Usefulness of Pediatric Respiratory Assessment Measure Score in Assessing the Severity and Outcome of Acute Exacerbation of Wheeze in Children

Dr. Venugopal Reddy. I *¹, Dr. G. Siva Kartheek Reddy ², Dr Dinesh Kumar Vuppu ³, Dr Murali Mohan Voona ⁴

 

1. Medical Director and Consultant Pediatrician, Ovum Hospital, Bangalore.

2. Consultant Pediatrician, Best Care Hospital, Andhra Pradesh.

3. Consultant Neonatologist and Pediatrician, Ovum Hospital, Bangalore.

4. Consultant Pediatrician and Neonatologist, Ovum Hospital, Bangalore.

Corresponding Author: Dr. Venugopal Reddy. I, Medical Director and Consultant Pediatrician, Ovum Hospital, Bangalore.

Copy Right: © 2023, Dr. Venugopal Reddy. I, This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Received Date: May 30, 2023

Published Date: June 15, 2023

DOI: 10.1027/marpe.2023.0184

Introduction

Asthma is one of the most common chronic diseases in the world. It is a major cause of morbidity and mortality throughout the world and there is evidence that its prevalence has increased considerably over the past 20 years, especially in children[1].

Asthma is a worldwide problem, with an estimated 300 million affected individuals'. The global prevalence of asthma ranges from 1% to 18% of the population in different countries. There is good evidence that international differences in asthma symptom prevalence have reduced, particularly in the 13-14 year age group, with decreases in prevalence in regions where prevalence was previously low[2]. The increase in the prevalence of asthma has been associated with an increase in atopic sensititisation, and is paralleled by similar increase in other allergic disorders such as eczema and rhinitis. In India, the reported prevalence of childhood asthma varies from less than 5% to as high as 20% [3].

Asthma is a chronic inflammatory diseases of the lung airways resulting in episodic airflow obstruction. The chronic inflammation is associated with airway hyper responsiveness that leads to recurrent episodes of wheezing, breathlessness, chest tightness, and coughing, particularly at night or in the early morning. These episodes are usually associated with widespread, but variable, airflow obstruction. Airflow obstruction during exacerbations can become extensive resulting in life threatening respiratory insufficiency [2].

Guidelines for the management of acute pediatric asthma hinge on the objective assessment of asthma severity, generally measured by lung function tests such as peak expiratory flow rate or spirometry[2]. Unfortunately, these lung function test are nearly impossible to obtain preschool aged children because of poor coordination and in 35% to 50% of school aged children, because of severity of illness or poor familiar it with the technique[5]. With preschool aged children representing over half the patients treated for acute asthma[6], it is estimated that three quarters of asthmatic children cannot perform standard lung function test in th emergency setting[7].

Clinical scores can serve as simple and inexpensive tools to assess asthma severity for the entire paediatric age groups. More than 16 different clinical scores have been reported for assessing asthma severity8. In spite of the availability of many asthma scores, information on the clinimetric properties of score in terms of reliability, validity and responsiveness are scarce. Hence emphasis is on evaluating the properties of already existing scores.

The Paediatric Respiratory Assessment Measure (PRAM) score has been found to be an attractive score for assessing asthma severity and response to treatment[9]. The PRAM is a 12 point clinical score rubric that captures a patient’s condition in scalene muscle contraction, suprasternal retractions, wheezing, air entry, and oxygen saturation. Birken et al in a study of asthma severity scores in preschool aged children identified PRAM score as one of the scores with good measurement properties [10]. Ducharme et al developed and validated the PRAM score against respiratory resistance and proved this as discriminative and responsive to change". This study aims to determine the performance characteristics of PRAM score in children with acute exacerbation of asthma.

Review of literature

History of Asthma

The term Asthma comes from the Greek verb aazein, meaning “to pant, to exhale with the mouth open, sharp breath”. In the Iliad, a Greek epic poem, the expression asthma appeared for the first time.

The Corpus Hippocraticum, by Hippocrates (460-360 BC), is the earliest text where the word asthma is found as a medical term. Hippocrates said spasm linked to asthma were more likely to occur among anglers, tailors and metalworkers. Hippocrates recommended vapour inhalation.

Aretaeus of CappadociaftlOO AD), an ancient Greek master clinician, wrote a clinical description of asthma. Galen (130-200 AD), an ancient Greek physician, wrote several mentions of asthma which generally agreed with the Hippocrates text and to some extent those of Aretaeus.

Moses Maimonides (1135-1204 AD), the rabbi and philosopher who lived in Andalucia (Spain), Morocco and Egypt wrote Treatise of Asthma for Prince Al-Afdal, a patient of his. He noted that his patients symptoms often started as a common cold during the wet months. Eventually the patient gasped for air and couged until phlegm was expelled. He noted that the dry months of Egypt helped asthma sufferers.

During the early 1800’s asthma was rarely mentioned in medical literature. In the 19^th century, inhalation therapy was introduced to the western world with the use °f Datura stramonium, a congener of atropine. This was available as asthma cigarettes.

There has been an increase in the prevalence of childhood asthma from all over the world and similar trends have been observed in India. Paramesh et al in a hospital based study on the prevalence of Asthma in Bangalore found a 3 fold increase in the prevalence in the last 20 years [13]. The increased prevalence correlated well with demographic changes of the city. He also identified an increase in incidence of persistent asthma from 20% to 27.5% and persistent severe asthma 4% to 6.5% between 1994-99. The ISAAC study found a wide variation in the prevalence of asthma from different parts of the world and even from different parts of same country[14]. This regional variation is due to differing levels of pollution, infections, industrialization, socio-economic, educational status, climate and population densities. This study found the prevalence in 6-7 years, 13-14 years in India to be around 6% which is at the lower end of the world wide prevalence range. Within the country, Chennai was one of the high prevalence centres with a prevalence for more than 6% [15].

The economic burned of asthma is considerable both in terms of direct medical costs (such as hospital admissions and cost of pharmaceuticals) and indirect medical costs (such as time lost from work and premature death). Although from the perspective of both the patient and society the cost to control asthma seems high, the cost of not treating asthma correctly is even higher. There is every reason to believe that the substantial global burden of asthma can be dramatically reduced through efforts by individuals, their health care providers, health care organizations, and local and national governments1.

Definition

According to the Global Initiative for Asthma (GINA) 2008 guidelines, asthma is defined as [2]:

Asthma is a chronic inflammatory disorder of the airways in which many cells and cellular elements play a role. The chronic inflammation is associated with airway hyper responsiveness that leads to recurrent episodes of wheezing, breathlessness, chest tightness and coughing, particularly at night or in the early morning. These episodes are usually associated with widespread, but variable, airflow obstruction within the lung that is often reversible either spontaneously or with treatment.

Factors Influencing the Development and Expression of Asthma

Factors that influence the risk of asthma can be divided into those that cause the development of asthma and those that trigger asthma symptoms; or both. The former category includes host factors (which are primarily genetic) and the latter category usually consists of environmental factors.

Genetic

Asthma has a heritable components, but it is not simple. Current data show that multiple genes may be involved in the pathogenesis of asthma and different genes may be involved in different ethnic group17 l8. The search for genes linked to the development of asthma has focused on four major areas:

1. Production of allergen specific IgE antibodies (atopy)
2. Expression of airway hyperresponsiveness
3. Generation of inflammatory mediators, such as cytokines, chemokines, and growth factors.
4. Determination of theTatio between Thl and Th2 immune responses (as relevant to the hygiene hypothesis of asthma).

According to the EGEA study (Epidemiological study on the genetics and environment of asthma, atopy and bronchial hyperresponsiveness) analysis showed linkage of asthma severity scores to the locus on chromosome 18p II, 2p33. 1019.

Obesity

Obesity has also been shown to be a risk factor for asthma. Certain mediators such as leptons may affect airway function and increase the likelihood of asthma development20,21.
 

Gender

Male gender is a risk factor for asthma in children. Prior to the age of 14, the prevalence of asthma is nearly twice as great in boys as in girls. As children grow older the difference between the sexes narrows, and by adulthood the prevalence of asthma is greater in women than in men[22]. The reason for this gender related difference is not clear.

Environmental Factors

Allergens

Although indoor and outdoor allergens are well-known to cause asthma exacerbations, their specific role in the development of asthma is stillnot fully resolved. Birth cohort studies have shown that sensitization to house dust mite, allergens, cat dander, dog dander and Aspergillus mold are independent risk factors for asthma like symptoms in children upto 3 years of age [23, 24]. However, the relationship between allergen exposure and sensitization in children is not straightforward. It depends on the allergen, the dose, the time of exposure, the child’s age and probably genetics as well.

Infections

During infancy, a number of viruses have been associated with the inception of the asthmatic phenotypes. Recurrent wheezing episodes in early childhood are associated with common respiratory viruses like respiratory syncytial virus, rhino virus, influenza, parainfluenza, human metapnuemo virus. Injuries viral infections of the airways manifesting as pneumonia or bronchiolitis requiring hospitalization are risk factors for persistent asthma in childhood.

The “hygiene hypothesis” of asthma suggests that exposure to infections early in life influences the development of a child immune system along a “non allergic” pathway, leading to a reduced risk of asthma and other allergic diseases. Early exposure to respiratory infections may favour a Thl type of response and thus switch off Th2 response giving protection against asthma and other allergic diseases[25].

The interaction between atopy and viral infections appear to be a complex relationship, in which the atopic state can influence the lower airway response to viral infections, viral infections can then influence the development of allergic sensitization and interactions can occur when individuals are exposed simultaneously to both allergens and viruses[26].

Tobacco smoke

Exposure to tobacco smoke, both prenatally and after birth, is associated with measurable harmful effects including a greater risk of developing asthma like symptoms in early childhood.

Outdoor / indoor air pollution

Outbreaks of asthma exacerbations have been shown to occur in relationship to increased levels of air pollution, and this may be related to a general increase in the level of pollutants or to specific allergens to which individuals are sensitized. Similar associations have been observed in relation to indoor pollutants, eg., smoke and fumes from gas and biomass fuels used for heating and cooling, molds, and cockroach infestations.

Diet

Infants fed formulas of intact cow’s milk or soy protein have a higher incidence of wheezing illnesses in early childhood compared with those fed breast milk[27].

Path physiology of asthma

• Airway inflammation is associated with airway hyper reactivity or bronchial hyper responsiveness, which is defined as the inherent tendency of the airways to narrow in response to various stimuli (e.g., environmental allergens and irritants).
• Airway inflammation leads to cellular inflammatory infiltrate and exudates distinguished by eosinophils, but also including other inflammatory cell types (neutrophils, monocytes, lymphocytes, mast cells, basophils). These cells fill and obstruct the airways and induce epithelial damage and desquamation into the airway lumen.
• Helper T lymphocytes and other immune cells produce proallergenic, pro inflammatory cytokines (IL-4, IL-5, IL-6, IL-13) and chemokines that mediate the inflammatory process.
• Pathogenic immune responses and inflammation results from a breach in the normal immune regulatory process (Th2 lymphocytes). All these lead to aberrant repair and structural changes in airway[28].

Airway inflammation in asthma may represent a loss of normal balance between two ‘‘opposing” populations of Thl lymphocytes. Thl cells produce interleukin (IL-2) and IFN-a, which are critical in cellular defiance mechanism in response to infection. Th2 in contrast, generates a family of cytokines (IL-4, IL-5, IL- 6, IL-9 and IL-13) that can mediate allergic inflammation. The current “hygiene hypothesis” of asthma illustrates how this cytokine imbalance may explain some of the dramatic increases in asthma prevalence.

Clinical features

Consider asthma if any of the following signs or symptoms is present:

• Frequent episodes of wheezing - more than once a month
• Activity induced cough or wheeze
• Cough particularly at night during periods without viral infections
• Absence of seasonal variation in wheeze
• Symptoms that persists after age of 3 years
• Symptoms occur or worsen in the presence of aerollergens (house dust mites, companion animals, fungi, and cockroach), pollen, respiratory (viral) infections, strong emotional expression and tobacco smoke.
• The child’s colds repeated “go to the chest” or take more than 10 days to clear up.
• Symptoms improve when asthma medication is given.

Making a definite diagnosis of asthma in children 5 years and younger is challenging because episodes of respiratory symptoms such as wheezing and cough are also common in children who do not have asthma, particularly in those younger than 3 years.

The young the child, the greater is the likelihood that an alternative diagnosis may explain the recurrent wheeze. Lung function measurement that are key to the diagnosis of asthma in older children and adults are not reliable in children less than 5 years.

Some children do not have typical symptoms of wheeze. The variants seen are:

Cough variant asthma

Patients with cough variant asthma have chronic cough as their principal, if not only symptoms. It is particularly common in children and is often more problematic at night. Evaluation of these children during day can be normal.

 

Exercise induced bronchoconstriction

Physical activity is an important cause of asthma symptoms for most asthma ; patients and for some it is the only cause. Exercise induced bronchoconstruction I, typically develops within 5-10 minutes after completing exercise. Patients experience typical asthma symptoms or sometimes a troublesome cough. Rapid improvement of post exceptional symptoms after inhaled 02 agonist use, or their prevention by pre-treatment with an inhaled 02 agonist before exercise, supports a diagnosis of asthma.

Some children with asthma present only with exercise induced symptoms.

Physical examination

Signs suggestive of generalized airflow obstruction include generalized rhonchi, prolonged expiration and chest hyperinflation.

Levels of Asthma Control

Asthma control may be defined in a variety of ways. In general, the term control may indicate disease prevention, or even cure. However, in asthma, where neither of these are realistic options at present, it refers to control of the manifestations of disease. It is recommended that treatment be aimed at controlling the clinical features of disease, including lung function abnormalities.

Acute exacerbation of asthma

Exacerbations of asthma are episodes of progressive increase in shortness of breath, cough, wheezing, chest tightness or a combination of symptoms.

Severe exacerbations are potentially life threatening and their treatment requires close supervision. Most patients with severe asthma exacerbation should be treated in an acute care facility. Patients at high risk of asthma related death also require close attention.

Milder exacerbations, defined by a reduction in peak flow of less than 20% nocturnal awakening, and increased use of short acting b2 agonists can usually be treated in a community setting. If the patient responds to the increase in inhaled bronchodilator treatment after the"first few doses, referral to an acute care facility is not required but further management under the direction of a primary care physician may include the use of systemic glucocorticosteroids. Patient education and review of maintenance therapy should also be undertaken.

Patient a high risk of asthma related death require close attention and should be encouraged to seek urgent care early in the course of their exacerbations. These patients include those:

• With a history of near fatal asthma requiring intubation and mechanical ventilation.
• Who have had a hospitalization or emergency care visit for asthma in the past year.
• Who are currently using or have recently stopped using oral glucocorticosteroids.
• Who are not currently using inhaled glucocorticosteroids.
• Who are over dependent on raid acting inhaled p2 agonists, especially those who use more than one canister of salbutamol (or equivalent) monthly.
• With a history of psychiatric disease or psychosocial problems, including the use of sedatives.
• With a history of non compliance with an asthma medication plan.

Assessment of severity

A brief history and physical examination pertinent to the exacerbation should be conducted concurrently with the prompt initiation of therapy.

The history should include; severity and duration of symptoms, including exercise limitation and sleep disturbance; all current medications, including dose (and device) prescribed, dose usually taken, dose taken in response to the deterioration, and the patients response (or lack thereof) to this therapy; time of onset and cause of the present exacerbation; and risk factors for asthma related death.

The physical examination should assess exacerbation severity by evaluating the patient ability to complete a sentence, pulse rate, respiratory rate, use of accessory muscles, and other signs. In a study by Singhi S et al to identify clinical signs and symptoms that predict hypoxemia in asthma, they found that physical examiantion should include at least accessory muscle use and pulses paradoxus since these predict hypoxemia the best.

Any complicating factors should be identified (eg. Pneumonia, atelectasia, pneumothorax, or pneumomediastinum).

Laboratory Investigations in Acute Asthma

• X-ray chest: Routine X-ray chest is not recommended unless a pneumothorax or physical signs suggestive of parenchymal disease are present.
• ABG: This is useful in severe exacerbations to assess the severity of respiratory acidosis. Usual findings in the early phase are hypoxemia and hypocarbia. In later stage once respiratory ailure ensures PaCO2 will build up and profound decrease in pH occurs. However the decision to intubate should not be made on ABG parameters alone. Assessment of respiratory effort, SpO2 and level of consciousness should guide the decision.

• Pulmonary function test: Spirometry and PEFR are objected measures of assessing the degree of ajrway obstruction. However this is difficult to perform in children <5 years.

Severity of asthma exacerbations

The severity of the exacerbation determines the treatment administered.

Indices of severity, particularly PEF (in patients older than 5 years), pulse rate, respiratory rate, and pulse oximetry, should be monitored during treatment.

Asthma severity scoring systems

Clinical scores can serve as simple and inexpensive tools to assess asthma severity for the entire paediatric age groups. More than 16 clinical scores have been reported for assessing asthma severity8. A good scoring system should be reproducible, obtainable in children of all ages, reflect the severity of underlying pathophysiology and be useful in clinical decision making.

Wood downes - leeks asthma score

In 1972, Wood et al devised a clinical scoring system to detect impending or existing respiratory failure in childhood status asthmatics. It was based on evaluation of oxygenation, gas exchange work of breathing, airway obstruction and cerebral function. A significant correlation was noted between the scores and levels of PaO2 and PCO2.[29]

 

1. Baker et al[30] evaluated the correlation of the Wood-Downes-Lecks clinical asthma score with outcome in 210 consecutive known asthmatic children presenting to an urban emergency department for treatment of acute asthma. They found that Wood’s score alone is not a reliable indicator of severity of acute asthma s judged by subsequent disability (prolonged hospitalization, ongoing disability following ER discharge).

Merits: Useful in ICU set up to identify respiratory failure

Demerits:

1. Cannot be used in primary care level as it includes estimation of PaO2.
2. When used on mild to moderately severe acute asthmatic children, and without the cyanosis component, it correlated poorly with arterial oxygen tension.Hence found to be useful only in very sick children.

1. Baker et al[30] evaluated the correlation of the Wood-Downes-Lecks clinical asthma score with outcome in 210 consecutive known asthmatic children presenting to an urban emergency department for treatment of acute asthma. They found that Wood’s score alone is not a reliable indicator of severity of acute asthma s judged by subsequent disability (prolonged hospitalization, ongoing disability following ER discharge).

Asthma severity score (SS)

This scoring system consists of 3 variables - wheeze, heart rate, accessory muscle use, each on 0-3 scale.

Merits

1. Simple objective method which can be used in primary care level

Young et al found ASS to have very good inter observer agreement with a moderate relationship to oxygenation and FEVI. FEV1 correlated with accessory muscle use scores and heart rate correlated with saturation. Bishop et al32 found that an ASS score of moderate or worse (greater than 3) had sensitivity of 97% and specificity of 50% for predication of admission.

Clinical asthma score (CAS)

CAS was developed as a modification of Wood-Downe score. CAS consisted °f five clinical characteristics: respiratory rate, wheezing, in drawing, observed dyspnea, and inspiratory to expiratory ratio which is scored 0, 1 or 2. The score for each variable are added together with a possible total score of 10.

Merits

Parkin Pc et al33 found that CAS was valid, with a strong correlation with length of hospital stay, drug dosing interval, responsive with a significant change in CAS from admission to discharge.

Demerits

• Inspiratory: Expiratory ratio, one of the components of the score is difficult to measure in young children.
• Degree of dyspnea is a subjective assessment. Accurate estimation of degree of dyspnea is difficult in young children.

Pulmonary index (PI)

Becker AB et al34 devised pulmonary index for asthma in 1984. It had 4 components. The PI was derived from respiratory rate, wheezing, inspiratory expiratory ratio, and use of accessory muscles. Becker et al found the PI before treatment correlated significantly with the mean percent of forced expiratory volume •n the first second to force vital capacity ratio (FEV1/FVC). The PI 30 minutes after treatment correlated significantly with all tests of pulmonary function performed.

 

Demerits:

Inspiratory: Expiratory ratio, one of the components of the score is difficulty to measure in young children.

Pulmonary score (PS)

Becker et al34 devised pulmonary index for asthma in 1984. It had 4 components. The pulmonary score is derived from the pulmonary index. The I:E component was removed and the respiratory rate was enhanced by the separating this component into 2 categories by age. Thus PS is the aggregate of 3 items, each scored on a 0-3 scale.

Merits

• Simple objective measure
• Can be used in primary care level
• Recommended by IAP respiratory chapter
• Smith SR et al studied the correlation of PS with PEFR in children aged 5-12 yrs and concluded that PS is a practical substitute to estimate airway obstruction in children who are too young or too sick to obtain PEFRs.

 

 

Demerits

Does no measure oxygen saturation, which is an important objective Measurement which can predict hospitalization.

Modified pulmonary index score (MPIS)

In the modified pulmonary index score) MPIS), 6 categories are evaluated: oxygen saturation, accessory muscle use, inspiratory to expiratory flow ratio, degree of wheezing, heart rate, and respiratory rate. For each of these 6 measurements or observations, a score of 90 to 3 is assigned. Carol CL et al36 identified MPIS as a highly reproducible and valid indicator of severity of illness in children with asthma. Merits

It includes SpO2 by pulse oximetry, which is an important objective measurement which can predict hospitalzition.

Demerits

Inspiratory: expiratory^ratio is difficult to measure in young children. Paediatric asthma severity score (PASS)

It has six parameters: amount of wheeze, work of breathing as assessed by use of accessory muscles, air entry, tachypnea, presence of prolonged expiration and mental status. For each of these parameters a score of 0 to 2 was assigned.

 

Merits

1. It is a simple tool that was developed for use in asthma severity studies. It is a modified version of the pulmonary index, a previously validated clinical asthma severity score. The PASS is less comprehensive but easier to use than the pulmonary index.
2. Gorelick MH et al37 identified that PASS is a reliable and valid measure of asthma severity in children and showed both discriminative and responsive prosperities. They found that the PASS scores correlated with the PEFR and SpO2 measurement in children >6 6 years. S Chu et al38 found that PASS can be used as a predictor of length of stay in the ED for children presenting with an acute exacerbation of asthma.

Merits

Oxygen saturation is an objective measurement which can predict need for hospitalization.

Demerits

1. Degree of dyspnea is difficulty to assess in young children
2. Intercostals in drawing, one of the parameters of this score when present suggests decreased compliance of lung and hence suggests parenchymal lung diseases. Intercostals in drawings are less specific for assessing the severity of asthma[29].

Paediatric respiratory assessment measure (PRAM) score

This score consists of 5 variables - suprasternal retractions, scalene retractions, air entry, wheeze, oxygen saturation. It is a 12 point scoring system with the variables scored from 0 to 2 or 3.

The PRAM score was initially described as preschool respiratory assessment measure by Ducharme FM et al11. They elaborated and validated a Preschool Respiratory Assessment Measure that would accurately reflect the severity of airway obstruction and the response to treatment in young patients with asthma. They validated the PRAM scores against concurrent measurement of lung function in children aged 3-6 years. Subsequent studies by Ducharme FM et al9 showed good performance characteristics of PRAM in all age groups.

Birken CS et al[10] in an analysis of asthma severity scores in preschoolers concluded that PRAM was one of the scores to demonstrate adequate correlation coefficients between asthma severity scores and clinical measures (length of stay, drug dosing interval, 02 saturation, health professional assessment, PaO2, PaCO2).

They concluded that score such as CAS, PRAM have more rigorously evaluated their measurement properties. Robidas 1 et al[40] in a study comparing PRAM and PASS scores found both scores to be valid measures of asthma severity in children and show both discriminative and responsive properties with PRAM showing greater responsiveness.

Geelhoed GC et al[43] in another study evaluating the initial SPO2 and outcome of children with asthma concluded that the initial level of SPO2 reflects severity as it predicts the likelihood of poor outcome. This predictive quality of SPO2 is independent of current or past clinical factors. Keogh KA et al[44,46] in study to identify predictors of hospitalization in children factors. Keogh KA et al in a study to identify predicators of hospitalization in children with severe asthma identified several major risk factors - previous ICU admission baseline SPO2 <92%, CAS score of >6 need for hourly salbutamol nebulisation about 4 hrs after steroid therapy. Oxygen saturation has been studied by Mehta SV et al45 as predictor of prolonged, frequent bronchodilator therapy in children with acute asthma. SPO2 <91% was found to predict the need for frequent bronchodilator therapy >4 hrs.

Treatment

The following treatments are usually administered concurrently to achieve the most rapid resolution of the exacerbation:

Oxygen

To achieve oxygen saturation of >95% in children oxygen should be administered by nasal cannulae, by mask or rarely by head box in some infants. Oxygen therapy should be titrated against pulse oximetry to maintain satisfactory OxYgen saturation.

Rapid acting inhaled £2 agonists

Rapid acting inhaled 02 agonists should be administered at regular intervals. A reasonable approach to inhaled therapy in exacerbations, therefore, would be the initial use of continuous therapy, followed by intermittent on demand therapy for hospitalized patients. There is no evidence to support the routine use of intravenous 02 agonists in patients with severe asthma exacerbations.

Ipratropium bromide

A combination of nebulized 02 agonist with an anticholinergic (ipratropium bromide) may produce better bronchodilation than either drug alone. Combination 02 agonist / anticholinergic therapy is associated with lower hospitalization rate and greater improvement in PEF and FEV1.

Systemic glucocorticosteroids

Systemic glucocorticosteroids speed resolution of exacerbations and should be utilized in the all but the mildest exacerbations especially if:

02 - agonist: Consider aminophlline in an high dependency unit (HDU) or PICU with severe of life threatening bronchospasm unresponsive to maximal doses of other bronchodilators and systemic steroids with close and careful monitoring. Aminophylline is used in a loading dose of 5mg/kg as an infusion over 30 minutes followed by. lmg/kg/hr as continuous infusion. The loading dose is omitted if chid is already on theophylline.

Intravenous terbutaline infusion in acute severe asthma:

Terbutaline is recommended as a useful adjunct in asthma in those patients who fail to respond to standard initial therapy. Terbutaline was found to be effective and safe at doses of 1-5 ug/KG/min. side effects of the drug reported were increase in heart rate, significant fall in diastolic blood pressure which may also require inotropes and hypokalemia.

Heliox:

Heliox, a blend of helium and oxygen, reduces airway resistance and may be a therapeutic option for severe refractory asthma in intubated patients as there is a decrease in peak inspiratory pressure and paCO2.0 the mixture may improve the distribution of inhaled agents and lead to a faster rate of resolution of obstruction. But there is insufficient evidence to establish the utility of heliox in routine emergency room treatment.

 

Sedatives:

Sedation should be strictly avoided during exacerbations of asthma because of the respiratory depressant effect of anxiolytic and hypnotic drugs.

Ventilation in asthma:

Ventilator assistance can be lifesaving. Both non-invasive and invasive techniques are available. The generally accepted indication are progressive CO2 retention, obtundation and impending cardiopulmonary collapse. The goal of ventilator support is maintain adequate gas exchange until bronchodilators and corticosteroids relive the airflow obstruction vantilatory strategies that provide the longest possible expiratory time are desired sa that dynamic lung inflation is minimized. This goal is accomplished by combining the smallest tidal valume with the slowest ventilatory rate and fastest inspiratory time to keep a static end inspiratory pressure (plateau pressure) of less than 30cm H20.

Aims and Objectives

Aim of study

To study the usefulness of PRAM score in assessing the severity and outcome of an acute exacerbation of wheeze in children aged 1 - 12yrs.

To identify the PRAM score predicting the need for hospitalization and ICU care.