[Impact of breast dimension in one-stage augmentation mastopexies on implant selection: review of 103 consecutive breast augmentations with nanotextured silicone implants]. / Einfluss der Brustdimension bei der einzeitigen Augmentationsmastopexie auf die Implantatauswahl ­ Erfahrungen aus 103 konsekutiven Brustaugmentationen mit nanotexturierten Silikonimplantaten.

INTRODUCTION: According to current studies, one-stage augmentation mastopexy (AM) is associated with only minor complications and a lower reoperation rate compared with a staged procedure. In AM, breast dimension can differ notably compared with those cases without simultaneous mastopexy. However, these differences have only been insufficiently investigated. This study aims to quantify the differences and then evaluate the effect of breast dimension on implant selection. In addition, it evaluates the influence of mastopexy on the outcome of augmentation mammoplasties with round nanotextured silicone gel implants. PATIENTS AND METHODS: Over a two-year period, all patients with primary augmentation mammoplasties using nanotextured implants were included in the study. Patients' demographic data, breast measurements, specifications of the implants placed, and complications in the breast augmentation group without mastopexy were compared with those of the group with AM. The satisfaction of patients and surgeons was documented using Likert scales. RESULTS: A total of 206 breast augmentations were performed in n = 103 patients. The mean follow-up was 24.0 ±â€…4.3 months. Compared with augmentations without an indication for simultaneous mastopexy, the AM group had wider breast bases and larger preoperative cup sizes; p < 0.001. As a result, implants selected for AM had greater diameters and lower volumes (p < 0.05) and were associated with smaller projections; p < 0.001. The total revision rates after augmentations without (n = 51) and with combined mastopexy (n = 52) were 5.9 % and 19.2 % (p < 0.05), respectively. AM increased tissue-related revisions from 2.0 % to 13.4 % (p < 0.05) without having an impact on implant-related revisions (3.9 % vs. 5.8 %, p = 0.663). The overall incidence of capsular contracture was 1.9 %. Satisfaction levels were approximately equal in both groups. CONCLUSION: In comparison to augmentations without mastopexy, wider breast bases and larger breast volumes before surgery lead to the selection of significantly different implant dimensions in AM. Nanotextured silicone implants are associated with low complication rates, while an increased risk for tissue-related revisions of the combined procedure remains. Further studies are necessary in order to evaluate possible advantages and disadvantages over established implants.

Management of Capsular Contracture in Cases of Silicone Gel Breast Implant Rupture with Use of Pulse Lavage and Open Capsulotomy.

INTRODUCTION: Pulse lavage (PL) irrigation of prosthesis pockets has prior been described for breast implant salvages. However, PL for removal of leaked silicone from prosthesis pockets after implant ruptures has not been studied yet. Since open capsulotomies are regarded as equal treatment of capsular contracture (CC) than capsulectomies, this study analyzed the clinical outcome of PL for silicone removal and subsequent capsulotomy in cases of concurrent CC and breast implant rupture. METHODS: Between 2012 and 2017, 55 patients (75 breasts) with suspected silicone implant rupture and CC (Baker grade III/IV), after primary breast augmentation or implant-based breast reconstruction, were included in a retrospective, observational study. Mean patient follow-up was 12.2 ± 3.6 months. RESULTS: In all preoperatively suspected ruptured silicone breast implants, around a quarter were intact. In contrast to previously published data, implant exchanges in cases of implant ruptures did not lead to significantly higher CC recurrence rates (27.6% vs. 22.2% in cases of intact implants, p = 0.682), if the prosthesis pockets were treated with PL irrigation followed by open capsulotomy. PL reduced the amount of encapsulated silicone remnants histologically. The age of patients with CC after failed implant-based reconstruction was significant lower for salvage surgeries with flap reconstruction than for implant exchanges, p < 0.05. CONCLUSIONS: PL irrigation of prosthesis pockets prior to open capsulotomy is a safe and effective treatment of CC with concurrent silicone leakage. Remaining silicone remnants in breast capsules may affect the development of a recurrent CC. To avoid CC recurrences, patients should consider conversion to autologous tissue. LEVEL OF EVIDENCE IV: 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 .

[Treatment of Sternal Osteomyelitis after Median Sternotomy in 130 Patients with Pedicled Myocutaneous Latissimus Flap]. / Therapie der Sternumosteomyelitis nach medianer Sternotomie bei 130 Patienten mittels gestielter myokutaner Latissimuslappenplastik.

BACKGROUND: After median sternotomy in cardiac surgery, deep sternal wound infections develop in 0.8 - 8% of patients, resulting in prolonged hospital stay and increased morbidity and mortality. Our treatment strategy combines radical surgical debridement, removal of extraneous material and reconstruction of large and deep defects by a pedicled M. latissimus dorsi flap. With retrospective analysis of patient characteristics and pre- und perioperative data we could identify risk factors in regard to proper wound healing and bleeding complications. MATERIAL AND METHODS: Patient characteristics (age, BMI, gender), medical history (diabetes mellitus, chronic obstructive lung disease, renal insufficiency and pre- and perioperative data (anticoagulation, bacterial colonization during reconstruction) were collected for 130 patients treated by latissimus flap to cover sternal wounds between 2009 and 2015. RESULTS: The mean age was 68.72 ± 9.53 years; 37% of patients were female. The in-hospital mortality was 3.8%. Reoperation rate because of wound healing problems was 21.5%; bleeding complications leading to reoperation occurred in 10.8% of all patients. At the point of reconstruction, Staphylococcus (S.) aureus and S. epidermidis were detected most frequently. Age over 80 (p = 0.04), female sex (p = 0.002), detection of fecal bacteria (p = 0.006), or multiresistant bacteria (p = 0.007) and Klebsiellae were regarded as significant risk factors for wound healing problems leading to reoperation after flap surgery. High dose therapy with danaparoid/fondaparinux was a significant risk factor for bleeding complications needing reoperation. CONCLUSION: The pedicled latissimus flap has to be considered as the preferred method in large sternal wounds to achieve sufficient defect filling. The risk of wound healing disruption is significantly influenced by bacteria detected in the sternal wound at the point of reconstructive surgery.

Lipofilling effects after breast cancer surgery in post-radiation patients: an analysis of results and algorithm proposal.

BACKGROUND: Lipofilling or autologous fat transfer is an established technique in plastic surgery. Herein, we describe the lipofilling effects after implant-based breast reconstruction in post-radiation patients and propose an algorithm for indication of lipofilling. METHODS: Forty patients with a history of breast cancer were included in this retrospective analysis. Patients had undergone either breast conserving therapy or mastectomy. Twenty-six patients underwent additional radiation therapy. Patients were assessed using a post-radiation skin scoring classification. RESULTS: In total, 68 lipofilling procedures were analyzed. Scar release, skin softening, improved quality of life, and improvement of post-radiation findings are results of lipofilling with a closed filtration system. In all patients with post-surgical radiation, an improvement of tissue quality was observed. Staging revealed that lipofilling improved mean post-radiation skin scores of 2.40 ± 0.89 to 1.21 ± 0.76 (p ≤ 0.000). There was no recurrence of breast cancer in our study patients. CONCLUSIONS: This study introduces an algorithm using lipofilling in reconstructive breast surgery and especially in post-radiation patients with low risks as well as very high acceptance in patients with various indications for this procedure. A regenerative aspect was also detectable in patients following radiation therapy and reconstruction. Lipofilling is a safe and effective procedure with a low incidence of minor complications. It is therefore a feasible method to resolve volume deficiencies and asymmetric results after oncologic breast surgery. Nevertheless, a prospective study has now been initiated focusing on the oncologic safety of lipofilling including ultrasound and radiological examinations to validate the findings of this initial study. Level of Evidence: Level IV, therapeutic study.

The novel guanylhydrazone CPSI-2364 ameliorates ischemia reperfusion injury after experimental small bowel transplantation.

BACKGROUND: Resident macrophages within the tunica muscularis are known to play a crucial role in initiating severe inflammation in response to ischemia reperfusion injury after intestinal transplantation contributing to graft dysmotility, bacterial translocation, and possibly, acute rejection. The p38 mitogen-activated protein kinase is a key player in the signaling of proinflammatory cytokine synthesis in macrophages. Therefore, we investigated the effects of CPSI-2364, an apparent macrophage-specific inhibitor of the p38 mitogen-activated protein kinase pathway in an isogenic intestinal rat transplantation model. METHODS: Recipient and donor animals were treated perioperatively with CPSI-2364 (1 mg/kg, intravenously) or vehicle solution. Nontransplanted animals served as control. Animals were killed 30 min, 3 hr, and 18 hr after reperfusion. RESULTS: CPSI-2364 treatment resulted in significantly less leukocyte infiltration and significantly improved graft motor function (18 hr). Messenger RNA expression of proinflammatory cytokines (interleukin 6) and kinetic active mediators (NO) was reduced by CPSI-2364 in the early phase after transplantation. Histologic evaluation revealed the protective effects of CPSI-2364 treatment by a significantly less destruction of mucosal integrity at all time points. Perioperative treatment with CPSI-2364 improves graft motor function through impaired inflammatory responses to ischemia reperfusion injury by inhibition of proinflammatory cytokines and suppression of nitric oxide production in macrophages. CONCLUSIONS: CPSI-2364 presents as a promising complementary pharmacological approach preventing postoperative dysmotility for clinical intestinal transplantation.

A natural tetrahydropyrimidine, ectoine, ameliorates ischemia reperfusion injury after intestinal transplantation in rats.

BACKGROUND/AIMS: Ischemia reperfusion (I/R) injury after small bowel transplantation leads to inflammatory reactions and loss of structural integrity with subsequent graft contractile dysfunction in the early postoperative phase. The natural tetrahydropyrimidine ectoine (1-,4-,5-,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid; THP) protects the ileal mucosa and muscularis against effects of I/R injury in an experimental model of isolated graft reperfusion. The effects of THP treatment were evaluated in an established experimental intestinal transplant model. METHODS: Isogenic, orthotopic small bowel transplantation was performed in Lewis rats (6 h cold ischemia time). Perioperative THP treatment (intraluminal/intravascular) groups were compared to vehicle-treated animals (after 3 and 24 h) and non-transplanted controls (n = 5/group). Park's score defined the effects of I/R injury. The infiltration of neutrophils, monocytes and macrophages, mRNA expression of IL-6 and TNF-α, serum levels of IL-6 and NO and smooth muscle contractility were evaluated. RESULTS: Improved graft outcome after intraluminal and intravascular THP treatment was defined by considerably ameliorated neutrophil infiltration and less histological signs of I/R injury (p ≤ 0.05). In the presence of THP, mRNA expression of IL-6 and TNF-α and IL-6 and NO serum levels were reduced and smooth muscle function was improved. CONCLUSION: THP treatment offers protection against the effects of I/R injury in intestinal transplantation in vivo, however, only as supplementary treatment option.

Orthotopic small bowel transplantation in rats.

Small bowel transplantation has become an accepted clinical option for patients with short gut syndrome and failure of parenteral nutrition (irreversible intestinal failure). In specialized centers improved operative and managing strategies have led to excellent short- and intermediate term patient and graft survival while providing high quality of life (1,3). Unlike in the more common transplantation of other solid organs (i.e. heart, liver) many underlying mechanisms of graft function and immunologic alterations induced by intestinal transplantation are not entirely known(6,7). Episodes of acute rejection, sepsis and chronic graft failure are the main obstacles still contributing to less favorable long term outcome and hindering a more widespread employment of the procedure despite a growing number of patients on home parenteral nutrition who would potentially benefit from such a transplant. The small intestine contains a large number of passenger leucocytes commonly referred to as part of the gut associated lymphoid system (GALT) this being part of the reason for the high immunogenity of the intestinal graft. The presence and close proximity of many commensals and pathogens in the gut explains the severity of sepsis episodes once graft mucosal integrity is compromised (for example by rejection). To advance the field of intestinal- and multiorgan transplantation more data generated from reliable and feasible animal models is needed. The model provided herein combines both reliability and feasibility once established in a standardized manner and can provide valuable insight in the underlying complex molecular, cellular and functional mechanisms that are triggered by intestinal transplantation. We have successfully used and refined the described procedure over more than 5 years in our laboratory (8-11). The JoVE video-based format is especially useful to demonstrate the complex procedure and avoid initial pitfalls for groups planning to establish an orthotopic rodent model investigating intestinal transplantation.

Combination therapy of tacrolimus and infliximab reduces inflammatory response and dysmotility in experimental small bowel transplantation in rats.

BACKGROUND: Intestinal transplantation initiates a functionally relevant inflammatory response by activation of resident macrophages within the muscularis associated with dysmotility. Infliximab is used successfully as a potent anti-inflammatory agent for the treatment of chronic inflammatory bowel diseases and as rescue therapy in acute steroid-resistant rejection in selected settings in clinical small bowel transplantation. We hypothesize that additional perioperative treatment with infliximab diminishes initiation of the inflammatory cascade and improves motility in small bowel grafts using a standard tacrolimus immunosuppressive protocol. METHODS: Orthotopic intestinal transplantation was performed in rats. In two treatment groups (24/168 hr), infliximab was administered intravenously directly after reperfusion and tacrolimus was injected intramuscularly after transplantation and once a day. Two other treatment groups (24/168 hr) received standard immunosuppressive therapy with tacrolimus. Isogenic and allogenic transplanted vehicle-treated animals (24/168 hr) and native gut served as control. RESULTS: Infliximab-treated grafts exhibited significantly less leukocyte infiltration at 24/168 hr after transplantation and at 168 hr significantly less apoptosis in the tunica muscularis compared with tacrolimus monotherapy. Additional infliximab treatment resulted in increased smooth muscle contractility (30%) after 24 hr compared with tacrolimus control. CONCLUSIONS: Dysmotility of transplanted small bowel results from reperfusion injury and acute rejection. Additional perioperative treatment with infliximab reduces early unspecific inflammatory responses and complements immunosuppressive therapy with tacrolimus.

Preoperative short-term parenteral administration of polyunsaturated fatty acids ameliorates intestinal inflammation and postoperative ileus in rodents.

PURPOSE: Abdominal surgery results in an inflammation of the intestinal muscularis externa (ME), subsequently leading to postoperative ileus (POI). Polyunsaturated fatty acids (PUFA) are known to modulate inflammation. The aim of this study was to analyze the effect of preoperative parenteral administration of marine (n-3) or soybean (n-6) PUFA lipid emulsions (PUFA-LE) on POI and tissue fatty acid profiles. METHODS: Rodents underwent intestinal manipulation (IM) after 5 days of parenteral administration of 10-mL/kg body weight saline, (n-3), or (n-6) PUFA-LE. Sham animals received saline treatment without IM. In rats, postoperative inflammation was quantified by ME neutrophil levels and NO production in organ culture, and ME function was determined by an in vitro contractility measurement. Additionally, in vivo gastrointestinal transit (GIT) was analyzed in mice. Lipopolysaccharide-induced IL-6 expression of rat bone marrow-derived mononuclear cells and ME was analyzed. Fatty acids were measured by gas chromatography in rat blood, bone marrow cells, and ME. RESULTS: The (n-3) PUFA-LE reduced neutrophil levels and NO production after IM and improved in vitro jejunal contractility and GIT time. The (n-6) PUFA-LE significantly reduced postoperative inflammation and tended to improve intestinal motility (P < 0.06). Interestingly, (n-6) PUFA-LE significantly reduced the levels of arachidonic acid in ME (-63%), while (n-3) PUFA-LE reduced arachidonic acid (-20%) and additionally raised EPA (+550%). CONCLUSION: Short-term preoperative parenteral administration of (n-3) or (n-6) PUFA-LE significantly alters tissue-specific fatty acid profiles. Preoperative parenteral PUFA-LE supplementation, preferably by marine (n-3) PUFA, ameliorates postoperative intestinal inflammation and dysmotility and could be a promising therapeutic option in POI prophylaxis.

Effects of immunosuppressive therapy after experimental small bowel transplantation in rats.

Significant improvements of graft and patient survival have been achieved over the past 20 years in the field of intestinal transplantation. Tacrolimus monotherapy with corticosteroids, or in combination with sirolimus is the most commonly used immunosuppressive regimen. Early (24h) after experimental allogenic small bowel transplantation in rats, sirolimus reduces the cellular and molecular inflammatory response with subsequent graft dysmotility more efficiently than tacrolimus, with contrary effects at 7 days after transplantation. This study evaluates three immunosuppressive strategies in the post-acute phase after intestinal transplantation - tacrolimus or sirolimus monotherapy and the combination therapy of tacrolimus with infliximab. After orthotopic intestinal transplantation between Brown Norway and Lewis rats, animals received 14 days of immunosuppressive treatment. Histology, infiltration of neutrophils, monocytes and macrophages, cytokine and mediator mRNA expression (real time RT-PCR) and smooth muscle function in a standard organ bath were assessed at 14 days after transplantation in all treatment groups and isogenic controls. Allogenic transplanted rats without immunosuppressive therapy and non-transplanted animals served as further control. Tacrolimus prevented acute rejection and graft dysmotility more effectively (p ≥ 0.05) than sirolimus. Reduced mRNA expression levels of CD4, IFN-γ, IL-6, IL-10, iNOS, NFκB, TNF-α and MCP-1 (p ≤ 0.05) were observed in tacrolimus treated animals compared to sirolimus. Additional infliximab application did not influence the cellular and molecular inflammatory response in the post-acute phase after transplantation. In conclusion, the severe cellular and molecular inflammatory response in allogenic transplanted grafts without immunosuppressive therapy is ameliorated by all three immunosuppressive regimens, but tacrolimus was found to be more efficient than sirolimus at 14 days after transplantation. Our findings do not rule out the usage of sirolimus as single immunosuppressive therapy, but indicate and confirm the potency and effectivity of tacrolimus as basis immunosuppressant in the field of intestinal transplantation.

Inducible nitric oxide synthase expression in the intestinal muscularis mediates severe smooth muscle dysfunction during acute rejection in allogenic rodent small bowel transplantation.

BACKGROUND: Acute rejection in small bowel transplantation is associated with dysmotility. Therefore, host and organ not only face the threat of destructive immunological processes but also the risk of bacterial translocation, endotoxemia, and systemic inflammatory response syndrome. We hypothesized that dysmotility during acute rejection is based on an alloreactive leukocyte infiltrate and coexpression of the kinetically active mediator inducible nitric oxide synthase (iNOS) in the muscularis propria. MATERIALS AND METHODS: Allogenic and isogenic rat small bowel transplantation (SBTx; Brown Norway [BN] to Lewis and BN to BN) was performed without immunosuppression. Animals were sacrificed 4 and 7 d after SBTx. Leukocyte infiltration and iNOS protein was investigated by immunohistochemistry and immunohistology. Real-time reverse transcription polymer chain reaction was used to detect iNOS expression. Griess reaction was used to evaluate NO production. Spontaneous, bethanechol-stimulated, and L-N(6)-(1-iminoethyl)-L-Lysin-blocked jejunal circular muscle contractions were measured in a standard organ bath in vitro. RESULTS: On d 7 after SBTx, allogenic transplanted animals showed significant infiltration with ED-1- and ED-2-positive monocytes and macrophages within the muscularis parallel to the manifestation of acute rejection. Additionally, immunohistochemistry localized iNOS protein in leukocytes within the muscularis. Reverse transcription polymer chain reaction showed a significant increase in iNOS mRNA expression (460-fold) in allogenic transplanted muscularis compared to isogenic transplanted muscularis (2.5-fold). Compared to controls, allogenic grafts showed a 73% decrease in smooth muscle contractility, while isogenic grafts showed only an 8% decrease of contractility on d 7. L-N(6)-(1-iminoethyl)-L-Lysin application in vitro significantly improved muscle contractility and decreased NO production. CONCLUSION: The data show that inflammation associated iNOS expression in the intestinal graft muscularis is involved in motoric graft dysfunction during acute rejection.

Role of resident macrophages in the immunologic response and smooth muscle dysfunction during acute allograft rejection after intestinal transplantation.

Resident muscularis macrophages initiate an inflammatory cascade during ischemia/reperfusion that is associated with dysmotility and the activation of immunologic processes. We hypothesized that these muscularis macrophages may also play a potential immunologic role for acute allograft rejection in intestinal transplantation. Orthotopic SBTx (BN-Lew) was performed without immunosuppression. Animals were sacrificed 7 days after SBTx. The role of resident macrophages was evaluated by transplantation of macrophage-depleted and gadolinium chloride-treated gut. Leukocyte infiltration was investigated in muscularis whole mounts by immunohistochemistry. Mediator mRNA expression was determined by Real-Time-RT-PCR. Apoptosis was evaluated by TUNEL. Smooth muscle contractility was assessed in a standard organ bath. In comparison to vehicle-treated grafts, macrophage-depleted grafts exhibited significantly lower mediator mRNA peak expression (IL-6, IL-2, IL-10, MCP-1, iNOS, TNFalpha, IFNgamma, FasL), leukocyte infiltrates (ED1- and ED2 positive monocytes and macrophages, neutrophils, CD4(+) and CD8(+) lymphocytes), apoptosis rates and an improved histologic rejection grading. Vehicle-treated grafts showed a 77% decrease in smooth muscle contractility compared to naïve controls, while macrophage-depleted gut exhibited only a 51% decrease in contractile activity. Transplantation of macrophage-depleted gut attenuates the functionally relevant molecular and cellular immunologic response within the graft muscularis in acute allograft rejection. Resident macrophages participate in initiating these processes.

Exogenous surfactant application in a rat lung ischemia reperfusion injury model: effects on edema formation and alveolar type II cells.

BACKGROUND: Prophylactic exogenous surfactant therapy is a promising way to attenuate the ischemia and reperfusion (I/R) injury associated with lung transplantation and thereby to decrease the clinical occurrence of acute lung injury and acute respiratory distress syndrome. However, there is little information on the mode by which exogenous surfactant attenuates I/R injury of the lung. We hypothesized that exogenous surfactant may act by limiting pulmonary edema formation and by enhancing alveolar type II cell and lamellar body preservation. Therefore, we investigated the effect of exogenous surfactant therapy on the formation of pulmonary edema in different lung compartments and on the ultrastructure of the surfactant producing alveolar epithelial type II cells. METHODS: Rats were randomly assigned to a control, Celsior (CE) or Celsior + surfactant (CE+S) group (n = 5 each). In both Celsior groups, the lungs were flush-perfused with Celsior and subsequently exposed to 4 h of extracorporeal ischemia at 4 degrees C and 50 min of reperfusion at 37 degrees C. The CE+S group received an intratracheal bolus of a modified natural bovine surfactant at a dosage of 50 mg/kg body weight before flush perfusion. After reperfusion (Celsior groups) or immediately after sacrifice (Control), the lungs were fixed by vascular perfusion and processed for light and electron microscopy. Stereology was used to quantify edematous changes as well as alterations of the alveolar epithelial type II cells. RESULTS: Surfactant treatment decreased the intraalveolar edema formation (mean (coefficient of variation): CE: 160 mm3 (0.61) vs. CE+S: 4 mm3 (0.75); p < 0.05) and the development of atelectases (CE: 342 mm3 (0.90) vs. CE+S: 0 mm3; p < 0.05) but led to a higher degree of peribronchovascular edema (CE: 89 mm3 (0.39) vs. CE+S: 268 mm3 (0.43); p < 0.05). Alveolar type II cells were similarly swollen in CE (423 microm3(0.10)) and CE+S (481 microm3(0.10)) compared with controls (323 microm3(0.07); p < 0.05 vs. CE and CE+S). The number of lamellar bodies was increased and the mean lamellar body volume was decreased in both CE groups compared with the control group (p < 0.05). CONCLUSION: Intratracheal surfactant application before I/R significantly reduces the intraalveolar edema formation and development of atelectases but leads to an increased development of peribronchovascular edema. Morphological changes of alveolar type II cells due to I/R are not affected by surfactant treatment. The beneficial effects of exogenous surfactant therapy are related to the intraalveolar activity of the exogenous surfactant.

Reduced vascular endothelial growth factor correlates with alveolar epithelial damage after experimental ischemia and reperfusion.

BACKGROUND: After clinical lung transplantation, the amount of vascular endothelial growth factor (VEGF) was found to be decreased in the bronchoalveolar lavage from lungs with acute lung injury. Since Type II pneumocytes are a major site of VEGF synthesis, VEGF depression may be an indicator of pulmonary epithelial damage after ischemia and reperfusion. METHODS: Using an established rat lung model, we investigated the relationship between VEGF protein expression, oxygenation capacity and structural integrity after extracorporeal ischemia and reperfusion (ischemia 6 hours at 10 degrees C, reperfusion 50 minutes) and preservation with either low-potassium dextran solution (Perfadex 40 kD, n = 8) or Celsior (n = 6). Untreated, non-ischemic lungs served as controls (n = 5 per group). Perfusate oxygenation was recorded during reperfusion. An enzyme-linked immunoassay (ELISA) for VEGF protein and reverse transcription-polymerase chain reaction (RT-PCR) for mRNA splice variants were determined on tissue collected from the left lungs, whereas the right lungs were fixed by vascular perfusion for VEGF immunohistochemistry as well as structural analysis by light and electron microscopy. Tissue collection by systematic uniform random sampling was representative for the whole organ and allowed for quantification of structures by stereological means. RESULTS: After ischemia and reperfusion, the 3 major VEGF isoforms, VEGF(120), VEGF(164) and VEGF(188), were present. VEGF protein expression was reduced, which correlated significantly with perfusate oxygenation (r = 0.736; p = 0.002) at the end of reperfusion. It was inversely related to Type II cell volume (r = 0.600; p = 0.047). VEGF protein was localized by immunohistochemistry in Type II pneumocytes, alveolar macrophages as well as bronchial epithelium, and staining intensity of Type II cells was reduced after ischemia and reperfusion. Alveolar edema did not occur but significant interstitial edema accumulated around vessels and in the blood-gas barrier, which showed a higher degree of epithelial damage after preservation with Celsior compared with the other groups. CONCLUSIONS: Depression in VEGF protein expression can be considered an indicator for increased alveolar epithelial damage. Preservation with low-potassium dextran solution resulted in improved oxygenation and tissue integrity compared with Celsior.

Experimental lung preservation with Perfadex: effect of the NO-donor nitroglycerin on postischemic outcome.

OBJECTIVE: Optimal preservation of postischemic graft function is essential in lung transplantation. Antegrade flush perfusion with modified Euro-Collins solution represents the standard technique worldwide. However, growing evidence suggests the superiority of extracellular-type Perfadex solution (Vitrolife AB, Gothenburg, Germany) over Euro-Collins solution. During ischemia and reperfusion, endogenous pulmonary nitric oxide synthesis is decreased, and therefore therapeutic stimulation of the nitric oxide pathway might be beneficial in ameliorating ischemia-reperfusion damage. However, research mainly focuses on nitric oxide supplementation of intracellular solutions, and no studies exist in which the effect of nitroglycerin on Perfadex preservation quality is evaluated. METHODS: Eight rat lungs each were preserved with Perfadex solution with or without nitroglycerin (0.1 mg/mL) and compared with low-potassium Euro-Collins solution. Postischemic lungs were reventilated and reperfused, and oxygenation capacity, pulmonary vascular resistance, and peak inspiratory pressures were monitored continuously. Stereological analysis was used for evaluation of pulmonary edema and assessment of the vasculature. Statistics were performed by using different analysis of variance models. RESULTS: The oxygenation capacity of the Perfadex-preserved groups was higher compared with that of the low-potassium Euro-Collins solution group (P <.03). By using nitroglycerin, flush-perfusion time was reduced, and Perfadex solution with nitroglycerin-protected lungs showed superior oxygenation capacity compared with that seen in Perfadex solution-protected organs (P <.01). Furthermore, pulmonary vascular resistance and peak inspiratory pressures were improved in the nitroglycerin group (P <.01). Stereology revealed comparable intrapulmonary edema between groups and a trend toward less vasoconstricted vasculature in Perfadex with nitroglycerin-protected lungs. CONCLUSIONS: Perfadex solution provides superior lung preservation in terms of postischemic oxygenation capacity than Euro-Collins solution. Supplementation of the nitric oxide pathway by nitroglycerin further enhances functional outcome of Perfadex-preserved organs and might be an easily applicable tool in clinical lung transplantation.