The effect of metallic tracheal stents on radiation dose in the airway and surrounding tissues

Background

Metallic airway stents are often used in the management of central airway malignancies. The presence of a metallic foreign body may affect radiation dose in tissue. We studied the effect of a metallic airway stent on radiation dose delivery in a phantom and an in vivo porcine model.

Methods

A metallic tracheal stent was fitted onto a support in a water phantom. Point dosimeters were positioned in the phantom around the support and the stent. Irradiation was then performed on a linear accelerator with and without the stent. Metallic tracheal stents were deployed in the trachea of three pigs. Dosimeters were implanted in the tissues near (Group 1) and away (Group 2) from the stent. The pigs were then irradiated, and the dose perturbation factor was calculated by comparing the actual dose detected by the dosimeters versus the planned dose.

Results

The difference in the dose detected by the dosimeters and the planned dose ranged from 1.8% to 6.1% for the phantom with the stent and 0%–5.3% for the phantom without the stent. These values were largely within the manufacturer's specified error of 5%. No significant difference was observed in the dose perturbation factor for Group 1 and Group 2 dosimeters (0.836 ± 0.058 versus 0.877 ± 0.088, P = 0.220) in all the three pigs.

Conclusions

Metallic airway stents do not significantly affect radiation dose in the airway and surrounding tissues in a phantom and porcine model. Radiation treatment planning systems can account for the presence of the stent. External beam radiation can be delivered without concern for significant dose perturbation.     

Inhibition of AAA in a rat model by treatment with ACEI perindopril

Background

The purpose of the present study was to evaluate the effect of a new angiotensin converting enzyme inhibitor perindopril on the formation of experimental abdominal aortic aneurysms (AAAs) in a rat model induced by intraluminal elastase infusion and extraluminal calcium chloride (CaCl₂) application.

Materials and methods

Thirty-six male Sprague–Dawley rats were randomly distributed into three groups (n = 12 per group): model (A), sham (B), and perindopril (C). Rats in model and perindopril groups underwent intra-aortic elastase perfusion and extraluminal CaCl₂ application to induce AAAs. Rats in the sham group received aortic perfusion and extraluminal application of saline. A dose of 3 mg/kg/d of perindopril was fed orally in the perindopril group. The maximum abdominal aortic diameter was measured in vivo on days 0 and 28 and by ultrasound on days 7, 14, and 21. The arterial blood pressure was measured directly using a pressure transducer after cannulation in surgery and before death. AAA tissue samples were harvested at day 28 and evaluated using normal hematoxylin and eosin stain, Verhoeff-van Gieson stain for elastin, and image analysis technique.

Results

Aortic diameters of rats in the model group consistently increased within 28 d, coinciding with the development of a transmural inflammatory response, thickening of intima, and destruction of the elastic media. Without alteration in blood pressure, the AAA formation rate and mean maximal diameter of aorta at day 28 were significantly lower in the perindopril group compared with the control group (1.71 ± 0.20 versus 2.70 ± 0.69 mm, P < 0.001; 0% versus 90.91%, P < 0.001) and were similar to those in the sham group (1.79 ± 0.29 mm, P = 0.175; 0%, P = 1). The thickness of intima in the perindopril group was lower than that in the model group (20.68 ± 9.96 versus 58.49 ± 32.01 μm, P = 0.001), but higher than that in the sham group (7.23 ± 2.68 μm, P = 0.005). The intensity of elastin fiber showed the opposite trend (0.8541 ± 0.0495 in sham group versus 0.7376 ± 0.1024 in perindopril group versus 0.5413 ± 0.0912 in model group, P < 0.001).

Conclusions

Perindopril inhibited the aortic degeneration and AAA formation in the experimental AAA model induced by elastase and CaCl₂. This effect, which was independent of its influence on hemodynamics, appeared to be induced by the suppression of the inflammatory cell influx and intimal thickening and the preservation of aortic medial elastin.     

Clinical outcomes after separate and composite replacement of the aortic valve and ascending aorta

Objectives

We sought to compare the clinical profile and outcomes of operations for aortic valve disease and ascending aortic aneurysm in patients treated with aortic valve replacement and supracoronary replacement of the ascending aorta or composite replacement of the aortic valve and ascending aorta (Bentall operation).

Methods

From 1990 through 2001, 133 patients had aortic valve replacement and supracoronary replacement of the ascending aorta, and 452 patients had Bentall operations. Aortic valve replacement and supracoronary replacement of the ascending aorta was performed in patients who had aortic valve disease and dilation of the ascending aorta, whereas the Bentall operation was performed in patients with aortic root abnormality and ascending aortic aneurysm. Mean follow-up was 4.6 ± 3.1 years and was 100% complete.

Results

Patients who had aortic valve replacement and supracoronary replacement of the ascending aorta were older (61 ± 13 vs 52 ± 16 years, P < .001) and more likely to have aortic stenosis, coronary artery disease, and mitral valve disease than those who had Bentall operations. The use of mechanical valves was equal in both groups (42% for aortic valve replacement and supracoronary replacement of the ascending aorta and 43% for the Bentall operation). Operative mortality was 5% for patients undergoing aortic valve replacement and supracoronary replacement of the ascending aorta and 4% for patients undergoing the Bentall operation (P = .45). Survival at 10 years was 57% ± 8% for patients undergoing aortic valve replacement and supracoronary replacement of the ascending aorta and 74% ± 4% for patients undergoing the Bentall operation (P = .04), but the type of operation had no effect on survival. Older age, moderate or severe left ventricular dysfunction, active endocarditis, previous cardiac surgery, and coronary artery disease were independent predictors of death. The freedom from reoperation at 10 years was 95% ± 5% for patients undergoing aortic valve replacement and supracoronary replacement of the ascending aorta and 94% ± 3% for patients undergoing the Bentall operation (P = .18). Reoperations were mostly because of tissue valve failure or endocarditis. The risk of valve-related complications was the same in both groups. No patient required reoperation for aortic root aneurysm after having aortic valve replacement and supracoronary replacement of the ascending aorta.

Conclusions

Aortic valve replacement and supracoronary replacement of the ascending aorta and the Bentall operation provide comparable long-term results. The Bentall operation is more appropriate for patients with aortic root abnormality and a dilated ascending aorta, whereas aortic valve replacement and supracoronary replacement of the ascending aorta is a perfectly acceptable operation for patients with aortic valve disease, normal or mildly dilated aortic sinuses, and a dilated ascending aorta.     

Diabetes remission and glycemic response to pre-bariatric surgery diet

Background

Before bariatric surgery, some patients with type 2 diabetes mellitus (T2DM) experience improvement in blood glucose control and reduced insulin requirements while on a preoperative low-calorie diet (LCD). We hypothesized that patients who exhibit a significant glycemic response to this diet are more likely to experience remission of their diabetes in the postoperative period.

Materials and methods

Insulin-dependent T2DM patients undergoing bariatric surgery between August 2006 and February 2011 were eligible for inclusion. Insulin requirements at day 0 and 10 of the LCD were compared. Patients with a ≥50% reduction in total insulin dosage to maintain appropriate blood glucose control were considered rapid responders to the preoperative LCD. All others were non–rapid responders. We analyzed T2DM remission rates up to 1 y postoperatively.

Results

A total of 51 patients met inclusion criteria and 29 were categorized as rapid responders (57%). The remaining 22 were considered non–rapid responders (43%). The two groups did not differ demographically. Rapid responders had greater T2DM remission rates at 6 (44% versus 13.6%; P = 0.02) and 12 mo (72.7% versus 5.9%; P < 0.01). In patients undergoing laparoscopic gastric bypass, rapid responders showed greater excess weight loss at 3 mo (40.1% versus 28.2%; P < 0.01), 6 mo (55.2% versus 40.2%; P < 0.01), and 12 mo (67.7% versus 47.3%; P < 0.01).

Conclusions

Insulin-dependent T2DM bariatric surgery patients who display a rapid glycemic response to the preoperative LCD are more likely to experience early remission of T2DM postoperatively and greater weight loss.     

Dietary phytoestrogens inhibit experimental aneurysm formation in male mice

Background

The purpose of these experiments was to test the hypothesis that dietary phytoestrogens would diminish experimental aortic aneurysm formation.

Materials and methods

Six-wk-old C57BL/6 mice were divided into groups, fed either a diet with minimal phytoestrogen content or a regular commercial rodent diet with high phytoestrogen content for 2 wk. At the age of 8 wk, aortic aneurysms were induced by infusing the isolated infrarenal abdominal aorta with 0.4% elastase for 5 min. Mice were recovered and the diameter of the infused aorta was measured at postoperative days 3, 7, and 14. Abdominal aorta samples were collected for histology, cytokine array, and gelatin zymography after aortic diameter measurement. Blood samples were also collected to determine serum phytoestrogens and estradiol levels. Multiple-group comparisons were done using an analysis of variance with post hoc Tukey tests.

Results

Compared with mice on a minimal phytoestrogen diet, mice on a regular rodent diet had higher levels of serum phytoestrogens (male, 1138 ± 846 ng/dL; female, 310 ± 295 ng/dL). These serum phytoestrogen levels were also much higher than their own endogenous estradiol levels (109-fold higher for males and 35.5-fold higher for females). Although aortic diameters of female mice were unaffected by the phytoestrogen concentration in the diets, male mice on the regular rodent diet (M+ group) developed smaller aortic aneurysms than male mice on the minimal phytoestrogen diet (M− group) on postoperative day 14 (M+ 54.8 ± 8.8% versus M− 109.3 ± 37.6%; P < 0.001). During aneurysm development (postoperative days 3 and 7), there were fewer neutrophils, macrophages, and lymphocytes in the aorta from the M+ group than from the M− group. Concentrations of multiple proinflammatory cytokines (matrix metalloproteinases [MMPs]; interleukin 1β [IL-1β]; IL-6; IL-17; IL-23; monocyte chemoattractant protein-1; regulated on activation, normal T cell expressed and secreted; interferon γ; and tumor necrosis factor α) from aortas of the M+ group were also lower than those from the aortas of the M− group. Zymography also demonstrated that the M+ group had lower levels of aortic MMP-9s than the M− group on postoperative day 14 (P < 0.001 for pro-MMP-9, P < 0.001 for active MMP-9).

Conclusions

These results suggest that dietary phytoestrogens inhibit experimental aortic aneurysm formation in male mice via a reduction of the inflammatory response in the aorta wall. The protective effect of dietary phytoestrogens on aneurysm formation warrants further investigation.     

Do laparoscopic skills transfer to robotic surgery?

Background

Identifying the set of skills that can transfer from laparoscopic to robotic surgery is an important consideration in designing optimal training curricula. We tested the degree to which laparoscopic skills transfer to a robotic platform.

Methods

Fourteen medical students and 14 surgery residents with no previous robotic but varying degrees of laparoscopic experience were studied. Three fundamentals of laparoscopic surgery tasks were used on the laparoscopic box trainer and then the da Vinci robot: peg transfer (PT), circle cutting (CC), and intracorporeal suturing (IS). A questionnaire was administered for assessing subjects' comfort level with each task.

Results

Standard fundamentals of laparoscopic surgery scoring metric were used and higher scores indicate a superior performance. For the group, PT and CC scores were similar between robotic and laparoscopic modalities (90 versus 90 and 52 versus 47; P > 0.05). However, for the advanced IS task, robotic-IS scores were significantly higher than laparoscopic-IS (80 versus 53; P < 0.001). Subgroup analysis of senior residents revealed a lower robotic-PT score when compared with laparoscopic-PT (92 versus 105; P < 0.05). Scores for CC and IS were similar in this subgroup (64 ± 9 versus 69 ± 15 and 95 ± 3 versus 92 ± 10; P > 0.05). The robot was favored over laparoscopy for all drills (PT, 66.7%; CC, 88.9%; IS, 94.4%).

Conclusions

For simple tasks, participants with preexisting skills perform worse with the robot. However, with increasing task difficulty, robotic performance is equal or better than laparoscopy. Laparoscopic skills appear to readily transfer to a robotic platform, and difficult tasks such as IS are actually enhanced, even in subjects naive to the technology.     

A novel animal model of gastrointestinal obstruction for the development of stent

Background

The need for newer gastrointestinal (GI) stents has been continuously raised. Newly developed stents are generally tested for physical properties in vitro and directly introduced to clinical practice because there is no reliable animal model of GI obstruction. The aim of this study was to establish an animal model both that can represent obstruction of the GI tract and be used to develop new stents.

Material and methods

Surgical obstruction of the descending colon by wrapping with a nonabsorbable synthetic mesh and rubber bands was made in 17 healthy mongrel dogs. Four days later, a covered self-expanding metallic stent was placed for the obstructed segment in each dog under fluoroscopic guidance. Patency and migration of the inserted stents were evaluated clinically on a daily basis and fluoroscopically on a weekly basis. After sacrifice of the dogs, the degree and extent of residual colonic obstruction were assessed fluoroscopically. The specimen of the colonic obstructed segment was examined microscopically.

Results

In all 17 mongrel dogs, segmental obstruction in the descending colon was successfully created and confirmed with fluoroscopic examination using a contrast medium. The percentage of luminal narrowing ranged from 99%–100%. Stent placement was technically successful in all 17 dogs. During the follow-up period, stent migration occurred in 12 dogs and indwelling time of a stent ranged from 0–95 d (mean 29.2 ± 38.8 d). On postmortem pathologic examination, it was found that fibrosis had newly formed outside the colonic longitudinal muscle layer in all dogs.

Conclusions

Our canine colonic obstruction model is the first animal model that can be feasible for developing a new design of stent and provide in vivo data on complications, particularly stent migration.     

Blunt traumatic aortic injuries of the ascending aorta and aortic arch: A clinical multicentre study

Objective

To report the clinical and radiological characteristics, management and outcomes of traumatic ascending aorta and aortic arch injuries.

Methods

Historic cohort multicentre study including 17 major trauma patients with traumatic aortic injury from January 2000 to January 2011.

Results

The most common mechanism of blunt trauma was motor-vehicle crash (47%) followed by motorcycle crash (41%). Patients sustaining traumatic ascending aorta or aortic arch injuries presented a high proportion of myocardial contusion (41%); moderate or greater aortic valve regurgitation (12%); haemopericardium (35%); severe head injuries (65%) and spinal cord injury (23%). The 58.8% of the patients presented a high degree aortic injury (types III and IV). Expected in-hospital mortality was over 50% as defined by mean TRISS 59.7 (SD 38.6) and mean ISS 48.2 (SD 21.6) on admission. Observed in-hospital mortality was 53%. The cause of death was directly related to the ATAI in 45% of cases, head and abdominal injuries being the cause of death in the remaining 55% cases. Long-term survival was 46% at 1 year, 39% at 5 years, and 19% at 10 years.

Conclusions

Traumatic aortic injuries of the ascending aorta/arch should be considered in any major thoracic trauma patient presenting cardiac tamponade, aortic valve regurgitation and/or myocardial contusion. These aortic injuries are also associated with a high incidence of neurological injuries, which can be just as lethal as the aortic injury, so treatment priorities should be modulated on an individual basis.     

The effect of fluoxetine on ischemia–reperfusion after aortic surgery in a rat model

Background

Aortic ischemia–reperfusion (IR) is an important factor in the development of postoperative acute lung injury after abdominal aortic surgery. The aim of the present study was to examine the effect of fluoxetine (Flx), a selective serotonin reuptake inhibitor widely used as a preoperative anxiolytic, on lung injury induced by abdominal aortic IR in rats.

Methods

Wistar rats were randomized into three groups (n = 7 per group): (1) control (sham laparotomy); (2) IR without Flx (60-min ischemia and 120-min reperfusion); (3) IR with Flx (Flx + IR) (Flx 20 mg/kg/d, intraperitoneally for 3 d before surgery). Lung tissue samples and bronchoalveolar lavage (BAL) were obtained for biochemical analysis of oxidative status. Ischemia-modified albumin (IMA) level and protein concentrations in BAL and lung wet to dry weight ratios were determined. Histologic evaluation of the lung tissues was also performed.

Results

IR without Flx led to significant increase in lipid hydroperoxide, malondialdehyde, and pro-oxidant–antioxidant balance and decrease in superoxide dismutase, glutathione, and ferric reducing antioxidant power activities (P < 0.05 versus control), whereas Flx was able to restore these parameters (P > 0.05 versus control) and decrease IMA level (P < 0.01 versus control) and protein concentration (P < 0.05 versus control) in BAL and wet to dry lung weight ratio. Histologic evaluation showed that Flx attenuated the morphologic changes associated with lung injury.

Conclusions

The results indicate that Flx confers protection against aortic IR-induced lung oxidative stress and cellular integrity. IMA levels in BAL may be used as a follow-up marker for the efficacy of treatment in lung injury.     

Comparison of surgical outcomes between papillary thyroid cancer patients treated with the Harmonic ACE scalpel and LigaSure Precise instrument during conventional thyroidectomy: a single-blind prospective randomized controlled trial

Background

The aim of this study was to evaluate the safety and efficacy of thyroidectomy using the Harmonic ACE scalpel (HS) or the LigaSure Precise (LS) instrument in conventional thyroidectomy.

Materials and methods

A prospective, randomized controlled trial was performed. Between August 2011 and June 2012, 832 patients who required thyroidectomy for papillary thyroid cancer were randomized into groups treated with either the HS or the LS instrument. Operative time and surgical morbidities were analyzed.

Results

A total of 320 patients (HS group, N = 164; LS instrument group, N = 156) were randomized for analysis according to the intention-to-treat principle. There were no statistically significant differences in the operative times (HS group versus LS instrument group: 71.93 ± 18.26 versus 75.15 ± 20.13; P = 0.423), postoperative transient hypoparathyroidism (13.4% versus 14.1%; P = 0.858), and permanent recurrent laryngeal nerve injuries between the two groups.

Conclusions

In this study, both hemostatic devices were safe and effective in terms of postoperative results and complications without any differences.     

T-cell activation Rho GTPase–activating protein expression varies with inflammation location and severity in Crohn's disease

Background

The T-cell activation Rho GTPase–activating protein (TAGAP) gene has a regulatory role in T cell activation. We have previously suggested a correlation between the TAGAP-associated single nucleotide polymorphism rs212388 and protection from anal sepsis in Crohn's disease (CD) patients. The present study sought to evaluate TAGAP's expression in colonic tissue of CD patients with varying disease severity and location.

Materials and methods

Five transverse, 17 left, and five sigmoid colectomy specimens from 27 CD patients with varying disease severity (16 male, mean age at diagnosis 26.4 ± 2.2 y) were evaluated for TAGAP messenger RNA expression. Fisher exact, Mann–Whitney, and Welch two-sample t-tests were used for statistical evaluation. Immunohistochemistry confirmed results.

Results

Patients with tissue demonstrating lower TAGAP messenger RNA expression (less than the overall mean) were younger at diagnosis (mean age 21.1 ± 6.3 versus 32.5 ± 13 y, P = 0.009). Increased TAGAP expression was seen in moderate or severely diseased tissue versus tissue with no or mild disease (RQ = 1.3 ± 0.34 versus 0.53 ± 0.09, P = 0.050). This was the most dramatic in the sigmoid colon (P = 0.041). TAGAP expression was increased in more distal tissue with a significant difference seen when comparing transverse versus sigmoid colon with moderate or severe disease (0.51 ± 0.14 versus 1.9 ± 0.37, P = 0.049).

Conclusions

Colonic expression of TAGAP in CD patients varied according to disease severity and location, being the most elevated in patients with severe disease in the sigmoid colon. Whether changes in TAGAP expression are a result of disease response or inherent to the disease pathophysiology itself remains to be determined. This gene warrants further investigation for its role in CD.     

Unilateral thyroidectomy for the treatment of benign multinodular goiter

Background

Benign multinodular goiter (MNG) is one of the most commonly treated thyroid disorders. Although bilateral resection is the accepted surgical treatment for bilateral MNG, the appropriate surgical resection for unilateral MNG continues to be debated. Bilateral resection generally has lower recurrence rates but higher complication rates than unilateral resection. Therefore, the purpose of this study was to define the recurrence and complication rates of unilateral and bilateral resections to determine the appropriate intervention for patients with unilateral, benign MNG.

Methods

We reviewed a prospectively maintained database of all patients who underwent a thyroidectomy for treatment of benign MNG at a single institution between May 1994 and December 2011. All patients with bilateral MNG were treated with bilateral resection. Surgical treatment for unilateral MNG was determined by surgeon preference, with all but one surgeon opting for unilateral resection to treat unilateral MNG. Data were reported as means ± standard error of the mean. Chi-squared analysis was used to determine statistical significance at a level of P < 0.05.

Results

A total of 683 patients underwent thyroidectomy for MNG. Of these patients, 420 (61%) underwent unilateral resection and 263 patients (39%) underwent total thyroidectomy. The mean age was 52 ± 17 y, and 542 patients (79%) were female. The mean follow-up time was 46.1 ± 1.9 mo. The rate of recurrent disease was similar between unilateral (2%, n = 10) and bilateral (1%, n = 3) resections (P = 0.248). Unilateral resection patients had a lower total complication rate than patients with bilateral resections (8% versus 26%, P < 0.001); however, there was no difference in the rate of permanent complications (0.2% versus 1%, P = 0.133). Thyroid hormone replacement was rare in unilateral resection patients but necessary in all patients with bilateral resection (19% versus 100%, P < 0.001).

Conclusions

Patients that had unilateral resections endured less overall morbidities than those who had bilateral resections, and their risk of recurrent disease was similar. They were also significantly less likely to require lifelong hormone replacement therapy postoperatively. Although bilateral resection remains the recommended treatment for bilateral MNG, these data strongly support the use of unilateral thyroidectomy for the treatment of unilateral, benign MNG.     

The effects of propofol and dexmedetomidine infusion on fluid responsiveness in critically ill patients

Background

We studied the effects of propofol or dexmedetomidine on preload dependency and fluid responsiveness in critically ill patients.

Methods

In the study, we included 91 patients with acute circulatory failure (70 ± 15 y) who received propofol (n = 45 patients, PROP group) or dexmedetomidine (n = 46 patients, DEX group). An initial passive leg-raising (PLR 1) test was performed in all patients to evaluate preload dependency at baseline. Propofol and dexmedetomidine were infused and titrated according to the Richmond Agitation Sedation Scale; the results ranged from −2 to −1, and the bispectral index values ranged from 60–75. A second PLR test (PLR 2) was performed before administration of a 250-mL normal saline fluid challenge over a 5-min period. We obtained central venous pressure and cardiac index (CI) measurements before and after the two PLR tests and volume expansion. An increase of ≥10% in CI during PLR was considered to be a positive test finding that was indicative of preload dependency, whereas an increase of <10% in CI during PLR was considered to be a negative test finding.

Results

At baseline, 22 of 45 patients had negative PLR 1 in the PROP group, whereas 20 of 46 patients had negative PLR 1 in the DEX group. After propofol or dexmedetomidine sedation, there were significant decreases in CI (−9.5% [±6.6%] versus −16.4% [±8.5%], P < 0.001) in the PROP and DEX groups, respectively. In the PROP group, there were significant increases in CI (+18.4% [±9.5%] versus +10.7% [±12.3%], P < 0.05) induced by PLR 2 compared with that induced by PLR 1. In the DEX group, there were no significant increases in CI (+13.2% [±14.9%] versus +12.8% [±17.7%]) induced by PLR 2 compared with that induced by PLR 1. Although the mean arterial pressure values increased comparably with the volume expansion observed in both groups, the volume expansion resulted in a significantly higher increase in CI compared with the baseline values in the PROP group (3.2 ± 0.8 versus 3.2 ± 0.7 L/min/m²) but not in the DEX group (2.9 ± 0.7 versus 3.1 ± 0.8 L/min/m², P < 0.05).

Conclusions

We observed that propofol infusion, but not dexmedetomidine infusion, can increase preload dependency and fluid responsiveness in patients with circulatory failure.     

The inflammatory sequelae of aortic balloon occlusion in hemorrhagic shock

Background

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a hemorrhage control and resuscitative adjunct that has been demonstrated to improve central perfusion during hemorrhagic shock. The aim of this study was to characterize the systemic inflammatory response associated and cardiopulmonary sequelae with 30, 60, and 90 min of balloon occlusion and shock on the release of interleukin 6 (IL-6) and tumor necrosis factor alpha.

Materials and methods

Anesthetized female Yorkshire swine (Sus scrofa, weight 70–90 kg) underwent a 35% blood volume–controlled hemorrhage followed by thoracic aortic balloon occlusion of 30 (30-REBOA, n = 6), 60 (60-REBOA, n = 8), and 90 min (90-REBOA, n = 6). This was followed by resuscitation with whole blood and crystalloid over 6 h. Animals then underwent 48 h of critical care with sedation, fluid, and vasopressor support.

Results

All animals were successfully induced into hemorrhagic shock without mortality. All groups responded to aortic occlusion with a rise in blood pressure above baseline values. IL-6, as measured (picogram per milliliter) at 8 h, was significantly elevated from baseline values in the 60-REBOA and 90-REBOA groups: 289 ± 258 versus 10 ± 5; P = 0.018 and 630 ± 348; P = 0.007, respectively. There was a trend toward greater vasopressor use (P = 0.183) and increased incidence of acute respiratory distress syndrome (P = 0.052) across the groups.

Conclusions

REBOA is a useful adjunct in supporting central perfusion during hemorrhagic shock; however, increasing occlusion time and shock results in a greater IL-6 release. Clinicians must anticipate inflammation-mediated organ failure in post-REBOA use patients.     

Flutamide fails to reduce resuscitation requirements in a porcine ischemia-reperfusion model

Background

Hemorrhagic shock and subsequent resuscitation can lead to ischemia-reperfusion injury, followed by multiorgan failure and death. Flutamide, a vasoactive nonsteroidal antiandrogen compound, is thought to improve tissue and organ perfusion. We tested whether administration of flutamide-cyclodextrin (FLU-CYD) alters physiologic parameters or resuscitation requirements in a porcine model of severe acidosis and shock secondary to combined hemorrhage + ischemia-reperfusion injury.

Methods and materials

Fifteen male pigs underwent a 35% blood-volume hemorrhage. Ischemia was induced by cross-clamping the supraceliac aorta for 50 min followed by reperfusion and resuscitation. FLU-CYD complex was administered during aortic clamping. Fluid resuscitation and epinephrine were titrated by protocol to maintain mean arterial pressure ≥40 mm Hg for 6 h. Sequential laboratory results were obtained and serum levels of FLU and 2-hydroxy-flutamide (FLUOH) were measured by mass spectrometry.

Results

Mean requirements for injured control swine were 14.6 (± 1.21 standard error of the mean [SEM]) L crystalloid saline and 0.59 (± 0.29 SEM) g epinephrine, compared with 16.30 (± 1.33 SEM) L and 0.54 (± 0.16 SEM) g, respectively, in the FLU-CYD group (both P > 0.05). There were no significant differences in central hemodynamics between control and experimental groups. No significant differences for pH, bicarbonate, fibrinogen, or international normalized ratio were evident. FLU-CYD resuscitation was associated with a significant increase in lactate levels compared with controls (10.1 versus 5.7 mmol/L, P < 0.05). Histologic injury was significantly increased in the livers of FLU-CYD compared with sham (P = 0.022). High serum levels of FLU and the active metabolite FLUOH were measurable throughout the resuscitation period.

Conclusions

Flutamide failed to show any benefit to resuscitation in a model of severe injury and was associated with increased acidosis, hemodilution, and liver injury compared with standard crystalloid resuscitation.     

Clinical outcomes following bowel resection versus reduction of intussusception

Background

Intussusception is most commonly managed with air-contrast reduction. However, when this fails, emergent operation with resection or manual reduction is indicated. It is not known if there are advantages to resection compared with manual reduction.

Methods

A retrospective review of all patients receiving operative care for intussusception from February 2000 to December 2011. Patients undergoing intestinal resection were compared with those treated with manual reduction alone.

Results

Of 111 patients, 49 underwent resection and 62 underwent manual reduction. Mean (±SD) time to oral intake favored manual reduction (2.1 ± 1.2 versus 2.6 ± 1.2 d, respectively, P = 0.05). Manual reduction was associated with a greater need for repeat imaging (47% versus 18%, P = 0.002) and the only recurrences were with manual reduction (8% versus 0%, P = 0.1). Mean duration of stay was no different (P = 0.36), nor was the need for reoperation (P = 0.9).

Conclusions

Patients undergoing manual reduction have an increased number of radiographic imaging procedures. The surgeon should have a low threshold for resection for intussusceptions requiring operative management.     

Reduction aortoplasty and external wrapping for moderately sized tubular ascending aortic aneurysm with concomitant operations

Background

Replacement of the ascending aorta with a prosthetic graft is the preferred surgical procedure for an ascending aortic aneurysm. The choice of external wrapping of the aorta is a simple, fast, and effective method for moderately sized ascending aortic aneurysms with concomitant operations. In this study, we present the midterm results of 62 patients undergoing reduction aortoplasty with external wrapping and different cardiac procedures.

Methods

The study group consisted of 48 male and 14 female patients with a mean age of 59.3 ± 6.0 years. Measurement of the ascending aorta diameters was obtained at three points: before surgery, during the early postoperative period, and during the follow-up. The mean preoperative aortic diameter was 52.7 ± 0.5 mm. In all patients, the ascending aortic aneurysm was repaired by reduction aortoplasty with external wrapping.

Results

Mean follow-up time was 39.6 ± 18.0 months. There was only one mortality (1.6%) as a result of septic multiple-organ failure and no major surgical complications in the 30-day postoperative period. Reduction aortoplasty of the ascending aorta with external wrapping resulted in a significant reduction of the ascending aorta in all patients (p = 0.000). There was an increase in the mean aortic diameter during the follow-up period (p = 0.000). Although this increase was statistically significant, all measurements of the follow-up period were still within normal range.

Conclusions

External wrapping of the aorta offers excellent results with very low mortality and morbidity, and it can be regarded as a safe and effective method for the treatment of ascending aortic aneurysm in selected patients. However, the patients should be carefully monitored for redilatation after the procedure.     

Radiation exposure from head computed tomography scans in pediatric trauma

Background

We have previously reported that children receive significantly less radiation exposure after abdominal and/or pelvis computed tomography (CT) scanning for acute appendicitis when performed at our children's hospital (CH) rather than at outside hospitals (OH). In this study, we compare the amount of radiation children receive from head CTs for trauma done at OH versus those at our CH.

Methods

A retrospective chart review was performed on all children transferred to our hospital after receiving a head CT for trauma at an OH between July 2012 and December 2012. These children were then blindly case matched based on date, age, and gender to children at our CH.

Results

There were 50 children who underwent head CT scans for trauma at 28 OH. There were 21 females and 29 males in each group. Average age was 7.01 ± 0.5 y at the OH and 7.14 ± 6.07 at our CH (P = 0.92). Average weight was 30.81 ± 4.69 kg at the OH and 32.69 ± 27.21 kg at our CH (P = 0.81). Radiation measures included dose length product (671.21 ± 22.6 mGycm at OH versus 786.28 ± 246.3 mGycm at CH, P = 0.11) and CT dose index (53.4 ± 2.26 mGy at OH versus 49.2 ± 12.94 mGy at CH, P = 0.56).

Conclusions

There is no significant difference between radiation exposure secondary to head CTs for traumatic injuries performed at OH and those at a dedicated CH.     

Laparoscopic pyloromyotomy: comparing the arthrotomy knife to the Bovie blade

Background

Laparoscopic pyloromyotomy was performed at our institution using an arthrotomy knife until it became unavailable in 2010. Thus, we adapted the use of the blunt Bovie tip, which can be used with or without electrocautery to perform the myotomy. This study compared the outcomes between using the arthrotomy knife versus the Bovie blade in laparoscopic pyloromyotomies.

Materials and methods

Retrospective review was performed on all laparoscopic pyloromyotomy patients from October 2007 to September 2012. Arthrotomy knife pyloromyotomy patients were compared with those performed with the Bovie blade. Patient demographics, diagnostic measurements, electrolyte levels, length of stay, operative time, and complications were compared.

Results

A total of 381 patients were included, with 191 in the arthrotomy group and 190 in the Bovie blade group. No significant differences existed between groups in age, weight, gender, pyloric dimensions, electrolyte levels, or length of stay. Mean operative times were 15.8 ± 5.6 min with knife and 16.4 ± 5.3 min for Bovie blade (P = 0.24). In the arthrotomy knife group, there was one incomplete pyloromyotomy and one omental herniation. There was one wound infection in each group. Readmission rate was greater in the arthrotomy knife group (5.7%) versus the Bovie blade group (3.1%).

Conclusions

The Bovie blade appears to offer no objective disadvantages compared with the arthrotomy knife when performing laparoscopic pyloromyotomy.     

Large-for-size liver transplantation: a flowmetry study in pigs

Background

Ischemia–reperfusion injury is partly responsible for morbidity in pediatric liver transplantation. Large-for-size (LFS) liver transplantation has not been fully studied in the pediatric population, and the effects of reperfusion injury may be underestimated.

Materials and methods

Thirteen Landrace–Large white pigs weighing 23 kg (range, 17–38 kg) underwent orthotopic liver transplantation. They were divided into two groups according to the size of the donor body: LFS and control (CTRL). After transplantation, the abdominal cavity of the recipient was kept open and portal venous flow (PVF) was measured after 1 h. The ratio of recipient PVF (PVFr) to donor PVF was used to establish correlations with ischemia and reperfusion parameters. Liver biopsies were taken 1 h after transplantation to assess ischemia and reperfusion and to quantify the gene expression of endothelial nitric oxide synthase, interleukin 6, BAX, and BCL.

Results

Recipient weight, total ischemia time, and warm ischemia time were similar between groups. Among hemodynamic and metabolic analyses, pH, central arteriovenous PCO₂ difference, and AST were statistically worse in the LFS group than in the CTRL group. The same was found with endothelial nitric oxide synthase (0.41 ± 0.18 versus 1.56 ± 0.78; P = 0.02) and interleukin 6 (4.66 ± 4.61 versus 16.21 ± 8.25; P = 0.02). In the LFS group, a significant decay in the PVFr was observed in comparison with the CTRL group (0.93 ± 0.08 and 0.52 ± 0.11, respectively; P < 0.001).

Conclusions

The implantation of a graft was responsible for poor hemodynamic status of the recipient 1 h after transplantation. Furthermore, the LFS group demonstrated markers of ischemia and reperfusion that were worse when compared with the CTRL group and exhibited a more significant decrease in PVF from donor to recipient.