pediatric pneumonia感染小儿肺炎课件

Infectious Pediatric Pneumonia Author: Roberta D. Hood, HBSc, MD, CCFP Lecturer, University of Toronto Date Created: December 2011 Learning Objectives o To describe the presentation of pediatric pneumonia o To outline the management of pediatric pneumonia o To summarize the complications of pediatric pneumonia o To highlight interventions to prevent and protect against pediatric pneumonia Outline oQuiz oEpidemiology and Pathophysiology oPatient History oPresentation and Diagnosis oManagement and Disposition oFurther Testing oComplications oTreatment oInterventions to Protect oInterventions to Prevent oSummary Key Points oCase oQuiz Results Quiz Question 1 What illness is the number one killer of children? o A. Diarrheal Disease o B. HIV/AIDS o C. Malaria o D. Pneumonia Quiz Question 2 What is the most sensitive and specific sign of pneumonia in children? o A. Difficulty breathing o B. Fever o C. Tachypnea o D. Tachycardia Quiz Question 3 If available, a chest x-ray should be done for children with possible pneumonia: o A. When a diagnosis is made o B. When a history of tachypnea is present o C. When antibiotics are started o D. When complications are suspected Quiz Question 4 Which of the following immunization effectively reduce pneumonia mortality in children? o A. Haemophilus influenzae b Vaccine o B. Pneumococcal Conjugate Vaccine o C. Measles Vaccine o D. All of the above What is Pneumonia? o Pneumonia: an acute infection of the pulmonary parenchyma o The term “Lower Respiratory Tract Infection” (LRTI) may include pneumonia, bronchiolitis and/or bronchitis Epidemiology and Pathophysiology Epidemiology o Pneumonia kills more children under the age of five than any other illness in every region of the world. o It is estimated that of the 9 million child deaths in 2007, 20% (1.8 million) were due to pneumonia o Approximately 98% of children who die of pneumonia are in developing countries. Epidemiology Dadaab and Kakuma Refugee Camps (Kenya) o Data collected from 2007-2011 revealed that acute respiratory infections are the leading cause of morbidity and mortality in the camps. o In Dadaab camp acute respiratory infections were associated with 30% to 40% of deaths of children less than 5 years of age and up to 45% of morbidity in the same age group. Millennium Development Goal o In 2000, the United Nations Member States committed to Millennium Development Goal 4 to reduce the under five mortality rate by two thirds by 2015, compared to 1990. o Millennium Development Goal 4 can only be achieved by an intensified effort to reduce pneumonia deaths. Question: o Is reducing the incidence, morbidity, and mortality of pneumonia in children a high priority in the region where you practice? o What is being done in your area? Basic Pathophysiology o Most cases of pneumonia are caused by the aspiration of infective particles into the lower respiratory tract. o Organisms that colonize a childs upper airway can cause pneumonia. o Pneumonia can be caused by person to person transmission via airborne droplets. Etiology The common pathogens are a function of the patients age. The specific agent causing pneumonia can be determined in 1/3 to 2/3 of cases when cultures, antigen detection and serologic techniques are available. It is helpful to be aware of local outbreaks as clustering of cases is common. Pneumonia - Common Pathogens Age GroupCommon Pathogens (in Order of Frequency) NewbornGroup B Streptococci Gram-negative bacilli Listeria monocytogenes Herpes Simplex Cytomegalovirus Rubella 1-3 monthsChlamydia trachomatis Respiratory Syncytial virus Other respiratory viruses 3-12 monthsRespiratory Syncytial virus Other respiratory viruses Streptococcus pneumoniae Haemophilus influenzae Chlamydia trachomatis Mycoplasma pneumoniae From: Tintinalli JE et al. (2004). Emergency Medicine, A Comprehensive Study Guide, Sixth Edition. American College of Emergency Physicians. (pp. 784-789). McGraw-Hill. Toronto, ON. Pneumonia - Common Pathogens Age GroupCommon Pathogens (in Order of Frequency) 2-5 yearsRespiratory Viruses Streptococcus pneumoniae Haemophilus influenzae Mycoplasma pneumoniae Chlamydia pneumoniae 5-18 yearsMycoplasma pneumoniae Streptococcus pneumoniae Chlamydia pneumoniae Haemophilus influenzae Influenza viruses A and B Adenoviruses Other respiratory viruses From: Tintinalli JE et al. (2004). Emergency Medicine, A Comprehensive Study Guide, Sixth Edition. American College of Emergency Physicians. (pp. 784-789). McGraw-Hill. Toronto, ON. Pneumonia History Pneumonia History Fundamentals o Age o Presence of cough, difficulty breathing, shortness of breath, chest pain o Fever o Recent upper respiratory tract infections o Associated symptoms (e.g headache, lethargy, pharyngitis, nausea, vomiting, diarrhea, abdominal pain, rash) o Duration of symptoms Pneumonia History o Immunizations status o TB exposure o Maternal Chlamydia, Group B Strep status during pregnancy o Choking episodes o Previous episodes o Previous antibiotics Pneumonia History Ill contacts Travel history Day care attendance Animal exposure Dehydration is a sign of severe infection that may require hospitalization. Inquire about: Fluid and nutrition intake Urine output History Fundamentals Past Medical History Birth History Medications Allergies Immunization Status Home Environment Social History Family History Diagnosis Diagnosis Objectives o Recognition of the signs of pneumonia o Diagnosis in a community setting o Diagnosis in a health care setting o Differential Diagnosis RSV and TB o Diagnosis in the context of malnutrition, and considering HIV Recognition of Signs of Pneumonia o Tachypnea is the most sensitive and specific sign of pneumonia o Tachypnea had a Sensitivity of 61% and 79% and Specificity of 79% and 65% for pneumonia in malnourished and well- nourished Gambian children respectively WHO Definition of Tachypnea AgeRespiratory Rate (breaths/min) Indication of severe infection (breaths/min) 6070 2 to 12 months 50 12 months to 5 years 4050 Greater than 5 years 20 Other signs of pneumonia - Indrawing out-breathing-in Lower chest wall indrawing: with inspiration, the lower chest wall moves in From: Integrated Management of Childhood Illness. Chapter Three: Cough or difficulty breathing. World Health Organization. 2000 ”/chd/publications/referral_care/chap3/chap31.htm. Accessed February 2, 2012 Other signs of pneumonia - Nasal Flare Nasal flaring: with inspiration, the side of the nostrils flares outwards From: Integrated Management of Childhood Illness. Chapter Three: Cough or difficulty breathing. World Health Organization. 2000 ”/chd/publications/referral_care/chap3/chap31.htm. Accessed February 2, 2012 Diagnosis in Community Setting SIGNS Classify ASTreatment Tachypnea Lower chest wall indrawing Stridor in a calm child Severe PneumoniaRefer urgently to hospital for injectable antibiotics and oxygen if needed Give first dose of appropriate antibiotic TachypneaNon-Severe Pneumonia Prescribe appropriate antibiotic Advise caregiver of other supportive measure and when to return for a follow-up visit Normal respiratory rateOther respiratory illness Advise caregiver on other supportive measures and when to return if symptoms persist or worsen From: Pneumonia The Forgotten Killer of Children. Geneva: World Health Organization (WHO)/United Nations Childrens Fund (UNICEF), 2006. Infants at Risk of Pneumonia o Infants less than 3 months old with signs of pneumonia should be referred immediately to the nearest health facility because they are at high risk of severe illness and death. o Infants who were premature, and those with congenital heart disease or chronic lung disease are also at increased risk. Diagnosis in a Health Care Setting Vital signs that should routinely be taken in an Emergency Care setting include: Respiratory Rate Heart Rate Temperature Oxygen saturation (if available) Any child with an increased respiratory rate should be immediately identified as having possible pneumonia. Vital Signs o Both heart rate and respiratory rate are influenced by the presence of fever. o Heart rate increases by approximately 10 beats per minute for each 1 degree Celsius. o Respiratory Rate has been estimated to vary by 0.5-2 breath per minute to 5-11 breaths per minute for each 1 degree Celsius. Does this infant child have pneumonia? The Rational Clinical Exam, Journal of the American Medical Association Observation of the infant is the most important part of the examination does the child look sick? Respiratory rate should be calculated over two thirty second intervals, or one minute due to moment to moment variability. Auscultation is unreliable when examining infants. Does this infant child have pneumonia? Absence of tachypnea is the best individual finding for ruling out pneumonia. Chest indrawing, other signs of increased work of breathing and abnormal findings on auscultation can be used toward ruling in pneumonia. If clinical signs are negative (respiratory rate, auscultation, and work of breathing), it is unlikely that there will be chest x-ray findings. Pneumonia Severity Assessment MildSevere InfantsTemperature 38.5 C RR 70 breaths/min Moderate to severe recession Nasal Flaring Cyanosis Intermittent Apnea Grunting Respirations Not feeding Older ChildrenTemperature 38.5 C RR 50 breaths/min Severe difficulty in breathing Nasal Flaring Cyanosis Grunting Respirations Signs of dehydration From: Pneumonia The Forgotten Killer of Children. Geneva: World Health Organization (WHO)/United Nations Childrens Fund (UNICEF), 2006. Differential Diagnosis: A Focus on Respiratory Syncytial Virus (RSV) Respiratory Syncytial Virus (RSV) o RSV is the most common cause of LRTIs in children less than 1. o Infants and young children typically present with pneumonia or bronchiolitis. o Older children may have upper respiratory tract infection symptoms. o RSV is associated with apnea in infants. o Wheezing is common. RSV Seasonality o Seasonal outbreaks occur throughout the world. o In the northern hemisphere outbreaks peak in January and February. o In the southern hemisphere outbreaks peak in May, June and July. o In tropical climates outbreaks are often associated with the rainy season. Differential Diagnosis: Consider Tuberculosis Tuberculosis Common symptoms of tuberculosis include: o Chronic cough that has been present for more than 3 weeks and is not improving o Fever greater than 38C for at least two weeks, not attributable to other common causes o Weight loss or failure to thrive Tuberculosis Physical exam findings of children with pulmonary tuberculosis are similar to those of a lower respiratory tract infection. In children less than age five tuberculosis can progress rapidly from latent infection to active disease and serve as a sentinel case in the community. Consider the diagnosis of tuberculosis, especially in those children who fail to respond appropriately to routine treatment for pneumonia. Pneumonia in Malnourished Children Pneumonia in Malnourished Children History of cough, fast breathing and difficulty breathing were significant predictors of pneumonia in malnourished children. Only difficulty breathing was a significant predictor of pneumonia in well-nourished children. As malnourished children are a high risk group, those who present with a history of cough, fast breathing, or difficulty breathing should be treated with antibiotics. Fast breathing and lower chest wall indrawing are not specific predictors of pneumonia in malnourished children. Pneumonia and HIV infected Children Pneumonia and HIV infected Children The prevalence of HIV-1 in children admitted with severe pneumonia (by WHO criteria) in Africa is 55- 65%. The case fatality rate is 20-34%. This case fatality rate is 3-6 times higher for children infected with HIV compared to those not infected with HIV. Pneumonia caused by Pneumocystis jiroveci may be the first indicator of HIV infection, and lead to HIV testing and diagnosis. Question: How are children who may have pulmonary tuberculosis identified and treated? Malnourished children, and children with HIV are at high-risk for complications associated with pneumonia. How are these children managed where you practice? Management and Disposition Disposition o The decision whether the patient would be best managed at home or in a heath care setting is based on many factors, including the resources available. Admission Considerations o If caregivers are unable to care for the child, or to commit to following a treatment plan, the child should be admitted to a health care facility. o Any child less than three months of age. o Failure of outpatient treatment (worsening or no response to treatment after 24 to 72 hours). o Family lives in a remote area. Indications for Admission - IMCI o All Children with Very Severe Pneumonia need admission o Very Severe Pneumonia includes any of: nCough or difficult breathing plus at least one of the following: nCentral cyanosis nInability to breastfeed or drink, or vomiting everything nConvulsions, lethargy or unconsciousness nSevere respiratory distress (e.g. head nodding) nSome or all of the other signs of pneumonia (tachypnea, grunting, nasal flare, indrawing, changes in auscultation) Indications for Admission Age GroupIndications for Admission to Hospital InfantsOxygen Saturation 70 breaths /min Difficulty in breathing Intermittent apnea, grunting Not feeding Family not able to provide appropriate observation or supervision Older ChildrenOxygen Saturation 50 breaths /min Difficulty in breathing Grunting Signs of Dehydration Family not able to provide appropriate observation or supervision From: British Thoracic Society (BTS) of Standards of Care Committee. BTS Guidelines for the Management of Community Acquired Pneumonia in Childhood. Thorax. 2002;57: i1-i24. In-Patient Management o Consideration must be given to the provision of adequate hydration, oxygenation, nutrition, antipyretics and pain control. o Monitoring should include: nRespiratory rate nWork of breathing nTemperature nHeart rate nOxygen saturation (if available) nFindings on auscultation. In-Patient Considerations o Due to the risk of transmission, a child suspected of having pneumonia should be cared for in an area that is isolated from others to who are at risk of becoming infected. o Contact precautions by health care workers such as hand washing, gloves, gowns and masks to prevent transmission between patients are often appropriate. Criteria for Intensive Care If intensive care is available consider the following: The patient is failing to maintain an oxygen saturation of 92% in FiO2 of 0.6. The patient is in shock. There is a rising respiratory rate and rising pulse rate with clinical evidence of severe respiratory distress and exhaustion, with or without a raised arterial carbon dioxide tension (PaCO2). There is recurrent apnea or slow irregular breathing. Management of Respiratory Distress and Respiratory Failure: ABCs and Intubation Airway o Support the airway (position of comfort for the child) or open the airway (chin lift or jaw thrust). o Clear the airway (suction nose and mouth, remove any foreign body). o Insert an oropharyngeal or nasopharyngeal airway as indicated. Breathing o Assist ventilation (e.g., bag-mask ventilation) as needed o Provide oxygen o Continuously monitor oxygen saturation o Consider use of CPAP or BIPAP o Prepare for endotracheal intubation as needed o Administer medications as needed Circulation o Monitor heart rate and rhythm o Establish vascular access as indicated (for fluid therapy and medications) Indications for Intubation o Inadequate oxygenation or ventilation o Inability to maintain and/or protect the airway o Potential for clinical deterioration o Prolonged patient transport or diagnostic studies Indications for Intubation Respiratory failure is the most common indication for intubation in children with pneumonia Clinical evidence of respiratory failure: Poor or absent respiratory effort Poor colour Obtunded mental status Oxygen saturation and end-tidal carbon dioxide can be used to support the decision to intubate, but intubation should not be delayed if there is clinical evidence of respiratory failure Relative Contraindications to Intubation o No absolute contraindications o Caution using rapid sequence intubation with neuromuscular blockade in a child difficult to bag and mask o High-risk intubation (e.g suspected epiglottitis) o Airway trauma that may require a surgical airway Intubation Pointers Detailed Pediatric Airway management is beyond the scope of this module Endotracheal tube size calculations: Uncuffed tube = 4 + (age in years/4) Cuffed tube = 3.5 + (age in years/4) Ventilation: begin with 8-10 breaths per minute Question: o What resources do you have available to care for children with pneumonia? o What are the criteria for hospital admission/ transfer to another facility/intensive care where you practice? Further Testing Chest X-ray o Confirmation of pneumonia by chest x-ray is not indicated in children with mild, uncomplicated lower respiratory tract infections who will be treated at outpatients. Chest X-ray A study in South Africa randomized children age 2-59 months who met the WHO case definition of pneumonia to have a chest x-ray, or not. There was no clinically identifiable subgroup of children within the WHO case definition who were found to benefit from a chest x-ray. It was concluded that there was no benefit in routine chest x-ray of ambulatory children with lower respiratory-tract infection over two months of age. Chest X-ray Consider if available and: o Infection is severe o Diagnosis is otherwise inconclusive o To exclude other causes of shortness of breath (e.g foreign body, heart failure) o To look for complications of pneumonia un