcohol intoxication in Scuba divers at depths beyond 30m. Jacques Cousteau famously described it as the "rapture of the deep". Its precise mechanism is not well understood, but it appears to be a direct effect of high nitrogen pressure on nerve transmission. While it was first observed with nitrogen (in air), other gases including argon and hydrogen also cause very similar effects under high enough pressure. Xenon is actually a usable anaesthetic at atmospheric pressure, though it is too expensive to be used in practice. The onset is hard to recognize, its severity is unpredictable, and it can kill, from its own toxic effect or due to the resulting illogical behavior. However the cure for nitrogen narcosis is a simple one, as effects disappear upon ascending to shallower waters
66
CO 2 retention CO 2 retention is a pathophysiological process in which too little carbon dioxide is removed from the blood by the lungs. The end result is hypercarbia, an elevated level of carbon dioxide dissolved in the bloodstream. Various diseases may lead to this state; disturbed gas exchange may lead to impaired excretion of the gas. In addition, breathing air with a high carbon dioxide concentration may also lead to hypercarbia. The principal result of the increased amount of dissolved CO 2 is acidosis (respiratory acidosis when caused by impaired lung function); other effects include tachycardia (rapid heart rate) seizures, coma, respiratory arrest and death.
67
In diving CO 2 retention with its attendant dangers of death from convulsions and hypoxia (low oxygen level) is primarily of concern to the scuba diver due to "skip breathing". Other sources of CO 2 retention are breath-hold diving, breathing in a sealed environment, faulty regulator, exercise at extreme depth and using contaminated air. Symptoms include rapid respiration in 4-6%, rapid pulse rate, shortness of breath in 7-10% and convulsions and unconsciousness in 11-20%. The CO 2 level in the blood is unchanged by the ambient pressure (i.e., the depth) per se, since the partial pressure of carbon dioxide in a scuba diver's blood is a function only of metabolism and the rate and depth of breathing - the same factors that determine blood CO 2 concentration on land.
68
While Diving… All of the CO 2 developed during breathing underwater is exhaled in the bubbles from scuba apparatus and does not increase with depth as do other gases, such as nitrogen, oxygen, carbon monoxide and hydrocarbons. Abnormal carbon dioxide accumulation in the blood can occur from too high a level of metabolism (such as from exercise at depth) and/or inadequate breathing (usually not breathing deep enough or skip breathing). The medical term for high carbon dioxide in the blood is hypercapnia; when the level is high enough it can cause "CO 2 toxicity," which can lead to shortness of breath, headache, confusion and drowning (depending on severity).
69
Elevated CO 2 levels Elevated CO 2 levels play a significant role in oxygen toxicity and in nitrogen narcosis. The acceptable CO 2 level for diving operations is 1.5% surface equivalent (10.5 mmHg); the acceptable level for hyperbaric oxygen therapy operations is one that allows a vent schedule of 4scfm/person displacement
70
Rebreathers With the increased usage of rebreather diving, mainly by the military-but recently by more and more civilian divers, there is the possibility of hypercarbia (high CO 2 levels), among other medical considerations.
71
Raising the Dead Positive and negative feedback mechanisms Raising the Dead Good idea? Anatomical Planes and Terminology
72
Sound Familiar? Signs and symptoms that need to be observed are hyperventilation, shortness of breath and tachycardia (rapid heart beat), headache and excessive sweating, mental impairment and finally, unconsciousness. hyperventilationtachycardiasweating
73
What killed Dave Shaw? According to Nuno Gomes, who understands why Shaw had trouble reacting to a body that was suddenly floating instead of anchored. “You don’t think of a new plan while you’re down there. It doesn’t work. Your mind is clouded.
74
What negative feedback mechanisms was enacted that day? Shaw passed out due to toxic levels of CO 2
75
Response: “Today, extreme divers are far exceeding any reasonable physiology capabilities”
76
Is this type if diving responsible?
77
Is any of this a good idea?
78
What are some other dangers that divers face?
79
Hyperbaric medicine Hyperbaric medicine is a corollary field associated with diving, since recompression in a hyperbaric chamber is used as a treatment for two of the most significant diving related illnesses, decompression illness and arterial gas embolism
80
Happy Wednesday Quiz 1.What is a negative feedback mechanism? Please give an example. 2.What is a positive feedback mechanism? Please give an example.
81
Is any of this a good idea?
83
Reminder: Human Hibernation? Read pp. 8-13 Then Read Article: “Suspended Animation” Homework: Answer the question: Is induced hibernation a useful technology/process to pursue? Or What is the future of induced hibernation?
84
Homeostatic Control Mechanisms Negative feedback mechanisms Positive feedback mechanisms
85
Homeostatic Control Mechanisms Negative Feedback mechanism
86
Homeostatic Control Mechanisms Positive Feedback mechanism
87
Raising the Dead Positive and negative feedback mechanisms Raising the Dead Good idea? Anatomical Planes and Terminology
91
Deep Trouble What is the name of the cave, and where is it? Who is Dave Shaw and what happened to him? How (Be Specific)? What are the dangers of deep-water diving? Why is it especially dangerous to combine extreme depth with demanding work? What was not anticipated before the dive? How did this affect the dive? What is the danger of having too much nitrogen in the blood? How do the body’s feedback mechanisms work this out? What is the danger of having too much helium in the blood? How do the body’s feedback mechanisms work this out? What are decompression stops? What are recompression chambers (hyperbaric)? How do they work?
92
Further… What is the danger of breathing so rapid and shallow at these depths/altitudes? Why was Don Shirley so interested in mimicking Dave Shaw’s breathing? What does he mean when he says “I actually died with Dave”. Why was the experiment with David Carter similar? How are these experiences the same, how are they different?
93
Could Dave Shaw have lived if he had people there? Why couldn’t anybody help him?
94
They are both practical examples of gas laws studied in chemistry.
95
Nitrogen Narcosis “Narcing” Nitrogen narcosis or inert gas narcosis is a reversible alteration in consciousness producing a state similar to alcohol intoxication in Scuba divers at depths beyond 30m. Jacques Cousteau famously described it as the "rapture of the deep". Its precise mechanism is not well understood, but it appears to be a direct effect of high nitrogen pressure on nerve transmission. While it was first observed with nitrogen (in air), other gases including argon and hydrogen also cause very similar effects under high enough pressure. Xenon is actually a usable anaesthetic at atmospheric pressure, though it is too expensive to be used in practice. The onset is hard to recognize, its severity is unpredictable, and it can kill, from its own toxic effect or due to the resulting illogical behavior. However the cure for nitrogen narcosis is a simple one, as effects disappear upon ascending to shallower waters
96
CO 2 retention CO 2 retention is a pathophysiological process in which too little carbon dioxide is removed from the blood by the lungs. The end result is hypercarbia, an elevated level of carbon dioxide dissolved in the bloodstream. Various diseases may lead to this state; disturbed gas exchange may lead to impaired excretion of the gas. In addition, breathing air with a high carbon dioxide concentration may also lead to hypercarbia. The principal result of the increased amount of dissolved CO 2 is acidosis (respiratory acidosis when caused by impaired lung function); other effects include tachycardia (rapid heart rate) seizures, coma, respiratory arrest and death.
97
In diving CO 2 retention with its attendant dangers of death from convulsions and hypoxia (low oxygen level) is primarily of concern to the scuba diver due to "skip breathing". Other sources of CO 2 retention are breath-hold diving, breathing in a sealed environment, faulty regulator, exercise at extreme depth and using contaminated air. Symptoms include rapid respiration in 4-6%, rapid pulse rate, shortness of breath in 7-10% and convulsions and unconsciousness in 11-20%. The CO 2 level in the blood is unchanged by the ambient pressure (i.e., the depth) per se, since the partial pressure of carbon dioxide in a scuba diver's blood is a function only of metabolism and the rate and depth of breathing - the same factors that determine blood CO 2 concentration on land.
98
While Diving… All of the CO 2 developed during breathing underwater is exhaled in the bubbles from scuba apparatus and does not increase with depth as do other gases, such as nitrogen, oxygen, carbon monoxide and hydrocarbons. Abnormal carbon dioxide accumulation in the blood can occur from too high a level of metabolism (such as from exercise at depth) and/or inadequate breathing (usually not breathing deep enough or skip breathing). The medical term for high carbon dioxide in the blood is hypercapnia; when the level is high enough it can cause "CO 2 toxicity," which can lead to shortness of breath, headache, confusion and drowning (depending on severity).
99
Elevated CO 2 levels Elevated CO 2 levels play a significant role in oxygen toxicity and in nitrogen narcosis. The acceptable CO 2 level for diving operations is 1.5% surface equivalent (10.5 mmHg); the acceptable level for hyperbaric oxygen therapy operations is one that allows a vent schedule of 4scfm/person displacement
100
Rebreathers With the increased usage of rebreather diving, mainly by the military-but recently by more and more civilian divers, there is the possibility of hypercarbia (high CO 2 levels), among other medical considerations.
101
Sound Familiar? Signs and symptoms that need to be observed are hyperventilation, shortness of breath and tachycardia (rapid heart beat), headache and excessive sweating, mental impairment and finally, unconsciousness. hyperventilationtachycardiasweating
102
What killed Dave Shaw? According to Nuno Gomes, who understands why Shaw had trouble reacting to a body that was suddenly floating instead of anchored. “You don’t think of a new plan while you’re down there. It doesn’t work. Your mind is clouded.
103
What negative feedback mechanisms was enacted that day? Shaw passed out due to toxic levels of CO 2
104
Response: “Today, extreme divers are far exceeding any reasonable physiology capabilities”
105
Is this type if diving responsible?
106
Is any of this a good idea?
107
What are some other dangers that divers face?
108
Hyperbaric medicine Hyperbaric medicine is a corollary field associated with diving, since recompression in a hyperbaric chamber is used as a treatment for two of the most significant diving related illnesses, decompression illness and arterial gas embolism
109
Happy Wednesday Quiz 1.What is a negative feedback mechanism? Please give an example. 2.What is a positive feedback mechanism? Please give an example.
110
Human Hibernation Assignment Read pp. 8-13 Then Read Article: “Suspended Animation” Homework: Answer the question is a single page-single spaced essay (or 2 pages double spaced) Is induced hibernation a useful technology/process to pursue? Or What is the future of induced hibernation?
112
Due By Tuesday Think: Could induced hibernation change the way we save lives involving traumatic injuries? Ho could induced hibernation advance space travel and colonization?
114
Our First Example: The Death Zone What is hypoxia? What are the symptoms? How can this been seen as a positive feedbackmechanism? How does oxygen debt affect the brain? What makes Everest “Everest”? Why does your probability to make mental errorsincrease? Why does heart rate increase at altitude? What is this called? What are the affects of decreased oxygen to the brain? Does this cause brain damage? How is this studied? What are some symptoms of oxygen deprivation? What is Acute Mountain Sickness? What are its initial symptoms? What happens as it progresses? Where else might this happen? Why do climbers return to base camp before ascending further? What is high altitude pulmonary edema (H.A.P.E.)? How does it cause death? Why aren’t bodies removed from Everest? Why do bones remain after other tissues are eliminated? Why is the area above 27,000 ft. called the “death zone”? What happens when your resting heart rate matches your maximum heart rate? What are some specific dangers/emergency situations that may occur under these circumstances? Will David ever reach the summit of Everest Again ?
116
Are there any other examples that you can think of that highlight the physiological effects of the body’s inability to acclimatize to extreme climates?
117
Into Thin Air Jon Krakauer, an experienced climber and outdoor journalist, was sent to climb Mt. Everest in Nepal in the spring of 1996. Late at night on the evening of May 9, 1996, after weeks of grueling climbing, acclimatization to low oxygen at high altitudes, illness, blinding snow, bitter cold, and hurricane force winds, the clients of several climbing organizations from the US, New Zealand, South Africa, and Taiwan reached an altitude of 26,000 feet before making the final ascent to the peak.
118
Jon Krakauer Krakauer and his companions led by professional climbing guides and experienced Sherpas left camp at midnight on May 10th on what developed into a perfect morning for reaching the summit. By 4:00 pm, two full hours beyond the discussed but not enforced mandatory turn around time, the weather conditions change rapidly from tranquil to blizzard in a matter of minutes. Winds are blowing with gale-force strength and as night falls the temperature with wind chill is more than 100 degrees below zero. With no shelter and a shortage of oxygen canisters, 30 individuals are exposed and freezing above 26,000 feet on the barren, icy slopes of Everest. Krakauer loses several climbing partners and climbers from other groups, and two experienced expedition- leading guides.
119
The Climb Written the same day on Everest, but told from a different perspective.
120
Some believe That although “Into Thin Air” was an international best-seller and Jon Krakauer is an accomplished writer and semi-professional climber, his views were distorted during the expedition and led to inaccurate accounts. Whereas Annatoli Boukreev is a more accomplished guide and his account, based on physiology alone, may be more accurate.
121
Who to believe?
122
Is it possible for some to be more physiologically disposed to these extremes?
123
Fall 2010
124
quiz 1.Define negative feedback mechanism and give and example. 2.Define positive feedback mechanism and give an example.
125
Raising the Dead Positive and negative feedback mechanisms Raising the Dead Good idea? Anatomical Planes and Terminology
126
Raising the Dead
127
Deep Trouble What is the name of the cave, and where is it? Who is Dave Shaw and what happened to him? How (Be Specific)? What are the dangers of deep-water diving? Why is it especially dangerous to combine extreme depth with demanding work? What was not anticipated before the dive? How did this affect the dive? What is the danger of having too much nitrogen in the blood? How do the body’s feedback mechanisms work this out? What is the danger of having too much helium in the blood? How do the body’s feedback mechanisms work this out? What are decompression stops? What are recompression chambers (hyperbaric)? How do they work?
128
Is any of this a good idea? Next class: Homeostasis and homeostatic control mechanisms. Homework: Find and UNDERSTAND an example of either a positive or negative feedback mechanism. In the body or elsewhere…(20 points)
129
Further… What is the danger of breathing so rapid and shallow at these depths/altitudes? Why was Don Shirley so interested in mimicking Dave Shaw’s breathing? What does he mean when he says “I actually died with Dave”. Why was the experiment with David Carter similar? How are these experiences the same, how are they different?
130
Raising the Dead Positive and negative feedback mechanisms Raising the Dead Good idea? Anatomical Planes and Terminology
131
Could Dave Shaw have lived if he had people there? Why couldn’t anybody help him?
132
They are both practical examples of gas laws studied in chemistry.
133
Nitrogen Narcosis “Narcing” Nitrogen narcosis or inert gas narcosis is a reversible alteration in consciousness producing a state similar to alcohol intoxication in Scuba divers at depths beyond 30m. Jacques Cousteau famously described it as the "rapture of the deep". Its precise mechanism is not well understood, but it appears to be a direct effect of high nitrogen pressure on nerve transmission. While it was first observed with nitrogen (in air), other gases including argon and hydrogen also cause very similar effects under high enough pressure. Xenon is actually a usable anaesthetic at atmospheric pressure, though it is too expensive to be used in practice. The onset is hard to recognize, its severity is unpredictable, and it can kill, from its own toxic effect or due to the resulting illogical behavior. However the cure for nitrogen narcosis is a simple one, as effects disappear upon ascending to shallower waters
134
CO 2 retention CO 2 retention is a pathophysiological process in which too little carbon dioxide is removed from the blood by the lungs. The end result is hypercarbia, an elevated level of carbon dioxide dissolved in the bloodstream. Various diseases may lead to this state; disturbed gas exchange may lead to impaired excretion of the gas. In addition, breathing air with a high carbon dioxide concentration may also lead to hypercarbia. The principal result of the increased amount of dissolved CO 2 is acidosis (respiratory acidosis when caused by impaired lung function); other effects include tachycardia (rapid heart rate) seizures, coma, respiratory arrest and death.
135
In diving CO 2 retention with its attendant dangers of death from convulsions and hypoxia (low oxygen level) is primarily of concern to the scuba diver due to "skip breathing". Other sources of CO 2 retention are breath-hold diving, breathing in a sealed environment, faulty regulator, exercise at extreme depth and using contaminated air. Symptoms include rapid respiration in 4-6%, rapid pulse rate, shortness of breath in 7-10% and convulsions and unconsciousness in 11-20%. The CO 2 level in the blood is unchanged by the ambient pressure (i.e., the depth) per se, since the partial pressure of carbon dioxide in a scuba diver's blood is a function only of metabolism and the rate and depth of breathing - the same factors that determine blood CO 2 concentration on land.
136
While Diving… All of the CO 2 developed during breathing underwater is exhaled in the bubbles from scuba apparatus and does not increase with depth as do other gases, such as nitrogen, oxygen, carbon monoxide and hydrocarbons. Abnormal carbon dioxide accumulation in the blood can occur from too high a level of metabolism (such as from exercise at depth) and/or inadequate breathing (usually not breathing deep enough or skip breathing). The medical term for high carbon dioxide in the blood is hypercapnia; when the level is high enough it can cause "CO 2 toxicity," which can lead to shortness of breath, headache, confusion and drowning (depending on severity).
137
Elevated CO 2 levels Elevated CO 2 levels play a significant role in oxygen toxicity and in nitrogen narcosis. The acceptable CO 2 level for diving operations is 1.5% surface equivalent (10.5 mmHg); the acceptable level for hyperbaric oxygen therapy operations is one that allows a vent schedule of 4scfm/person displacement
138
Rebreathers With the increased usage of rebreather diving, mainly by the military-but recently by more and more civilian divers, there is the possibility of hypercarbia (high CO 2 levels), among other medical considerations.
139
Sound Familiar? Signs and symptoms that need to be observed are hyperventilation, shortness of breath and tachycardia (rapid heart beat), headache and excessive sweating, mental impairment and finally, unconsciousness. hyperventilationtachycardiasweating
140
What killed Dave Shaw? According to Nuno Gomes, who understands why Shaw had trouble reacting to a body that was suddenly floating instead of anchored. “You don’t think of a new plan while you’re down there. It doesn’t work. Your mind is clouded.
141
What negative feedback mechanisms was enacted that day? Shaw passed out due to toxic levels of CO 2
142
Response: “Today, extreme divers are far exceeding any reasonable physiology capabilities”
143
Is this type if diving responsible?
144
What are some other dangers that divers face?
145
Hyperbaric medicine Hyperbaric medicine is a corollary field associated with diving, since recompression in a hyperbaric chamber is used as a treatment for two of the most significant diving related illnesses, decompression illness and arterial gas embolism
146
Are there any other examples that you can think of that highlight the physiological effects of the body’s inability to acclimatize to extreme climates?
147
Into Thin Air Jon Krakauer, an experienced climber and outdoor journalist, was sent to climb Mt. Everest in Nepal in the spring of 1996. Late at night on the evening of May 9, 1996, after weeks of grueling climbing, acclimatization to low oxygen at high altitudes, illness, blinding snow, bitter cold, and hurricane force winds, the clients of several climbing organizations from the US, New Zealand, South Africa, and Taiwan reached an altitude of 26,000 feet before making the final ascent to the peak.
148
Jon Krakauer Krakauer and his companions led by professional climbing guides and experienced Sherpas left camp at midnight on May 10th on what developed into a perfect morning for reaching the summit. By 4:00 pm, two full hours beyond the discussed but not enforced mandatory turn around time, the weather conditions change rapidly from tranquil to blizzard in a matter of minutes. Winds are blowing with gale-force strength and as night falls the temperature with wind chill is more than 100 degrees below zero. With no shelter and a shortage of oxygen canisters, 30 individuals are exposed and freezing above 26,000 feet on the barren, icy slopes of Everest. Krakauer loses several climbing partners and climbers from other groups, and two experienced expedition-leading guides.
149
The Climb Written the same day on Everest, but told from a different perspective.
150
Some believe That although “Into Thin Air” was an international best-seller and Jon Krakauer is an accomplished writer and semi- professional climber, his views were distorted during the expedition and led to inaccurate accounts. Whereas Annatoli Boukreev is a more accomplished guide and his account, based on physiology alone, may be more accurate.
151
Who to believe?
152
Is it possible for some to be more physiologically disposed to these extremes?
153
fin
154
Happy Thursday-Friday!! Air Mixtures ATP Smarter on Drugs?
155
Objectives Class notes: Stayin’ Alive The “The Death Zone” Anatomical Terminology (Directions and Planes)
156
Anatomical Planes Be able to label transverse sagittal, median, frontal coronal. Know the difference between median and sagittal.
157
Happy Wednesday 1. Wrap-up of body systems 2. Survival needs 3. Homeostasis and homeostatic control mechanisms 4. Why does this guy look so confused?
158
Body Systems Name of system What is it made of? (organs and Structures) What does it do? How is it regulated? What can go wrong? How do we fix it?
159
Maintaining Life Maintaining Boundaries Movement Responsiveness Digestion Metabolism Excretion Reproduction Growth
160
Happy Thursday! Homeostasis and homeostatic control mechanisms Positive and negative feedback mechanisms Deep Trouble Project idea tighten up
162
What could possibly go wrong?
163
Human Chop Shops?
164
Hmmm.
166
Extended space travels
167
Stayin’ Alive Nutrients Oxygen Water Normal Body Temperature Atmospheric Pressure
169
Often Imitated
172
It’s Friday! Already? Do now: Define Technology Give three more examples: 1. 2. 3.
173
It’s Monday! Already? Do now: Define Variable A variable is ___________________ What is the CSU? What is the ESU? Technology: The Bionic Arm Observations Candle Lab Again? Format for writing experiments
174
Happy Monday!!! Lab #1 overview Cavities and linings Anatomical Directions and terms Anatomical Planes
176
Thursday, Thursday Do ya get it? PFM ‘s and NFM’s Quick revisit to Positive and negative feedback mechanisms Raising the Dead Good idea? Anatomical Planes and Terminology
177
Tighten Up Lab #1 Cavities and linings Anatomical Directions and terms Anatomical Planes
178
It’s Monday! Already? 1: Do now 2: Observations 3: Candle Lab Again? 4: Format for writing experiments
179
Do Now Do now: Define Variable A variable is ___________________ What is the CSU? What is the ESU? What are three ways of making observations BEFORE you start your experiment? A good experiment tests __ variable(s) at a time.
180
What could possibly go wrong?
181
Human Chop Shops?
186
It’s FRRRRRIDAYYYY, Already? Really? Bionic Arm? Everest Wrap-up Survival Needs Review CSI
187
What could possibly go wrong?
188
Human Chop Shops?
Similar presentations
© 2025 SlidePlayer.com Inc.
All rights reserved.