Atelectasis or lung Collapse is defined as incomplete expansion of lung and also
referred to non-aerated lung parenchyma which is otherwise normal. It is called
acquired when a segment, a lobe or lobes collapse(s) after birth (Hazinsk,
This condition which is commonly seen in patients admitted to Pediatric Intensive
Care Unit (PICU) develops as a non-specific complication of many pulmonary diseases.
Lung collapse can deteriorate the general condition of every patient by increased
work of breathing (due to decreased lung compliance), hypoxemia and hypercapnia
(caused by ventilation/perfusion mismatch) and may finally result in acute respiratory
failure. Concern over prolonged atelectasis is that it may worsen hypoxemia
through shunting and may predispose the patient to nosocomial pneumonia (Kreider
and Lipson, 2004).
Treatment of lung collapse may be a major part of general management in a significant
proportion of PICU patients, which can reduce their length of stay in this ward
if it is carried out perfectly (Rozenfeld, 2004) Although
correction of underlying pulmonary disorder is the best treatment of lung collapse,
it is seldom possible; therefore other therapeutic measures and supportive care
are necessary to induce pulmonary re expansion. To gain a perfect clinical response,
one can use invasive (bronchoscopy) or non-invasive medical treatment. Based
on systematic review of Johnston there is No clinical trials to identify the
most efficient treatment for atelectasis in the pediatric patient (Johnston
and Carvalho, 2008). Although bronchoscopy may help to remove mucous plugs
from lower airways in all cases, even more rapidly than non-invasive measures
but that technique is dependent on expensive instruments and highly specialized
human resources which usually are not widely available, therefore we designed
this study to try the efficacy of an incorporated collection of non-invasive
measures as a simple and inexpensive alternative way to re-expand atelectasis,
whether it achieves the same therapeutic results.
MATERIALS AND METHODS
An interventional pre-experimental study was done on 90 patients with lung collapse who were consecutively admitted to PICU of Tabriz Childrens Hospital within a period of 48 months (from March 2004 to February 2008). The followings were inclusion criteria:
||Lack of any clinical evidence for foreign body aspiration
||Presence of clinical evidence for hyper secretion or mucous plug in respiratory
The occurrence of lung collapse and recovery from it was diagnosed upon clinical and radiographic findings. All chest radiograms were reported by the same radiologist who was not aware of this study.
We explained the benefits of this therapeutic method for parents and they permitted us to use it. This method of treatment is consisted of following parts (all ordered as a uniform therapeutic program).
Postural drainage: It means to keep the patient in such a position that places his or her affected lung in the highest part of the chest. Every patient was placed in a proper position by a trained nurse for 90 min, then it was changed into another position for 30 min, therefore the patients position was changing every 2 h to prevent complications of fixed position and restored if changed inappropriately by him or herself.
Chest physiotherapy: This was carried out by a physiotherapist (a technician) using an electrical vibrator or by parents or nurses using chest percussion with a hand for 10-20 min once or twice daily.
Continuous aerosol therapy: We connected a pressurized oxygen reservoir to the fluid chamber of a jet nebulizer, blowing pure O2 as a jet flow of at least 6 litter/minute through that chamber and put them under a hood placed over the patients head. A thin catheter inserted into the fluid chamber of nebulizer which provided it with normal saline, as a continuous refilling line supported by a syringe pump. Therefore every patient continuously (24 h a day) breathes oxygen and aerosol (fluid as floating droplets in air) under hood. Of course, humidification for patients under mechanical ventilation was provided by a humidifier apparatus which vaporized sterile water into inspiratory arm of ventilator tubing set.
Bronchodilator therapy: Because inhalation of every kind of aerosol can induce bronchospasm, salbutamol or epinephrine solution was added to fluid in nebulizer chamber, administered to all patients at a dose of 0.15 mg kg-1 every 4 h. We used salbutamol spray (2 puffs every 4 h) for patients under mechanical ventilation administered through a spacer connected to endotracheal tube.
Ninety patients were studied (47 males and 43 females) with the average age
of 22 months. Nine patients were under mechanical ventilation but the others
(81 patients) didnt need it. Anatomical location of atelectasis has been
shown in Table 1, multiple lobes have been involved in some
instances; however, right upper lobe was the most common involved part of the
lung, which was affected in 73% of all cases. Underlying disorders which caused
lung collapse and their response to treatment by non-invasive methods are showed
in Table 2. The total re expansion rate was 94.5% and average
needed time for relief was 3.4 days, (3.6 days for patients under mechanical
ventilation and 3.2 days for the others).
|| Anatomical location of lung involvement
||Underlying disorders which caused lung collapse and re-expansion
Five out of our 90 patients (4.5%) did not respond to non-invasive treatment of lung collapse, one due to congenital anomaly (stenosis) of bronchus and four because of incomplete treatment due to severe agitation of patient after placing him under hood, both managed by bronchoscopy.
The depth and composition of the airway surface fluid depend on secretion from
the mucous cells and sub mucosal glands and active ion transport across the
surface epithelium as a mechanism for altering the hydration of secretions.
The composition and physical characteristics of airway surface fluid allow for
normal ciliary function and airway hygiene (Fuloria and
Rubin, 2000) and protect the airway from drying. Mucus is transported from
the lower respiratory tract into the pharynx by air flow and mucociliary clearance.
Disruption of normal secretion or mucociliary clearance results in impaired
pulmonary function and lung defense and increased risk of infection (Wanner
et al., 1996). Abnormal respiratory secretions can cause mucus inspissation,
postobstructive atelectasis and airway and parenchymal lung injury with bronchiectasis
and pulmonary fibrosis, leading to severe pulmonary dysfunction.
Lung collapse can be treated in two discrete ways: Medical (non-invasive) and Bronchoscopy or surgical (invasive) treatment. Although bronchoscopy can remove nearly all mucous plugs and re-expand related lung collapse rapidly, but it is not always practical because bronchoscopy or surgical operations are not only invasive but also need trained medical staff and expensive equipments which are not available every where, therefore medical treatment is preferable; as mentioned before about 95.5% of patients recovered completely.
Re-expansion was documented by findings of physical and radiographic examinations).
Bland aerosol administration, which is transference of sterile water or hypotonic,
isotonic or hypertonic saline into airways in the form of aerosol; can be used
not only for treatment of upper respiratory tract disorders, such as laryngotracheobronchitis,
subglottic edema and so on, but also for sputum induction and mobilization of
secretions (Kallstrom, 2003; Dolovich,
1976). Bland water aerosol administration has been used conventionally
as mucolytic and expectorant, although this treatment diminishes the viscosity
of thick secretion in airways and humidifies there, but it has some adverse
effects including bronchospasm and intense cough, therefore bronchodilator inhalation
must be used concomitant therefore Use of inhaled epinephrine for relief of
it will be useful as in asthma (Rau, 2005).
Our international literature review was not very informative because no article
was found in which all components of non-invasive treatment has been studied
as a single protocol. Only in one study, done by Dr. Amirav, who reported that
aerosols are better transferred by hood nebulizer in treatment of 14 infants
(with average age of 8 months) who had wheezing (Amirav
et al., 2003, 2005). According
to the results of our study, aspiration pneumonia with the background of neurological
impairment was the underlying cause of lung collapse in 6 patients; the following
mechanisms may play some role in this process: respiratory muscles weakness,
ineffective cough, accumulation of secretions, chronic aspiration due to convulsion,
dysphagia or reflux and hypo activity or being bed ridden. These mean that neurologically
impaired patients are highly susceptible to lung collapse and need a special
medical attention (Seddon and Khan, 2003).
This study shows that non-invasive medical treatment of lung collapse which mainly consists of postural drainage, chest physiotherapy, aerosol therapy and inhaled bronchodilators administration, is not only scientific and effective but also simple. It can be generalized and substituted for bronchoscopy.