Mechanical ventilation for airway support can be a source of infection. It is an important part in intensive care provision for patients who are acutely and critically ill. Although it is beneficial to patients, it can impair the clearance of mucociliary process, causing retention of secretions, occlusion of the airway, atelectasis, and pneumonia.12 Aspiration of orapharyngeal secretions that are contaminated can lead to the development of VAP. These secretions pool above the TT cuff and eventually enter into the lower respiratory tract through the leaking around the cuff of the TT.
Ventilator-associated pneumonia can worsen gas exchange, increase the load of secretions, and can potentially lead to deterioration of the function of other body organs such as the heart. Complications can delay the weaning process, prolong hospital stay, and increase mortality, which can result in higher costs of health care. Ventilator-associated pneumonia is associated with increase in morbidity, MV duration, and length and cost of stay in the hospital. Most hospitals have developed clinical preventive care strategies called the “care bundles,” which showed effective reduction rate in VAP. Many preventive measures such as oral care routine with an antiseptic solution and elevation of the head of the bed are being implemented to prevent VAP. Chlorhexidine oral decontamination is also a widely researched strategy that can help in preventing VAP.
Ventilator-associated pneumonia prevention is a priority to improve patient care and safety. There is a high morbidity and mortality rate that is associated with VAP and in an effort to address this issue, the Centers for Disease Control and Prevention has developed a guideline for preventing VAP. Ventilator-associated pneumonia bundles were implemented to help reduce the incidence of VAP.
DIAGNOSIS OF VAP
Ventilator-associated pneumonia is suspected clinically based on the presence of elevated temperature more than 38.3o C, white blood count more than 10000/mm3 or less than 4000/mm3, purulent secretions, new or persistent pulmonary infiltrate in the chest radiograph, and positive sputum culture and gram stain.10
RESPIRATORY CULTURES
There are many bacterial pathogens that can cause respiratory infections. The major potential respiratory bacterial organisms include Pseudomonas aeruginosa,Staphylococcus aureus, Acinetobacter species, and enteric species.11 A specimen sample from the lower respiratory tract is obtained when VAP is suspected. This involves a specimen collection through suctioning the ETT or TT by using a sterile suction catheter. The specimen is withdrawn and sent to the laboratory for quantitative bacteriology. The presence of more than 10000 colony-forming units per milliliter of target pulmonary respiratory pathogens in minibronchoalveolar lavage fluid or a positive culture is considered to be a positive finding for the diagnosis of VAP.11 As soon as the sputum culture identifies a pathogen and not colonization, specific antibiotic treatment should be initiated.15
CHEST RADIOGRAPH
The presence of pulmonary infiltrates that are not symmetrical on a chest radiograph that is consistent with VAP may be sometimes caused by other noninfectious conditions. However, some chest radiograph findings such as fast cavitation of pulmonary infiltrate that is progressive, air space process that is joining a fissure, bronchogram that is a single air are associated with 96% specific for VAP diagnosis and can be used reliably.