A retrospective study of nosocomial pneumonia in postoperative patients shows a higher mortality rate in patients receiving nasogastric tube feeding.

Pneumonia remains a significant cause of morbidity and mortality in surgical patients. Though most studies have focused on pneumonia in trauma or special respiratory intensive care units (ICU), we examine postoperative ventilator-associated pneumonia in patients undergoing elective operations. We hypothesized that a study of multiple clinical variables would disclose factors influencing morbidity and mortality in these patients. We conducted a retrospective review of 1969 patients who underwent elective general, cardiac, and general thoracic procedures during a 6-month period in a private teaching hospital. A total of 77 patients (3.9%) developed postoperative ventilator-associated pneumonia. Thirty-eight (49%) patients had a history of smoking and 27 (35%) had chronic obstructive pulmonary disease (COPD). Among these 77 patients, 20 (26%) experienced recurrent pneumonia. The overall mortality rate for patients developing pneumonia was 34 per cent. At diagnosis of pneumonia, 33 patients were receiving enteral nutrition through nasogastric feeding tubes, whereas 41 received no enteral feeding. The method of nutritional intake was not known in 3 patients. The feeding/nonfeeding groups were similar in age and underlying disease, differing significantly only in the higher number of smokers in the patients not receiving enteral nutrition (P = 0.03). To our surprise, the mortality rate from all causes was higher (P = 0.018) in the patients who received tube feedings through soft, nasogastric feedings (33%) than in those not enterally fed (17%). Parenteral nutrition, COPD, number of ventilator days, and the location of the tip of the feeding tube did not correlate with mortality. The mortality rate from all causes was higher in patients with postoperative pneumonia who received tube feedings, despite similar underlying medical illnesses. Enteral feeding of postoperative surgical patients has many desirable effects, but prospective studies should address harmful effects, such as presumed aspiration and related pneumonia.

Pathogenesis of posttraumatic empyema: the impact of pneumonia on pleural space infections.

BACKGROUND: Thoracic empyema may result either from primary pneumonic sources or intraabdominal sources of infection that seed the pleural space secondarily. In patients with thoracostomy tubes, empyema may result when blood in the pleural space becomes contaminated during tube insertion. To elucidate the cause of posttraumatic empyema, preoperative bronchoalveolar lavage (BAL)/sputum cultures obtained from patients with posttraumatic empyema were compared with cultures obtained at the time of decortication. MATERIALS AND METHODS: A retrospective study was conducted of trauma patients who developed empyema and underwent either video-assisted thoracoscopy or thoracotomy with decortication following blunt or penetrating trauma. At our level I trauma center, we studied all empyema cases diagnosed from November, 1998 to July, 2001. Data collection included patient demographics, injuries sustained, preoperative BAL/sputum cultures, and culture data obtained at the time of decortication. All BAL/sputum cultures were performed no more than 5 days prior to decortication. RESULTS: Thirty-seven patients (26 blunt/11 penetrating) were identified. No patients had concurrent intra-abdominal sources of infection. All patients had at least one chest tube placed prior to decortication. Preoperative respiratory cultures (BAL/sputum) were obtained in 34 patients. The most common organisms isolated were Staphylococcus aureus in six patients (18%) and Hemophilus influenzae in six patients (18%). Intraoperative cultures were obtained in all 37 patients, with the most common organism being S. aureus isolated in 22 patients (60%). Interestingly, a correlation between preoperative BAL/sputum and intraoperative cultures was found in only seven of the 34 patients (21%) who had concomitant respiratory and pleural cultures. Cultures positive for S. aureus were isolated from five patients, Streptococcus pneumoniae from one patient, and Pseudomonas aeruginosa from one patient. CONCLUSION: Little correlation existed between preoperative BAL/sputum cultures and intraoperative cultures in this series of patients with posttraumatic empyema. This suggests that the causation is most often not a parapneumonic process. Furthermore, since S. aureus was the most common organism recovered from empyema, the source was more likely from inoculation of the pleural space by the injury itself or by tube thoracostomy.

Thoracotomy for blunt trauma: traditional indications may not apply.

The indications for performing as urgent thoractomy after trauma are based on the criteria used for penetrating injuries. However, few data are available on the use of these indications for patients with blunt injuries. In a retrospective study (June 1996 to July 2001), we compared the indications of urgent thoracotomy after blunt injury and penetrating injury in patients who underwent thoracotomy within 24 hours of hospital admission at our institution. Patients with blunt aortic injuries or emergency department thoracotomies were excluded from evaluation. Fifty-nine patients were identified (37 penetrating injuries, 22 blunt injuries). Blunt trauma victims had a higher mortality rate than penetrating trauma victims (73% vs. 22%). Chest tube output was the indication for nontherapuetic thoracotomy in 5 patients with blunt injuries whereas this occurred in only 1 penetrating injury victim (P = 0.04). All 5 blunt injury patients underwent a prior procedure and were coagulopathic when thoracotomy was performed. In conclusion, thoracotomy following blunt trauma is associated with a high rate of mortality. The rate of nontherapeutic exploration is increased when chest tube output is the indication for thoracotomy after blunt trauma. Since the majority of such patients have multicavitary injuries that require prior operation and are commonly coagulopathic, caution should be exercised when deciding whether to proceed with thoracotomy based solely on chest tube output.