Attitudes and Judgment of Emergency Physicians in the Management of Patients with Acute Headache

OBJECTIVES: There is little evidence guiding physicians in the evaluation of acute headache to rule out nontraumatic subarachnoid hemorrhage (SAH). The authors assessed emergency physicians in: 1) their pretest accuracy for predicting SAH, 2) their comfort with not ordering either head computed tomography (CT) or lumbar puncture (LP) in patients with acute headache, and 3) their comfort with not ordering head CT before performing LP in patients with acute headache. METHODS: This two-and-a-half-year prospective cohort study was conducted in three tertiary care university emergency departments with 51 emergency physicians. Consecutive patients more than 15 years of age with a nontraumatic, acute headache (onset to peak headache less than one hour) and normal results on neurologic examination were enrolled. Patients known to have cerebrospinal fluid shunt, aneurysm, or brain neoplasm, and patients with recurrent headaches of the same intensity/character as their current headache were excluded. Physicians recorded their pretest probability for SAH and their comfort with performing either no tests or an LP without first obtaining head CT. RESULTS: The authors enrolled 747 patients (mean age 42.8 years; 60.1% female; 77.0% their worst headache; 83.4% had CT and/or LP), including 50 (6.7%) with SAHs. Physicians reported being "uncomfortable" or "very uncomfortable" with performing no test in 75.4% of cases and being "uncomfortable" or "very uncomfortable" with performing LP without CT in 49.6% of cases. The area under the receiver operating characteristic (ROC) curve for SAH was 0.85 (95% CI = 0.80 to 0.91). CONCLUSIONS: Physicians were able to moderately discriminate SAH from other causes of headache before diagnostic testing.     

Can Computed Tomography Angiography of the Brain Replace Lumbar Puncture in the Evaluation of Acute‐onset Headache After a Negative Noncontrast Cranial Computed Tomography Scan?

Objectives: The primary goal of evaluation for acute‐onset headache is to exclude aneurysmal subarachnoid hemorrhage (SAH). Noncontrast cranial computed tomography (CT), followed by lumbar puncture (LP) if the CT is negative, is the current standard of care. Computed tomography angiography (CTA) of the brain has become more available and more sensitive for the detection of cerebral aneurysms. This study addresses the role of CT/CTA versus CT/LP in the diagnostic workup of acute‐onset headache. Methods: This article reviews the recent literature for the prevalence of SAH in emergency department (ED) headache patients, the sensitivity of CT for diagnosing acute SAH, and the sensitivity and specificity of CTA for cerebral aneurysms. An equivalence study comparing CT/LP and CT/CTA would require 3,000 + subjects. As an alternative, the authors constructed a mathematical probability model to determine the posttest probability of excluding aneurysmal or arterial venous malformation (AVM) SAH with a CT/CTA strategy. Results: SAH prevalence in ED headache patients was conservatively estimated at 15%. Representative studies reported CT sensitivity for SAH to be 91% (95% confidence interval [CI] = 82% to 97%) and sensitivity of CTA for aneurysm to be 97.9% (95% CI = 88.9% to 99.9%). Based on these data, the posttest probability of excluding aneurysmal SAH after a negative CT/CTA was 99.43% (95% CI = 98.86% to 99.81%). Conclusions: CT followed by CTA can exclude SAH with a greater than 99% posttest probability. In ED patients complaining of acute‐onset headache without significant SAH risk factors, CT/CTA may offer a less invasive and more specific diagnostic paradigm. If one chooses to offer LP after CT/CTA, informed consent for LP should put the pretest risk of a missed aneurysmal SAH at less than 1%. ACADEMIC EMERGENCY MEDICINE 2010; 17:444–451 © 2010 by the Society for Academic Emergency Medicine     

Emergency Department Patient Knowledge,Opinions, and Risk Tolerance Regarding Computed Tomography Scan Radiation

Background

Computed tomography (CT) scanning use for emergency department (ED) patients has increased exponentially since its inception.

Study Objectives

This study aimed to determine what patients view as the risk of radiation from CT scans, their risk tolerance and preference for alternative testing, and their opinions about informed consent and malpractice regarding CT scans.

Methods

A 25-question survey was administered to a random convenience sample of ED patients aged ≥ 18 years by trained research associates.

Results

There were 487 patients approached to be surveyed; 78 patients were excluded, leaving 409 patients (84.0%) responding. Mean patient age was 40.5 (standard deviation [SD] 16.8) years, and 51.5% were female. Three hundred ninety of 409 (95.4%) believed doctors should explain the risks and benefits of CT, and 316/409 (77.3%) thought an informed consent form should be signed. One hundred seventy-nine of 409 (43.8%) patients recognized that there was more radiation from a CT scan than a single chest x-ray study. Three hundred twenty-four of 409 (79.2%) preferred CT angiography over lumbar puncture to exclude subarachnoid hemorrhage. To diagnose appendicitis, 199/409 (48.7%) preferred an ultrasound first even if it meant needing a subsequent confirmatory CT, and 193/409 (47.2%) preferred a CT right away. One hundred sixty-nine of 409 (41.3%) patients would still like to have a CT scan of the head after head trauma even if their physician did not believe the test was indicated.

Conclusion

This study elucidates patient preference and knowledge regarding CT scans. Overall, patients have a poor understanding of CT scan radiation, and desire to have risks explained to them as informed consent prior to the scan.     

应用头颅CT评估颅内高压的可行性分析

目的:应用头颅CT评估颅内高压状况。方法:记录颅内高压症状,检查头颅CT,同时经腰穿测脑脊液压力,比较颅内高压症状、头颅CT形态改变评估颅内高压的敏感性和特异性。结果:应用临床颅内高压症状、蛛网膜下腔消失、脑室受压或消失、基底池受压或消失评估颅内高压的敏感性分别是36%,100%,20%和6%,特异性分别是80%,93%,100%和100%。结论:头颅CT显示蛛网膜下腔消失提示蛛网膜下腔梗阻,即脑脊液回路梗阻,是鉴别颅内高压的敏感标志。     

Variation in use of all types of computed tomography by emergency physicians

Study ObjectivesVariation in computed tomography (CT) use between emergency medicine (EM) physicians may delineate appropriate or inappropriate use. We hypothesize that variation in all types of CT use exists between providers and their use in patients with common chief concerns. We determine EM physicians' variability in CT use of all types and whether high use in one area predicts use of other CT types.MethodsThis was a retrospective study of EM physicians practicing at an 800-bed tertiary level 1 trauma center over a 3.5-year period. Computed tomography rates by type and by patient chief concern were modeled for providers as a function of patient acuity, disposition, age, and time of day using logistic regression.ResultsOf 195 801 eligible visits, 44 724 visits resulted in at least 1 CT scan. The adjusted rate of CT ordering by providers was 23.8% of patient visits, ranging from 11.5% to 32.7% The upper quartile of providers was responsible for 78% of the CT scans ordered above the mean. There was a large variation in use of all types of CT and by chief concern. There was an 8-fold variation in use of CT abdomen in discharged patients. High head CT use by providers predicts high use in all other CT types.ConclusionWe demonstrate a dramatic variation in CT use among EM physicians in all types of CT and common chief concerns. Greater variation was present in patients who were discharged. Large deviation from the mean by a group of providers may suggest inappropriate use.     

6 The AERIS Course: a Focused Abdominal CT Interpretation Course for Abdominal Emergencies Requiring Immediate Surgery

Emergency physicians rely heavily on CT scanning to guide their clinical decisions. A significant number of EDs do not have radiology coverage, especially at night, so the EM physician may be called on to interpret their own CT scans to guide patient management. Many EM physicians look at their CT scans but have never had any formal training. Especially in the setting of acute surgical emergencies such as expanding abdominal aortic aneurysms (AAAs), ruptured spleen or perforated viscus, delay for a radiologist interpretation may result in significant morbidity and mortality. In a collaboration between emergency medicine and radiology, our team created a systematic approach to abdominal CT interpretation designed to help EM physicians perform wet reads on CT scans in the setting of acute surgical emergencies. First, a general survey is done covering all of the important organs such as the aorta, liver, spleen, kidneys, pancreas, stomach and bowel, then a focused scan into the suspected pathology. We put this system onto a Power Point presentation. The two hour presentation covered basic CT anatomic pathology then taught the presentations of common surgical emergencies such as appendicitis, nephrolithiasis and surgical catastrophes such as ruptured AAAs and mesenteric ischemia. The Abdominal Emergencies Requiring Immediate Surgery (AERIS) scan is only intended to be a focused scan for acute surgical pathology, and not to replace the diagnostic scan of a radiologist. This course was given at a single University program, and will be given at residency programs throughout the New York metro area. Eventually we hope that focused CT interpretation will become part of the standardized EM curriculum.     

Sensitivity of New-generation Computed Tomography in Subarachnoid Hemorrhage

Objective: To determine the sensitivity of the initial new-generation CT (NGCT) scan interpretation for detection of acute nontraumatic subarachnoid hemorrhage (SAH) and to decide whether lumbar puncture (LP) should follow a "normal" NGCT scan.
Methods: A retrospective chart review was performed of patients admitted between March 1988 and July 1994 with proven SAH. Exclusion criteria were age <2 years, diagnosis other than acute SAH, history of head trauma within 24 hours before symptom onset, NGCT scan not done before diagnosis, and records not available. Patients were placed into two groups: symptom duration <24 hours (group 1) and >24 hours (group 2) prior to CT scan. The resolution of each NGCT scanner was recorded. An NGCT sceinner was defined as a third-generation scanner or more recent.
Results: Of 349 SAH patients, 181 met inclusion criteria. The sensitivity of NGCT scans for SAH was 93.1% for the group 1 patients ( n = 144) and 83.8% for the group 2 patients ( n = 37). The overall sensitivity was 91.2%. All the patients who had SAH not detected by NGCT scans were diagnosed by LP. There was no significant relationship between NGCT scanner resolution and sensitivity for SAH.
Conclusion: Initial interpretation of NGCT scans to detect SAH does not approach 100% sensitivity. A "normal" NGCT scan does not reliably exclude the need for LP in patients who have symptoms suggestive of SAH.     

Aneurysmal subarachnoid hemorrhage: update for emergency physicians

Aneurysmal subarachnoid hemorrhage (SAH) is a serious cause of stroke that affects 30,000 patients in North America annually. Due to a wide spectrum of presentations, misdiagnosis of SAH has been reported to occur in a significant proportion of cases. Headache, the most common chief complaint, may be an isolated finding; the neurological examination may be normal and neck stiffness absent. Emergency physicians must decide which patients to evaluate beyond history and physical examination. This evaluation--computed tomography (CT) scanning and lumbar puncture (LP)--is straightforward, but each test has important limitations. CT sensitivity falls with time from onset of symptoms and is lower in mildly affected patients. Traumatic LP must be distinguished from true SAH. Cerebrospinal fluid analysis centers on measuring xanthochromia. Debate exists about the best method to measure it--visual inspection or spectrophotometry. An LP-first strategy is also discussed. If SAH is diagnosed, the priority shifts to specialist consultation and cerebrovascular imaging to define the offending vascular lesion. The sensitivity of CT and magnetic resonance angiography are approaching that of conventional catheter angiography. Emergency physicians must also address various management issues to treat or prevent early complications. Endovascular therapy is being increasingly used, and disposition to neurovascular centers that offer the full range of treatments leads to better patient outcomes. Emergency physicians must be expert in the diagnosis and initial stabilization of patients with SAH. Treatment in a hospital with both neurosurgical and endovascular capability is becoming the norm.     

Gross xanthochromia on lumbar puncture may not represent an acute subarachnoid hemorrhage

Headache is a common presenting complaint in the emergency department (ED) that sometimes requires a diagnostic workup including a lumbar puncture (LP). An LP is often used to evaluate patients in the ED for an acute neurologic process. Xanthochromia seen on cerebrospinal fluid from an LP is often considered to be highly suggestive of a subarachnoid hemorrhage. We describe 2 cases where gross xanthochromia was noted during LP but the patients did not have an acute subarachnoid hemorrhage.     

Acute Headache of Recent Onset and Subarachnoid Hemorrhage: A Prospective Study

SYNOPSIS
Twenty-seven patients with acute severe headache of recent onset were prospectively recruited in the Emergency Room. Mean duration of headache was 61 hours. CT scan disclosed subarachnoid bleeding in 4 patients and spinal tap revealed subarachnoid hemorrhage (SAH) in 5 patients with normal CT scan. In most SAH cases pain was bilateral, very intense and involving the occipital region. Four of these patients had doubtful or no nuchal rigidity and in one, pain improved while in the Emergency Room.
In every case with an intense acute severe headache of recent onset CT scan and (if normal) a lumbar puncture are warranted to help rule out a SAH.     

Physician utilization of a portable computed tomography scanner in the intensive care unit

OBJECTIVE: To determine the utilization of a portable computed tomography (CT) scanner for critically ill adult patients in an intensive care unit (ICU). DESIGN: Survey study and retrospective review. SUBJECTS: Critical care attending staff and fellows and neurosurgery residents. SETTING: A university hospital and Level I trauma center with a multitrauma ICU, a neurotrauma ICU, and a neurosurgical ICU. INTERVENTIONS: We surveyed all physicians who ordered portable CT scans from December 1996 through June 1998. Ordering physicians included critical care attending staff and fellows (anesthesiology, surgery, internal medicine) and neurosurgery residents. Physicians who no longer worked at the institution were contacted by mail or fax. Radiology records were reviewed to determine the actual number and type of scans performed. MEASUREMENTS AND MAIN RESULTS: The survey response was 100%. Most physicians reported ordering portable head CT scans (97%), followed by chest CT (88%), abdominal CT (78%), and pelvic CT (34%) scans. Analysis of the actual number of scans performed correlated with these reports (511 head, 115 chest, 88 abdomen, and 87 pelvis). The indication for portable CT scans (as opposed to a "fixed" or "stationary" scans) cited most often was patient severity of illness (77%). Patients on extracorporeal support (93%), those with cardiovascular instability (70%), followed by those with respiratory instability (57%) and neurologic instability (40%) were deemed too ill to transport. If the portable CT scanner was unavailable, however, most physicians (67%) ordered a fixed helical CT scan and the patient was transported to the radiology suite, regardless of medical condition. CONCLUSIONS: Access to a portable CT scanner impacts the physician ordering patterns for ICU patients. We found that 100% of surveyed physicians used the portable CT scanner for critically ill patients when the patient was unstable. If the diagnostic study was deemed medically necessary, and the portable scanner was unavailable, most surveyed physicians ordered a "fixed" helical scan and the patient was transported by an experienced transport team for the study. The portable CT offered an alternative and potentially safer means of obtaining diagnostic studies.     

The Role of Cranial Computed Tomography in the Diagnostic Work-up of Headache

Approximately 18% of all patients referred for a cranial computed tomography complain of headache only.
We reviewed 363 consecutive patients in order to assess the value of this examination in the diagnostic approach.
Despite the vast number of normal examinations (88.4%), we advocate the routine use of a cranial computed tomography in every patient with chronic headache. The cost of the examination can significantly be reduced by performing an unenhanced scan only. An additional contrast-enhanced scan should be obtained if a suspicious lesion is seen. Brain magnetic resonance imaging is not indicated except in the preoperative workup of a lesion visualized on computed tomography.     

Lumbar Puncture First: An Alternative Model for the Investigation of Lone Acute Sudden Headache

Subarachnoid hemorrhage (SAH) is a diagnosis often considered in patients presenting to the ED with acute sudden headaches, but with normal physical examinations. Standard of care today is for these patients to be investigated by noncontrast CT scan followed by lumbar puncture (LP) for negative CTs. However, given that most investigated patients have benign headaches, most of the CT and LP results are normal. The authors studied, by means of a theoretical analysis, the impact of an alternative diagnostic model, in which LP would be the first (and, in most cases, only) diagnostic test for patients suspected of SAH who met lone acute sudden headache (LASH) criteria. Given reasonable assumptions, for every 100 patients investigated, the "LP-first" model would result in 79 to 83 fewer CT scans and only seven to 11 additional LPs, as compared with traditional strategies. Among ED headache patients meeting LASH criteria, the authors believe use of this model could result in more efficient use of resources, minimal additional morbidity, and equal diagnostic accuracy for SAH.     

Proposed Curriculum for an "Observational" International Emergency Medicine Fellowship Program

This article presents information on considerations involved in setting up and conducting fellowship training programs in emergency medicine (EM) for physicians from other countries. General goals for these programs are to assist in providing physicians from other countries with the knowledge and skills needed to further develop EM in their home countries. The authors report their opinions, based on their cumulative extensive experiences, on the necessary and optional structural elements to consider for international EM fellowship programs. Because of U.S. medical licensing restrictions, much of the proposed programs' content would be "observational" rather than involving direct "hands-on" clinical EM training. Due to the very recent initiation of these programs in the United States, there has not yet been reported any scientific evaluation of their structure or efficacy. International EM fellowship programs involving mainly observational EM experience can serve as one method to assist in EM development in other countries. Future studies should assess the impact and efficacy of these programs.     

Lumbar puncture and brain herniation in acute bacterial meningitis: a review

There has been controversy regarding the risk of cerebral herniation caused by a lumbar puncture (LP) in acute bacterial meningitis (ABM). This review discusses in detail the issues involved in this controversy. Cerebral herniation occurs in about 5% of patients with ABM, accounting for about 30% of the mortality. In many reports, LP is temporally strongly associated with this event of herniation and is most likely causative based on pathophysiologic arguments. Although a computed tomography (CT) scan of the head is useful to find contraindications to an LP, a normal CT scan in ABM does not mean that an LP is safe. Clinical signs of "impending" herniation are the best predictors of when to delay an LP because of the risk of precipitating herniation, even with a normal CT scan. Some of these clinical signs to be considered are deteriorating level of consciousness (particularly to a Glasgow Coma Scale of 相似文献   

Subarachnoid hemorrhage diagnosis by computed tomography and lumbar puncture: Are fifth generation CT scanners better at identifying subarachnoid hemorrhage?

This study sought to determine the sensitivity and specificity of modern computed tomography (CT) scans for the diagnosis of subarachnoid hemorrhage (SAH). No studies have been done recently with fifth generation CT scanners to look at the diagnosis of SAH. A retrospective chart review was done of Emergency Department (ED), laboratory, and hospital records at Pitt County Memorial Hospital in Greenville, North Carolina over 1 year from January 1, 2002 to December 31, 2002. Patients presented with headache and had a CT scan of the head with a fifth generation multi-detector CT scanner followed by a lumbar puncture (LP) to rule out SAH. There were 177 patients who presented to the ED with headache and went on to have a CT scan and an LP to rule out SAH. No patients who had a negative CT were found to have a subarachoid hemorrhage. It is concluded that fifth generation CT scanners are probably more sensitive than earlier scanners at detecting SAH.     

Sinus CT scan findings in "sinus headache" migraineurs

OBJECTIVE: To evaluate the sinus CT scan findings in "sinus headache" migraineurs, and to compare the findings to nonmigraine "sinus headache" patients. BACKGROUND: The majority of patients presenting with "sinus headache" satisfy the International Headache Society (IHS) criteria for migraine headache. Few studies have correlated the rhinologic complaints and computed tomography (CT) findings in these patients. METHODS: Thirty-five patients with "sinus headache" were evaluated prospectively and referred for CT of the paranasal sinuses. The CT scans were assessed for sinus abnormality (recorded as a Lund-Mackay [L-M] score) and were analyzed for concha bullosa and septal deviation. The findings in the migraine cohort were compared with the nonmigraine "sinus headache" patients. FINDINGS: Twenty-six patients (74.3%) satisfied the IHS criteria for migraine. The mean CT scan L-M score did not differ significantly between the migraine (2.07) and nonmigraine cohort (2.66). Five of the migraine group had substantial sinus disease radiographically (with L-M scores of 5 or above). Concha bullosa of at least 1 middle turbinate was more common in the nonmigraine cohort. An analysis of the sidedness of the headaches, sinus disease, concha bullosa, and/or septal deviation is presented. CONCLUSIONS: The majority of "sinus headache" patients satisfy the IHS criteria for migraine. Surprisingly, these patients often have radiographic sinus disease. This raises the possibility of selection bias in otolaryngology patients, inaccurate diagnosis, or radiographic sinus disease and migraine as comorbid conditions. Positive migraine histories apparently do not obviate the need for a thorough ENT workup, possibly including CT scanning.     

Impact of CT scan in patients with first episode of suspected nephrolithiasis

This prospective observational outcome study assessed the impact of helical computed tomography (CT) scan in patients with a first episode of suspected nephrolithiasis. Before CT scanning, Emergency Physicians completed a questionnaire, including diagnostic certainty of nephrolithiasis and anticipated patient disposition. Primary outcome measure was the comparison of physician diagnostic certainty and CT scan results. Secondary outcome measures included alternate diagnoses and changes in patient disposition after CT scan. Four categories grouped the pre-CT diagnostic certainty: 0-49%, 50-74%, 75-90%, and 90-100%. The CT scan found urinary calculi in 28.6%, 45.7%, 74.2%, and 80.5% of patients in each category, respectively. CT scanning revealed alternate diagnoses in 40 cases (33.1%). Of these, 19 (47.5%) included other significant pathology. Before CT scanning, physicians planned to discharge 115 patients and admit six patients. After CT scanning, six of the former group were admitted, and five of the latter group were discharged. Patients presenting with a first episode of clinically suspected nephrolithiasis should undergo CT scanning because it enhances diagnostic certainty by identifying alternate diagnoses not suspected on clinical grounds alone.     

The detection of nontraumatic subarachnoid hemorrhage: still a diagnostic challenge

Nontraumatic subarachnoid hemorrhage is one of the most elusive diagnoses in emergency medicine; it is a potentially lethal disease that is often considered and rarely found. The current practice as determined by the American College of Emergency Physicians 1996 Clinical Policy on Headache is a noncontrast head computed tomography (CT) followed by diagnostic lumbar puncture (LP) to exclude subarachnoid hemorrhage. Whereas the guideline does not consider pretest probability of subarachnoid hemorrhage in determining which patients require LP after negative head CT, patients' acceptance of LP, technical aspects of performing a LP in patients with nonideal anatomy, and risks associated with LP must all be considered when choosing to proceed with invasive testing. This article outlines the use of current testing modalities including CT, magnetic resonance imaging, angiography and LP to provide an up-to-date understanding of diagnostic testing for subarachnoid hemorrhage.     

Evaluation of lung ultrasound for the diagnosis of pneumonia in the ED

Objectives

The aim of this study is to assess the ability of bedside lung ultrasound (US) to confirm clinical suspicion of pneumonia and the feasibility of its integration in common emergency department (ED) clinical practice.

Methods

In this study we performed lung US in adult patients admitted in our ED with a suspected pneumonia.Subsequently, a chest radiograph (CXR) was carried out for each patient. A thoracic computed tomographic (CT) scan was made in patients with a positive lung US and a negative CXR. In patients with confirmed pneumonia, we performed a follow-up after 10 days to evaluate clinical conditions after antibiotic therapy.

Results

We studied 49 patients: pneumonia was confirmed in 32 cases (65.3%). In this group we had 31 (96.9%) positive lung US and 24 (75%) positive CXR. In 8 (25%) cases, lung US was positive with a negative CXR. In this group, CT scan always confirmed the US results. In one case, US was negative and CXR positive. Follow-up turned out to be always consistent with the diagnosis.

Conclusion

Considering that lung US is a bedside, reliable, rapid, and noninvasive technique, these results suggest it could have a significant role in the diagnostic workup of pneumonia in the ED, even if no sensitivity nor specificity can be inferred from this study because the real gold standard is CT, which could not be performed in all patients.