Clinical Research Abstracts of the British Equine Veterinary Association Congress 2015.

REASONS FOR PERFORMING STUDY: New therapeutic strategies to modulate immune responses in human and equine allergic airway diseases are under extensive investigation. Stimulation of Treg cells with immune modulating agents is a novel therapeutic option. OBJECTIVES: The aim of this field study was to compare the effects of a nebulised nanoparticulate CpG immunotherapy (CpG-GNP) with and without specific allergens. STUDY DESIGN: Longitudinal clinical study comparing 2 therapeutic options. METHODS: Twenty RAO-affected horses were divided into 2 treatment groups (CpG alone and CpG with allergens). Two specific allergens were selected for each horse according to anamnesis and a functional in vitro test. Treatments were given by nebulisation 7 times and the horses were examined 3 times: baseline (I), after the treatment course (II), and after 6 weeks later (III). Clinical parameters, indirect intrapleural measurement, arterial blood gas, amount of tracheal mucus and neutrophil percentage were evaluated. RESULTS: CpG alone resulted in a significant improvement in clinical parameters and a significant reduction of tracheal mucus after treatment and at 6 weeks post treatment. After CpG plus specific allergens, there was significant improvement of 70% of examined parameters. However, there were no significant differences in the results compared with CpG-GNP treatment alone. CONCLUSIONS: There were no significant differences between treatment groups. CpG-GNP immunotherapy alone produced a potent and persistent effect on allergic and inflammatory parameters and may have potential as for treatment of equine and human allergic inflammatory airway diseases. Ethical animal research: The study was approved by the regional legal agency for animal experiments of the Government of Bavaria, Germany (No. 55.2-1-54-2531-31-10). Owners gave informed consent for their horses' inclusion in the study. Sources of funding: Partly supported by the Deutsche Forschungsgemeinschaft (DFG) (Germany) (GE'2044/4-1). The AeroNeb Go™ vibrating mesh nebuliser (Aerogen, Galway, Ireland) was sponsored by Inspiration Medical (Bochum, Germany). Competing interests: None declared.

Editor's Choice ­ Durability of Endovascular Repair in Blunt Traumatic Thoracic Aortic Injury: Long-Term Outcome from Four Tertiary Referral Centers.

OBJECTIVES: To analyze the early and long-term survival and re-intervention rate in patients undergoing TEVAR for blunt traumatic thoracic aortic injury. METHODS: This was a consecutive case series. Between the years 2001 and 2010, a total of 74 patients underwent TEVAR for blunt traumatic thoracic aortic injury at four tertiary referral centers, three in Sweden and one in Switzerland. The median age of the patients was 41 years, and 16% were women. Demographic, procedural, and outcome data were collected and reviewed retrospectively. The patients were followed up during 2013-2014. RESULTS: Early (30 day) mortality was 9% (7 patients), with only two cases directly related to the aortic injury; in hospital mortality was 14% as three patients died during the primary hospital admission within the first 6 months. Most patients had sustained severe injuries to other organ systems, and among all in hospital deaths brain injury was the predominant cause. Five year survival in the whole group was 81%. Re-intervention was needed in 16% (12 patients) during the first year, half of them within the first month. Only one patient underwent re-intervention more than 1 year after the initial procedure. Infolding and partial stentgraft collapse was the reason for the secondary procedure in five of the 13 patients; in three it occurred within 3 weeks of the acute TEVAR. CONCLUSION: TEVAR allows rapid and effective therapy in trauma patients with blunt aortic injury. The outcome is dependent on the severity of the concomitant injuries. The treatment is durable during the first decade after the procedure, but even longer follow up is needed to determine the impact of TEVAR in young patients on the degenerative changes that take place in the aging aorta.

Percutaneous closure of large femoral artery access with Prostar XL in thoracic endovascular aortic repair.

OBJECTIVES: To investigate the technical success rate of Prostar XL for closure of large (≥20F) femoral vascular access sites in thoracic endovascular aortic repair (TEVAR) procedures. METHODS: This was a single-center consecutive case series. All TEVAR procedures at Uppsala University Hospital 2006-2010 were registered prospectively. Reoperations and cases with open closure technique were excluded. Primary (early) technical failure was defined as closure failure requiring immediate (on-table) open surgical repair; late access-related complication occurred thereafter. The medical records, pre- and postoperative computed tomography images were reviewed retrospectively. RESULTS: A total of 164 TEVAR procedures were identified, of which 118 (71%) had a median 22F (range 20-26F) access site sealed with tandem Prostar XL. The indications for TEVAR were dissection (47%), aneurysm (42%), trauma (8%), and miscellaneous (3%). Median follow-up time was 10 months (range 1-62). Primary technical failure occurred in 10 of 118 (8%). These cases were converted to cut-downs and surgical repair (n = 7), femoral fascia suturing (n = 2), and external compression with the Femo-Stop device (n = 1). Hypertension was associated with primary failure (p = .005), and a trend was observed for high age (p = .078) and increased groin subcutaneous fat layer (p = .077). Late access-related complications included pseudo-aneurysms (n = 12), small hematomas (n = 7), superficial groin infections (n = 2), and deep venous thrombosis (n = 1). None of the late complications required surgical treatment. CONCLUSIONS: The access closure technique with tandem Prostar XL for large access sites during TEVAR is safe, in experienced hands. Few technical failures and few late complications occur, and they are usually benign.

Plasminogen activator inhibitor-1 levels and activity decrease after intervention in patients with critical limb ischaemia.

OBJECTIVE/BACKGROUND: Patients with peripheral arterial occlusive disease (PAOD), in particular critical limb ischaemia (CLI), carry a high risk of thrombotic events. We hypothesised that patients undergoing conservative, endovascular, or open surgical treatment for CLI have increased levels of plasminogen activator inhibitor-1 (PAI-1), leading to a prothrombotic state. The objective was to determine levels of PAI-1 in patients with acute or chronic PAOD/CLI. METHODS: Thirty-two patients with a median age of 74 (49-90) years were included. Three underwent thrombolysis for acute limb-threatening ischaemia. Twenty-six patients with chronic ischaemia received endovascular (n = 20) or open (n = 6) surgical treatment. Three were treated conservatively. Biomarkers and ankle brachial index (ABI) were measured before and up to 1 month after intervention. Patency was studied with repeated duplex ultrasound. RESULTS: Ankle pressure and ABI improved after intervention (p < .001). C-reactive protein (CRP) increased from a median of 7.90 mg/L at baseline to 31.5 on day 1 (p < .001), 28.0 on day 6 (p < .001), and returned to baseline levels on day 30. PAI-1 antigen and activity decreased from day 6 and onwards post-intervention compared with baseline (p < .05). A great individual variability in PAI-1 antigen and activity was observed. Although most actively treated patients had normal PAI-1 activity, 11/29 (38%) were above that level of normality at baseline, 10/24 (42%) on day 1, 3/23 (13%) on day 6, and 5/27 (19%) on day 30 after intervention. CONCLUSION: Endovascular and open surgical treatment resulted in improved ankle pressure and ABI. The intervention was followed by a transient increase in CRP and a sustained reduction in PAI-1 levels and activity.

Distinction between acute and chronic type B aortic dissection: is there a sub-acute phase?

OBJECTIVES: This study aims to assess the relevance of the definition of acute dissection, to analyse whether there is a sub-acute phase and to determine early outcome of thoracic endovascular aortic repair (TEVAR) in acute complicated type B aortic dissection. DESIGN: Dual-centre consecutive case series. MATERIALS: Between 1999 and 2011, 102 patients underwent TEVAR for non-traumatic acute complicated type B dissection in Zurich, Switzerland, and Uppsala, Sweden. In addition, 22 patients treated for an acute dissection-related complication occurring >14 days after onset of symptoms were included. Median age was 68 years, 35% were women. METHODS: Demographic, procedural and outcome data were collected prospectively. The patients were followed up on 1 January 2012. RESULTS: In the 22 sub-acute patients (18%), there were no early deaths or neurological complications. The predominant complication in these patients was rapid aortic enlargement, whereas rupture was more prevalent in patients treated within 14 days. In total, there were nine (7%) early deaths, three (2%) post-intervention paraplegias and six cases of stroke (5%). CONCLUSIONS: TEVAR was performed with low early mortality and few neurological complications. A significant proportion of patients presented with acute complications >14 days after onset of symptoms, indicative of a sub-acute phase in the transition between acute and chronic dissection, questioning the relevance of the current definition.

Early and long-term outcome after thoracic endovascular aortic repair (TEVAR) for acute complicated type B aortic dissection.

OBJECTIVES: The study aimed to investigate early and long-term outcome of thoracic endovascular aortic repair (TEVAR) for acute complicated type B dissection. DESIGN: This was a retrospective, single-centre, consecutive case series. MATERIALS AND METHODS: During the period 1999-2009, TEVAR was carried out in 50 patients with non-traumatic acute complicated type B dissection, and in another 10 patients with acute complications, including rupture, end-organ ischaemia and acute dilatation during the primary hospitalisation, but >14 days after onset of symptoms. Thus, in total, 60 patients were included; 22 with a DeBakey type IIIa dissection and 38 with a type IIIb; median age was 67 years. Early (30-day) and long-term (5-year) survival, re-intervention rate and complications were recorded until 1 July 2010. RESULTS: Within 30 days, two (3%) deaths, one (2%) paraplegia and three (5%) strokes were observed. Five-year survival was 87% and freedom from re-intervention at 5 years was 65%. CONCLUSIONS: In patients with acute complicated type B aortic dissection, TEVAR can be performed with excellent early and long-term survival, whereas morbidity and long-term durability must be further elucidated.

Increased risk of heart failure as a consequence of perioperative myocardial injury after coronary artery bypass grafting.

OBJECTIVE: To analyse the relation between perioperative myocardial injury (PMI) and the risk of subsequent heart failure after coronary artery bypass grafting (CABG). DESIGN AND SETTING: Clinical data were documented prospectively in all patients and stored in a computer. All hospital readmissions were identified and the registered primary diagnoses were analysed. Survival information on all patients was obtained by use of combined registers. The study was carried out at the cardiac surgical referral centre of University Hospital, Uppsala, Sweden. PATIENTS: 7493 patients discharged alive after primary CABG between 1987 and 1996 were followed up until the first hospital readmission for heart failure, death, or 31 December 1996 was reached. MAIN OUTCOME MEASURES: Hospital readmission for heart failure or late mortality. RESULTS: Of the patients studied 576 (7.7%) were readmitted for heart failure. Actuarial freedom from readmission for heart failure after four years was 93%, and after seven years, 89%. Of the 576 patients, 114 (20%) had had PMI, which increased the risk of heart failure independently (hazard ratio (HR) 2.3, 95% confidence interval (CI) 1.8 to 2.8). Increased age, female sex, diabetes, previous myocardial infarction, dyspnoea, preoperative atrial fibrillation, left ventricular dysfunction, and triple vessel disease were independent risk factors for heart failure. The use of an internal mammary artery decreased the risk. PMI implied increased mortality (HR 1.4, 95% CI 1.1 to 1.8). Late mortality was greatly increased in patients readmitted for heart failure. CONCLUSION: PMI increased the risk of heart failure and late death after CABG, and heart failure had a notable adverse effect on late survival.

Impact of perioperative myocardial injury on early and long-term outcome after coronary artery bypass grafting.

AIMS: To establish the influence of perioperative myocardial injury on short- and long-term survival after coronary artery bypass grafting (CABG). METHODS AND RESULTS: The correlation of postoperative serum aspartate aminotransferase and creatine kinase MB to early cardiac-related death and to late survival was evaluated in 4911 patients who underwent CABG consecutively during a 6-year period. There were 93 early deaths (1.9%), 73 of them cardiac-related (1.5% of 4911). After a mean follow-up of 5 years, 409 additional deaths (8.5% of 4818) had occurred. Elevated enzyme levels on day 1 postoperatively highly increased the risk of early cardiac death (serum aspartate aminotransferase >or=2.35 microkat.l(-1): odds ratio 9.2; serum creatine kinase MB >or=61 microg.l(-1): odds ratio 6.0), and increased the risk of late death by approximately 50% (serum aspartate aminotransferase >or=2.35 microkat.l(-1): relative hazard 1.5; serum creatine kinase MB >or=61 microg.l(-1): relative hazard 1.4). This increased risk of death was independent of other risk factors and remained constant over time. CONCLUSIONS: Enzyme elevation after CABG implied an increased risk of both early and late death. The long-term effect persisted many years after surgery.

Delineating a recharge area for a spring using numerical modeling, Monte Carlo techniques, and geochemical investigation.

Recharge areas of spring systems can be hard to identify, but they can be critically important for protection of a spring resource. A recharge area for a spring complex in southern Wisconsin was delineated using a variety of complementary techniques. A telescopic mesh refinement (TMR) model was constructed from an existing regional-scale ground water flow model. This TMR model was formally optimized using parameter estimation techniques; the optimized "best fit" to measured heads and fluxes was obtained by using a horizontal hydraulic conductivity 200% larger than the original regional model for the upper bedrock aquifer and 80% smaller for the lower bedrock aquifer. The uncertainty in hydraulic conductivity was formally considered using a stochastic Monte Carlo approach. Two-hundred model runs used uniformly distributed, randomly sampled, horizontal hydraulic conductivity values within the range given by the TMR optimized values and the previously constructed regional model. A probability distribution of particles captured by the spring, or a "probabilistic capture zone," was calculated from the realistic Monte Carlo results (136 runs of 200). In addition to portions of the local surface watershed, the capture zone encompassed areas outside of the watershed--demonstrating that the ground watershed and surface watershed do not coincide. Analysis of water collected from the site identified relatively large contrasts in chemistry, even for springs within 15 m of one another. The differences showed a distinct gradation from Ordovician-carbonate-dominated water in western spring vents to Cambrian-sandstone-influenced water in eastern spring vents. The difference in chemistry was attributed to distinctive bedrock geology as demonstrated by overlaying the capture zone derived from numerical modeling over a bedrock geology map for the area. This finding gives additional confidence to the capture zone calculated by modeling.

Methodologic issues associated with secretion weight as a dependent variable in research using closed-system suction catheters.

BACKGROUND: Closed-system suction catheters (CSSC) were designed to eliminate the need to disconnect the patient from the ventilator during endotracheal suctioning (ETS). During data collection on an NIH-funded study, it was noted that moisture accumulated on the inside of the CSSC and sleeve when attached to the patient for 30 minutes. Because CSSC are not disconnected, they present unique methodologic problems related to measurement of secretions as a dependent variable in clinical research. OBJECTIVES: To describe a valid, reliable, and practical method for weighing secretions obtained during ETS using a CSSC; and to determine the change in weight of a CSSC after its attachment for 30 minutes to a mechanically ventilated patient. METHODS: After being weighed, a CSSC and sputum trap were attached to the endotracheal tube of a mechanically ventilated adult and remained attached for 43 minutes (30 minutes to allow positive end expiratory pressure and oxygenation levels to return to normal and 13 minutes to mimic the time frame for the ETS procedure used in another study). No ETS occurred. The CSSC and sputum trap were then removed and reweighed. RESULTS: A convenience sample consisted of 50 adults who were critically ill and mechanically ventilated. Independent variables included tidal volume, pressure support, body temperature, and respiratory rate. The dependent variable was wet weight of the CSSC, determined by subtracting the preprotocol catheter weight from the postprotocol catheter weight. The mean wet weight for all catheters was 0.5142 +/- 0.1215 grams. In a subset of 37 patients, two wet weights (74 paired observations) were determined. The mean wet weight for these catheters was 0.54014 +/- 0.1404 grams. The paired wet weights were statistically different (t = 2.433; df = 36; p = 0.02). Pearson correlation coefficients and beta coefficients were computed. While tidal volume and pressure support were highly correlated (r = 0.678; p = 0.011), there were no other statistically significant associations. CONCLUSIONS: The amount of secretions is a common dependent variable in ETS research. During the time that CSSC are attached to the patient and ventilator, moisture from either the ventilator's humidification system or the patient accumulates in the CSSC. This wet weight is not actually part of the secretions retrieved during ETS and should not be considered in the actual weight of secretions. Further study on the determinants of wet weight is warranted.

[Neurological complications after open heart surgery. Risk factors identified in a retrospective study]. / Neurologiska komplikationer efter öppen hjärtkirurgi. Riskfaktorer identifierade i retrospektiv studie.

Cerebral complications were documented in 2 per cent (133/6666) of open heart procedures performed in adults at the Karolinska hospital, during the 7-year period, 1990-96. In 32 per cent (42/133) of cases, the neurological symptoms appeared after an uneventful postoperative interval of 2-14 (median 3) days. These patients were older and were characterised by a tendency toward a greater prevalence of carotid artery disease and of postoperative atrial arrhythmia. By contrast, the subgroup whose cerebral symptoms occurred immediately after the operation was characterised by greater severity of the symptoms, long operation time, and poor preoperative left ventricular function. Aggressive postoperative anticoagulant treatment, especially in patients with supraventricular arrhythmias, would seem to be justified to reduce the risk of neurological complications.

The use of combination internal fixation and hybrid external fixation in severe proximal tibia fractures.

Forty-eight patients with 50 severe fractures of the proximal tibia were followed prospectively for 2-4 years (mean 2.7 years) to evaluate the use of limited internal fixation combined with external fixation in the treatment of these injuries. There were 27 men and 21 women ranging in age from 20 to 74 years. Fractures were classified according to the A0 system (Mast J, Ganz R, Jacob R: Planning and reduction technique in fracture surgery. Berlin, Springer-Verlag, 1989), which included 5 A3, 6 C1, 16 C2, and 23 C3 fractures. All patients in this series healed; 48 fractures healed in an average of 12 weeks without subsequent surgery. There were two (4%) nonunions requiring bone graft. The average hospital special surgery knee score was 90 (68-100). Grading criteria for anatomical outcome revealed there were 17 (34%) excellent results, 24 (48%) good results, 6 (12%) fair results, and 3 (6%) poor results. In conclusion, this treatment method is associated with a high percentage of good and excellent results. Combined internal and external fixation combines the advantages of anatomic, stable fixation with less soft-tissue dissection and eliminates the need for large implants.

Treatment of grade-IIIb open tibial fractures. A prospective randomised comparison of external fixation and non-reamed locked nailing.

Severe open fractures of the tibia have a high incidence of complications and a poor outcome. The most usual method of stabilisation is by external fixation, but the advent of small diameter locking intramedullary nails has introduced a new option. We report the early results of a randomised, prospective study comparing external fixation with non-reamed locked nails in grade-IIIb open tibial fractures. Of 29 patients, 15 were treated by nails and 14 by external fixation. Both groups had the same initial management, soft-tissue procedures, and early bone grafting. All 29 fractures healed within nine months, but the nailed group had slightly better motion and less final angulation. Complications included one deep infection and two pin-track infections in the external fixator group and one deep infection and one vascular problem in the nailed group. Although the differences in healing and range of motion were not statistically significant, we found that the nailed fractures were consistently easier to manage, especially in terms of soft-tissue procedures and bone grafting. It is the treatment preferred by patients and does not require the same high level of patient compliance as external fixation. The only factors against nailing are the longer operating time and the greater need for fluoroscopy. We consider that locked non-reamed nailing is the treatment of choice for grade-IIIb open tibial fractures.

Pilon fractures: treatment with combined internal and external fixation.

The purpose of this study was to prospectively evaluate the use of limited internal fixation and the application of a hybrid external fixator (tensioned wires distally and 5.0 mm half pins proximally attached to a semicircular frame without crossing the ankle joint) in the treatment of severe distal tibia fractures. This technique involves accurate reduction and fixation of the intraarticular component through an incision based over a fracture site followed by stabilization of the metaphysis with the hybrid external fixator. We studied 26 patients 15-55 years of age who were followed for 8-36 months. All fractures were within 5 cm of the joint. Seventeen fractures were intraarticular, nine extraarticular, and six open. Eleven patients required bone grafting. The average time to healing was 4.2 months. Using clinically based criteria, there were 81% good and excellent results overall, 70.5% for the 17 intraarticular fractures, and 69% for Ruedi type III fractures. Complications included one superficial and one deep infection, one 10 degrees varus malunion, and three pin tract infections. This method yielded results comparable with previous studies while reducing the amount of soft tissue dissection necessary for the placement of large plates. Soft tissue complications were infrequent and the goals of early motion and fracture stability were not sacrificed.

[Basic and advanced training in radiation protection in stomatology]. / Aus- und Weiterbildung im Strahlenschutz in der Stomatologie.

Considering the importance of radiation protection in dental radiology and the respective legal regulations of the GDR, objectives and contents of basic and advanced training of responsible co-workers in radiation protection are described. Particular organisational aspects regarding training courses in the National Board for Atomic Safety and Radiation Protection are outlined.