Prospective comparison of diagnostic peritoneal lavage, computed tomographic scanning, and ultrasonography for the diagnosis of blunt abdominal trauma

Emergent abdominal sonography as a screening test in a new diagnostic algorithm for blunt trauma

Although there is an interest in emergent abdominal sonography (EAS), the clinical utilization of EAS in North America is minimal. The purpose of this study was to develop a new diagnostic algorithm for blunt abdominal injury based on a prospective blinded comparison of EAS, diagnostic peritoneal lavage (DPL), and computed tomography (CT). EAS (+ = fluid, - = no fluid) was performed before the DPL or CT, in 400 patients with a mean Injury Severity Score of 26; 293 had a CT and 107 had a DPL. The EASs required 2.6 +/- 1.2 minutes with 82% < or = 3 minutes. The accuracy of EAS for free fluid was 94% with a positive and negative predictive value of 82 and 96%, respectively. Only 1 of 338 patients with EAS- had an acute therapeutic laparotomy. Three patients with EAS- had a delayed laparotomy based on evolving clinical findings. The radiologists interpretation of the EAS video disagreed with the clinician sonographer in only 3% of cases. Based on these results, a diagnostic algorithm was developed using EAS as a screening test with selective use of DPL and CT. Emergent abdominal sonography performed by clinician sonographers is a rapid and accurate test for peritoneal fluid in blunt trauma victims, and the need for laparotomy in patients with a negative EAS is rare. Our study supports the routine use of EAS as a screening test in a diagnostic algorithm for the evaluation of blunt abdominal trauma.

The role of surgeon-performed ultrasound in patients with possible cardiac wounds

OBJECTIVE

The authors evaluate surgeon-performed ultrasound in determining the need for operation in patients with possible cardiac wounds.

BACKGROUND DATA

Ultrasound quickly is becoming part of the surgeon's diagnostic armamentarium; however, its role for the patient with penetrating injury is less well-defined. Although accurate for the detection of hemopericardium, the lack of immediate availability of the cardiologist to perform the test may delay the diagnosis, adversely affecting patient outcome. To be an effective diagnostic test in trauma centers, ultrasound must be immediately available in the resuscitation area and performed and interpreted by surgeons.

METHODS

Surgeons performed pericardial ultrasound examinations on patients with penetrating truncal wounds but no immediate indication for operation. The subcostal view detected hemopericardium, and patients with positive examinations underwent immediate operation by the same surgeon. Vital signs, base deficit, time from examination to operation, operative findings, treatment, and outcome were recorded.

RESULTS

During 13 months, 247 patients had surgeon-performed ultrasound. There were 236 true-negative and 10 true-positive results, and no false-negative or false-positive results; however, the pericardial region could not be visualized in one patient. Sensitivity, specificity, and accuracy were 100%; mean examination time was 0.8 minute (246 patients). Of the ten true-positive examinations, three were hypotensive. The mean time (8 patients) from ultrasound to operation was 12.1 minutes; all survived. Operative findings (site of cardiac wounds) were: left ventricle (4), right ventricle (3), right atrium (2), right atrium/superior vena cava (1), and right atrium/inferior vena cava (1).

CONCLUSIONS

Surgeon-performed ultrasound is a rapid and accurate technique for diagnosing hemopericardium. Delay times from admission to operating room are minimized when the surgeon performs the ultrasound examination.

Laparoscopy in trauma

Laparoscopy is a nearly century-old technique that has experienced a resurgence of interest from surgeons since the development of technology that has broadened its applications. Although laparoscopy has been used to evaluate patients with possible abdominal trauma, its use for this purpose is limited by the availability of other diagnostic procedures that may be more suitable for particular circumstances and are more accurate for certain injuries. Laparoscopy is contraindicated in patients who are hypovolemic or hemodynamically unstable and should not be performed in patients with clear indications for celiotomy. It may not be appropriate for patients with cardiac dysfunction, nor for those with significant head injuries who are at risk for intracranial hypertension. Its best applications may be in stable patients with stab wounds or those with tangential gunshot wounds of the abdomen. The likelihood of missing hollow visceral injuries depends upon the indications for conversion to celiotomy. If peritoneal violation or the presence of a small amount of blood in the peritoneal cavity is used as an indication for celiotomy, then the missed injury rate will be low but the unnecessary celiotomy rate will be diminished only slightly compared with a policy of mandatory celiotomy. Excessive enthusiasm for laparoscopy in trauma might result in its use when other diagnostic measures or simple observation are more appropriate. The desire to perform a procedure can be compelling, especially in circumstances in which the general surgeon would not operate upon a patient but simply provide postoperative care after other surgeons have operated. The use of laparoscopy for these purposes can only be condemned, as it increases the costs and risks of care without improving the outcome. The role of laparoscopy in trauma is evolving, and further research into its diagnostic role and therapeutic applications is clearly needed.

A prospective evaluation of abdominal ultrasound in blunt trauma: is it useful?

OBJECTIVE

The purpose of this study is to evaluate the utility and feasibility of abdominal ultrasound (US) in blunt trauma patients.

DESIGN

This prospective study examined the operational issues and the diagnostic accuracy of US in selected blunt trauma patients triaged to a Level 1 trauma center.

MATERIALS AND METHODS

All patients were evaluated by an attending trauma surgeon and our usual criteria for objective evaluation of the abdomen were applied. US was performed by US technicians and interpreted by the trauma surgeon. We prospectively evaluated the availability (time to arrival), the ease with which the US could be integrated into the resuscitation (minutes to start after arrival), and the time required to perform the study. The US results were compared to diagnostic peritoneal lavage and computed tomography findings, clinical course, operative findings, and to repeat US examinations to determine sensitivity, specificity, and usefulness.

MEASUREMENTS AND MAIN RESULTS

A total of 800 US studies were performed over 15 months. In four cases (0.5%), the US was incomplete for technical reasons. The results in the remaining 796 studies were as follows: [table: see text] The average time to arrival of the US was 17.3 minutes (range 0-120) and the average minutes to start after arrival was 7.0 (range 1-49). The average time required to perform the study was 10.6 minutes (range 2-26).

CONCLUSIONS

This study demonstrates that US can be obtained rapidly, integrated into the resuscitation, and completed quickly. US provides a highly accurate, noninvasive method to evaluate the abdomen in the blunt trauma patient, and has supplanted the previously used methods at this institution.

Ultrasonography for the initial evaluation of blunt abdominal trauma: A review of prospective trials

Many trauma centers are considering the addition of diagnostic ultrasonography to their trauma protocols. However, a diagnostic imaging application should not be used in general clinical practice until its efficacy has been demonstrated. A literature search was conducted for prospective trials on the use of ultrasound in evaluation of blunt abdominal trauma. Each study was evaluated with the use of an efficacy assessment model. Within this framework, clinical outcomes were classified according to the following efficacy assessment parameters: technical capacity, diagnostic accuracy, diagnostic effect, therapeutic effect, and patient outcome. This model also provided a systematic process for grading the quality of research methods used to obtain each outcome. Eleven trials were found that fulfilled the study criteria, and all of them concluded that ultrasound was valuable for assessment of blunt intraperitoneal trauma. Frequent methodologic flaws were detected in these studies. None of these trials determined therapeutic effect or patient outcome. The criteria for clinical efficacy were not fulfilled. Additional trials should be conducted before ultrasound is accepted as a standard diagnostic test for the evaluation of blunt abdominal trauma.

Computed tomography vs clinical and multidisciplinary procedures for early evaluation of severe abdomen and chest trauma--a cost analysis approach

OBJECTIVE

To compare contrast computed tomography (CT) for evaluating abdominal and vascular chest injuries after emergency room resuscitation with multidisciplinary management based on bedside procedure (BP), e.g., peritoneal lavage, abdomen ultrasonography urography and, if indicated, CT and/or aortography or transesophageal echocardiography.

DESIGN

Randomized study.

SETTING

Emergency, critical care and radiology departments in a trauma center.

PATIENTS

The study was performed in 103 severe blunt trauma patients with a revised trauma index < 8, admitted over a 16 month period and divided into group (G1, n = 52, CT management) and group 2 (G2, n = 51, BP management).

INTERVENTIONS

A relative direct cost scale used in our trauma center was applied, and cost units (U) were assigned to each diagnostic test for cost-minimization analysis (abdomen ultrasonograph = 7.5 U, peritoneal lavage = 8 U, urography = 9 U, computed tomography = 9 U, transesophageal echocardiography = 13.5 U, and aortography = 15 U). One unit is approximately equivalent to $43.7.

RESULTS

Injury severity score (ISS) was 31.7 +/- 15.4 in G1 and 33.8 +/- 18.3 in G2. Sensitivity for CT was 90.4% (G1) vs 72.5% for BP (G2) in abdomen (P < 0.01) and 60% in chest for evaluating mediastinal hematoma etiology (G1). As Table 2 shows, G1 needed 59 tests for evaluating injuries (1.1 +/- 0.3 tests patient) while G2 required 81 tests (1.68 +/- 0.8 tests/patient) (P < 0.01). The total relative cost was 538 U for G1, 7.04 +/- 2.2 U cost/injury and 10.3 +/- 3.3 U/evaluation of trauma vs 698 U for G2, 9.84 +/- 5.03 U cost/injury and 13.68 +/- 8.5 U/evaluation (P < 0.05).

CONCLUSIONS

This cost-minimization study suggests that CT is a more cost-effective method for the post-emergency room resuscitation evaluation of severe abdominal blunt trauma than the multidisciplinary BP. Chest CT is a screening method for mediastinal hematoma but not for etiology.

Rupture of the gravid uterus secondary to motor vehicle trauma

A rare case of gravid uterine rupture secondary to motor vehicle accident trauma is presented. The case illustrates the serious risk to the fetus as well as the potential for maternal catastrophe with this condition. Normal physiological changes in pregnancy hinder the early diagnosis in many cases. A greater awareness of this entity along with prompt diagnosis, aggressive resuscitation, and surgical intervention will help reduce morbidity and mortality.

Blunt abdominal injuries. Diagnostic peritoneal lavage, ultrasonography and computed tomography scanning

The diagnosis of blunt abdominal injuries is one of the most difficult problems in the management of trauma. There is now better understanding of the diagnostic facilities available. Guidelines regarding the use of diagnostic peritoneal lavage, ultrasonography, or computed tomography scanning should be available in the Accident and Emergency department.

Blunt abdominal trauma

Assessment and management of patients with blunt abdominal trauma remains a challenge for emergency physicians. The spectrum of injury ranges from the trivial to the catastrophic and the initial assessment, resuscitation, and investigation of patients with abdominal trauma must be individualized. This article covers the important aspects of patient history and physical examination and addresses the relevant investigative tools available. An approach to the assessment of patients with abdominal trauma is provided; the goal is to diagnose significant injuries as soon as possible and avoid the pitfall of a delayed or missed diagnosis.

A prospective study of emergent abdominal sonography after blunt trauma

In North America, the role of emergent abdominal sonography [ultrasonography (US)] after blunt trauma requires further definition. The purpose of this prospective study was to compare US to the gold standards, diagnostic peritoneal lavage (DPL), and computed tomography (CT), in a population of adults after blunt trauma. In 206 adults who required either CT or DPL to assess possible abdominal injury, US was performed, before DPL or CT, and was aimed at the detection of intraperitoneal fluid. The mean Injury Severity Score and Glasgow Coma Scale score were 24.0 and 11.9, respectively. One hundred thirty-seven patients (67%) had CT and 69 (33%) had DPL. The positive and negative predictive values of US for intraperitoneal fluid were 90% and 97%, respectively. The sensitivity, specificity, and accuracy of US for free fluid were 81%, 98%, and 96%, respectively. Of the six false-negative USs, only one required surgery. The US examinations required 2.6 +/- 1.4 min. Emergent abdominal sonography is an accurate, rapid test for the presence of intraperitoneal fluid in adult blunt trauma victims and in these patients may prove valuable as a screening test for abdominal injury.

Quantitative sensitivity of ultrasound in detecting free intraperitoneal fluid

The minimum volume of intraperitoneal fluid that is detectable in Morison's pouch with ultrasound in the trauma setting is not well defined. To evaluate this question, we used diagnostic peritoneal lavage (DPL) as a model for intraperitoneal hemorrhage and undertook a blinded prospective study of the sensitivity of ultrasound in detecting intraperitoneal fluid. Participants included attending physicians and residents in emergency medicine, radiology, and surgery. During the infusion of the DPL fluid, participants continuously scanned Morison's pouch until they detected fluid. All participants were blinded to the rate of infusion and the volume infused. One hundred patients were entered into the study. The mean volume of fluid detected was 619 mL. Only 10% of participants detected fluid volumes less than 400 mL and the overall sensitivity at one liter was 97%. We conclude that reliable detection of intraperitoneal fluid in Morison's pouch requires a greater volume than has been previously described.

Elevated intracranial pressure masks hemorrhagic hypotension in a canine model

Previous clinical studies of blunt trauma patients with severe brain injuries have demonstrated that emergency department vital signs failed to consistently identify life-threatening abdominal injury. One hypothesis to explain this is that bradycardia and systemic hypertension from brainstem injury (the Cushing response) may mask the tachycardia and hypotension ordinarily manifested by hemorrhagic hypovolemia. This would result in inappropriately normal or near-normal emergency department vital signs for otherwise clinically apparent hypovolemia. To test this hypothesis, splenectomized dogs (n = 9) were phlebotomized to a systolic blood pressure (SBP) of 60 mm Hg. Subsequently, intracranial pressure (ICP) was artificially elevated in a controlled, incremental fashion. From a mean SBP of 58.4 +/- 3.9 mm Hg at a baseline ICP of 8.1 +/- 4.2 mm Hg, increases in ICP of only 20 mm Hg significantly raised SBP (in some animals). When ICP reached 70 mm Hg, mean SBP reached 95.1 +/- 8.7 mm Hg (p < 0.001) in spite of profound hemorrhagic hypovolemia. In all subjects, the tachycardia that accompanied hypovolemia tended towards normal with incremental increases in ICP. However, this did not reach statistical significance. In response to elevations in ICP, this hypovolemic canine model displayed normalization of SBP with variable changes in heart rate. These changes could mask hemorrhagic hypotension in humans sustaining multiple system trauma. These experimental data support clinical studies advocating immediate definitive abdominal evaluation in unconscious blunt trauma patients, regardless of vital signs.