Respiratory System
Dr. SITESH Kr. SAH
RESPIRATORY SYSTEM: OVERVIEW
The respiratory system is the network of Tissues and Organs that help breathe.
Parts:
 Nose.
 Mouth.
 Throat (pharynx)
 Voice box (larynx)
 Windpipe (trachea)
 Airways (bronchi)
 Lungs.
Definition:
 Pneumonia is an inflammatory condition of the lung primarily affecting the small
air sacs known as alveoli.
 Symptoms typically include some combination of
 productive or dry cough,
 chest pain,
 fever, and
 difficulty breathing
PROGRESS OF INFECTION:
 Most of the time, the body filters organisms, and keeps the lungs healthy.
 But sometimes body fails to filter the organisms, It enter the lungs and cause infections.
• The microorganism reaches the lungs by:
—Inhalation or aspiration
—Hematogenious way
—Direct invasion from the neighbouring tissues
SEVERITY OF INFECTION:
 The amount of the organism inoculated,
 The virulance factors and
 The immunity of the host
Risk factors
 Pneumonia can affect anyone. But the two age groups at highest risk are:
1. Children who are 2 years old or younger
2. People who are age 65 or older
RISK FACTOR IN ADULT
 Being hospitalized: greater risk in a hospital intensive care unit, especially if on a ventilator.
 Chronic disease: more likely with asthma, chronic obstructive pulmonary disease (COPD) or
heart disease.
 Smoking. Smoking damages your body's natural defenses against the bacteria and viruses that
cause pneumonia.
 Weakened or suppressed immune system. People who have HIV/AIDS, who've had an organ
transplant, or who receive chemotherapy or long-term steroids are at risk.
 Alcohol : Daily alcohol consmption
 Corticosteroid therapy for Past 3 months
 Old age: Age >65 is at higher risk
RISK FACTOR IN CHILDREN
Classifications:
 CLINICAL CLASSIFICATION:
1.
Community-acquired: defined as pneumonia that is acquired outside the hospital.
 The most commonly identified pathogens are Streptococcus pneumoniae, Haemophilus influenzae,
atypical bacteria
2. Hospital-acquired: occurs during a hospital stay. This type of pneumonia can be very
severe. Sometimes, it can be fatal.
3. Aspiration pneumonia: occurs when food or liquid is breathed into the airways or lungs,
instead of being swallowed.
ANATOMICAL CLASSIFICATION :
1. Bronchopneumonia
2. Lobar pneumonia
3. Interstitial pneumonia
• ETIOLOGICAL CLASSIFICATION
1. Bacterial
2. Viral
3. Fungal
ANATOMICAL CLASSIFICATION
Bronchopneumonia affects the lungs in patches around bronchi (affects the
bronchi in the lungs)
Lobar pneumonia is an infection that only involves a single lobe, or section, of a
lung.
Interstitial pneumonia involves the areas in between the alveoli
Etiology:
Bacteria:
 Streptococcus pneumonia (50% Cases)
 Haemophilus influenzae (20% Cases)
 Chlamydophila pneumoniae (3% Cases)
 Mycoplasma pneumoniae (3% Cases)
ETIOLOGY
Viruses:
• In adults: one third of pneumonia cases, and
• In children: about 15%
Common agents :
 rhinoviruses, coronaviruses, influenza virus, respiratory
syncytial virus (RSV), adenovirus, and parainfluenza.
 Notes: organ transplantation and immunocompromised
persons,: cytomegalovirus pneumonia.
Fungus:
• Fungal pneumonia is uncommon,
• Occurs commonly in weakened immune systems due to
AIDS, immunosuppressive drugs, or other medical
problems.
Common agents:
 Histoplasma capsulatum, Blastomyces, Cryptococcus
neoformans, Pneumocystis jiroveci (pneumocystis
pneumonia, or PCP), and Coccidioides immitis
Diagnosis:
 Medical history:
 Physical exam:
 Laboratory investigation:
 Radiological investigation:
 Others investigation:
CLINICAL EVALUATION: MEDICAL HISTORY
Fever, sweating and shaking chills
Cough, which may produce greenish, yellow or even bloody mucus
Shortness of breath
Rapid, shallow breathing
Other Clinical Manifestation:
The signs and symptoms of pneumonia may include:
 Sharp or stabbing chest pain that gets worse when you breathe deeply or cough
 Loss of appetite, low energy, and fatigue
 Nausea and vomiting, especially in small children
 Confusion, especially in older people
PHYSICAL EXAMINATION:
GENERAL EXAM:
• High fever,
• Tachicardia,
• Tachypnea,
• Hypotension,
• Confusion,
• Drowsiness,
• Altered mental status
• Cyanosis
RESPIRATORY SYSTEM:
• Inspection:
— Usually normal
— Ortopnea
— Respiratory disstress
• Palpation
— increased Vibration thoracic (lober pneumonia)
— Decreased hemithoracal movement
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Percution
— Normal sonority
— Dullness (Matite)
Oscultation
— End inspiratory fine crackles
— Local diminished breath sounds
— Bronchial voice
Laboratory investigation
 Complete Blood Count:
 Arterial Blood Gasses.
 Blood Culture.
 Pleural fluid culture
Sputum Tests.
 Gram Staining (A Gram stain is a test that checks for bacteria at the site of a suspected
infection such as the throat, lungs, genitals, or in skin wounds. Gram stains may also be used
to check for bacteria in certain body fluids, such as blood or urine.
 AFB (acid-fast bacillus) a type of bacteria that causes tuberculosis and certain other infections.
 Giemsa or methenamine silver stain
 KOH (potassium hydroxide) mount (Presence of Fungus)
RADIOLOGICAL EXAMINATION:
X-ray: SUGGESTIVE FEATURE OF BACTERIAL LRI
SUGGESTIVE FEATURE OF VIRAL LRI
OTHERS INVESTIGATION:
 Pulse Oximetry:
 CT Scan.
 Bronchoscopy
 Thoracoscopy
 Percutaneous aspiration/biopsy
 Open lung biopsy
GENERAL MANAGEMENT
AT HOME
 FEVER: Treat with aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen
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or naproxen), or acetaminophen. DO NOT give aspirin to children.
Drink plenty of fluids to help loosen secretions and bring up phlegm.
Do not take cough medicines : Coughing is one way your body works to get rid of an
infection, UNLESS cough is preventing you from getting the rest you need.
Drink warm beverages: take steamy baths and use a humidifier to help open your airways
and ease your breathing.
Stay away from smoke: Let your lungs heal. This includes smoking, secondhand smoke and
wood smoke. This would be a good time to think about quitting for good.
Get lots of rest:You may need to stay in bed for a while. Get as much help as you can with
meal preparation and household works until you are feeling stronger.
AT HOSPITAL: OPD /ER
SEVERITY ASSESSMENT
In child
In old age
20 mg/dL
>30 breaths
<90/60
CURB 65
 C onfusion – Altered mental status
 U remia – Blood urea nitrogen (BUN) level greater than 20 mg/dL
 R espiratory rate –30 breaths or more per minute
 B lood pressure – Systolic pressure less than 90 mm Hg or diastolic pressure less than 60
mm Hg
 Age older than 65 years
Score evaluation and treatment :
 Score of 0-1 – Outpatient treatment
 Score of 2 – Admission to hospital(No ICU)
 Score of 3 or higher – Admission to intensive care unit (ICU)
Outpatient Treatment:
 Outpatients Treatment(empirical): For
 MILD Pneumonia and CURB 65 Score of 1
 Previously healthy and no antibiotics in past 3 months : Treat for 7days
 AMOXICILLIN – 1 gm TDS Plus MACROLIDE (clarithromycin 500
mg BID) OR
 Respiratory FLUOROQUINOLONES [moxifloxacin ,levofloxacin ] OR
 DOXYCYCLINE 200 Mg STAT then 100 Mg BID
 Comorbidities or antibiotics in past 3 months:
 AMOXICILLIN – 1 gm TDS / AUGMENTIN 625 Mg- TDS Plus MACROLIDE
(clarithromycin 500 mg BID/ Azithromycin- 500 Mg OD)
 Respiratory FLUOROQUINOLONES [moxifloxacin 400 Mg OD
,levofloxacin 750 Mg OD ]
MILD PNEUMONIA
INDICATION FOR ADMISSION
, Severe Pneumonia in children And CURB 65 Score of 2 in older
Inpatients, Non- ICU
 IV fluoroquinolone [moxifloxacin-400 mg OD ,levofloxacin- 750 Mg OD] OR
 IV AMOXICILLIN or AUGMENTIN plus
 a macrolide [IV clarithromycin or azithromycin)
Inpatients, ICU
• IV β -lactam (ceftriaxone – 1 gm BID ) plus
• IV Azithromycin OR
• IV fluoroquinolone
Pseudomonas
 IV β-lactam [piperacillin/tazobactam OR cefepime )plus
 IV flouroquinolons [levofloxacin -750 mg IV OD ]
Methicillin-resistant Staphylococcus aureus (MRSA)
 add linezolid or vancomycin
 ASSPIRATION PNEUMONIA:
 IV CLINDAMYCIN 600 Mg TID OR
 IV CEFTRIAXONE 1 gm OD plus
 METRONIDAZOLE 500 Mg QID OR
 PIPERACILLINE-TAZOBACTUM 4.5 Gm QID
EMPHYEMA:
 IV- CLINDAMYCIN 600 Mg TID Plus
 CEFTRIAXONE 1 gm OD OR
 CEFEPIME 2 Gm BID
 IV CEFTRIAXONE 1 gm OD plus
 METRONIDAZOLE 500 Mg QID/1 Gm BID OR
 PIPERACILLINE-TAZOBACTUM 4.5 Gm QID
Complications:
 Bacteria in the bloodstream (bacteremia). Bacteria that enter the bloodstream from your
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lungs can spread the infection to other organs, potentially causing organ failure.
Difficulty breathing. If your pneumonia is severe or you have chronic underlying lung diseases,
you may have trouble breathing in enough oxygen.You may need to be hospitalized and use a
ventilator while your lung heals.
Fluid accumulation around the lungs (pleural effusion). Pneumonia may cause fluid to
build up in the thin space between layers of tissue that line the lungs and chest cavity (pleura). If
the fluid becomes infected, you may need to have it drained through a chest tube or removed with
surgery.
Lung abscess. An abscess occurs if pus forms in a cavity in the lung. An abscess is usually treated
with antibiotics. Sometimes, surgery or drainage with a long needle or tube placed into the
abscess is needed to remove the pus.
Pleurisy.
Septic arthritis.
Endocarditis.