Diagnostic Peritoneal Lavage for Diagnosing Blunt Hollow Visceral Injury: The Accuracy of Two Different Criteria and Their Combination

Nonsurgical management of traumatic pneumoperitoneum in a cat

OBJECTIVE

To describe the nonsurgical management of a cat with traumatic pneumoperitoneum.

CASE SERIES SUMMARY

A 4-year-old cat was presented following vehicular polytrauma. Thoracic radiographs revealed 4 rib fractures, a scapular fracture, and pneumothorax. Abdominal ultrasound revealed a small volume of free abdominal fluid. Computed tomography showed a mild pneumoretroperitoneum and a pneumoperitoneum in the region of the porta hepatis. The cat was managed conservatively with close monitoring. Exploratory laparotomy was not pursued given patient stability and static serial imaging studies revealing no indications for surgical intervention. After 6 days, the pneumoperitoneum was no longer detectable.

NEW OR UNIQUE INFORMATION PROVIDED

To the authors' knowledge, this is the first report of successful nonsurgical management of traumatic pneumoperitoneum in a cat.

CT scan and Diagnostic Peritoneal Lavage: towards a better diagnosis in the area of nonoperative management of blunt abdominal trauma

BACKGROUND

The diagnosis of small bowel and mesenteric injuries (BBMI) after blunt abdominal trauma remains difficult, which results in delayed treatment and increased mortality and morbidity. Diagnostic peritoneal lavage (DPL) in patients with 1 or 2 abnormal CT findings that are suggestive of BBMI was proposed, but the rate of unnecessary surgical exploration remains high.

PATIENTS AND METHODS

Blunt abdominal trauma patients with 1 or 2 CT findings predictive of BBMI from 2001 to 2014 underwent a DPL with calculation of a cell count ratio (CCR) dividing the ratio of white blood cells (WBCs) to red blood cells (RBCs) (WBC/RBC ratio) in the lavage fluid by the WBC/RBC ratio in peripheral blood. Surgical exploration of the abdomen was performed immediately in cases with a CCR≥1. CT findings, DPL and surgery results, and global outcome were analyzed.

RESULTS

Thirty-seven were included in the study (27 males, median age of 30 years (range, 17-69 years)). Exploratory laparotomy was performed in 24 patients (65%). Sixteen patients (67%) had BBMI: 7 hollow organ perforations or tears (29%), including 4 bowel resection with primary anastomosis and 3 single sutures, and 9 patients had mesenteric injuries. CT findings associated with BBMI and hollow organ perforation were large peritoneal effusion (p=0.02) and small bowel wall abnormalities (p=0.002). No postoperative complications were observed. Sensitivity and specificity of DPL for the diagnosis of bowel injuries were respectively 100% (CI 95% [59-100]) and 43% (CI 95% [25-63]). The sensitivity remained 100% (CI 95% [59-100]) when the ratio was ≥4 (n=10 patients), and the specificity reached 90% (CI 95% [73-98]).

CONCLUSION

DPL is sensitive for the diagnosis of BBMI in stable trauma patients with 1 or 2 unexplained CT abnormalities, but specificity is low with a high rate of nontherapeutic laparotomy in case of CCR≥1. Indications for exploratory laparotomy could be restricted to patients with a CCR≥4 to improve the specificity of diagnosis management.

Hollow viscus injury

BACKGROUND

Hollow viscus injuries are uncommon and occur in approximately 1% of all blunt trauma patients.

DISCUSSION

These injuries are often not suspected and are difficult to diagnosis. Morbidity and mortality are high, and a negative abdominal computed tomography is not sufficient to rule out these injuries in certain clinical scenarios.

CONCLUSION

Using a case-based approach, the epidemiology and diagnostic pathways to manage hollow viscus injuries are reviewed.

A multi-dimensional approach for describing internal bleeding in an artery: implications for Doppler ultrasound guiding HIFU hemostasis

Doppler ultrasound has shown promise in detecting and localizing internal bleeding. A mathematical approach was developed to describe the internal bleeding of the injured artery surrounded by tissue. This approach consisted of a two-dimensional (2D) model describing the injured vessel and a one-dimensional model (1D) mimicking the downstream of the vessel system. The validity of this approach was confirmed by both the numerical simulation and in vivo measurement of a normal porcine femoral artery. Furthermore, the artery was injured using a 16-gauge needle to model a penetrating injury. The velocity waveform at the puncture site was modeled and compared with those at the upstream and downstream of the artery. The results demonstrated that there was a significant increase in magnitude and a phase lag for the peak systolic velocity at the injury site. These results were qualitatively in agreement with the in vivo experiment. Flow turbulence indicated by this approach was also observed in a color Doppler image in the form of a checkered color pattern. This approach might be useful for quantitative internal bleeding detection and localization. Also, the phase lag of the peak systolic velocity was indicated to be potential in the application of internal bleeding detection.

Hemorrhage control using high intensity focused ultrasound

Hemorrhage control is a high priority task in advanced trauma care, because hemorrhagic shock can result in less than a minute in cases of severe injuries. Hemorrhage was found to be solely responsible for 40-50% of traumatic civilian and battlefield deaths in recent years. The majority of these deaths were due to abdominal and pelvic injuries with hidden and inaccessible bleeding of solid organs such as liver, spleen, and kidneys, as well as major blood vessels. High intensity focused ultrasound (HIFU) offers a promising method for hemorrhage control. An important advantage of HIFU is that it can deliver energy to deep regions of tissue where hemorrhage is occurring, allowing cauterization at depth of parenchymal tissues, or in difficult-to-access anatomical regions, while causing no or minimal biological effects in the intervening and surrounding tissues. Moreover, HIFU can cause both thermal and mechanical effects that are shown to work synergistically for rapid hemorrhage control. The major challenges of this method are in development of bleeding detection techniques for accurate localization of the injury sites, delivery of large HIFU doses for profuse bleeding cases, and ensuring safety when critical structures are in the vicinity of the injury. Future developments of acoustic hemostasis technology are anticipated to be for applications in peripheral vascular injuries where an acoustic window is usually available, and for applications in the operating room on exposed organs.

Detection of bleeding in injured femoral arteries with contrast-enhanced sonography

OBJECTIVE

The purpose of this study was to investigate the feasibility of detecting acute arterial bleeding by means of contrast-enhanced sonography.

METHODS

Puncture injury was produced transcutaneously with an 18-gauge needle in 26 femoral arteries (13 in the control group and 13 in the contrast-enhanced group) of rabbits. A sonographic contrast agent (Optison; Mallinckrodt Inc, St Louis, MO) was administered intravenously at a dose of 0.06 to 0.07 mL/kg. Sonography of the femoral arteries was performed before and after injury, both before and after injection of Optison, with B-mode imaging, color Doppler imaging, and pulse inversion harmonic imaging (PIHI).

RESULTS

The specific location of active bleeding could not be visualized in B-mode and PIHI scans in the control group (no Optison injection). After administration of Optison, the bleeding site was visualized because of the increased echogenicity of the extravasated blood at the puncture site in both B-mode imaging and PIHI. In color Doppler images, bleeding sites were localized successfully in 84.6% of the cases in the presence of Optison and in 30.8% of the cases without Optison. Histologic examination (light microscopy) of the hematoma confirmed the presence of contrast agent microbubbles in the extravascular space surrounding the artery.

CONCLUSIONS

Contrast-enhanced sonography may provide an effective method for detecting arterial bleeding.