Damage-control vascular surgery in Canada: supporting surgeons and teams.

SummaryIn Canada, trauma patients often present initially to non-trauma hospitals without vascular surgeons on site. Local surgeons need skills and support for damage-control vascular surgery. Canadian training programs in general surgery should equip trainees with skills in this area, including resuscitation, identification of vascular injury, hemorrhage control, and temporizing measures (e.g., shunts, ligation). Caring for trauma patients is a multidisciplinary endeavour; understanding local/regional skill sets and from whom to seek help is vital. Opportunities for skills maintenance should also be encouraged for surgeons practising at sites where acutely injured patients present.

Cardiopulmonary resuscitation outcomes of dogs and cats at a veterinary teaching hospital before and after publication of the RECOVER guidelines.

OBJECTIVES: To describe and compare cardiopulmonary resuscitation outcomes at a Swiss veterinary teaching hospital before and after publication of the Reassessment Campaign on Veterinary Resuscitation guidelines. MATERIALS AND METHODS: Between 2018 and 2020, hospital staff underwent various types of yearly Reassessment Campaign on Veterinary Resuscitation-based cardiopulmonary resuscitation trainings. Canine and feline cardiopulmonary resuscitation events during that period (post-Reassessment Campaign on Veterinary Resuscitation) and between 2010 and 2012 (pre-Reassessment Campaign on Veterinary Resuscitation) were identified and animal, arrest and outcome variables recorded retrospectively. RESULTS: Eighty-one animals were included in the pre-Reassessment Campaign on Veterinary Resuscitation group and 190 in the post-Reassessment Campaign on Veterinary Resuscitation group. Twenty-three percent in the pre-Reassessment Campaign on Veterinary Resuscitation group and 28% in the post-Reassessment Campaign on Veterinary Resuscitation group achieved return of spontaneous circulation and 1% and 4% survived to hospital discharge, respectively. Patients undergoing anaesthesia [odds ratio 4.26 (1.76 to 10.27)], elective [odds ratio 5.16 (1.06 to 25.02)] or emergent surgery [odds ratio 3.09 (1.20 to 8.00)], or experiencing cardiopulmonary arrest (CPA) due to arrhythmias [odds ratio 4.31 (1.44 to 12.93)] had higher odds of return of spontaneous circulation, while those with unknown cause of CPA [odds ratio 0.25 (0.08 to 0.78)] had lower odds. Undergoing cardiopulmonary resuscitation in the post-Reassessment Campaign on Veterinary Resuscitation period was not statistically significantly associated with return of spontaneous circulation [odds ratio 1.38 (0.68 to 2.79)]. CLINICAL SIGNIFICANCE: Unchanged odds of return of spontaneous circulation observed in this study could suggest that once-yearly cardiopulmonary resuscitation training is insufficient, effects of animal and tertiary referral hospital variables confounded results, guideline benefit is limited, or that compliance during clinical cardiopulmonary resuscitation efforts is too poor for guideline recommendations to have a positive impact.

Plasma-Enhanced Atomic Layer Deposition of Nickel Nanotubes with Low Resistivity and Coherent Magnetization Dynamics for 3D Spintronics.

We report plasma-enhanced atomic layer deposition (ALD) to prepare conformal nickel thin films and nanotubes using nickelocene as a precursor, water as the oxidant agent, and an in-cycle plasma-enhanced reduction step with hydrogen. The optimized ALD pulse sequence, combined with a post-processing annealing treatment, allowed us to prepare 30 nm-thick metallic Ni layers with a resistivity of 8 µΩ cm at room temperature and good conformality both on the planar substrates and nanotemplates. Thus, we fabricated several micrometers-long nickel nanotubes with diameters ranging from 120 to 330 nm. We report the correlation between ALD growth and functional properties of individual Ni nanotubes characterized in terms of magnetotransport and the confinement of spin-wave modes. The findings offer novel perspectives for Ni-based spintronics and magnonic devices operated in the GHz frequency regime with 3D device architectures.

Effect of atmospheric carbon dioxide concentration on the cultivation of bovine Mycoplasma species.

Recommendations for bovine mycoplasma culture CO2 concentrations are varied and were not empirically derived. The objective of this study was to determine whether the growth measures of bovine mycoplasma isolates differed when incubated in CO2 concentrations of 10 or 5% or in candle jars (2.7 ± 0.2% CO2). Growth of Mycoplasma bovis (n = 22), Mycoplasma californicum (n = 18), and other Mycoplasma spp. (n = 10) laboratory isolates was evaluated. Isolate suspensions were standardized to approximately 108 cfu/mL and serially diluted in pasteurized whole milk to achieve test suspensions of 102 and 106 cfu/mL. One hundred microliters of each test dilution was spread in duplicate onto the surface of a modified Hayflick's agar plate. Colony growth was enumerated on d 3, 5, and 7 of incubation. A mixed linear model included the fixed effects of CO2 treatment (2.7, 5, or 10%), species, day (3, 5, or 7), and their interactions, with total colony counts as the dependent variable. Carbon dioxide concentration did not significantly affect overall mycoplasma growth differences, but differences between species and day were present. Colony counts (log10 cfu/mL) of M. bovis were 2.6- and 1.6-fold greater than M. californicum and other Mycoplasma spp., respectively. Growth at 7 d of incubation was greater than d 3 and 5 for all species. These findings were confirmed using field isolates (n = 98) from a commercial veterinary diagnostic laboratory. Binary growth responses (yes/no) of the field isolates were not different between CO2 treatments but did differ between species and day of incubation. On average, 57% of all field isolates were detected by 3 d of incubation compared with 93% on d 7. These results suggest that the range of suitable CO2 culture conditions and incubation times for the common mastitis-causing Mycoplasma spp. may be broader than currently recommended.

Pharmacodynamics and proteomic analysis of acalabrutinib therapy: similarity of on-target effects to ibrutinib and rationale for combination therapy.

Acalabrutinib, a highly selective Bruton's tyrosine kinase inhibitor, is associated with high overall response rates and durable remission in previously treated chronic lymphocytic leukemia (CLL); however, complete remissions were limited. To elucidate on-target and pharmacodynamic effects of acalabrutinib, we evaluated several laboratory endpoints, including proteomic changes, chemokine modulation and impact on cell migration. Pharmacological profiling of samples from acalabrutinib-treated CLL patients was used to identify strategies for achieving deeper responses, and to identify additive/synergistic combination regimens. Peripheral blood samples from 21 patients with relapsed/refractory CLL in acalabrutinib phase I (100-400 mg/day) and II (100 mg BID) clinical trials were collected prior to and on days 8 and 28 after treatment initiation and evaluated for plasma chemokines, reverse phase protein array, immunoblotting and pseudoemperipolesis. The on-target pharmacodynamic profile of acalabrutinib in CLL lymphocytes was comparable to ibrutinib in measures of acalabrutinib-mediated changes in CCL3/CCL4 chemokine production, migration assays and changes in B-cell receptor signaling pathway proteins and other downstream survival proteins. Among several CLL-targeted agents, venetoclax, when combined with acalabrutinib, showed optimal complementary activity in vitro, ex vivo and in vivo in TCL-1 adoptive transfer mouse model system of CLL. These findings support selective targeting and combinatorial potential of acalabrutinib.

Positive Trend in the Antarctic Sea Ice Cover and Associated Changes in Surface Temperature.

The Antarctic sea ice extent has been slowly increasing contrary to expected trends due to global warming and results from coupled climate models. After a record high extent in 2012 the extent was even higher in 2014 when the magnitude exceeded 20×106 km2 for the first time during the satellite era. The positive trend is confirmed with a newly reprocessed sea ice data that addressed inconsistency issues in the time series. The variability in sea ice extent and ice area was studied alongside surface ice temperature for the 34-year period starting 1981 and the result of the analysis show a strong correlation of -0.94 during the growth season and -0.86 during the melt season. The correlation coefficients are even stronger with a one-month lag in surface temperature at -0.96 during the growth season and -0.98 during the melt season suggesting that the trend in sea ice cover is strongly influenced by the trend in surface temperature. The correlation with atmospheric circulation as represented by the Southern Annular Mode (SAM) index appears to be relatively weak. A case study comparing the record high in 2014 with a relatively low ice extent in 2015 also shows strong sensitivity to changes in surface temperature. The results suggest that the positive trend is a consequence of the spatial variability of global trends in surface temperature and that the ability of current climate models to forecast sea ice trend can be improved through better performance in reproducing observed surface temperatures in the Antarctic region.

Prognostic value of pretreatment circulating neutrophils, monocytes, and lymphocytes on outcomes in lung stereotactic body radiotherapy.

PURPOSE: In the present study, we determined the association of pretreatment circulating neutrophils, monocytes, and lymphocytes with clinical outcomes after lung stereotactic body radiotherapy (sbrt). METHODS: All patients with primary lung cancer and with a complete blood count within 3 months of lung sbrt from 2005 to 2012 were included. Overall survival (os) was calculated using the Kaplan-Meier method. Factors associated with os were investigated using univariable and multivariable Cox proportional hazards regression. Fine-Gray competing risk regression was performed to test the association of the neutrophil:lymphocyte (nlr) and monocyte:lymphocyte (mlr) ratios with two types of failure: disease-related failure and death, and death unrelated to disease. RESULTS: Of the 299 sbrt patients identified, 122 were eligible for analysis. The median and range of the nlr and mlr were 3.0 (0.3-22.0) and 0.4 (0.1-1.9) respectively. On multivariable analysis, sex (p = 0.02), T stage (p = 0.04), and nlr (p < 0.01) were associated with os. On multivariable analysis, T stage (p < 0.01) and mlr (p < 0.01) were associated with disease-related failure; mlr (p = 0.03), nlr (p < 0.01), and sbrt dose of 48 Gy in 4 fractions (p = 0.03) and 54 Gy or 60 Gy in 3 fractions (p = 0.02) were associated with disease-unrelated death. Median survival was 4.3 years in the nlr≤3 group (95% confidence interval: 3.5 to not reached) and 2.5 years in the nlr>3 group (95% confidence interval: 1.7 to 4.8; p < 0.01). CONCLUSIONS: In lung sbrt patients, nlr and mlr are independently associated with os and disease-unrelated death. If validated, nlr and mlr could help to identify patients who would benefit most from sbrt.

A Ten year review of alcohol use and major trauma in a Canadian province: still a major problem.

BACKGROUND: Alcohol plays a significant role in major traumatic injuries. While the role of alcohol in motor vehicle trauma (MVT) is well described, its role and approaches to prevention in other injury mechanisms is less defined. METHODS: A 10 year retrospective examination of Alberta Trauma Registry (ATR) data was conducted on all major trauma patients (age ≥ 9 and ISS ≥ 12) from 2001-2010. The role and prevalence of alcohol is examined. RESULTS: Of 22,457 patients included in our study, only 60 %(n = 13,552) were screened for alcohol use. Of those screened, 38 %(n = 5,170) tested positive for alcohol with a mean blood alcohol concentration (BAC) of 39.4 ± 21.1 mmol/L. Of the positive screening tests, 82.3 % had BAC levels greater than the common legal driving limit of 17.4 mmol/L (0.08 %). Testing positive was associated with male gender (p < 0.001) and younger age (p < 0.001). The rate of positive alcohol use in major trauma increased from 20.3 % in 2001 to 24.3 % in 2010, corresponding with a screening rate increase from 51.3 % to 61.2 % over the same period. Railway incidents have the highest rate of alcohol involvement (65 %), followed by undetermined-if-accidental/self-inflicted (53.5 %) and assault (49 %); motor vehicle traffic (MVT) incidents had a frequency of 25.4 %. CONCLUSIONS: The prevalence of alcohol use in major trauma appears to be increasing in Alberta but the true extent is still underappreciated. Furthermore, the role of alcohol in non-MVT injuries is significant and deserves further attention. The vast majority of patients involved in alcohol-related trauma are legally intoxicated. Alcohol use continues to be a substantial contributor to major trauma in Alberta, and represents an important opportunity to reduce preventable injuries.

Reduction of teat skin mastitis pathogen loads: differences between strains, dips, and contact times.

The purpose of these experiments was to (1) assess differences in mastitis pathogen strain sensitivities to teat disinfectants (teat dips), and (2) determine the optimum time for premilking teat dips to remain in contact with teat skin to reduce pathogen loads on teat skin. Two experiments were conducted using the excised teat model. In experiment 1, the differences in mastitis pathogen strain sensitivities to 4 commercially available dips (dip A: 1% H2O2; dip B: 1% chlorine dioxide; dip C: 1% iodophor; and dip D: 0.5% iodophor) were evaluated. Four strains of 11 common mastitis pathogens (Staphylococcus aureus, Streptococcus agalactiae, Mycoplasma bovis, Streptococcus dysgalactiae, Streptococcus uberis, Escherichia coli, Staphylococcus chromogenes, Staphylococcus epidermidis, Staphylococcus hyicus, Staphylococcus xylosus, and Staphylococcus haemolyticus) were tested. In experiment 2, the percentage log reduction of mastitis pathogens (Escherichia coli, Streptococcus uberis, Streptococcus dysgalactiae, Klebsiella species, Staphylococcus chromogenes, Staphylococcus haemolyticus, Staphylococcus xylosus, and Staphylococcus epidermidis) on teat skin with 3 commercially available teat dips: dip A; dip D; and dip E: 0.25% iodophor, using dip contact times of 15, 30, and 45 s, was evaluated. Experiment 1 results indicated significant differences in strain sensitivities to dips within pathogen species: Staphylococcus aureus, Staphylococcus chromogenes, and Streptococcus uberis. Species differences were also found where Mycoplasma bovis (97.9% log reduction) was the most sensitive to tested teat dips and Staphylococcus haemolyticus (71.4% log reduction) the most resistant. Experiment 2 results indicated that contact times of 30 and 45 s were equally effective in reducing recovered bacteria for dips D and E and were also significantly more effective than a 15-s contact time. No differences were seen in recovered bacteria between tested contact times after treatment with dip A. It can be concluded that different mastitis pathogen species and strains within species may possess different sensitivities to teat dips, which may have implications in selection of teat dips on dairies. Furthermore, a 30-s premilking dip contact time for iodophors and 15 s for H2O2 dips may be optimal in reducing pathogen load in the shortest amount of time. A reduction in premilking teat dip contact time may improve milking parlor efficiency.

Calm temperament improves reproductive performance of beef cows.

Profitability of a beef operation is determined by the proportion of cows attaining pregnancy early in the breeding season and those that are pregnant at the end of breeding season. Many factors, including temperament, contribute to those reproductive parameters. The objective of this study was to evaluate effects of temperament on reproductive performance of beef cows. In Experiment 1, Angus and Angus-cross beef cows (n = 1546) from eight locations were assigned a body condition score (BCS; 1 = emaciated; 9 = obese) and chute exit and gait score (1 = slow exit, walk; calm temperament; 2 = jump, trot or run; excitable temperament). Cows were grouped with bulls (1 : 25 to 1 : 30; with satisfactory breeding potential and free of venereal disease) for an 85-day breeding season. Pregnancy status and stage of gestation were determined (transrectal palpation) 35 days after the end of the breeding season. Controlling for BCS (p < 0.01) and handling facility (p < 0.0001) and handling facility by temperament score interaction (p < 0.001), breeding season pregnancy rate was lower in excited versus calm cows [88.6% (798/901) vs 94.1% (607/645); p < 0.001]. Cows with an excitable temperament took 24 more days to become pregnant compared to calm cows (median days to pregnancy, 35 vs 59 days; p < 0.0001). In Experiment 2, Angus and Angus-cross beef cows (n = 1407) from 8 locations were assigned scores for body condition and chute exit and gait (as described in Experiment 1) and assigned to bulls (breeding sound and free of venereal disease; 1 : 25 to 1 : 30) for 85 days. Pregnancy status was determined by transrectal palpation at 2 and 6 months after the onset of the breeding season. Controlling for BCS (p < 0.05), pregnancy loss was higher in excited versus calm cows [5.5% (36/651) vs 3.2% (20/623), p < 0.0001]. In conclusion, beef cows with an excitable temperament had significantly lower reproductive performance than calmer cows. The modified two-point chute exit-gait scoring method was repeatable and identified cattle with an excitable temperament.

Influence of temperament score and handling facility on stress, reproductive hormone concentrations, and fixed time AI pregnancy rates in beef heifers.

The objectives were (i) to evaluate the effect of temperament, determined by modified 2-point chute exit and gait score, on artificial insemination (AI) pregnancy rates in beef heifers following fixed time AI and (ii) to determine the effect of temperament on cortisol, substance-P, prolactin and progesterone at initiation of synchronization and at the time of AI. Angus beef heifers (n = 967) at eight locations were included in this study. At the initiation of synchronization (Day 0 = initiation of synchronization), all heifers received a body condition score (BCS), and temperament score (0 = calm; slow exit and walk or 1 = excitable; fast exit or jump or trot or run). Blood samples were collected from a sub-population of heifers (n = 86) at both synchronization initiation and the time of AI to determine the differences in serum progesterone, cortisol, prolactin and substance-P concentrations between temperament groups. Heifers were synchronized with 5-day CO-Synch+ controlled internal drug release (CIDR) protocol and were inseminated at 56 h after CIDR removal. Heifers were examined for pregnancy by ultrasound 70 days after AI to determine AI pregnancy. Controlling for synchronization treatment (p = 0.03), facility design (p = 0.05), and cattle handling facility design by temperament score interaction (p = 0.02), the AI pregnancy differed between heifers with excitable and calm temperament (51.9% vs 60.3%; p = 0.01). The alley-way with acute bends and turns, and long straight alley-way had lower AI pregnancy rate than did the semicircular alley-way (53.5%, 56.3% and 67.0% respectively; p = 0.05). The serum hormone concentrations differed significantly between different types of cattle handling facility (p < 0.05). The cattle handling facility design by temperament group interactions significantly influenced progesterone (p = 0.01), cortisol (p = 0.01), prolactin (p = 0.02) and substance-P (p = 0.04) both at the initiation of synchronization and at the time of AI. Inter- and intra-rater agreement for temperament scoring were moderate and good (Kappa = 0.596 ± 0.07 and 0.797 ± 0.11) respectively. The predictive value for calm and pregnant to AI was 0.87, and excited and non-pregnant to AI was 0.76. In conclusion, the modified 2-point temperament scoring method can be used to identify heifers with excitable temperament. Heifers with excitable temperament had lower AI pregnancy. Further, cattle handling facility design influenced the temperament and AI pregnancy.

Effect of reproductive tract scoring on reproductive efficiency in beef heifers bred by timed insemination and natural service versus only natural service.

The objective was to determine the effects of reproductive tract score (RTS) on reproductive performance in beef heifers bred by timed artificial insemination followed by natural service (AI-NS) or by natural service only (NSO). Angus cross beef heifers (n = 2660) in the AI-NS group were artificially inseminated at a fixed time (5- or 7-day CO-Synch + controlled internal drug release protocol) once, then exposed to bulls 2 weeks later (bull-to-heifer ratio = 1:40-1:50) for the reminder of the 85-day breeding season. Angus cross beef heifers (n = 1381) in NSO group were submitted to bulls (bull-to-heifer ratio = 1:20-1:25) for the entire 85-day breeding season. Heifers were reproductive tract scored from 1 (prepubertal) to 5 (cyclic) 4 weeks before, and were body condition scored (BCS) from 1 (emaciated) to 9 (obese) at the beginning of breeding season. Pregnancy diagnosis was performed 70 days after AI for AI-NS group and 2 months after the end of breeding season for both groups. Heifers in both groups were well managed and of similar age (14.9 ± 0.4 [AI-NS] and 14.7 ± 0.8 [NSO] months). Pregnancy rates (PRs) and number of days to become pregnant were calculated using PROC GLIMMIX and PROC LIFETEST procedures of SAS. Adjusting for BCS (P = 0.07), expressed estrus (P < 0.05), year (P < 0.05), and BCS by year interaction (P < 0.05), the AI-PR was greater for heifers in AI-NS group with higher RTS (P < 0.0001; 40.7%, 48.3%, 57.6%, and 64.6% for RTS of 2 or less, 3, 4, and 5, respectively). Controlling for BCS (P < 0.05), year (P < 0.05) and the breeding season pregnancy rates (BS-PRs) were greater for heifers in the AI-NS group with higher RTS (P < 0.01; 81.2%, 86.5%, 90.4%, and 95.2% for RTS of 2 or less, 3, 4, and 5, respectively). Similarly, adjusting for BCS, year (P < 0.05), the BS-PR was greater for heifers in NSO group with higher RTS (P < 0.01; 79.7%, 84.3%, 88.4%, and 90.2% for RTS of 2 or less, 3, 4, and 5, respectively). Heifers with higher RTS in both groups became pregnant earlier in the breeding season compared with heifers with lower RTS (log-rank statistics: P < 0.0001). Heifers in the AI-NS group become pregnant at a faster rate compared with those in the NSO group (P < 0.01). The BS-PR for heifers with RTS 5 was different between AI-NS and NSO groups (P < 0.0001). In conclusion, the RTS influenced both the number of beef heifers that became pregnant during the breeding season and the time at which they become pregnant. Furthermore, irrespective of RTS, heifers bred by NSO required more time to become pregnant than their counterparts in herds that used timed AI. The application of RTS system is reliant on the use of synchronization protocol. The application of RTS for selection may plausibly remove precocious females with lower RTS. On the contrary, application of RTS would help select heifers that will become pregnant earlier in breeding season.

Effect of the first GnRH and two doses of PGF2α in a 5-day progesterone-based CO-Synch protocol on heifer pregnancy.

The objectives were (1) to determine the effects of gonadorelin hydrochloride (GnRH) injection at controlled internal drug release (CIDR) insertion on Day 0 and the number of PGF2α doses at CIDR removal on Day 5 in a 5-day CO-Synch + CIDR program on pregnancy rate (PR) to artificial insemination (AI) in heifers; (2) to examine how the effect of systemic concentration of progesterone and size of follicles influenced treatment outcome. Angus cross beef heifers (n = 1018) at eight locations and Holstein dairy heifers (n = 1137) at 15 locations were included in this study. On Day 0, heifers were body condition scored (BCS), and received a CIDR. Within farms, heifers were randomly divided into two groups: at the time of CIDR insertion, the GnRH group received 100 µg of GnRH and No-GnRH group received none. On Day 5, all heifers received 25 mg of PGF2α at the time of CIDR insert removal. The GnRH and No-GnRH groups were further divided into 1PGF and 2PGF groups. The heifers in 2PGF group received a second dose of PGF2α 6 hours after the administration of the first dose. Beef heifers underwent AI at 56 hours and dairy heifers at 72 hours after CIDR removal and received 100 µg of GnRH at the time of AI. Pregnancy was determined approximately at 35 and/or 70 days after AI. Controlling for herd effect (P < 0.06), the treatments had significant effect on AI pregnancy in beef heifers (P = 0.03). The AI-PRs were 50.3%, 50.2%, 59.7%, and 58.3% for No-GnRH + PGF + GnRH, No-GnRH + 2PGF + GnRH, GnRH + PGF + GnRH, and GnRH + 2PGF + GnRH groups, respectively. The AI-PRs were ranged from 50% to 62.4% between herds. Controlling for herd effects (P < 0.01) and for BCS (P < 0.05), the AI pregnancy was not different among the treatment groups in dairy heifers (P > 0.05). The AI-PRs were 51.2%, 51.9%, 53.9%, and 54.5% for No-GnRH + PGF + GnRH, No-GnRH + 2PGF + GnRH, GnRH + PGF + GnRH, and GnRH + 2PGF + GnRH groups, respectively. The AI-PR varied among locations from 48.3% to 75.0%. The AI-PR was 43.5%, 50.4%, and 64.2% for 2.5 or less, 2.75 to 3.5, and greater than 3.5 BCS categories. Numerically higher AI-PRs were observed in beef and dairy heifers that exhibited high progesterone concentrations at the time of CIDR insertion (>1 ng/mL, with a CL). In addition, numerically higher AI-PRs were also observed in heifers receiving CIDR + GnRH with both high and low progesterone concentration (<1 ng/mL) initially compared with heifers receiving a CIDR only with low progesterone. In dairy heifers, there were no differences in the pregnancy loss between 35 and 70 days post-AI among the treatment groups (P > 0.1). In conclusion, GnRH administration at the time of CIDR insertion is advantageous in beef heifers, but not in dairy heifers, to improve AI-PR in the 5-day CIDR + CO-Synch protocol. In addition, in this study, both dairy heifers that received either one or two PGF2α doses at CIDR removal resulted in similar AI-PR in this study regardless of whether they received GnRH at CIDR insertion.

Biomechanical strength of two laparoscopic herniorrhaphy techniques in a cadaveric diaphragm and in a neoprene model.

OBJECTIVES: Our objectives were to 1) Biomechanically compare two laparoscopic repair techniques; an automated suturing device and a stapling device to conventional open suturing, and 2) Evaluate a model for canine diaphragmatic tissue by comparisons to similar constructs in fresh diaphragms. We hypothesized that automated suturing is biomechanically superior to laparoscopic stapling in dogs, and that neoprene defect repair is an acceptable model for experimental cadaveric diaphragm herniorrhaphy. MATERIALS AND METHODS: Samples of diaphragm pars costalis were prepared with defects mimicking radial muscular tears. Defects were repaired using conventional open suturing, laparoscopic automated suturing, and laparoscopic stapling techniques. Similar defects were created in 6.35 mm thick single-sided neoprene. Samples were biomechanically tested across a biaxial loading machine. Site and mode of failure were noted for all samples. RESULTS: In both the diaphragm muscle and neoprene, the laparoscopic stapling technique was significantly weaker. The neoprene model showed a similar failure load as the diaphragm in both laparoscopic techniques, and a similar stiffness in an open-sutured and stapled diaphragm compared to the neoprene samples. Site and mode of failure in neoprene were similar to cadaveric diaphragmatic tissue, but the overall median load-to-failure was higher for the neoprene. CONCLUSION: The strength of laparoscopically repaired simulated diaphragmatic hernias was higher with an automated suture technique than with a stapling technique. Neoprene defect repair is an acceptable model of canine diaphragmatic herniorrhaphy for biomechanical testing.