Marc A. Camacho

Anterior Versus Lateral Needle Decompression of Tension Pneumothorax: Comparison by Computed Tomography Chest Wall Measurement

OBJECTIVES Recent research describes failed needle decompression in the anterior position. It has been hypothesized that a lateral approach may be more successful. The aim of this study was to identify the optimal site for needle decompression. METHODS A retrospective study was conducted of emergency department (ED) patients who underwent computed tomography (CT) of the chest as part of their evaluation for blunt trauma. A convenience sample of 159 patients was formed by reviewing consecutive scans of eligible patients. Six measurements from the skin surface to the pleural surface were made for each patient: anterior second intercostal space, lateral fourth intercostal space, and lateral fifth intercostal space on the left and right sides. RESULTS The distance from skin to pleura at the anterior second intercostal space averaged 46.3 mm on the right and 45.2 mm on the left. The distance at the midaxillary line in the fourth intercostal space was 63.7 mm on the right and 62.1 mm on the left. In the fifth intercostal space the distance was 53.8 mm on the right and 52.9 mm on the left. The distance of the anterior approach was statistically less when compared to both intercostal spaces (p < 0.01). CONCLUSIONS With commonly available angiocatheters, the lateral approach is less likely to be successful than the anterior approach. The anterior approach may fail in many patients as well. Longer angiocatheters may increase the chances of decompression, but would also carry a higher risk of damage to surrounding vital structures.

A Prospective Pilot Study of Predictors of Acute Stroke in Emergency Department Patients With Dizziness

OBJECTIVE To prospectively examine undifferentiated emergency department (ED) patients with dizziness to identify clinical features associated with acute stroke. PATIENTS AND METHODS We conducted a pilot study from November 1, 2009, through October 30, 2010, of adult patients with dizziness presenting to 3 urban academic EDs. Data collected included demographic characteristics, medical history, presenting symptoms, examination findings, clinician pretest probability of stroke, and neuroimaging results. Logistic regression was used to identify variables with a significant association with acute stroke (P<.05). RESULTS During the study period, we enrolled 473 patients (mean ± SD age, 56.7±19.3 years; 60% female; and 71% white). We found 30 acute, serious diagnoses (6.3%), including 14 ischemic strokes, 2 subarachnoid hemorrhages, 7 mass lesions, 2 demyelinating lesions, 2 severe vertebral artery stenoses, 2 acute coronary syndromes, and 1 case of hydrocephalus and meningitis). We identified 6 clinical variables associated with stroke: age (odds ratio [OR], 1.04; 95% CI, 1.0-1.07), hyperlipidemia (OR, 3.62; 95% CI, 1.24-10.6), hypertension (OR, 4.91; 95% CI, 1.46-16.5), coronary artery disease (OR, 3.33; 95% CI, 1.06-10.5), abnormal tandem gait test result (OR, 3.13; 95% CI, 1.10-8.89), and high or moderate physician pretest probability for acute stroke (OR, 18.8; 95% CI, 4.72-74.5). CONCLUSIONS Most ED patients with dizziness do not have a serious cause of their symptoms. Although the small number of outcomes precluded development of a multivariate model, we identified several individual high-risk variables associated with acute ischemic stroke. Further study will be needed to validate the findings of this pilot investigation.

Emergency Medicine Physician Ordering of Abdominal Radiographs for Acute, Non Traumatic, Abdominal Pain

Introduction: The purpose of this study was to document, classify, and analyze the rationale behind the use of abdominal radiography (AXR) by Emergency Department physicians (EDMDs) in the setting of acute non-traumatic abdominal pain. Methods: A prospective observational cohort study of EDMDs in the diagnostic evaluation of patients with acute, non-traumatic abdominal pain for whom AXR was requested. Prospectively acquired data included the experience level of the EDMD, the provisional diagnosis prior to AXR, the likely impact of the results on the decision to order further imaging, and the EDMDs’ estimate of the likelihood of having a positive finding on AXR. Results: Results from 169 patients were included. The most common provisional diagnoses provided at the time of ordering the AXR were obstruction (43%), constipation (14.8%), perforation (8.3%), non-specific abdominal pain (6.5%), renal colic (3.6%) and other (18.9%). The reason for ordering the AXR was to establish the provisional diagnosis (44.4%), to exclude a more serious diagnosis (33.1%) and other (20.7%). Overall 70.4% of AXRs were interpreted as normal, 23 (13.6%) of the studies were read as positive with 78% of these being positive for small bowel obstruction. An additional 27 (16%) studies were equivocal. In 40% of patients with an AXR, no CT was obtained later. Conclusion: Physicians’ pretest probability of a positive finding was found to increase the likelihood of a positive AXR. By limiting the use of AXR to specific diagnoses and guided by the physician’s own determination of likelihood of positive results, imaging resources might be able to be used more efficiently, decreasing patient’s length of stay, radiation exposure, and technician’s and physician’s time.