Test-retest reliability and practice effects of a rapid screen of mild traumatic brain injury

Test-retest reliabilities and practice affects of measures from the Rapid Screen of Concussion (RSC), in addition to the Digit Symbol Substitution Test (Digit Symbol), were examined. Twenty five male participants were tested three times; each testing session scheduled a week apart. The test-retest reliability estimates for most measures were reasonably good, ranging from .79 to .97. An exception was the delayed word recall test, which has had a reliability estimate of .66 for the first retest, and .59 for the second retest. Practice effects were evident from Times 1 to 2 on the sentence comprehension and delayed recall subtests of the RSC, Digit Symbol and a composite score. There was also a practice effect of the same magnitude found from Time 2 to Time 3 on Digit Symbol, delayed recall and the composite score. Statistics on measures for both the first and second retest intervals, with associated practice affects, are presented to enable the calculation of reliable change indices (RCI). The RCI may be used to assess any improvement in cognitive functioning after mild Traumatic Brain Injury.

The acute effects of mild traumatic brain injury on finger tapping with and without word repetition

This study aimed to investigate the acute effects of mild Traumatic Brain Injury (mTBI) on the performance of a finger tapping and word repetition dual task in order to determine working memory impairment in mTBI Sixty-four (50 male, 14 female) right-handed cases of mTBI and 26 (18 male and 8 female) right-handed cases of orthopaedic injuries were tested within 24 hours of injury. Patients with mTBI completed fewer correct taps in 10 seconds than patients with orthopaedic injuries, and female mTBI cases repeated fewer words. The size of the dual task decrement did not vary between groups. When added to a test battery including the Rapid Screen of Concussion (RSC; Comerford, Geffen, May, Medland T Geffen, 2002) and the Digit Symbol Substitution Test,finger tapping speed accounted for 1% of between groups variance and did not improve classification rates of male participants. While the addition of tapping rate did not improve the sensitivity and specificity of the RSC and DSST to mTBI in males, univariate analysis of motor performance in females indicated. that dual task performance might be diagnostic. An increase in female sample Size is warranted. These results confirm the view that there is a generalized slowing of processing ability following mTBI.

Erosion-corrosion of mild steel in hot caustic. Part I: NaOH solution

A novel apparatus, high-pressure/high-temperature nickel flow loop, was constructed to study the effect of the flow on the rate of erosion-corrosion of mild steel in hot caustic. It has been successfully used to measure the corrosion rate of 1020 steel in 2.75 M NaOH solution at a temperature of 160 degrees C and velocities of 0.32 and 2.5 m/s. In situ electrochemical methods were used to measure the corrosion rate such as the potentiodynamic sweep, the polarization resistance method, and electrochemical impedance spectroscopy (EIS). Also used were the weight-loss method and scanning electron microscopy (SEM). Eight electrodes/coupons were used to monitor the metal loss rate, four were placed at the low velocity section, while the other four were placed in the high velocity section. The first three coupons in each section were placed within the disturbed flow region, while the fourth was placed in a fully developed flow region. The corrosion rate of the coupons in the high velocity section was generally higher than that of the coupons in the low velocity section. One coupon in the disturbed flow region had a significantly higher corrosion rate than the others. (c) 2005 Elsevier Ltd. All rights reserved.

Emergency department assessment of mild traumatic brain injury and prediction of post-concussion symptoms at one month post injury

Mild traumatic brain injury (mTBI) is a common injury and a significant proportion of those affected report chronic symptoms. This study investigated prediction of post-concussion symptoms using an Emergency Department (ED) assessment that examined neuropsychological and balance deficits and pain severity of 29 concussed individuals. Thirty participants with minor orthopedic injuries and 30 ED visitors were recruited as control subjects. Concussed and orthopedically injured participants were followed up by telephone at one month to assess symptom severity. In the ED, concussed subjects performed worse on some neuropsychological tests and had impaired balance compared to controls. They also reported significantly more post-concussive symptoms at follow-up. Neurocognitive impairment, pain and balance deficits were all significantly correlated with severity of post-concussion symptoms. The findings suggest that a combination of variables assessable in the ED may be useful in predicting which individuals will suffer persistent post-concussion problems.

Erosion-corrosion of mild steel in hot caustic. Part II: The effect of acid cleaning

Corrosion rates of 1020 steel in 2.75 M NaOH solution at a temperature of 160 degrees C and velocities of 0.32 and 2.5 m/s were studied. The focus was on the effect of the acid cleaning which was performed by using strong, inhibited sulphuric acid in between the exposures to caustic. In situ electrochemical methods were used to measure the corrosion rate such as the potentiodynamic sweep and the polarization resistance method. Also used were the weight-loss method and scanning electron microscopy (SEM). Eight electrodes/coupons were used to monitor the metal loss rate, four were placed at the low velocity section, while the other four were placed in the high velocity section of a high temperature flow. The first three coupons in each section were placed within the disturbed flow region, while the fourth was placed in a fully developed flow region. During the exposure of mild steel to the inhibited acid, following the first caustic period, the corrosion rate increased significantly to between 3 and 10mm/y with a few electrodes experiencing as high as 50 mm/y. The second caustic period following the acidic period typically started with very high corrosion rates (20-80 mm/y). The length of this corrosion period was typically 2-3 h with a few exceptions when the high corrosion period lasted 7-10 h. Following the very high corrosion rates experienced at the beginning of the second caustic period, the corrosion rates were reduced sharply (as the corrosion potential increased) to nearly the same levels as those observed during the passive part of the first caustic period. (c) 2005 Elsevier Ltd. All rights reserved.

Failure of normal glycaemic regulation in a patient with severe hypothermia

This report describes the case of an 88-year-old non-diabetic female who presented to the emergency department following a presumed hypoijtycaemic collapse due to self-neglect. Subsequent rewarming and resuscitation demonstrated a number of the significant consequences of severe hypothermia, including apparent secondary impairment of glycaemic autoregulation. The phenomenon of reversible inhibition of insulin secretion due to severe hypothermia has been documented previously in the field of cardiac surgery. The hyperglycaemia was not treated with any antihyperglycaernic agent, and her recovery was uneventful. Subsequent blood sugar level monitoring was normal. If insulin is administered to the hypothermic patient, intensive monitoring of blood glucose is essential due to the increase in endogenous insulin secretion on rewarming. (c) 2005 Elsevier Ireland Ltd. All rights reserved.

Psychometric assessment of recovery from mild traumatic brain injury

The Rapid Screen of Concussion (RSC) is a brief psychometric test battery, designed to provide a functional criterion to aid clinical diagnosis of mild traumatic brain injury (mTBI). The present research aimed to examine the utility of this instrument for assessing recovery after mTBI. Three studies were conducted. In Study 1, Discriminant Function Analysis was performed to determine how well the RSC differentiated uninjured controls (N¼16), from mTBI patients (N¼22) and moderate to severe TBI patients (N¼14), several months post-injury. As predicted, moderate to severe TBI patients achieved lower scores than the mTBI and control groups. The RSC also successfully differentiated between each of the diagnostic groups, yielding an overall correct classification rate of 75%. Study 2 examined the predictive utility of the RSC in the mTBI sample (N¼22). Acute injury performance on the RSC was correlated with post-injury scores at an average of 5.5 months post-injury. Statistically significant partial correlation coefficients (r¼0.53r¼0.80) were found for each of the subtests, showing that low acute RSC scores were predictive of poor recovery scores on the RSC after mTBI. In the third study, Reliable Change Indices were calculated on the RSC subtests to examine individual patterns of recovery from mTBI. While 17 of the 23 participants made a significant improvement on their acute injury DSST scores (74%), only 13 of 25 made a significant improvement on the Rapid Sentence Judgement Test (52%), highlighting differential recovery of function, and challenging the notion of full recovery from mTBI within 3 months. These overall results offer support for the construct and predictive validity of the RSC and demonstrate that inexpensive tests of brain function may be useful for managing mTBI acutely for prognosis.

Mini-dose glucagon rescue for mild hypoglycaemia in children with type 1 diabetes: The Brisbane experience

Objectives: To evaluate the use of small doses of glucagon using an insulin syringe in mild or impending hypoglycaemia in children with type 1 diabetes. Methods: Data were collected from patients attending the Paediatric Diabetes Clinic at the Queensland Diabetes Centre at the Mater Hospital, Brisbane in 2002-2004 following the institution of a new protocol for home management of mild or impending hypoglycaemia associated with inability or refusal to take oral carbohydrate. The protocol recommended the use of subcutaneous injections of glucagon using insulin syringes at a dose of two ' units ' (20 mu g) in children 2 years of age or younger, and for older children one unit per year of age up to a maximum of 15 units (150 mu g), with an additional doubled dose given if the blood glucose had not increased in 20 min. Results: Over a 2-year period, 25 children were treated with mini-dose glucagon on a total of 38 occasions. Additional doses were required for recurring hypoglycaemia on 20 (53%) occasions. The child could be managed at home on 32 (84%) of these 38 occasions, with only 6 (16%) children needing hospital treatment. Conclusions: Our study confirmed that small doses of glucagon given subcutaneously with an insulin syringe is a simple, practical and effective home treatment of mild or impending hypoglycaemia due to gastroenteritis or food refusal in children with type 1 diabetes.