Outcomes of Acinetobacter baumannii infection in critically ill surgical patients

BACKGROUND: Multi-drug resistant (MDR) organisms in intensive care units (ICUs) are a growing concern. The emergence of several infections with MDR Acinetobacter baumannii prompted a review of cases and evaluation of the efficacy of intervention. OBJECTIVE: To determine the rate of clinical cure, the incidence of drug resistance, and the mortality rate associated with A. baumannii infection. METHOD: Retrospective review of A. baumannii infections in three surgical ICUs between January, 2004 and November, 2005. Infection was identified in 291 patients, 20 of whom were excluded because of incomplete documentation. Of the remaining 271 patients, 71% were male, and the mean age was 47 +/- 18 years (range 13-90 years). RESULTS: Patients had a mean length of stay in the ICU of 14 days (range 0-136 days) before infection. The initial positive cultures were from bronchoalveolar lavage fluid (BAL) in 72.3%, blood in 16.2%, a catheter tip in 6.3%, urine in 1.8%, wound in 2.2%, and abscess in 1.1%. In 46.9% of patients, the first culture was polymicrobial. The Acinetobacter isolates were resistant or intermediate-resistant to imipenem-cilastatin in 81.2% of cases; 19.9% were resistant to all drugs except colistin, and two were resistant to all tested drugs. Colistin was used in 75.6% of patients (intravenous 61.5%, nebulized 38.5%). The mean duration of treatment was 13 +/- 8.9 days (range 0-56 days), and clinical cure was achieved in 73.8% of patients. Recurrent infection after initial cure was found in 19.2% of patients. There was no significant difference in clinical cure rates between patients treated with colistin and those treated with other culture-directed drugs (75.1% vs. 69.7%), or between patients treated with intravenous vs. nebulized colistin (72.4% vs. 79.5%). The mortality rate was 26.2% for the entire group and was significantly higher in the subgroup of transplant patients (n = 31) (64.5% vs. 21.4%; p < 0.001). CONCLUSION: The majority of A. baumannii isolates were MDR, and a significant proportion were sensitive only to colistin. Treatment of A. baumannii infection with colistin is effective by both intravenous and nebulized routes of administration. However, infection with A. baumannii in critically ill surgical patients is associated with a high mortality rate, particularly in transplant patients.     

Preventing strategy of multidrug-resistant Acinetobacter baumanii susceptible only to colistin in cardiac surgical intensive care units

OBJECTIVE: The study aimed to determine the incidence and mortality of multidrug-resistant Acinetobacter baumannii in cardiac surgery, to elucidate the effectiveness of colistin treatment and to identify if the additional measures to the recommended procedures were able to control the dissemination of the pathogen. METHODS: A prospective observational cohort was conducted among cardiac surgical patients from 1 September 2005 to 31 December 2006. We reviewed the prophylactic measures of the surgical intensive care unit and implemented a two scale multiple program. Scale I included classical infection control measures, while Scale II referred to the geographic isolation of multidrug-resistant Acinetobacter baumannii patients and environmental intense surveillance. RESULTS: Among 151 out of 1935 infected patients 20 were colonized and infected by strains of multidrug-resistant A. baumannii susceptible only to colistin. Seventeen patients presented respiratory tract infection, one patient suffered deep surgical site infection and two patients catheter related infection. Transmission of the pathogen occurred via two patients transferred from two other institutions. They were all treated with colistin. Cure or clinical improvement was observed only in four patients (20%). Scale I measures were implemented for the whole 16-month period while scale II for two separate periods of 3 weeks. Environmental specimens (n>350) proved negative. CONCLUSIONS: The increasing prevalence of multidrug-resistant A. baumannii in surgical intensive care unit patients creates demand on strict screening and contact precautions. Following this infection control strategy we were able to achieve intermittent eradication of the pathogen during a 16-month period with continuous function of the intensive care unit. Despite the significant in vitro activity of colistin against multidrug-resistant Acinetobacter baumannii the results were discouraging.     

Antiseptic-bonded central venous catheters and bacterial colonisation

This study was undertaken to evaluate the impact of chlorhexidine/silver sulphadiazine-bonded catheters on the incidence of colonisation and catheter-related sepsis in critically ill patients. Threehundred and fifty-one catheters were inserted into 228 patients during the study period, 174chlorhexidine/silver sulphadiazine-bonded catheters and 177 standard catheters. Indications for catheter removal were: death, clinical redundancy and clinical evidence of local or systemic infection. All catheter tips were sent to the microbiology laboratory for semiquantitative analysis of bacterial colony count. Seventy-one (40.2%) of the standard catheters and 47 (27.2%) of the antiseptic-bonded catheters were found to be colonised on removal (p < 0.01). Eight cases (4.7%) of catheter-related sepsis were associated with standard catheters and three cases (1.7%) with antiseptic-bonded catheters, however, this reduction was not statistically significant. Our results indicate that the use of antiseptic-bonded catheters in critically ill patients significantly reduces the incidence of bacterial colonisation.     

Glucose in bronchial aspirates increases the risk of respiratory MRSA in intubated patients

BACKGROUND: The risk of nosocomial infection is increased in critically ill patients by stress hyperglycaemia. Glucose is not normally detectable in airway secretions but appears as blood glucose levels exceed 6.7-9.7 mmol/l. We hypothesise that the presence of glucose in airway secretions in these patients predisposes to respiratory infection. METHODS: An association between glucose in bronchial aspirates and nosocomial respiratory infection was examined in 98 critically ill patients. Patients were included if they were expected to require ventilation for more than 48 hours. Bronchial aspirates were analysed for glucose and sent twice weekly for microbiological analysis and whenever an infection was suspected. RESULTS: Glucose was detected in bronchial aspirates of 58 of the 98 patients. These patients were more likely to have pathogenic bacteria than patients without glucose detected in bronchial aspirates (relative risk 2.4 (95% CI 1.5 to 3.8)). Patients with glucose were much more likely to have methicillin resistant Staphylococcus aureus (MRSA) than those without glucose in bronchial aspirates (relative risk 2.1 (95% CI 1.2 to 3.8)). Patients who became colonised or infected with MRSA had more infiltrates on their chest radiograph (p<0.001), an increased C reactive protein level (p<0.05), and a longer stay in the intensive care unit (p<0.01). Length of stay did not determine which patients acquired MRSA. CONCLUSION: The results imply a relationship between the presence of glucose in the airway and a risk of colonisation or infection with pathogenic bacteria including MRSA.     

Dry ice cryoamputation: a twelve-year experience

Amputation done on an emergency basis of severely ischemic or infected limbs in critically ill patients frequently results in increased morbidity and mortality. To evaluate the effect of delaying an inevitable operative amputation by a simplified method of freezing the involved extremity, the records of 56 patients who underwent preoperative cryoamputation during a 12-year period were reviewed. Data concerning risk factors, associated medical conditions, local or systemic signs of sepsis, level of amputation, morbidity, and mortality were analyzed. Following cryoamputation of 57 limbs, 16 above-knee amputations (AKA) and 41 below-knee amputations (BKA) were performed. The overall mortality rate associated with cryoamputation was 14% (8 of 57); four postoperative deaths occurred in both the AKA and BKA groups. The mortality rate for 1021 primary operative major amputations during the same period was 7% (p less than 0.04). The only factor identified that significantly affected survival following cryoamputation was diabetes mellitus, which was present in 68% of surviving patients and in 12% of those who died (p less than 0.001). This experience suggests that cryoamputation is a valuable, simple technique that allows for deliberate stabilization and preparation of seriously ill, septic patients prior to surgical procedures, which, when performed on an emergency basis have been associated with mortality rates exceeding 40%.     

MRSA: predictor of outcome in critically ill patients

Methicillin resistant Staphylococcus aureus (MRSA) infectionin critically ill patients is associated with considerable morbidity,mortality and cost.^{1 2} In 1994, we studied 29 MRSA positivepatients admitted to the intensive care unit (ICU). Althoughthe size of population studied was too small to be conclusive,there was a suggestion that MRSA did not have a significantimpact on overall mortality (unpublished observation), however,there was an increase in average length of stay. In this retrospective study, microbiology records identifiedMRSA infected/colonised patients admitted to ICU over 36 months(1996–1998). Patient demographics, site of isolation andhospital mortality were recorded. Isolation of MRSA from blood,sterile sites or endotracheal secretions was considered to bea surrogate marker of serious infection. In those patients withMRSA isolated in multiple sites, the most likely site for seriousinfection was selected. One hundred and sixty seven patients were found to be infected/colonizedwith MRSA and of these 59 patients had positive blood or sputumcultures. Hospital mortality of MRSA positive patients was 50.9%compared to 33.8% overall hospital mortality of all ICU patients.Standardized incidence ratio for death was 1.51 (95% confidenceinterval 1.20–1.86) for patients with MRSA. As expectedthe number of deaths rises with age (60 yr was 34.8%, 61–75yr 52.6%, >75 yr 64.4%. Odds ratio 2.74 (95% confidence interval1.09–6.93) for >75 compared with 60 yr old). Diagnosis of MRSA from blood and sputum (group A) had a mortalityof 44.1%, compared to 51.3% in those with MRSA from screeningsites (group B) (P=0.403). Whilst mortality increases with agefor both groups, it rises faster in patients with MRSA in groupB (Table 7). There was no difference in mortality between groups. The poorassociation between mortality and positive blood or sputum culturescorroborates our previous observation that detection of MRSAis more likely to be an indicator of poor prognosis rather thanthe cause of fatal infection.     

Impact of obesity in the critically ill trauma patient: a prospective study

BACKGROUND: Obesity has risen at an epidemic rate over the past 20 years in the US. To our knowledge, there is an absence of data evaluating the impact of obesity in the critically ill trauma patient. METHODS: Prospective data were collected on 1,167 patients admitted to the ICU over a 2-year period. Obesity was defined as a body mass index (calculated as weight [kg]/height [m(2)]) of 30 or higher. Outcomes analyzed included infection rate, hospital and ICU length of stay, and mortality. Multiple logistic regression was used to evaluate outcomes between obese and nonobese patients for infection (infection versus noninfection) and mortality (deceased versus not deceased). Continuous outcomes such as hospital and ICU lengths of stay were evaluated using multiple linear regression analyses. RESULTS: Sixty-two of 1,167 (5.3%) patients were obese. The majority (71%) of injuries in the study cohort were blunt. Although the majority of patients were men (76%), women (10% versus 4%) were more likely to be obese (p < 0.001). Obese patients had a more than twofold increase in risk of acquiring a bloodstream, urinary tract, or respiratory infection, or being admitted to the ICU (p < 0.001), after statistically controlling for age and Injury Severity Score. When controlling for diabetes, gender, obesity, age, COPD, and Injury Severity Score, obese patients were 7.1 times (95% CI, 2.06-8.9) more likely to die in the hospital. CONCLUSIONS: Obesity is associated with a substantial increase in morbidity and mortality in the critically ill trauma patient. Future studies are warranted in both the prevention of infection and intensive care management of the obese trauma patient.     

Incidence and Impact of Risk Factors in Critically Ill Trauma Patients

There is a paucity of data describing the incidence of pre-existing diseases or risk factors and their effects in trauma patients. We conducted a prospective study to determine the incidence of such factors in critically ill trauma patients and to evaluate their impact on outcome. The study, performed over a 2-year period, examined the hospital course of all trauma patients admitted to the ICU. Multiple risk factors were evaluated and analyzed via multivariate regression analysis. Outcome was evaluated by infection rate, hospital length of stay, ventilator days, and mortality matched for age and Injury Severity Score (ISS). A total of 1172 patients (73% blunt injury) were enrolled over the study period. Of these, 873 (74.5%) were male. The mean age was 42.5 years with an ISS of 19.8. Tobacco use (24%) was the most common risk factor identified, followed by hypertension (HTN, 17%), coronary artery disease (9%), chronic obstructive pulmonary disease (COPD)/reactive airway disease (4%), non-insulin-dependent diabetes (NIDDM) (4%), insulin-dependent diabetes (IDDM) (3.2%), cancer (3%), liver disease (2%), and HIV/AIDS (1.4%). Of these risk factors, IDDM was found to be an independent risk factor for infection (0.004) and ventilator days (0.047), increasing age was found to be an independent risk factor for hospital length of stay (0.023) and mortality (<0.001), and HTN was found to be an independent risk factor for increased ventilator days (0.04). In addition, COPD/reactive airway disease was found to be an independent predictor of ventilator days, infection, and ICU days (P < 0.05). Thus, increased age, IDDM, COPD, and HTN are most predictive of outcome in critically ill trauma patients. With our aging population it is becoming increasingly important to identify pre-existing risk factors on admission in order to minimize their effects on outcome. Presented at the 2005 Annual Scientific Meeting of the South Eastern Surgical Congress, February 11–15, 2005,New Orleans, Louisiana.     

Admission hyperglycemia is predictive of outcome in critically ill trauma patients

OBJECTIVES: There is a paucity of data evaluating whether hyperglycemia at admission is associated with adverse outcome in trauma patients. Our objectives were to determine whether admission hyperglycemia was predictive of outcome in critically ill trauma patients. METHODS: Prospective data were collected daily on 1,003 consecutive trauma patients admitted to the intensive care unit over a 2-year period. Diabetics were excluded. Patients were stratified by admission serum glucose level (<200 mg/dL vs. > or =200 mg/dL) age, gender, Injury Severity Score, and other preexisting risk factors. Outcome was measured by incidence of infection, ventilator days, hospital length of stay and intensive care unit length of stay, and mortality. Multiple linear regression models were used to determine level of significance. RESULTS: Two hundred fifty-five of 1,003 (25%) patients were admitted with hyperglycemia over the study period. The majority (78%) of the admissions were caused by blunt injury. Male patients accounted for the majority of the study population (73%); however, female patients were more likely to be hyperglycemic at admission (p = 0.015). Patients with hyperglycemia had an overall greater infection rate and hospital length of stay. The hyperglycemic group had a 2.2-times greater risk of mortality when adjusted for age and Injury Severity Score. CONCLUSION: Hyperglycemia at admission is an independent predictor of outcome and infection in trauma patients. Future investigation on the effects of hyperglycemia are warranted.     

The impact of MRSA on vascular surgery.

OBJECTIVES: To investigate the prevalence of MRSA infection in patients treated in a major vascular unit and examine its consequences. DESIGN AND METHODS: A retrospective case-note review was performed. RESULTS: During the period 1993 to 2000, a total of 172 patients (4.4% of total) were positive for MRSA. Of these 97 were colonised and 75 were infected by MRSA. The proportion of wound or graft infections caused by MRSA has increased (4% in 1994 to 63% in 2000). Three patients developed native artery infection (one following aortic stent insertion and 2 following embolectomy). All patients with aortic graft infection died. All patients with infected prosthetic infrainguinal bypass ended up with an amputation. CONCLUSION: The prevalence of MRSA infection is increasing. Infection of aortic grafts appears to be uniformly fatal and lower limb graft infection is associated with high limb loss.     

A prospective randomised open label study to evaluate the potential of a new silver alginate/carboxymethylcellulose antimicrobial wound dressing to promote wound healing

The aim of this study was to observe both the clinical signs and symptoms of wounds at risk of infection, that is critically colonised (biofilm infected) and antimicrobial‐performance of an ionic silver alginate/carboxymethylcellulose (SACMC) dressing, in comparison with a non silver calcium alginate fibre (AF) dressing, on chronic venous leg and pressure ulcers. Thirty‐six patients with venous or pressure ulcers, considered clinically to be critically colonised (biofilm infected), were randomly chosen to receive either an SACMC dressing or a non silver calcium AF dressing. The efficacy of each wound dressing was evaluated over a 4‐week period. The primary study endpoints were prevention of infection and progression to wound healing. The SACMC group showed a statistically significant (P = 0·017) improvement to healing as indicated by a reduction in the surface area of the wound, over the 4‐week study period, compared with AF controls. In conclusion, the SACMC dressing showed a greater ability to prevent wounds progressing to infection when compared with the AF control dressing. In addition, the results of this study also showed an improvement in wound healing for SACMC when compared with a non silver dressing.     

Methicillin-resistant Staphylococcus aureus in an Irish orthopaedic centre: a five-year analysis

This prospective five-year study analyses the impact of methicillin-resistant Staphylococcus aureus (MRSA) on an Irish orthopaedic unit. We identified 318 cases of MRSA, representing 0.76% of all admissions (41,971). A total of 240 (76%) cases were colonised with MRSA, while 120 (37.7%) were infected. Patients were admitted from home (218; 68.6%), nursing homes (72; 22.6%) and other hospitals (28; 8.8%). A total of 115 cases (36.6%) were colonised or infected on admission. Many patients were both colonised and infected at some stage. The length of hospital stay was almost trebled because of the presence of MRSA infection. Encouragingly, overall infection rates have not risen significantly over the five years of the study despite increased prevalence of MRSA. However, the financial burden of MRSA is increasing, highlighting the need for progress in understanding how to control this resistant pathogen more effectively.     

Early glucose normalization does not improve outcome in the critically ill trauma population

Strict control of serum glucose in critically ill patients decreases morbidity and mortality. The objective of this study was to evaluate the effect of early normalization of glucose in our burn and trauma intensive care unit. From January 2002 to June 2005, 290 patients were admitted with serum glucose 150 mg/dL or greater and 319 patients with serum glucose less than 150 mg/dL. The patients with hyperglycemia were more severely injured and more often required operative intervention within the first 48 hours. The patients with hyperglycemia were at increased risk for infection and mortality. Of those 290 patients in the hyperglycemic cohort, 125 patients had early normalization of serum glucose, whereas 165 patients required more than 24 hours to normalize. The early normalization cohort was younger in mean age than the late group, but these 2 groups were similar in injury severity. Correspondingly, there was no difference in the rate of infection. Although hyperglycemia on admission appears to correlate with a worse outcome, early glucose normalization did not affect morbidity and mortality in our critically ill population.     

Persistent hyperglycemia is predictive of outcome in critically ill trauma patients

OBJECTIVES: Our objectives were to determine whether persistent hyperglycemia was predictive of outcome in critically ill trauma patients. METHODS: Prospective data were collected daily on 942 consecutive trauma patients admitted to the ICU over a 2-year period. Patients were stratified by serum glucose level from day 1 to day 7 (low = 0-139 mg/dL, medium = 140-219 mg/dL, and high >220 mg/dL) age, gender, and ISS. Patients were further stratified by pattern of glucose control (all low, all moderate, all high, improving, worsening, highly variable (HV). Outcome was measured by ventilator days, infection, hospital (HLOS) and ICU (ILOS) length of stay and mortality. Multiple linear regression models were used to determine level of significance. RESULTS: 71% were victims of blunt trauma. The majority (74%) were male with a mean ISS of 21.3 +/- 15. 41% of patients acquired an infection. Patients with medium, high, worsening, and highly variable hyperglycemia were found to have increased ILOS, HLOS, ventilator days, infection rate and mortality by univariate analysis (p < 0.01). When controlling for age, ISS, and glucose pattern, patients with high, worsening and HV hyperglycemia were most predictive of increased ventilator days, ILOS, HLOS, infection and mortality. (p < 0.01). CONCLUSION: Trauma patients with persistent hyperglycemia have a significantly greater degree of morbidity and mortality. A prospective randomized controlled study instituting aggressive hyperglycemic control is warranted.     

Effect of nosocomial bloodstream infection on the outcome of critically ill patients with acute renal failure treated with renal replacement therapy

Critically ill patients with acute renal failure (ARF) treated with renal replacement therapy (RRT) have a high mortality. The authors evaluated a cohort of 704 consecutive intensive care unit (ICU) patients with ARF treated with RRT to determine whether there was an increased incidence of nosocomial bloodstream infection and whether this resulted in a worse outcome. The incidence of nosocomial bloodstream infection was 8.8%, higher than that reported in other series of general ICU patients and also higher than the 3.5% incidence of bloodstream infection in non-ARF patients in the same unit (P < 0.001). There were more bloodstream infections caused by Gram-positive species compared with Gram-negative species or fungi. The distribution over the species was comparable to that reported by others for a general ICU population. The outcome was evaluated with matched cohort analysis. With this technique, patients with bloodstream infection (exposed) were closely matched with patients without bloodstream infection (non-exposed) in a 1:2 ratio. Matching was based on the APACHE II system and length of stay before bloodstream infection (exposure time). Length of stay and mortality were equal in exposed and non-exposed patients. There was also no difference in hospital costs. It can be concluded that critically ill patients with ARF treated with RRT were more susceptible to nosocomial bloodstream infection. Nevertheless, the outcome was not influenced by the presence of bloodstream infection. The high mortality observed in ARF patients could therefore not be attributed to the higher incidence of bloodstream infection.     

Evaluation of a clinical pathway for ventilator-associated pneumonia: changes in bacterial flora and the adequacy of empiric antibiotics over a three-year period

BACKGROUND: Evaluation of causative pathogens is vital for optimizing empiric antibiotic therapy of ventilator-associated pneumonia (VAP). Based on previous data (Ann Surg 1998;227:743-755), empiric antibiotics for our VAP clinical pathway were modified to target early and late occurring pathogens (ampicillin/sulbactam during the first week of hospitalization; cefepime plus vancomycin afterwards). The objectives of this study were to compare organisms causing VAP over a three-year period to previous data, and to determine the adequacy of the empiric antibiotic regimens. METHODS: A total of 299 critically ill trauma patients with VAP over a three-year period were studied retrospectively. The incidence of pathogens causing VAP in the study period were compared to a previously published study of a two-year period in our intensive care unit (ICU). Sensitivities of Pseudomonas aeruginosa and Acinetobacter baumannii were evaluated over the study period. The adequacy of empiric antibiotic therapy for each episode of VAP was determined. Therapy was considered to be adequate if one or more antibiotics had in vitro activity against the organism causing VAP. RESULTS: Statistically significant changes in pathogens included increased Staphylococcus aureus (incidence 17% vs. 11%, p = 0.024) and decreased Acinetobacter baumannii (11% vs. 22%, p < 0.001). Susceptibility patterns were statistically unchanged except for increased resistance of P. aeruginosa to extended-spectrum penicillins (p = 0.016). Empiric therapy was adequate in 76% of VAP episodes. CONCLUSIONS: The clinical pathway's empiric antibiotic regimen was associated with only modest changes in organisms causing VAP and provided a high rate of adequate empiric coverage.     

The gastrointestinal tract. The "undrained abscess" of multiple organ failure.

OBJECTIVE: This study determined the association between proximal gastrointestinal (GI) colonization and the development of intensive care unit (ICU)-acquired infection and multiple organ failure (MOF) in a population of critically ill surgical patients. SUMMARY BACKGROUND DATA: ICU-acquired infection in association with progressive organ system dysfunction is an important cause of morbidity and mortality in critical surgical illness. Oropharyngeal and gastric colonization with the characteristic infecting species is common, but its association with ICU morbidity is poorly defined. METHODS: A prospective cohort study of 41 surgical ICU patients was undertaken. Specimens of gastric and upper small bowel fluid were obtained for quantitative culture; the severity of organ dysfunction was quantitated by a numeric score. RESULTS: One or more episodes of ICU-acquired infection developed in 33 patients and involved at least one organism concomitantly cultured from the upper GI tract in all but 3. The most common organisms causing ICU-acquired infection--Candida, Streptococcus faecalis, Pseudomonas, and coagulase-negative Staphylococci--were also the most common species colonizing the proximal GI tract. Gut colonization correlated with the development of invasive infection within 1 week of culture for Pseudomonas (90% vs. 13% in noncolonized patients, p < 0.0001) or Staphylococcus epidermidis (80% vs. 6%, p < 0.0001); a weaker association was seen for colonization with Candida. Infections associated with GI colonization included pneumonia (16 patients), wound infection (12 patients), urinary tract infection (11 patients), recurrent (tertiary) peritonitis (11 patients), and bacteremia (10 patients). ICU mortality was greater for patients colonized with Pseudomonas (70% vs. 26%, p = 0.03); organ dysfunction was most marked in patients colonized with one or more of the following: Candida, Pseudomonas, or S. epidermidis. CONCLUSIONS: The upper GI tract is an important reservoir of the organisms causing ICU-acquired infection. Pathologic GI colonization is associated with the development of MOF in the critically ill surgical patient.     

Synchronous bacterial and fungal septicemia. A marker for the critically ill surgical patient

Mixed septicemia (synchronous fungal and bacterial septicemia) is an occasional, but often fatal occurrence in the critically ill patient. We reviewed 14 such cases at two hospitals. Twelve of 14 patients were in the surgical intensive care unit. Eleven patients had an average of 2.7 major surgical procedures (range 2 to 4); persistent post-operative peritoneal sepsis was common occurring in 9 patients. Bacteremia preceded mixed septicemia in 8 of 14 cases and gram negative enteric bacilli were the most common causes of bacteremia. Fungemia was due to Candida species in 13 of 14 patients and followed prolonged antibiotic therapy. The diagnosis of disseminated candidiasis was suspected during life in 13 patients and proven in six. Mixed septicemia is a marker for a distinct population of critically ill surgical patients with a high overall mortality (78% in this study). Culture of both a fungal and bacterial pathogen in a blood culture, especially if preceded by bacteremia, should alert the physician to strongly suspect disseminated fungal infection and to commence appropriate treatment. Mortality is likely to remain high unless the underlying disease states can be rapidly corrected and infection controlled.     

全身炎症反应综合征与多器官功能障碍综合征的临床研究

作者前瞻性调查了２３０例危重病患者,根据危重病患者全身性炎症反应综合征（ＳＩＲＳ）和多器官功能障碍综合征（ＭＯＤＳ）的症状,分析ＳＩＲＳ到ＭＯＤＳ的渐进发展过程,探讨治疗策略。结果显示：患者转入加强医疗病房（ＩＣＵ）时,ＳＩＲＳ患病率７１．３％,病死率１８．９％。２３０例患者中,６５例发生ＭＯＤＳ（２８．３％）,死亡３３例（５０．８％）。非感染性ＳＩＲＳ、全身性感染及感染性休克患者的ＭＯＤＳ患病率依次为２２．８％,６１．１％和８５．７％,而病死率依次为１１．４％,３０．６％和５０．０％。作者认为,早期诊断ＳＩＲＳ,并积极调控机体炎症反应,可能是改善危重患者预后的关键。     

Outcome of intensive care in the elderly

The long-term survival of elderly patients following critical illness in the United Kingdom has not previously been studied. The demographic (age, sex, diagnosis, severity of illness) and treatment details (admission type, length of treatment, prior surgery) of all critically ill patients aged over 70 years were recorded. The 1-year survival of such patients was measured and compared with that of a matched normal population. Of 474 patients aged over 70 years, 88 patients died on the intensive care unit (19% mortality) and a further 133 died within 1 year (total mortality 47%). The 1-year survival of patients aged <85 years was 56% which was significantly better than that of patients over 85 years (27%). The survival of all critically ill elderly patients was significantly poorer than that of a matched normal population (1-year survival 93%). Logistic regression revealed that age, diagnosis and severity of illness are independent predictors of 1-year survival.