The impact of fatigue on the non-technical skills performance of critical care air ambulance clinicians.

BACKGROUND: The relationship between fatigue-related risk and impaired clinical performance is not entirely clear. Non-technical factors represent an important component of clinical performance and may be sensitive to the effects of fatigue. The hypothesis was that the sum score of overall non-technical performance is degraded by fatigue. METHODS: Nineteen physicians undertook two different simulated air ambulance missions, once when rested, and once when fatigued (randomised crossover design). Trained assessors blinded to participants' fatigue status performed detailed structured assessments based on expected behaviours in four non-technical skills domains: teamwork, situational awareness, task management, and decision making. Participants also provided self-ratings of their performance. The primary endpoint was the sum score of overall non-technical performance. RESULTS: The main finding, the overall non-technical skills performance rating of the clinicians, was better in rested than fatigued states (mean difference with 95% CI, 2.8 [2.2-3.4]). The findings remained consistent across individual non-technical skills domains; also when controlling for an order effect and examining the impact of a number of possible covariates. There was no difference in self-ratings of clinical performance between rested and fatigued states. CONCLUSION: Non-technical performance of critical care air transfer clinicians is degraded when they are fatigued. Fatigued clinicians may fail to recognise the degree to which their performance is compromised. These findings represent risk to clinical care quality and patient safety in the dynamic and isolated environment of air ambulance transfer.

Multiple stressor effects of herbicide, pH, and food on wetland zooplankton and a larval amphibian.

Interactions of herbicides and natural environmental stressors such as pH and food availability are poorly understood. We tested a chemical formulation of triclopyr (Release) at environmentally relevant test concentrations (0.25 and 0.50 mg L(-1)) in combination with two levels of pH (pH 5.5 and 7.5), and two levels of food availability (high and low). Population level effects of each stressor alone and in combination with the others were investigated using Simocephalus vetulus, a zooplankton species, and Rana pipiens tadpoles (Gosner stage 25), both common to forest ponds and wetlands. Herbicide treatments resulted in significant decreases in survival of both test species as well as reproduction and development time for S. vetulus at levels 5-10x below predicted worst case environmental concentrations (2.6 mg L(-1)). This laboratory study demonstrates a probable risk of toxic effects of Release herbicide which may be significantly increased by low food availability and by low pH at environmentally relevant concentrations.

Randomized effectiveness study of four therapeutic strategies for TMJ closed lock.

For individuals with temporomandibular joint (TMJ) disc displacement without reduction with limited mouth opening (closed lock), interventions vary from minimal treatment to surgery. In a single-blind trial, 106 individuals with TMJ closed lock were randomized among medical management, rehabilitation, arthroscopic surgery with post-operative rehabilitation, or arthroplasty with post-operative rehabilitation. Evaluations at baseline, 3, 6, 12, 18, 24, and 60 months used the Craniomandibular Index (CMI) and Symptom Severity Index (SSI) for jaw function and TMJ pain respectively. Using an intention-to-treat analysis, we observed no between-group difference at any follow-up for CMI (p > or = 0.33) or SSI (p > or = 0.08). Both outcomes showed within-group improvement (p < 0.0001) for all groups. The findings of this study suggest that primary treatment for individuals with TMJ closed lock should consist of medical management or rehabilitation. The use of this approach will avoid unnecessary surgical procedures.

Thrombophilia testing in patients with venous thrombosis.

BACKGROUND: Routine thrombophilia testing is controversial because of the low yield of positive tests, costs involved, and debate about the clinical usefulness of the data obtained from testing. Laboratory investigations are rarely done for those with superficial venous thrombosis (SVT) or isolated calf vein thrombosis (CVT) which are often not treated with anticoagulants. OBJECTIVE: To identify the incidence of markers of thrombophilia in patients with deep vein thrombosis (DVT), SVT, isolated CVT or a history of thrombosis in a referral practice. METHODS: One hundred and sixty-six patients were referred to our thrombosis unit for consultation, including patients with SVT, DVT, and preoperative patients with a previous history of SVT or DVT. Patients underwent thrombophilia screening and patients with a diagnosis of SVT or DVT were confirmed by bilateral duplex ultrasonography of all lower limb veins. Thrombophilia testing included factor V Leiden (FVL), prothrombin 20210A mutation (P2), methylene tetrahydrofolate reductase deficiency (MTHFR), fasting serum homocysteine (HC), lupus anticoagulant (LA), anticardiolipin antibodies (ACA), antithrombin deficiency (AT), protein S deficiency (PS), and protein C deficiency (PC). RESULTS: The incidence of any significant abnormality in patients with DVT was 27/44 (61%; 95% Confidence interval [CI], 47-76%) and 10 of these patients were positive for FVL (23%; 95% CI, 10-35%). Twelve patients with isolated CVT were seen and five had at least one abnormality (42%; 95% CI, 14-70%) including one with FVL (8%; 95% CI, 0-24%). Thirty-nine patients with isolated SVT were seen including 14 with at least one abnormality (36%; 95% CI, 21-51%) and five of these patients with SVT had FVL (13%; 95% CI, 2-23%). Nine patients with recurrent DVT were seen and five of these had at least one abnormal test (56%; 95% CI, 23-88%). Finally, 18 of the 166 patients had more than one abnormality (11%; 95% CI, 6-16%). CONCLUSION: The presence of one or more markers of thrombophilia was significantly higher in this patient population compared to reports from other centres. This study identified 18/166 (10.8%; 95% CI, 6-16%) with more than one defect where life-long anticoagulation might be considered. The results in this subset of patients as well as the serious defects found in some patients with provoked DVT, isolated CVT or isolated SVT demonstrate the value of this screening program to both these patients and their blood relatives. On the other hand, this is a small series from a referral practice where the incidence of these defects is greater than one would expect in the general population. These studies are preliminary and it is not recommended that all VTE patients should be screened on the basis of the current report.

Social network mapping with transplant recipients.

Social support can have great influence on health, well-being, and general quality of life To promote awareness of the social network that surrounds each transplant recipient, transplant social workers are now using the Social Network Map as an intervention. Because perceptions of availability and accessibility of support are key elements in the use of social network resources, awakening an individual's awareness of available resources is a significant first step in enhancing social support and, ultimately, quality of life. The Social Network Map is used to establish dialogue regarding individuals' needs and sources of support, and then how the support system can meet those needs. Transplant social workers thus foster active use of those people in transplant recipients' networks who can meet the particular needs recipients identify.

Evaluation and management of maladaptive behaviors and psychological issues in temporomandibular disorder patients.

This article presents an overview of some of the behavioral and psychosocial issues involved in the care of TMJ and orofacial pain patients. The importance of a thorough pretreatment assessment is emphasized. Treatment options for oral habits, stress management, and other psychosocial challenges are briefly discussed.

Psychometric profiles and related pain characteristics of temporomandibular disorder patients.

The psychological characteristics of patients with temporomandibular disorders have received much attention in the literature. A multivariate clustering technique has been used in the study of psychological characteristics of other chronic pain conditions, and this has recently been applied to "temporomandibular joint pain" patients to develop homogeneous psychometric subgroups. The primary objective of this study was to determine if these subgroups could be replicated in a separate sample. A group of 109 consecutive patients, presenting with complaints of jaw pain, were administered a Symptom Checklist-90 Revised and a questionnaire regarding characteristics of the pain complaint. A multivariate clustering technique was used to identify three discrete psychometric subgroups, as in previous studies. Although similar, these subgroups were not identical to those of previous studies. The small number of subjects in the psychometrically abnormal subgroup was of special interest.

Schistosoma mansoni: single-step purification and characterization of glutathione S-transferase isoenzyme 4.

A soluble glutathione S-transferase isoenzyme, designated SmGST-4 was purified to apparent homogeneity in a single step from the cytosol of adult Schistosoma mansoni by selective elution of the enzyme from a glutathione-agarose affinity column using glutathione disulfide. SmGST-4, which comprised about 5% of the bound glutathione S-transferase activity, could be distinguished from the previously characterized glutathione S-transferase isoenzyme family (SmGST-1/2/3), by its unique chromatographic behavior, lower subunit M(r) (26,000), differences in substrate specificity and inhibitor sensitivity, and a lack of reactivity with antiserum to SmGST-3. The purified isoenzyme catalyzed the conjugation of several model xenobiotics including 1-chloro-2,4-dinitrobenzene, ethacrynic acid, and trans-4-phenyl-3-buten-2-one. Like the SmGST-1/2/3 isoenzyme family, SmGST-4 failed to catalyze the conjugation of a model epoxide substrate, 1,2-epoxy-3-(p-nitrophenoxy)propane. Because glutathione S-transferases from other organisms play a role in protecting cells against the toxic products of lipid peroxidation, SmGST-4 and the members of the SmGST-1/2/3 isoenzyme family were tested for their capacity to reduce cumene hydroperoxide and to catalyze the conjugation of 4-hydroxyalk-2-enals. Although all four isoenzymes catalyzed both reactions, the specific activity of SmGST-1, SmGST-2, and SmGST-3 toward cumene hydroperoxide was at least 10-fold greater than that of SmGST-4. In contrast, the latter more effectively conjugated a homologous series of 4-hydroxyalk-2-enal isomers.(ABSTRACT TRUNCATED AT 250 WORDS)

Individual differences in motor skills ability affect the self-regulation of heart rate.

Twenty males who scored relatively high on the rotor-pursuit motor skills task (High performance group) were given seven 2-minute trials to increase heart rate and seven 2-minute trials to decrease heart rate, as were 20 males who scored relatively low on the rotor-pursuit task (Low performance group). Visual analogue feedback was not provided during the first and last acceleration and deceleration trials but was presented during all other trials. Both groups of subjects were able to decrease heart rate significantly with and without feedback. Subjects in the High performance group were able to increase heart rate significantly with feedback and could generalize this increase to a no-feedback trial following feedback trials. Subjects in the Low performance group could not increase heart rate with or without feedback. Changes in respiration rate paralleled those noted for heart rate, but changes in chin electromyographic activity generally did not parallel the heart rate results. The heart rate data are discussed in terms of motor skills theories of self-regulation of heart rate.