Impact of intensive care unit relocation and role of tap water on an outbreak of Pseudomonas aeruginosa expressing OprD-mediated resistance to imipenem

BACKGROUND

To assess the impact of the incidental relocation of an intensive care unit (ICU) on the risk of colonizations/infections with Pseudomonas aeruginosa exhibiting OprD-mediated resistance to imipenem (PA-OprD).

AIM

The primary aim was to compare the proportion of PA-OprD among P. aeruginosa samples before and after an incidental relocation of the ICU. The role of tap water as a route of contamination for colonization/infection of patients with PA-OprD was assessed as a secondary aim.

METHODS

A single-centre, observational, before/after comparison study was conducted from October 2013 to October 2015. The ICU was relocated at the end of October 2014. All P. aeruginosa-positive samples isolated from patients hospitalized ≥48 h in the ICU were included. Tap water specimens were collected every three months in the ICU. PA-OprD strains isolated from patients and tap water were genotyped using pulse-field gel electrophoresis.

FINDINGS

A total of 139 clinical specimens of P. aeruginosa and 19 tap water samples were analysed. The proportion of PA-OprD strains decreased significantly from 31% to 7.7% after the relocation of the ICU (P = 0.004). All PA-OprD clinical specimens had a distinct genotype. Surprisingly, tap water was colonized with a single PA-OprD strain during both periods, but this single clone has never been isolated from clinical specimens.

CONCLUSION

Relocation of the ICU was associated with a marked decrease in P. aeruginosa strains resistant to imipenem. The polyclonal character of PA-OprD strains isolated from patients and the absence of tap-water-to-patient contamination highlight the complexity of the environmental impact on the endogenous colonization/infection with P. aeruginosa.

Toxigenic Corynebacterium ulcerans in a fatal human case and her feline contacts, France, March 2014

In March 2014, a person in their eighties who was diagnosed with extensive cellulitis due to toxigenic Corynebacterium ulcerans died from multiple organ failure. Environmental investigation also isolated C. ulcerans in biological samples from two stray cats in contact with the case. This finding provides further evidence that pets can carry toxigenic C. ulcerans and may be a source of the infection in humans.

Diagnostic accuracy of urinary dipstick to exclude catheter-associated urinary tract infection in ICU patients: a reappraisal

OBJECTIVES

We wanted to assess the diagnostic accuracy of urinary dipstick testing in excluding catheter-associated urinary tract infection (CAUTI) in intensive care unit (ICU) patients with fever or hypothermia.

METHODS

This was a prospective observational cohort study in a medical-surgical ICU. Patients with new-onset fever >38.3 °C or hypothermia <36 °C at least 48 h after urinary catheter insertion were included over a 2-year period. At each episode, a urinary dipstick test and a urine culture were performed as the criterion standard. Extensive microbiological investigations for extra-urinary infections were performed also. The performances of various urinary dipstick result combinations in ruling out CAUTI were compared based on the likelihood ratios (LR+ and LR-).

RESULTS

Symptomatic CAUTI was diagnosed in 31 (24.4 %) of the 127 included patients (195 episodes of fever or hypothermia). LR+ was best for combined leukocyte esterase-positive and nitrite-positive dipstick results (overall population: 14.91; 95 % confidence interval [95 % CI], 5.53-40.19; patients without urinary symptoms: 15.63; 95 % CI, 5.76-42.39). LR- was best for either leukocyte esterase-positive or nitrite-positive dipstick results (overall population: 0.41; 95 % CI, 0.57-0.65; patients without urinary symptoms, 0.36; 95 % CI, 0.21-0.60).

CONCLUSIONS

Urinary dipstick testing at the bedside does not help to rule out symptomatic CAUTI in medical or surgical ICU patients with fever or hypothermia.

[Prevalence of dysphosphoremia in patients admitted in intensive care unit with an impaired renal function]

OBJECTIVE

To assess the frequency of dysphosphoremia in patients admitted in intensive care unit with an impaired renal function and to determine the associated risks factors. Study design. - Epidemiological prospective study.

PATIENTS AND METHODS

The creatinine clearance and the phosphoremia were measured in 134 consecutive patients admitted in intensive care unit over a six-month period. Patients with chronic renal failure were excluded. Known risk factors for hypophosphoremia in intensive care unit were recorded.

RESULTS

Seventy-nine out of one hundred thirty-four patients (59%) had an impaired renal function (arbitrarily defined by a creatinine clearance < 60 ml/min). The proportion of patients with impaired renal function that where hypo-, normo- (0.8 to 1.2 mmol/l) or hyperphosphoremic was 16, 34 and 50% respectively. Hypophosphoremia was severe (< 0.5 mmol/l) in 5 patients, all with impaired renal function. No risk factors usually associated with hypophosphoremia could be identified.

CONCLUSION

As opposed to chronic renal failure patients who are mainly hyperphosphoremic, patients admitted in intensive care unit with an impaired renal function may present with a normo-, or hypophosphoremia. These dysphosphoremias are sometimes severe. Phosphate status should be promptly determined at admission.

Accuracy of a composite score using daily SAPS II and LOD scores for predicting hospital mortality in ICU patients hospitalized for more than 72 h

In most databases used to build general severity scores the median duration of intensive care unit (ICU) stay is less than 3 days. Consequently, these scores are not the most appropriate tools for measuring prognosis in studies dealing with ICU patients hospitalized for more than 72 h.

PURPOSE

To develop a new prognostic model based on a general severity score (SAPS II), an organ dysfunction score (LOD) and evolution of both scores during the first 3 days of ICU stay.

DESIGN

Prospective multicenter study.

SETTING

Twenty-eight intensive care units (ICUs) in France.

PATIENTS

A training data-set was created with four ICUs during an 18-month period (893 patients). Seventy percent of the patients were medical (628) aged 66 years. The median SAPS II was 38. The ICU and hospital mortality rates were 22.7% and 30%, respectively. Forty-seven percent (420 patients) were transferred from hospital wards. In this population, the calibration (Hosmer-Lemeshow chi-square: 37.4, P = 0.001) and the discrimination [area under the ROC curves: 0.744 (95 % CI: 0.714-0.773)] of the original SAPS II were relatively poor. A validation data set was created with a random panel of 24 French ICUs during March 1999 (312 patients).

MEASUREMENTS AND MAIN RESULTS

The LOD and SAPS II scores were calculated during the first (SAPS1, LOD1), second (SAPS2, LOD2), and third (SAPS3, LOD3) calendar days. The LOD and SAPS scores alterations were assigned the value "1" when scores increased with time and "0" otherwise. A multivariable logistic regression model was used to select variables measured during the first three calendar days, and independently associated with death. Selected variables were: SAPS II at admission [OR: 1.04 (95 % CI: 1.027-1.053) per point], LOD [OR: 1.16 (95 % CI: 1.085-1.253) per point], transfer from ward [OR: 1.74 (95 % CI: 1.25-2.42)], as well as SAPS3-SAPS2 alterations [OR: 1.516 (95 % CI: 1.04-2.22)], and LOD3-LOD2 alterations [OR: 2.00 (95 % CI: 1.29-3.11)]. The final model has good calibration and discrimination properties in the training data set [area under the ROC curve: 0.794 (95 % CI: 0.766-0.820), Hosmer-Lemeshow C statistic: 5.56, P = 0.7]. In the validation data set, the model maintained good accuracy [area under the ROC curve: 0.826 (95 % CI: 0.780-0.867), Hosmer-Lemeshow C statistic: 7.14, P = 0.5].

CONCLUSIONS

The new model using SAPS II and LOD and their evolution during the first calendar days has good discrimination and calibration properties. We propose its use for benchmarking and evaluating the over-risk of death associated with ICU-acquired nosocomial infections.

[Severe pulmonary embolism with two indications for inferior vena cava filter placement]

A case of severe pulmonary embolism, treated with thrombolysis, and complicated by a haemorrhagic shock (peritoneal bleeding after a spleen trauma) is reported. A paradoxical renal artery embolism occurred, due to a patent foramen ovale. The benefit of a inferior vena cava filter insertion in case of paradoxical embolism is discussed.

A 3-level prognostic classification in septic shock based on cortisol levels and cortisol response to corticotropin

CONTEXT

The hypothalamic-pituitary-adrenal axis is a major determinant of the host response to stress. The relationship between its activation and patient outcome is not known.

OBJECTIVE

To evaluate the prognostic value of cortisol levels and a short corticotropin stimulation test in patients with septic shock.

DESIGN AND SETTING

Prospective inception cohort study conducted between October 1991 and September 1995 in 2 teaching hospital adult intensive care units in France.

PARTICIPANTS

A total of 189 consecutive patients who met clinical criteria for septic shock.

INTERVENTION

A short corticotropin stimulation test was performed in all patients by intravenously injecting 0.25 mg of tetracosactrin; blood samples were taken immediately before the test (T0) and 30 (T30) and 60 (T60) minutes afterward.

MAIN OUTCOME MEASURES

Twenty-eight-day mortality as a function of variables collected at the onset of septic shock, including cortisol levels before the corticotropin test and the cortisol response to corticotropin (delta max, defined as the difference between T0 and the highest value between T30 and T60).

RESULTS

The 28-day mortality was 58% (95% confidence interval [CI], 51%-65%) and median time to death was 17 days (95% CI, 14-27 days). In multivariate analysis, independent predictors of death (P < or = .001 for all) were McCabe score greater than 0, organ system failure score greater than 2, arterial lactate level greater than 2.8 mmol/L, ratio of PaO2 to fraction of inspired oxygen no more than 160 mm Hg, cortisol level at T0 greater than 34 microg/dL and delta max no more than 9 microg/dL. Three groups of patient prognoses were identified: good (cortisol level at T0 < or = 34 microg/dL and delta max > 9 microg/dL; 28-day mortality rate, 26%), intermediate (cortisol level at T0 34 microg/dL and delta max < or = 9 microg/dL or cortisol level at T0 > 34 microg/dL and delta max > 9 microg/dL; 28-day mortality rate, 67%), and poor (cortisol level at T0 > 34 microg/dL and delta max < or = 9 microg/dL; 28-day mortality rate, 82%).

CONCLUSION

Our data suggest that a short corticotropin test has a good prognostic value and could be helpful in identifying patients with septic shock at high risk for death.

[Regionalization of perinatal care and in utero referrals]

Further improvement in perinatal morbidity and mortality figures implies in utero referral so high risk infants, particularly very early maturity infants, can be managed immediately in specialized centers. The success of such referrals depends directly on the coherence of the regional perinatal health care network. It has been demonstrated that the chances of survival and of sequelae-free survival are greater for very premature infants born in a center with a neonatal intensive care unit. The situation in France leaves room for improvement. Only 15% of the infants born before 33 months gestation and with birth weight under 1500 g are born in level III maternity wards equipped with a neonatal intensive care unit. The goal is 80%. We have tried to analyze the reasons behind this situation and propose ways to better organize perinatal health care.

Is the duration of mechanical ventilation predictable?

BACKGROUND

Prolonged mechanical ventilation (MV) is associated with high morbidity, mortality, and cost. However, few and limited data are available on the prediction of duration of MV. We conducted an observational cohort study to seek predictive criteria.

METHODS

The study was performed in a surgical ICU (SICU) in a university hospital. One hundred ninety-five consecutive unselected patients and 203 episodes of MV were prospectively analyzed to determine if clinical features, physiologic parameters, or multifactor scoring systems, at the time of admission or intubation, could be used as predictors of MV > or = 15 days. A univariate statistical analysis and a multiple logistic regression were used. A prospective validation study was then conducted to determine the accuracy of the results.

RESULTS

(1) Univariate statistical analysis indicated that SICU length of stay, emergent endotracheal intubation as opposed to elective intubation, indication for MV, sepsis score at the time of admission and intubation, lung injury score (LIS) at the time of admission and intubation, number of organ system failures at the time of admission and intubation, and serum albumin concentration were significantly different between the two groups. (2) Only the circumstances (emergency) of endotracheal intubation (odds ratio [OR]=3.5, p=0.02) and the LIS (OR=3.7, p=0.004) independently predicted a duration of endotracheal intubation > or = 15 days. One hundred twenty-eight consecutive patients requiring emergent intubation and MV were included in the prospective validation. The accuracy of the LIS > or = 1 used to predict MV > or = 15 days was as follows: sensitivity=0.88; specificity=0.28; positive predictive value=0.24; negative predictive value=0.91.

CONCLUSION

Low incidence of MV > or = 15 days was observed (13% and 20%, respectively, in observational cohort study and validation study) in unselected SICU patients. LIS > or = 1 at the time of intubation provides excellent negative predictive value (0.93 and 0.91) of duration of MV > or = 15 days. These data suggest that tracheotomy should not be considered for patients with LIS < 1.

Acute pancreatitis and preeclampsia-eclampsia: a case report

A case of preeclampsia-eclampsia leading to acute edematous pancreatitis is reported, probably related to microvascular abnormalities and splanchnic ischemia. Recovery was uneventful.

Renal effects of low-dose dopamine in patients with sepsis syndrome or septic shock treated with catecholamines

OBJECTIVE

To evaluate the renal effects of low-dose dopamine in patients with sepsis syndrome or septic shock treated with catecholamines.

DESIGN

Prospective, clinical study using sequential periods.

SETTING

A 12-bed surgical intensive care unit in a university hospital.

PATIENTS

14 patients with sepsis syndrome and 15 patients with septic shock treated with exogenous catecholamines were studied. They had no diuretic treatment.

INTERVENTION

Two periods of 2 h each with and without 2 micrograms.kg-1.min-1 of dopamine infusion. Hemodynamic and renal data were obtained at the end of each period. Measurements were repeated after 48 h of dopamine infusion in patients with sepsis syndrome. All data were evaluated by the Wilcoxon rank test.

MEASUREMENTS AND RESULTS

In patients with sepsis syndrome, diuresis and creatinine clearance increased significantly by 100% and 60%, respectively, during low-dose dopamine infusion without any change in systemic hemodynamics. The renal response to dopamine decreased significantly after 48 h of dopamine infusion (P < 0.01). In patients with septic shock treated with catecholamines, no variation of either systemic hemodynamics or renal function was noted during low-dose dopamine infusion.

CONCLUSION

The renal effects of low-dose dopamine in patients with sepsis syndrome decrease with time. No renal effect of low-dose dopamine was observed in patients with septic shock treated with catecholamines. These findings suggest a desensitization of renal dopaminergic receptors.

High incidence of hypophosphatemia in surgical intensive care patients: efficacy of phosphorus therapy on myocardial function

OBJECTIVE

To determine the incidence of hypophosphatemia in a surgical intensive care unit and to determine whether or not a phosphorus challenge causes a change in cardiac performance in hypophosphatemic patients.

DESIGN

Prospective clinical study and case reports.

SETTING

Surgical intensive care unit in an university hospital.

PATIENTS

A total of 208 consecutive patients admitted to the surgical ICU were evaluated over a 6 months period.

INTERVENTIONS

All classical risk factors for hypophosphatemia were recorded. A group of 8 moderate or severe hypophosphatemic patients were evaluated for hemodynamic data before and after a phosphorus load. Glucose phosphate was given over 30 min by the intravenous route. Dosage regimen was 0.4 mmol/kg weight for moderate hypophosphatemia and 0.8 mmol/kg weight for severe hypophosphatemia.

RESULTS

Risk factors were present in 134 patients and 60 patients were hypophosphatemic (44.8%). Only 3 risk factors were discriminant for hypophosphatemia: sepsis, diuretics and total parenteral nutrition. The mortality was higher in the hypophosphatemic group than in the normophosphatemic group (30% versus 15.2%; p < 0.05). Cardiac performance improved after phosphatemia normalization in all patients (cardiac index: 3.82 +/- 1.87 versus 4.52 +/- 1.83 1/min.m2; p < 0.01).

CONCLUSION

This study underlines the high incidence (28.8%) of hypophosphatemia in surgical intensive care patients and its association with a high mortality rate (30%). A short course of phosphotherapy improves cardiac index (+18%).

Kinetics of elimination and acute consequences of cerebral air embolism

The pathophysiology of arterial air embolism inducing brain injuries remains unclear. Previous experiments demonstrated the usefulness of computed tomography (CT) in the detection of air emboli in canine brain. This canine study investigates CT's ability to detect small air bubbles and to determine the kinetics of air elimination from cerebral arteries and its relationship with clinical, electroencephalographic (EEG), and histological manifestations. CT detects small air embolism, and intracerebral air volume strongly correlates with injected air dose (r2 = 0.86, p = 2 x 10(-3)). Air clearance time significantly depends on intracerebral air volume (r2 = 0.86, p = 0.04) and on the number of bubbles (r2 = 0.71, p = 0.03), whereas half-life of air elimination does not. No relationship was found between injected air dose, air clearance time, intracerebral volume of air, and clinical, EEG, and histological findings. The data indicate that CT accurately detects small air bubbles in the early course of cerebral air embolism, that air elimination from cerebral arteries follows a first-order compartment model, and that early CT findings do not correlate with clinical, EEG, and histological manifestations.

Effects of mechanical ventilation with normobaric oxygen therapy on the rate of air removal from cerebral arteries

OBJECTIVE

We conducted the current study to evaluate the removal rate of air embolism from cerebral arteries after spontaneous breathing at a low FIO2 in comparison with mechanical ventilation at an FIO2 of 1.0.

DESIGN

Randomized, experimental trial.

SETTING

Neuroimaging department at a veterinary school hospital laboratory.

SUBJECTS

Nine anesthetized beagles undergoing mechanical ventilation with previous normal cranial computed tomography (CT) scan.

INTERVENTIONS

In each dog, after a control scan, air was infused at a constant flow rate, via a catheter inserted into the internal carotid artery. CT scan was repeated until typical bubbles appeared. Immediately after, the animals were randomly assigned to breathe room air (group A), or to be mechanically ventilated at an FIO2 of 1.0 (group B). CT scan was again repeated every minute until the removal of all bubbles. We compared the volume of air infused per kg of body and brain weights, the lowest density among bubbles (Hounsfield units), the duration of radiologic findings, and the ratio of volume/duration (mL/kg/min) between the two groups, using the Mann-Whitney test.

RESULTS

The volume of air infused per kg of body and brain weights and density were not significantly different between the two groups. The duration of radiologic findings was shorter (p < .02) in group B (7.0 +/- 4.7) than in group A (20.4 +/- 3.8), and the air removal rate from cerebral arteries (expressed as volume/duration of radiologic findings) was dramatically improved (p < .02) in group B (0.159 +/- 0.042) in comparison with group A (0.046 +/- 0.016).

CONCLUSIONS

These results suggest that the removal rate of air from cerebral arteries is dramatically increased by mechanical ventilation at an FIO2 of 1.0. Consequently, the time of cerebral ischemia may be decreased, but the result does not account for the effects of each factor separately. Further studies are required to evaluate the clinical benefits of high FIO2 administration and of mechanical ventilation separately. However, the prompt application of mechanical ventilation with an FIO2 of 1.0 may be recommended when air embolism is suspected.

Phlegmonous gastritis associated with HIV-1 seroconversion. Endoscopic and microscopic evolution

A 40-year-old man presented with peritonitis. Diagnosis of phlegmonous gastritis was made by laparotomy. Conservative treatment combined with antibiotics was successful. Multiple endoscopies with biopsies illustrate the natural history of this disease. The patient developed HIV-1 seroconversion during hospital stay. Prompt diagnosis and treatment may improve the prognosis of this often lethal disease.

[Severe methotrexate poisoning]

Methotrexate toxicity is rare but extremely severe. When complete, it consists of ulcerations of the gastrointestinal mucosae responsible for necrotizing enteritis, erythroderma, bone marrow aplasia, interstitial pneumonia, hepatitis and organic renal failure with diuresis. Toxicity is facilitated by pre-existing renal impairment, third sector and abstention or underdosage of foliculinic acid prescribed as antagonist. The diagnosis rests on serum assays, the results of which must be interpreted taking into account the assay method and the time elapsed between the injection of methotrexate and its assay in serum. The multivisceral pathology observed may totally regress, as in the case reported here. Treatment is based on symptomatic measures, starting with maintenance of an abundant and alkaline diuresis, and on the parenteral administration of folinic acid in doses that vary with the authors.