2015 Scholarship Winners
JASNEET S. BHULLAR, MD, FICS(J), Chief Resident, Department of Surgery. Providence Hospital & Medical Centers, Southfield, MI
Novel Concept of Electrocoagulation & Pancreatic Tumor Cell Implantation: Creation of Minimally Invasive Orthotopic Murine Model of Pancreatic Cancer
PURPOSE: Orthotopic murine models of pancreatic cancer represent an important tool for evaluating treatment strategies. Several genetically modified mouse tumors and xenograft models have been reported. Genetic models have unpredictable growth & variable waiting period, while orthotopic models are operative ones, difficult to create and result in irregular metastasis. There is a constant endeavor to create an orthotopic model which replicates the human disease process.
METHODS: Orthotopic pancreatic tumors were induced in 20 SCID mice using a novel technique. Low dose electrocoagulation of pancreas under laparoscopic guidance (using Coloview-mouse colonoscope) with thin electrode, followed by injection of 106 BxPC3 pancreatic cancer cells was done (n=12, study group). Control mice underwent electrocoagulation alone (n=4, group 1) and tumor cell injection alone (n=4, group 2). Mice were evaluated for tumor growth and metastasis by necropsy (4 and 8 week for experimental group; 8 weeks for control group).
RESULTS: Tumors were detected in 11/12 mice in experimental group, 1/4 in control group 2, and none in control group 1. Over time there was an increase in tumor growth, tumor volume, lymphovascular invasion of pancreas, with metastasis to lymph nodes and surrounding organs. The tumor was replicative of the human disease process in terms of growth and metastasis.
CONCLUSIONS: We report a novel concept of tumor cell implantation at site of electrocoagulation of pancreas. Combined with the minimally invasive technique, yields a replicative orthotopic murine model of pancreatic cancer. Our model is minimally invasive, easy to create, and overcomes the limitations of the existing models while questions the possibility free floating tumor cell implantation at resection site.
ALIREZA HAMIDIAN JAHROMI, MD, FICS, General Surgery Resident (PGY-III), Louisiana State University Health Center, Shreveport, LA
Evaluation of Urine Fibrinogen Level in a Murine Model of Contrast Induced Nephropathy
PURPOSE: Urinary fibrinogen (UFg) has been proposed as a biomarker for kidney injuries caused by ischemia/reperfusion and cisplatin toxicity. We investigated whether UFg could also be a potential biomarker for contrast-induced nephropathy (CIN).
METHODS: To create a CIN model, mice received a prostaglandin synthesis inhibitor (indomethacin) and a nitric oxide synthase inhibitor (Nω-Nitro-L-arginine methyl ester) intraperitoneally followed by Iodixanol (6.24 and 12.48 g iodine/ml in low-dose and high-dose groups). In the control group, normal saline was administered instead of Iodixanol. Urine/blood samples were collected for UFg and serum creatinine (SCr) analysis using ELISA. Kidneys were harvested 24 hours after contrast injection to quantify Fg RNA and protein expressions using qRT-PCR and Western blot (WB) and for histopathological examination.
ESULTS: Histopathological examination demonstrated mild renal injury in the low-dose group, and moderate renal injury in the high-dose group. UFg levels were 0.37±0.13 µg/mg-Cr in the control group, 3.46±2.89 µg/mg-Cr in the low-dose group (P<0.05).
CONCLUSIONS: Increased UFg levels were consistent with the pathological severities of CIN in a murine model. We propose that UFg could be used as a potential biomarker for early CIN diagnosis.
ANAND TARPARA, MD, PGY-1 Resident, General Surgery, Texas Tech University Health Sciences Center School of Medicine, Lubbock, TX
Coil Embolization of Superior Gluteal Artery Tear through Ipsilateral Popliteal Artery: A Unique Approach
PURPOSE: We report a unique approach to successfully coil embolize iatrogenic injury to the superior gluteal artery intra-operatively through popliteal artery. Our case report involved a forty-five year-old male involved in a motor vehicle collision, where he was t-boned on driver side. His relevant injuries include a left iliac wing fracture, superior and inferior pelvic rami fractures, acetabular fracture, and dislocated sacroiliac joint.
METHODS: Perform a literature review on traumatic/iatrogenic injury to superior gluteal artery and review management strategies. Describe our approach to successfully coil embolize the left gluteal artery injury confirmed on subsequent left pelvic angiogram. Left popliteal artery retrograde catheterization was performed using a 5Fr angle glide catheter. Pelvic angiogram was captured intra-operatively while patient remained in prone position using a 5Fr Simmons one catheter. Ipsilateral 2nd order gluteal artery catheterization was achieved and three 5mm x 15mm coils were deployed at the affected site.
RESULTS: To the best of our knowledge, there is no description of a popliteal artery approach to successfully coil embolize the gluteal artery or associated branches. A review of the literature reveals superior gluteal artery injury is well documented in literature with several etiologies including iatrogenic, traumatic penetrating injury, traumatic blunt injury, and gluteal aneurysms. One case report that describes traumatic superior gluteal artery injury secondary to sacral fracture, which was successfully coil embolized without mention of technique/approach.
CONCLUSIONS: Classic approach to this injury is usually done in supine position with access from the contralateral femoral artery. However, due to the nature of our patient’s injury and risk of contamination of an exposed wound, we executed our coil embolization of the superior gluteal artery tear through an ipsilateral popliteal artery approach in prone position. This demonstrates a unique approach not previously described in literature.
MARK WEISMILLER, MD, Surgery Resident, Providence Hospital and Medical Centers, Southfield, MI
Risk Factor Identification for Postoperative Groin Incision Complications and Recommendations on Treatment
PURPOSE: Complications involving groin incisions, particularly those made for vascular interventions, pose a common and often times challenging hurdle in the management of the postoperative patient. The objective of this study is to both identify risk factors that predispose to these complications, as well as provide recommendations on treating these complications.
METHODS: Using ICD-9 codes, patients were identified who incurred a hematoma, lymphocele, wound infection or fascial dehiscence related to a groin incision for a vascular procedure over a 5 year period. Charts were reviewed and assessed for risk factors, complication type, and treatment variables.
RESULTS: One hudred charts qualified for the study. A history of diabetes mellitus was found in 46. Daily steroid use was observed in 5 of the 8 lymphoceles identified, and non-vertical incisions were associated with 7 of the 8. Prolonged surgery (> 4 hours) was seen in 26 cases, and antibiotics were re-dosed intraoperatively in 9 of these cases. In all 9 of these cases the complication was hematoma. Of the remaining 17 cases hematoma represented 7 while wound infection and fascial dehiscence made up 3 and 7 respectively, suggesting that appropriate re-dosing of antibiotics is protective not only against infection but also wound dehiscence. The most common complication was hematoma at 79. Observation was sufficient to successfully manage 46. The remaining 33 required evacuation. Reasons to evacuate included a pulsatile or expanding hematoma, the need for systemic anticoagulation, and concomitant infection or wound dehiscence. Six of the eight lymphoceles required ligation of the problematic duct. Fascial dehiscence was treated with open repair in all 13 of the cases found, often times necessitating a muscle flap and negative pressure therapy. For the 18 wound infections discovered, 17 required operative debridement with or without negative pressure therapy.
CONCLUSIONS: Conservative management should be instituted whenever possible to treat postoperative groin hematomas, reserving evacuation for complicated hematomas. Furthermore, careful observation is by and large inadequate to treat lymphoceles, wound infections and fascial dehiscence, and we recommend early operative intervention for such complications with consideration for negative pressure dressing therapy thereafter.