Variability in expert assessments of child physical abuse likelihood

OBJECTIVES

In the absence of a gold standard, clinicians and researchers often categorize their opinions of the likelihood of inflicted injury using several ordinal scales. The objective of this protocol was to determine the reliability of expert ratings using several of these scales.

METHODS

Participants were pediatricians with substantial academic and clinical activity in the evaluation of children with concerns for physical abuse. The facts from several cases that were referred to 1 hospital's child abuse team were abstracted and recorded as in a multidisciplinary team conference. Participants viewed the recording and rated each case using several scales of child abuse likelihood.

RESULTS

Participants (n = 22) showed broad variability for most cases on all scales. Variability was lowest for cases with the highest aggregate concern for abuse. One scale that included examples of cases fitting each category and standard reporting language to summarize results showed a modest (18%-23%) decrease in variability among participants. The interpretation of the categories used by the scales was more consistent. Cases were rarely rated as "definite abuse" when likelihood was estimated at < or = 95%. Only 7 of 156 cases rated < or = 15% likelihood were rated as "no reasonable concern for abuse." Only 9 of 858 cases rated > or = 35% likelihood were rated as "reasonable concern for abuse."

CONCLUSIONS

Assessments of child abuse likelihood often show broad variability between experts. Although a rating scale with patient examples and standard reporting language may decrease variability, clinicians and researchers should be cautious when interpreting abuse likelihood assessments from a single expert. These data support the peer-review or multidisciplinary team approach to child abuse assessments.

Acute vascular responses to the frequency of vibration transmitted to the hand

OBJECTIVES

To investigate the acute effects of the frequency of hand transmitted vibration on finger circulation. A further aim was to investigate whether the frequency weighting assumed in current standards for hand transmitted vibration reflects the haemodynamic changes which occur in the fingers exposed to vibration with different frequencies but with the same frequency weighted acceleration magnitude.

METHODS

Finger skin temperature (FST) and finger blood flow (FBF) were measured in the middle fingers of both hands of 10 healthy men. With a static load of 10 N, the right hand was exposed for 15 minutes to the following root mean square (rms) acceleration magnitudes and frequencies of vertical vibration: 5.5 m/s(2) at 16 Hz; 11 m/s(2) at 31.5 Hz; 22 m/s(2) at 63 Hz; 44 m/s(2) at 125 Hz; and 88 m/s(2) at 250 Hz. These exposures to vibration produce the same frequency weighted acceleration magnitude (5.5 m/s(2) rms) according to the frequency weighting included in the international standard ISO 5349. A control condition consisted of exposure to the static load only. Finger circulation was measured before application of the vibration and static load and at fixed intervals during exposure to vibration and a 45 minute recovery period.

RESULTS

No significant changes in finger circulation were found with only the static load. The FST did not change significantly during or after acute exposure to vibration. In the vibrated right finger, exposures to vibration with frequencies of 31. 5-250 Hz provoked a greater reduction in FBF than did vibration of 16 Hz or the static load only. In the non-vibrated left finger, the FBF measured with vibration at each frequency of 63-250 Hz was significantly lower than that measured with static load only. The reduction in FBF during exposure to vibration with any frequency was stronger in the vibrated finger than in the non-vibrated finger. In both fingers, there was a progressive decrease in FBF after the end of exposure to vibration with frequencies of 31.5-250 Hz. The higher the frequency of vibration, the stronger the decrease in FBF in both fingers during recovery.

CONCLUSIONS

Acute exposures to vibration with equal frequency weighted magnitude reduce the FBF in both vibrated and non-vibrated fingers for frequencies between 31.5 and 250 Hz. The extent of digital vasoconstriction after exposure to vibration increases with increasing frequency. The frequency weighting given in current standards tends to overestimate the vasoconstriction associated with acute exposures to vibration frequencies around 16 Hz.

Magnitude of acute exposures to vibration and finger circulation

OBJECTIVES

Changes in finger circulation were studied during and after acute exposure to increasing magnitudes of hand-transmitted vibration.

METHODS

Finger skin temperature (FST) and finger blood flow (FBF) were measured in the middle fingers of both hands of 10 healthy men. The right hand was exposed for 15 minutes to 125-Hz vibration with acceleration magnitudes of either 5.5, 22, 44, or 62 m/s2 root-mean-square. The measures of finger circulation were taken before the vibration, at fixed intervals during exposure, and during a 45-minute recovery period.

RESULTS

The FST did not change during vibration exposure, whereas vibration of any magnitude provoked significant reductions in the FBF of the vibrated finger when compared with the preexposure FBF and the contralateral (nonvibrated finger) FBF. Vasoconstrictor aftereffects (i.e., during recovery) were observed in both fingers after the end of exposure to vibration magnitudes greater than 22 m/s2 root-mean-square. The higher the vibration magnitude, the stronger the reduction of FBF in either finger during both vibration exposure and the recovery period. This effect was stronger in the vibrated finger than in the nonvibrated finger during both periods.

CONCLUSIONS

Acute exposure to 125-Hz vibration can reduce FBF in both the vibrated and the nonvibrated finger, and the degree of digital vasoconstriction is related to the magnitude of the vibration. The pattern of the hemodynamic changes during and after vibration exposure suggests that complex vasomotor mechanisms are involved in the response of digital vessels to acute vibration.

Duration of acute exposures to vibration and finger circulation

OBJECTIVES

This study investigated changes in finger circulation after different durations of exposure to hand-transmitted vibration.

METHODS

Finger skin temperature (FST), finger blood flow (FBF), and finger systolic blood pressure (FSBP) were measured in the middle fingers of both hands of 10 healthy men. Finger vascular resistance was also estimated. The right hand was exposed for 7.5, 15, and 30 minutes (static load 10 N) to 125-Hz vibration (root-mean-square acceleration 87 m/s2). Static load only was used as a control. Finger circulation was measured before the vibration and static load exposure and at fixed intervals during exposure and a 45-minute recovery period.

RESULTS

No significant changes were found with the static load. The FST and FSBP did not change significantly during vibration exposure, whereas vibration produced significant reductions in FBF and increases in vascular resistance at each duration when compared with preexposure and contralateral (non-vibrated) finger values. Temporary vasodilation occurred in the vibrated finger immediately after each vibration exposure. Recovery was complete for FBF and vascular resistance after the 7.5-minute vibration, whereas a progressive FBF reduction occurred in both the vibrated and the nonvibrated fingers after 15- and 30-minute exposure. The longer the duration of vibration exposure, the stronger the vasoconstriction in the vibrated finger during recovery.

CONCLUSIONS

Vasoregulatory mechanisms mediated by both intrinsic (local) and extrinsic (neural or endocrine) control systems seem to be related to digital circulatory changes during 125-Hz vibration. It is concluded that, not only the frequency and magnitude of vibration, but also its duration contributes to the reaction of the digital vessels to acute vibration.

Response of finger circulation to energy equivalent combinations of magnitude and duration of vibration

OBJECTIVES

To investigate the acute response of finger circulation to vibration with different combinations of magnitude and duration but with the same "energy equivalent" acceleration magnitude according to current standards for hand transmitted vibration.

METHODS

Finger skin temperature (FST) and finger blood flow (FBF) were measured in the middle fingers of both hands of 10 healthy men who had not used hand held vibrating tools regularly. With a static load of 10 N, the right hand was exposed to 125 Hz vibration with the following unweighted root mean square (rms) acceleration magnitudes and durations of exposure: 44 m/s(2) for 30 minutes; 62 m/s(2) for 15 minutes; 88 m/s(2) for 7.5 minutes; 125 m/s(2) for 3.75 minutes; and 176 m/s(2) for 1.88 minutes. These vibration exposures produce the same 8 hour energy equivalent frequency weighted acceleration magnitude (approximately 1.4 m/s(2) rms) according to international standard ISO 5349 (1986). Finger circulation was measured in both the right (vibrated) and the left (non-vibrated) middle fingers before application of the vibration, and at fixed intervals during exposure to vibration and during a 45 minute recovery period.

RESULTS

The FST did not change during exposure to vibration, whereas vibration with any combination of acceleration magnitude and duration produced significant percentage reductions in the FBF of the vibrated finger compared with the FBF before exposure (from -40.1% (95% confidence interval (95% CI) -24.3% to -57.2%) to -61.4% (95% CI -45.0% to -77.8%). The reduction in FBF during vibration was stronger in the vibrated finger than in the non-vibrated finger. Across the five experimental conditions, the various vibration stimuli caused a similar degree of vasoconstriction in the vibrated finger during exposure to vibration. There was a progressive decrease in the FBF of both fingers after the end of exposure to vibration with acceleration magnitudes of 44 m/s(2) for 30 minutes and 62 m/s(2) for 15 minutes. Significant vasoconstrictor after effects were not found in either finger after exposure to any of the other vibration stimuli with greater acceleration magnitudes for shorter durations.

CONCLUSIONS

For the range of vibration magnitudes investigated (44 to 176 m/s(2) rms unweighted; 5.5 to 22 m/s(2) rms when frequency weighted according to ISO 5349), the vasoconstriction during exposure to 125 Hz vibration was independent of vibration magnitude. The after effect of vibration was different for stimuli with the same energy equivalent acceleration, with greater effects after longer durations of exposure. The energy equivalent acceleration therefore failed to predict the acute effects of vibration both during and after exposure to vibration. Both central and local vasoregulatory mechanisms are likely to be involved in the response of finger circulation to acute exposures to 125 Hz vibration.

Thermal thresholds, vibrotactile thresholds and finger systolic blood pressures in dockyard workers exposed to hand-transmitted vibration

OBJECTIVES

To quantify neurological dysfunction in workers exposed to hand-transmitted vibration using alternative neurological tests. To relate the neurological findings to the results of vascular tests and the symptoms reported by subjects with vibration-induced white finger.

METHODS

Thermal thresholds (for perception of heat and cold), vibrotactile thresholds (for perception of vibration at 31.5 and 125 Hz) and finger systolic blood pressures were measured in 107 dockyard workers, including 31 controls and 76 workers exposed to hand-transmitted vibration (50 reporting finger blanching consistent with vibration-induced white finger). A history of vibration exposure and symptoms associated with hand-transmitted vibration were obtained for each subject.

RESULTS

Increased duration of exposure to vibration resulted in a deterioration of both thermal thresholds and vibrotactile thresholds. Finger systolic blood pressures were lower in subjects reporting finger blanching and were related to the extent of blanching on the measured finger. Reported sensations of tingling were not correlated with any of the threshold measures; thermal thresholds and vibrotactile thresholds showed evidence of deterioration with reports of increasing numbness. Both numbness and tingling were correlated with reports of finger blanching. Finger systolic blood pressures were not correlated with either thermal or vibrotactile thresholds.

CONCLUSIONS

Vascular and neurological signs produced by hand-transmitted vibration can occur independently, but the principal vascular symptom (i.e. attacks of blanching) and some commonly reported neurological symptoms (i.e. sensations of numbness and tingling) may be related.

Interpretation of the finger skin temperature response to cold provocation

OBJECTIVES

To compare alternative methods of interpreting the response of finger skin temperature (FST) to cold provocation for the detection of the abnormal cold response observed in vibration-induced white finger (VWF).

METHOD

The FST response to cold provocation was measured in 36 male subjects: 12 office workers, 12 manual workers and 12 manual workers with symptoms of VWF. The FSTs were monitored continuously on the distal phalanges of all five fingers of a test hand for 2 min before, for 5 min during, and for 10 min following, immersion of the test hand in water at 15 degrees C. Of the fingers investigated, 147 were reported not to exhibit blanching and 33 were reported to exhibit blanching. Twenty-one alternative methods of interpreting the response of FSTs to cold provocation were assessed. These were grouped as: (1) areas above the response profile (i.e. the area above the curve showing the FSTs as a function of time during cooling and recovery), (2) areas below the response profile, (3) absolute temperatures during and following cold provocation, (4) percentage differences in FSTs, (5) the times taken for FSTs to rise by specified amounts and (6) rates of change of FSTs. Differences in the response to cooling between those fingers reported to blanch and the fingers not reported to blanch were tested, and receiver operating characteristics (ROCs) were used to compare the sensitivity and specificity of the various measures to symptoms of VWF.

RESULTS

The areas above the response profile, areas below the response profile, percentage FSTs, absolute FSTs and rates of change of FSTs tended to discriminate between healthy and unhealthy subjects on a group basis. However, some of these methods of interpreting the FST response to cold provocation did not show a high sensitivity or specificity to vascular dysfunction on individual fingers. The area above the response profile, the percentage of initial temperature at the fifth minute of recovery and the maximum temperature during the 10-min recovery period, were found to show the highest sensitivity and specificity to symptoms of vascular dysfunction.

CONCLUSIONS

The method chosen to interpret the FST response to cold provocation affects the ability of the test to detect an abnormal cold response. The area above the response profile, the percentage of initial temperature at the fifth minute of recovery and the maximum temperature achieved during a 10-min recovery period appear to be the most suitable measures for monitoring vascular function in workers exposed to hand-transmitted vibration. It is suggested that the FST response to cold provocation should be interpreted with respect to the state of initial blood flow.

Initial risk stratification and presenting characteristics of patients with evolving myocardial infarctions

OBJECTIVES

To describe the presenting characteristics and risk stratification of patients presenting to the emergency department with chest pain who have a normal initial troponin level followed by a raised troponin level within 12 h (evolving myocardial infarction (EMI)).

METHODS

Data from the Internet Tracking Registry for Acute Coronary Syndromes (i*trACS), a registry of patients presenting with undifferentiated chest pain, were used. This analysis included patients without ST segment elevation with at least two troponin assay results < or = 12 h apart. Patients were stratified into three groups: EMI (initial troponin assay negative, second troponin assay positive), non-ST elevation myocardial infarction (NSTEMI) (initial troponin assay positive) and no MI (all troponin assays negative).

RESULTS

Of 4136 eligible patients, 5% had EMI, 8% had NSTEMI and 87% had no MI. Patients with EMI were more similar to those with NSTEMI than those with no MI with respect to demographic characteristics, presentation, admission patterns and revascularisation. The initial ECG in patients with EMI was most commonly non-diagnostic (51%), but physicians' initial impressions commonly reflected MI, unstable angina or high-risk chest pain (76%). This risk assessment was followed by a high rate of critical care admissions (32%) and revascularisation (percutaneous coronary intervention 17%) among patients with EMI.

CONCLUSION

Patients with EMI appear similar at presentation to those with NSTEMI. Patients with EMI are perceived as being at high risk, evidenced by similar diagnostic impressions, admission practices and revascularisation rates to patients with NSTEMI.

BOugie or stylet in patients UnderGoing Intubation Emergently (BOUGIE): protocol and statistical analysis plan for a randomised clinical trial

INTRODUCTION

Intubation-related complications are less frequent when intubation is successful on the first attempt. The rate of first attempt success in the emergency department (ED) and intensive care unit (ICU) is typically less than 90%. The bougie, a semirigid introducer that can be placed into the trachea to facilitate a Seldinger-like technique of tracheal intubation and is typically reserved for difficult or failed intubations, might improve first attempt success. Evidence supporting its use, however, is from a single academic ED with frequent bougie use. Validation of these findings is needed before widespread implementation.

METHODS AND ANALYSIS

The BOugie or stylet in patients Undergoing Intubation Emergently trial is a prospective, multicentre, non-blinded randomised trial being conducted in six EDs and six ICUs in the USA. The trial plans to enrol 1106 critically ill adults undergoing orotracheal intubation. Eligible patients are randomised 1:1 for the use of a bougie or use of an endotracheal tube with stylet for the first intubation attempt. The primary outcome is successful intubation on the first attempt. The secondary outcome is severe hypoxaemia, defined as an oxygen saturation less than 80% between induction until 2 min after completion of intubation. Enrolment began on 29 April 2019 and is expected to be completed in 2021.

ETHICS AND DISSEMINATION

The trial protocol was approved with waiver of informed consent by the Central Institutional Review Board at Vanderbilt University Medical Center or the local institutional review board at an enrolling site. The results will be submitted for publication in a peer-reviewed journal and presented at scientific conferences.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT03928925).

Cold provocation testing and hand-arm vibration syndrome--an audit of the results of the Department of Trade and Industry for the evaluation of miners (Br J Surg 2003; 90: 1076-1079)

The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses can be sent electronically via the BJS website (www.bjs.co.uk) or by post. All letters will be reviewed and, if approved, appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length. Letters submitted by post should be typed on A4-sized paper in double spacing and should be accompanied by a disk.

Protocol and statistical analysis plan for the PREventing cardiovascular collaPse with Administration of fluid REsuscitation during Induction and Intubation (PREPARE II) randomised clinical trial

INTRODUCTION

Cardiovascular collapse is a common complication during tracheal intubation of critically ill adults. Whether administration of an intravenous fluid bolus prevents cardiovascular collapse during tracheal intubation remains uncertain. A prior randomised trial found fluid bolus administration to be ineffective overall but suggested potential benefit for patients receiving positive pressure ventilation during tracheal intubation.

METHODS AND ANALYSIS

The PREventing cardiovascular collaPse with Administration of fluid REsuscitation during Induction and Intubation (PREPARE II) trial is a prospective, multi-centre, non-blinded randomised trial being conducted in 13 academic intensive care units in the USA. The trial will randomise 1065 critically ill adults undergoing tracheal intubation with planned use of positive pressure ventilation (non-invasive ventilation or bag-mask ventilation) between induction and laryngoscopy to receive 500 mL of intravenous crystalloid or no intravenous fluid bolus. The primary outcome is cardiovascular collapse, defined as any of: systolic blood pressure <65 mm Hg, new or increased vasopressor administration between induction and 2 min after intubation, or cardiac arrest or death between induction and 1 hour after intubation. The primary analysis will be an unadjusted, intention-to-treat comparison of the primary outcome between patients randomised to fluid bolus administration and patients randomised to no fluid bolus administration using a χ² test. The sole secondary outcome is 28-day in-hospital mortality. Enrolment began on 1 February 2019 and is expected to conclude in June 2020.

ETHICS AND DISSEMINATION

The trial was approved by either the central institutional review board at Vanderbilt University Medical Center or the local institutional review board at each trial site. Results will be submitted for publication in a peer-reviewed journal and presented at scientific conferences.

TRIAL REGISTRATION NUMBER

NCT03787732.

Trends in use of composite endpoints in clinical trials: A comparison between acute heart failure trials and COVID-19 trials

Composite endpoints can encode multiple pieces of information and are increasingly adopted in clinical trials. Advocacy for using composite endpoints began decades ago in cardiovascular trials, leading to incorporation of patient-oriented outcomes and consideration of a hierarchical ranking system. The use of composite endpoints in coronavirus disease (COVID-19) trials has evolved similarly. We conducted a literature review to investigate the use of composite endpoints in acute heart failure and COVID-19 clinical trials. The results showed more frequent use of patient-oriented outcomes and ordinal composite endpoints in COVID-19 trials, which might be driven by global consensus on a set of common outcome measures.

Finger systolic blood pressures: effects of cold provocation on the reference finger

Finger systolic blood pressure measured after cold provocation and ischemia of a digit is used to assist in the diagnosis of vibration-induced white finger, VWF. A reduction in finger systolic blood pressure after cooling is assumed to indicate vascular dysfunction. The percentage pressure change observed in the tested finger is often corrected for whole body effects (systemic systolic pressure changes) according to the pressure change measured in a reference finger. The commonly used method of correction is based on assumptions as to the causes of any changes occurring in the reference finger. It is assumed that the reference finger is not differentially susceptible to the cold provocation of the test finger, arising from either close proximity to the cold provocation or from a vascular disorder in the reference finger. An experiment has been undertaken to investigate the repeatability, over three days, of measurements of the arm systolic pressures of both arms and the finger systolic pressures in air of four fingers of both hands. The systolic pressures of both arms and of four fingers of one hand were also measured whilst the fifth finger of the same hand was subjected to cold provocation at 10 degrees C. Twelve healthy male subjects were rested in a supine position for 15 minutes in a room at 21-24 degrees C before measurements were taken. Finger systolic blood pressures were recorded using strain gauge plethysmography. The results show that the systolic blood pressure measurements were generally repeatable, but differed with measurement location. Cold provocation of the test finger had little consistent effect on the systolic pressures measured at other locations. The results are interpreted with regard to the correction of finger systolic pressure using a reference measurement.