Pulmonology 5

Cleanses, warms, & moistens air

Distributes air to deeper parts of the lung

Dilation/constriction of smooth muscle determines ease of air flow; Defense – mucociliary transport system

Site of Gases Exchange

Defined as the exchange of air between the atmosphere and the alveoli.

occurs in three stages: inhalation & gas exchange (between alveoli-capillaries & blood-tissues); oxidative metabolism (in cells) generates CO2 & ATP; Tissue-blood gas exchange & exhalation to remove CO2

is the airflow in the lungs

inhalation & gas exchange (between alveoli-capillaries & blood-tissues).

- oxidative metabolism (in cells) generates CO2 & ATP

Tissue-blood gas exchange & exhalation to remove CO2

resides in Brainstem

originates in cerebral cortex and can override autonomic control.

Diaphragm and accessory muscles; Coordinated through phrenic, intercostal, cranial and cervical nerves; Chemoreceptors and mechanoreceptors

blood is 100% saturated

blood is typically 75% saturated

0-60mmHg -slope

60-100mmHg -slope

provides an inexpensive, noninvasive alternative means of monitoring hemoglobin saturation with oxygen.

Affected by: Severe anemia, Abnormal hemoglobin, Presence of intravascular dyes & Lack of pulsatile arterial blood flow

falls with increasing altitude.

Shape and Symmetry: anterior and posterior chest

Assesses airflow through the tracheobronchial tree

soft, low-pitched. Heard over most of lung fields.

medium pitched. Heard over main bronchus & (R) upper posterior lung.

loud, high-pitched. Only heard over trachea.

Inspiration > expiration

Inspiration = expiration

Expiration slightly > inspiration

Added or extra sounds; Are always abnormal and usually indicate underlying respiratory and/or cardiac pathology

discontinuous; heard more often in inspiration; not usually cleared by coughing; dry or wet; fine, medium or coarse

small airways forced open in disruptive fashion

continuous; fog horn or snoring quality usually clear with coughing

air passing through an obstructed airway. thick secretions, tumor

continuous, musical, high-pitched sound (tea kettle); most commonly heard in asthma and is diffuse and usually bilateral

forceful air flow through a constricted airway

in a pediatric patient suggests foreign body aspiration

Inflamed pleural surfaces rubbing together

Pleural sound; Like leather rubbing together; Evanescent and depend on amount of fluid in pleural space

transmitted voice sounds

Assess anywhere on chest where adventitious sounds are heard; Normally voice sounds on auscultation are muffled & unclear

Increased transmission of voice sounds indicate

E” is heard as “A”

“99” sounds louder, clearer

whispered sounds are clear

An uncomfortable awareness of breathing, not appropriate to the level of exertion

Chest “tight”; “Can’t get enough air in”; “Wake up in middle of night short of breath”; “Short of breath”; ask for Scale of zero to ten

Dyspnea onset minutes or hours

Dyspnea develops over weeks to months

Acute MI; Congestive heart failure, Cardiac tamponade

Bronchospasm, Pulmonary infection – bronchitis, pneumonia, Pulmonary embolism Pulmonary edema, Pneumothorax, Upper airway obstruction

Asthma, COPD, Interstitial lung disease, Cardiomyopathy

History and physical exam lead to accurate diagnoses in approx 2/3 of patients

Oximetry/ABG; CXR; Spirometry; CBC; ECG

Treat the cause; Oxygen; Pulmonary rehab; Treat anxiety

Clears the tracheobronchial tree of mucus, foreign particles, and noxious aerosols

One of the most common reasons for outpatient visits; May impair sleep and social functioning

Cough < 3 weeks

Cough >3 weeks

women > men to develop

Stimulated cough centers in resp tract send impulses to cough center in

Most commonly associated with URI; Other causes pneumonia, aspiration, pulmonary embolism, pulmonary edema

Low-grade chronic bronchitis; Increased intensity and intractability of pre-existing cough – think lung cancer

Upper airway cough syndrome (postnasal drip); Asthma; Gastroesophageal reflux (GERD)

ACE inhibitor-induced cough

Fatigue, Insomnia, Headache, Urinary incontinence, Rib fractures (ribs 5-7)

History and physical exam [Timing of cough, Sputum production, Nasal discharge, Frequent throat clearing, Wheezing] Chest x-ray esp in smokers or fever/wt loss patients

Treat underlying cause; Eliminate irritant exposures; Smoke, occupational agents;

Persistent cough after URI (think)

Expectoration of blood originating below the vocal cords

Most likely from bronchial arteries (under more pressure than pulmonary circulation)

upper resp tract bleeding and upper GI bleed

Bronchitis; Bronchogenic carcinoma; Pneumonia

Infection (TB most common cause of hemoptysis worldwide); Goodpasture’s syndrome, Wegener’s granulomatosis, Auto-immune (e.g., lupus pneumonitis), Iatrogenic (drug-induced, radiation), Cocaine-induced

A-V malformation; Pulmonary embolism; Elevated pulm cap pressure (mitral stenosis or LVH); Iatrogenic (Swan-Ganz catheter)

History and physical exam; Chest radiograph; Hematocrit; U/A and renal function; Coag profile; Further eval – bronchoscopy/HRCT

Treat underlying cause; Risk factors for tumor - aggressive workup [ >40 yo, >40 pack yr history of smoking, > 1 week of hemoptysis]

substance that can donate a H+ ion (Lowers pH)

substance that can accept a H+ ion (Raises pH)

Metabolism of carbohydrates & fats generates 15,000 mmol of CO2; CO2 combines w/ water to form H2CO3

Metabolism of proteins forms 50-100 mmol of acid which the kidney must excrete

oxidation of sulfur-containing amino acids generates

compound that binds H+ when the [H+] rises and releases it when the [H+] falls. The body buffers are primarily weak acids (HPO4-2 + H+ H2PO4-)

HA

H+=

A¯=

Help in Diagnosis; Measure Respiratory Function; Make Changes in Treatment, Ventilator Settings, Monitor Acid Base Balance, For Example DKA

pH Measures

pCo2 Measures

pO2 Measures

HCO3 Measures

SaO2 Measures

BE Measures

Arterial Blood Gas Measures

Normal Value: pH

Normal Value: pCo2

Normal Value: pO2

Normal Value: HCO3

Normal Value: SaO2

Normal Value: BE

CO2 is an acid and reflects lung function; causes

HCO3 is a base and reflects Kidney function; causes

exerting opposite effect on pH

are highly reactive especially with proteins

There is a change in charge distribution that leads to a change in molecular configuration which leads to a change in protein function

The H+ concentration varies little from 40 nanomol/L & is regulated by:

Control of partial pressure of carbon dioxide is by

Control of plasma bicarbonate concentration is by changes in

maintain the correct balance of substances in the body including H+ and HCO3-

The vast majority of the acid produced per day is buffered and removed when

Kidneys excrete acid via

Kidneys excrete acid via

BICARBONATE BUFFERING SYSTEM: Under the control of the kidneys:

BICARBONATE BUFFERING SYSTEM: Under the control of the lungs:

+ =hydrogen ion concentration in nmol/L

#NAME?

#NAME?

Compare Bicarb from

The pH must be defended and maintained near

HOW DOES THE KIDNEY REGENERATE BICARBONATE?

URINARY ACIDIFICATION

normal pH

normal CO2

normal HCO3

decrease pH; decrease HCO3, decrease CO2

decrease pH, increase HCO3, increase CO2

increase pH, increase HCO3, increase CO2

increase pH, decrease HCO3, decrease CO2

causes Anion Gap METABOLIC ACIDOSIS (AGMA)[MUDPILERS]

Anion Gap =

Diarrhea, lose

Acid w/o Cl added; H+ buffered HCO3; Anion is added to non measured pool to inc AG

Uretero sigmoidoscopy, Small Bowel Fistula, Excess Chloride & Diarrhea(Most Common), Carbonic Anhydrase Inhibitor/CRF, Renal Tubular Acidosis, Addison’s Disease, Pancreatic Fistula

HYPERCHLOREMIC METABOLIC ACIDOSIS=

IF YOU GET ACIDOTIC FROM DIARRHEA, WHAT DOES THE KIDNEY DO?

How does the kidney make more bicarb?

to differentiate between renal and extrarenal causes of NAGMA.

U[Na] + U[K] – U[Cl]

Normal Urine Anion Gap (UAG)

Decreased UAG < -10

Increased UAG > +10

Kussmaul’s respirations

decreased LOC leads to Coma; Weakness, decreased DTRs, Tachycardia( increased CO to decreased CO that leads to Hypotension and Dysrhythmia; Kussmaul’s respirations; Warm, flushed skin & mucous membranes; Anorexia, Nausea and Vomiting, increased K+

Hydration, Correct the underlying cause: Insulin, Antidiarrheal medications, Dialysis. Note: Sodium Bicarb is not routinely given

Lungs fail to eliminate CO2

CNS Depression: Sedatives, CVA, Head trauma

Neuromuscular Disease: Myasthenia, GBS, Polio, Muscular dystrophy, hypokalemia

Impaired Lung Mechanics: Pleural effusion, pneumothorax, crush injury

Acute airway Obstruction: Foreign body aspiration, tumor, laryngospasm, bronchospasm

Acute Respiratory Disease: Severe Pneumonia, Pulmonary Edema

Lungs fail to eliminate CO2

COPD, Pickwickian Syndrome, Thoracic Cage, Limitations: Kyphoscoliosis, Scleroderma, Chronic Neuromuscular diseases

decreased LOC, Weakness, decreased DTRs, Ineffective respiratory efforts, increased [K+] if acute; Tachycardia leads to increased CO to decreased CO to Hypotension and Dysrhythmia

Maintain patent airway with enhanced gas exchange: Meds, O2, Pulmonary toilet, ventilatory support, monitor ABGs to make appropriate adjustments in therapy; Assess LOC frequently; Modify diet to Low carbohydrate and high fat

A PRIMARY INCREASE IN HCO3

THE PATHOGENESIS OF CHRONIC METABOLIC ALKALOSIS INVOLVES TWO DISTINCT PHYSIOLOGICAL DERANGEMENTS

by either an addition of bicarbonate /a loss of acid or /a loss of a fluid containing proportionally more chloride than bicarbonate

H+ loss from ECF space, HCO3- retention, Contraction alkalosis

Decreased ECF/Chloride depletion, Persistent mineralocorticoid excess, Hypercapnia, Potassium depletion(profound)

Urine Chloride < than 15 mEq/L; Extracellular Fluid Contraction; Saline responsive (corrects volume contraction)

Urine Chloride > 15 mEq/L; Associated with excess mineralocorticoid; Associated with Hypokalemia; Saline unresponsive

Saline responsive (corrects volume contraction)

Saline unresponsive

Gastrointestinal Causes: Vomiting, NG suction, Chloride wasting diarrhea, Villous Adenoma

Renal Causes: Diuretic use, Carbenicillin, Penicillin, Sulfate, Phosphate, Post- hypercapnia

Exogenous Alkali: Sodium Bicarb, Sodium Citrate, Lactate, Gluconate, Acetate, Transfusion, Antacid

Cystic Fibrosis & Achlorhydria

Hypertensive Patient: Adrenal Disease: 1° Hyperaldosteronism, Cushing Syndrome, Liddle Syndrome

Hypertensive Patient: Exogenous Steroids: corticoids, licorice, carbenoxalone, glycyrrhizic acid, chewing tobacco

Normotensive Patient: Bartter or Gitelman Syndrome, Hypokalemia, Milk- alkali syndrome, Refeeding alkalosis, excessive alkali administration

Hallmark sign: increased bicarbonate level with rising PCO2

Shallow slow breathing, Anxiety and irritability, (+)Chvostek’s sign (+)Trousseau’s sign, decreased [K+] & [Ca+]; Paresthesias, muscle cramping and weakness; Tetany and seizures; Tachycardia, may be hypotensive, palpitations; increased bicarb & PCO2

Antiemetic medications; Monitor electrolytes and replace as indicated - Potassium sparing diuretic; Seizure Precautions

Lungs eliminate Too much of CO2

Increased Central Respiratory Drive: Anxiety, CNS infection, CVA, Brain tumor, Head trauma Medications: Salicylates, Nicotine, Aminophylline, progesterone, catecholamines, fever, sepsis, pregnancy, liver failure, hyperthyroidism

Increased Chemoreceptor Stimulation: Anemia, CO poisoning, pulmonary edema, pneumonia, PE, high altitude, restrictive lung disease

Iatrogenic: faulty settings with the mechanical ventilator

CNS, Hypotension, Excess mechanical ventilation, Atelectasis, Pain, Cirrhosis Hypermetabolic State, Insufficient, Oxygenation, Psychogenic, Salicylates/Sepsis

Rapid deep respirations, Anxiety and irritability, + Chvostek’s sign + Trousseau’s sign; decreased [K+] & [Ca+]; Paresthesia, muscle cramping and weakness; Tetany and seizures; Tachycardia, may be hypotensive, palpitations

Monitor ABGs periodically; Decrease respiratory rate: - focused breathing, decrease breaths per minute on ventilator settings, O2 therapy; Antianxiety medications

Acidemia

Alkalemia

For every increase in pCO2 of 10mm, pH decreases by .08

For every increase in pCO2 of 10mm, pH decreases by .03

For every decrease in pCO2 of 10mm, pH increases by .08

For every decrease in pCO2 of 10mm, pH increases by .03

Anion Gap normal

change in anion Gap (AG)

Corrected HCO3

If corrected HCO3 = 24

If corrected HCO3 = <24

If corrected HCO3 = >24