Pneumonia after cardiac surgery is predictable by tracheal aspirates but cannot be prevented by prolonged antibiotic prophylaxis

BACKGROUND: The purpose of this study was to assess the value of tracheal aspirate as a predictor of pneumonia after coronary artery bypass grafting and to evaluate the efficacy of prolonged perioperative antibiotic prophylaxis. METHODS: Tracheal aspirates of 500 patients undergoing coronary artery bypass grafting were taken immediately after intubation and analyzed for microorganisms by Gram stain and semiquantitative microbiologic cultures. All patients received 2 g ceftriaxone as a single-dose perioperative antibiotic prophylaxis before operation. Results of Gram stains were available before the patients were transferred to the intensive care unit. After the results were known, both groups of patients (positive Gram stain, group 1; negative Gram stain, group 2) were randomly assigned to either conventional antibiotic prophylaxis (A), consisting of ceftriaxone 2 g on postoperative day 1, or prolonged antibiotic prophylaxis (B), with ticarcillin + clavulanic acid 3 x 5.2 g during 72 hours. RESULTS: From 500 patients, 91 had a positive Gram stain whereas 409 had a negative one. The incidence of pneumonia was significantly higher in patients with preoperative positive tracheal aspirates (15.3%) than in patients with a negative one (3.6%; p < 0.01). However, prolonged prophylaxis did not reduce the rate of postoperative pneumonia, which was as high as 13% in untreated positive patients versus 17% in treated positive patients, and 2% in untreated negative patients versus 4% in treated patients. In patients who had pneumonia, there was a high correlation between the microorganisms found in preoperative aspirates and those observed when aspirates were repeated (100% correlation in patients with conventional antibiotic prophylaxis and 87% in those with prolonged prophylaxis). CONCLUSIONS: Early postoperative pneumonia (<7 days) is most likely caused by microorganisms that colonize the respiratory tract before operation. The risk of pulmonary infection after coronary artery bypass grafting can be predicted from the preoperative tracheal aspirates. Prolonged perioperative antibiotic prophylaxis has no efficacy in reducing the incidence of pulmonary infections.     

Survival benefit in critically ill burned patients receiving selective decontamination of the digestive tract: a randomized, placebo-controlled, double-blind trial

OBJECTIVE: To evaluate whether selective digestive decontamination (SDD) reduces mortality from any cause, and the incidence of pneumonia among patients with severe burns. SUMMARY BACKGROUND DATA: SDD is a prophylactic strategy to reduce infectious morbidity and mortality in critically ill patients. Two meta-analyses and a recent randomized controlled trial demonstrated a mortality reduction varying between 20% and 40%. But this technique has never been properly evaluated in severely burned patients. METHODS: The design of this single-center trial was randomized, double blind, placebo controlled. Patients with burns > or =20% of total body surface and/or suspected inhalation injury were enrolled and assigned to receive SDD or placebo for the total duration of treatment in the burn intensive care unit (ICU). RESULTS: One hundred seventeen patients were randomized and 107 were analyzed (53 in the SDD group and 54 in the placebo group). The ICU mortality was 27.8% in the placebo group and 9.4% in the SDD group in the burn ICU. Treatment with SDD was associated with a significant reduction in mortality both in the burn ICU (risk ratio 0.25; 95% CI 0.08 to 0.76) and in the hospital (risk ratio 0.28; 95% CI 0.10 to 0.80), following adjustment for predicted mortality. The incidence of pneumonia was significantly higher in the placebo group: 30.8 and 17.0 pneumonias per 1000 ventilation days (P = 0.03) in placebo and SDD group, respectively. CONCLUSIONS: Treatment with SDD reduces mortality and pneumonia incidence in patients with severe burns.     

Selective digestive decontamination: the light as changed from red to green

OBJECTIVES: To study the efficacy of selective digestive decontamination (SDD) for the prevention of nosocomial infections, particularly pneumonia, as well as its impact on the emergence of multiresistant bacteria. DATA SOURCES: Data collected from the Pubmed: original articles, review articles and editorial published on SDD. The keywords were: selective digestive decontamination, pneumonia, intensive care unit, infection. DATA SELECTION: Ten randomized clinical trials performed since 1995 in mechanically ventilated adult patients hospitalized in intensive care unit. RESULTS: The rationale for the use of SDD consists on the parenteral administration of a short course of antibiotic associated with the topical use of non-absorbable antibiotics directed against Gram negative bacteria. Five randomized studies described a reduction in the incidence of pneumonia associated with SDD. Only one study has showed a decrease in mortality rate. The other five studies, which present some methodological limitations, concluded the lack of efficacy of SDD. Regarding the emergence of multiresistant bacteria, the literature underlines the role of environment. The use of SDD seems to trigger the resistance in endemic areas, while these are softened in the units with a good control of their ecology. CONCLUSION: The data from the literature provide arguments to use SDD in targeted patient populations like multiple traumas in intensive care units, which have a low rate of multiresistant bacteria.     

Décontamination digestive sélective chez le malade de réanimation

Nosocomial infections increase morbidity and mortality in hospitalized patients. ICU patients are at high risk of sustaining them, due to the high rate of invasive procedures and their poor health state. Conventional methods for decreasing the incidence of infection in ICU patients include hand-washing, catheter care, strict antibiotic policy, and reduction of environmental sources of infection. Despite these measures, the colonization in these patients is always high, because of the presence of pathogens in the own patients' flora. Nosocomial pneumonia which is a major cause of mortality in ICU patients arises from retrograde colonization of the lung by pathogens originating from oro-pharyngeal and gastric secretions. Since 1984, selective decontamination of the digestive tract (SDD) has been advocated in ICUs to prevent from bacterial and fungal gastrointestinal/oropharyngreal colonization, nosocomial infection, subsequent multiple organ failure (MOF) and death.The SDD regimen is usually an extemporaneously prepared suspension of antimicrobial agents. Appropriate antibiotics for this regimen should ideally be nonabsorbable, to prevent from the development of resistant pathogens and avoid systemic toxicity. They should also be able to selectively eliminate enterobacteriaceae and yeasts, without decreasing the protective anaerobic flora. The most used combination is a suspension of colistin, amphotericin B and aminoglycoside, administered four times day through the nasogastric tube, in association with a paste consisting of 2 p. 100 colistin/amphotericin B/aminoglycoside, applied to the oropharynx. A parenteral antibiotic is also often co-administered during the first four days to prevent from early infections until the SDD regimen reachies its full effect ; cefotaxime is usually used for this. SDD significantly decreases colonization rates in the oropharynx, gastrointestinal (GI) tract and trachea. This effects is primarily attributable to a decrease of Gram-negative bacilli (GNB) and yeasts, although several studies also reported decreased isolates of Gram-positive cocci (GPC). Oropharyngeal and GI colonization significantly decrease after four days of such a regimen, but tracheal decontamination in uncertain. Several studies recognized an emergence of GPC during or after SDD and resistance occurrence in GNB (especially against aminoglycosides). Recolonization occurs rapidly, about 4 to 8 days after the discontinuation of SDD.SDD decreases significantly the nosocomial infections, especially Gram-negative pneumonia. This benefit is most obvious in trauma patients, severely burned patients and after orthopic liver transplantation. Several studies reported a significant decrease in the overall rate of infections, especially extrapulmonary infections, including blood, urinary tract, wounds, abdominal, and catheter related infections. Despite a major decrease in infection rates with SDD, most studies did not show lowered mortality rates. Several studies have reported a reduced mortality rate in selected patient subgroups (trauma patients, ICU stay longer than seven days…). Meta-analyses showed contradictory results. SDD decreases neither the length of stay in the ICU nor the number of days on ventilator. SDD has been used to control nosocomial outbreaks of colonization and infection with multiresistant GNB in ICU, but the results are controversial. In situations leading to MOF and sepsis, as in severe burns, haemorrhagic shock and in endotoxic shock, gut bacteria, especially Enterobacteriaceae, have been demonstrated to translocate into the peritoneal cavity, mesenteric lymph nodes, liver and spleen, finally causing septicaemia. SDD could prevent from gut-originating sepsis by selective elimination of aerobic flora and endotoxin inactivation in the faeces. However these data have been obtained only in rats. The overall cost/effectiveness ratio of SDD use in ICU patients has not been accurately evaluated. In some studies, SDD was associated with a decrease in overall parenteral antibiotic use. In a French multicenter trial, the total costs of antimicrobial agents were 2.2 times higher in ICU patients receiving SDD antibiotics. Therefore additional research is required before SDD regimens can be recommended for routine use in ICU patients. Subpopulations of ICU patients, such as trauma patients may benefit from SDD, but further studies have still to demonstrate the effect of SDD on mortality rate. Research should also be undertaken to determine the effects of SDD on bacterial resistance patterns.     

Routine throat swabs in artificially ventilated patients: meaningful bacteriologic monitoring or a needless procedure?

Organisms colonizing the oropharynx of patients in the intensive care unit (ICU) play an important role in the development of nosocomial infection. Thus, routine throat swab specimens of ICU patients are recommended to screen for potential pathogens [20]. This investigation was designed to clarify the value of throat swabs taken in addition to tracheal aspirates, urine cultures, and wound swabs with regard to antibiotic therapy in patients with pneumonia and other infections. MATERIALS AND METHODS. A total 627 intubated patients were examined in a surgical ICU during a 12 month period. Pharyngeal swabs, tracheal aspirates, urine cultures, and-if necessary-swabs from wounds and drains were taken immediately after admission to the ICU and routinely thereafter three times each week. Definitions: Early onset pneumonia: pneumonia occurring within 4 days; late onset pneumonia: pneumonia occurring after the 4th day. Intra-abdominal infection: diffuse or localized peritonitis or abdominal abscess. Wound infection: soft-tissue or bone infection. Corresponding organisms: the same species of bacteria with the same sensitivity pattern (Table 1). RESULTS. Sixty-eight of the patients developed pneumonia. 37 had early onset pneumonia. In 22 of these patients, throat and tracheal specimens had been obtained 2-3 days before the pneumonia was diagnosed. In these specimens, the causative organisms for the subsequent pneumonia were isolated in the throat in 60% of cases and in tracheal secretions in 40% (Table 3). In 35 patients with late onset pneumonia, the causative bacteria were found in 66% of the cases in the throat swabs obtained 2-3 days before the diagnosis was made, in tracheal aspirates in 74% (Table 4). Throat swabs obtained at admission to the ICU from already infected patients or from patients who developed an infection were significantly more colonized with potentially pathogenic micro-organisms (Fig. 1). In 4 patients with early onset pneumonia the results of the throat swab cultures influenced antibiotic therapy, but none of the throat culture results influenced the therapy of the patients with late onset pneumonia or other infections (intra-abdominal infection, wound infection, urinary tract infection). CONCLUSIONS. The throat swab taken at admission may indicate patients at risk for infection. However, throat cultures taken routinely thereafter, parallel with tracheal aspirate cultures, do not provide additional information that is diagnostically or therapeutically helpful. Therefore, throat swab cultures are not necessary for routine bacteriological monitoring. For the prevention of colonization by local administration of antimicrobial agents, regular throat cultures are mandatory.     

The effect of oropharyngeal decontamination using topical nonabsorbable antibiotics on the incidence of nosocomial respiratory tract infections in multiple trauma patients

The incidence of respiratory tract infections was determined in 59 multiple trauma patients requiring prolonged intensive care (greater than 5 days) and receiving no antibiotic prophylaxis. Early pneumonia (less than 48 hr) with S. aureus, S. pneumoniae, and/or H. influenzae was found in 44% of patients. Secondary colonization of the oropharynx and respiratory tract with ICU-associated Gram-negative bacilli followed by pneumonia occurred in 12 patients (20%). The overall incidence of respiratory tract infections was 59%. In a prospective open trial three prophylactic antibiotic regimens were compared: 17 patients were treated with intestinal decontamination using nonabsorbable antibiotics (polymyxin E 400 mg, tobramycin 320 mg, amphotericin B 2,000 mg/day). No difference in infection rate was found. Twenty-five patients were treated with intestinal and oropharyngeal decontamination using an ointment containing 2% of the same antibiotics. Secondary colonization and infection of the respiratory tract with Gram-negative bacilli was significantly reduced (p less than 0.001). The incidence of early (Gram-positive) infections, however, was unchanged. Another group of 63 patients was treated with systemic antibiotic prophylaxis during the first days in combination with oropharyngeal and intestinal decontamination. The incidence of early pneumonia was significantly reduced (p less than 0.001). Five patients (8%) developed an infection. Superinfections were not observed.     

Effectiveness of topical selective decontamination, without systemic antibiotic prophylaxis, in prevention of pulmonary infection in intensive care

Forty-seven patients admitted in our general ICU and treated with Selective Digestive Decontamination (SDD) without any systemic antibiotic prophylaxis, were prospectively studied and compared with an historical group of 50 non treated subjects. The 2 groups were no different as to underlying disease, age, sex and prognostic index (SAPS). In the treated group was recorded an important and statistically significant reduction in the incidence of pneumonia and in the frequency of pulmonary infections caused by enterobacteriaceae and pseudomonceae. Gram-positive identification in tracheal aspirates was not significantly different in the two groups as well as the incidence of "early pneumonia". In the treated group, a sharp decrease of the total amount of fever-days through ICU stay was observed. The antibiotic consumption resulted to be an overall 28.3% lower in the group treated with, SDD with particular regard to broad-spectrum ones.     

Selective decontamination of the digestive tract: a stratified, randomized, prospective study in a mixed intensive care unit.

To evaluate the use of selective decontamination of the digestive tract (SDD) (polymyxin, amphotericin, tobramycin, and intravenous cefotaxime) in a mixed intensive care unit, we performed a stratified, randomized, prospective study. The 331 patients were recruited over an 18-month period, with 256 patients remaining more than 48 hours. Stratification by acute physiology and chronic health evaluation (APACHE II) preceded randomization to control (standard antibiotic therapy) or treatment (SDD) groups. Nosocomial infection was significantly reduced in the SDD group (16.7%; 21 of 126 patients) compared with the control group (30.8%; 40 of 130 patients; p = 0.008). No difference was found in overall mortality rate or length of stay between the two groups. Those patients with admission APACHE II scores 10 to 19 demonstrated the most significant reduction in nosocomial infection (23 of 70 control vs 13 of 76 SDD; p = 0.03) and mortality (15 of 70 control vs 8 of 76 SDD; p = 0.07). Emergence of multiresistant microorganisms was not a clinical problem, but a definite change occurred in the ecology of environmental and colonizing bacteria. With the exception of cefotaxime, a reduction was noted in systemic antibiotic usage in the SDD group. We conclude that SDD is useful in selected patients in a mixed intensive care unit.     

Prevention of bacterial infection and sepsis in acute severe pancreatitis.

Between 1984 and 1986 six patients with acute respiratory failure (requiring ventilation for at least 3 days) complicating acute pancreatitis were managed on the intensive care unit (median ventilation period 6 days; range 3-41 days). Between 1987 and 1989 nine similar patients were managed (median ventilation period 35 days, range 4-69 days), and a regimen of enteral tobramycin, polymyxin and amphotericin to selectively decontaminate the digestive tract (SDD) was introduced. Five of six patients treated before 1987 had serious infections (three Gram-negative, one fungal), compared with only one of nine patients treated with SDD (P < 0.05). Clinical signs of sepsis were evident for 62% of the pre-SDD period, compared with 39% of the period during SDD therapy (P < 0.001). Systemic antibiotic prescribing was reduced in the SDD group; however, mortality remained unaffected with only two patients surviving pre-SDD and three during SDD treatment. SDD reduces infection rates and sepsis in patients with acute pancreatitis and may help to improve the prognosis of this life-threatening condition.     

Prophylactic antibiotics alter the bacteriology of infected necrosis in severe acute pancreatitis

BACKGROUND: Use of appropriate prophylactic antibiotics has been shown to decrease infectious complications and mortality rate in patients with severe acute pancreatitis, but its influence on the bacteriology of secondary pancreatic infection is poorly defined. STUDY DESIGN: Operative cultures from 61 consecutive patients with pancreatic necrosis treated during routine prophylactic antibiotic use (1993-2001) were compared with 34 consecutive patients with necrosis treated before routine antibiotic use (1977-1992). RESULTS: The two groups of patients were similar in demographics, etiology of pancreatitis, and severity of illness. All patients in the antibiotic group received prophylactic antibiotics compared with only 38% (13 of 34) in the control group. Routine broad-spectrum prophylactic antibiotics altered the bacteriology of secondary pancreatic infection in severe acute pancreatitis from predominantly gram-negative coliforms (56% versus 26%, p = 0.005) to predominately gram-positive organisms (23% versus 52%, p = 0.009) without a significant increase in either the rate of beta-lactam resistance or fungal infections. The overall hospital stay in patients treated with prophylactic antibiotics was significantly reduced (61 +/- 24 days versus 41 +/- 28 days, p = 0.002), and there was a trend toward a decline in mortality rate in the antibiotic treatment group. CONCLUSION: Routine broad-spectrum prophylactic antibiotic use has altered the bacteriology of secondary pancreatic infection in severe acute pancreatitis from predominantly gram-negative coliforms to predominantly gram-positive organisms without altering the rate of beta-lactam resistance or fungal superinfection.     

Diagnosis, management and prevention of ventilator-associated pneumonia in the UK

BACKGROUND AND OBJECTIVE: Ventilator-associated pneumonia is a nosocomial infection that occurs in patients receiving mechanical ventilation for >48 h. Many aspects of its diagnosis, treatment and management are controversial. We used a postal questionnaire to survey current practice within the UK. METHODS: Questionnaire study of 207 general intensive care units in the UK. RESULTS: The response rate was 77.3%. Regarding diagnosis, 30% of units obtained specimens from the lungs invasively, while the remainder relied on tracheal aspirates. In only 28.2% of units using tracheal aspirates were results reported in a quantitative manner. A clinical suspicion of ventilator-associated pneumonia would lead to the administration of empirical antibiotic therapy in the majority of units (77.2%), opinion being almost equally divided on whether this should be mono (49.1%) or combination therapy (50.9%). Although most units received regular microbiology feedback (90.5%), the involvement of a microbiologist in the antibiotic decision-making process was variable. Antibiotics were continued for a median of 7 days (inter-quartile range 5-8.5, range 2-14 days). Compliance with the principal methods of ventilator-associated pneumonia prevention was good. CONCLUSION: There is widespread variation in the methods used for the diagnosis of ventilator-associated pneumonia within the UK. The majority of units rely on non-quantitative analysis of tracheal aspirates. This technique has a high percentage of false-positives, and suggests widespread over utilization of antibiotics. However, most agree that antibiotics should be given empirically when there is a clinical suspicion of ventilator-associated pneumonia. The widespread introduction of 'ventilator bundles' appears to have ensured that most units actively take measures to prevent ventilator-associated pneumonia.     

Use of selective decontamination of the digestive tract in United Kingdom intensive care units*

The use of selective decontamination of the digestive tract (SDD) remains controversial despite several large randomised‐controlled trials and meta‐analyses. A postal survey of intensive care units in the United Kingdom was conducted to document current use of SDD, and to identify factors influencing this practice. The response rate was 71%. The vast majority (182 units, 95%) do not use SDD mainly because practising clinicians do not believe it works or that there is not enough evidence (51%), and because of concerns about antibiotic resistance (47%). Of the 10 units using SDD, three apply it to all intubated patients and five do not use intravenous antibiotics in their protocol.     

新生儿重症监护病房医院感染的危险因素分析

目的：通过对新生儿重症监护病房医院感染病例的危险因素进行回顾性分析,为预防和控制新生儿医院感染提供科学依据。方法收集本院新生儿重症监护病房2008年1月至2012年6月收治的1186例患儿资料,对确诊为院内感染患儿的流行病学资料、住院期间的临床资料及实验室相关检测结果进行回顾性分析。结果1186例新生儿患者中有85例患儿存在医院感染,医院感染发生率为7.17%;病原菌以革兰阴性菌最多见（53/85,62.4%）,主要为肺炎克雷伯菌（18/85,21.2%）、鲍曼不动杆菌（12/85,14.1%）、铜绿假单胞菌（7/85,8.2%）和大肠埃希菌（5/85,5.9%）。本组病例院内感染的临床表现以肺炎（35/85,41.2%）最为常见,其中呼吸机相关性肺炎占所有肺炎的68.6%（24/35）;其次为败血症（22/85,25.9%）和腹泻（12/85,14.1%）。多元Logistic回归分析结果显示,机械通气（OR=1.921）、脐静脉置管（OR=1.301）、住院时间（OR=1.076）、胎龄（OR=1.125）和胎膜早破（OR=1.207）等是新生儿发生院内感染的主要危险因素。结论新生儿院内感染的病原菌以革兰阴性菌为主;缩短机械通气和住院时间,尽早拔除静脉置管可降低新生儿院内感染发病率。     

New epidemiology for postoperative nosocomial infections

Changes in health care delivery systems over the last decade have resulted in a major increase in outpatient surgery and a higher severity of illness for inpatients. We sought to determine the effects of this change on the epidemiology of postoperative surgical infections. Historical data on incidence and epidemiology of infection were obtained from peer-reviewed articles published between 1960 and 1999 (MEDLINE). All nosocomial infections in 5035 patients admitted to a tertiary-care university hospital surgical intensive care unit between January 1994 and December 1997 were prospectively identified and classified as wound, urinary tract, bloodstream, or pneumonia. Incidence of bacterial isolates at each site was also recorded. From these data we determined infection rates per 100 admissions. We also identified all device-related nosocomial infections and calculated infection rates. Comparisons between time periods were made. In the 1960s wound infections constituted the predominant postoperative infection at 46 per cent. This was replaced by urinary tract infection in the 1970s (44%) and 1980s (32%) and closely followed by bloodstream infections (25%). In the 1990s nosocomial pneumonia became the most common postoperative infection, comprising 43 per cent of surgical intensive care unit infections. Analysis of the bacteriology also revealed changing trends with primarily gram-positive organisms in the 1960s followed by an increase in methicillin-resistant Staphylococcus in the 1970 to 1980s, and currently resistant gram-negative bacteria predominate. The incidence of fungal infections has steadily increased. This survey identified a new epidemiology for postoperative surgical infections. Over the last several decades the reported wound infections have been markedly decreased and there is little change in urinary tract infection. Nosocomial pneumonia with resistant gram-negative bacteria now predominates along with increased incidence of fungal infections. Currently, postoperative infections are now more severe, involve critical organs, and require close monitoring of the changing patterns of pathogens.     

Impact of initial antibiotic therapy on the course of resistance to fluoroquinolones and aminoglycosides in Gram-negative bacilli isolated from intensive care patients

OBJECTIVE: To evaluate the effect of the initial antibiotic therapy associating a betalactam antibiotic (BLA) with either an aminoglycoside (AG) or a fluoroquinolone (FQ) on the development of resistance of gram-negative bacilli in an intensive care unit. STUDY DESIGN: Prospective bacteriological surveillance study. PATIENTS: The study included 51 patients experiencing a second infection with gram-negative organisms, eight days or more after a first infection. METHOD: The incidences of bacterial infection and the antimicrobial susceptibility have been assessed. RESULTS: The first-choice therapy was based either on BLA + AG (51%), or on BLA + FQ in the others (46%). The causative organisms were Enterobacteriaceae (57%) and Pseudomonas aeruginosa (31%). The second infection occurred 23 +/- 11 days after the first. The main organisms involved were Pseudomonas aeruginosa (51%) and Enterobacteriaceae (41%). In the group treated initially with an AG, only the antibiotic susceptibility for amikacin decreased significantly (72 vs 36%, p < 0.05). The latter was the most prescribed antibiotic (56%). In the FQ group, there was a significant decrease of susceptibility for ciprofloxacin, pefloxacin, netilmicin and tobramycin. The decrease was not significant for gentamicin and amikacin. CONCLUSIONS: In intensive care patients, the use of FQ in association with a BLA increases the resistance to AG and FQ. Therefore it seems preferable to administer an AG in association with a BLA. Amikacine should only be prescribed when justified for a given case.     

Bacterial pneumonia in ventilated patients. The role of bronchoalveolar lavage in diagnosis and therapy

In the diagnosis and treatment of bacterial pneumonia, the isolation and resistance pattern of the causative organisms are very relevant. Bronchoalveolar lavage (BAL) with quantitative culture is the best technique to obtain material for bacteriological investigations in nonintubated medical patients and in a baboon model. The present study was designed to clarify the following questions: What is the value of BAL compared to tracheal secretion (TS) in ventilated patients with regard to antibiotic therapy? Is it possible to distinguish colonization and infection by investigation of BAL? MATERIAL AND METHODS. In 34 ventilated patients, we studied the diagnostic and therapeutic value of BAL in comparison to TS. Thirteen patients suffered from pneumonia, 9 patients were colonized, and in 12 pneumonia was uncertain. These terms are defined as follows: 1. Pneumonia: temperature over 38.5 degrees C, leukocyte count over 12,000/mm3, infiltrate in the x-ray compatible with pneumonia, purulent tracheal secretion, positive bacteriological findings. All criteria must be fulfilled. 2. Colonized patients: mechanical ventilation more than 7 days, no signs of infection, isolation of the same bacteria species in two previously obtained tracheal secretions. 3. Uncertain pneumonia: not all criteria mentioned above were fulfilled. BAL was performed in the usual manner. The bronchoscope was wedged into a distal airway and 6 x 20 ml of sterile, nonbacteriostatic saline (0.9% NaCl) was instilled through the suction channel and subsequently aspirated. All investigation materials were immediately processed in the bacteriological laboratory. From the BAL specimen Giemsa and Gram preparations were performed to look for contamination from the throat and intracellular bacteria. RESULTS. Patients with pneumonia: In all patients the TS and BAL were positive. Cultures from BAL and TS were in agreement in 77% of the cases. In 10 patients intracellular bacteria (BAL) were present, in two patients the Gram preparation was nonapplicable because of destroyed cells. In one patient Haemophilus spp. could be isolated in the BAL (10(5)/ml BAL), but not in TS, which definitely influenced therapy. Colonized patients: In all patients TS and BAL were positive, with exact agreement in 33% of the cases. The concentration of isolated bacteria (BAL) was not as high in these patients as in the patients with pneumonia (median: 8 X 10(3) vs 6 X 10(4]. However BAL allowed no differentiation between colonization and infection in individual cases. Uncertain pneumonia: TS was positive in 8 patients, no TS could be obtained in 4. BAL was sterile in 4. Only in 2 bacteria greater than or equal to 10(4)/ml were isolated and both patients had intracellular bacteria. The results (BAL) influenced therapy in 5 cases (4 patients received no antibiotics; in 1 patient the antibiotics were modified). CONCLUSION. BAL is very helpful in patients suspected of having pneumonia and in sepsis of unknown origin when pneumonia should be excluded...     

Therapy of infection

The five basic principles behind the concept of the treatment of an established infection are as follows:

• •surveillance and diagnostic cultures to ensure identification of the micro-organism so that modification of the otherwise ‘blind’ treatment can be undertaken;
• •immediate and adequate antibiotic treatment in order to sterilize the infected internal organs;
• •the source of potential pathogens causing the infection — whether endogenous or exogenous — requires elimination for both the recovery of the original infection and the prevention of relapses and/or superinfections. Selective decontamination of the digestive tract (SDD) aims at the eradication of of the oropharynx and gut in patients, whilst identification and eradication of the outside the patients, using disposables and/or hygiene, are an integral part of the therapy of infection;
• •removal or replacement of invasive devices often contaminated with the potential pathogen is thought to contribute to the healing in curtailing the supply of micro-organisms;
• •surveillance samples are indispensable in evaluating the efficacy of this five component protocol.

The treatment of practically all infections relies on these five basics, in particular lower airway and blood stream infections developing in the critically ill requiring intensive care including mechanical ventilation. Special attention is given in this chapter to the underestimated problem of exogenous infections due to intensive care unit (ICU) associated bacteria without preceding carriage, and to the increasing problem of the serious infections caused by methicillin-resistant Staphylococcus aureus (MRSA).     

Nosocomial colonisation and infection in a paediatric respiratory intensive care unit.

A study of the prevalence of nosocomial colonisation and nosocomial infection (NI) was conducted in the paediatric respiratory intensive care unit of a large teaching hospital serving a developing community. Surveillance specimens were collected regularly from 63 consecutive patients admitted over 4 months, and also from professional staff, boarder mothers, cleaners and the unit environment. The incidence among patients of colonisation (40%) and of NI (43%) was high. The risk of dying in children with NI was appreciably increased (relative risk 2,241, confidence interval 0,591-8,503). This did not reach statistical significance, probably because so few children escaped acquiring hospital organisms. The significant risk factor for acquiring colonisation (P = 0.008) and NI (P < 0.0001) was a ward stay of more than 10 days. In addition, for acquiring NI an age of under 6 months was also predictive (P = 0.0298). The nature of the primary illness dictated the time spent in the ward; an important proportion of patients had preventable diseases, such as measles, pneumonia and tetanus, which required prolonged treatment. All children with endotracheal intubation had hospital-acquired organisms in tracheal aspirates. Eighty-two per cent of children developed positive gastric aspirates, 17% a positive urine culture and 11% a positive blood culture. Colonisation occurred rapidly; organisms initially appeared in gastric aspirates (mean 2 days), then in tracheal aspirates (mean 5 days) and urine cultures (mean 10 days). The acquired organisms, many of which were antibiotic-resistant, were almost exclusively enteric Gram-negative bacilli (GNB) and Staphylococcus aureus.(ABSTRACT TRUNCATED AT 250 WORDS)     

Sex hormone binding and peritumoural oedema in meningiomas: Is there a correlation?

Summary 136 patients older than 70 years, admitted to our neurosurgical ward directly after head trauma, were analysed. 40% of them were admitted with low GCS, below 9 points, and showed a mortality of 85%. 45 patients had intracranial mass lesions — the commonest was subdural haematoma, with a low incidence of epidural haematomas. In patients admitted with GCS above 12, mortality was 20%, mainly due to pneumonia. Satisfactory results were achieved in 30% of trauma victims. From patients with intracranial space occupying lesions and GCS below 9 points on admission practically all died, despite aggresive surgical treatment and intensive care. Thus, especially in departments with limited resources, therapy can be limited, or even no therapy may be introduced in this group. Surgical treatment can be limited only to patients who are conscious on admission. In patients with non-surgical lesions, low GCS — below 9 points — leads to mortality of 80%, and in this group we propose aggresive intensive care for 24 hours and the limitation of further maximal therapy only to those, who significantly improve within this period of time. If the patient has a non-surgical lesion and is conscious after trauma, aggresive treatment of extracranial complication is the most important, because brain injury can usually be well tolerated by these patients. If pneumonia or heart complications do not occur this group of old patients often have a good prognosis.