Pneumonia postoperative

The Smdy on the Efficacy of Nosocomial Infection Control (SENIC Project) published in 1981 demonstrated an association between surgery and nosocomial pneumonia (5). In this survey, pneumonias constituted 14% of all nosocomial infections detected among surgical patients, but 74% of all pneumonias occurred in surgical patients (40% of the total study population) (5). 

When comparing data from multiple studies, the specific surgical population and the criteria used to diagnose pneumonia have a great effect on the 

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Hospital-acquired pneumonia The patient developed postoperative pneumonia after a surgical procedure... 

In several studies, transfusion of older compared with fresh erythrocytes has been associated with increased mortality, prolonged hospitalization, intensive care treatment, mechanical ventilation, an increased risk of postoperative pneumonia, infection at any site, and multiorgan failure [21, 22 ]. However, most studies suffered from not adjusting the data for the number of units transfused. Patients who received old erythrocytes often received more cells on average than recipients of fresh erythrocytes. The amount of ceUs transfused reflects the severity of the illness, co-morbidity, and a poorer baseline prognosis [23 ]. A meta-analysis did not support the suspicion that old erythrocytes are associated with common adverse mor-bidity/mortality outcomes [24 ]. 

Conditions required for postoperative pneumonia include a source of bacteria in the oropharynx, a mechanism to allow bacteria to enter the lower airway, and altered pulmonary host defenses to permit infection. Factors associated with postoperative pneumonia are listed in Tables 1 and 2. Risk for pneumonia is associated with preoperative, intraoperative, and postoperative factors tho-... 

Table 2 Factors Associated with Nosocomial Postoperative Pneumonia...

The mechanisms responsible for postoperative pneumonia are similar to the etiologies of other types of nosocomial pneumonia. The most frequent mechanism for bacteria to enter the lower respiratory tract is via aspiration of contaminated oropharyngeal or gastric fluids. Less commonly, organisms can be transmitted via contaminated anesthesia or respiratory therapy equipment or may spread hematogenously from a distant site of infection. As described later, both general anesthesia and postoperative alterations in pulmonary mechanics may increase the likelihood of infection after bacterial contamination of the lower respiratory tract. 

A tracheal aspirate positive for bacteria at the time of surgery is associated with an increased risk of postoperative pneumonia (12,13). In a prospective study of 100 patients undergoing cardiac surgery, a culture was obtained by endotracheal tube immediately after induction of anesthesia and tracheal intubation (12). Lower respiratory tract infection later developed in 8 of 26... 

Use of cardiopulmonary bypass is associated with a greater amount of atelectasis than either anesthesia or sternotomy alone (69). The etiology of the atelectasis after cardiopulmonary bypass has not been elucidated but may be related to the period during bypass when the lungs are not ventilated. The increase in atelectasis after cardiopulmonary bypass may contribute to postoperative pneumonia in patients undergoing cardiac surgical procedures. 

Garibaldi RA, Britt MR, Coleman ML, Reading JC, Pace NL. Risk factors for postoperative pneumonia. Am J Med 1981 70 677-680. 

Martin LF, Asher EF, Casey JM, Fry DE. Postoperative pneumonia determinants of mortality. Arch Surg 1984 119 379-383. 

Ephgrave KS, Leiman-Wexler R, PfaUer M, Booth B, Werkmeister L, Young S. Postoperative pneumonia a prospective study of risk factors and morbidity. Surgery 1993 114 815-821. 

Windsor JA, Hill GL. Risk factors for postoperative pneumonia The importance of protein depletion. Ann Surg 1988 208 209-214. 

Ejlertsen T, Nielsen PH, Jepsen S, Olsen A. Early diagnosis of postoperative pneumonia following upper abdominal surgery. Acta Chir Scand 1989 155 93-98. 

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