What is Status Asthmaticus & How is it Treated?|Causes, Symptoms, Prognosis of Status Asthmaticus
Status asthmaticus is known to be a medical emergency and it is the extreme form of an asthma exacerbation that can lead to hypoxemia, hypercarbia and secondary respiratory failure. More about the condition, its symptoms, causes, risk factors and treatments are discussed in the following array of the article.
What is Status Asthmaticus?
Status asthmaticus is a medical term used for the most severe form of an asthma attack and it must be noted that in case it happens, you must go to the hospital to get it treated. Your doctor will help you in having an appropriate asthma action plan which you must know so as to prevent or treat yourself. The plan includes things like taking your asthma medicine, avoiding triggers of asthma, keeping up with your doctor appointments and what all to do if your asthma flares up.
If you really have had a bad asthma attack and your rescue inhaler or your nebulizer does not help you, then you need immediate medical attention for this.
Epidemiology of Status Asthmaticus
Asthma affects up to 10% of the population in the United States Of America. Prevalence has increased by 60% in all ages in the past 20 years. Status asthmaticus is usually more common among persons in low socioeconomic groups, regardless of race; as they have less access to regular specialist medical care. Individuals living alone are partially affected.
Causes of Status Asthmaticus
Doctors do not know why some people get such severe asthma attacks. However some of the causes of status asthmaticus might be like
- You do not often see your doctor and so your asthma is not under proper control.
- Not using your peak flow meter and asthma medicines as directed by your doctor in the asthma action plan can cause Status Asthmaticus.
- You frequently come in contact with the triggers of your asthma or things you are allergic to.
Risk Factors of Status Asthmaticus
Severe asthma attacks or status asthmaticus have some risk factors which include the following:
- Gastroesophageal reflux disease is one risk factor for severe asthma.
- Viral infections can also be a cause for status asthmaticus or severe asthma attacks in patients with asthma.
- Air pollutants like dust, industrial pollutants, cigarette smoke etc.
- Cold temperature can also be a risk factor for status asthmaticus.
- Medications like beta-blockers, aspirin and NSAIDs can also cause severe asthma attacks.
- Exercise can also be a risk factor.
A few existing health conditions should be considered as warning signs for Status Asthmaticus and should be kept under regular supervision. Status Asthmaticus happens quickly and rapidly progresses to asphyxiation. According to a few reports and some findings, it has been determined that some of the patients suffering from a poor control of allergens or asthma trigger at their homes or workplaces are more likely to suffer from Status Asthmaticus. These people also have an infrequent use of a peak flow meter and irregular usage of inhaled corticosteroids is also found among these patients. Inhaled steroids are potentially very effective in reducing inflammation associated with asthma.
People diagnosed with Status Asthmaticus may have a history of intubation or hospitalization for asthma. Infrequent health care resulting in poor treatment of asthma is also one of the causes for Status Asthmaticus. People suffering from a poor mental health or psychosocial stressor are at a higher risk of Status Asthmaticus. It is absolutely essential for people with persistent asthma to have an ongoing monitoring of lungs function with peak flow meter.
Pathophysiology of Status Asthmaticus
The respiratory system responds in a particular fashion to each of the components, which are determined from a physiological point of view. After a system has been considerably exposed to an environment possessing allergens, then within minutes mass cell de-granulation can be observed, which goes on simultaneously with the release of inflammatory mediators which includes histamine, prostaglandin D2 and leukotriene C4. The later inflammatory stage has an absolutely different response. With the release of inflammatory mediators, adhesion molecules in the airway epithelium and capillary endothelium primes which then in turn allows inflammatory cells like eosinophils, neutrophils and basophils to get attached to the epithelium and endothelium. After the neutrophils, eosinophils and basophils are attached to the epithelium and endothelium, they one after another move away to the tissues of the airway. Eosinophilic Cationic Protein (ECP) and Major Basic Protein (MBP) are released by eosinophils and both these proteins trigger desquamation of the airway epithelium and expose nerve endings. This interaction promotes further airway hyperresponsiveness in asthma.
People with mild asthma exacerbation may also possess similar type of inflammatory component. What heightens the physical discomfort and makes Status Asthmaticus absolutely life threatening is how the airways resistance increases and how the airway gets blocked due to bronchospasm, mucus plugging and also because of edema in the peripheral airway. A lot of things also happen due to air trapping in the lungs which include: lung hyperinflation, ventilation/perfusion mismatch and increased dead space ventilation. The lung becomes inflated near the end of the pulmonary compliance curve, with decreased compliance and increased work of breathing.
What are the Symptoms of Status Asthmaticus?
There are a lot of symptoms that might indicate that a person might be suffering from Status Asthmaticus. Some of the symptoms are so dangerous that Status Asthmaticus is considered as a medical emergency. Persistent shortness of breath is one of the symptoms of Status Asthmaticus in which a person runs out of breath in spite of living a normal life and not doing any heavy work might suffer from Status Asthmaticus. The symptoms of Status Asthmaticus also include breathlessness while lying down in conventional posture, chest may feel closed and lips might also have a bluish tinge.
Some symptoms of Status Asthmaticus which also matches with symptoms of an impending respiratory system failure include: a feeling of agitation, confusion and inability to concentrate. One might hunch their shoulders, stand up to breathe more easily and also one might strain their abdominal and neck muscles. A significantly higher amount of wheezing and coughing are not always signs of Status Asthmaticus. Medical Experts have gone on to mention that wheezing and coughing are not any significant or reliable standpoint to measure the severity of an asthma attack. The mechanism of inhaling and exhaling are affected so much by a severe asthma attack such as Status Asthmaticus that the lack of air coming in and out of the lungs does not cause any wheezing or coughing. Wheezing does not necessarily indicate asthma, and it can be a sign of a lot of other health conditions such as respiratory infection, heart failure and other serious health issues
Treatments for Status Asthmaticus
After being confirmed about the severity of asthma attack, there would be direct treatments toward controlling bronchoconstriction and inflammation. Bronchoconstriction is the constriction of airways in the lungs due to the tightening of the surrounding muscles with consequent coughing, and shortness or breath etc. Patients with asthma or status asthmaticus suffer from bronchoconstriction and it can be really fatal if not treated.
Let us know about the treatments for status asthmaticus.
Medications and Antibiotics:
Interventions include IV or intravenous medications like magnesium sulfate, aerosolized medications like albuterol or salbutamol for dilating the airways.
In case the patient with status asthmaticus is on a mechanical ventilator, certain sedating medications like propofol or ketamine, must be given which have bronchodilating properties.
It must be noted that routine administration of antibiotics is discouraged. Patients are given antibiotics only when they show evidence of infection, like pneumonia or sinusitis.
In order to treat severe asthma, intravenous corticosteroids and methylxanthines are often given. Corticosteroids are a class of steroid hormones produced in the adrenal cortex of vertebrates and also the synthetic analogues of these hormones.
Hydration with intravenous normal saline at a reasonable rate is required. It is essential to have special attention to the electrolyte status of the patient.
Hypokalemia may result from corticosteroid use while treating status asthmaticus. Correcting the condition may help to wean an intubated patient with asthma from mechanical ventilation.
Oxygen Monitoring and Therapy
Monitoring the oxygen saturation of the patient is essential during the initial treatment of status asthamticus. ABG or Arterial blood gas values are usually used to assess hypercapnia during the initial assessment of the patient. Oxygen saturation in then monitored through pulse oximetry throughout the treatment protocol.
Oxygen therapy is required, with hypoxia being the leading cause of death in children with severe asthma. Oxygen therapy can be administered via a nasal canula or a mask. With the advent of pulse oximetry, oxygen therapy can be easily titrated so as to maintain the patient’s oxygen saturation above 92%.
In the event of significant hypoxemia, non-rebreathing masks may be used for delivering as much as 98% oxygen.
Leukotreine modifiers are essential in treating status asthmaticus, but not acute asthma. This treatment may be beneficial if used via a nebulizer; but it remains experimental. Most studies have examined the intravenous use.
Status asthamticus is usually managed by means of medical therapy, only with some exceptions. For instance, thoracostomy is indicated in pnuemothoraces.
Some children may have asthma that is primarily exacerbated by GERD. Some patients can be treated with a combination of antireflux and histamine 2(H@)- receptor antagonist agents. However, surgery, like Nissen fundoplication, may be occasionally required.
Anesthesia support is required if inhaled anesthetic agents are considered for refractory severe intubated status asthmaticus.
In case all other support modalities fail and extracorporeal membrane oxygenation or ECMO is needed, surgical support for cannula placement should take place at an established pediatric ECMO center for children with severe asthma attacks.
Mortality Rate of Status Asthmaticus
One of the shocking statistics regarding asthma patients is the mortality rate. The mortality rate of asthma patients has increased at an alarming rate. Between 1993 and 1995, the overall annual age-adjusted death rate for asthma increased 40%. What comes out as even more shocking is the fact that the increase in mortality rate among people living in poverty and children aged four years or younger and also among kids aged between 9 and 16 years is even higher. The mortality rate is also particularly higher among patients who delay treatment and arrive for checkup after significant exposure to harmful environment, among patients who delay treatment with systemic corticosteroids.
Status Asthmaticus is a deadly disease for people who already suffer from health conditions existing in their system, such as restrictive lung disease, congestive heart failure, chest deformities, etc. Patients who smoke regularly already have chronic inflammation of the small airways and run a high risk of death from Status Asthmaticus. People of lower socioeconomic status and those with psychiatric illness also have a higher mortality rate according to a recent data. One study links the mortality rate in asthma with the common mold Alternaria Alternata.
Prognosis of Status Asthmaticus
In general, status asthmaticus has a fair prognosis if appropriate therapy is administered and if there is no complicating illness like congestive heart failure or chronic obstructive pulmonary disease present in the patient.
However, it must be mentioned that a delay in beginning the treatment is probably the worst prognostic factor. Patients with acute asthma should use corticosteroids as early as possible.
Now, that you know about some of the causes and also treatment methods for status asthmaticus, you must be wondering if this could be prevented? Well! We must say, that you may not be able to prevent all severe attacks of asthma. However, you can take steps to make them less likely. So, take asthma medication as prescribed by your doctor, avoid asthma triggers, use your peak flow meter several times in a day and visit your doctor from time to time. This is actually very important for you and your doctor to know that you are doing well.