It is well known that patients with traumatic injuries are at increased risk for infection.

The interruption of tissue integrity, hemorrhage and tissue hypoperfusion, frequency of invasive procedures, and impaired host defense mechanisms all have a major impact on subsequent infection [3].

Several factors are implicated in the increased susceptibility of trauma patients to infection, especially in intensive care units (ICU), but identifying independent risk factors for infection in trauma patients is a very difficult task. High ISS scores [4], morbid obesity [5], early hyperglycemia (glucose ≥ 200 mg/dL) [6], the presence of shock or hypoperfusion [7], older age, male gender [8, 9], type of trauma (blunt or penetrating), the number of affected organs, unconsciousness, prolonged mechanical ventilation, spinal cord injury, the requirement for mechanical ventilation, the use of central catheters, multiple transfusions, and several surgical procedures have been reported to be substantial risk factors for infection in trauma patients.

Pneumonia is one of the most common hospital-acquired infections in trauma patients.

Injuries to the thorax, head, and abdomen are associated with a significantly increased risk of pneumonia because of changes in respiratory mechanics [10].

However, the main risk factors for hospital-acquired pneumonias (HAPs) in trauma patients are the use of prolonged mechanical ventilation and positive end-expiratory pressure [11].

Ventilator-associated pneumonias (VAPs) are defined as hospital-acquired pneumonias occurring more than 48 h after patients have been intubated and received mechanical ventilation. VAPs are independently associated with death in less severely injured trauma patients [12].

Early pneumonias within the first few days of hospitalization can also result from aspiration at the time of injury.

HAPs are caused by a wide variety of bacteria that originate from the patient flora or the health-care environment. The most commonly isolated organisms are Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella species, Escherichia coli, Acinetobacter species, and Enterobacter species [13].

Early and appropriate antimicrobial therapy is an essential determinant of clinical outcome. Choosing the appropriate agent, however, remains challenging since in most cases no data on the identity and susceptibility of the pathogen is available at the time of treatment initiation. Because inadequate therapy has been associated with excess hospital mortality from HAPs, the prompt administration of empirical broad-spectrum antimicrobial therapy is essential [14].

Empyemas after trauma can develop after hemothorax, penetrating trauma to the chest, perforation of the diaphragm, contiguous infection, and prolonged chest tube placement.

Empyema is a rare complication. Gram-positive bacteria are the most likely cause after hemothorax.

Prophylactic antibiotics may be administered at the time of chest tube insertion, though this practice is not routinely recommended.

The development of urinary tract infections (UTIs) is mainly related to indwelling urinary catheter use.

These infections are associated with a greater mortality in trauma patients [15].

Escherichia coli is the most frequent species isolated, although it comprises fewer than one-third of isolates. Other Enterobacteriaceae, such as Klebsiella species, Serratia species, Citrobacter species, and Enterobacter species; nonfermenters such as P. aeruginosa; and gram-positive cocci, including coagulase-negative staphylococci and Enterococcus species, are also isolated.

Use of the urinary catheter should always be discontinued as soon as appropriate. A 7–14-day regimen is recommended for most patients with UTI, regardless whether the patient remains catheterized or not.

Data on local antimicrobial resistance, when available, should be used to help guide empirical treatment. Shorter durations of treatment are preferred in appropriate patients to limit development of resistance. Regimens should be adjusted as appropriate depending on the culture and susceptibility results and the clinical course [16].

Resuscitation intravenous lines are a critical part of the care of the trauma patient.

Unfortunately, they are a major source of bloodstream infections.

Central line-associated bloodstream infections (CLABSIs) in critically ill trauma patients are potentially fatal infections and are associated with a substantial increase in long hospital stay and total hospital cost.

Strict adherence to sterile technique can reduce central line-associated bloodstream infections (CLBSIs) and has become a quality improvement measure.

Trauma patients are at higher risk for bloodstream infections than routine surgical patients [17].

Presence of a chest tube, use of immunosuppressive agents, presence of microbial resistance, length of stay, presence of preexisting infection, percentage change of serum albumin levels, patient disposition, transfusion of 10 or more units of blood, and number of central venous catheters (CVCs) were identified as independent predictors of nosocomial BSI [18].