Principles of Practice

Organs of the Respiratory System

  • Nasal cavity, pharynx, trachea, external nares, oral cavity, apex of left lung, right primary bronchus, larynx, diaphragm, base of left lung.

Unit Objectives:

  • Revise anatomy and physiology of respiration.

  • Revise subjective and objective chest assessment principles, components, and techniques.

  • Review respiratory symptoms and clinical signs.

  • Review patterns of breathing.

Nasal Cavity

  • Filters and removes large particles.

  • Moistens and warms the air.

Mucocilliary Escalator

  • Mucus blanket traps small particles and moves them upwards to be expectorated.

  • Impaired by dehydration, smoking, inflammation, and respiratory conditions affecting mucus viscosity.

Lung Landmarks

  • Apices extend above clavicles.

  • Horizontal fissure follows right 4th rib.

  • Oblique fissures extend to 6th rib anteriorly.

  • Left lung has a large deficit anteriorly (4th to 6th rib).

  • Lungs extend to 8th rib laterally.

  • Parietal pleura extends to 9th rib laterally.

Posterior Lung

  • Upper portions covered by scapulae.

  • Oblique fissures extend from spinous processes of T2.

  • Lungs extend down to T11 medially and 9th rib laterally.

Surface Markings

  • Oblique Fissure: Divides Upper and Middle lobes from Lower lobes, runs from T2 to the 6th Costal Cartilage anteriorly.

  • Horizontal Fissure: Divides Upper lobe from Middle lobe, runs from 4th intercostal space at the right sternal edge to mid-axillary line where it joins oblique fissure.

Diaphragm

  • 6th rib anteriorly, 8th rib in mid-axillary line, and 10th rib posteriorly.

  • Apical segments extend 2.5cm above the clavicles.

Pleura

  • Visceral pleura lines the outer surface of the lung.

  • Parietal pleura lines the inside of the thoracic cavity.

  • Pleural Cavity: space between visceral and parietal pleura with a small amount of fluid between them.

Lung Volumes

  • Tidal volume (TV): volume of air moved in and out during each ventilatory cycle.

  • Inspiratory reserve volume (IRV): additional volume of air that can be forcibly inhaled.

  • Expiratory reserve volume (ERV): additional volume of air that can be forcibly exhaled.

  • Vital capacity (VC): maximal amount of air expelled after maximal inspiration; ERV+TV+IRVERV+TV+IRV.

  • Residual volume (RV): volume of air remaining after maximal expiration; FRC−ERVFRC - ERV.

  • Functional residual capacity (FRC): volume of air remaining at the end of normal expiration; RV+ERVRV + ERV.

  • Total lung capacity (TLC): volume of air at the end of maximal inspiration; FRC+TV+IRV=VC+RVFRC + TV + IRV = VC + RV

  • FeV1FeV1: volume exhaled during the first second of forced expiration from TLC.

  • FVC: amount of air forcibly exhaled from the lungs from TLC.

  • Minute volume: volume of air exhaled per minute.

  • Dead space volume: air in the conducting zone that never reaches alveoli.

Physiology of Breathing

  • Inhalation: governed by Boyles law (pressure inversely proportional to volume).

  • Inspiration: Thoracic cavity volume increases, and air is drawn in due to diaphragm and intercostal muscle contraction.

Expiration

  • Passive due to elastic recoil of the lung.

  • Diaphragm relaxes, ribs drop, decreasing thoracic volume and increasing intrathoracic pressure.

Assessment

  • Accurate assessment is the basis of good practice.

  • Background information: nurses reports, medical notes.

  • Start with good rapport with nurse, doctor, and MDT.

  • Communication skills: elicit sound information.

Medical Notes

  • Medical history: past and present.

  • Allergies.

  • Social history: smoking history

  • Relevant investigations.

  • Response to previous treatment.

  • Possibility of bony metastases.

  • Long-standing steroid therapy.

Haematology

  • A FBC assesses blood cells and coagulation.

  • Hb: Protein that carries oxygen; low Hb indicates anaemia (12-14 females, 14-18 males).

  • White blood cells: High/low (7-11).

  • INR (1).

Blood Chemistry

  • Electrolytes such as Na+,K+,Cl−Na^+, K^+, Cl^-.

  • Sodium: regulates water and acid-base balance.

  • Low serum Sodium (Na+): hyponatremia due to excess water or inappropriate ADH.

  • High serum Sodium (Na+): hypernatremia.

  • Potassium: critical for nerve and muscle function, including cardiac muscles.

Potassium Levels

  • Potassium levels can impair diaphragmatic contraction if raised or lowered.

  • Decreased serum Potassium (K+): hypokalemia predisposes to cardiac arrhythmia.

  • Increased serum Potassium (K+): hyperkalemia may suggest kidney failure.

  • Chloride: maintains acid-base balance and cellular integrity (Normal range 97-107 mEq/L).

Causes of Hypocloremia

  • Decreased serum Chloride (Cl-): hypochloremia caused by vomiting, diarrhea, sweating, or high fevers.

  • Drugs such as: bicarbonate, corticosteroids, diuretics, and laxatives.

Increased Cloride

  • Increased Cloride (Cl-): hyperchloremia in the sweat can be diagnostic of cystic fibrosis.

  • Urea levels: High urea levels indicate kidney failure.

  • Creatinine levels: Levels rise with kidney failure (Males: 0.6-1.2 mg/dL, Females: 0.5-1.1mg/dL).

Observation Charts

  • Temperature: (36-37.5) degrees Celsius. Oral-37 degrees celsius on average. Rectal- 0.3-0.6 degrees higher than oral. Axillary-0.3-06 degrees lower than oral.

  • HR: 60-100 bpm.

  • BP: 95/60-140/90.

Respiratory Symptoms

  • Wheeze

  • Chest Pain

  • Breathlessness

  • Cough

Wheeze

  • Caused by airflow forced through narrowed airways, increases WOB.

  • Musical with bronchospasm and noisy with retained secretions.

  • The presence of Inspiratory and expiratory wheeze - may indicate severe airway narrowing and copious of secretions.

Chest Pain

  • Musculoskeletal, cardiac, alimentary or respiratory.

  • Sharp stabbing pain worse on deep breathing + extreme tenderness on palpation + deep breathing gives localized pain = fractured rib.

Origins of Chest Pain

  • Cardiac: Angina Pectoris: crushing/suffocating, exertion-related.

  • Musculoskeletal: muscular strain due to excessive coughing.

  • Pulmonary: pleuritic (sharp stabbing) pain aggravated by breathing, pneumonia/ PE/pneumothorax.

Breathlessness

  • Cardiovascular, metabolic, neurogenic, neuromuscular or respiratory.

  • Ability/Inability to walk or talk indicates resp breathlessness.

Modified Borg Scale

  • Measures breathlessness (0-10; Nothing at All to MAXIMAL).

Breathlessness

  • May be cardiovascular, metabolic, neurogenic, neuromuscular, or respiratory.

  • Significant respiratory breathlessness is indicated by a need to pause during talking or undressing, or an inability to walk and talk at the same time.

Types of Breathlessness

  • Orthopnoea: Blood pools in pulmonary circuit caused by a poorly functional left ventricle. On lying there is increased venous return and redistribution of stored blood within the pulmonary vascular beds. This may lead to pulmonary oedema and poor gas exchange

  • Paroxysmal Nocturnal Dyspnoea: Orthopnoeic patients slide off pillows at night because of breathlessness.

Questions about Cough

  • Details surrounding the onset of the cough.

  • Sputum characteristics: amount and quality.

  • Changes in cough: nocturnal occurrences.

Type of Cough

*Dry: Asthma, interstitial lung disease
*Productive: COPD, bronchiectasis
*On position change: GOR, asthma, bronchiectasis

Sputum

  • Expectorated mucous from the respiratory tract.

  • Hemoptysis: expectoration of sputum containing blood.

  • Bright red: fresh; pink: mixed with sputum; rusty brown: old.

  • Blood clotting abnormality, trauma (Pulmonary Embolus

Other Clues

  • Early morning headaches (CO2 retention).

  • Rapid body weight reduction (advanced cancer).

  • Night sweats (TB).
    Blood clotting abnormality.

Observation

*COMFORT, COLOUR, SIZE, POSITION,POSTURE, APPARATUS

  • Observation begins as you walk into the room, even before an introduction.

  • Posture indicates pain, fatigue, respiratory distress?

  • Unkempt indicates disease-related challenges with self-care?
    Restlessness indicates that pt is hypoxic.

Observations Continue

  • Pallor: anaemia, decreased cardiac output, hypovolemic shock.

  • Cyanosis: unsaturated hemoglobin due to respiratory/circulatory disorders.

Hands

  • Cold: poor CO.

  • Warm: CO2 retention.

  • Fine tremor: bronchodilator use.

  • Nicotine stains: smoking history.

  • Clubbing: pulmonary, cardiac, liver, or gut causes.

Chest Shape and Breathing

  • Rigid barrel chest (chronic lung disease).

  • Chest wall abnormalities increase WOB.

  • Kyphotic curvatures increase respiratory failure risk.

  • Pectus carinatum and excavatum.

  • Breathing pattern:

    • normal rhythmic breathing

    • labored breathing (accessory muscle contraction, nasal flaring, rapid RR), ratio of insp exp is 1:2

Paradoxical Chest

    Pulling in of lower ribs during  inspiration because of a flattened diagram, breathing pattern

Breathing Patterns

  • Cheyne-Stokes respirations: shallow-deep-shallow pattern with apnea.

  • Biot’s breathing (cluster respiration): rapid respirations of near equal depth followed by apnea.

  • Kussmaul’s respirations: deep and rapid respiratory pattern associated with severe metabolic acidosis.

  • Ataxic respirations: Irregular pattern with pauses and increasing episodes of apnea. Caused by damage to the medulla Oblongata with a poor prognosis
    Apneustic breathing: has a prolonged inspiratory phase followed by a prolonged expiratory phase

Palpation

  • Chest expansion.

  • Crackling of sputum or surgical emphysema.

Fremitus and Circulation

  • Tactile vocal fremitus: palpation for voice vibration.

  • Good circulation: Capillary refill less than 3 seconds.

Burns Definitions

  • Caused by acute exposures (heat, cold, electricity, or caustic chemicals).

The skin has Epidermis and Dermis

The Epidermis :

  • Keratinocytes, melanocytes
    Dermis :

  • Collagen fibrils, elastic fibres, nerve endings, hair follicles, sweat glands lymphatic and blood vessels.

Classification of Burns

  • By depth of tissue injury and extent of the burns

    • Superficial (1e)

    • Partial thickness (2e)

    • Full thickness (3e)

    • % of TBSA (total body surface Area)

Superficial Burns

  • Involve only the epidermis layer.

    • Signs: No blisters, Dry, Painful, Red, Blanch with pressure.
      Partial thickness Burns (both Epidermis and portions of the dermis).

  • Superficial partial thickness: Blisters appear, very Painful, Heal within a short amount of time without function impairment

Surgical Management

  • Surgery:

    • Debridement: Autolytic or Surgical

    • Escharotomy or Fasciotomy

    • Wound management using Skin graft allograft. NO movement for 5 days over grafted area

Burn shock happens, there will be Capillary permeability increases

Peripheral Vasoconstriction happens

Metabolic Responses

  • Hyper-catabolism

  • Increased osteoclastic-activity (increase risk of fractures).

Causes for burns

  • Children, women, elerly, fraity and con-morbid illnesses of elderly parental illiteracy.
    Ignition of clothing.

Types of Burning

*Thermal, checmical, electrical, inhalation etc….