Lecture Respiratory Insufficiency_i

RESPIRATORY INSUFFICIENCY IN CHILDREN

Case 1 • Girl, 6 months • Previous healthy • History – Start with coryza since 2 days – Now since 1 day cough and wheeze

Physical exam • • • • •

Body weight 6 kg Temp: 38.2 °C, Respiratory rate 50-60/min No chest indrawing No nasal flaring Auscultation – Some crackles – Expiratory wheezing

Question The most likely diagnosis is 3. 4. 5. 6.

Bronchiolitis due to Respiratory Syncytial Virus Bacterial pneumonia Secondary pneumonia after viral infection Asthma

Semin Pediatr Infect Dis 2005;16:84-92

Question A. B.

5. 6. 7. 8.

Expiratory wheezing indicates a lower (intra-thoracal) airway obstruction (i.e. the bronchioli) Inspiratory stridor indicates a higher (extra-thoracal) airway obstruction (i.e. the trachea) Only A is true Only B is true A and B are true A and B are false

Intra-thoracal obstruction

+ + + -

-

-

Ptr > Ppl

+

-

-

-

- Ptr

+ > Ppl

-

-

Inspiration

+

+

+

+

Ptr < Ppl

+

+ Expiration

+

Extra-thoracal obstruction + -

Ptr < Patm

+

Ptr > Patm

+

-

-

+ -

Inspiration

+ +

+ Expiration

Question A.

Expiratory wheezing indicates a lower intra-thoracal airway obstruction. Asthma, bronchiolitis

•

Inspiratory stridor indicates a higher extra-thoracal airway obstruction (i.e. the trachea). Laryngitis subglottica, corpus alienum

• • • •

Only A is true Only B is true A and B are true A and B are false

Case 2 • Boy, 4 yrs old • Always healthy, no chronic diseases • History: since 2 days fever and cough

Physical exam • • • •

Temperature 39.5 °C Respiratory rate: 55/min, pulse rate 120/min Nasal flaring Chest indrawing

• Auscultation: crepitations right hemithorax

Question A. Chest indrawing represent accessory respiratory muscles use B. Chest indrawing is more common in children than in adults 5. 6. 7. 8.

A is true B is true A and B are true A and B are false

Question A. Respiratory rate of 55/min is normal in children B. Pulse rate of 120/min is to high in children 5. 6. 7. 8.

A is true B is true A and B are true A and B are false

Normal values vital signs children Age

Pulse rate

Bloodpressure

Resp. rate

Newborn

120-160

60/40

40-50

1 month -2 year

80-140

85/55

30-40

2-5 year

70-115

90/60

20-30

5-8 year

70-115

100/65

15-25

>8 year

70-110

110/70

12-20

Note 1: normal pulse rate in case of fever: for every degree temperature above 37.5 increase pulse rate with 10/min Note 2: Rule of thumb for bloodpressure: systolic bloodpressure= (2*age)+85

Case continued • Differential diagnosis – Bronchitis – Bronchiolitis – Pneumonia

• Treatment – Amoxicillin 125mg tds

Question Among the most frequent bacterial causes of acute respiratory tract infections in children are: 1. 2. 3. 4.

Streptococcus pneumoniae Haemophilus Influenzae Staphylococcus Aureus All of the above

Semin Pediatr Infect Dis 2005;16:84-92

MSFH Guidelines respiratory tract infection Chest indrawing No

Yes

Respiratory rate increased

Severe pneumonia

No No pneumonia

Yes < 2 m: >60/min 2 m-1y: >50/min 1-5 y: >40/min

Pneumonia

Question A.

Mortality rate due to pneumonia decreases when antibiotics are given promptly

B.

Malnutrition is a risk factor for mortality due to pneumonia

7. 8. 9. 10.

A is true B is true A and B are true A and B are false

Meta-analysis of intervention trials on case-management of pneumonia in community settings Sazawal et al. Lancet 1992; 340: 528 33

• Meta analysis of 6 intervention trials • Intervention: active case management (including antibiotics) by community health workers based on simple algorythm • Results: 35% reduction in mortality rate <5 years of life.

Case continued History/ Mother returns to the clinic with the boy after one day because of no improvement Physical Exam/ Temp 39 °C, resp rate: 50/min, pulse rate 150/min Chest retractions Lips and tongue cyanotic

Question There are 2 forms of cyanosis: central cyanosis and peripheral cyanosis What is the pathophysiological difference?

Cyanosis • Central cyanosis: arterial oxygen desaturation – Alarm sign! – Sign of severe respiratory insufficiency!

• Peripheral cyanosis: venous oxygen desaturation – Not necessarily alarm – Centralisation of bloodflow

Question What could have been the reason for treatment failure? 4. Micro-organism resistant 5. Not taking amoxicillin appropriately 6. Dosage of amoxicillin

•

Streptococcal resistance against β-lactam antibiotics occurs through β-lactamase production

•

It makes sense to increase the dose of β-lactam antibiotics in case of suspicion of H Influenza resistance

6. 7. 8. 9.

A is true B is true A and B are true A and B are false

Resistance against β-lactam antibiotics • Streptococci: – change in Penicillin Binding Protein – In general this is dose dependent

• H Influenzae – β-lactamase production

Drug resistance among S pneumoniae in SE Asia • Most studies: penicillin resistance patterns • Prevalence of SP Penicillin resistance up to 40% • Critchley 2002, Reechaipichitkul 2006, Watanabe 2003

• Penicillin resistant SP: variable sensitivity to amino-penicillin (i.e. amoxicillin) : 50-95% • Critchley 2002, Srifeungfung S 2005, Reechaipichitkul 2006

Drug resistance among H Influenzae in SE Asia • Prevalence of beta-lactamase producing H.I. highly variable: 20-57% – Phan 2006, Critchley 2002, Larson 2000

• Amoxicillin-clavulanic acid potential alternative

Circulatory insufficiency in children Recognition and first treatment

Case 1 • Boy, 2 year – Previous history no abnormalities – Since 3 days severe diarrhoea, with more than 5 watery stools/day – Poor drinking

Physical exam • • • • • •

Alert Pulse rate: 180/min Bloodpressure: 90/45 mm Hg Respiratory rate: 25/min Poor turgor, capillary refill > 3 sec Cold extremities

Is this patient in shock? A. Yes, pulse rate is high, skin turgor is poor and capillary refill is prolonged C. No the bloodpressure is still ok

Case 2 • Girl, 3 yrs • Previous healthy • Since 4 days coryza and skin rash • Since 1 day more sick and high fever

Physical exam • • • • • •

Not alert Temperature: 38.5 °C Pulse rate: 150 /min Bloodpressure: 60/40 mm Hg Respiratory rate: 55/min Skin lesions with secundary infection

Is this patient in shock? A. Yes, organ perfusion and thus function is decreased B. No, the diastolic bloodpressure is still ok

What is shock? A. Shock is a situation in which perfusion of the organs is acutely decreased and oxygen supply can not fulfill oxygen demand C. Shock is a situation of increased pulse rate and low diastolic bloodpressure

Shock Pathophysiology • Cardiogenic shock • Distributive shock • Hypovolaemic shock

Imminent shock compensation mechanisms 1. Increase of cardiac output: Increase of pulse rate in children 4. Centralisation of the bloodflow Cold hands and feet 3. Increase of oxygen extraction Peripheral cyanosis

Shock Compensation mechanisms insufficient • Bloodpressure decreases – bloodpressure is a late (preterminal) sign

• Perfusion of organs to low: – Brain: decreased consciousness – Kidney: decreased urine output – Lungs: increased respiratory rate

Back to the 2 patients Case 1, ♂ 2 y

Case 2, ♀ 3 y

• • • • • • •

• • • • • •

Alert Pulse rate: 180/min Bloodpressure: 90/45 mm Hg Respiratory rate: 25/min Poor turgor capillary refill > 3 sec Cold extremities

Not alert Temperature: 38.5 °C Pulse rate: 150 /min Bloodpressure: 60/40 mm Hg Respiratory rate: 55/min Skin lesions with secundary infection

Why so much attention to this?

Treatment of shock in children • Early goal directed therapy! • The first hours are most important • Early antibiotics: better survival

• Goal of the study: – Does Early Goal Directed treatment make sense?

• Intervention – ‘Aggressive’ early volume expansion vs ‘normal’ volume expansion

Early goal directed therapy consequences for MSFH setting Before sending to hospital: • If possible: give iv line and start iv fluid bolus • Give first dose of parenteral broad spectrum antibiotics • If possible: accompagny patient to hospital

How much fluid for the child in shock? 1. 20 ml/kg in 30 minutes 2. 5 ml/kg in 2 h