Exposure to the mechanical ventilation in hospital can also lead to Pneumonia. It makes up a sub type of hospital-acquired pneumonia (HAP) and called as Ventilator-associated pneumonia (VAP).
As the name suggests, VAP only includes the pneumonia infection in hospitalised patients that undergoes mechanical ventilation. It is usually diagnosed by a positive culture after intubation.
The culture is obtained before a patient is put on mechanical ventilation as it helps in categorization of the underlying mechanism or causative agent.
Signs and symptoms of VAP
The signs and symptoms of the patients infected with VAP are not easily visible because the
patients on mechanical ventilation are usually sedated and have limited communication.
Common symptoms of VAP may include the following.
• Low body temperature
• New purulent sputum
Diagnosis of VAP
A diagnosis of VAP is done once the patient has undergone mechanical ventilation.
• Blood Test: Patients who exhibits increasing numbers of white blood cells after putting on mechanical ventilation are susceptible for VAS
• Chest X ray: Patients who show new shadows (infiltrates) on a chest x-ray indicates presence of pneumonia.
• Blood cultures: The infectious agents that cause VAP are identified via blood culture.
• Bronchoscopy: It is an invasive procedure that is used for visualizing the inside of the airways.
• Bronchoalveolar lavage (BAL): It is performed for diagnosing pneumonia in people on ventilators by inserting bronchoscope through the mouth or nose into the lungs. It is followed by inserting fluid in small area of lungs and recollecting it for examination.
Doctors normally follow the below mentioned approaches for diagnosing VAS.
• Collection of cultures from the patient’s trachea and enlarging infiltrate on chest x-ray.
• Using bronchoscopy plus bronchoalveolar lavage (BAL) for patients and enlarging infiltrate on chest x-ray.
Treatment of VAP
The treatment of VAP depends on the causative agent responsible for the infection, however doctors prescribe the antibiotics before detecting the particular bacteria.
• Broad-spectrum antibiotics are given as empiric therapy till the time infectious microorganism is determined.
• Empiric antibiotics take care of local prevalence of resistant microorganisms and previous medical history of patient
• Possible empirical therapy may include the following combinations.
vancomycin/linezolid and ciprofloxacin
cefepime and gentamicin/amikacin/tobramycin
vancomycin/linezolid and ceftazidime
reidopenicillin plus ?-lactamase inhibitor
• Therapy is changed after the causative agents are determined.
• Short-course antimicrobial treatments for VAP patients not infected by nonfermenting Gram-negative bacilli
• Appropriate antibiotics may include levofloxacin, ampicillin/sulbactam, ceftriaxone, and ciprofloxacin.
Prevention of VAP
The prevention of VAP involves the implementation of various strategies.
• Restricting exposure to resistant bacteria
• Discontinuing mechanical ventilation
• Ways for limiting infection during intubation period
• Proper hand washing and hygiene practices
• Sterile technique for invasive procedures
• Individuals with known resistant organisms should be isolated
• Aggressive weaning protocols
• Reducing the amount of sedation received by ventilated person
• Changing the position of bed to make it more comfortable
• Changes in placement of feedings tubes
• Usage of antiseptic mouth washes