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Anatomy and Physiology 1111 > Module 19 > Flashcards

Module 19 Flashcards

1
Q

The Urinary System

A

The Urinary System consists of the kidneys, ureters, bladder, and urethra. It assists in controlling the body’s pH, electrolytes, fluid volume, and fluid concentration. The kidneys also produce hormones to regulate red blood cell production and blood calcium levels.

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2
Q

Kidneys

A

Are positioned between the posterior abdominal wall and the peritoneum. Because only the anterior aspect is covered by the peritoneum, they are said to be retroperitoneum. The right kidney is slightly lower than the left.

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3
Q

Ureter

A

Extending from each kidney is a ureter. It is a connection between the kidney and the bladder and is also retroperitoneal. Both are connected to the bladder.

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4
Q

Bladder

A

The bladder is a hollow, distensible organ in the pelvic cavity, designed to hold and help excrete urine. The bladder can hold an average of 700-800 ml of urine.

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5
Q

Urinary System Functions

A
  • Regulation of Electrolytes: control levels of various anions and cations
  • Regulation of pH: control of body pH by secreting H+ into the urine and return of HCO3- back to the blood.
  • Regulation of blood volume: Adjusts blood volume by conserving or eliminating urine.
  • Regulation of blood pressure: Adjusts blood pressure by conserving or eliminating Na+ or urine
  • Maintenance of blood osmolarity: Control of blood concentration
  • Production of hormones: Calcitriol (active vitamin D) to increase calcium levels; erythropoietin to increase red blood cell production.
  • Regulation of blood glucose levels: Release of glucose, produced by gluconeogenesis, into the blood.
  • Excretion of wastes: Excretion of ammonia, urea, bilirubin, creatinine, uric acid, and other wastes
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6
Q

External Structure of the Kidney

A

Renal Capsule
- Protects and maintains the shape of the kidney

Adipose Capsule
- Maintains the position of the kidney

Renal Fascia
- Anchors the kidney to the abdominal wall and neighboring structures

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7
Q

What are the 2 Regions of the Kidney?

A

Internally, the kidney has two distinct regions:

Renal Cortex

  • Outermost region
  • Extends between the renal pyramids (renal columns)

Medulla
- Renal pyramids: are triangular structures within the medulla that appear striated due to the presence of the renal tubules and ducts. Have renal papillae and drain into the calyces.

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8
Q

Nephrons, Minor Calyx, Major Calyx, and Renal Pelvis

A

Each kidney has approximately 1 million nephrons. The nephron is the main funtional unit of the kidney. Urine produced by the nephrons drains from the apices (renal papillae) of the pyramids.

The urine from each pyramid will enter a cup-like structure called a minor calyx. There are 8-18 per kidney.

2-3 minor calyx drain into a major calyx. Each kidney has 2-3 major calyces which will drain into one large cavity called the renal pelvis.

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9
Q

What are the 2 Vascular Features of the Kidneys?

A

There are 2 unique vascular features of the kidneys:

  • First, the glomerular capillaries are positioned between two groups of arterioles.
  • Second, unlike any other organ of the body, there are two sets of capillaries, the glomerular capillaries and the peritubular capillaries.
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10
Q

Path of the Renal Blood Flow

A
  • Abdominal aorta
  • Renal artery
  • Segmental arteries
  • Interlobar arteries
  • Arcuate arteries
  • Interlobular arteries
  • Afferent arterioles
  • Glomerular capillaries
  • Efferent arterioles
  • Peritubular capillaries (including vasa recta in juxtamedullary nephrons)
  • Interlobular veins
  • Arcuate veins
  • Interlobar veins
  • Renal vein
  • Inferior vena cava
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11
Q

What are the 2 Groups of Structures of the Nephron?

A

The nephron includes two groups of structures:

Renal corpuscle: consists of the glomerulus (glomerular capillaries) and the glomerular capsule; it is the filtering structure of the nephron

Renal Tubules: their role is to modify the filtrate (product of filtration) to facilitate the final product of urine formation. They are named based on their shape and/or to their position related to the glomerulus. The proximal convoluted tubule is a tightly-coiled tubule attached directly to the glomerulus.

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12
Q

What are the 2 Types of Nephrons?

A

The only difference between the 2 types of nephrons is simply the length of the loops of Henle:

Cortical Nephrons: 80-85% of nephrons are cortical. The majority of the nephron is in the cortex, and the Loop of Henle extends only a short distance into the medulla

Juxtamedullary Nephrons: 15-20% of nephrons are juxtamedullary. Their Loops of Henle extend into the deepest regions of the renal pyramids. These long loops will play a role in the ability to concentrate the urine.

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13
Q

The Loop of Henle, Distal Convoluted Tubule, Collecting Duct, Papillary Duct, and Minor Calyx

A

Forms a hair-pin turn by connecting two lengths, or limbs of the tubule, the ascending and descending. The final tubule is the distal convoluted tubule which is similar to the proximal tubule in that it’s tightly curled, but it’s further away from the glomerulus.

Several distal convoluted tubules come together to form a single collecting duct. Many collecting ducts merge to form a papillary duct, which empties into the previously mentioned minor calyx.

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14
Q

The Renal Corpuscle

A

Is located in the cortex and is the structure of the nephron that filters the blood. It consists of 2 components:

  • glomerulus
  • glomerular capsule
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15
Q

Glomerular Capsule

A

Receives fluid from the filtration process of the glomerulus. Is the receptacle for the filtered blood before it enters the tubules. Because it isn’t blood anymore, but it isn’t urine yet, it is called glomerular. So, the fluid entering the nephron is blood, within the nephron is glomerular filtrate, and exiting the nephron it is urine.

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16
Q

Glomerulus

A

Has glomerular capillaries that filter blood .

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17
Q

Juxtaglomerular Apparatus

A

Is formed by a combination of cells from the ascending limb of the loop of Henle and an afferent arteriole for each nephron.
- This is why this group of cells is called the macula densa

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18
Q

Macula Densa

A

Part of the Juxtaglomerular Apparatus

Densely-packed columnar cells in the ascending loop of Henle. They are arranged next to the afferent arteriole

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19
Q

Juxtaglomerular Cells

A

The wall of the afferent arteriole contains modified smooth muscle cells that control the arteriole’s diameter. Because of their position, these cells are called the juxtaglomerular cells, and together with the macula densa they control blood pressure within the kidneys.

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20
Q

Renal Functions

A

Glomerular Filtration: Production of glomerular filtrate through the filtrate of waste-laden blood by the glomerulus

Tubular Reabsorption: Process of returning important substances from the glomerular filtrate back to the bloodstream

Tubular Secretion: Process of transporting substances from the bloodstream into the glomerular filtrate.

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21
Q

What are the 3 Layers that Form the Glomerular Filtration Membrane?

A
  • Capillary Endothelium
  • Basal Lamina
  • Podocytes

The capillary endothelium allows the passage of all blood solutes, but disallows the formed elements. The basal lamina further limits filtration by large proteins from being lost into the capsule. Filtration slits limit passage of even small proteins.

Less than 1% of even the smallest proteins can pass this three-layer membrane.

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22
Q

Capillary Endothelium

A

The first layer is simply the endothelium of the glomerular capillaries. These capillaries are fenestrated capillaries, so they are much more permeable than the more common continuous capillaries of the vascular system

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23
Q

Podocytes

A

The visceral (deep) layer of the glomerular capsule forms another layer. This tissue is formed by unique cells called Podocytes.

  • These cells have numerous food-processes (pedicels) that extend from the Podocytes. The pedicels have small spaces between them called filtration slits.
  • The permeability of this membrane can be controlled by the amount of space provided by the food-processes of podocytes.
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24
Q

Basal Lamina

A

Lastly, there is a layer of connective tissue (basal lamina) sandwiched between the endothelium and the podocytes.
- Limits the passage of large proteins.

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25
Q

Glomerular Filtration Rate (GFR)

A

The amount of glomerular filtrate formed each minute is called the glomerular filtration rate. The body averages about 115 ml/min; men are slightly higher than women. This results in approximately 180 L of glomerular filtrate being produced per day.

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26
Q

Net Glomerular Filtration

A

Net glomerular filtration = Forces favoring filtration - forces opposing filtration.

Glomerular Blood Hydrostatic Pressure (GBHP)

  • Favors - 55 mmHg (encourages filtration)
  • Renal blood pressure

Capsular Hydrostatic Pressure (CHP)

  • Opposes - 15 mmHg
  • Pressure from accumulated filtrate in the glomerular capsule

Blood Colloid Osmotic Pressure (BCOP)

  • Opposes - 30 mmHg
  • Osmotic Pressure from formed elements and proteins in the blood.

= On average, GBHP wins by +10 mmHg

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27
Q

Filtration

A

The process of filtration is the use of pressure to force fluids, including the solutes, through a semi-permeable membrane. The filtration membrane works for this function because the glomerular capillaries provide a large surface area, the membrane is thin and porous, and the capillary blood pressure is high.

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28
Q

What are the 3 Filtration Pressures, their Causes and Actions?

A

Net Filtration Pressure (GBHP-CHP-BCOP)

Glomerular Blood (capillary) Hydrostatic Pressure (GBHP)

  • Caused by: blood pressure in capillaries - 55 mmHg
  • Action: favors filtration

Capsular Hydrostatic Pressure (CHP)

  • Caused by: fluids present in capsular space - 15 mmHg
  • Action: opposes filtration

Blood Colloid Osmotic Pressure (BCOP)

  • Caused by: osmotic pressure from proteins remaining in the plasma - 30 mmHg
  • Action: opposes filtration
29
Q

Controlling the Glomerular Filtration Rate (GFR). What are the 3 Mechanisms the Body Uses to Maintain GFR?

A

The GFR needs to be held fairly constant. If the GFR drops too low, there is a buildup of waste products in the blood. If the GFR is too high, there may not be adequate time to reabsorb essential nutrients, and they would be lost in the urine. To maintain an appropriate GFR, the body uses 3 mechanisms:

  1. Renal autoregulation
  2. Neural regulation
  3. Hormonal regulation
30
Q

Renal Autoregulation of GFR

A

Myogenic Mechanism: If the blood pressure is high, the afferent arteriole can constrict to reduce blood flow to the glomerulus. This would reduce the GFR.

Tubuloglomerular Feeback: This is controlled by the juxtaglomerular apparatus (JGA). The cells of the macula densa detect increased amounts of electrolytes and water showing up in the distal tubules of the nephron.

  • If these substances are present in increased amounts, it may be due to an increased GFR, so adequate time was not available to reabsorb them.
  • To minimize electrolyte loss, the JGA inhibits he release of NO (nitric oxide), which is a potent vasodilator. So with less NO present, the arterioles will constrict and decrease the GFR and give time to reabsorb the electrolytes
31
Q

Neural Regulation of GFR

A

The renal blood vessels are mainly controlled by the sympathetic nervous system. Norepinephrine release from symapthetic post-ganglionic neurons causes both the afferent and efferent arterioles to constrict.
- AT rest, this influence in minimal, but with greater norepinephrine release, there is greater constriction of teh afferent arteriole, therefore less blood flow to the glomerulus and a lower GFR.

32
Q

Hormonal Regulation of GFR

A

Two main hormones contribute to the GFR:

Angiotensin II: is a potent vasoconstrictor of the renin-angiotensin-aldosterone system (RAAS). So with increased amounts of angiotensin II, the GFR will decrease

Atrial Natriuretic Peptide (ANP): is produced by cells in the atria of the heart. ANP causes cells within the glomerulus to relax, thereby increasing the GFR by increasing the gloerular surface area.

33
Q

Glomerular Filtrate

A

Glomerular filtrate is blood minus the formed elements (cells) and the majority of the plasma proteins. Normally, 16-20% of the plasma in the afferent arterioles becomes filtrate.

Through the filtration process, an average of 180 L of glomerular filtrate is produced per day. This means there is more filtrate produced in one hour than the total volume of the blood in the body at any given time.

34
Q

Tubal Reabsorption

A

The process of returning important substances from the glomerular filtrate back to the body. If 180 L of filtrate are produced per day, but only 1-2 liters of urine are excreted, a large amount of water and solutes (99%) must be returned to the blood.

  • 99% of filtrate is reabsorbed
  • 65% of the water, sodium, and potassium, 100% of the glucose and amino acids, and 50% of the urea are reabsorbed in the proximal convoluted tubule.

The majority of solute and water reabsorption occurs in the proximal convoluted tubule. To maximize reabsorption capacity, cells of the proximal convoluted tubule are cuboidal epithelium with prominent microvilli.

35
Q

What are the 2 Routes a Substance can be Reabsorbed?

A

A substance can be reabsorbed from the filtrate through one of two routes:

Paracellular Reabsorption: between the renal tubule cells

Transcellular Reabsorption: though the renal tubule cells. For this reabsorption to take place, the substance must cross the apical membrane of the tubule cell, pass through the cytoplasm, and enter into the interstitial fluid by crossing the basolateral membrane.

36
Q

Transport Maximum

A

Transport proteins are present on the surfaces of cells to actively reabsorb many of the solutes.

Each transport protein has a transport speed limit, referred to as the transport maximum.

  • The presence of solute above this limit will result in the excretion of the excess solute in the urine.
  • To maintain osmotic balance, water will follow the solute, resulting in diuresis. (ex. the renal threshold of glucose is 180-200 mg/dl. When this level is exceeded, the glucose will be excreted in the urine.
37
Q

Glucosuria

A

Diabetics who do not keep their blood glucose level under 200 mg/dl can exceed the renal transport maximum for glucose. This will result in the loss of glucose into the urine, a condition called glucosuria.

38
Q

Reabsorption of Water

A

All of the water reabsorbed in the kidneys is controlled by osmosis.

Obligatory Reabsorption:

  • 90% of water reabsorption
  • Water follows solutes. Water follows concentration gradient throughout most of the nephron.

Facultative Reabsorption:

  • Variable water reabsorption to adapt to specific needs.
  • Regulated by antidiuretic hormone (ADH) in the renal tubules and collecting ducts.
  • Accounts for 10% of water reabsorption
39
Q

Tubular Secretion

A

The transport of substances from the bloodstream to the glomerular filtrate.

Occurs throughout the nephron

Has 2 main functions:

  • Secretion of hydrogen ions controls pH
  • Hydrogen and ammonium ions are secreted and bicarbonate conserved to maintain physiological pH.

Secretes substances
- H+, K+, NH4+, creatinine, and some drugs

40
Q

Influence of Renin-Angiotensin-Aldosterone System

A
  • Decrease in renal blood pressure
  • Causes decreased pressure in the afferent arterioles
  • Juxtaglomerular cells secrete the hormone renin
  • Renin converts angiotensinogen to angiotensin I
  • Angiotensin converting enzyme (ACE) converts angiotensin I to angiotensin II
  • Causes vasoconstriction of the afferent arteriole
  • Enhances Na+ and Cl- reabsorption in proximal convoluted tubule
  • Stimulates the adrenal cortex to secrete aldosterone. Increases Na+ and Cl- reabsorption and secretion of K+ in the collecting duct.
41
Q

Influence of Antidiuretic Hormone (ADH)

A
  • Osmoreceptors in the hypothalamus detect and increase in the blood concentration
  • Posterior pituitary secretes ADH
  • Cells of the distal convoluted tubule and collecting duct insert aquaporin-2 proteins (water channels) in their apical membranes.
  • Aquaporin channels increase water permeability and reabsorption of water.
42
Q

Countercurrent Mechanisms

A

Countercurrent implies two fluids flowing in opposite directions.

  • Loop of Henle
  • Vasa recta of the juxtamedullary nephrons

The countercurrent mechanisms facilitate the production of concentrated urine

  • Fluid volume in the body must be held constant
  • Fluid intake and use are not constant

Two mechanisms
- Countercurrent multiplier and countercurrent exchange

43
Q

Countercurrent Multiplier

A

Mechanism to concentrate the urine, facilitated by the loop of Henle.

  • The goal is to create an interstitial concentration gradient in the medulla
  • To concentrate the urine, osmosis must take place
  • As filtrate flows down the descending limb, it becomes more concentrated (Reabsorption of water)
  • As filtrate flows up the ascending limb, it becomes less concentrated (reabsorption of Na+ and Cl- by active transport)
44
Q

Steps for the Countercurrent Multiplier

A
  • The interstitial fluid and glomerular filtrate become progressively more concentrated the deeper they are in the medulla. This is because water is reabsorbed from the filtrate as it flows down the descending limb of the loop of Henle.
  • The cells of the ascending limb of the loop of Henle actively transport solutes into the interstitial fluid, but the limb is not permeable to water. Because solutes are leaving the filtrate, it becomes less concentrated as it flows up the ascending limb.
  • Water and urea are reabsorbed by cells of the collecting duct. The water diffuses into the vasa recta, but the tubule cells deep in the medullar are permeable to the urea.
  • The exchange of urea between the renal tubules and the interstitial fluid is called urea recycling.
45
Q

Countercurrent Exchange

A

Mechanism to provide oxygen and nutrients via the vasa recta without disrupting the interstitial concentration gradient.

Urea Recycling

  • Water and urea are reabsorbed from the collecting duct
  • Water diffuses into the vasa recta
  • Urea can diffuse into the lower portions of the loop of Henle
46
Q

Physical and Chemical Characteristics of Normal Urine

A
  • Volume: 1-2 liters per day
  • Color: Variable shades of yellow, reflecting concentration, but diseases and conditions can cause urine to be red, brown, orange, etc.
  • Turbidity: Fresh urine is typically clear, but it can be cloudy, due to contamination or urinary disease/conditions.
  • Odor: Mild ammonia-like odor, but other odors can be apparent with various diseases/conditions.
  • pH: Variable, 4.5-8.0;average, 5.0-6.5
  • Specific gravity: 1.005-1.025
    Specific gravity (density) is the weight of the urine, compared to the equivalent volume of water.
47
Q

Tests for Renal Function

A

Blood Urea Nitrogen (BUN)
- Measure the nitrogen in the blood due to the amount of urea present.

Plasma Creatinine
- Creatinine is a waste product of muscle tissue

Urea and creatinine are both waste products
- Increased amounts in the blood commonly represent a decreased glomerular filtration rate

48
Q

Urinalysis (UA) Test

A

Biochemical Tests

  • Urine dipstick test
  • 1-10 absorbent pads, each detecting a different chemical. (aluminum, glucose, bilirubin, blood, evidence of white blood cells, and bacteria, etc.)

Microscopic Test
- Sediment from centrifuged urine sample is viewed under a light microscope. (white blood cells, red blood cells, yeast, bacteria, etc)

49
Q

Ureters

A

A ureter, one originating from each kidney, transports urine from the renal pelvis to the bladder :

  • Peristalsis
  • Hydrostatic Pressure
  • Gravity

The ureters are approximately 10-12 inches long and attached obliquely to the base of the bladder. The mucous membranes are lined with:

  • Transitional epithelium to allow distensibility
  • Mucus to protect from solutes and low pH
50
Q

Urinary Bladder

A

The bladder is a hollow, distensible organ that is located posterior to the pubic symphysis in the pelvic cavity. It can hold 700-800 ml of urine

  • Trigone: a triangular-shaped area at the base of the bladder formed by the openings of the ureters and urethra.
  • Folds (rugae): are folds in the mucus membrane lining that provide for the bladders distensibility.
  • Detrusor muscle: surrounds the mucosal layer. It contracts to assist in emptying the bladder (inner-longitudinal, middle-circular, and outer-longitudinal muscle fibers)
  • Adventitia: the superficial layer of the bladder composed of areolar connective tissue located on the posterior and inferior surfaces and continuous with the ureters.
  • Serosa: A layer of visceral peritoneum on the superior surface.
  • Internal and External urethral sphincters: control urine release from bladder. Circular fibers around the urethra form the internal sphincter. Deep skeletal muscles of the perineum form the external urethral sphincter.
51
Q

Micturition

A

Also called urination or voiding; the process of releasing urine from the urinary bladder. Is a voluntary and involuntary process. Micturition reflex:

  • Stretch receptors are stimulated when the bladder contains 200-300 ml.
  • Parasympathetic response stimulates contraction of the detrusor muscle and relaxation of the internal urethral sphincter (involuntary).
  • Consious sensation of bladder fullness
  • Inhibition of somatic neurons to external urethral sphincter.
  • Voiding.
52
Q

Male vs. Female Urethra

A

Male:

  • 8 inches long
  • Three regions: prostatic, membranous, and spongy
  • Shared with the reproductive system

Female:

  • 1.5 inches long
  • Located between the clitoris and the vaginal opening
  • Shorter length contributes to bladder infections
53
Q

Effects of Aging on the Urinary System

A
  • Decreased blood flow to the kidneys
  • Decreased number or function of glomeruli
  • Decreased size, capacity, and function of the urinary bladder
  • Nocturia
  • Urinary incontinence or retention.
54
Q

Fluids

A

Body Fluid:

  • Water and solutes in the body’s fluid compartments
  • 60% of body mass

Intracellular Fluid (2/3) - Fluid within cells

Extracellular (1/3) - Fluid outside cells

  • Interstitial fluid: fluid in tissues that “bathe” the cells
  • Plasma, glomerular filtrate, lymph, CSF, GI, synovial, ears, eyes, pleural, pericardial, and peritoneal
55
Q

Fluid Balance

A

Fluid balance doesn’t mean that the same amount of fluid is in each compartment. It simply means that the fluids are present in the correct proportions. Moving water between the intracellular and interstitial compartments is accomplished by osmosis, so the solute concentration becomes very important.

56
Q

Fluid Intake and Output

A

Most of the water gained by the body on a daily basis (2500 ml) comes from one source, ingestion. The body loses about 2500 ml of water per day as well.

Water Gain: 2500 ml

  • Metabolic water (300 ml)
  • Ingested foods (700 ml)
  • Ingested liquids (1600 ml)

Water Loss (2500 ml)

  • GI Tract (100 ml)
  • Lungs (300 ml)
  • Skin (600 ml)
  • Kidneys (1500 ml)
57
Q

Regulation of Daily Water Gain

A

Thirst center is located in the hypothalamus

Dehydration

  • Water loss exceeds gains
  • Decreases blood pressure
  • Increases blood osmolarity

Other receptors for dehydration include the kidneys, baroreceptors in the arteries, and neurons in the mouths that detect dryness

58
Q

Water movement

A

Changes in osmolarity will cause water to move from one compartment to another. These water movements can be compensated for if they aren’t sudden or excessive. The kidneys can excrete water at the rate of about 15 ml/minute

Excessive Water Consumption:

  • A decrease in plasma and interstitial osmolarity causes water to move into the intracellular environment, resulting in cellular swelling
  • water intoxication
59
Q

Water Intoxication

A
  • Excessive blood loss, sweating, vomiting, or diarrhea coupled with intake of plain water
  • Decreased Na+ concentration of interstitial fluid and plasma (hypoatremia)
  • Decreased osmolarity of interstitial fluid and plasma
  • Osmosis of water from interstitial fluid into intracellular fluid
  • Water intoxication (cell swells)
  • Convulsions, coma, and possible death
60
Q

Distribution of Anions and Cations

A

Extracellular:

  • Sodium
  • Chloride
  • Bicarbonate
  • Calcium

Intracellular:

  • Protein anions
  • Potassium
  • Magnesium
  • Phosphate
  • Sulfate
61
Q

Buffers

A

Buffers are molecules that have the ability to bind H+, thus reducing the pH of the solution. The H are not removed from the body, they are simply tied up. Common buffering systems include:

  • Protein buffering systems
  • Carbonic acid-bicarbonate buffering system
  • Phosphate buffering system
62
Q

Protein Buffering System

A

Most abundant buffering system in the plasma and intracellular fluid. The carboxyl functional group can bind H+ and side chains on 7 to 20 amino acids can bind H+.

63
Q

Carbonic Acid-Bicarbonate Buffering System

A

The bicarbonate ion (weak base) can bind to H+ to form carbonic acid (weak acid)

64
Q

Phosphate Buffering System

A

Monohydrogen phosphate (HPO4- a weak base) can bind H+ and form dihydrogen phosphate (H2PO42 a weak acid)

65
Q

Respiratory Control of pH

A
  • Excessive accumulation or loss of CO2
  • Alter rate and depth of ventilation to exhale or retain CO2
  • Hyperventilation increases the pH
  • Hypoventilation decreases the pH
  • Can take place in a couple of minutes
66
Q

Renal Control of pH

A

Metabolic reactions produce large amounts of acids.

The kidneys can secrete large amounts of H+

  • H+ are exchanged for Na+ in the proximal convoluted tubule.
  • Proton pumps in the collecting duct

The collecting ducts an secrete H+ when the pH is low and HCO3- when the pH is high

67
Q

Acidosis and Alkalosis

A

Normal Blood pH is 7.35-7.45

  • Acidosis: Blood pH below 7.35
  • Alkalosis: Blood pH above 7.45
68
Q

Respiratory Acidosis and Alkalosis

A

Respiratory Acidosis: any condition that results in inadequate exhalation, thus accumulation of CO2

  • Hypoventilation
  • Emphysema
  • Overdose of respiratory-supressive drugs

Respiratory Alkalosis: exhalation of too much CO2

  • Severe anxiety
  • Oxygen deficiency
69
Q

Metabolic Acidosis and Alkalosis

A

Metabolic Acidosis:

  • Decrease in plasma HCO3-. Diarrhea and renal dysfunction
  • Non-respiratory acid accumulation. Ex. ketosis, lactic acid
  • Failure of kidneys to secrete H+

Metabolic Alkalosis:

  • Non-respiratory acid loss: vomiting
  • Excessive HCO3-. Ex. alkaline drugs (antacids)

Anatomy and Physiology 1111 (7 decks)

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