The BTS guidelines for acute asthma in children recommend administering oral steroids early in the treatment of asthma attacks. It is advised to give a dose of 20 mg prednisolone for children aged 2–5 years and a dose of 30–40 mg for children over 5 years old. If a child is already taking maintenance steroid tablets, they should receive 2 mg/kg prednisolone, up to a maximum dose of 60 mg. If a child vomits after taking the medication, the dose of prednisolone should be repeated. In cases where a child is unable to keep down orally ingested medication, intravenous steroids should be considered. Typically, treatment for up to three days is sufficient, but the duration of the course should be adjusted based on the time needed for recovery. Tapering off the medication is not necessary unless the steroid course exceeds 14 days. For more information, refer to the BTS/SIGN Guideline on the Management of Asthma.

The typical range for the partial pressure of carbon dioxide (pCO2) is 4.4-6.4 kilopascals (kPa). In terms of arterial blood gas (ABG) results, the normal range for pO2 (partial pressure of oxygen) is 10-14.4 kPa or 70-100 millimeters of mercury (mmHg). The normal range for pCO2 is 4.4-6.4 kPa or 35-45 mmHg. Additionally, the normal range for bicarbonate levels is 23-28 millimoles per liter (mmol/L).

Further Reading:

Arterial blood gases (ABG) are an important diagnostic tool used to assess a patient’s acid-base status and respiratory function. When obtaining an ABG sample, it is crucial to prioritize safety measures to minimize the risk of infection and harm to the patient. This includes performing hand hygiene before and after the procedure, wearing gloves and protective equipment, disinfecting the puncture site with alcohol, using safety needles when available, and properly disposing of equipment in sharps bins and contaminated waste bins.

To reduce the risk of harm to the patient, it is important to test for collateral circulation using the modified Allen test for radial artery puncture. Additionally, it is essential to inquire about any occlusive vascular conditions or anticoagulation therapy that may affect the procedure. The puncture site should be checked for signs of infection, injury, or previous surgery. After the test, pressure should be applied to the puncture site or the patient should be advised to apply pressure for at least 5 minutes to prevent bleeding.

Interpreting ABG results requires a systematic approach. The core set of results obtained from a blood gas analyser includes the partial pressures of oxygen and carbon dioxide, pH, bicarbonate concentration, and base excess. These values are used to assess the patient’s acid-base status.

The pH value indicates whether the patient is in acidosis, alkalosis, or within the normal range. A pH less than 7.35 indicates acidosis, while a pH greater than 7.45 indicates alkalosis.

The respiratory system is assessed by looking at the partial pressure of carbon dioxide (pCO2). An elevated pCO2 contributes to acidosis, while a low pCO2 contributes to alkalosis.

The metabolic aspect is assessed by looking at the bicarbonate (HCO3-) level and the base excess. A high bicarbonate concentration and base excess indicate alkalosis, while a low bicarbonate concentration and base excess indicate acidosis.

Analyzing the pCO2 and base excess values can help determine the primary disturbance and whether compensation is occurring. For example, a respiratory acidosis (elevated pCO2) may be accompanied by metabolic alkalosis (elevated base excess) as a compensatory response.

The anion gap is another important parameter that can help determine the cause of acidosis. It is calculated by subtracting the sum of chloride and bicarbonate from the sum of sodium and potassium.

According to the brit-thoracic guidelines, if a patient with COPD continues to experience respiratory acidosis even after receiving standard medical therapy for one hour, it is recommended to consider using non-invasive ventilation (NIV). This is especially important if the patient’s hypoxia and hypercapnia are worsening despite the initial treatment.

Further Reading:

Arterial blood gases (ABG) are an important diagnostic tool used to assess a patient’s acid-base status and respiratory function. When obtaining an ABG sample, it is crucial to prioritize safety measures to minimize the risk of infection and harm to the patient. This includes performing hand hygiene before and after the procedure, wearing gloves and protective equipment, disinfecting the puncture site with alcohol, using safety needles when available, and properly disposing of equipment in sharps bins and contaminated waste bins.

To reduce the risk of harm to the patient, it is important to test for collateral circulation using the modified Allen test for radial artery puncture. Additionally, it is essential to inquire about any occlusive vascular conditions or anticoagulation therapy that may affect the procedure. The puncture site should be checked for signs of infection, injury, or previous surgery. After the test, pressure should be applied to the puncture site or the patient should be advised to apply pressure for at least 5 minutes to prevent bleeding.

Interpreting ABG results requires a systematic approach. The core set of results obtained from a blood gas analyser includes the partial pressures of oxygen and carbon dioxide, pH, bicarbonate concentration, and base excess. These values are used to assess the patient’s acid-base status.

The pH value indicates whether the patient is in acidosis, alkalosis, or within the normal range. A pH less than 7.35 indicates acidosis, while a pH greater than 7.45 indicates alkalosis.

The respiratory system is assessed by looking at the partial pressure of carbon dioxide (pCO2). An elevated pCO2 contributes to acidosis, while a low pCO2 contributes to alkalosis.

The metabolic aspect is assessed by looking at the bicarbonate (HCO3-) level and the base excess. A high bicarbonate concentration and base excess indicate alkalosis, while a low bicarbonate concentration and base excess indicate acidosis.

Analyzing the pCO2 and base excess values can help determine the primary disturbance and whether compensation is occurring. For example, a respiratory acidosis (elevated pCO2) may be accompanied by metabolic alkalosis (elevated base excess) as a compensatory response.

The anion gap is another important parameter that can help determine the cause of acidosis. It is calculated by subtracting the sum of chloride and bicarbonate from the sum of sodium and potassium.

Intercostal artery laceration during the insertion of a chest drain is a potentially life-threatening complication. Although rare, it occurs more frequently than other complications mentioned. To minimize the risk of damage to underlying structures and unsightly scarring, the British Thoracic Society (BTS) recommends inserting chest drains within the safe triangle. This triangle is defined by the base of the axilla, the lateral border of the latissimus dorsi, the lateral border of the pectoralis major, and the 5th intercostal space.

Possible complications associated with the insertion of small-bore chest drains include puncture of the intercostal artery, organ perforation due to over-introduction of the dilator into the chest cavity, hospital-acquired pleural infection from non-aseptic techniques, inadequate stay suture leading to the chest tube falling out, and tube blockage, which may be more common with smaller bore Argyle drains.

When using an intercostal approach, it is important to place the chest drain closer to the superior border of the rib below in the intercostal space. This positioning helps avoid injury to the intercostal neurovascular bundle located under the costal groove of the rib above.

For more information, refer to the British Thoracic Society pleural disease guidelines.

Whooping cough is a respiratory infection caused by the bacteria Bordetella pertussis. It is highly contagious and spreads to about 90% of close household contacts. Public Health England (PHE) has identified two priority groups for managing whooping cough contacts. Group 1 includes infants under one year who have received less than three doses of the pertussis vaccine and are at risk of severe infection. Group 2 includes pregnant women at 32 weeks or more, healthcare workers dealing with infants and pregnant women, individuals working with unvaccinated infants under 4 months old, and individuals living with unvaccinated infants under 4 months old.

According to current guidelines, antibiotic prophylaxis with a macrolide antibiotic like erythromycin should only be given to close contacts if the following criteria are met: the index case has had symptoms within the past 21 days and there is a close contact in one of the priority groups. If both criteria are met, all contacts, regardless of age and vaccination status, should be offered chemoprophylaxis. In this case, the mother falls into group 2, so the recommended action is to provide chemoprophylaxis to all household contacts, including the mother, father, and brother. Additionally, those who receive chemoprophylaxis should also consider immunization or a booster dose based on their current vaccination status.

This patient is displaying symptoms of life-threatening asthma, and the only available option for treatment with the correct dosage is an aminophylline loading dose.

The signs of acute severe asthma in adults include a peak expiratory flow (PEF) of 33-50% of the best or predicted value, a respiratory rate of over 25 breaths per minute, a heart rate of over 110 beats per minute, and an inability to complete sentences in one breath.

On the other hand, life-threatening asthma is characterized by a PEF of less than 33% of the best or predicted value, a blood oxygen saturation level (SpO2) below 92%, a partial pressure of oxygen (PaO2) below 8 kPA, a normal partial pressure of carbon dioxide (PaCO2) within the range of 4.6-6.0 kPa, a silent chest, cyanosis, poor respiratory effort, exhaustion, altered consciousness, and hypotension.

The recommended drug doses for adult acute asthma are as follows: 5 mg of salbutamol delivered through an oxygen-driven nebulizer, 500 mcg of ipratropium bromide via an oxygen-driven nebulizer, 40-50 mg of prednisolone taken orally, 100 mg of hydrocortisone administered intravenously, and 1.2-2 g of magnesium sulfate given intravenously over a period of 20 minutes. Intravenous salbutamol may be considered (250 mcg administered slowly) only when inhaled therapy is not possible, such as in a patient receiving bag-mask ventilation.

According to the current ALS guidelines, IV aminophylline can be considered in cases of severe or life-threatening asthma, following consultation with a senior medical professional. If used, a loading dose of 5 mg/kg should be administered over 20 minutes, followed by a continuous infusion of 500-700 mcg/kg/hour. It is important to maintain serum theophylline levels below 20 mcg/ml to prevent toxicity.

For more information, please refer to the BTS/SIGN Guideline on the Management of Asthma.

Legionella pneumophila is a type of Gram-negative bacterium that can be found in natural water supplies and soil. It is responsible for causing Legionnaires’ disease, a serious illness. Outbreaks of this disease have been associated with poorly maintained air conditioning systems, whirlpool spas, and hot tubs. In the past, there have been instances of Legionnaires’ disease outbreaks on cruise ships due to inadequate maintenance of air conditioning and shower units.

The pneumonic form of Legionnaires’ disease presents with certain clinical features. Initially, there may be a mild flu-like prodrome lasting for 1-3 days. A persistent cough, which is usually non-productive and occurs in approximately 90% of cases, is also common. Other symptoms include pleuritic chest pain, haemoptysis, headache, nausea, vomiting, diarrhoea, and anorexia. Additionally, some individuals may experience a condition called syndrome of inappropriate antidiuretic hormone secretion (SIADH), which can lead to hyponatraemia.

It is important to note that infections caused by Legionella pneumophila are resistant to amoxicillin. However, they can be effectively treated with macrolide antibiotics like erythromycin or quinolones such as ciprofloxacin. Tetracyclines, including doxycycline, can also be used for treatment.

Lung protective ventilation is a strategy that involves using smaller amounts of air during each breath (low tidal volumes) and restricting the maximum pressure applied during inhalation (plateau pressure). This approach also allows for a certain level of increased carbon dioxide levels in the body (hypercapnia).

Further Reading:

Mechanical ventilation is the use of artificial means to assist or replace spontaneous breathing. It can be invasive, involving instrumentation inside the trachea, or non-invasive, where there is no instrumentation of the trachea. Non-invasive mechanical ventilation (NIV) in the emergency department typically refers to the use of CPAP or BiPAP.

CPAP, or continuous positive airways pressure, involves delivering air or oxygen through a tight-fitting face mask to maintain a continuous positive pressure throughout the patient’s respiratory cycle. This helps maintain small airway patency, improves oxygenation, decreases airway resistance, and reduces the work of breathing. CPAP is mainly used for acute cardiogenic pulmonary edema.

BiPAP, or biphasic positive airways pressure, also provides positive airway pressure but with variations during the respiratory cycle. The pressure is higher during inspiration than expiration, generating a tidal volume that assists ventilation. BiPAP is mainly indicated for type 2 respiratory failure in patients with COPD who are already on maximal medical therapy.

The pressure settings for CPAP typically start at 5 cmH2O and can be increased to a maximum of 15 cmH2O. For BiPAP, the starting pressure for expiratory pressure (EPAP) or positive end-expiratory pressure (PEEP) is 3-5 cmH2O, while the starting pressure for inspiratory pressure (IPAP) is 10-15 cmH2O. These pressures can be titrated up if there is persisting hypoxia or acidosis.

In terms of lung protective ventilation, low tidal volumes of 5-8 ml/kg are used to prevent atelectasis and reduce the risk of lung injury. Inspiratory pressures (plateau pressure) should be kept below 30 cm of water, and permissible hypercapnia may be allowed. However, there are contraindications to lung protective ventilation, such as unacceptable levels of hypercapnia, acidosis, and hypoxemia.

Overall, mechanical ventilation, whether invasive or non-invasive, is used in various respiratory and non-respiratory conditions to support or replace spontaneous breathing and improve oxygenation and ventilation.

Asthma can be categorized into three levels of severity: moderate exacerbation, acute severe asthma, and life-threatening asthma.

Moderate exacerbation is characterized by an increase in symptoms and a peak expiratory flow rate (PEFR) that is between 50-75% of the best or predicted value. There are no signs of acute severe asthma present.

Acute severe asthma is indicated by a PEFR that is between 33-50% of the best or predicted value. Additionally, the respiratory rate is higher than 25 breaths per minute and the heart rate is higher than 110 beats per minute. People experiencing acute severe asthma may have difficulty completing sentences in one breath.

Life-threatening asthma is the most severe level and requires immediate medical attention. It is identified by a PEFR that is less than 33% of the best or predicted value. Oxygen saturations are below 92% when breathing regular air. The PaCO2 levels are within the normal range of 4.6-6.0 KPa, but the PaO2 levels are below 8 KPa. Other symptoms include a silent chest, cyanosis, feeble respiratory effort, bradycardia, arrhythmia, hypotension, and signs of exhaustion, confusion, or coma.

It is important to recognize the severity of asthma symptoms in order to provide appropriate medical care and intervention.

Ipratropium bromide is a medication that falls under the category of antimuscarinic drugs. It is commonly used to manage acute asthma and chronic obstructive pulmonary disease (COPD). While it can provide short-term relief for chronic asthma, it is generally recommended to use short-acting β2 agonists as they act more quickly and are preferred.

According to the guidelines set by the British Thoracic Society (BTS), nebulized ipratropium bromide (0.5 mg every 4-6 hours) can be added to β2 agonist treatment for patients with acute severe or life-threatening asthma, or those who do not respond well to initial β2 agonist therapy.

For mild cases of chronic obstructive pulmonary disease, aerosol inhalation of ipratropium can be used for short-term relief, as long as the patient is not already using a long-acting antimuscarinic drug like tiotropium. The maximum effect of ipratropium occurs within 30-60 minutes after use, and its bronchodilating effects can last for 3-6 hours. Typically, treatment with ipratropium is recommended three times a day to maintain bronchodilation.

The most common side effect of ipratropium bromide is dry mouth. Other potential side effects include constipation, cough, paroxysmal bronchospasm, headache, nausea, and palpitations. It is important to note that ipratropium can cause urinary retention in patients with prostatic hyperplasia and bladder outflow obstruction. Additionally, it can trigger acute closed-angle glaucoma in susceptible patients.

For more information on the management of asthma, it is recommended to refer to the BTS/SIGN Guideline on the Management of Asthma.