[Heat stroke in the workplace: description of a case with fatal outcome]

BACKGROUND

Heat exposure represents an occupational risk factor in various work settings. Adverse effects may range from mild symptoms, like muscular cramps, to life threatening conditions, like heat stroke. Data on the occurrence of work-related adverse effects of heat exposure in Italy are lacking.

OBJECTIVES

To highlight the risk of heat stroke in a common working activity.

METHODS

The case of a fatal heat stroke in a 19-year-old worker, in apparently good health, employed in maintenance of open park spaces is presented. After working 7 hours outdoors on a sunny day he was found unconscious. He was immediately taken to the local Emergency Department, where he arrived in hyperthermic and comatose conditions, and died due to multiple organ failure after 36 hours. After excluding other main causes of hyperthermia, heatstroke was identified as the initial cause of death.

RESULTS

The case presented describes the possible extreme consequences of an underestimation of the risk related to occupational heat exposure, even in young and apparently healthy workers. Heat-related adverse effects may occur in a number of common activities, not necessarily involving heavy workload or extreme temperatures. Different methods, including simplified methods, are available for heat stress risk evaluation. The main preventive measures include adequate acclimatization, periodic interruption of exposure, sufficient fluid intake, adequate clothing and appropriate Personal Protective Equipment. Adequate training and workers' health surveillance are also essential.

CONCLUSIONS

Heat exposure may be a significant occupational risk, potentially inducing life-threatening conditions, in a number of common activities but is frequently underestimated. An example of undervaluation of the risk and of the possible consequences, are presented and discussed in this case report.

Prolonged neurological burden in severe lithium intoxication

A 53-year-old woman was brought to the Emergency Department for a persistent state of stupor, tremors, fever and oliguria. The patient had been under treatment for depression. The electrocardiogram showed a wider QRS complex; laboratory tests were as follows: urea 110 mg/dL, creatinine 3 mg/dL, sodium 135 mEq/L, potassium 4.5 mEq/L, and lithium 8.0 mEq/L. Renal replacement was initiated to normalize plasma lithium levels; both stupor and speech impairment persisted for several days after dialysis. Complete recovery was achieved several days afterwards.

[Influence of non-occupational sources on the levels of biomarkers of internal dose for use in biological monitoring of occupational exposure to extremely low concentrations of benzene]

OBJECTIVES

To study how traditional (t,t-muconic acid--t,t-MA and S-phenylmercapturic--SPMA) and new (urinary benzene) urinary biomarkers of internal dose can contribute to exclude an occupational source of exposure to extremely low concentrations of benzene, also analyzing the influence that non-occupational sources of exposure, such as cigarette smoking and urban pollution, can have on the levels of these biomarkers.

MATERIALS AND METHODS

Assessment was made of 6 workers employed at a groundwater purification plant polluted by benzene (exposed) and 6 administrative clerks employed at the same plant (controls); both groups included smokers and non-smokers. Environmental monitoring (fixed and personal samplings lasting 8 hours) and biological monitoring (determinations of t,t-MA, SPMA, urinary benzene, and urinary creatinine so as to apply suitable adjustments) were performed in exposed workers on 10 successive days, including also rest days (background exposure), and in controls only once.

RESULTS

Airborne benzene always resulted lower than the limit of detection of the analytical method in both fixed and personal samplings done on exposed workers and controls during working days, while personal samplings done on exposed workers during rest days showed benzene concentrations even higher than 5 microg/m3, that is the limit value for ambient air quality. Concentrations of t,t-MA, SPMA and urinary benzene did not show differences between exposed workers, regardless of whether they were studied on working or rest days, and controls and appeared to be largely within the reference value range for the Italian population. All biomarkers of internal dose examined in the study showed significantly higher values in smokers than non-smokers. In the latter, SPMA was always below the limit of detection, while urinary benzene resulted higher than the limit of detection in 60.0% and 87.5% of the determinations done on working and on rest days, respectively.

CONCLUSIONS

In situations of occupational exposure to extremely low doses of benzene or of absence of exposure, the application of an integrated environmental--biological monitoring approach, involving the determination of SPMA and/or urinary benzene, together with a careful evaluation of those factors determining non-occupational exposure to the toxicant, seems indispensable in order to be able to exclude the presence of occupational exposure. In these particular situations of occupational exposure to benzene, the interpretation of the results of environmental and biological monitoring should not only consider the TLV or BEI, but also the limit value for ambient air quality and the reference value for the general population, since benzene is able to determine genotoxic carcinogenic effects even at exposure to extremely low concentrations of the toxicant.

[Analysis of the active components of a complex intervention for the care management of stroke patients: impact on in-hospital mortality]

We conducted a cohort observational study in 29 Italian hospitals to identify which factors of the acute care management process of ischemic stroke patient can reduce in-hospital mortality. This complex intervention is based on some potential organizational and clinical active components, so data are collected both at organizational unit and individual patient level. We built the variables in relation to presence/absence of clinical-demographic, care-process and organizational characteristics. We compared categorical variables and evaluated the studied independent variables effects on the in-hospital mortality risk at 7 and 30 days from admission. One of the main care success determinants is to be admitted in a stroke unit during the acute-stroke-phase. The most important organizational factor is to be short-time assessed by a stroke team: active role in patients' needs evaluation is provided by the stroke specialists' multidisciplinary team. Antithrombotic therapy is influencing mortality at 7 and 30 days likewise: it is a indispensable factor for the clinical protocols. Our study emphasizes the fact that higher access to different and integrated levels of organized care is associated to better stroke outcomes and that some active and interactive components of the patient's care management have to be identified in the complex intervention.

Effects of clinical pathways in the joint replacement: a meta-analysis

BACKGROUND

A meta-analysis was performed to evaluate the use of clinical pathways for hip and knee joint replacements when compared with standard medical care. The impact of clinical pathways was evaluated assessing the major outcomes of in-hospital hip and knee joint replacement processes: postoperative complications, number of patients discharged at home, length of in-hospital stay and direct costs.

METHODS

Medline, Cinahl, Embase and the Cochrane Central Register of Controlled Trials were searched. The search was performed from 1975 to 2007. Each study was assessed independently by two reviewers. The assessment of methodological quality of the included studies was based on the Jadad methodological approach and on the New Castle Ottawa Scale. Data analysis abided by the guidelines set out by The Cochrane Collaboration regarding statistical methods. Meta-analyses were performed using RevMan software, version 4.2.

RESULTS

Twenty-two studies met the study inclusion criteria and were included in the meta-analysis for a total sample of 6,316 patients. The aggregate overall results showed significantly fewer patients suffering postoperative complications in the clinical pathways group when compared with the standard care group. A shorter length of stay in the clinical pathway group was also observed and lower costs during hospital stay were associated with the use of the clinical pathways. No significant differences were found in the rates of discharge to home.

CONCLUSION

The results of this meta-analysis show that clinical pathways can significantly improve the quality of care even if it is not possible to conclude that the implementation of clinical pathways is a cost-effective process, because none of the included studies analysed the cost of the development and implementation of the pathways. Based on the results we assume that pathways have impact on the organisation of care if the care process is structured in a standardised way, teams critically analyse the actual organisation of the process and the multidisciplinary team is highly involved in the re-organisation. Further studies should focus on the evaluation of pathways as complex interventions to help to understand which mechanisms within the clinical pathways can really improve the quality of care. With the need for knee and hip joint replacement on the rise, the use of clinical pathways might contribute to better quality of care and cost-effectiveness.

Frequency and clinical features of Lewy body dementia in Italian memory clinics

BACKGROUND

The latest developments in Lewy Body Dementia (DLB) raise some controversies on clinical features, neuroimaging and therapy. The aim of our study is to determine clinical, neuropsychological, neuroimaging and EEG profile of DLB through retrospective and prospective data of 102 patients.

METHODS

data were collected with an analytical form that was developed by an expertise of neurologists.

RESULTS

DLB represented 4.8% of the dementia population, with no sex difference. Family history of dementia was common (24.5%), while familiarity for parkinsonism was rare (4.9%). Cognitive disturbances were the predominant clinical presentation at onset (49%), followed by behavioral symptoms (29.4%) and parkinsonism (21.6%). Clinical features at consultation were: memory disturbances (almost all cases), symmetrical (68.6%) or asymmetrical (18.6%) parkinsonism, cognitive fluctuations (49%), visuospatial deficits (53.9%), and visual hallucinations (44.1%). Autonomic signs were present in a third of the cases, while sleep disorders were present in 44.1%. Some clinical response to antiparkinsonian drugs was evident in half of the cases. MRI, SPET, EEG and Neuropsychiatric Inventory data were available in a subgroup of patients.

CONCLUSIONS

Most of our data were in accordance with the previous literature. However, some data underline the relationship between DLB, Alzheimer's and Parkinson's disease.

3-Tesla MRI for the evaluation of myocardial viability: a comparative study with 1.5-Tesla MRI

PURPOSE

We compared 3-Tesla (3-T) and 1.5-Tesla (1.5-T) cardiac magnetic resonance imaging (MRI) for the assessment of myocardial viability in nearly identical experimental conditions.

MATERIALS AND METHODS

Thirty-five patients (mean age 63+/-11; 94.2% men) submitted to primary coronary angioplasty underwent both 3-T and 1.5-T cardiac MRI, which was considered the gold standard. Comparison was performed on the basis of the same viability imaging protocol, which included resting cine-MR [balanced fast-field echo (B-FFE) sequence] followed by contrast-enhanced MR to evaluate perfusion and delayed enhancement (DE). We then performed functional index measurements and visual estimation of kinesis, perfusion and DE referring to a 5-point scale. Image quality was assessed on the basis of signal to noise ratio (SNR) and contrast to noise ratio (CNR).

RESULTS

We found nonsignificant differences between the two scanners (P=NS) in measuring the functional and viability parameters. Myocardial SNR was significantly higher with 3-T MRI compared with 1.5-T MRI (61.3% gain). Even though a loss of CNR was recorded in B-FFE and in first-pass perfusion sequences (12.4% and 23.7%, respectively), on DE images, we quantified the increase of SNR and CNR of infarction of 387.8% and 330%, respectively.

CONCLUSIONS

We found that 3-T MRI showed high concordance with 1.5-T MRI in the evaluation of functional and viability parameters and provided better evidence of damaged myocardium.

[Risk management: the opinions of nursing staff and coordinators in a local health district in the Piemonte region (Italy)]

Clinical risk management includes a set of clinical and administrative activities performed to identify, evaluate and reduce risks for patients, staff and visitors as well as the organization itself. The first fundamental step in risk management is to evaluate risk factors; it is impossible to implement corrective actions and modify and eliminate risk factors if these are not known. The aim of this study was to evaluate the degree to which selected sentinel events were perceived by nursing staff as being severe and whether the degree of perceived severity of an event was associated with specific variables such as nursing work area (medical, surgical, intensive care), years of experience, degree and position. The study also aimed to evaluate the level of knowledge of clinical risk management, identify the main categories of errors within the organization, and evaluate nursing staff opinions on the use of an anonymous system to report errors. A sample of 98 nurses (91 female, 7 male), working in three hospitals in a local health district in the Piemonte region (Italy) participated in the study. The mean age of participants was 37 years (range 22-61). Participants were interviewed between 30 October and 6 November 2006, by using a structured questionnaire. Most participants (93%) were aware of the definition of risk management but over 60% did not use any tool for identifying clinical errors. Nurses perceived infections to be the most serious error, followed by medication errors and surgery and post-operative complications. Almost all participants (99%) considered it right to report errors and 59% admitted to having made errors, most frequently medication errors. Over 90% of participants agreed that an anonymous report form should be used for reporting. Healthcare professionals' willingness to cooperate and their ability to not play down the importance of sentinel events but rather voluntarily bring these to light are essential to the success of risk management in an organization. Clearly, patient safety does not depend on the single individual but rather on an interdisciplinary approach to problem notification and solving and collaboration among interdisciplinary team members.

Isolated porcine bronchi provide a reliable model for development of bronchodilator anti-muscarinic agents for human use

BACKGROUND AND PURPOSE

In human airways, muscarinic acetylcholine receptors (mAChRs) exert a predominant role in the control of airways resistance and anti-muscarinic agents are currently included in the pharmacological treatment of chronic obstructive pulmonary disease (COPD). However, the development of more effective mAChR antagonists is hampered by considerable species variability in the ultrastrucural and functional control of airway smooth muscle, making extrapolation of any particular animal model questionable. This study was designed to characterize the mAChRs in a bronchial preparation from pigs, animals considered to provide close models of human biology.

EXPERIMENTAL APPROACH

Smooth muscle bronchial strips were examined by electron microscopy in order to compare their neuromuscular structure with that of human bronchi and used to study the affinity of a series of selective mAChR antagonists, estimated as pKis in competition binding assays with NMS and pA2, by Schild analysis, in contractile experiments.

KEY RESULTS

Pharmacodynamic binding parameters and affinity profiles of a series of antagonists were consistent with the presence of a majority of M2 mAChRs along with a minor population of M3 mAChRs. Functionally, the highly significant correlation between postjunctional pA2 affinities and corresponding affinity constants at human recombinant M1-M5 subtypes indicated that smooth muscle contraction in porcine bronchi, as in human bronchi, was dependent on the M3 subtype.

CONCLUSION AND IMPLICATIONS

Based on the characterization of mAChRs, isolated porcine bronchi provide an additional experimental model for development of mAChR antagonists for the treatment of human airway dysfunctions.

[Quality of central venous catheter management protocols in Oncology centres of an Italian region]

The aim of this study was to evaluate the quality of central venous catheter (Port-a-cath, Groshong and Hohn) management protocols in Oncology centres in an Italian region. A retrospective study was performed in 25 hospitals, only 10 of which provided evidence that they utilized a central venous catheter management protocol. The submitted protocols were evaluated in terms of completeness and of adherence to manufacturers' indications and to recommendations of the Centre for Diseases Control. Study results show that overall, there is poor adherence to the basic quality requirements considered and only two of the ten protocols examined were found to be complete. Also, there is wide variability between the protocols with significant differences in the type of instructions provided in the different hospitals.

Peri-operative respiratory failure in a cirrhotic patient: a misleading diagnosis

Patients with chronic liver disease may present with different degrees of respiratory dysfunction whose differential diagnosis is important before elective surgery. We report the case of a misleading diagnosis of peri-operative respiratory failure in a cirrhotic patient who underwent mastectomy. Intra-operative respiratory failure was ascribed by the anaesthetic team to pulmonary embolism and after the operation this diagnosis was still suspected. Despite postoperative heparin treatment, pulmonary gas exchange remained severely impaired. On the hypothesis of a right to left shunt, we performed transoesophageal echocardiography with a bubble test and confirmed hepatopulmonary syndrome. We administered anticoagulant therapy to the patient following surgery, increasing the risk of haemorrhage. We also continued orotracheal intubation and mechanical ventilation longer than was needed. Respiratory symptoms in a patient with liver disease should not be underestimated and up to 20% of these patients may have hepatopulmonary syndrome.

[Influence of cigarette smoking on the excretion of urinary benzene in filling-station attendants]

The influence of cigarette smoking on concentrations of urinary benzene, a sensitive and specific biomarker proposed for biological monitoring of exposure to very low doses of benzene, was investigated in 24 filling-station attendants and 31 workers non occupationally exposed to benzene. Environmental monitoring was performed by personal passive samplers "Radiello", and a spot urine sample was collected at the end of the work shift, from all subjects, for the determination of urinary benzene. Exposure to benzene resulted significantly higher in filling-station attendants (mean 23.3 +/- 17.0 microg/m3; range 4.5-66.3 microg/m3) than in controls (mean 4.6 +/- 2.6 microg/m3; range < 3-11.5 microg/m3), while concentrations of urinary benzene did not show any significant difference between the two groups. Considering all subjects as a single group, it was observed that urinary benzene concentrations were positively correlated with the number of cigarettes smoked during the sampling time (rho = 0.38; p = 0.047) and with airborne benzene levels (rho = 0.32; p = 0.019), and negatively correlated with the time elapsed between the last smoked cigarette and urine collecting (rho = -0.40; p = 0.045). Multiple regression analysis confirmed the influence of cigarette smoking on urinary benzene concentrations. In conclusion, our study showed the validity of urinary benzene as a biomarker for biological monitoring of exposure to very low doses of benzene, although cigarette smoking determined a prevalent etiological role at the low environmental benzene concentrations observed.

Patients with macroprolactinaemia: clinical and radiological features

BACKGROUND

Macroprolactinaemia may represent a relevant cause of misdiagnosis, unnecessary investigation and inappropriate treatment. The aim of this study was to investigate the clinical and neuroradiological characteristics of patients with and without macroprolactinaemia and to evaluate the impact of macroprolactin determination on the diagnostic work-up of hyperprolactinaemic patients.

MATERIALS AND METHODS

Retrospective analysis in 135 consecutive hyperprolactinaemic patients (111 women and 24 men; mean age 37 +/- 11.6 years) whose archived sera were subsequently tested for macroprolactin. Recoveries </= 40% after polyethylene glycol precipitation were indicative of macroprolactinaemia.

RESULTS

Macroprolactin, entirely explaining biochemical hyperprolactinaemia, was found in 42.2% of patients, a third of whom presented with signs and symptoms of hyperprolactinaemia. Determination of macroprolactin changed the initial diagnosis in a consistent proportion of patients. In particular, idiopathic hyperprolactinaemia, initially diagnosed in 41 patients, was then excluded in 28 of them. Diagnosis of prolactin-secreting pituitary microadenoma shifted to non-secreting pituitary microadenoma in 10 of 49 patients, while in all patients with prolactin-secreting pituitary macroadenoma or hyperprolactinaemia due to stalk deafferentation the presence of macroprolactin was excluded and the initial diagnosis confirmed. Finally, macroprolactin was present in the majority of patients with magnetic resonance imaging (MRI) scans suggestive for primary empty sella (4 of 5 women) or pituitary hyperplasia (12 of 17 women, 3 of 3 men). Collectively, about half of subjects with macroprolactinaemia showed variable MRI abnormalities.

CONCLUSIONS

The presence of macroprolactin was a relevant cause of misdiagnosis in patients with hyperprolactinaemia. However, due to the unexpected high frequency of pituitary abnormalities observed in the present series, we suggest that the diagnostic algorithm of hyperprolactinaemic states should include both polyethylene glycol precipitation test and MRI imaging.

[Biological monitoring of exposure to benzene, toluene and xylenes in urban traffic wardens by LC-MS analysis]

Benzene, toluene and xylenes (BTX) are aromatic hydrocarbons widely used as industrial chemicals. Due to their formation in many combustion processes, they are widespread environmental pollutants. Thus, the general population undergoes lifelong exposure to these pollutants, and some categories of workers are exposed at particularly high levels. In order to evaluate human exposure to BTX, mercapturic acids (MA) have recently been proposed as the most specific biomarkers, but only S-phenyl mercapturic acid (S-PMA) has been validated as a biomarker for benzene. Furthermore, S-benzyl mercapturic acid (S-BMA) and S-benzyl methyl mercapturic acid (S-BMMA), metabolites of toluene and o-xylene, respectively, have been less extensively investigated. In this paper, we evaluated exposure to BTX in a group of 354 traffic wardens by measuring the urinary concentration of S-PMA, S-BMA and S-BMMA using a method based on liquid-chromatography-tandem mass spectrometry. This analytical method was fully validated according to U.S. Food and Drug Administration guidance. All samples showed a measurable concentration of S-BMA (mean: 12.84 microg/g (creatinine)), while S-PMA and S-BMMA resulted quantifiable only in about 30% of the analyzed urines (mean: 1.76 and 3.98 microg/g(creatinine), respectively).

Inhibition of the SH3 domain-mediated binding of Src to the androgen receptor and its effect on tumor growth

In human mammary and prostate cancer cells, steroid hormones or epidermal growth factor (EGF) trigger association of the androgen receptor (AR)-estradiol receptor (ER) (alpha or beta) complex with Src. This interaction activates Src and affects the G1 to S cell cycle progression. In this report, we identify the sequence responsible for the AR/Src interaction and describe a 10 amino-acid peptide that inhibits this interaction. Treatment of the human prostate or mammary cancer cells (LNCaP or MCF-7, respectively) with nanomolar concentrations of this peptide inhibits the androgen- or estradiol-induced association between the AR or the ER and Src the Src/Erk pathway activation, cyclin D1 expression and DNA synthesis, without interfering in the receptor-dependent transcriptional activity. Similarly, the peptide prevents the S phase entry of LNCaP and MCF-7 cells treated with EGF as well as mouse embryo fibroblasts stimulated with androgen or EGF. Interestingly, the peptide does not inhibit the S phase entry and cytoskeletal changes induced by EGF or serum treatment of AR-negative prostate cancer cell lines. The peptide is the first example of a specific inhibitor of steroid receptor-dependent signal transducing activity. The importance of these results is highlighted by the finding that the peptide strongly inhibits the growth of LNCaP xenografts established in nude mice.