Smartphone monitoring of in-ambulance vibration and noise

Transferring sick premature infants between hospitals increases the risk of severe brain injury, potentially linked to the excessive exposure to noise, vibration and driving-related accelerations. One method of reducing these levels may be to travel along smoother and quieter roads at an optimal speed, however this requires mass data on the effect of roads on the environment within ambulances. An app for the Android operating system has been developed for the purpose of recording vibration, noise levels, location and speed data during ambulance journeys. Smartphone accelerometers were calibrated using sinusoidal excitation and the microphones using calibrated pink noise. Four smartphones were provided to the local neonatal transport team and mounted on their neonatal transport systems to collect data. Repeatability of app recordings was assessed by comparing 37 journeys, made during the study period, along an 8.5 km single carriageway. The smartphones were found to have an accelerometer accurate to 5% up to 55 Hz and microphone accurate to 0.8 dB up to 80 dB. Use of the app was readily adopted by the neonatal transport team, recording more than 97,000 km of journeys in 1 year. To enable comparison between journeys, the 8.5 km route was split into 10 m segments. Interquartile ranges for vehicle speed, vertical acceleration and maximum noise level were consistent across all segments (within 0.99 m . s^-1, 0.13 m · s^-2 and 1.4 dB, respectively). Vertical accelerations registered were representative of the road surface. Noise levels correlated with vehicle speed. Android smartphones are a viable method of accurate mass data collection for this application. We now propose to utilise this approach to reduce potential harmful exposure, from vibration and noise, by routing ambulances along the most comfortable roads.

Widefield two laser interferometry

A novel system has been developed that can capture the wide-field interference pattern generated by interfering two independent and incoherent laser sources. The interferograms are captured using a custom CMOS modulated light camera (MLC) which is capable of demodulating light in the megahertz region. Two stabilised HeNe lasers were constructed in order to keep the optical frequency difference (beat frequency) between the beams within the operational range of the camera.This system is based on previously reported work of an ultrastable heterodyne interferometer [Opt. Express 20, 17722 (2012)]. The system used an electronic feedback system to mix down the heterodyne signal captured at each pixel on the camera to cancel out the effects of time varying piston phase changes observed across the array. In this paper, a similar technique is used to track and negate the effects of beat frequency variations across the two laser pattern. This technique makes it possible to capture the full field interferogram caused by interfering two independent lasers even though the beat frequency is effectively random.As a demonstration of the system's widefield interferogram capture capability, an image of a phase shifting object is taken using a very simple two laser interferometer.

Ultrastable heterodyne interferometer system using a CMOS modulated light camera

A novel ultrastable widefield interferometer is presented. This uses a modulated light camera (MLC) to capture and stabilise the interferogram in the widefield heterodyne interferometer. This system eliminates the contribution of piston phase to the interferogram without the need for common path optics and results in a highly stable widefield interferometer. The MLC uses quadrature demodulation circuitry built into each pixel to demodulate the light signal and extract phase information using an electronic reference signal. In contrast to the work previously presented [Opt. Express 19, 24546 (2011)], the reference signal is derived from one of the pixels on board the MLC rather than an external source. This local reference signal tracks the instantaneous modulation frequency detected by the other pixels and eliminates the contribution of piston phase to the interferogram, substantially removing the contributions of unwanted vibrations and microphonics to the interferogram. Interferograms taken using the ultrastable system are presented with one of the interferometer mirrors moving at up to 85 mm s(-1) over a variety of frequencies from 18 Hz to 20 kHz (giving a variation in optical path length of 220 μm, or 350 wavelengths at 62 Hz). This limit was the result of complex motion in the mirror mount rather than the stability limit of the system. The system is shown to be insensitive to pure piston phase variations equivalent to an object velocity of over 3 m s(-1).

Widefield heterodyne interferometry using a custom CMOS modulated light camera

In this paper a method of taking widefield heterodyne interferograms using a prototype modulated light camera is described. This custom CMOS modulated light camera (MLC) uses analogue quadrature demodulation at each pixel to output the phase and amplitude of the modulated light as DC voltages. The heterodyne interference fringe patterns are generated using an acousto-optical frequency shifter (AOFS) in an arm of a Mach-Zehnder interferometer. Widefield images of fringe patterns acquired using the prototype MLC are presented. The phase can be measured to an accuracy of ±6.6°. The added value of this method to acquire widefield images are discussed along with the advantages.

The UCLA longitudinal study of neurocognitive outcomes following mild pediatric traumatic brain injury

Comprehensive reviews of neurocognitive outcomes following mild, uncomplicated traumatic brain injury (TBI) in children have shown minimal effects on neurocognition, especially in methodologically rigorous studies. In this study, we report longitudinal (1, 6, and 12 months post injury) results in four domains of neurocognitive functioning in a large sample of children with mild TBI (n = 124, ages 8-17 at injury) relative to two demographically matched control groups (other injury: n = 94 and non-injury: n = 106). After accounting for age and parental education, significant main effects of group were observed on 7 of the 10 neurocognitive tests. However, these differences were not unique to the TBI sample but were found between both the TBI and other injury groups relative to the non-injured group, suggesting a general injury effect. Effects were primarily within the domains measuring memory, psychomotor processing speed, and language. This is the largest longitudinal study to date of neurocognitive outcomes at discrete time points in pediatric mild TBI. When controlling for pre-injury factors, there is no evidence of long-term neurocognitive impairment in this group relative to another injury control group. The importance of longitudinal analyses and use of appropriate control groups are discussed in the context of evaluating the effects of mild TBI on cognition.

Late Diagnosis of Neurodegenerative Disease in Children: Anosognosia by Proxy

Anosognosia is a term now generally defined as a failure to recognize the existence of disease processes, particularly those with a neurological basis. Denial of illness has been recognized in a large number of disorders, and is generally thought to have not only a central nervous system basis, but to also be influenced by the psychological processes of denial. This disorder has been reported in the adult population, and there are initial suggestions that it exists in children/adolescents. We propose to extend the concept of anosognosia to the caregivers of children who suffer significant dementia, and extended degeneration in neuropsychological and neurological functioning. We term this syndrome anosognosia by proxy. Three case examples are presented in which parents, teachers, and health care professionals observed extended deterioration in a child/adolescent's level of functioning prior to seeking appropriate diagnostic evaluations. Possible explanations for this process are advanced, including a combination of insidious onset coupled with the intimate nature of the child/parent relationship. The need for professional, teacher, and parent education on the nature of childhood degenerative neurological disorders is emphasized.

Factors associated with prolonged mechanical ventilation following coronary artery bypass surgery

STUDY OBJECTIVES

To identify the typical duration of postoperative mechanical ventilation following coronary artery bypass graft surgery (CABG), and to identify risk factors for prolonged postoperative ventilation.

DESIGN

Retrospective study of 4,863 consecutive patients using univariate and multivariate survival analysis to identify independent risk factors.

SETTING

Saint Thomas Hospital, Nashville, TN, a 575-bed, academically affiliated, regional referral hospital specializing in cardiovascular diseases.

PATIENTS

All patients undergoing CABG in our hospital from January 1, 1996, to December 31, 1997.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Duration of mechanical ventilation and mortality were measured. More than 94% of the patients were extubated in the first 3 days following surgery, 4% more were extubated from postoperative days 4 to 14, and almost 2% were receiving ventilation for > 14 days. Those risk factors that reflect preoperative medical instability, especially cardiac or respiratory insufficiency, were associated with the highest incidence of prolonged postoperative mechanical ventilation and for operative mortality. The Society of Thoracic Surgeons-predicted mortality estimate was the best single independent predictor for prolonged postoperative ventilation.

CONCLUSIONS

Typically, patients can be expected to be extubated within 3 days after CABG. Certain preoperative comorbidities, especially preoperative cardiac or respiratory instability, are predictive of prolonged postoperative mechanical ventilation.

Management of spontaneous pneumothorax: an American College of Chest Physicians Delphi consensus statement

OBJECTIVE

Provide explicit expert-based consensus recommendations for the management of adults with primary and secondary spontaneous pneumothoraces in an emergency department and inpatient hospital setting. The use of opinion was made explicit by employing a structured questionnaire, appropriateness scores, and consensus scores with a Delphi technique. The guideline was designed to be relevant to physicians who make management decisions for the care of patients with pneumothorax.

OPTIONS

Decisions for observation, chest tube placement, surgical interventions, and radiographic imaging.

OUTCOMES

Effectiveness of pneumothorax resolution, duration of and patient tolerance of care, and pneumothorax recurrence.

EVIDENCE

Literature review from 1967 to January 1999 and Delphi questionnaire submitted in three iterations to a multidisciplinary physician panel.

VALUES

The guideline development group determined by consensus the relevant outcomes to be considered in developing the Delphi questionnaire.

BENEFITS, HARMS, AND COSTS

The type and magnitude of benefits, harms, and costs expected for patients from guideline implementation.

RECOMMENDATIONS

Management decisions vary between patients with primary or secondary pneumothoraces, with observation of small pneumothoraces being appropriate only for primary pneumothoraces. The level of consensus varies regarding the specific interventions indicated, but agreement exists for the general principles of care.

VALIDATION

Recommendations were peer reviewed by physician experts and were reviewed by the American College of Chest Physicians (ACCP) Health and Science Policy Committee.

IMPLEMENTATION

The guideline recommendations will be published in printed and electronic form with distribution of synopses for patients and health care providers. Contents of the guideline will be incorporated into continuing medical education programs.

SPONSORS

The ACCP.

Medical and surgical treatment of parapneumonic effusions : an evidence-based guideline

OBJECTIVE

A panel was convened by the Health and Science Policy Committee of the American College of Chest Physicians to develop a clinical practice guideline on the medical and surgical treatment of parapneumonic effusions (PPE) using evidence-based methods.

OPTIONS AND OUTCOMES CONSIDERED

Based on consensus of clinical opinion, the expert panel developed an annotated table for evaluating the risk for poor outcome in patients with PPE. Estimates of the risk for poor outcome were based on the clinical judgment that, without adequate drainage of the pleural space, the patient with PPE would be likely to have any or all of the following: prolonged hospitalization, prolonged evidence of systemic toxicity, increased morbidity from any drainage procedure, increased risk for residual ventilatory impairment, increased risk for local spread of the inflammatory reaction, and increased mortality. Three variables, pleural space anatomy, pleural fluid bacteriology, and pleural fluid chemistry, were used in this annotated table to categorize patients into four separate risk levels for poor outcome: categories 1 (very low risk), 2 (low risk), 3 (moderate risk), and 4 (high risk). The panel's consensus opinion supported drainage for patients with moderate (category 3) or high (category 4) risk for a poor outcome, but not for patients with very low (category 1) or low (category 2) risk for a poor outcome. The medical literature was reviewed to evaluate the effectiveness of medical and surgical management approaches for patients with PPE at moderate or high risk for poor outcome. The panel grouped PPE management approaches into six categories: no drainage performed, therapeutic thoracentesis, tube thoracostomy, fibrinolytics, video-assisted thoracoscopic surgery (VATS), and surgery (including thoracotoiny with or without decortication and rib resection). The fibrinolytic approach required tube thoracostomy for administration of drug, and VATS included post-procedure tube thoracostomy. Surgery may have included concomitant lung resection and always included postoperative tube thoracostomy. All management approaches included appropriate treatment of the underlying pneumonia, including systemic antibiotics. Criteria for including articles in the panel review were adequate data provided for >/=20 adult patients with PPE to allow evaluation of at least one relevant outcome (death or need for a second intervention to manage the PPE); reasonable assurance provided that drainage was clinically appropriate (patients receiving drainage were either category 3 or category 4) and drainage procedure was adequately described; and original data were presented. The strength of panel recommendations on management of PPE was based on the following approach: level A, randomized, controlled trials with consistent results or individual randomized, controlled trial with narrow confidence interval (CI); level B, controlled cohort and case control series; level C, historically controlled series and case series; and level D, expert opinion without explicit critical appraisal or based on physiology, bench research, or "first principles."

EVIDENCE

The literature review revealed 24 articles eligible for full review by the panel, 19 of which dealt with the primary management approach to PPE and 5 with a rescue approach after a previous approach had failed. Of the 19 involving the primary management approach to PPE, there were 3 randomized, controlled trials, 2 historically controlled series, and 14 case series. The number of patients included in the randomized controlled trials was small; methodologic weaknesses were found in the 19 articles describing the results of primary management approaches to PPE. The proportion and 95% CI of patients suffering each of the two relevant outcomes (death and need for a second intervention to manage the PPE) were calculated for the pooled data for each management approach from the 19 articles on the primary management approach. (ABST

The utility of daily therapeutic thoracentesis for the treatment of early empyema

STUDY OBJECTIVES

To determine if therapeutic thoracentesis is as effective as early chest tube placement or no drainage procedure in the treatment of early empyema in rabbits.

DESIGN AND INTERVENTIONS

An empyema, as evidenced by gross pleural pus and a decreased pleural fluid pH and glucose level, was induced in 49 rabbits. The rabbits were divided into three groups: 16 underwent daily therapeutic thoracentesis starting at 48 h, 14 underwent chest tube placement at 48 h, and 19 served as controls.

RESULTS

The mortality rate in the therapeutic thoracentesis group (0/16) did not differ significantly from that in the chest tube group (3/14) or that in the control group (6/19). At autopsy at 10 days, the gross empyema score in the therapeutic thoracentesis group (2.1 +/- 0.3) was significantly lower (p < 0.05) than that in the chest tube group (2. 8 +/- 0.3) or the control group (3.5 +/- 0.2). The mean pleural peel score of 5.8 +/- 1.1 in the therapeutic thoracentesis group was significantly less (p < 0.05) than the score for the nonintervention control group (13.4 +/- 1.6).

CONCLUSIONS

From this study, we conclude that therapeutic thoracentesis is at least as effective as early chest tube placement for the treatment of early empyema using our rabbit model of empyema.

Mild closed-head injury in children and adolescents: behavior problems and academic outcomes

The issue of whether mild head injuries (HIs) in children cause behavior problems and poor scholastic performance is controversial. This study included 119 children (range = 8-16 years old) with HI, 114 with other injuries, and 106 with no injury (NI). Behavioral functioning was assessed with the Child Behavior Checklist; academic functioning, with school grades and standardized testing. Higher T scores were found for both injury groups versus NI participants on preinjury behavioral status. All 3 groups' behavioral scores decreased relative to baseline at 1 year. HI and NI groups did not differ in school grades or achievement testing either pre- or postinjury. These results are consistent with the conclusion that head injury of the mildest type does not increase the probability of new overt behavioral or academic problems.

Mild closed-head injury in children and adolescents: behavior problems and academic outcomes

The issue of whether mild head injuries (HIs) in children cause behavior problems and poor scholastic performance is controversial. This study included 119 children (range = 8-16 years old) with HI, 114 with other injuries, and 106 with no injury (NI). Behavioral functioning was assessed with the Child Behavior Checklist; academic functioning, with school grades and standardized testing. Higher T scores were found for both injury groups versus NI participants on preinjury behavioral status. All 3 groups' behavioral scores decreased relative to baseline at 1 year. HI and NI groups did not differ in school grades or achievement testing either pre- or postinjury. These results are consistent with the conclusion that head injury of the mildest type does not increase the probability of new overt behavioral or academic problems.

Depression, cognition, and functional correlates of recovery outcome after traumatic brain injury

The present study investigated the prevalence and magnitude of depressive symptomatology in a sample of patients who had sustained traumatic brain injury (TBI) six months earlier. Depression was examined as a function of recovery outcome status, and its association with neuropsychological functioning, personal competency, and employability was also explored. Subjects were 100 patients who had previously sustained moderate-to-severe TBI who were enrolled as research subjects in the UCLA Brain Injury Research Center, and 30 matched control subjects who had sustained traumatic injuries other than to the head six months prior to evaluation. The results showed a significant association between depression and recovery status as measured by the Glasgow Outcome Scale (GOS). A significant majority of depressed subjects were found in the poorer GOS outcome groups (severe and moderate disability), compared to TBI subjects who had good GOS outcomes, and control subjects. This association was also reflected in the magnitude of the mean depression scores on two self-report measures of depression. However, no association was found between depression status and performance on the neuropsychological measures. Effects of depression were found only on an examiner-rated Patient Competency scale, and a metacognition measure based on self-report. These results are discussed in terms of brain injury severity, recovery status, and metacognition issues in TBI and other disorders.

Neuropsychological, psychosocial and vocational correlates of the Glasgow Outcome Scale at 6 months post-injury: a study of moderate to severe traumatic brain injury patients

Traumatic brain injury (TBI) subjects at Glasgow Outcome Scale levels 3 (severe disability), 4 (moderate disability), 5 (good recovery), and an other-injury control group (OIC) were compared in terms of neuropsychological, psychosocial, and vocational functioning 6 months after injury. Subjects were a sample of 100 patients with a moderate to severe traumatic brain injury (TBI) and a matched sample of 30 other-injury control subjects (OIC) enrolled in the UCLA Brain Injury Research Center study of TBI outcome. Overall, the results showed a systematic decrease in mean neuropsychological test performance as a function of increasing GOS severity, as well as an increased prevalence of symptoms of depression and lower ratings on measures assessing employability and capacity for self care. TBI patients in the 'severe' and 'moderate disability' groups were distinctly inferior to the 'good recovery' and 'OIC' groups, who were quite similar to each other in terms of cognitive, psychosocial, and vocational outcomes. The results demonstrate overall support for the predictive and concurrent validity of the GOS 6 months post injury. Despite these results, which strengthen the utility and appeal of the GOS for multicentre studies, concerns still remain regarding GOS category 4 (moderate disability), which was shown to lack sufficient discriminability in this study.

Axillary artery injury as a complication of proximal humerus fractures

Proximal humerus fractures are common injuries and represent approximately 5% of all fractures. These fractures are infrequently associated with neurovascular injuries. Brachial plexus injuries are uncommon, whereas axillary artery injuries are rare. A review of 19 previously reported cases of axillary artery injury after proximal humerus fracture revealed that 84% occurred in patients older than 50 years, 53% were associated with brachial plexus injury, and 21% resulted in upper extremity amputation. This study describes a case of axillary artery injury after proximal humerus fracture and, on the basis of a literature review, offers suggestions for the early diagnosis and effective treatment of this uncommon injury.

Depression after traumatic brain injury as a function of Glasgow Outcome Score

One hundred and five patients with traumatic brain injury (TBI) were assessed for depressive symptomatology at 6 months postinjury and 66 of those patients were examined again at 12 months postinjury. At 6 months, 42% of the patients with TBI and 20% of the Other Injury Control Group (OIC) were identified as depressed. Individuals with poor outcome (as measured by Glasgow Outcome Score [GOS]) had a higher frequency of depressive symptomatology than those with good GOS outcome. At 12 months, 36% of the patients with TBI and 28% of the OIC group were identified as depressed. At 12 months, there was no difference in terms of frequency of depressive symptomatology among patients with TBI with poor, moderate, or good outcome.

Mild head injury in children and adolescents: a review of studies (1970-1995)

In this article, the authors provide a comprehensive review of the research of mild head injury in children and adolescents from 1970 to 1995. Because of marked variability in methodologies across studies, a preliminary box-score tally was computed, without regard to studies' scientific or methodological merit. These results revealed 13 adverse, 18 null, and 9 indeterminate findings related to neuropsychological, academic, or psychosocial outcome. When studies were classified based on methodological merit, the stronger studies were generally associated with null outcomes across domains. However, a few of the less stronger neuropsychological studies (5 of 40) reported subthreshold and transitory alterations during the early postinjury period. At the present time, cautious acceptance of the null hypothesis is recommended until more definitive studies are conducted that address the problems raised in this review.

Mild head injury in children and adolescents: a review of studies (1970-1995)

In this article, the authors provide a comprehensive review of the research of mild head injury in children and adolescents from 1970 to 1995. Because of marked variability in methodologies across studies, a preliminary box-score tally was computed, without regard to studies' scientific or methodological merit. These results revealed 13 adverse, 18 null, and 9 indeterminate findings related to neuropsychological, academic, or psychosocial outcome. When studies were classified based on methodological merit, the stronger studies were generally associated with null outcomes across domains. However, a few of the less stronger neuropsychological studies (5 of 40) reported subthreshold and transitory alterations during the early postinjury period. At the present time, cautious acceptance of the null hypothesis is recommended until more definitive studies are conducted that address the problems raised in this review.

Visuospatial learning: Ruff Light Trail Learning Test

The assessment of memory typically includes tests for both audioverbal and visuospatial processing, while measurements of learning have primarily utilized the audioverbal mode. However, there exists no compelling reason why learning should not also be assessed in the visuospatial mode. The Ruff Light Trail Learning Test (RULIT) represents such an option. Normative values utilizing 307 volunteers indicated neither significant gender nor educational differences. However, an age effect for those subjects 55 and older was demonstrated, and our data suggest that the major reason for the inferior learning in this older subgroup was their reduced memory capacities rather than their slowed visuospatial processing. Multiple components including learning curves, error analysis, and delayed recall are presented. Test-retest data also indicate an adequate reliability. The validity was compared to concurrently administered neuropsychological tests, and, finally, the potential for neuropsychological application of this new test is discussed.

Children's color trails

Color Trails for Children was developed in response to the need for instruments which minimize cultural bias in neuropsychological testing. The test, similar in format to Trail Making, was designed to provide an evaluation of speeded visuomotor tracking while minimizing the influence of language. The present research involves two exploratory studies which examine the relationship between Color Trails for Children and Trail Making, factors that may affect performance times, and discriminant validity. Results indicate that the tests appear to measure the same neuropsychological domains, and administration of Trail Making did not significantly alter performance times on Color Trails. Increasing age and IQ were related to quicker completion time for both tests. Females were found to complete Color Trails 2 and Trail Making Part B more quickly than males in this sample. Comparison between children diagnosed with learning disabilities, attention deficits, or mild neurological conditions and a preliminary standardization sample supported the discriminant validity of Color Traits to distinguish between normal controls and children with altered neuropsychological functioning. Comparison between clinical conditions indicated that Color Trails 2 was particularly sensitive in discriminating among the groups. Although further research is needed, results suggest that Color Trails has the potential to be an effective research and clinical tool in child neuropsychological assessment.

Behavior problems and adaptive functioning in children with mild and severe closed head injury

Assessed behavior problems and adaptive functioning in children with mild or severe closed head injuries, on average more than 2 years postaccident. To ensure that any problems detected in the present study were not merely preexisting problems, potential subjects were excluded if there was a history of preexisting CNS damage, significant developmental delay, or behavior problems. Children with severe head injuries had an excessive rate of behavior problems and impaired adaptive functioning. Children with mild head injuries also had an excessive rate of behavior problems (comparable to that of children with severe head injuries) but did not have impaired adaptive functioning. Results are discussed in terms of six alternative ways brain injury and behavior problems can be related functionally.

Dietary fluoride supplements for Tennessee's children: the role of the physician

1. All children should receive some form of systemic fluoride and appropriate forms of topical fluoride. 2. If a child is not receiving optimally fluoridated water, the physician or dentist should prescribe a dietary fluoride supplement as tablets or drops. 3. The correct dosage must be determined, based on patient age and fluoride content of the patient's drinking water. 4. Special attention is necessary concerning fluoride intake for children breast-feeding or consuming infant formula. 5. To arrive at the correct fluoride dose, these steps should be followed: (A) Whenever you do not have specific knowledge of water fluoride content, have a sample of the main drinking water source (usually home water) analyzed for the fluoride content before prescribing a fluoride supplement. (B) When the fluoride content of the water has been determined, the fluoride level and the child's age should be matched on Table 1 to arrive at the correct supplement dose. 6. The Fluoridation Program of the Tennessee Division of Water Supply can provide lists of communities and schools in Tennessee that are optimally fluoridated.

Null hypothesis disrespect in neuropsychology: dangers of alpha and beta errors

To understand why there are so many inconsistencies and contradictory findings among hemispheric-asymmetry studies, data were analyzed from a large study of 300 left-handers. These data included information on familial sinistrality (FS), handwriting posture (HPO), a measure of cognitive performance, and five measures of hemispheric specialization. Using computer simulation methodology, 40 independent samples of 36 to 65 subjects each were drawn randomly with replacement. The sample data were analyzed and the results compared to those of the parent "population." Often, the samples poorly reflected the parent "population," and some procedures substantially inflated error rates. These procedures are discussed and specific guidelines suggested. These results are also discussed in the broader context of the necessity for investigators in neuropsychology to differentiate between the statistical and clinical significance of research findings; and to develop a more positive attitude toward the design, execution, and publication of replication studies.