2013 Scholarship Winners
Grand Prize Winner
Arterial Versus Venous Fluid Resuscitation; Restoring Cardiac Contractions in Cardiac Arrest Following Exsanguinations
Alireza Hamidian Jahromi, MD
General Surgery Resident, Department of Surgery, Louisiana State University Health Sciences Center, Shreveport, LA
Purpose: We hypothesized that intra-arterial (IA) fluid resuscitation is more effective than intravenous (IV) resuscitation in restoring cardiac contractions of cardiac-arrested mice following severe hemorrhagic shock.
Methods: Mice (N=22) were anesthetized using ketamine/xylazine. Arterial and venous systems accessed through cannulation of the carotid artery and the Jugular vein, respectively. As much blood as possible was aspirated from the carotid artery access. Mice were observed until the complete cessation of chest wall motions. Following 30 seconds delay, IV (N=5) and IA access (N=6) were used for fluid resuscitation using Ringer Lactate (RL) in a similar volume to the aspirated blood. Mice were observed for restoration of chest wall motions. In phase-II of the study, after cessation of chest motions, mice (N=11) underwent a thoracotomy and cardiac contractions were observed. In three mice, IV RL Infusion after cardiac arrest failed to restore cardiac contractions and was followed by IA RL infusion. In eight mice, following cardiac arrest intermittent IA RL infusion was performed.
Results: While IV RL Infusion failed to restore chest motion in mice (N=6), IA RL infusion restored chest motion in all mice examined (N=5) (p= 0.0067). In three mice, IV RL infusion after cardiac arrest showed no effect on cardiac contractions. After failure of venous infusion, IA RL infusion was performed which resulted in restoration of cardiac contractions for 13.33+1.76 minutes. In eight mice, intermittent IA infusion of RL after cardiac arrest, sustained cardiac contractions for 31.43 + 10.9 minutes (P= 0.017).
Conclusion: Intra-arterial fluid resuscitation is superior to IV resuscitation in hemorrhagic shock induced cardiac arrest.
A True Orthotopic Gastric Cancer Murine Model Using Electrocoagulation
Jasneet S. Bhullar, MD
Surgery Resident, Providence Hospital & Medical Centers, Southfield, MI
Purpose: Orthotopic mouse models of human gastric cancer represent an important in vivo tool for testing chemotherapeutic agents and for studying intraluminal factors. Currently, orthotopic mouse models of gastric cancer require an operative procedure involving either injection or implantation of tumor cells in stomach layers. The resultant tumor does not grow from the stomach’s mucosal surface; thus, it does not mimic the human disease process.
Methods: A low-dose gastric mucosal coagulation was done transorally in the body of stomach using a specially designed polyethylene catheter in 16 female SCID mice. This was followed by the instillation of SNU-16 human gastric cancer tumor cells (1x10 6 cells). Five mice each were euthanized at 1 and 2 months, and 6 mice were euthanized at 3 months.Three control mice underwent electrocoagulation alone and three mice underwent cell line instillation alone.
Results: Tumors were detected in 11/16 experimental mice but not in the control mice. Tumors were noted in mice at 1 month. Over time, there was an increase in tumor growth and metastasis to lymph nodes and surrounding organs. Histopathological evaluation showed that the tumors grew from the gastric mucosa.
Conclusion: Our model is minimally invasive, easy to create, and overcomes the limitations of the existing models as the tumor arises from the stomach’s mucosal layer, while mimicking the human disease in terms of morphology and biological behavior. This is the first report of a true orthotopic gastric cancer murine model. This model opens new doors for further studies which were not possible earlier.
Comparison of Mammographically and Self-Detected New Breast Lesions at a Community Breast Cancer Center
Thomas D. Willson, MD
Resident, Saint Joseph Hospital,Chicago, IL
Purpose: Breast self-examination (BSE) has been widely recommended for more than 70 years despite a lack of data supporting the practice. In 2009, the United States Preventive Services Task Force issued new guidelines including a recommendation against teaching women BSE. This study was performed to elucidate yield of BSE in terms of new malignancies discovered.
Methods: A total of 389 patients presenting for breast complaints between January 2009 and December 2011 at St. Joseph Hospital in Chicago, IL USA were reviewed retrospectively. Of these, 113 were follow-up visits, 12 were men, and 26 were lost to follow up. The remaining 238 comprised a cohort of women with new breast complaints over the three-year period. Records were reviewed for demographics, method of initial diagnosis, BIRADS score, and final diagnosis.
Results: Lesions were identified by mammography in 117 patients (49.2%), by self-examination in 113 patients (47.5%) and by other methods in 8 patients (3.4%). Of these lesions, 109 were malignant with 52.3% mammographically identified. Patients with self-identified lesions were younger, but there was no statistical difference in BIRADS score between self-identified and mammographically identified lesions, nor between lesions requiring operation in either group. The BIRADS score was statistically different in patients with self-detected lesions who underwent surgery versus those who did not (3.8 vs 3.3, p=0.00047), suggesting that patients are open to their surgeons’ recommended management.
Conclusion: Although prior studies have failed to demonstrate reductions in overall mortality from BSE, this study demonstrates that BSE is an effective method for detecting breast cancers. Physicians should encourage breast self-examination at all ages and at minimum refer women who detect unexplained cystic or solid lesions for imaging and perform biopsies when indicated.