Tight contact technique during side-to-side laser tissue soldering of rabbit aortas improves tensile strength

BACKGROUND: Cerebral revascularization may be indicated either for blood flow preservation or flow augmentation, often in clinical situations where neither endovascular nor standard surgical intervention can be performed. Cerebral revascularization can be performed by using a temporary occlusive or a non-occlusive technique. Both of these possibilities have their specific range of feasibility. Therefore non-occlusive revascularization techniques have been developed. To further reduce the risks for patients, less time consuming, sutureless techniques such as laser tissue soldering are currently being investigated. METHOD: In the present study, a new technique for side-to-side anastomosis was developed. Using a "sandwich technique", two vessels are kept in close contact during the laser soldering. Thoraco-abdominal aortas from 24 different rabbits were analyzed for laser irradiation induced tensile strength. Two different irradiation modes (continuous and pulsed) were used. The results were compared to conventional, noncontact laser soldering. Histology was performed using HE, Mason's Trichrome staining. FINDINGS: The achieved tensile strengths were significantly higher using the close contact "sandwich technique" as compared to the conventional adaptation technique. Furthermore, tensile strength was higher in the continuously irradiated specimen as compared to the specimen undergoing pulsed laser irradiation. The histology showed similar denaturation areas in both groups. The addition of a collagen membrane between vessel components reduced the tensile strength. CONCLUSION: These first results proved the importance of close and tight contact during the laser soldering procedure thus enabling the development of a "sandwich laser irradiation device" for in vivo application in the rabbit.

Sirolimus and intraoperative hyperthermic peritoneal chemoperfusion with mitomycin-C do not impair healing of bowel anastomoses

Surgeons will increasingly have to address the development of gastrointestinal disease in transplant patients or deal with extended bowel resection and bowel anastomosis in advanced cancer patients. Immunosuppressants as well as intraoperative hyperthermic peritoneal chemoperfusion (IHPC) may alter intestinal anastomotic healing. We evaluated the effects of the immunosuppressant sirolimus and of IHPC on healing and stability of bowel anastomoses in pigs. Twenty-four pigs were divided into four groups (SIR: sirolimus was administered orally; IHPC: animals received IHPC with mitomycin-C; COMP: combination of sirolimus and IHPC was administered; CON: sham-treated control group). Animals underwent hand-sutured small bowel and left colon anastomoses and were killed on postoperative day 4. Anastomoses were evaluated by morphometric analysis and immunohistochemistry (IHC) and by measuring the bursting pressure (BP). In all experimental groups (SIR, IHPC, COMP), anastomotic BPs remained unaltered and were not statistically different compared with control (CON). In addition, ileum villous height and colonic crypt depth analysis revealed no significant difference in mucosal thickness, and IHC showed no difference among groups in proliferation, as assessed by the number of KI-67- and bromodeoxyuridine-labeled cells. Immunosuppression with sirolimus as well as IHPC with mitomycin-C do not alter healing of intestinal anastomosis in pigs.

Goal-directed colloid administration improves the microcirculation of healthy and perianastomotic colon

BACKGROUND: The aim of this study was to compare the effects of goal-directed colloid fluid therapy with goal-directed crystalloid and restricted crystalloid fluid therapy on healthy and perianastomotic colon tissue in a pig model of colon anastomosis surgery. METHODS: Pigs (n = 27, 9 per group) were anesthetized and mechanically ventilated. A hand-sewn colon anastomosis was performed. The animals were subsequently randomized to one of the following treatments: R-RL group, 3 ml x kg(-1) x h(-1) Ringer lactate (RL); GD-RL group, 3 ml x kg(-1) x h(-1) RL + bolus 250 ml of RL; GD-C group, 3 ml x kg(-1) x h(-1) RL + bolus 250 ml of hydroxyethyl starch (HES 6%, 130/0.4). A fluid bolus was administered when mixed venous oxygen saturation dropped below 60%. Intestinal tissue oxygen tension and microcirculatory blood flow were measured continuously. RESULTS: After 4 h of treatment, tissue oxygen tension in healthy colon increased to 150 +/- 31% in group GD-C versus 123 +/- 40% in group GD-RL versus 94 +/- 23% in group R-RL (percent of postoperative baseline values, mean +/- SD; P < 0.01). Similarly perianastomotic tissue oxygen tension increased to 245 +/- 93% in the GD-C group versus 147 +/- 58% in the GD-RL group and 116 +/- 22% in the R-RL group (P < 0.01). Microcirculatory flow was higher in group GD-C in healthy colon. CONCLUSIONS: Goal-directed colloid fluid therapy significantly increased microcirculatory blood flow and tissue oxygen tension in healthy and injured colon compared to goal-directed or restricted crystalloid fluid therapy.

"Rapid two-stage" Norwood operation in a child with multiorgan failure

The Norwood I operation continues to be a procedure with significant operative mortality. One well-accepted risk factor for death after the first step of the Norwood operation is critical preoperative status. We describe herein a new concept for the treatment of patients with hypoplastic left heart syndrome (HLHS) in very poor preoperative condition. This is a case report of a child who was born in a rural hospital. On the second day of life he was referred to our center in multiorgan failure. There were signs of liver dysfunction and the child was anuric. Therapy was started immediately with prostaglandin and vasodilators as well as diuretics, milrinone, and dobutamine. However, systemic perfusion continued to be insufficient. Finally, the child was placed on a ventilator. On the fourth day of life, bilateral pulmonary artery (PA) banding was performed and circulation stabilized immediately. Two hours after the operation urine output started. Liver function stabilized over the next couple of days. Two days after PA banding the child was weaned from the ventilator. On the 12th day of life a Norwood operation with PA debanding and a right ventricle-PA conduit was performed, and 2 days postoperatively the child was weaned from the ventilator. Twenty days after the operation he was discharged home. When the boy was 4 months old a bidirectional cavopulmonary anastomosis was performed. In selected cases of patients with HLHS with very poor hemodynamic conditions, a rapid two-stage approach with bilateral banding followed by a Norwood operation after cardiac stabilization can be recommended.

Review of 197 consecutive free flap reconstructions in the lower extremity

Complications and failures after microvascular free tissue transfer for lower extremity reconstruction have a negative impact on postoperative course and final outcome. Therefore, a 10-year analysis on lower extremity reconstruction with free flaps was performed with a special emphasis on patient co-morbidities such as cardiovascular diseases, diabetes mellitus, body mass index and history of smoking, in order to identify potential risk factors. Complications such as haematoma, seroma, infection, wound dehiscence, as well as partial flap loss, postoperative thrombosis of the anastomosis and eventual total flap loss were gathered from the medical records. Limb salvage was 100%, however 40% suffered from complications ranging from minor wound dehiscence to total flap loss. None of the above-mentioned potential risk factors was associated with an increased rate of complications. However, in flaps that required revision for thrombosis, the age of the patients was significantly higher in the group of flaps that eventually failed when compared to flaps that were salvaged. In conclusion, lower extremity reconstruction with microvascular free tissue transfer is a safe and reliable procedure with a high success rate, however partial flap loss remains an important issue. Increased age was the only factor identified with an increased risk for subsequent flap loss in cases that were revised for thrombosis.

Temporary neurological dysfunction after surgery of the thoracic aorta: a predictor of poor outcome and impaired quality of life

BACKGROUND: Transient neurological dysfunction (TND) consists of postoperative confusion, delirium and agitation. It is underestimated after surgery on the thoracic aorta and its influence on long-term quality of life (QoL) has not yet been studied. This study aimed to assess the influence of TND on short- and long-term outcome following surgery of the ascending aorta and proximal arch. METHODS: Nine hundred and seven patients undergoing surgery of the ascending aorta and the proximal aortic arch at our institution were included. Two hundred and ninety patients (31.9%) underwent surgery because of acute aortic dissection type A (AADA) and 617 patients because of aortic aneurysm. In 547 patients (60.3%) the distal anastomosis was performed using deep hypothermic circulatory arrest (DHCA). TND was defined as a Glasgow coma scale (GCS) value <13. All surviving patients had a clinical follow up and QoL was assessed with an SF-36 questionnaire. RESULTS: Overall in-hospital mortality was 8.3%. TND occurred in 89 patients (9.8%). As compared to patients without TND, those who suffered from TND were older (66.4 vs 59.9 years, p<0.01) underwent more frequently emergent procedures (53% vs 32%, p<0.05) and surgery under DHCA (84.3% vs 57.7%, p<0.05). However, duration of DHCA and extent of surgery did not influence the incidence of TND. In-hospital mortality in the group of patients with TND compared to the group without TND was similar (12.0% vs 11.4%; p=ns). Patients with TND suffered more frequently from coronary artery disease (28% vs 20.8%, p=ns) and were more frequently admitted in a compromised haemodynamic condition (23.6% vs 9.9%, p<0.05). Postoperative course revealed more pulmonary complications such as prolonged mechanical ventilation. Additional to their transient neurological dysfunction, significantly more patients had strokes with permanent neurological loss of function (14.6% vs 4.8%, p<0.05) compared to the patients without TND. ICU and hospital stay were significantly prolonged in TND patients (18+/-13 days vs 12+/-7 days, p<0.05). Over a mean follow-up interval of 27+/-14 months, patients with TND showed a significantly impaired QoL. CONCLUSION: The neurological outcome following surgery of the ascending aorta and proximal aortic arch is of paramount importance. The impact of TND on short- and long-term outcome is underestimated and negatively affects the short- and long-term outcome.

Is a sustaining rod necessary for diverting loop ileostomy?

Objective: Whether or not a protective stoma reduces the rate of anastomotic leakage after distal colorectal anastomosis is still discussed controversially. It does however facilitate clinical management once leakage has occurred. Loop ileostomies seem to be associated with a lower morbidity and a better quality of life compared to loop colostomies. Generally, diverting loop ileostomies are secured at skin level by means of a supporting device in order to prevent retraction of the ileostomy into the abdomen. However, due to the supporting rod, difficulties may occur in applying a stoma bag correctly and leakage of faeces onto the skin may occur even with correct eversion of the afferent limb. Our aim was to compare morbidity and time to self-sufficient stoma-care in patients having a loop ileostomy with rod to those without rod. Methods: A total of 60 patients necessitating loop ileostomy were analyzed. Patients received surgery in of the two involved institutions according to inhouse standard procedures. 30 patients had an ileostomy with rod (VCHK Inselspital) and a further 30 without rod (KSW Winterthur). Morbidity and time to self-sufficiency regarding stoma care was analyzed during the first 90 postoperative days. Morbidity was determined according to a scoring system ranging from 0 to 4 points for any given set of possible complications (bleeding, necrosis, skin irritation, abscess, stenosis, retraction, fistula, prolapse, parastomal hernia, incomplete diversion), where 0 = no complication and 4 = severe complication. Continuous variables were expressed as median (95% Confidence Interval). For comparisons between the groups the Mann-Whitney U test was used, between categorical variables the X2 test was applied. Results: There were no significant differences in length of hospital stay or time to self-sufficient stoma-care between the groups. Although not significant, patients with a rod ileostomy had a tendency towards more stoma-related complications as well as stoma-related reoperations. The number of patients reaching total self-sufficiency regarding stoma care was higher after rodless ileostomy. Conclusion: According to our data, rodless ileostomies seemto fare just as well as those with a supporting rod, with equal morbidity rates and more patients reaching self-sufficient stoma care. Therefore routine application of a rod for diverting loop ileostomy seems unnecessary

Insulin-like growth factor I improves aspects of mycophenolate mofetil-impaired anastomotic healing in an experimental model

BACKGROUND: Patients taking immunosuppressants after transplantation may require intestinal surgery. Mycophenolate mofetil (MMF) has been found to impair the healing of colonic anastomoses in rats. This study examined whether insulin-like growth factor (IGF) I prevents MMF impairment of anastomotic healing. METHODS: Sixty-three rats were divided into three groups (MMF, MMF/IGF and control). Animals underwent a sigmoid colon anastomosis with a 6/0 suture, and were killed on days 2, 4 and 6 after surgery. Investigations included bursting pressure measurement, morphometric analysis, and assessment of mucosal proliferation by 5-bromo-2'-deoxyuridine and Ki67 immunohistochemistry of the anastomoses. RESULTS: The leak rate was three of 21, one of 20 and two of 20 in the MMF, MMF/IGF-I and control groups respectively. Anastomotic bursting pressures were significantly lower in the MMF group than in the control group on days 2 and 4, but there was no significant difference by day 6. Values in the MMF/IGF-I and control groups were similar. Colonic crypt depth was significantly reduced in MMF-treated animals on days 2 and 4, but this impairment was attenuated by IGF-I on day 4. Similarly, IGF-I reduced the negative impact of MMF on mucosal proliferation on days 2 and 6. CONCLUSION: Exogenous IGF-I improves some aspects of MMF-impaired anastomotic healing.

The Cardica C-Port System: clinical and angiographic evaluation of a new device for automated, compliant distal anastomoses in coronary artery bypass grafting surgery--a multicenter prospective clinical trial

OBJECTIVES: The C-Port System (Cardica, Inc, Redwood City, Calif) integrates in one tool all functions necessary to enable rapid automated distal coronary anastomoses. The goal of this prospective, nonrandomized, and multicenter study is to determine the safety and efficacy of this novel anastomotic system. METHODS: Five centers enrolled 133 patients awaiting elective coronary artery bypass grafting surgery. Outcome variables were intraoperative device performance, incidence of device-related adverse events, predischarge and 6-month angiographic graft patency, and 12-month clinical outcome. Independent core laboratories performed qualitative and quantitative angiographic and computed tomographic assessments. RESULTS: The C-Port was used to perform a vein-to-coronary anastomosis in 130 patients. Intraoperative conversion to a hand-sewn anastomosis was necessary in 11 patients because of inadequate target site preparation, inappropriate target vessel selection, or both. Inadequate blood flow related to poor runoff required conversion in 3 additional patients. Three patients died before discharge of causes unrelated to the device. At discharge, 113 patients had a C-Port implant in place, and 104 C-Port anastomoses were studied by means of angiography, resulting in 100 FitzGibbon A, 3 FitzGibbon B, and 1 FitzGibbon 0 classifications. At 6 months, one additional patient died of a device-unrelated cause, and 98 patients were evaluated by means of angiography (n = 89). Overall patency (FitzGibbon A) was 92.1%. Three C-Port anastomoses were rated FitzGibbon B, and 4 were rated FitzGibbon 0. At 12 months, 107 (98.2%) of 109 alive patients were followed up, without any reports of device-related major adverse cardiac events. CONCLUSIONS: The C-Port System allows for a rapid, reliable, and compliant distal anastomosis and yields favorable 6-month angiographic and 12-month clinical results when compared with published studies.

Six-month angiographic follow-up of the PAS-Port II clinical trial

BACKGROUND: The PAS-Port device (Cardica, Redwood City, CA) allows the rapid deployment of a clampless proximal anastomosis between a vein graft and the aorta. METHODS: Fifty-four patients awaiting elective coronary artery bypass graft surgery were enrolled. Outcome variables were intraoperative device performance, early and 6- month angiographic graft patency, and 12-month clinical follow-up. RESULTS: Sixty-three PAS-Port devices were deployed in 54 patients. Two deployments were unsuccessful. There were no reoperations for bleeding. Two patients died of causes unrelated to the device. Patency evaluation at discharge was performed by angiogram on 49 implants and computed tomography in 2 implants (86% follow-up). At discharge, all evaluated grafts were patent (100%) and rated Fitzgibbon A. At 6-month follow-up, there was no additional mortality; 47 implants (88% follow-up) were evaluated by angiography (Fitzgibbon O [n = 1], Fitzgibbon B [n = 1], and Fitzgibbon A [n = 45]) and 5 by computed tomography. All grafts but 1 were patent (98.1%). At 12 months, 2 additional patients died of causes unrelated to the PAS-Port implant. Forty-six of 50 alive patients (95.8%) were followed up without any reports of device-related major adverse cardiac events. CONCLUSIONS: Discharge (100%) and 6-month patency (98%) are excellent; patency and 12 months' clinical follow-up compares favorably with data from historical hand-sewn controls. The PAS-Port system safely allows the clampless creation of a proximal anastomosis.

Impact of intraoperative behavior on surgical site infections

BACKGROUND: The aim of this study was to identify intraoperative risk factors for surgical site infections (SSIs), which are accessible to interventions. We evaluated the effect of extensive intraoperative antiseptic measures and the impact of the behavior of members of the surgical team on SSIs. METHODS: Standard versus extensive antiseptic measures were randomly assigned in 1,032 surgical patients. The adherence to principles of asepsis by members of the surgical team was assessed prospectively. RESULTS: The rate of SSI was 14% with standard antiseptic measures and 15% with extensive measures (P = .581). Multivariate analysis identified following independent risk factors: lapses in discipline (odds ratio [OR] 2.02, confidence interval [CI] 1.05-3.88), intestinal anastomosis (OR 6.74, CI 3.42-13.30), duration of operation more than 3 hours (OR 3.34, CI 1.82-6.14), and body mass index >30 kg/m2 (OR 1.98, CI 1.22-3.20). CONCLUSION: Extensive measures of antisepsis did not reduce the incidence of SSI. A lapse to adhere to principles of asepsis was identified as an independent risk factor for the development of SSI (ClinicalTrials.gov number, NCT00555815).

Double arterial perfusion strategy for extensive thoracic aortic surgery to avoid lower body hypothermic circulatory arrest

OBJECTIVE To analyse our results of using a double arterial perfusion strategy to avoid lower body hypothermic circulatory arrest after extensive thoracic aortic surgery. METHODS We analysed the intra- and perioperative courses of 10 patients (median age 58 years, median logistic EuroSCORE 14.6) who underwent extensive thoracic aortic surgery with a double arterial perfusion strategy. The main goal of double arterial perfusion is to separate myocardial and supra-aortic from systemic perfusion. Aortic repair starts at the most distal level of the descending aorta, followed by reinsertion of the supra-aortic vessels, and ends with completion of the proximal anastomosis or by any kind of root repair as needed. RESULTS Seven of 10 patients had prior surgery of the thoracic aorta. Indications for surgery were post-dissection aneurysm in 4 patients, true aneurysm in 3, anastomotic aneurysms in 2 and Type B aortic dissection with pseudo-coarctation in 1. Surgical access was performed through median sternotomy with left hemi-clamshell extension in all cases. There was no in-hospital mortality, but perioperative neurological symptoms occurred in 2 patients. These 2 patients developed delayed stroke (after awaking) after an initial uneventful clinical course, and in 1 of them, neurological symptoms resolved completely during follow-up. The median follow-up was 7 (±13) months. There was no death and no need for additional redo surgery during this observational period. CONCLUSIONS Extensive surgery of the thoracic aorta using a double arterial perfusion technique in order to avoid lower body hypothermic circulatory arrest is an attractive option. Further refinements of this technique may enable the safe and effective simultaneous multisegmental treatment of thoracic aortic pathology in patients who would otherwise have to undergo a two-step surgical approach.

Noninvasive electrocardiographic mapping for prediction of tachycardia mechanism and origin of atrial tachycardia following bilateral pulmonary transplantation

This is a case of atrial tachycardia 2 years after pulmonary transplantation. After excluding right atrial involvement, tachycardia origin was located in a scar region medial to the anastomosis of the left inferior pulmonary donor vein. Tachycardia mechanism was microreentry. Noninvasive electrocardiographic mapping performed before the ablation procedure matched with results of invasive Carto mapping and predicted both tachycardia mechanism and origin. We discuss arrhythmia mechanism found after pulmonary transplantation and benefit of noninvasive electrocardiographic mapping for procedure planning.

Is there good simulation basic training for end-to-side vascular microanastomoses?

BACKGROUND Microvascular anastomosis is the cornerstone of free tissue transfers. Irrespective of the microsurgical technique that one seeks to integrate or improve, the time commitment in the laboratory is significant. After extensive previous training on several animal models, we sought to identify an animal model that circumvents the following issues: ethical rules, cost, time-consuming and expensive anesthesia, and surgical preparation of tissues required to access vessels before performing the microsurgical training, not to mention that laboratories are closed on weekends. METHODS Between January 2012 and April 2012, a total of 91 earthworms were used for 150 microsurgical training exercises to simulate vascular end-to-side microanastomosis. The training sessions were divided into ten periods of 7 days. Each training session included 15 simulations of end-to-side vascular microanastomoses: larger than 1.5 mm (n=5), between 1.0 and 1.5 mm (n=5), and smaller than 1.0 mm (n=5). A linear model with the main variables being the number of weeks (as a numerical covariate) and the size of the animal (as a factor) was used to determine the trend in time of anastomosis over subsequent weeks as well as the differences between the different size groups. RESULTS The linear model shows a significant trend (p<0.001) in time of anastomosis in the course of the training, as well as significant differences (p<0.001) between the groups of animals of different sizes. For microanastomoses larger than 1.5 mm, the mean anastomosis time decreased from 19.3±1.0 to 11.1±0.4 min between the first and last week of training (decrease of 42.5%). For training with smaller diameters, the results showed a decrease in execution time of 43.2% (diameter between 1.0 and 1.5 mm) and 40.9% (diameter<1.0 mm) between the first and last periods. The study demonstrates an improvement in the dexterity and speed of nodes execution. CONCLUSION The earthworm appears to be a reliable experimental model for microsurgical training of end-to-side microanastomoses. Its numerous advantages are discussed here and we predict training on earthworms will significantly grow and develop in the near future. LEVEL OF EVIDENCE III This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Outcomes of truncal vascular injuries in children.

BACKGROUND: Pediatric truncal vascular injuries occur infrequently and have a reported mortality rate of 30% to 50%. This report examines the demographics, mechanisms of injury, associated trauma, and outcome of patients presenting for the past 10 years at a single institution with truncal vascular injuries. METHODS: A retrospective review (1997-2006) of a pediatric trauma registry at a single institution was undertaken. RESULTS: Seventy-five truncal vascular injuries occurred in 57 patients (age, 12 +/- 3 years); the injury mechanisms were penetrating in 37%. Concomitant injuries occurred with 76%, 62%, and 43% of abdominal, thoracic, and neck vascular injuries, respectively. Nonvascular complications occurred more frequently in patients with abdominal vascular injuries who were hemodynamically unstable on presentation. All patients with thoracic vascular injuries presenting with hemodynamic instability died. In patients with neck vascular injuries, 1 of 2 patients who were hemodynamically unstable died, compared to 1 of 12 patients who died in those who presented hemodynamically stable. Overall survival was 75%. CONCLUSIONS: Survival and complications of pediatric truncal vascular injury are related to hemodynamic status at the time of presentation. Associated injuries are higher with trauma involving the abdomen.