Venous phase extravasation on computed tomography is a red flag sign in critical/severe pelvic injuries
Article information
Abstract
Purpose
Managing hemodynamically unstable patients with pelvic fractures is highly challenging, particularly when vascular injuries are present, as these can significantly worsen prognosis. This study evaluated outcomes in patients with pelvic trauma and vascular injuries prior to the introduction of preperitoneal pelvic packing.
Methods
We retrospectively reviewed the medical records of 195 patients with pelvic injuries who presented to the emergency room of our hospital between May 2003 and August 2013.
Results
Among the 195 patients, 34 had vascular injuries and 161 had nonvascular injuries. The vascular injury group had significantly higher transfusion rates (82.4% vs. 11.8%, P<0.001) and required a greater mean number of packed red blood cell units than the nonvascular group (5.2±5.5 vs. 0.4±1.4, P<0.001). Subgroup analysis within the vascular injury cohort revealed significant differences between patients with venous phase extravasation (n=5) and those with isolated arterial phase extravasation (n=29) in median packed red blood cell units transfused (12.5 units vs. 3 units; P=0.014), cardiac arrest rate (80.0% vs. 10.3%, P=0.003), and mortality rate (60.0% vs. 10.3%, P=0.029). Notably, patients with isolated venous extravasation showed a significantly higher mortality rate compared to those with isolated arterial extravasation (100% vs. 10.3%, P=0.004).
Conclusions
Venous phase extravasation was associated with higher transfusion requirements, cardiac arrest incidence, and mortality compared to arterial extravasation.
INTRODUCTION
Background
Pelvic trauma, most commonly resulting from blunt mechanisms, encompasses a spectrum of injuries ranging from minor, clinically insignificant fractures to life-threatening events that can lead to massive hemorrhage and death [1–5]. Uncontrolled pelvic bleeding due to vascular injury is a major cause of mortality in these patients [1–5]. Therefore, prompt and effective management is essential for hemodynamically unstable patients with pelvic trauma complicated by vascular injury.
Advancements in radiological imaging have enabled the rapid acquisition of computed tomography (CT) scans, allowing early identification of bleeding sources and timely initiation of interventions such as angioembolization, preperitoneal pelvic packing (PPP), and external fixation [6]. Despite these technological improvements, vascular injury remains the leading cause of death in blunt pelvic trauma [7]. Since the introduction of PPP, outcomes for hemodynamically unstable patients with pelvic fractures and vascular injuries have markedly improved [8]. However, no standardized treatment protocol has yet been established for vascular injuries detected on CT imaging.
Objectives
This study aimed to analyze outcomes in patients with pelvic trauma according to the presence of associated arterial or venous injuries.
METHODS
Ethics statement
This study was approved by the Institutional Review Board of Seoul National University Bundang Hospital (No. B-1502-286-105). The requirement for informed consent was waived due to the use of deidentified data and the retrospective nature of the study.
Study design and setting
We conducted a retrospective review of medical records for patients admitted to the emergency room (ER) of Seoul National University Bundang Hospital (Seongnam, Korea) between May 2003 and August 2013, before PPP implementation. Data from this period were analyzed to assess the risk and severity of pelvic injuries prior to PPP adoption.
This study specifically analyzed data from May 2003 to August 2013, before the widespread adoption of PPP. The focus on this pre-PPP era was intended to maintain data homogeneity and to isolate the prognostic effects of vascular injuries, particularly venous extravasation, without the confounding influence of modern interventions such as PPP, which have significantly altered treatment outcomes.
Participants
Of 202 patients with pelvic injuries, 7 were excluded due to multiple critical injuries, leaving 195 patients for analysis. Data collected included mechanism of injury, hemodynamic status, laboratory results, imaging findings, transfusion rates, transfusion volumes, and treatment outcomes.
Upon ER arrival, initial assessments were performed by emergency physicians. All patients with pelvic trauma underwent radiographic imaging and routine laboratory testing. CT was performed when internal organ injury, including pelvic injury, was suspected. When arterial phase extravasation was identified on CT, patients underwent conventional angiography followed by embolization. In cases of isolated venous phase extravasation, angiography was not performed, as it was considered ineffective. All patients with active bleeding received initial blood transfusions and pelvic binding compression.
Patients were classified into two groups: those with vascular injuries (extravasation) and those without. The vascular injury group was further subdivided into patients with isolated arterial injuries and those with combined iliac vein injuries. Arterial injury was defined as extravasation identified in the arterial phase of the initial CT or on conventional angiography, while venous injury was defined as extravasation observed in the venous phase of the initial CT (Fig. 1). Transfusion rates and the number of packed red blood cell (pRBC) units transfused during hospitalization (from ER arrival to discharge) were evaluated.
Extravasation on the venous phase of the initial computed tomography scan (arrow).
Statistical analysis
Results were expressed as means±standard deviation or as medians, as appropriate. Statistical analyses were performed using the Student t-test for continuous variables and the Pearson chi-square test or Fisher exact test for categorical variables, with PASW SPSS ver. 18.0 (SPSS Inc). A P-value of <0.05 was considered statistically significant.
RESULTS
Patient demographics
Among the 195 patients with pelvic trauma, 117 (60.0%) were male and the mean age was 49.1±22.9 years (Table 1). The primary mechanisms of injury were traffic accidents (n=104, 53.3%), slips (n=43, 22.0%), and falls (n=36, 18.5%). Treatment modalities included surgery (n=75, 38.5%), arterial embolization (n=29, 14.9%), conservative in-hospital management (n=37, 19.0%), and outpatient follow-up (n=77, 39.5%).
Patient demographics (n=195)
Comparison of patients with and without vascular injury
The nonvascular injury group consisted of 161 patients, while the vascular injury group comprised 34 patients. High-energy mechanisms of injury (e.g., traffic accidents and falls) were significantly more frequent in the vascular injury group than in the nonvascular group (68.3% vs. 91.2%, P=0.008).
Significant differences were also observed between the two groups in initial systolic blood pressure (132.2±26.8 mmHg vs. 111.3±36.3 mmHg, P<0.001), Injury Severity Score (16.0±0.8 vs. 29.2±5.7, P<0.001), transfusion rate (11.8% vs. 82.4%, P<0.001), number of pRBC units transfused (0.4±1.4 vs. 5.2±5.5, P<0.001), and mortality rate (0% vs. 17.6%, P<0.001) (Table 2).
Comparison of pelvic injuries with and without vascular injuries
Anatomic analysis of vascular injuries
The vascular injury group was further divided into patients with isolated arterial extravasation (n=29) and those with combined venous extravasation (n=5). The most frequently injured vessels were branches of the internal iliac artery (n=26, 76.4%), followed by the circumflex iliac artery (n=2, 8.2%) and the median sacral artery (n=1, 8.2%).
Management of bleeding
Arterial embolization was performed in 27 patients: unilateral internal iliac artery embolization in 10 patients (34.5%) and bilateral embolization in 15 patients (51.7%). No major ischemic complications of pelvic organs were reported, even among those who underwent bilateral embolization. Four patients with arterial injuries were treated conservatively with pelvic binding and resuscitation. Among the five patients with venous extravasation, one underwent PPP following cardiopulmonary resuscitation and arterial embolization and survived. Two patients received empirical arterial embolization of an internal iliac artery branch, and one underwent blind bedside resuscitative endovascular balloon occlusion of the aorta (REBOA) in the ER, which was ineffective, resulting in death. Two patients with venous injuries were managed conservatively, but both died (Table 3).
Management of hemorrhage
Subgroup analysis of the vascular injury group
Comparison between the isolated arterial extravasation group (n=29) and the combined iliac vein injury group (n=5) revealed significant differences in median pRBC units transfused (3 units vs. 12.5 units, P=0.014), cardiac arrest rate (10.3% vs. 80.0%, P=0.003), and mortality rate (10.3% vs. 60.0%, P=0.029) (Table 4). Further subdivision demonstrated that patients with isolated venous extravasation had a significantly higher mortality rate than those with isolated arterial extravasation (100% vs. 10.3%, P=0.004).
Comparison of the severity of arterial injuries and iliac vein injuries
DISCUSSION
This study is the first to demonstrate the prognostic significance of venous phase extravasation on CT scans compared with arterial extravasation in patients with pelvic trauma. Although less frequently studied, iliac vein injuries are known to be associated with poorer clinical outcomes [9–12].
Rapid CT scanning has become a routine component of ER evaluation owing to advances in imaging technology [6]. Although its use remains somewhat controversial, early CT imaging can accurately identify both the anatomic source and severity of injury [13]. Our findings indicate that high-energy trauma correlates with a higher incidence of vascular injury. Therefore, even in hemodynamically stable patients with high-energy trauma, CT should be performed promptly to identify potential bleeding sources.
All patients with vascular injuries in this study underwent CT imaging in the ER. Those with arterial phase extravasation were referred for emergency arterial embolization, and all survived following appropriate bleeding control and resuscitation. In contrast, patients with venous phase extravasation did not receive radiologic intervention, as such procedures were considered ineffective at the time. Before PPP was introduced, there was no consensus on the optimal management of venous hemorrhage in pelvic trauma [8]. Major iliac vein injuries with venous extravasation visible on CT are life-threatening, often necessitating massive transfusion and rapid hemostatic control. Conservative management strategies, such as fluid resuscitation and pelvic binding, were associated with extremely high mortality, and only a few patients survived [9–12].
Recognizing major venous injuries is essential for surgical preparedness and appropriate intervention. Failure to anticipate massive bleeding from venous injury often leads to a poor prognosis. Kataoka et al. reported favorable outcomes with stent placement after rapid venography in patients with hemorrhagic shock due to pelvic trauma [9]. However, endovascular management requires preparation time and may not be suitable for hemodynamically unstable patients. Thus, the role of endovascular therapy in iliac vein injury remains controversial, and further high-quality research is warranted [9–12].
Recent studies have shown promising outcomes for hemodynamically unstable patients treated with PPP [14–16]. PPP provides rapid pelvic hemorrhage control and can reduce the need for emergency angiography. It also significantly decreases blood product requirements and has been associated with reduced mortality in unstable patients [14–16]. PPP is particularly effective for suspected major venous bleeding because it compresses venous structures more effectively than arterial ones. Since its widespread adoption, PPP has been employed in hemodynamically unstable patients with pelvic fractures exhibiting hemorrhage, hematoma, extravasation, or ambiguous findings, resulting in decreased vasopressor use and reduced transfusion needs [14–16].
This study underscores the importance of early PPP intervention for patients with venous extravasation by providing data from the pre-PPP era. It further highlights the need to recognize venous bleeding, which is often overlooked, to inform timely and appropriate clinical decisions.
Based on previous treatment protocols [17,18] and our current findings, we propose an updated management algorithm emphasizing anatomic factors (Fig. 2). Given the higher transfusion requirements and worse outcomes observed in pelvic venous extravasation, urgent management is warranted when iliac vein extravasation is detected on CT. While arterial embolization remains the treatment of choice for arterial injury, patients with venous phase extravasation should undergo preparation for massive transfusion and PPP [19]. If feasible, venography followed by stent grafting may also be considered [10].
Proposed updated protocol for the management of hemodynamically unstable pelvic injury, integrating the finding that venous extravasation is a critical “red flag” sign that requires prompt and aggressive management. CT, computed tomography.
Limitations
This study has several limitations. First, its retrospective design and relatively small sample size, especially the small subgroup of five patients with venous extravasation, limit the statistical power of our comparisons. Although the association between venous extravasation and poor outcomes was statistically significant, larger prospective studies are needed to validate these results. Second, the study period (2003–2013) predates the routine use of modern management approaches such as PPP and REBOA. Nonetheless, this historical context adds value, as it underscores the clinical significance of these modern interventions. The high mortality (60%) and cardiac arrest (80%) rates among patients with venous extravasation demonstrate the severe nature of these injuries and strongly support the need for rapid, aggressive interventions in current trauma practice.
Although data from the pre-PPP era may appear outdated, our findings are fundamental for understanding the evolution of pelvic trauma management. This study establishes venous extravasation as a critical “red flag” finding on CT imaging. Even in contemporary multidisciplinary trauma care, detecting this sign should immediately trigger consideration of massive transfusion protocols and urgent interventions such as PPP or REBOA. The outcomes from this historical cohort provide a compelling reminder of the high mortality risk associated with venous extravasation and reinforce the necessity of modern, aggressive treatment protocols.
Conclusions
Patients with pelvic fractures and vascular injuries presented with lower initial systolic blood pressure, higher transfusion rates, greater pRBC requirements, and higher mortality than those without vascular injuries. Subgroup analysis demonstrated that patients with combined iliac vein injuries required more transfusions and had higher rates of cardiac arrest and mortality compared to those with isolated arterial injuries. Isolated iliac vein injuries were also associated with markedly higher mortality than isolated arterial injuries.
Notes
Author contributions
Conceptualization: HKS; Formal analysis: MJC; Investigation: MJC; Methodology: HKS, CI, HRS; Resources: JWW; Supervision: JWW; Writing–original draft: CI; Writing–review & editing: all authors. All authors read and approved the final manuscript.
Conflicts of interest
The authors have no conflicts of interest to declare.
Funding
The authors received no financial support for this study.
Data availability
Data analyzed in this study are available from the corresponding author upon reasonable request.