REBOA for the IVC? Resuscitative balloon occlusion of the inferior vena cava (REBOVC) to abate massive hemorrhage in retrohepatic vena cava injuries.

BACKGROUND: The use of resuscitative endovascular balloon occlusion as a maneuver for occlusion of the aorta is well described. This technique has life-saving potential in other cases of traumatic hemorrhage. Retrohepatic inferior vena cava (IVC) injuries have a high rate of mortality, in part, due to the difficulty in achieving total vascular isolation. The purpose of this study was to investigate the ability of resuscitative balloon occlusion of the IVC to control suprahepatic IVC hemorrhage in a swine model of trauma. METHODS: Thirteen swine were randomly assigned to control (seven animals) versus intervention (six animals). In both groups, an injury was created to the IVC. Hepatic inflow control was obtained via clamping of the hepatoduodenal ligament and infrahepatic IVC. In the intervention group, suprahepatic IVC control was obtained via a resuscitative balloon occlusion of the IVC placed through the femoral vein. In the control group, no suprahepatic IVC control was established. Vital signs, arterial blood gases, and lactate were monitored until death. Primary end points were blood loss and time to death. Lactate, pH, and vital signs were secondary end points. Groups were compared using the χ and the Student t test with significance at p < 0.05. RESULTS: Intervention group's time to death was significantly prolonged: 59.3 ± 1.6 versus 33.4 ± 12.0 minutes (p = 0.001); and total blood loss was significantly reduced: 333 ± 122 vs 1,701 ± 358 mL (p = 0.001). In the intervention group, five of the six swine (83.3%) were alive at 1 hour compared to zero of seven (0%) in the control group (p = 0.002). There was a trend toward worsening acidosis, hypothermia, elevated lactate, and hemodynamic instability in the control group. CONCLUSIONS: Resuscitative balloon occlusion of the IVC demonstrates superior hemorrhage control and prolonged time to death in a swine model of liver hemorrhage. This technique may be considered as an adjunct to total hepatic vascular isolation in severe liver hemorrhage and could provide additional time needed for definitive repair. LEVEL OF EVIDENCE: Therapeutic study, level II.

Therapeutic Anticoagulation for Isolated Calf Deep Vein Thrombosis.

IMPORTANCE: Deep vein thrombosis (DVT) isolated to the calf veins (distal to the popliteal vein) is frequently detected with duplex ultrasonography and may result in proximal thrombosis or pulmonary embolism (PE). OBJECTIVE: To evaluate whether therapeutic anticoagulation is associated with a decreased risk for proximal DVT or PE after diagnosis of an isolated calf DVT. DESIGN, SETTING, AND PARTICIPANTS: All adult patients with ultrasonographic detection of an isolated calf DVT from January 1, 2010, to December 31, 2013, at the Vascular Laboratory of the University of California, Davis, Medical Center were included. Patients already receiving therapeutic anticoagulation and those with a chronic calf DVT, a contraindication to anticoagulation, prior venous thromboembolism within 180 days, or diagnosis of a PE suspected at the time of calf DVT diagnosis were excluded. Data were analyzed from August 18, 2015, to February 14, 2016. EXPOSURES: Intention to administer therapeutic anticoagulation. MAIN OUTCOMES AND MEASURES: Proximal DVT or PE within 180 days of the diagnosis of the isolated calf DVT. RESULTS: From 14 056 lower-extremity venous duplex studies, we identified 697 patients with an isolated calf DVT and excluded 313 of these. The remaining 384 patients were available for analysis (222 men [57.8%]; 162 women [42.2%]; mean [SD] age, 60 [16] years). The calf DVT involved an axial vein (anterior tibial, posterior tibial, or peroneal) in 243 patients (63.2%) and a muscular branch (soleus or gastrocnemius) in 215 (56.0%). Physicians attempted to administer therapeutic anticoagulation in 243 patients (63.3%), leaving 141 control participants. Proximal DVT occurred in 7 controls (5.0%) and 4 anticoagulation recipients (1.6%); PE, in 6 controls (4.3%) and 4 anticoagulation recipients (1.6%). Therapeutic anticoagulation was associated with a decreased risk for proximal DVT or PE at 180 days (odds ratio [OR], 0.34; 95% CI, 0.14-0.83) but an increased risk for bleeding (OR, 4.35; 95% CI, 1.27-14.9), findings that persisted after adjustment for confounding factors (ORs, 0.33 [95% CI, 0.12-0.87] and 4.87 [95% CI, 1.37-17.3], respectively) and sensitivity analyses. CONCLUSIONS AND RELEVANCE: Rates of proximal DVT or PE are low after isolated calf DVT. Therapeutic anticoagulation is associated with a reduction of these outcomes but an increase in bleeding.