Chuan Zhou

Prevalence of incidental findings in trauma patients detected by computed tomography imaging

STUDY OBJECTIVE The primary intention of spiral computed tomography (SCT) in trauma patients is to identify significant injuries. However, unanticipated information is often discovered. We hypothesize that SCT often identifies clinically significant incidental findings in trauma patients. METHODS This was a retrospective protocol chart review of consecutive adult trauma patients seen at a level I trauma center. A complete SCT was defined as computed tomography imaging of the head, cervical spine, chest, abdomen, and pelvis, thoracic, and lumbar spine. Incidental findings were classified into 2 categories: type 1, which requires urgent evaluation, and type 2, which requires informing the patient but does not mandate urgent follow-up. RESULTS We reviewed 3246 patient charts and 3092 met inclusion criteria. Type 1 findings were reported in 990 (32.0%; 95% confidence interval [CI], 30.4%-33.7%) patients. Type 2 findings were found in 1274 (41.2%; 95% CI, 39.5%-42.9%) patients. Female sex (odds ratio, 1.38; 95% CI, 1.16-1.65) and older age (odds ratio, 2.61; 95% CI, 2.33-2.93) were independently associated with a higher prevalence of type 1 findings. There were 631 incidental findings concerning for neoplasm, which included 196 pulmonary nodules, 99 liver, 36 renal, 23 brain, and 11 breast masses. CONCLUSIONS A significant number of trauma patients evaluated with SCT are diagnosed with potentially serious incidental findings. For long-term care and medicolegal concerns, physicians need to inform patients of these incidental findings and the need for further evaluation.

A randomized, placebo-controlled trial of ondansetron, metoclopramide, and promethazine in adults

OBJECTIVES The objective of the study was to assess whether ondansetron has superior nausea reduction compared with metoclopramide, promethazine, or saline placebo in emergency department (ED) adults. METHODS This randomized, placebo-controlled, double-blinded superiority trial was intended to enroll a convenience sample of 600 patients. Nausea was evaluated on a 100-mm visual analog scale (VAS) at baseline and 30 minutes after treatment. Patients with a minimum preenrollment VAS of 40 mm were randomized to intravenous ondansetron 4 mg, metoclopramide 10 mg, promethazine 12.5 mg, or saline placebo. A 12-mm VAS improvement in nausea severity was deemed clinically important. We measured potential drug adverse effects at baseline and 30 minutes. Patients received approximately 500 mL of saline hydration during the initial 30 minutes. RESULTS Of 180 subjects who consented, 163 completed the study. The median age was 32 years (interquartile range, 23-47), and 68% were female. The median 30-minute VAS reductions (95% confidence intervals) and saline volume given for ondansetron, metoclopramide, promethazine, and saline were -22 (-32 to -15), -30 (-38 to -25.5), -29 (-40 to -21), and -16 (-25 to -3), and 500, 500, 500, and 450, respectively. The median 30-minute VAS differences (95% confidence intervals) between ondansetron and metoclopramide, promethazine, and saline were -8 (-18.5 to 3), -7 (-21 to -5.5), and 6 (-7 to 20), respectively. We compared the antiemetic efficacy across all treatments with the Kruskal-Wallis test (P = .16). CONCLUSIONS Our study shows no evidence that ondansetron is superior to metoclopramide and promethazine in reducing nausea in ED adults. Early study termination may have limited detection of ondansetrons superior nausea reduction over saline.

Bedside end-tidal CO2 tension as a screening tool to exclude pulmonary embolism

End tidal carbon dioxide tension (PET,CO2) is a surrogate for dead space ventilation which may be useful in the evaluation of pulmonary embolism (PE). We aimed to define the optimal PET,CO2 level to exclude PE in patients evaluated for possible thromboembolism. 298 patients were enrolled over 6 months at a single academic centre. PET,CO2 was measured within 24 h of contrast-enhanced helical computed tomography, lower extremity duplex or ventilation/perfusion scan. Performance characteristics were measured by comparing test results with clinical diagnosis of PE. PE was diagnosed in 39 (13%) patients. Mean PET,CO2 in healthy volunteers did not differ from PET,CO2 in patients without PE (36.3±2.8 versus 35.5±6.8 mmHg). PET,CO2 in patients with PE was 30.5±5.5 mmHg (p<0.001 versus patients without PE). A PET,CO2 of ≥36 mmHg had optimal sensitivity and specificity (87.2 and 53.0%, respectively) with a negative predictive value of 96.6% (95% CI 92.3–98.5). This increased to 97.6% (95% CI 93.2–99.) when combined with Wells score <4. A PET,CO2 of ≥36 mmHg may reliably exclude PE. Accuracy is augmented by combination with Wells score. PET,CO2 should be prospectively compared to D-dimer in accuracy and simplicity to exclude PE.

Innovative application of cerebral RSO2 monitoring during shunt tap in pediatric ventricular malfunctioning shunts

Objective This study aimed to determine the reliability and potential application of cerebral regional tissue oxygenation (rSO2) monitoring in malfunctioning ventricular shunts during tap. Methods This is a prospective case series using convenience sample in subjects with confirmed malfunctioning shunt who had left and right cerebral rSO2 monitoring every 5 seconds before, during, and 1 hour after shunt tap. Results Ninety-four subjects had cerebral rSO2 monitoring. Sixty-three subjects had proximal malfunctions, and 31 subjects had distal shunt malfunctions. The intrasubject’s cerebral rSO2 trend and variability at pretap, during, and posttap times were highly correlated. Overall, the average rSO2 is lower in pretap as compared with posttap. Left cerebral rSO2 had lower means and larger SD as compared with right cerebral rSO2. Left pretap and posttap cerebral rSO2 variability was significantly associated with the location of shunt malfunction regardless of pretap, during, or posttap periods (P < 0.001), whereas right rSO2 variability was not predictive for malfunction location. Left cerebral rSO2 variability showed utility for identifying the location of malfunction with area under the receiver operating characteristic curve equal to 0.8. Conclusions Reliable cerebral rSO2 readings before, during, and after shunt tap were demonstrated. Left cerebral rSO2 changes from before to after shunt tap were more predictive for shunt malfunction location than right cerebral rSO2 changes. Observing cerebral rSO2 changes in relationship to shunt tap represents a potential surrogate in measuring cerebral pressures and blood flow changes after cerebral spinal fluid drainage. Significantly greater cerebral rSO2 changes occur for distal malfunction versus proximal malfunction after shunt tap, indicating its potential as an adjunct tool for detecting shunt malfunction type.