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William R Mower

Publications and source records attributed to William R Mower.

At least 19 recordsLinked to original sources
PubMed2007

Evaluation of a modified prediction instrument to identify significant pediatric intracranial injury after blunt head trauma.

STUDY OBJECTIVE: We evaluate the effect of a modification of the University of California-Davis Pediatric Head Injury Rule on the ability of the decision instrument for pediatric head injury to predict clinically important intracranial injury in an external cohort. METHODS: We analyzed data prospectively recorded in 1,666 pediatric patients enrolled in the derivation set of the National Emergency X-Radiography Utilization Study II (NEXUS II). Treating physicians at 21 emergency departments recorded the presence or absence of clinical predictors on all patients who received a head computed tomography (CT) scan after experiencing blunt head trauma. Predictors included 3 exact elements of the University of California-Davis Rule (abnormal mental status, signs of skull fracture, and scalp hematoma in children < or = 2 years of age), some with different wording, and 2 modified elements with new definitions (the presence of high-risk vomiting or severe headache, rather than any vomiting or headache). RESULTS: A significant intracranial injury was identified by CT in 138 (8.3%) patients. Sensitivity of the modified instrument to detect significant intracranial injury was 90.4% (95% confidence interval [CI] 85.4% to 95.4%); 13 children with such an injury were misclassified as low risk. Specificity of the modified instrument was 42.7% (95% CI 40.1% to 45.3%). CONCLUSION: In the NEXUS II cohort, a modified version of the University of California-Davis Rule misclassified a substantial proportion of pediatric patients with clinically important blunt head injury. Although we cannot evaluate the exact University of California-Davis Rule, we demonstrate that using stricter definitions of "headache" and "vomiting" and different wording than in the original study may have unintended or negative consequences. We emphasize the importance of careful attention to precise definitions of clinical predictors when a decision instrument is used.

Adolescent↗
PubMed2007

External validation of the San Francisco Syncope Rule.

STUDY OBJECTIVE: We externally validate the ability of the San Francisco Syncope Rule to accurately identify syncope patients who will experience a 7-day serious clinical event. METHODS: Patients who presented to a single academic emergency department (ED) between 8 am and 10 pm with syncope or near-syncope were prospectively enrolled. Treating physicians recorded the presence or absence of all San Francisco Syncope Rule risk factors. Patients were contacted by telephone at 14 days for a structured interview. A 3-physician panel, blinded to the San Francisco Syncope Rule score, reviewed ED medical records, hospital records, and telephone interview forms to identify predefined serious clinical events. The primary outcome was the ability of the San Francisco Syncope Rule to predict any 7-day serious clinical event. A secondary outcome was the ability of the San Francisco Syncope Rule to predict 7-day serious clinical events that were not identified during the initial ED evaluation. RESULTS: Of 592 eligible patients, 477 (81%) provided informed consent. Direct telephone contact or admission/outpatient records were successfully obtained for 463 (97%) patients. There were 56 (12%) patients who had a serious 7-day clinical event, including 16 (3%) who received a diagnosis after the initial ED evaluation. Sensitivity and specificity of the San Francisco Syncope Rule for the primary outcome were 89% (95% confidence interval [CI] 81% to 97%) and 42% (95% CI 37% to 48%), respectively, and 69% (95% CI 46% to 92%) and 42% (95% CI 37% to 48%), respectively, for the secondary outcome. Estimates of sensitivity were minimally affected by missing data and most optimistic assumptions for missing follow-up information. CONCLUSION: In this external validation cohort, the San Francisco Syncope Rule had a lower sensitivity and specificity than in previous reports.

Adult↗
PubMed2006

Effect of intoxication among blunt trauma patients selected for head computed tomography scanning.

STUDY OBJECTIVE: We examine the prevalence and types of intracranial injuries sustained by intoxicated blunt trauma patients. METHODS: The study was conducted as a secondary analysis of National Emergency X-Radiography Utilization Study II head injury database. Treating physicians prospectively assessed presenting signs and symptoms on all blunt trauma patients who underwent head computed tomography (CT). Intoxication status was determined by the examining physician and was based on a history of intoxication, positive toxicologic screen result, or physical evidence suggesting intoxication. Intracranial injury diagnoses were based on final CT interpretations provided by attending radiologists. RESULTS: Intracranial injury was detected in 1,193 of the 13,728 enrolled patients (8.7%), and intoxication was evident in 3,356 (24.4%) patients. Physicians were unable to assess intoxication status in 620 individuals. Intracranial injury was present in 231 intoxicated patients (231/3,356; 6.9%; 95% confidence interval [CI] 6.0 to 7.8), 789 of 9,752 nonintoxicated patients (8.1%; 95% CI 7.6% to 8.6%), and 173 of the 620 patients who could not be assessed for intoxication (prevalence 27.9%; 95% CI 24.4% to 31.6%). Intracranial injury was identified in only 5 of 299 intoxicated patients (1.7%) who had normal neurological examination results and no evidence of trauma to the calvarium. CONCLUSION: The prevalence of intracranial injury among intoxicated blunt trauma patients who are selected for head CT is lower than among nonintoxicated patients selected for imaging, which likely represents heightened concern in the presence of intoxication, even without other findings suggestive of intracranial injury. This conclusion is supported by the fact that few intoxicated patients with normal neurologic findings and no evidence of trauma to the calvarium had positive findings on CT imaging.

Adult↗
PubMed2006

Performance of a decision rule to predict need for computed tomography among children with blunt head trauma.

OBJECTIVE: To assess the ability of the NEXUS II head trauma decision instrument to identify patients with clinically important intracranial injury (ICI) from among children with blunt head trauma. METHODS: An analysis was conducted of the pediatric cohort involved in the derivation set of National Emergency X-Radiography Utilization Study II (NEXUS II), a prospective, observational, multicenter study of all patients who had blunt head trauma and underwent cranial computed tomography (CT) imaging at 1 of 21 emergency departments. We determined the test performance characteristics of the 8-variable NEXUS II decision instrument, derived from the entire NEXUS II cohort, in the pediatric cohort (0-18 years of age), as well as in the very young children (<3 years). Clinically important ICI was defined as ICI that required neurosurgical intervention (craniotomy, intracranial pressure monitoring, or mechanical ventilation) or was likely to be associated with significant long-term neurologic impairment. RESULTS: NEXUS II enrolled 1666 children, 138 (8.3%) of whom had clinically important ICI. The decision instrument correctly identified 136 of the 138 cases and classified 230 as low risk. A total of 309 children were younger than 3 years, among whom 25 had ICI. The decision instrument identified all 25 cases of clinically important ICI in this subgroup. CONCLUSIONS: The decision instrument derived in the large NEXUS II cohort performed with similarly high sensitivity among the subgroup of children who were included in this study. Clinically important ICI were rare in children who did not exhibit at least 1 of the NEXUS II risk criteria.

Adolescent↗
PubMed2006

Epidemiology of blunt head injury victims undergoing ED cranial computed tomographic scanning.

STUDY OBJECTIVE: We sought to describe the epidemiology of emergency department (ED) patients with blunt head injury undergoing cranial computed tomography (CT) scanning for the evaluation of possible traumatic brain injury (TBI). METHODS: Prospective, multicenter, observational study of ED patients undergoing cranial CT after blunt head injury. Patient's date of birth, sex, and race/ethnicity were documented before CT scanning. Individual patients were considered to have "significant" TBI if the official radiographic interpretation at the end of all imaging studies associated with the trauma was consistent with any of a set of predefined diagnoses. The relative prevalence of TBI among various prespecified groups from those undergoing cranial CT scanning was also calculated. RESULTS: Of 13728 patients who were enrolled, 8988 (65%) were men and 1193 (8.7%) had a significant acute TBI. Demographic findings associated with increased risk of TBI, among patients selected for scanning, included the following: age below 10 years (relative risk [RR] = 1.44, 95% confidence interval [CI], 1.19-1.77); age above 65 years (RR = 1.59; 95% CI, 1.40-1.80), and male sex (RR = 1.27; 95% CI, 1.30-1.43). CONCLUSION: Among patients selected for cranial CT scanning after blunt head injury, men, patients younger than 10 years, and those older than 65 years have an increased likelihood of significant TBI.

Adolescent↗
PubMed2006

Prevalence and prognosis of traumatic intraventricular hemorrhage in patients with blunt head trauma.

BACKGROUND: Most studies of traumatic intraventricular hemorrhage (tIVH) contain fewer than 25 subjects and are retrospective in design, providing minimal information about the entity and its clinical significance. METHODS: We prospectively enrolled trauma patients from 18 centers in North America in the National Emergency X-Radiography Utilization Study (NEXUS) II if they received an emergent head computed tomography (CT) scan, as determined by the managing physician. Clinical data were collected at the time of enrollment and CT reports were compiled at least 1 month later. We calculated prevalence and demographics of tIVH from the 18 sites, while outcome data were gathered from medical records of patients with tIVH who were seen at any of six sites that participated in the follow-up portion of the study. We considered patients who underwent a neurosurgical intervention or who had a "poor outcome" (Glasgow Outcome Scale score of 1 to 3, death, persistent vegetative state, or severe disability) to have suffered a "combined outcome." RESULTS: Prevalence of tIVH among all trauma patients who received a head CT was 118 in 8,374, or 1.41%. Among tIVH patients, 70% had a "poor outcome" and 76% had a "combined outcome." A poor outcome appeared to be associated with an abnormal presenting Glasgow Coma Scale score and involvement of the third or fourth ventricle, whereas age appeared to be unrelated. Patients with tIVH and no major associated injury on CT tended to do well; only one patient with isolated tIVH had a poor outcome. CONCLUSIONS: Traumatic IVH is rare and is associated with poor outcomes that seem to be the consequence of associated injuries. Isolated tIVH patients who are clinically well appear to have a functional outcome; we were unable to identify a case of isolated tIVH, combined with a normal neurologic examination, resulting in a poor or combined outcome.

Adolescent↗
PubMed2006

Intracranial pathology in elders with blunt head trauma.

OBJECTIVES: To examine presentations and prevalence of head injury among elder victims of blunt trauma and to estimate the prevalence of occult injuries associated with a normal level of consciousness, absence of neurologic deficit, and no evidence of significant skull fracture. METHODS: The study population consisted of all patients aged 65 years or older enrolled in the National Emergency X-Radiography Utilization Study (NEXUS) II head injury cohort. The authors assessed the prevalence and patterns of intracranial injuries among this cohort and compared the prevalence of specific presenting signs and symptoms among injured and uninjured patients. An occult injury subcohort was also constructed, and injury prevalence was examined among this group. RESULTS: A total of 1,934 elder patients were identified among the 13,326 subjects in NEXUS II (14.5%). Significant intracranial injury, defined as an injury that typically requires procedural intervention or is associated with persistent neurologic impairment or long-term disability, was found in 178 elder patients (9.2%; 95% confidence interval = 8.0% to 10.6%) as compared with 697 individuals among 11,392 younger patients (6.1%; 95% confidence interval = 5.7% to 6.6%). Focal neurologic deficits were present in 55.8% of elder patients with injury. Prevalence of specific injuries among elder and younger patients, respectively, included the following: subdural hematoma, 4.4% and 2.4%; contusion, 4.0% and 3.2%; epidural hematoma, 0.5% and 1.0%; and depressed skull fracture, 0.2% and 0.5%. Forty-two elder patients (2.2%) had an occult injury, compared with only 92 younger patients (0.8%). CONCLUSIONS: Elder patients with head trauma are at higher risk of developing a significant intracranial injury, including subdural and epidural hematoma. An occult presentation is also more common in elders.

Age Distribution↗
PubMed2005

Injuries missed by limited computed tomographic imaging of patients with cervical spine injuries.

STUDY OBJECTIVE: It has been prominently suggested that computed tomographic (CT) imaging is unnecessary in evaluating patients who have one of a number of specific index cervical spine injuries identified on plain radiographs. We seek to evaluate this recommendation by examining how frequently patients with these index cervical spine injuries have additional secondary injuries that are missed on plain radiography. METHODS: We identified all patients in the National Emergency X-Radiography Utilization Study (NEXUS) cervical spine data set who had an index cervical spine injury identified by plain radiography. We reviewed all radiographic studies done on each of these patients, including CT, to determine whether any patient sustained additional cervical spine injuries not visualized on plain radiographs. RESULTS: Of 818 patients with cervical spine injuries in NEXUS, 224 had one of these index cervical spine injuries diagnosed on plain film radiography. Eighty-one of these 224 patients (36.2%; 95% confidence interval [CI] 29.9% to 42.8%) had at least 1 secondary injury that was not identified on plain radiography. A noncontiguous spinal injury was found in 22 of these 81 patients (27.2%; 95% CI 17.9% to 38.2%) with multiple cervical spine injuries. CONCLUSION: More than a third of patients who had one of the index cervical spine injuries sustained a secondary injury that was not diagnosed by plain radiography, and approximately one fourth of the patients with multiple cervical spine injuries have a noncontiguous spinal injury. Guidelines about the necessity for CT scanning in such patients should be reconsidered.

Cervical Vertebrae↗
PubMed2005

Distracting injuries in patients with vertebral injuries.

To describe the prevalence and types of distracting injuries associated with vertebral injuries at all levels of the spine in blunt trauma patients. A prospective cohort study was conducted at an urban Level I trauma center. All patients undergoing radiographic evaluation of the cervical, thoracic, or lumbar vertebrae after blunt trauma were enrolled. Patients had a data collection form completed by the treating physician before radiographic imaging and were evaluated for the following upon initial presentation: tenderness to the cervical, thoracic, or lumbar spine, distracting injuries, altered mental status, alcohol or drug intoxication, or neurological deficits. Patients with distracting injuries as the sole documented indication for vertebral radiographs were reviewed for the types of injuries present. A total of 4698 patients were enrolled in the study. There were 336 (7.2%) patients who had distracting injuries as the sole documented indication for obtaining radiographic studies of the vertebrae. Eight (2.4%, 95% CI 1.0-4.6%) of the 336 patients had 14 acute vertebral injuries including compression fractures (5), transverse process fractures (7), spinous process fracture (1), and cervical spine rotatory subluxation (1). There were 13 thoracolumbar injuries and one cervical spine injury. Distracting injuries in the eight patients with acute vertebral injuries included 13 bony fractures. Distracting injuries in those patients without vertebral injuries included bony fractures (333), lacerations (63), soft tissue contusions (62), head injuries (15), bony dislocations (12), abrasions (11), visceral injuries (8), dental injuries (5), burns (3), ligamentous injuries (3), amputation (1), and compartment syndrome (1). In conclusion, in patients with distracting injuries, bony fractures of any type were important for identifying patients with vertebral injuries. Other types of distracting injuries did not contribute to the sensitivity of the clinical screening criteria in the detection of patients with vertebral injuries.

Adolescent↗
PubMed2005

Developing a decision instrument to guide computed tomographic imaging of blunt head injury patients.

BACKGROUND: Computed tomographic (CT) head scanning of blunt trauma patients is expensive, delays care, and necessitates radiation exposure, while detecting intracranial injuries in a minority of patients. Clinical characteristics may be able reliably identify patients who do not have intracranial injuries and consequently, do no require imaging. METHODS: Physicians assessed blunt trauma patients undergoing imaging for the presence or absence of specific criteria. Recursive partitioning was used to identify criteria that predict intracranial injuries with high sensitivity. RESULTS: Intracranial injuries were found in 917 of 13,728 enrolled patients (6.7%). Injuries were rare among patients under age 65 who had no evidence of skull fracture, scalp hematoma, neurologic deficit, abnormal alertness, abnormal behavior, coagulopathy, or persistent vomiting. These characteristics would have identified 901 injury cases (sensitivity 98.3% [CI: 97.2-99.0]), while classifying 1,752 patients (12.8%) as "low risk." CONCLUSIONS: Clinical characteristics can reliably identify patients who are unlikely to have intracranial injuries and who do not require CT imaging.

Adult↗
PubMed2005

Impact of patient race on receiving head CT during blunt head injury evaluation.

OBJECTIVES: Prior evidence suggests that physicians may alter process of care based on race/ethnicity. The objective of this study was to determine whether race/ethnicity predicts whether a patient receives computed tomography of the head (head CT) during evaluation of blunt head injury. METHODS: This was a nonconcurrent cohort study set in an emergency department of a Level 1 trauma center in a university medical center. Consecutive patients presenting with blunt head injury from January 2000 to December 2000 were enrolled. The main outcome measure was whether or not a patient received head CT during evaluation of blunt head injury. RESULTS: The unadjusted probability of receiving head CT was similar among minority (33.9%; 95% confidence interval [CI] = 30.0% to 38.1%) and non-Hispanic white patients (36.4%; 95% CI = 33.5% to 39.3%). After adjusting for important clinical and socioeconomic predictors, minority patients had a probability of receiving head CT 0.84 times as high as that of non-Hispanic whites, but this result was not statistically significant (95% CI = 0.67 to 1.09). CONCLUSIONS: Minority and non-Hispanic white patients may not have significantly different rates of receiving head CT during evaluation of blunt head injury. A multicenter prospective study is necessary to confirm these preliminary findings.

Adult↗
PubMed2004

Tetanus immunity and physician compliance with tetanus prophylaxis practices among emergency department patients presenting with wounds.

STUDY OBJECTIVE: We determine tetanus seroprotection rates and physician compliance with tetanus prophylaxis recommendations among patients presenting with wounds. METHODS: A prospective observational study of patients aged 18 years or older who presented to 5 university-affiliated emergency departments (EDs) because of wounds was conducted between March 1999 and August 2000. Serum antitoxin levels were measured by enzyme immunoassay with seroprotection defined as more than 0.15 IU/mL. Seroprotection rates, risk factors for lack of seroprotection, and rates of physician compliance with tetanus prophylaxis recommendations by the Advisory Committee on Immunization Practices were determined. RESULTS: The seroprotection rate among 1,988 patients was 90.2% (95% confidence interval 88.8% to 91.5%). Groups with significantly lower seroprotection rates were persons aged 70 years or older, 59.5% (risk ratio [RR] 5.2); immigrants from outside North America or Western Europe, 75.3% (RR 3.7); persons with a history of inadequate immunization, 86.3% (RR 2.9); and persons without education beyond grade school, 76.5% (RR 2.5). Despite a history of adequate immunization, 18% of immigrants lacked seroprotection. Overall, 60.9% of patients required tetanus immunization, of whom 57.6% did not receive indicated immunization. Among patients with tetanus-prone wounds, appropriate prophylaxis (ie, tetanus immunoglobulin and toxoid) was provided to none of 504 patients who gave a history of inadequate primary immunization (of whom 15.1% had nonprotective antibody titers) and to 218 (79%) of 276 patients who required only a toxoid booster. CONCLUSION: Although seroprotection rates are generally high in the United States, the risk of tetanus persists in the elderly, immigrants, and persons without education beyond grade school. There is substantial underimmunization in the ED (particularly with regard to use of tetanus immunoglobulin), leaving many patients, especially those from high-risk groups, unprotected. Better awareness of tetanus prophylaxis recommendations is necessary, and future tetanus prophylaxis recommendations may be more effective if they are also based on demographic risk factors.

Adolescent↗
PubMed2004

Defining "therapeutically inconsequential" head computed tomographic findings in patients with blunt head trauma.

STUDY OBJECTIVE: Many injuries detected by computed tomographic (CT) imaging of blunt head trauma patients are considered "therapeutically inconsequential." We estimate the prevalence of these findings and determine how frequently affected patients had "important neurosurgical outcomes," defined as either a directed intervention or a poor Glasgow Outcome Scale score. METHODS: We prospectively enrolled all blunt head trauma patients undergoing emergency head CT imaging at 18 centers participating in the National Emergency X-radiography Utilization Study II (NEXUS). From these cases, we identified all patients whose official CT reading met predefined criteria for "therapeutically inconsequential" injuries. We obtained detailed follow-up information on all such patients at 6 sites, including the need for neurosurgical intervention and Glasgow Outcome Scale scores. Among patients having "important neurosurgical outcomes," we assessed the frequency of 2 potential clinical identifiers: altered mental status and coagulopathy. RESULTS: "Therapeutically inconsequential" head CT findings were present in 155 of 8,374 subjects (1.85%; 95% confidence interval 1.57% to 2.16%). Sites participating in the follow-up study enrolled 81 of these patients, of whom 10 (12%) had "important neurosurgical outcomes." Follow-up information was available for 9 patients, all of whom had abnormal mental status at CT scanning. Coagulopathy was also present in 5 of 7 patients for whom coagulation status was known. CONCLUSION: "Therapeutically inconsequential" findings are identified in less than 2% of blunt head trauma patients who undergo CT scanning. A small proportion of these patients have an "important neurosurgical outcome," but it appears that such patients may be identified clinically by the presence of abnormal mental status or coagulopathy.

Adolescent↗