What is the physiological mechanisms that keep the hydrogen ion concentration (H+) of blood and body fluids compatible with life?

• Acid-base balance

The body generates __________________ _ so there must be a regulation that occurs to keep the balance.

hydrogen ions

___________________ _ are positively charged ions.

cations

___________________ are negatively charged ions.

anions

What must we have a equal mix of to have a balance?

• Equal mix of cations and anions. Think of them canceling each other out.

What is the Bronsted-Lowry theory say about:

Acid:

Base:

• Acid: any substance that donates a proton to aqueous solution
• Base: any substance that accepts a proton removing it from solution

If body fluids are acidic, they have abnormally high____________________ _.

H + concentration

What are increased H+ ions in the blood called______________________ .

acidemia

What is characterized by the accumulation of H+ in body fluids__________________ .

acidosis

What is the opposite of acidic______________________ .

alkaline

The term ________________ __ is synonymous with base.

alkali

What are body fluids that have abnormally high amounts of base or contain low amounts of H+_____________________________ _

alkaline or basic

The concentration of H+ in body fluids are extremely small. Equal to _________________________________ .

40 billionths of 1 mol per liter

Prefix nano refers to billionths, how would it be written_________________________ .

(We use pH rather than 40 nmol/L)

40nmol/l

Who developed the concept of pH?

He came up with a way to simplify the way pH was expressed.

Danish Chemist in 1909 (Sorenson)

What does the pH scale ranges from________________

0-14

What does chemists and professionals believe the p refers to _ ____________.

power

What is the pH defined as?

Negative logarithm or exponent of the H+

pH is the ______________________ , a ____________ _ in pH indicates an _ __ _______________________.

negative logarithm of H+

decrease

increase in H+

A chemically neutral solution has a pH of __ _____.

7.0

(In this case ONLY) A pH of anything less than 7.0 is considered____________ _ and a pH of anything higher is __ ___ __________.

acidic

alkaline

Hydrogen ions formed in the body arise from____ _ or __ .

volatile

fixed acids

The only volatile acid of significance is _______________________ .

carbonic acid (H2CO3)

What are fixed acids?

Sulfuric and phosphoric acids

What does anaerobic metabolism produce?

Lactic acid (also fixed acid)

How do we balance all of this?

Buffers

What is defined as resisting change in pH when acids or bases are added to it.

Buffer

What is one of the most important blood buffers?

Solution of carbonic acid and its conjugate base HCO3-.

What is a conjugate base?

Remaining anion portion of the acid molecule

Blood buffers are classified as either______________________ or ______________ buffer systems.

bicarbonate

non bicarbonate

What does the bicarbonate system contain?

Carbonic acid (H2CO3) and its conjugate base bicarbonate ions

Why is the bicarbonate buffer system considered an open system?

It is readily removed by ventilation

Nonbicarbonate buffer systems are closed. True or false

true

It is because all components remain in the system

How do we excrete the acid we make and rid ourselves of it?

2 primary organs:

2 primary organs: lungs and kidneys

If what did not happen the buffer systems would eventually be exhausted and pH levels would drop to life threatening levels?

Excrete the acid we make and rid ourselves of it through the lungs and kidneys

What is capable of excreting large amounts of acids within minutes?

lungs

What excrete fixed acids at a much lower speed. From hours to days compared to minutes.

kidneys

The kidneys excrete ________________ __of fixed acids per day.

less than 100mEq

These _______________ __ work together and can compensate when one organ fails.

organs

Normal pH is not affected by______ _ or _______ _.

age

gender

pH=___ _ ________

PaCO2=__________ _

PaO2=________________ _

SaO2%=_ ___________

HCO3-=__ _______

7.35-7.45

35-45 mmHg

80-100 mmHg

95-98%

22-26 mEq/L

What is defined as a blood pH> 7.45?

Alkalemia

What is defined as a blood pH < 7.35?

Acidemia

What is defined by a PaCO2 <35 mmHg

Hyperventilation

What is defined by a PaCO2 >45 mmHg

hypoventilation

What changes the arterial pH in a non respiratory way.

Primary metabolic disturbances

Non respiratory processes that cause acidemia/alkalosis produce______________ _.

What would be the compensatory organ.

metabolic acidosis or alkalosis

lungs

What can change the arterial pH as well causing a respiratory acidosis or alkalosis.

Primary respiratory disturbances

What happens when there is a acid base defect that occurs?

Organ system NOT responsible immediately initiates a compensatory process to counteract the defect.

If reduced ventilation is _______________________ _the kidneys will work to restore the pH to normal by retaining bicarb.

primary defect (respiratory acidosis)

It is important to know what issues that you could see in patients with_____________ and how to treat them to return to normal ________________ _ so they are not at risk for life threatening pH levels.

abnormal ABGs

pH range

What is abnormal low pH?

<7.0 will induce a comatose state or death.

What is abnormal high pH?

<7.80 cause convulsions, tetany, and death

What is specific to CVT pH?

• pH values around 7.10 will result in ventricular arrhythmias and reduce heart contractility.

What does tetany mean?

state of sustained muscle contraction/ spasm

What is step one of classification:

Classify the pH

• Acidosis (lower than 7.35)

• Normal

• Alkalosis (higher than 7.45)

What is step two of classification:

Inspect the PaCO2 (ask if the observed PaCO2 by itself can cause the pH abnormalities)

• Can you explain the pH?

What is step three of classification:

Inspect the bicarb (bicarb is logical factor of non respiratory involvement in acid base disturbances)

• Can you explain the pH

What is step four of classification:

Check for compensation(once identified if you have respiratory or metabolic abnormalities)

• Did the correct organ (lungs, kidneys) system respond? Or at least start to respond?

_____________________ has occurred when the pH has restored to normal.

Full compensation

Compensation can be considered __________ _ if pH is outside of the normal but the non causative component is also abnormal in a way that brings the pH back to normal range.

partial

What does it mean when there has not been enough time to correct the pH but it is moving toward the normal range.

Partial compensation

(PaCO2, HCO3 values high but pH is acidic)

What is the acid base disturbance is so recent that the compensation has not been started.

Uncompensated (pH abnormal, PaCO2 or HCO3 abnormal)

Even with the body’s compensation methods, we still need to treat the _______________________ .

underlying cause of defect

Compensation _____________ __ and ______________________ _ the pH to the normal range but if this is not a chronic condition it will only be a temporary fix.

corrects

restores

Always remember that monitors are to be used as _____________________ , never solely relied on!

adjuncts to assessment

Make sure you have:

• Adequate lighting

• Correct equipment

• Correct patient position

• Enough time

• A way to monitor time

• Complete objectivity

• Be understanding and sensitive to cultural diversity

Symptoms of pulmonary disease can also indicate _____________________ _.

other diseases

More critically ill patients are harder to assess, due to:

• Presence of multiple disease states

• Positioning of the patient

• Critical care environment

• Increased amount of equipment

• Equipment use obscuring physical signs of the disease or or patient’s present state

What is a cough?

• Sensation of irritation in the pulmonary system.

• Stimuli arising in any part of the airways from the pharynx to terminal bronchi

What is Productive vs. nonproductive

• Is there sputum produced?

• Elderly ↓ in productive coughs

• COPD pts.

Sputum evaluation:

Should be from _____________: not from _____________ or __________________

lungs

saliva or postnasal

• Clear

• odorless

• watery

Sputum eval:

• Volume

• Color

• Consistency

• Odor

Sputum examples:
Smokers and COPD:

• Copus
• thick
• mucoid
• grayish

Sputum examples:

Bacterial infections:

• Purulent
• foul smelling
• yellow-brown or green mucoid color

Sputum examples:

Pneumonia

Rusty or golden yellow color

Sputum examples:

Asthma

Clear/white mucoid

Sputum examples:

Hemoptysis:

• Lung Tumors
• Chronic bronchitis
• Pulmonary emboli
• TB
• Sputum is grossly bloody, blood streaked or w/ small pink clots

Sputum examples:

Cardiogenic pulmonary edema

• Pink , sometimes peach in color
• Frothy
• Pressure of ruptured capillaries

What is Dyspnea

• Act of breathing becoming difficult, needing conscious effort
• Appears as SOB

CNS mechanisms of dyspnea

Work of breathing and adequate muscle contraction

Emotional mechanisms of Dyspnea

Hysterical hyperventilation

Max breathing capacity Dyspnea

• 200L/min
• Minute ventilatory requirements
• ↑ exercise and ↓ COPD and
  weaning off ventilators

Abnormal blood gases Dyspnea

• Hypoxemia
• hypercapnia

Dyspnea Caused by:

Inflow limitations

• Obstructive disorders ( Asthma, Chronic bronchitis)

Reduction in pulmonary compliance ( ARDS, Atelectasis)

Resistance to lung expansion
 Pneumothorax
 Pleural effusions
 Pleural thickening
 Inflammation

Increases in dead space
 Pulmonary embolism

Respiratory muscle fatigue
 Underlying disease
 Obstructive conditions
Chest wall trauma

Ask patient:

When and how it started
 Does anything help alleviate it?
You will be able to witness physical indications
 Mouth breathing
 Distressed or anxious
 Rhythm of breathing
 Flaring of nostrils and accessory muscle use ( Respiratory distress)
 Rhythm of pt speech (Can they speak?)
 Gasping
Test:
 Ask pt to breathe in and on exhalation count to 10:
 If they can’t get past 5 or get to 10
 Extreme risk of respiratory collapse

Chest pain: Pulmonary

Upper retrosternal pain

Acute tracheitis

Chest pain: Pulmonary

Retrosternal pain (similar to chest pain (angina)

• Acute mediastinitis
• Pneumomediastinum
• Radiate to arms and neck
• Not related to exertion
• Differential  EKG and cardiac enzymes

Chest pain: Pulmonary

Pleurtic pain > Stretching of inflamed parietal pleura

• Pleurisy
• Pulmonary embolism
• Sharp an stabbing > pericarditis similar (EKG, echo)
• Aggravated by exertion, deep inspiration or cough

Chest pain: Pulmonary

Musculoskeletal:

Chest wall deformities or injury

Signs of pulmonary disease

LOC: Level of consciousness

Alteration of cerebral function
 Changes perception of reality as well
 May require detailed questioning
 Blood gas evaluation commonly
required
 Hypoxemia > PaO2 < 60 mmHg
 Hypoxia= reduction of blood supply to
tissues
Hypoxemia= reduction of oxygen in blood
 Usually coexist
 Can appear similar to signs and
symptoms of alcohol intoxication
 Signs of cerebral hypoxia can be variable
 Restlessness
 Agitation
 Confusion
 Inappropriate sense of well being
 Outbursts of hilarity
 Paranoia
 Irritability
 Combativeness
 Uncooperativeness
 Loss of muscle coordination
 Loss of visual acuity
 CNS suppression
 Stupor, Coma or seizures

Other clinical signs of hypoxia:

 Tachycardia
 Tachypnea
 Dyspnea (possibly)
 Ectopic arrhythmias
 Atach
 PACs
 PVCs
 Bradycardia is a very late and ominous
sign
 Aggressive oxygen and airway treatment

Hypercapnia

 PaCO2 > 45 mmHg
 Resemble CNS depression
 Anesthetics
 Lethargy
 Confusion
 Slurred speech
 Poor coordination
 Somnolence
 Stupor
 Coma
 Headache: cerebral vasodilation
 Tachypnea
 Respiratory acidosis
 Vasoconstriction
 Systemic vasodilation (severe)
 Hypotension
 Combined with hypoxemia

Signs of pulmonary

Respirations:
 Rate, Rhythm and character
 Frequency: 12-20 breaths
per min.
 Increase w/ fever, sepsis, hypercapnia, hypoxemia, acidemia, Emotional
stimuli, CNS lesion, pain and pulmonary emboli
 Dyspnea ≠ Tachypnea
 RR > 28 Bpm= significant
respiratory distress
 RR 28-34 Bpm= need for
intubation

Warnings of
cardiopulmonary collapse:

Warnings of
cardiopulmonary collapse:

 RR> 30 Bpm
 Neurologic deterioration
 Restlessness, lethargy or confusion
 RR < 8 Bpm
 RR low for underlying conditions
 Counting RR:
 Auscultating each breath
 By chest rise
(visualization):
 Does not measure actual breathing
 Could be just effort
 Count # of breaths in one minute

Abnormal Breathing Patterns:

 Kussmal’s breathing: Rapid and deep
 Infarction to midbrain
 metabolic acidosis (DKA)
 Cheyne-stokes: Decreased rate and depth:
 Brain damage
 Severe cardiogenic shock
 Drug induced respiratory depression
 Biot: long periods of apnea:
 Brainstem dysfunction
 Agonal: irregular gasping
 Occurs just before death

Depth of breathing:

 Normal breathing= barely visible
 Visible breathing= Min ventilation has at least doubled
 Excessive deep breathing may indicate:
 Brain damage
 Head injury
 Stroke

Symmetry of breathing:

 Both sides of chest should move together normally
 Lay pt. supine, chest exposed
 Look @ infraclavicular, mid chest, lower ribs and abdomen.
 Observations difficult in: May require palpation
 Obese
 Edema
 Thoracic or abdominal dressings

Asymmetrical movement:

 Pleural effusion
 Obstruction of a major bronchus or loss of lobe (surgery)
 Neuromuscular abnormalities (GB or MG)
 Right main bronchus intubation:
 Ventilates right lobe only
 Left has diminished breath sounds
 Requires chest X-ray evaluation