Temporal Scanner Thermometry: A New Method of Core Temperature Estimation in ICU Patients

Background and Aims: Temperature measurement is a routine task of patient care, with considerable clinical impact, especially in the ICU. This study was conducted to evaluate the accuracy and variability of the Temporal Artery Thermometer (TAT) in ICU-patients. Therefore, a convenience sample of 57 adult patients, with indwelling pulmonary artery catheters (PAC) in a 40-bed intensive care unit in a university teaching hospital was used. Methods: The study design was a prospective, descriptive comparative analysis. Body temperature was thereby measured simultaneously with the TAT and the Axillary Thermometer (AT), and was compared with the temperature recording of the PAC. The use of vasoactive medication was recorded. Results and conclusions: Mean temperature of all measurements was: PAC: 37.1°C (SD: 0.87), TAT: 37.0°C (SD: 0.68) and axillary thermometer: 36.6°C (SD: 0.94). The measurements of the TAT and the PAC were not significantly different (mean difference: 0.14°C; SD: 0.51; p= 0.33); whereas the measurements of the PAC and the AT differed significantly (mean difference: 0.46°C; SD: 0.39; p< 0.001). Mean difference in PAC versus TAT analyses, between patients with vasopressor therapy (0.12°C; SD: 0.55), and without vasopressor therapy (0.19°C; SD: 0.48) was not statistically significant (p= 0.47). Conclusion: We can conclude that the temporal scanner has a relatively good reliability with an acceptable accuracy and variability in patients with normothermia. The results are comparable to those of the AT, but they do not seem to be sufficient to prove any substantial benefit compared to rectal, oral or bladder thermometry.

APPROPRIATE AND TIMELY EMPIRICAL ANTIMICROBIAL TREATMENT OF ICU INFECTIONS - A ROLE FOR CARBAPENEMS

Treatment of serious nosocomial infections in the intensive care unit requires swift, effective, well-tolerated and appropriate therapy from the outset. The consequences of inappropriate treatment, i.e. the use of antibiotics that are ineffective against the causative pathogen(s) or delayed therapy, are numerous and impact negatively upon both the patient and the ever-dwindling healthcare resources in many hospitals. Although antibiotics have revolutionised the treatment of infections, their inappropriate and untimely use within the intensive care setting has led to the emergence and spread of antibiotic-resistant bacteria worldwide. Consequently, to ensure successful patient outcomes (reduce morbidity and mortality), it is important that any antibiotic treatment employed is right first time. Treatment of serious infections in the intensive care unit requires an empirical stratagem providing broad-spectrum coverage to a wide range of suspected or difficult-to-treat pathogens such as Pseudomonas aeruginosa. However, to prevent the errors of the past, this needs to be tailored as soon as the pathogen has been identified and resistance patterns are known. The carbapenems are potent parenteral antibiotics, with an ultra-broad spectrum of activity that encompasses multi-drug resistant and difficult-to-treat Gram-negative bacteria. Clinical trial data supports the clinical effectiveness of these agents in patients with difficult to treat pathogens.

Antimicrobial therapy for intra-abdominal infections: guidelines from the Infectious Disease Advisory Board (IDAB)

Intra-abdominal infection is a common cause of severe sepsis in a hospital setting and remains associated with a significant morbidity, mortality and resource use. Early adequate surgery or drainage remain the cornerstones of intra-abdominal infection management and impact on patients outcome. Concomitant early and adequate empiric antimicrobial therapy further influences patients morbidity and mortality. Multiple empirical regimens have been proposed in this setting, but rarely supported by well designed, randomized-controlled studies. The current manuscript summarizes the recommendations of the Infection Disease Advisory Board on the management of intra-abdominal infections. Empiric antimicrobial therapy for the most common causes of abdominal infections is proposed. In addition, particular attention has been paid on antibiotic treatment duration.

Ventilator-associated pneumonia in a tertiary care ICU: analysis of risk factors for acquisition and mortality

OBJECTIVE

To investigate the incidence, risk factors and mortality of ventilator-associated pneumonia (VAP) in intensive care unit (ICU) patients.

DESIGN

Prospective, observational, population-based study.

SETTING

The medical (14-bed) and surgical ICU (26-bed) of the Ghent University Hospital.

METHODS

All 1295 patients admitted to the ICU during 4 three-month periods between 1996 and 1998 were included. A set of demographic and clinical variables were collected at the day of admission and during the ICU course.

RESULTS

The incidence of VAP among ICU patients ventilated at least 48 hours was 23.1%. The mean time to the development of VAP was 9.6 days with a median of 6 days. In the population of patients ventilated for at least 48 hours, a comparison was made between patients with (n = 89) and without VAP (n = 296). Patients with VAP had a significant longer ICU stay, with a longer ventilation dependency. Logistic regression analysis identified admission diagnosis other than trauma (OR: 0.51, 95% CI: 0.29-0.89; p = 0.02) and the length of ICU stay (OR: 1.05, 95% CI: 1.03-1.07; p < 0.001) to be independently associated with the acquisiton of VAP. In comparison with the total study population, patients with VAP had a higher ICU mortality (20.2% vs. 12.0%; p = 0.04), but not in the cohort group of patients at risk for VAP (ventilated > 48 hours)(20.2% vs. 31.3%; p = 0.03). The factors independently associated with death were higher SAPS II scores (OR 1.02, 95% CI: 1.003-1.032; p = 0.02), an admission diagnosis other than trauma (OR 0.36, 95% CI: 0.17-0.75; p = 0.006) and length of ICU stay (OR 0.97, 95% CI: 0.946-0.995; p = 0.02). This model did not recognize VAP as an independent predictor of death (OR 0.79, 95% CI: 0.41-1.53; p = 0.492).

CONCLUSIONS

The incidence of VAP in our ICU is 23.1%. Length of ICU stay and an admission diagnosis other than trauma are major risk factors for the development of this nosocomial infection. VAP is associated with a high fatality rate. However, after adjustment for disease severity and length of ICU stay, VAP was not identified as an independent predictor of death.

Invasive aspergillosis in critically ill patients: analysis of risk factors for acquisition and mortality

OBJECTIVE

To investigate outcome in patients who develop invasive aspergillosis in the ICU, and to evaluate whether specific risk factors for the acquisition of invasive aspergillosis are associated with mortality.

DESIGN

Retrospective cohort study (07/1997-12/1999) with screening of 8988 admissions.

SETTING

54-bed ICU of the 1060-bed Ghent University Hospital.

PATIENTS

38 ICU patients with invasive aspergillosis. Invasive aspergillosis was defined as proven by positive histology and tissue culture and as probable by a combination of clinical suspicion as well as microbiological and radiological data. Seventeen patients had risk factors (neutropenia, haematological malignancy, immunosuppressive therapy). In the other 21 apparently immunocompetent patients, invasive aspergillosis was a complication following ARDS, COPD, pneumonia, acute liver failure, burns, severe bacterial infection and malnutrition.

MEASUREMENTS

Population characteristics and outcome were compared for patients with and without risk factors for the acquisition of invasive aspergillosis.

RESULTS

Patients with risk factors had higher APACHE II scores. No difference was found between patients with and without risk factors in in-hospital mortality (82% vs. 71%; p=0.431). In patients with specific risk factors, the observed mortality was not different from the mortality as expected on basis of the APACHE II (p=0.940). In patients without risk factors the observed mortality exceeded the expected mortality (p<0.001).

CONCLUSION

The incidence of invasive aspergillosis in this series is 4/1000 admissions. No difference in mortality was found between patients with and without risk factors for the acquisition of invasive aspergillosis. Yet, the prognosis of the patients without risk factors seems to alter more seriously by the development of this infection.

The effect of tube thoracostomy on oxygenation in ICU patients

Previous research found that in noncritically ill patients, thoracocentesis has an unpredictable effect on oxygenation, possibly due to re-expansion pulmonary edema and systemic hypotension. The authors performed a retrospective analysis to study the effect of tube thoracostomy on oxygenation in ICU patients, and the complications associated with it. The authors reviewed the charts of 58 ICU patients in whom 74 procedures were performed. Demographic data, APACHE II score, and indication for thoracocentesis were retrieved from the patient's file. The P(a)O(2)/FiO(2) ratio was calculated before, 12, 24, and 48 hours after tube thoracostomy. P(a)O(2)/FiO(2) ratios at the mentioned time intervals were compared using 1-way analysis of variances (ANOVA) with repeated measures. Logistic regression analysis was used to identify factors associated with a good response to treatment. Age of the patients was 53 +/- 19.0 years (range, 17-88), APACHE II score was 21 +/- 8.3 (range, 6-38), and median length of stay was 13.5 days (interquartile range, 7-25). The volume drained during the first 24 hours was 1077 +/- 667 ml. P(a)O(2)/FiO(2) ratio was 185 +/- 79.3 before chest drainage, 197 +/- 79.1 at 12 hours, 217 +/- 88.9 at 24 hours, and 233 +/- 99.8 at 48 hours. In only 54% of the procedures, a response to therapy was present. Multivariate analysis identified a P(a)O(2)/FiO(2) below 180 to be independently associated with improvement in oxygenation. At 24 and 48 hours, the P(a)O(2)/FiO(2) ratio was significantly higher than before drainage (P <.001). There were 13 complications in 11 procedures (14.9%). The authors' results suggest that tube thoracostomy can be used as an adjunct in the treatment of selected patients with hypoxemic respiratory failure in the ICU. A low P(a)O(2)/FiO(2) seems to be a good predictor of response to therapy. However, the complication rate is considerable, especially in patients with a prolonged ICU stay.

Bloodstream infections after surgery for severe acute pancreatitis

OBJECTIVE

To analyze the incidence and outcome of bloodstream infections (BSIs) in patients operated on for severe acute pancreatitis to identify the source and associated risk factors.

METHODS

We retrospectively (1995-2001) analyzed 45 patients treated surgically for severe acute pancreatitis. We recorded demographic characteristics, data on surgical and medical treatment and disease severity, the occurrence of BSIs, microbiological data concerning the BSIs and other infectious processes, the incidence of organ failure, and data on surgical and infectious complications.

RESULTS

Fifteen episodes of BSI were found in 7 of 45 patients (15%), with 18 organisms involved. In all but 1 episode, the source of the BSI was pancreatic necrosis. Most of the organisms were gram positive (11); the others were gram negative (6) or fungi (1). Mortality was statistically not different in patients with a BSI (57% vs. 35%). Multivariate analysis demonstrated that only the length of intensive care unit (ICU) stay was associated with the occurrence of BSIs (OR, 1.05; 95% CI, 1.02-1.09; P < 0.01).

CONCLUSION

A BSI is not a rare finding after surgery for severe acute pancreatitis, especially in patients with a prolonged ICU stay. The source is the infected necrosis in most of BSI episodes.

Invasive aspergillosis in critically ill patients: attributable mortality and excesses in length of ICU stay and ventilator dependence

Invasive aspergillosis is a rare disease in intensive care unit (ICU) patients and carries a poor prognosis. The aim of the present study was to determine the attributable mortality due to invasive aspergillosis in critically ill patients. In a retrospective, matched cohort study (July 1997-December 1999), 37 ICU patients with invasive aspergillosis were identified together with 74 control patients. Matching of control (1:2) patients was based on the acute physiology and chronic health evaluation (APACHE) II classification: an equal APACHE II score (+/-1 point) and diagnostic category. This matching procedure results in an equal expected in-hospital mortality for cases and controls. Additionally, control patients were required to have an ICU stay equivalent to or longer than the case before the first culture positive for Aspergillus spp. Patients with invasive aspergillosis were more likely to experience acute renal failure (43.2% versus 20.5%; P = 0.020). They also had a longer ICU stay (median: 13 days versus seven days; P < 0.001) as well as a more extended period of mechanical ventilator dependency (median: 13 days versus four days; P < 0.001). Hospital mortalities for cases and controls were 75.7% versus 56.8%, respectively (P=0.051). The attributable mortality was 18.9% (95% CI: 1.1-36.7). A multivariate survival analysis showed invasive aspergillosis [hazard ratio (HR): 1.9, 95% CI: 1.2-3.0; P = 0.004] and acute respiratory failure (HR: 6.5, 95%: 1.4-29.3; P < 0.016) to be independently associated with in-hospital mortality. In conclusion, it was found that invasive aspergillosis in ICU patients carries a significant attributable mortality of 18.9%. In a multivariate analysis, adjusting for other co-morbidity factors, invasive aspergillosis was recognized as an independent predictor of mortality.

Infectious complications of acute pancreatitis

Disease severity in patients with acute pancreatitis varies from mild disease with minimal morbidity, to severe disease in which a whole spectrum of local and systemic complications may occur. Infectious complications frequently arise, and especially infection of pancreatic necrosis is an important risk factor for mortality. Several strategies have been devised to reduce this risk, and the use of prophylactic therapy, e.g. selective digestive decontamination, can be considered in patients with documented necrosis fo the pancreas. Pancreatic abscesses and infected pseudocysts arise later in the course of disease, and should be considered as separate entities, due to differences in therapy and outcome of these patients. When infection occurs, source control using either surgical or percutaneous drainage techniques, is essential to avoid systemic complications.

Adrenal insufficiency in severe acute pancreatitis

Relative adrenal insufficiency is common in patients with severe sepsis and septic shock. We describe three patients with severe acute pancreatitis who developed signs suggestive of adrenal insufficiency during the early phase of the disease. Clinical features and possible causes of adrenal insufficiency are discussed.

Fungal infections in patients with severe acute pancreatitis and the use of prophylactic therapy

Data from an 8-year period for 46 patients with severe acute pancreatitis and infected pancreatic necrosis were analyzed to determine the incidence of fungal infection, to identify risk factors for the development of fungal infection, and to assess the use of early fluconazole treatment. Intraabdominal fungal infection was found in 17 (37%) of 46 patients. Candida albicans was isolated most frequently (15 patients); Candida tropicalis and Candida krusei were found in 1 patient each. Characteristics of patients with fungal infection were not different from patients without fungal infection. The difference in mortality was not statistically significant between patients with fungal infection and patients without fungal infection. Early antifungal therapy (prophylactic or preemptive antifungal therapy) was administered to 18 patients, and only 3 of them developed fungal infection. In this cohort of critically ill patients, no risk factors for fungal infection could be demonstrated, and mortality among patients who received early antifungal therapy was not different. Early treatment with fluconazole seems to prevent fungal infection in these high-risk patients.

Reappraisal of attributable mortality in critically ill patients with nosocomial bacteraemia involving Pseudomonas aeruginosa

In a retrospective study, population characteristics and outcome were investigated in intensive care unit (ICU) patients with hospital-acquired Pseudomonas aeruginosa bacteraemia admitted over a seven-year period (January 1992 through December 1998). A matched cohort study was performed in which all ICU patients with P. aeruginosa bacteraemia were defined as cases (N=53). Matching (1:2 ratio) of the controls (N=106) was based on the APACHE II classification: an equal APACHE II score (+/-1 point) and an equal diagnostic category. Patients with P. aeruginosa bacteraemia had a higher incidence of acute respiratory failure, haemodynamic instability, a longer ICU stay and length of ventilator dependence (P<0.05). In-hospital mortalities for cases and controls were 62.3 vs. 47.2% respectively (P=0.073). Thus, the attributable mortality was 15.1% (95% confidence intervals: -1.0-31.2). In a multivariate survival analysis the APACHE II score was the only variable independently associated with mortality. In conclusion, P. aeruginosa bacteraemia is associated with a clinically relevant attributable mortality (15%). However, we could not find statistical evidence of P. aeruginosa being an independent predictor of mortality.

Evaluation of human albumin use in a university hospital in Belgium

In 1996-1997, a drug use evaluation (DUE) of human albumin was conducted in the Ghent University Hospital (Belgium) to determine the pattern and appropriateness of the albumin use. The DUE was followed by permanent review of the albumin consumption. This paper describes how the DUE was carried out and how the albumin use in our hospital changed over time.

METHOD

The study was based on criteria for indications and end of treatment, accepted by consensus of the physicians prescribing albumin. Albumin treatment episodes were classified as appropriate or inappropriate according to these criteria.

RESULTS

For 115 treatment episodes in 90 patients, the researchers found 21 (18.3%) deviations from the developed criteria. After analysis, half out of them were considered as minor. Most deviations involved starting treatment too early (n = 17). Follow-up results indicated that the overall consumption of albumin dropped by 50.1% from 1994 to 1999, while the consumption of colloid solutions during the same period remained stable.

CONCLUSION

A good compliance with internally developed criteria for indications and end of treatment with human albumin was observed. Discussion with the clinicians involved led to the development of stricter criteria and a continuous decrease in albumin consumption.

Outcome in critically ill patients with candidal fungaemia: Candida albicans vs. Candida glabrata

In a retrospective study (1 January 1992-12 December 1998), we investigated population characteristics and outcome in critically ill patients with fungaemia involving C. albicans (n=41) and C. glabrata (n=15). Patients with C. glabrata fungaemia were significantly older compared with patients in the C. albicans group (P=0.024). There were no other differences in population characteristics or severity of illness. Logistic regression analysis showed age (P=0.021), the presence of a polymicrobial blood stream infection (P=0.039), and renal failure (P=0.044) to be independent predictors of mortality. There was no significant difference in in-hospital mortality between the C. glabrata and C. albicans groups (60.0% vs. 41.5%; P=0.24). Since age was an independent predictor of mortality, the trend towards a higher mortality in patients with C. glabrata can be explained by this population being significantly older. In conclusion, we found no difference in mortality between patients with fungaemia involving C. albicans and C. glabrata.

Course of neuropsychological recovery from moderate-to-severe head injury: a 2-year follow-up

Neuropsychological outcome and recovery of a group of 91 patients with moderate-to-severe head injuries were prospectively investigated over a 2 year period, with evaluations at acute hospital discharge at 6 months and 2 years post-injury. A group of 39 trauma patients with injuries to parts of the body other than the head were used as controls. The head injured group performed significantly worse than the control group at baseline, 6 months and 2 years post-injury. Significant improvement was found during the first 6 months, but also between 6 months and 2 years post-injury. Trauma controls also performed significantly better at 6 months post-injury compared to baseline. Differential practice effects between groups cause difficulties in determining recovery. Within the head injured group, three distinct recovery groups were identified varying as a function of coma-length and coma-duration. The first group is comparable with the trauma controls. The other two groups demonstrate significant neuropsychological impairments at baseline, with one group showing a marked improvement over the 2 year period, and the other group showing only small improvement over this time period.

Prevalence and risk factors for colonisation with gram-negative bacteria in an intensive care unit

OBJECTIVE

To investigate prevalence and determine risk factors for colonisation with Gram-negative bacteria in ICU patients.

DESIGN

Prospective, surveillance study.

SETTING

26-bed surgical and paediatric ICU.

PATIENTS

159 patients--whereof 22 infants--admitted to the surgical/paediatric ICU over a two-month period.

INTERVENTION

In all patients routine microbiological monitoring was performed by thrice weekly oral swabs, urine sampling and, additionally, tracheal aspirates in patients on mechanical ventilation (MV) and by anal swabs once weekly.

RESULTS

Population characteristics: Mean age of the adult population was 51.1 +/- 17.6 year. Mean age of the paediatric population was 6.3 +/- 5.3 year. The mean APACHE II-score was 18 +/- 9.1. The mean PRISM-score was 9.7 +/- 5.4. The mean ICU stay was 7.5 +/- 11.4 days. 43.4 percent of patients received mechanical ventilation (MV). The mean number of mechanical ventilation days was 11.1 +/- 14.7 days. 32.1% of patients experienced colonisation with Gram-negative bacteria. Prevalence of colonisation increased with length of ICU stay. The probability of colonisation was 24% after an ICU stay of 3 days (= median ICU stay). Time to colonisation was not different between the controlled sites (p > 0.05). 47% of colonizations were due to multiresistant strains. Higher APACHE II-scores and MV were associated with a higher prevalence of colonisation (p < 0.01). The ICU mortality was 8% among adult and 4% among paediatric patients.

CONCLUSION

Patients with high APACHE II-scores, on mechanical ventilation and with an ICU stay of more than 3 days are most at risk for colonisation with Gram-negative bacteria. These patients should be cared with the optimal precautions in the prevention of colonisation and infection.

Early predictors of mortality and morbidity after severe closed head injury

Mortality and morbidity of 158 patients with severe head injury were studied in relation to age, and early (24-h) clinical and computed tomography data. For comparison of outcome data in survivors, a group of 32 patients with traumatic injuries to parts of the body other than the head was used as controls. Within the head-injured group, the mortality rate was 51%. Logistic regression analyses combined 13 out of 16 predictors into a model with an accuracy of 93%, a sensitivity of 90%, and a specificity of 95%. These include age, Glasgow Coma Scale (GCS) score, pupillary reactivity, blood pressure, intracranial pressure, blood glucose, platelet count, body temperature, cerebral lactate, and subdural, intracranial, subarachnoid, and ventricular hemorrhage. At 6 months postinjury, head-injury survivors and trauma controls were evaluated with the Glasgow Outcome Scale (GOS), a neuropsychological test battery and the Sickness Impact Profile (SIP). Head-injury survivors had a higher proportion of disabilities and neuropsychological dysfunctions than trauma controls. They also report more quality of life-related functional limitations on the SIP scales for mobility, intellectual behavior, communication, home management, eating, and work. Linear regression analysis resulted in age being the only important predictor of outcome on the GOS, the GCS score being the best predictor of neuropsychological functioning, and pupillary reactivity being the most predictive for self-reported quality of life as measured by SIP. Those factors important for predicting mortality (clinical variables such as ICP or blood glucose level, and CT observations) failed to show any significant relationship with morbidity.

Indigenous malaria in a suburb of Ghent, Belgium

We report here details of a patient with Plasmodium falciparum malaria which was acquired in the vicinity of Ghent (Evergem) in July 1997. Indigenous malaria disappeared from Belgium in 1938. Due to an increase in international travel, the influx of migrant labor and the changing environmental conditions, there has been an upsurge of imported malaria. Airport- and port-malaria is acquired through the bite of a tropical anophelline mosquito by people whose geographical history excludes exposure to this vector in its natural habitat. As far as we know, only two cases of port-malaria have been reported: in Marseille. We describe here another possible case of port-malaria due to infection with P. falciparum in a 42-year-old woman with an underlying non-Hodgkin lymphoma.

Functional, life-threatening disorders and splenectomy following liver transplantation

Splenectomy (SPL) in cirrhotic patients undergoing liver transplantation (LTx) may resolve specific problems related to the procedure itself, in case of functional and life-threatening clinical situations often occurring as a result of liver cirrhosis and portal hypertension.

METHOD

A single-center experience of ten splenectomies in a series of 180 consecutive adult liver transplant patients over a period of 6 yr is reported. The mean patient age was 46.8 +/- 9.5 yr (range 25 57 yr). Indications for SPL were post-operative massive ascitic fluid loss (n = 3), severe thrombocytopenia (n = 3), acute intra-abdominal hemorrhage (n = 2), infarction of the spleen (n = 1), and multiple splenic artery aneurysms (n = 1).

RESULTS

Extreme ascites production due to functional graft congestion disappeared post-SPL, with an improvement of the hepatic and renal functions. SPL was also effective in cases of thrombocytopenia persistence post-LTx, leading to an increase in the platelet count after about 1 wk. Bleeding episodes related to left-sided portal hypertension or trauma were also resolved. The rejection rate during hospitalization was 0%, and no other episodes were recorded in the course of the long-term follow-up. However, sepsis with a fatal outcome occurred in 4 patients, i.e. between 2 and 3 wk post-SPL in three cases and 1 yr after the procedure as a result of pneumococcal infection in the last case. Fatal traumatic cranial injury occurred 3 yr post-LTx in another case. Five patients (50%) are still alive and asymptomatic after a median follow-up period of 36 months.

CONCLUSION

The lowering of the portal flow appears to resolve unexplained post-operative ascitic fluid loss as a result of functional graft congestion following LTx. However, because of the enhanced risk of SPL-related sepsis, a partial splenic embolization (PSE) or a spleno-renal shunt could be used as an alternative procedure because it allows us to preserve the immunological function of the spleen. SPL is indicated in case of post-transplant bleeding due to left-sided portal hypertension and trauma, spleen infarction, and to enable prevention of hemorrhage in liver transplant patients with multiple splenic artery aneurysms. Severe and persistent thrombocytopenia could be treated with PSE. Because the occurrence of fatal sepsis post-SPL is a major complication in LTx, functional disorders, such as ascites and thrombocytopenia, should be treated with a more conservative approach.

Contractility in humans after coronary artery surgery

BACKGROUND

Propofol's unique pharmacokinetic profile offers advantages for titration and rapid emergence in patients after coronary artery bypass graft (CABG) surgery, but concern for negative inotropic properties potentially limits its use in these patients. The current study analyzed the effect of various propofol plasma concentrations on left ventricular (LV) contractility by means of a single-beat contractile index based on LV maximal power (PWR(max)).

METHODS

The study was conducted in 30 patients after CABG surgery. Immediately after admission to the intensive care unit (ICU), four different plasma concentrations of propofol 0.65, 1.30, 1.95, and 2.60 microg/ml were established. At each concentration level, the cardiac and vascular effects of propofol were studied by combining echocardiographic data with invasively derived aortic root pressure. Preload was characterized by LV end-diastolic dimensions. Afterload was indicated in terms of indexed systemic vascular resistance (SVRI), LV end-systolic meridional wall stress (LV-ESWS), and arterial elastance (Ea). Quantification of effects on contractility was achieved by preload-adjusted PWRmax.

RESULTS

Myocardial contractility did not change during a fourfold increase in propofol plasma concentration. Preload-adjusted PWRmax amounted to 3.90+/-1.75 W x ml(-2) x 10(4), 3.98+/-1.69, 3.94+/-1.70, and 3.88+/-1.72, respectively (mean+/-SD). With respect to ventricular loading conditions, propofol caused a significant reduction in both pre- and afterload.

CONCLUSIONS

The current results strongly suggest that propofol lacks direct cardiac depressant effects. Nevertheless, meaningful vascular actions of propofol could be demonstrated. Significant decreases in ventricular loading conditions accounted for a marked decrease in arterial blood pressure and supported the concept that propofol in clinically relevant concentration is a vasodilator.

Intensive care for very elderly patients: outcome and risk factors for in-hospital mortality

OBJECTIVES

To evaluate outcome and risk factors, particularly the Acute Physiology and Chronic Health Evaluation (APACHE) II scoring system, for in-hospital mortality in very elderly patients after admission to an intensive care unit (ICU).

METHODS

Retrospective chart review of patients > or =85 years admitted to the ICU. We recorded age, sex, previous medical history, primary diagnosis, date of admission and discharge or death, APACHE II score on admission, use of mechanical ventilation and inotropics, and complications during ICU admission.

RESULTS

104 patients > or =85 years (1.3% of all ICU admissions) were studied. The ICU and in-hospital mortality rates for these patients were 22 and 36% respectively. Factors correlated with a greater in-hospital mortality were: an admission diagnosis of acute respiratory failure (chi2; P = 0.007), the use of mechanical ventilation (chi2; P = 0.00005) and inotropes (chi2; P = 0.00001), complications during ICU admission (chi2; P = 0.004), in particular acute renal failure (chi2; P = 0.005), and an APACHE II score > or =25 (chi2; P = 0.001). The APACHE II scoring system and the use of inotropes were independently correlated with mortality.

CONCLUSION

ICU and in-hospital mortality are higher in very elderly patients, particularly in those with an APACHE II score > or =25. The most important predictors of mortality are the use of inotropes and the severity of the acute illness.

Two cases of disseminated mucormycosis in patients with hematological malignancies and literature review

Two cases of disseminated mucormycosis in patients with underlying hematological disease are described. Both patients presented with fever and pulmonary infiltrates which did not respond to empirical treatment with broad-spectrum antibiotics and antifungal agents, and in both patients there was rapid progression with a fatal outcome. All cultures were negative and the diagnosis was made postmortem. A review of the literature revealed only three recent reports of successful treatment of disseminated mucormycosis. Survival correlated with control of the underlying disease and early diagnosis based on histological examination of biopsy specimens from suspected lesions. Therapy consisted of surgical debridement and amphotericin B. Standard therapeutic schedules need to be defined for this infection.

Use of continuous bispectral EEG monitoring to assess depth of sedation in ICU patients

Monitoring the depth of sedation in patients under intensive care is difficult. Clinical assessment by the different scoring systems produces insufficient information, especially once deeply sedated patients become unresponsive to any external stimulation. Recently, the bispectral index (BIS), the result of computerized bispectral electroencephalographic monitoring, was found to be the best predictor of depth of anaesthesia during surgical intervention. This report concerns BIS monitoring in 18 randomly selected, deeply sedated, surgical patients in the intensive care unit, who were unresponsive to standard clinical stimulation (Ramsay sedation score). A wide range of BIS was observed, with 15 of the patients having a BIS below 60, indicating a state of deep sedation (or possibly over-sedation). Therefore, further studies using BIS monitoring in patients under intensive care are needed to determine if this method can guide sedation and prevent oversedation in this context and, most importantly, to analyse its final cost-benefit ratio.

Pressure measurement evaluation and accuracy validation: the Gabarith test

OBJECTIVE

The dynamic distortion introduced by manometric systems has been known for many years, with several methods developed to describe and quantify the degree of distortion. We developed the Gabarith as a technique to describe more accurately, and yet more simply, the dynamic accuracy of the chain of monitoring.

SETTING

A pressure monitoring system transforms some input signal, i.e. the actual pressure waveform present in the artery, into some other shape of waveform, i.e. the waveform displayed on the patient monitor. This transformation is characterized by the transfer function of the total system. A complete technique to define the transfer function is to measure the response directly at many different frequencies and combine them to produce the dynamic response plot.

METHOD

We described the dynamic response of a monitoring chain and we simplified the communication of this dynamic response to users by developing the Gabarith, as a tolerance envelope based on the frequency content of typical pressure waveforms. If a given monitoring chain's dynamic response (including a catheter, a pressure kit and a monitor) can be shown to fall within that tolerance envelope, the chain will provide adequate dynamic accuracy.

CONCLUSION

"Gabarith tested" means that a pressure kit, in combination with a catheter and a monitor, has had its frequency response function measured and that the function falls within a tolerance band for dynamic accuracy. Passing a Gabarith means that a given level of accuracy will be reached when using the sets which have passed the corresponding test.

Use of the SOFA score to assess the incidence of organ dysfunction/failure in intensive care units: results of a multicenter, prospective study. Working group on "sepsis-related problems" of the European Society of Intensive Care Medicine

OBJECTIVE

To evaluate the use of the Sequential Organ Failure Assessment (SOFA) score in assessing the incidence and severity of organ dysfunction in critically ill patients.

DESIGN

Prospective, multicenter study.

SETTING

Forty intensive care units (ICUs) in 16 countries.

PATIENTS

Patients admitted to the ICU in May 1995 (n = 1,449), excluding patients who underwent uncomplicated elective surgery with an ICU length of stay <48 hrs.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The main outcome measures included incidence of dysfunction/failure of different organs and the relationship of this dysfunction with outcome. In this cohort of patients, the median length of ICU stay was 5 days, and the ICU mortality rate was 22%. Multiple organ dysfunction and high SOFA scores for any individual organ were associated with increased mortality. The presence of infection on admission (28.7% of patients) was associated with higher SOFA scores for each organ. The evaluation of a subgroup of 544 patients who stayed in the ICU for at least 1 wk showed that survivors and nonsurvivors followed a different course. This subgroup had greater respiratory, cardiovascular, and neurologic scores than the other patients. In this subgroup, the total SOFA score increased in 44% of the nonsurvivors but in only 20% of the survivors (p < .001). Conversely, the total SOFA score decreased in 33% of the survivors compared with 21% of the nonsurvivors (p < .001).

CONCLUSIONS

The SOFA score is a simple, but effective method to describe organ dysfunction/failure in critically ill patients. Regular, repeated scoring enables patient condition and disease development to be monitored and better understood. The SOFA score may enable comparison between patients that would benefit clinical trials.

Subjective complaints versus neuropsychological test performance after moderate to severe head injury

Neuropsychological test performance and subjective complaints of 85 patients with moderate to severe head injury were investigated at 6 months postinjury. The neuropsychological test battery included 10 measures of attention, memory, mental flexibility, reaction time, visuoconstruction and verbal fluency. Subjective complaints were assessed using a self-report questionnaire subdivided into four subscales (somatic, cognitive, emotional and behavioural). Ratings were obtained for the pre-injury and current status. Thirty-three trauma patients with injuries to other parts of the body than the head were used as controls. For the head injured, relatives also completed the questionnaire. Head injured patients performed significantly below trauma control patients on nearly all test measures. Head injured patients and their relatives reported a significant increase in subjective complaints since the injury on all four subscales, with no differences between patients' and relatives' reports. These changes were also reported by the trauma controls, but they report fewer changes in somatic and cognitive functioning. Exploratory canonical correlation analyses revealed no correlations between any of the four scales of the questionnaire and the test measures, nor for the head injured, the trauma controls, or the relatives, indicating no relevant relationship between subjective complaints and neuropsychological test performance.

Jugular bulb oximetry: review on a cerebral monitoring technique

Jugular bulb oximetry is the first available continuous monitoring method estimating the adequacy of cerebral perfusion. Despite its major technical as well as methodological shortcomings the information on the oxygen supply to demand balance of the brain seems most valuable. Especially the deleterious consequences of systemic variations (mainly concerning arterial blood pressure and CO2-tension) on the diseased brain are revealed by jugular bulb saturation values. The prevention and/or the early detection of these systemic secondary insults could have important implications as to final neurological outcome. Jugular bulb oximetry could also guide specific intracranial antihypertensive treatment, as it may reveal the pathophysiological mechanisms behind intracranial hypertension with regard to the status of cerebral perfusion (cerebral hyperemia or cerebral hypoperfusion). These insights might increase the efficacy of all treatments available for intracranial hypertension.

Cerebral perfusion pressure and intracranial pressure in relation to neuropsychological outcome

OBJECTIVE

The study attempted to examine the relationship between neuropsychological functioning and reduced cerebral perfusion pressure (CPP), raised intracranial pressure (ICP), and reduced mean arterial pressure (MAP), monitored during intensive care treatment.

DESIGN

This prospective follow-up study included consecutive patients and evaluated outcome at 6 months postinjury by the administration of a neuropsychological test battery.

SETTING

The study was conducted at the University Hospital of Gent, Belgium.

PATIENTS AND PARTICIPANTS

Over a 30-month period, 43 patients were included. Inclusion criteria were the following: hospital admission following closed head injury. ICP monitoring, no medical history of central nervous system disease or mental retardation, survival for at least 6 months, and informed consent for participation.

INTERVENTIONS

All patients received the hospital's standard treatment for head injury, which remained unchanged during the study period.

MEASUREMENTS AND RESULTS

Reduced CPP was analyzed using the number of observed values below 70 mmhg, raised ICP using the number of values above 20 mmHg, and MAP using the number of values below 80 mmHg. The neuropsychological test battery included 11 measures of attention, information processing, motor reaction time, memory, learning, visuoconstruction, verbal fluency, and mental flexibility. No linear relationships were found between overall neuropsychological impairment and episodes of reduced CPP, raised ICP, or reduced MAP.

CONCLUSIONS

Although reduced CPP and raised ICP are frequent, often fatal, complications of head injury, in survivors they do not seem to be related to later neuropsychological functioning.