Management strategies for the open abdomen: survey of the American Association for the Surgery of Trauma membership.

PURPOSE: The purpose of this study is to report results from a survey of members of the American Association for the Surgery of Trauma (AAST) on strategies for management of the open abdomen. MATERIAL AND METHODS: Invitations to participate in a web-based survey were sent to AAST members via email. MAIN RESULTS: The response rate was 26%. For 74% of surgeons surveyed, the number of cases treated per year has increased over the last 10 years. The abdomen is left open for damage control (46% of respondents) and abdominal organ distention (22%). Most respondents use the vacuum pack system to temporarily close the abdomen (57%) and a smaller proportion use a bogota bag (18%). Ventilatory failure was the most frequent complication (72%) and elderly patients have the worse outcome. SIGNIFICANT CONCLUSIONS: Given the lack of consensus regarding optimal management strategies for the open abdomen, there is a need for prospective, multi-institutional studies to evaluate therapeutic approaches to treat this challenging problem.

Standing surgical repair of propagating metacarpal and metatarsal condylar fractures in racehorses.

REASONS FOR PERFORMING STUDY: Repair of spiral and long diaphyseal metacarpal and metatarsal fractures under anaesthesia can be problematic and associated with a high incidence of complications, including fracture propagation necessitating euthanasia. OBJECTIVE: To report on a practical repair technique for which general anaesthesia is not required. METHODS: Thirteen racehorses with a spiral/propagating condylar fracture had the fracture repaired using local anaesthesia and sedation, without the need for general anaesthetic. RESULTS: Ten of the horses returned to training and 8 raced again. Two horses were retired directly to stud. One horse had propagation of the fracture 3 days post surgery, and was subjected to euthanasia. CONCLUSIONS AND POTENTIAL RELEVANCE: Results achieved were comparable to those gained using standard repair techniques under general anaesthesia. The described technique removes the need for general anaesthesia for repair of selected condylar fractures.

In vivo transtracheal adenovirus-mediated transfer of human interleukin-10 gene to donor lungs ameliorates ischemia-reperfusion injury and improves early posttransplant graft function in the rat.

We examined the effect of adenovirus-mediated transtracheal transfer of the human interleukin 10 (hIL-10) gene on lung ischemia-reperfusion (IR) injury, which is the insult due to hypothermic preservation plus graft reperfusion, and posttransplant lung function in Lewis rat lungs. Thirty rats were divided into 6 groups (n = 5). Groups 1 and 4 received 5 x 10(9) PFU of Ad5E1RSVhIL-10, groups 2 and 5 received 5 x 10(9) PFU of Ad5BGL2 ("empty" vector), and groups 3 and 6 received 3% sucrose (diluent). After 24 hr of in vivo transfection, lungs were stored at 4 degrees C (cold ischemic time, CIT) for 6 hr (groups 1-3) or 24 hr (groups 4-6) before transplantation. After 2 hr of reperfusion, lung function was assessed by oxygenation (FIO2, 1.0), airway pressure (AwP), and wet-to-dry (W/D) weight ratios. Rat tumor necrosis factor alpha (rTNF-alpha), interferon gamma (IFN-gamma), IL-10, and hIL-10 were measured in graft tissue and recipient plasma by ELISA and detected by immunohistochemistry (IHC). Partial pressure of oxygen (PaO2) levels in the hIL-10 group (6 hr of CIT) were higher than in empty vector and diluent groups (PaO2, 530 +/- 23 vs. 387 +/- 31 and 439 +/- 27 mmHg, respectively, p < 0.05). IL-10 rats after 24 hr of CIT showed higher PaO2 levels (260 +/- 29 mmHg) than empty vector (96 +/- 24 mmHg) or diluent (133 +/- 10 mmHg) lungs (p < 0.05). AwP and W/D ratios were reduced in hIL10 lungs (p < 0.05) compared with the other groups. rTNF-alpha and INF-gamma were reduced in tissue and plasma in groups 1 and 4 (p < 0.05). rIL-10 was reduced in the tissue of hIL-10 lungs (p < 0.05). IHC showed equal distribution of cytokines in tissue and abundant transgene expression in large and small airway epithelium in hIL-10 lungs.

Ultrasound appearance of an equine testicular seminoma.

A 16-year-old thoroughbred stallion developed sudden swelling of the left testicle. The stallion had previously been regarded as a unilateral cryptorchid. Ultrasound examination of the left testicle revealed a diffusely heterogeneous parenchyma. The testicle was diffusely hypoechoic with ill defined regions of hyperechogenicity giving the appearance of hypoechoic nodules throughout the testicular parenchyma. No normal testicular tissue was identifiable. An echogenic band, representing a pseudocapsule could be seen surrounding the testicle. Histopathologic diagnosis a seminoma.

Raffinose improves 24-hour lung preservation in low potassium dextran glucose solution: a histologic and ultrastructural analysis.

BACKGROUND: We have previously shown that the addition of raffinose to low potassium dextran (LPD) preservation solution improves transplanted rat lung function after 24 hours of storage. The mechanisms by which raffinose acts are unclear. The aim of this study was to examine the histologic and ultrastructural correlates of this enhanced pulmonary function after preservation with raffinose. METHODS: In a randomized, blinded study, rat lungs were flushed with LPD, or LPD containing 30 mmol/L of raffinose, and stored for 24 hours at 4 degrees C. Control lungs were flushed with LPD but not stored (n = 5 each group). Changes in postpreservation edema were determined. In addition, lungs were flushed with a trypan blue solution to quantify cell death, and examined using both light and electron microscopy. RESULTS: The LPD lungs gained significantly more weight (25.5%+/-5.5%) compared with raffinose-LPD lungs (5.2%+/-5.3%; p < 0.0001). There were higher percentages of dead cells in the LPD lungs (29%+/-0.3% of total cells) compared with raffinose-LPD lungs (14%+/-1.4%; p < 0.001) and control lungs (0.2%+/-5%; p < 0.001). Control lungs maintained normal ultrastructure, whereas LPD lungs showed a decreased number of intact type II pneumocytes and significant cellular necrosis. Interstitial and alveolar edema with interstitial macrophage infiltration was also observed. Alveolar capillaries were collapsed. In contrast, raffinose-LPD lungs showed only mild alterations such as minimal interstitial edematous expansion, fewer damaged cells, and minimal capillary injury. CONCLUSIONS: Raffinose exerts a cytoprotective effect on pulmonary grafts during preservation, which explains the previously documented improved function. This simple modification of LPD with raffinose may provide clinical benefit in extended pulmonary preservation.

Dynamic changes in apoptotic and necrotic cell death correlate with severity of ischemia-reperfusion injury in lung transplantation.

Ischemia-reperfusion (IR) injury is a major cause of organ dysfunction following lung transplantation. We have recently described increased apoptosis in transplanted human lungs after graft reperfusion. However, a direct correlation between ischemic time, cell death, and posttransplant lung function has not yet been demonstrated. We hypothesized that an increased ischemic period would lead to an increase in cell death, and that the degree and type of cell death would correlate with lung function. To investigate this, we preserved rat lungs at 4 degrees C for 20 min and 6, 12, 18, and 24 h, and then transplanted the lungs and reperfused them for 2 h. Cell viability was determined with a triple staining technique combining trypan blue, terminal deoxynucleotidyl transferase-uridine nucleotide end-labeling, and propidium iodide nuclear staining. Percentages of apoptotic and necrotic cells were calculated from total cell numbers. Following 20 min and 6 and 12 h of cold preservation, less than 2% of graft cells were dead, whereas after 18 and 24 h of cold preservation, 11% and 27% of cells were dead (p < 0.05), the majority of which were necrotic. After transplantation and reperfusion, the mode of cell death changed significantly. In the 6- and 12-h groups, approximately 30% of cells were apoptotic and < 2% were necrotic, whereas in the 18- and 24-h groups, 21% and 29% of cells, respectively, were necrotic and less than 1% were apoptotic. Lung function (Pa(O(2))) decreased significantly (p < 0.05) with increasing preservation time. The percentage of necrotic cells was inversely correlated with posttransplant graft function (p < 0.0001). The study demonstrates a significant association among cold preservation time, extent and mode of cell death, and posttransplant lung function, and suggests new potential strategies to prevent and treat IR injury.

RANTES plays an important role in the evolution of allograft transplant-induced fibrous airway obliteration.

Although lung transplantation is a widely applied therapeutic modality for end-stage pulmonary disease, the long-term survival following this procedure is limited by the development of bronchiolitis obliterans (BO). We investigated the role of RANTES, a C-C chemokine, in the evolution of fibrous airway obliteration (FAO) using a rat heterotopic tracheal transplant model. RANTES was highly expressed in infiltrating mononuclear cells in both allogeneic and isogeneic grafts as revealed by immunohistochemistry. Using a miniosmotic pump, neutralizing anti-RANTES antibody was locally and continuously infused to allografts, whereas recombinant rat RANTES was administered to isografts. Anti-RANTES antibody treatment decreased the number of CD4(+) infiltrating cells in allotracheas and preserved luminal patency compared with those of allocontrols. However, RANTES infusion in isografts did not induce FAO, even though CD4(+) cell migration was increased by this treatment. It appears that RANTES is relevant to the recruitment of CD4(+) cells and the development of FAO in the process of allorejection. Local administration of anti-RANTES might be a therapeutic option for BO following lung transplantation.

Inhibition of angiotensin-converting enzyme by captopril: a novel approach to reduce ischemia-reperfusion injury after lung transplantation.

OBJECTIVES: Ischemia-reperfusion injury after lung transplantation involves the generation of free radicals. Captopril has been shown to be protective in models of ischemia-reperfusion injury in other organs by acting as a free radical scavenger. The purpose of this study was to assess the protective effects of captopril against ischemia-reperfusion injury and to evaluate the ability of captopril to scavenge free radicals and inhibit neutrophil activation in an experimental model of lung transplantation. METHODS: A rat single-lung transplant model was used. Donor lungs were flushed and preserved in low-potassium dextran-glucose solution with (n = 5) and without captopril (500 micromol/L; n = 5) for 18 hours at 4 degrees C and then transplanted and reperfused for 2 hours. At the conclusion of the 2-hour reperfusion period, arterial blood gases, blood pressure, and peak airway pressure were measured. Lung tissue biopsy specimens were obtained for assessment of wet/dry weight ratios, histology, and neutrophil sequestration (myeloperoxidase activity). Lipid peroxidation (F(2)-isoprostane assay) was analyzed from plasma samples and tissue lysates. RESULTS: The addition of captopril to the lung preservation solution significantly improved postreperfusion PO (2) (312 +/- 63.3 mm Hg vs 202 +/- 21.1 mm Hg; P =.006), peak airway pressure (11.4 +/- 1.1 cm H(2)O vs 15.6 +/- 1.5 cm H(2)O; P =.001), and wet/dry weight ratio (4.9 +/- 0.4 vs 15.8 +/- 10.9; P =.008). Blood pressures did not differ significantly between groups. No significant differences were seen in myeloperoxidase activity or F(2)-isoprostane levels. CONCLUSIONS: The use of captopril in the preservation solution ameliorates ischemia-reperfusion injury in transplanted lungs after an extended cold preservation period. The mechanisms by which captopril is protective remain elusive but do not appear to include inhibition of neutrophil sequestration or lipid peroxidation. This novel approach to ischemia-reperfusion injury may lead to improved lung function after transplantation and provide further insight into the pathogenesis of acute lung injury.

Prospective double-blind randomised study of a new regimen of pre-emptive analgesia for inguinal hernia repair: evaluation of postoperative pain course.

OBJECTIVE: To evaluate the effectiveness of a new regimen of pre-emptive analgesia on the development of postoperative pain after inguinal hernia repair. DESIGN: Prospective, double-blind, randomised study. SETTING: University Hospital, Germany. SUBJECTS: 70 consecutive patients who had primary unilateral inguinal hernia repairs. INTERVENTIONS: A new regimen of pre-emptive analgesia with bupivacaine that was infiltrated preoperatively, intraoperatively, and postoperatively was tested. The control group were given saline infiltrations at the same times. Pain was measured up to postoperative day 30 using the visual analogue scale (VAS), the verbal rating scale (VRS), and by recording patient-controlled use of ibuprofen suppositories. RESULTS: Pain was significantly less in the pre-emptive analgesia group than in the control group during the first 10 days postoperatively as assessed by VAS and VRS (p < 0.05). Analgesic consumption was also significantly reduced in the pre-emptive analgesia group (p < 0.05). Multivariate analysis showed that bupivacaine infiltration (pre-emptive analgesia) was associated with significantly less postoperative pain (p < 0.0001). CONCLUSION: This regimen of pre-emptive analgesia is an effective and safe method of reducing postoperative pain and analgesic consumption after inguinal hernia repair.

Targeting the angiotensin system in posttransplant airway obliteration: the antifibrotic effect of angiotensin converting enzyme inhibition.

The angiotensin system plays a role in the pathogenesis of fibrotic diseases. We used a rat heterotopic tracheal transplant model of bronchiolitis obliterans (BO) to examine the role of angiotensin converting enzyme (ACE) in development of the fibroproliferative lesion of BO. Isograft and allograft tracheal transplants were performed. Allograft rats received either no treatment (control) or captopril (100 mg/kg/d) in their drinking water. The drug treatment given to the recipient rats was begun 5 days before transplantation, on postoperative Day 1, or on postoperative Day 5. The treatment was continued until postoperative Day 21, when tracheal specimens were harvested and subjected to histologic, immunohistologic, and morphometric analyses. We noted heavy staining for ACE in the obliterated portion of the tracheas of allograft control animals. This area was not present in nontransplanted or isograft tracheas. Captopril administration begun 5 d before transplantation and on postoperative Day 1 resulted in a significant attenuation in the percent airway obliteration (45% and 26%, respectively) as compared with that in control allografts (83%; p < 0.05). This study demonstrates the presence of ACE in the fibroproliferative lesion in a rat model of BO, and shows that inhibition of ACE can limit development of airway obliteration.

Superior check ligament desmotomy for treatment of superficial digital flexor tendonitis in thoroughbred and standardbred horses.

Bilateral superior check ligament desmotomy was performed on 31 Thoroughbred and 17 Standardbred horses as the sole method of treatment for superficial digital flexor tendonitis. Horses resumed racing between 6 and 19 months after surgery. Horses that were able to compete in 5 or more races without injury to the tendon again were considered to have had a successful return to racing. Twenty-five Thoroughbreds were suitable for later study and 13 of these (52%) raced on 5 or more occasions. Fifteen Standardbreds were suitable for later study and 10 of these (66%) raced on 5 or more occasions. Within the racing industry it is generally thought that about 20 to 30% of horses with superficial digital flexor tendonitis can return to racing after a prolonged rest. The results of this study suggest that bilateral superior check ligament desmotomy may improve the prognosis for a horse returning to racing after injury to the superficial digital flexor tendon.

Changes in luteinizing hormone bioactivity associated with gonadotrophin pulses in the cycling mare.

Equine plasma luteinizing hormone (LH) possesses both biological (in vitro bioassay, B) and immunological (radioimmunoassay, I) activities and the ratio of B:I varies with stage of the oestrous cycle. To estimate the contribution made by pituitary secretion and peripheral metabolism to changes in the B:I ratio, pituitary venous effluent and circulating plasma from 5 dioestrous and 2 oestrous mares were analyzed using both an in vitro bioassay and a radioimmunoassay. During dioestrus, LH was released in a pulsatile fashion with a frequency of 1.4 pulses/24 h and a pulse duration of 20-40 min (centrally) or 2-4 h (peripherally). Between pulses, further secretion of LH from the pituitary was undetectable. During spontaneous pulses, the B:I ratio increased as much as 2- to 3-fold and remained elevated for at least 1 h. A low dose of 10 ng/kg bodyweight (bwt) of the GnRH agonist Buserelin provoked similar changes, unless the exogenous stimulus was close to an endogenous LH discharge. A high dose (50 micrograms) of Buserelin reduced the B:I ratio significantly, in spite of a massive LH release. Samples taken from mares during oestrus showed constantly elevated B:I ratios, a consequence of much greater LH pulse frequency.

Use of iohexol for myelography in the horse.

The use of iohexol as a contrast agent for myelography is reported in two groups of horses. Group 1 (n = 6) were used only for myelography and to assess the clinical and pathological effects of intrathecal administration of iohexol. A volume of 20 ml at a concentration of 300 or 350 mg iodine/ml gave satisfactory myelographic detail with no serious clinical or neurological side effects. Only a minimal inflammatory response could be demonstrated in cerebrospinal fluid at four and 14 days after injection. At post mortem examination 14 days after myelography there was no evidence of meningitis nor was any other pathological change detected. Group 2 (n = 19) comprised a series of clinical cases of suspected cervical vertebral malformation. The only untoward sequelae recorded involved two horses in which iohexol was diluted with sterile water prior in intrathecal injection. A progressive necrotising meningitis developed in both cases which necessitated euthanasia. It was concluded that the major advantages of iohexol for use in the horse were its diagnostic quality, safety and low cost.

Changes in maternal hormone concentrations associated with induction of fetal death at day 45 of gestation in mares.

Pregnant Standardbred mares were allocated to 2 groups. On Day 45 of gestation, 20-45 ml saline (240 g NaCl/l) were injected into the fetal sacs of 10 mares, and the other 10 mares were given sham treatment. Post-operative plasma oestrone sulphate concentrations were lower (P less than 0.01) on Days 48-55 in saline-treated mares than in sham-treated mares. Mean plasma progesterone profiles were similar in the two groups of mares, although post-operative luteolysis occurred in 4 saline-treated mares. There was no difference in plasma CG profiles between the 2 groups, except that CG concentrations in saline-treated mares were generally lower than those of sham-treated mares. There was generally a post-operative loss of uterine and cervical tone in saline-treated mares. These results show that the maintenance of maternal plasma oestrone sulphate concentrations requires the presence of a viable embryo and confirm that luteolysis can occur despite high plasma CG concentrations after fetal death.

Attempted conversion of twin to singleton pregnancy in two mares with associated changes in plasma oestrone sulphate concentrations.

The removal of one of twin embryos was attempted by infusion of 24% (w/v) saline into the gestation sac in 2 mares by laparotomy. The treatment was successful in one mare (Case 1) and the untreated embryo remained viable. However, neither foetus survived in the second mare (Case 2). Plasma oestrone sulphate (E1S) concentrations fell immediately after treatment in both mares but recovered to approximately 50% of pretreatment levels in Case 1. In Case 2 plasma E1S concentrations declined steadily and were less than 1 ng/ml within 6 days of treatment. These preliminary results suggest that the method may be useful for selective removal of one of twin embryos in mares. Furthermore, plasma E1S concentrations may be a useful indicator of embryonic viability.

Chronic chondritis of the arytenoid cartilages in a pony mare.

The upper respiratory tract of a pony mare with marked exercise intolerance and respiratory stridor was examined with a flexible fibreoptoscope. Both arytenoids were adducted and distorted. A diagnosis of bilateral chondritis of the arytenoids was made and confirmed at autopsy after surgery to enlarge the rima glottidis was unsuccessful. Other space occupying lesions of the rima glottidis are discussed and theories on the aetiology are postulated.