Lung Sounds
An Assessment of the Patient in Respiratory Distress
Michael Ciccarelli, DO December 12, 2006
Introduction
• Lungs major function
– Provide continuous gas exchange between inspired air and blood in the pulmonary circulation
Anatomy of Respiratory System
• • • • • • Nasopharynx Larynx Trachea Bronchi Bronchioles Alveoli
Anatomy
• Respiratory tract extends from mouth/nose to alveoli • Upper airway filters airborne particles, humidifies and warms inspired gases • Lower airway serves for gas exchange
Anatomy
Blood Supply
• Lungs have a double blood supply
– Pulmonary circulation for gas exchange with the alveoli (pulmonary artery with subdivisions) – Bronchial arteries arising from descending aorta supplies lung parenchyma
Contributors of Respiration
• Controlled in the brainstem • Mediated by muscles of respiration
– Diaphragm primary muscle of inspiration – Accessory muscles of inspiration
• SCM • Scalenes • Intercostals
• Expiration is a passive process from elastic recoil of lung and chest wall, with passive diaphragm relaxation
Mechanism for Breathing
• Pressure gradient required to generate air flow
– Diaphragm contracts, descends and enlarges thoracic cavity – Intra-thoracic pressure decreases – Air flows through tracheobronchial tree into the alveoli expanding lungs
Technique for Respiratory Exam
• NEED ORDERLY PROCESS • Before beginning, if possible:
– Quiet environment – Proper positioning (patient sitting for posterior thorax exam, supine for anterior thorax exam) – Bare skin for auscultation – Patient comfort, warm hands and diaphragm of stethoscope, be considerate of women (drape sheet to cover chest)
• • • •
Inspect Palpate Percuss Auscultate
Initial Respiratory Survey
• Observe the patient’s breathing pattern
– Rate (normal vs. increased/decreased) – Depth (shallow vs. deep) – Effort (any sign of accessory muscle use, inspect neck)
• Assess the patient’s color
– cyanosis
Normal Respiratory Rates
– Infant 30-60 – Toddler 24-40 – Preschooler 22-34 – School-age child 18-30 – Adolescent 12-16 – Adult 10-20
Pertinent History
– Any chronic conditions
• Asthma, COPD, CHF, DM
– Exposure to new medication
• ACE-Inhibitor, Abx
– Recent change in diet
• Peanuts, Strawberries
– Substance abuse/Overdose
• Opioid abuse, ASA toxicity
– Prior DVT, PE – Recent trauma to chest
Inspection
• Note the shape of the chest and the way it moves
– Deformities or asymmetry
• Increased AP diameter in COPD
– Abnormal retractions of interspaces during respiration
• Lower interspaces, supraclavicular in acute asthma exacerbation
– Impaired respiratory movement
• Flail Chest and paradoxical movement with rib fx’s
Palpation
• Identify tender areas
– Bruising with rib fx
• Observe for appropriate chest wall expansion • Feel for tactile fremitus symmetrically
– palpable vibrations transmitted to chest wall – use ulnar surface of hand, say “ninety-nine” – decreased with COPD, pleural effusions, PTX
Percussion
• Helps to identify if underlying tissues are air-filled, fluid-filled, or solid
– Hyperextend middle finger of either hand and press against chest wall – Strike with flexed middle finger of opposite hand
• Always percuss symmetrically on chest wall
Percussion Notes
• Flatness
– Thigh
• Dullness
– Liver
• Resonance
– Lung
• Hyperresonance
– None
• Tympany
– Stomach, puffed cheek
Percussion
• Dullness replaces resonance when fluid or solid tissue replaces air containing lung
– – – – PNA Pleural Effusions Hemothorax Tumor
• Unilateral Hyperresonance
– Pneumothorax
• Generalized Hyperresonance
– COPD
Auscultation
• • • • 12 anterior locations 14 posterior locations Auscultate symmetrically Should listen to at least 6 locations anteriorly and posteriorly
Breath Sounds
• Normal
– – – – Tracheal Bronchial Bronchovesicular Vesicular
• Adventitious
– – – – – Crackles (Rales) Wheeze Rhonchi Stridor Pleural Rub
• Abnormal
– Absent/Decreased – Bronchial
Normal Breath Sounds
• Created by turbulent air flow • Inspiration
– Air moves to smaller airways hitting walls – More turbulence, Increased sound
• Expiration
– Air moves toward larger airways – Less turbulence, Decreased sound
• Normal breath sounds
– Loudest during inspiration, softest during expiration
Normal Breath Sounds
• Tracheal
– Very loud, high pitched sound – Inspiratory = Expiratory sound duration – Heard over trachea
• Bronchial
– – – – Loud, high pitched sound Expiratory sounds > Inspiratory sounds Heard over manubrium of sternum If heard in any other location suggestive of consolidation
Normal Breath Sounds
• Bronchovesicular
– Intermediate intensity, intermediate pitch – Inspiratory = Expiratory sound duration – Heard best 1st and 2nd ICS anteriorly, and between scapula posteriorly – If heard in any other location suggestive of consolidation
• Vesicular
– Soft, low pitched sound – Inspiratory > Expiratory sounds – Major normal BS, heard over most of lungs
Transmitted Voice Sounds
• If abnormally located bronchial or bronchovesicular breath sounds assess transmitted voice sounds with stethoscope
– Ask the patient to say “Ninety-nine”, should normally be muffled, if heard louder and clearer this is bronchophony – Ask the patient to say “ee”, should normally hear muffled long E sound, if E to A change this is egophony – Ask the patient to whisper “Ninety-nine”, should normally hear faint muffled sound, if louder and clearer sounds are heard this is whispered pectoriloquy
• Increased transmission of voice sounds suggests that air filled lung has become airless
Adventitious Breath Sounds
• Crackles (Rales)
– – – – Discontinuous, intermittent, nonmusical, brief sounds Heard more commonly with inspiration Classified as fine or coarse Normal at anterior lung bases
• Maximal expiration • Prolonged recumbency
– Crackles caused by air moving through secretions and collapsed alveoli – Associated conditions
• pulmonary edema, early CHF, PNA
Adventitious Breath Sounds
• Wheeze
– Continuous, high pitched, musical sound, longer than crackles – Hissing quality, heard > with expiration, however, can be heard on inspiration – Produced when air flows through narrowed airways – Associated conditions
• asthma, COPD
Adventitious Breath Sounds
• Rhonchi
– Similar to wheezes – Low pitched, snoring quality, continuous, musical sounds – Implies obstruction of larger airways by secretions – Associated condition
• acute bronchitis
Adventitious Breath Sounds
• Stridor
– Inspiratory musical wheeze – Loudest over trachea – Suggests obstructed trachea or larynx – Medical emergency requiring immediate attention – Associated condition
• inhaled foreign body
Adventitious Breath Sounds
• Pleural Rub
– Discontinuous or continuous brushing sounds – Heard during both inspiratory and expiratory phases – Occurs when pleural surfaces are inflamed and rub against each other – Associated conditions
• pleural effusion, PTX
Causes of decreased or absent breath sounds
• • • • • • Asthma COPD Pleural Effusion Pneumothorax ARDS Atelectasis
Case #1
• Dispatch Information
– 62 yo female with progressive SOB over past 48 hours
• PMH
– 40 pack year smoking history – On home O2 – Some type of lung problem
• VS
– O2 sat 78% on 2L O2 NC, RR 26, T 98.1
• Physical Exam
– – – – Barrel shaped chest Decreased BS B/L Diffuse expiratory wheezing B/L lung fields Digital cyanosis and clubbing noted
What is this patient’s condition and appropriate treatment prior to ED arrival?
Case #2
• • Dispatch Information
– 18 yo male with confusion and multiple episodes of vomiting
PMH
– No past medical history – Denies recent drug use or overdose
•
•
VS
– T 98.3, RR 32, HR 116, O2 sat 98% RA
Physical Exam
– – – – Appears Lethargic Dry Mucous Membranes Deep, rapid breathing Lungs CTA B/L
•
Additional Findings
– FS 450
What is this patient’s condition and appropriate treatment prior to ED arrival?
Case #3
• • Dispatch Information
– 74 yo male with progressive SOB over past week
PMH
– – – – Poor historian, no family available for information Difficult time sleeping on 4 pillows States sees a heart doctor, however, not taking pills At house full bottles of Coreg, Lisinopril, and Lasix
• •
VS
– RR 30, O2 sat 82% RA, T 98.4
Physical Exam
– – – – Rapid, shallow breathing Accessory muscles of respiration use Crackles are auscultated at B/L bases B/L LE pitting edema to knees
What is this patient’s condition and appropriate treatment prior to ED arrival?
Case #4
• Dispatch Information
– MVA rollover on Rt. 4 in East Greenbush
• • • • 25 yo male unrestrained driver significant intrusion into driver door + LOC, GCS 13 at present
• PMH
– EtOH abuse
• VS
– RR 28, O2 sat 76% RA
• Physical Exam
– multiple bruises on B/L chest wall – paradoxical movement of L chest wall – absent breath sounds on L side
What is this patient’s condition and appropriate treatment prior to ED arrival?
Case #5
• Dispatch Information
– 42 yo female with difficulty breathing and facial swelling over past hour
• PMH
– HTN – NKDA or food allergies – Started Lisinopril for BP 1 month ago
• VS
– HR 108, RR 28, O2 sat 86% RA, T 98.4
• Physical Exam
– Perioral facial and lip swelling – Inspiratory stridor on auscultation
What is this patient’s condition and appropriate treatment prior to ED arrival?