Diagnostic accuracy of secondary ultrasound exam in blunt abdominal trauma

Prehospital ultrasound scanning for abdominal free fluid detection in trauma patients: a systematic review and meta-analysis

INTRODUCTION

Focused assessment with sonography for trauma helps detect abdominal free fluid. Prehospital ultrasound scanning is also important because the early diagnosis of hemoperitoneum may reduce the time to definitive treatment in the hospital. This study investigated whether prehospital ultrasound scanning can help detect abdominal free fluid.

MATERIALS AND METHODS

In this systematic review, relevant databases were searched for studies investigating prehospital ultrasound examinations for abdominal free fluid in trauma patients. The prehospital ultrasound results were compared with computed tomography, surgery, or hospital ultrasound examination data. The pooled sensitivity and specificity values were analyzed using forest plots. The overall predictive power was calculated by the summary receiver operating characteristic curve. The quality of the included studies was assessed using the quality assessment of diagnostic accuracy studies tool. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) was performed to assess the certainty of evidence.

RESULT

This meta-analysis comprised six studies that included 1356 patients. The pooled sensitivity and specificity values were 0.596 (95% confidence interval [CI] = 0.345-0.822) and 0.970 (95% CI = 0.953-0.983), respectively. The pooled area under the summary receiver operating characteristic curve was 0.998. The quality assessment tool showed favorable results. In the GRADE analysis, the quality of evidence was very low for sensitivity and high for specificity when prehospital ultrasound was used for hemoperitoneum diagnosis.

CONCLUSION

The specificity of abdominal free fluid detection using prehospital ultrasound examinations in trauma patients was very high.

Influence of operative timing on perioperative outcomes of patients with the seatbelt sign

Background

The seatbelt sign (SBS) is a pattern of bruising/contusions on the chest and abdominal wall following motor vehicle collisions. The aim of this analysis is to investigate the influence of time to surgery following identification of the SBS on perioperative outcomes.

Methods

A retrospective review of the Trauma Quality Improvement Program database from 2017 to 2019 was performed. Patients included in this retrospective analysis were involved in motor vehicle collisions, experienced blunt abdominal trauma, presented with skin abrasions/contusions in the SBS distribution, were hemodynamically stable, and underwent laparotomy. Demographics, vital signs, injury severity score, Glasgow coma scale, preoperative CT scans (P-CT), and time from presentation to surgery were recorded. Time from presentation to surgery was subdivided by data quartiles as immediate (<1.3 h), early (1.3-4 h), and delayed (>4 h). The influence of operative timing on postoperative mortality, hospital length of stay (LOS), intensive care unit (ICU) LOS, and ventilator days was assessed in multivariate analyses.

Results

A total of 1523 patients were included; 280 underwent immediate, 610 early, and 633 delayed surgery. Patients undergoing surgery in the early and delayed groups who received P-CT scans had shorter mean times to operation (4.52 h vs 5.24 h, p < 0.01). In multivariate analysis, patients who underwent delayed surgery stayed in the hospital 2.5 days longer (p < 0.001), spent 2.8 additional days in the ICU (p < 0.001), and spent 3.75 additional days on a ventilator (p < 0.001) than patients who received early surgery. Within the early and delayed surgical groups, P-CT was associated with lower mortality (OR 0.46 95 % CI 0.24-0.88, p < 0.01) in multivariate analysis.

Conclusions

Early surgical intervention was associated with improved patient outcomes by reducing hospital and ICU LOS and ventilator days. Conducting P-CT reduced the time to surgery and mortality. Utilization of P-CT for screening hemodynamically stable patients with the SBS upon admission may expedite identification of the potential need for surgical management of abdominal injury.

Systematic Sonography Looking for Occult Wounds: accuracy of an abdominal ultrasound adjunct in penetrating trauma

BACKGROUND

Systematic Sonography Looking for Occult Wounds (SSLOW) in trauma is a novel technique for the evaluation of intra-abdominal wounds in penetrating trauma. No data exist regarding the effectiveness. The objective of this study was to evaluate the accuracy of the SSLOW exam.

METHODS

This is a prospective collected case series conducted over a period of 10 months and took place at the Accident and Emergency Department (A&E) of the Georgetown Public Hospital Corporation (GPHC). The study enrolled patients presenting to the A&E who were 16 years old or greater with penetrating abdominal trauma. All patients with penetrating trauma received an E-FAST examination. If the E-FAST examination was negative, a SSLOW examination was completed. The sonographer evaluated for free fluid collection between the loops of bowel. The results of the SSLOW were compared to usual care (surgery consult, serial abdominal and E-FAST exams, laparotomy, and 7-day follow-up) and then categorized into four groups: true positive, false positive, true negative, and false negative. These results lead to four categorical values. From these results, sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratios were calculated.

RESULTS

There were 5 (12%) true positives, 1 (2%) false positive, 37 (86%) true negatives, and zero (0%) false negative. The SSLOW was 100% sensitive (95% CI 5-100%) and 97% specificity (95% CI 74-96%). There was an 80% positive predictive value (95% CI 1.0-64% 95% CI) and 100% negative predictive value (95% CI 88-100%). The positive likelihood ratio was 8.4 (95% CI 3.69-19.1) and negative likelihood ratio was 0.

CONCLUSION

The SSLOW examination may be a useful tool in the evaluation of penetrating abdominal injuries.

Paramedic point of care ultrasound at Australian mass gatherings

Point of care ultrasound (POCUS) is not traditionally performed by paramedics, and where it is used, is generally limited to resuscitative-type ultrasound examinations. We describe a select series of patient care cases collected between August 2017 and February 2018 which are the first known examples of expanded POCUS performed by a paramedic in this context. These point of care scans were performed for both high and lower acuity patient presentations and are felt to have contributed to improved decision-making in the treatment and onward referral of patients in the Australian festival and event medicine.

Diagnostic accuracy of Focused Assessment with Sonography for Trauma for blunt abdominal trauma in the Eastern Region of Saudi Arabia

Objectives:

To determine the diagnostic accuracy of Focused Assessment with Sonography for Trauma (FAST) in blunt abdominal trauma caused by motor vehicle accidents at our Hospital in Dhahran city.

Methods:

This descriptive, observational study was conducted in the Radiology Department at King Fahad Military Medical Complex Dhahran, Saudi Arabia between September 2016 and September 2017. All adult patients (n=105) involved in motor vehicle accidents with blunt abdominal injury on presentation were retrospectively reviewed for FAST and CT scans for detection of free fluid. Focused assessment with sonography for trauma studies were conducted or supervised by senior registrar of general surgery (trauma team leader). Computed tomography findings were reviewed by 2 experienced radiologists. High and low-grade solid abdominal visceral (liver, spleen, kidney) injuries were identified on CT scans. Focused assessment with sonography for trauma and CT scan findings were identified as ‘positive’ and ‘negative’ for presence and absence of free fluid respectively. Outcomes of FAST were presented on a 2x2 contingency table.

Results:

Sensitivity of FAST in detecting intraperitoneal free fluid was calculated as 76.1% (95% confidence interval [CI], 64.14-85.69%), specificity 84.2% (95% CI, 68.75-93.98%) and accuracy 79% (95% CI, 70.01-86.38%). Focused assessment with sonography for trauma detected free fluid in most cases of high-grade solid visceral injuries. Nearly half of true-negative cases were having low grade visceral or other injuries.

Conclusion:

Focused assessment with sonography for trauma is an important tool in initial assessment of suspected blunt abdominal injury patients with high sensitivity and specificity. A negative FAST does not exclude low grade solid visceral or other injuries.

Senior general surgery residents can be trained to perform focused assessment with sonography for trauma patients accurately

PURPOSES

Researchers studying trauma have found that physicians are able to perform a focused assessment with sonography for trauma (FAST) with minimal training and achieve ideal accuracy. However, there are currently no consensus or standard guidelines regarding the performance of this assessment. The aim of our study was to clarify the value of FAST performed by well-qualified senior general surgery residents in cases of suspected blunt abdominal trauma, which presents an important diagnostic problem in emergency departments.

METHODS

This was a retrospective study in the emergency department (ED) of our hospital performed from January 2011 to September 2013. Patients were included if they (1) had undergone a FAST examination performed by qualified residents and (2) had received subsequent formal radiographic or surgical evaluations. The results were compared against subsequent surgical findings or formal Department of Radiology reference standards.

RESULTS

Among the 438 patients enrolled, false-negative results were obtained in 8 and false-positive results in 5. Only one patient was missed and required laparotomy to repair a small intestine perforation. The sensitivity and specificity were 87 and 99%, respectively; the accuracy was 97%.

CONCLUSIONS

Senior general surgery residents can be trained to perform accurate FAST examinations on trauma patients.

Diagnosis of Atypical Chest Pain Using Ultrasound

While the common organs assessed in chest pain are the heart, lungs, and inferior vena cava, one must also consider other diagnoses. Splenic rupture can be either traumatic or atraumatic, and splenomegaly can make this vulnerable organ even more susceptible to injury. A case is reported of a patient who presented to the emergency department with a complaint of left-sided chest pain; a focused assessment with sonography for trauma (FAST) examination showed significant intraperitoneal free fluid consistent with splenic injury. The role of bedside sonography in acquiring a rapid and accurate diagnosis is discussed.