Comparison of manual compression, Z-stitch, and suture-mediated vascular closure device techniques in dogs undergoing percutaneous transvenous intervention.

INTRODUCTION/OBJECTIVES: Manual compression has been standard of care for maintaining hemostasis after percutaneous endovascular intervention, but can be time-consuming and associated with vascular complications. Alternative closure methods include the figure-of-eight suture (Z-stitch) and vascular closure device (VCD) techniques. We hypothesized that compared to manual compression, Z-stitch and VCD would significantly reduce time-to-hemostasis after transvenous access, and the proportion of dogs with vascular patency would not differ significantly among treatments. ANIMALS: Forty-six client-owned dogs undergoing percutaneous transvenous interventional procedures. MATERIALS AND METHODS: Dogs with vessel diameter <5 mm were randomized to undergo manual compression or Z-stitch, while those with vessel diameter ≥5 mm were randomized to undergo manual compression, Z-stitch, or VCD. Time-to-hemostasis, bleeding scores, presence of vascular patency one day and two to three months post-procedure, and complications were recorded. Data are presented as median (95% confidence interval). RESULTS: In all 46 dogs, the right external jugular vein was used. Time-to-hemostasis was significantly shorter in the Z-stitch (2.1 [1.8-2.9] minutes) compared to VCD (8.6 [6.1-11.8] minutes; P<0.001) and manual compression (10.0 [10.0-20.0] minutes; P<0.001) groups. Time-to-hemostasis was significantly shorter in the VCD vs. manual compression (P=0.027) group. Bleeding scores were significantly greater at 5 and 10 min (P<0.001 and 0.013, respectively) in manual compression, compared to Z-stitch group. There was no difference in the proportion of dogs with vascular patency between groups (P=0.59). CONCLUSIONS: Z-stitch and VCD are effective venous hemostasis methods after percutaneous transvenous intervention, with Z-stitch providing the most rapid time-to-hemostasis. Both Z-stitch and VCD techniques have low complication rates and effectively maintain vascular patency.

Temporary abdominal packing for management of persistent hemorrhage after liver lobectomy in three dogs with hepatic neoplasia.

OBJECTIVE: To describe the technique and outcome of temporary abdominal packing for control of persistent hemorrhage from liver lobectomy sites in 3 dogs with hepatic neoplasia. SERIES SUMMARY: Three dogs were treated with massive transfusion for hemoperitoneum secondary to bleeding hepatic tumors. Surgical resection of the affected liver lobe(s) was performed but hemostasis could not be achieved through conventional methods. All 3 dogs demonstrated acidosis, hypothermia, and coagulopathy. Temporary abdominal packing of liver lobectomy sites was performed and hemostasis was achieved in all dogs. One dog died prior to removal of the packing. The other 2 dogs had the packing removed with no evidence of rebleeding. One dog was euthanized after removal of the packing due to acute kidney injury and the remaining dog survived to discharge. NEW OR UNIQUE INFORMATION PROVIDED: Temporary abdominal packing combined with medical management was successful in achieving hemostasis in all 3 dogs, however, 2 dogs died of complications related to multiple organ dysfunction syndrome. Temporary abdominal packing may be considered when definitive surgical hemostasis cannot be achieved or in unstable patients not able to tolerate prolonged surgical times. Further research is needed to better define efficacy, optimal patient selection, packing technique, timing of removal, and complications associated with temporary abdominal packing.

Use of a vessel-sealing device versus conventional hemostatic techniques in dogs undergoing thyroidectomy because of suspected thyroid carcinoma.

OBJECTIVE: To compare use of a vessel-sealing device (VSD) versus conventional hemostatic techniques in dogs undergoing thyroidectomy because of suspected thyroid carcinoma. DESIGN: Retrospective cohort study. ANIMALS: 42 client-owned dogs undergoing thyroidectomy because of suspected thyroid carcinoma. PROCEDURES: Medical records of dogs treated at 4 referral centers from 2010 through 2016 were reviewed, and information was obtained on patient signalment, surgical technique, tumor-specific factors, and operative duration. Postoperative hospitalization time and complications were compared between dogs grouped on the basis of hemostatic technique. RESULTS: Thyroidectomy was performed with a VSD in 23 dogs and with conventional hemostatic techniques (ie, ligatures, hemoclips, or electrocautery) in 19 dogs. Hemostatic technique (ie, use of a VSD vs conventional hemostatic techniques) was the only factor significantly associated with operative duration (median time, 28 vs 41 minutes). Postoperative hospitalization times and complication rates did not differ between groups. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that use of a VSD, rather than conventional hemostatic techniques, in dogs undergoing thyroidectomy because of suspected thyroid carcinoma resulted in shorter operative times without significantly affecting complication rates or postoperative hospitalization times.

Use of a vascular closure device during percutaneous arterial access in a dog with impaired hemostasis.

OBJECTIVE: To report the use of a vascular closure device (VCD) to provide rapid arterial hemostasis following percutaneous femoral arterial catheterization and diagnostic angiography in a thrombocytopenic and coagulopathic dog. CASE SUMMARY: A 6-year-old female spayed Kai Ken Tora dog presented after vehicular trauma. The dog was diagnosed with traumatic pneumothorax, degloving wounds of the right antebrachium, subcutaneous hemorrhage within the axillary tissues of the left thoracic limb, and anemia and thrombocytopenia secondary to acute hemorrhage. Treatment included therapeutic thoracocentesis and open wound management of the right thoracic limb as well as packed RBC and fresh frozen plasma transfusions. Diagnostic angiography of the left brachial artery was performed via percutaneous femoral arterial access to investigate the source of a persistent axillary hematoma. The arterial access site was closed using an extraluminal VCD and hemostasis was immediate with normal femoral arterial blood flow documented by Doppler ultrasound. NEW OR UNIQUE INFORMATION PROVIDED: This report describes use of a VCD for arterial closure following percutaneous access in a dog with impaired hemostasis; to the authors' knowledge, this is the first clinical report of a VCD used in a veterinary species.

Thromboelastometric evaluation of horses submitted to experimental thrombosis and jugular thrombectomy / Avaliação tromboelastométrica de equinos submetidos a trombose e trombectomia jugular experimental

Jugular thrombosis in horses occurs commonly in iatrogenic situations, secondary to endotoxemic clinical condition and disseminated vascular coagulation, potentially leading to death. Thus, hemostatic evaluation becomes necessary and extremely important for monitoring the risks of systemic hypercoagulability and for the efficiency of allopathic and surgical treatment. This paper describes the hemostatic behavior in experimental jugular thrombosis of ten healthy equines, subsequently submitted to two thrombectomy techniques and receiving heparin sodium as anti-rethrombosis therapy. These animals were evaluated for 20 days by thromboelastometry (TEM), platelet count, hematocrit and fibrinogen, at four moments: pre-induction to phlebitis (D0-MPF); three days after thrombophlebitis induction (D3-MFM); 6 days after, - moment of thrombophlebitis - (D9-MT); and 54 (D16) and 126 (D19) hours after thrombectomies (PTM). Thrombectomy was performed via a Vollmar Ring (group 1, n=5) and Fogarty catheter (group 2, n=5). All the animals received heparin (150 UI/kg, SC) every 12 hours, for ten days after the respective thrombectomies. Through the blood samples were evaluated TEM, activated partial thromboplastin time (aPTT) and prothrombin time (PT), dosing of fibrinogen, hematocrit and platelet count at the abovementioned moments. For comparison between groups and moments the t test was applied at 5% significance level. No significant difference was verified between treatment groups at any of the moments. There were reductions in clotting time (CT) and clot formation time (CFT), with increase in maximum lysis (ML) until the moment D9-MT. Evaluation through INTEM® reagent presented prolongations of CT and CFT with reduction of α angle and ML starting from D16 and D19. Similarly, aPTT presented significant differences between moments pre- (D0, 3 and 9) and post- (D16 and 19) anticoagulant and surgical treatment. The platelet numbers were diminished at moments D16 and D19. In evaluation with EXTEM® reagent, prolongation of CT and CFT occurred only between the moments D0 vs. D3 and vs. D9. O PT did not present significant differences. The results obtained demonstrate that experimental jugular thrombophlebitis leads to local clinical alterations, with impairment of tissue and of the extrinsic coagulation pathway (EXTEM® ), but without evidence of systemic hypercoagulability status, since there was no increase of the alpha angle or maximum clot firmness (MCF). Furthermore, TEM was shown useful and more sensitive than conventional coagulation tests (PT, aPTT and fibrinogen) for the monitoring of anticoagulant therapy, as demonstrated in other works.(AU)

A trombose jugular nos equinos ocorre comumente em situações iatrogênicas, secundárias a quadros endotoxêmicos e a coagulação vascular disseminada, podendo levar ao óbito. Por isso, avaliação hemostática se faz necessária e de extrema importância para monitorar os riscos de hipercoagulabilidade sistêmica e também a eficiência do tratamento alopático e cirúrgico. Este trabalho descreve o comportamento hemostático na trombose jugular experimental de dez equinos hígidos, submetidos posteriormente a duas técnicas de trombectomia e recebendo heparina sódica como terapia anti retrombosante. Estes animais foram avaliados durante 20 dias por tromboelastometria (TEM), contagem de plaquetas, hematócrito e fibrinogênio, em quatro momentos: pré-indução à flebite (D0-MPF); três dias após a indução da tromboflebite (D3-MFM); 6 dias após, - momento de tromboflebite - (D9-MT); e 54 (D16) e 126 (D19) horas após as trombectomias (MPT). A trombectomia foi realizada com Anel de Vollmar (grupo 1, n=5) e cateter de Fogarty (grupo 2, n=5). Todos os animais receberam heparina (150 UI/Kg, SC) a cada 12 horas, durante dez dias após as respectivas trombectomias. Através de amostras de sangue, foram avaliadas a TEM, o tempo de tromboplastia parcial ativada (TTPa) e tempo de protrombina (TP), a dosagem de fibrinogênio, hematócrito e contagem de plaquetas nos momentos descritos acima. Para a comparação entre os grupos e momentos foi aplicado teste t, com nível de significância de 5%. Não foi verificada diferença significativa entre os grupos de tratamento em nenhum dos momentos. Houve redução do tempo de coagulação (CT) e do tempo de formação do coágulo (CFT), com aumento da lise máxima (LM) até o momento D9-MT. A avaliação com o reagente intem apresentou prolongamento do CT e do CFT e redução do ângulo α e da LM a partir do D16 e D19. Da mesma forma, o TTPa apresentou diferenças significativas entre os momentos pré (D0, 3 e 9) e pós (D16 e 19) tratamento cirúrgico e anticoagulante. Houve diminuição do número de plaquetas nos momentos D16 e D19. Na avaliação com reagente extem ocorreu apenas o prolongamento do CT e CFT entre os momentos D0 e o D3 e D9. O TP não apresentou diferenças significativas. Os resultados obtidos demonstram que a tromboflebite jugular experimental leva a alterações clínicas locais, com comprometimento tecidual e da via extrínseca da coagulação (extem), porém sem evidências de um estado sistêmico de hipercoagulabilidade, pois não houve aumento do ângulo alfa e da firmeza máxima do coágulo (MCF). Além disso, a TEM se mostrou útil e mais sensível que os testes convencionais de coagulação (TP, TTPa e fibrinogênio) para o acompanhamento da terapia anticoagulante, conforme demonstrado em outros trabalhos.(AU)

Hemostasia e incisão do pedículo ovariano de gatas submetidas à ovariossalpingo-histerectomia eletiva por meio da técnica das três pinças ou do eletrobisturi bipolaar. Estudo comparativo / Hemostasis and incision into the ovary pedicle of cats undergone elective ovariosalpingohysterectomy using the technique of the three bipolar forceps or eletrobisturi. Comparative study

Na cirurgia de ovariossalpingo-histerectomia (OSH), há várias técnicas para realização da hemostasia e da secção do pedículo ovariano, sendo mais comum a técnica das três pinças. O eletrobisturi bipolar pode ser utilizado com eficácia para hemostasia e corte de tecidos. Objetivou-se nesta pesquisa comparar, em gatas, a hemostasia e a secção do pedículo ovariano mediante o uso do eletrobisturi bipolar com a técnica das três pinças, ambas via celiotomia mediana, em relação ao tempo cirúrgico e à eficiência hemostática (hematócrito). Quarenta gatas, com idade de seis meses a sete anos, peso entre 1,68 e 4,14kg, foram submetidas à hemostasia e à secção desse pedículo, sendo 20 pela técnica convencional e 20 por meio do eletrobisturi bipolar. Na análise estatística, observou-se que o uso do eletrobisturi bipolar gera uma diminuição média significativa na duração da cirurgia, quando comparado com o outro método, sem diferenças quanto à comparação de hematócritos pré e pós-cirúrgicos. Por meio do modelo de regressão múltiplo, verificou-se que as variáveis: idade, peso, número de gestações, número de partos e número de cios não influenciaram significativamente no tempo. Concluiu-se, portanto, que o eletrobisturi bipolar oferece eficiência e maior rapidez na realização da hemostasia e da diérese do pedículo ovariano de gatas submetidas à OSH eletiva...

In ovariosalpingohisterectomy (OSH) surgery, there are several techniques for hemostasis and resection of ovarian pedicle, the most common being the three tweezers technique. The bipolar eletrobisturi can be used effectively for hemostasis and cutting tissue. The aim of this research was to compare, in cats, hemostasis and resection of ovarian pedicle eletrobisturi with bipolar forceps and the three techniques, both via median celiotomy, in relation to time and surgical hemostatic efficiency (hematocrit). Forty cats aged six months to seven years, weighing between 1.68 and 4.14kg, underwent hemostasis and pedicle of this section, 20 with the conventional technique and 20 with eletrobisturi bipolar. Statistical analysis showed that the use of bipolar eletrobisturi generates a significant decrease in the mean duration of surgery when compared with a method without differences in hematocrit comparing pre-and post-surgery. Through the multiple regression model we found that the variables age, weight, number of pregnancies, number of births and number of cycles did not significantly influence the time. We conclude, therefore, that the bipolar eletrobisturi is efficient and fast for hemostasis and dieresis ovarian pedicle of cats undergoing elective ovariohysterectomy...

Effects of 6% hetastarch (600/0.75) or lactated Ringer's solution on hemostatic variables and clinical bleeding in healthy dogs anesthetized for orthopedic surgery.

OBJECTIVE: To evaluate and compare hemostatic variables and clinical bleeding following the administration of 6% hetastarch (600/0.75) or lactated Ringer's solution (LRS) to dogs anesthetized for orthopedic surgery. STUDY DESIGN: Randomized blinded prospective study. ANIMALS: Fourteen, healthy adult mixed-breed hound dogs of either sex, aged 11-13 months, and weighing 20.8±1.2 kg. METHODS: The dogs were randomly assigned to receive a 10 mL kg(-1) intravenous (i.v.) bolus of either 6% hetastarch (600/0.75) or LRS over 20 minutes followed by a maintenance infusion of LRS (10 mL kg(-1)  hour(-1)) during anesthesia. Before (Baseline) and at 1 and 24 hours after bolus administration, packed cell volume (PCV), total protein concentration (TP), prothrombin time (PT), activated partial thromboplastin time (APTT), von Willebrand's factor antigen concentration (vWF:Ag), factor VIII coagulant activity (F VIII:C), platelet count, platelet aggregation, colloid osmotic pressure (COP) and buccal mucosal bleeding time (BMBT) were measured. In addition a surgeon who was blinded to the treatments assessed bleeding from the incision site during the procedure and at 1 and 24 hours after the bolus administration. RESULTS: Following hetastarch or LRS administration, the PCV and TP decreased significantly 1-hour post-infusion. APTT did not change significantly compared to baseline in either treatment group, but the PT was significantly longer at 1-hour post-infusion than at 24 hours in both groups. No significant change was detected for vWF:Ag, FVIII:C, platelet aggregation or clinical bleeding in either group. The BMBT increased while platelet count decreased significantly at 1-hour post-infusion in both groups. The COP decreased significantly in both treatment groups 1-hour post-infusion but was significantly higher 1-hour post-infusion in the hetastarch group compared to the LRS group. CONCLUSIONS AND CLINICAL RELEVANCE: At the doses administered, both hetastarch and LRS can alter hemostatic variables in healthy dogs. However, in these dogs undergoing orthopedic surgery, neither fluid was associated with increased clinical bleeding.

Diagnosis and treatment of secondary anticoagulant rodenticide toxicosis in a red-tailed hawk (Buteo jamaicensis).

Anticoagulant rodenticides inhibit the activation of vitamin K-ependent clotting factors, resulting in fatal hemorrhage. Nontarget species are exposed to these rodenticides primarily by direct consumption of baits or secondarily by consumption of poisoned prey. The diagnosis of anticoagulant rodenticide toxicosis is more challenging in birds than in mammals because of the limited availability of laboratory tests to evaluate avian coagulation. In addition, the presenting signs in birds may differ from those commonly seen in mammals. Treatment for acute blood loss and therapy with vitamin K1 can result in a favorable outcome in birds. This report describes the presenting signs, diagnosis, and successful treatment of a red-tailed hawk (Buteo jamaicensis) with secondary anticoagulant rodenticide toxicosis.

Evaluation of a vessel-sealing device for laparoscopic granulosa cell tumor removal in standing mares.

OBJECTIVE: To describe a laparoscopic technique for granulosa cell tumor removal using a vessel sealing device (LigaSuretrade mark) in standing mares. STUDY DESIGN: Retrospective study. ANIMALS: Eight mares (8-24 years old; weighing, 406-525 kg). METHODS: Before surgery, ovarian size and adjacent body wall thickness was determined by ultrasonography. Mares were sedated and after local anesthesia (inverted L and local infiltration), laparoscopic cannulation was performed without insufflation. The mesovarium was anesthetized and the LigaSure instrument applied to the mesovarium for hemostasis and resection to remove the affected ovary. Mares were hospitalized for 24 hours before discharge. RESULTS: Median ovarian diameter was 10.5 cm (range, 6-14 cm). Median surgery time was 75 minutes (range, 40-180 minutes). Hemostasis was achieved using the LigaSure device in all mares. Median length of the abdominal wall incision made to remove the ovary was 13 cm (range, 5-17 cm); no incisional complications occurred. CONCLUSIONS: The LigaSure vessel sealing device provided adequate hemostasis for removal of larger neoplastic ovaries in standing mares. CLINICAL RELEVANCE: Concerns of ligature placement can be alleviated by use of the LigaSure device and standing laparoscopic technique provides excellent observation of the surgical field ensuring hemostasis.

Assessment of platelet function in horses: ultrastructure, flow cytometry, and perfusion techniques.

We studied equine platelet function and activation using ultrastructural examination, flow cytometry, and perfusion. The main aim of the study was to evaluate hemostatic mechanisms in horses using these techniques. Ultrastructural observations were done on resting and activated platelets. Flow cytometry was used to evaluate binding of antibodies to major platelet glycoproteins (GPIIb-IIIa, GPIV, and GPIb) and activation-dependent antigens (P-selectin and lysosomal integral membrane protein [LIMP]). Perfusion techniques were used to evaluate the interaction between platelets and damaged subendothelium. Aggregation experiments were done to identify the best agonists for flow cytometry. Ultrastructural observations confirmed that equine platelets lack a developed open canalicular system and that release of granule contents occurs by fusion of adjacent granule membranes that ultimately connect with external membranes. Flow cytometry identified a 2-fold increase in binding of antibodies against GPIIb-IIIa and GPIV after activation. Binding of antibodies against P-selectin and LIMP increased from 2.12 and 1.74% to 15.5 and 11.6%, respectively, in response to thrombin and to 21.86 and 10.50%, respectively, in response to collagen. Annexin V binding increased moderately after activation. Perfusion experiments with citrated blood indicated that equine platelets react more strongly to subendothelium than do human platelets. When blood was anticoagulated with low molecular weight heparin, a marked impairment of platelet interactions was observed. In conclusion, although some differences were observed between human and equine platelet function, some techniques currently used to assess human platelet function may be useful to assess equine platelets.

Evaluation of a novel hemostatic device in an ovine parenchymal organ bleeding model of normal and impaired hemostasis.

Bleeding is a problem encountered by many surgeons, often complicated by the presence of coagulopathy or anticoagulant. The hemostatic effectiveness of CoStasis Surgical Hemostat (with bovine collagen, bovine thrombin, and autologous plasma) was evaluated and compared to a collagen sponge and to two investigational fibrin-sealant preparations under conditions of normal and impaired coagulation. A liver resection and controlled incisions in spleens and kidneys were made in sheep. Time to complete hemostasis and total blood loss were measured. Tissue response was evaluated at 7, 30, 60, and 75 days. CoStasis-treated sites demonstrated significantly shorter time to hemostasis (all surgical sites combined) compared with fibrin sealant (investigational fibrin sealant 1) (p= .005) or collagen sponge (p=0.013). In anticoagulated animals, CoStasis and fibrin sealant (investigational fibrin sealant 2) had comparable mean times to hemostasis, and CoStasis-treated sites exhibited lowered average blood loss compared to investigational fibrin-sealant-2 treated sites. CoStasis-treated sites demonstrated higher levels of tissue repair (lower inflammation, more extensive tissue repair, and less residual implant) compared to fibrin-sealant- or collagen-sponge-treated sites in Phases I and II. These findings demonstrate that CoStasis is a highly effective hemostatic agent for control of bleeding from parenchymal organs. Furthermore, under conditions of compromised coagulation, treatment with CoStasis demonstrates a reduction in average blood loss when compared to treatment with fibrin sealant.

An evaluation of the haemostatic suture in hysterotomy closure in the mare.

This study was designed to evaluate the haemostatic suture as a means of preventing haemorrhage from the hysterotomy in mares after caesarean section. At 2 university hospitals 1982-1994, 48 mares had caesarean section for dystocia, 10 as an elective, and 8 mares concurrently with colic surgery. The haemostatic suture was used in 31 of 66 mares (47%) and surgery period was significantly (P<0.05) shorter when it was not applied. Anaemia (PCV<30%) was recorded in 13 (22%) of 58 mares, excluding the colic group, and the haemostatic suture did not after this proportion of mares that had anaemia. Anaemia was 5 times more probable following caesarean section than vaginal delivery, evidence that bleeding from the hysterotomy is a serious and common complication of caesarean section in mares. Severe uterine haemorrhage was recorded in 3 mares that had an haemostatic suture (10%) and in 2 mares that did not (6%). The latter two mares died of haemorrhage. The suture, therefore did not eliminate post operative anaemia and severe uterine haemorrhage. If omitted, the hysterotomy should be closed with a full thickness pattern that is sufficiently tight to compress vessels in the uterine wall.

Evaluation of a hemostasis model for teaching basic surgical skills.

The need for alternative methods of teaching veterinary medicine and surgery has increased in recent years because of increasing costs and changing public opinion. For these reasons a hemostasis model was developed that mimics the arteries and veins of the peripheral vascular system, and can be used to teach the basic skills involved in blood vessel ligation and division. This study evaluated the effectiveness of the fluid hemostasis model compared with using live animals for teaching these skills. Forty sophomore veterinary students participated in the study. Two groups of 20 students each received identical instruction in the basic techniques required for vessel ligation and division. The students then completed various exercises using inanimate models to objectively evaluate their psychomotor skills. Both groups then practiced the techniques for equal time periods; one group used the hemostasis model and the other performed a splenectomy on live dogs. After the practice session, the students were videotaped (for later evaluation), as they performed vessel ligations and divisions. The students then repeated the exercises using the inanimate models for evaluation of skills improvement. Questionnaire responses before and after the project were obtained to determine the students' views on the need for inanimate models for teaching purposes. Results of this study indicate that the hemostasis model was as effective as live animals for teaching the basic skills involved in blood vessel ligation. The students' opinions regarding the use of properly designed inanimate models for teaching these skills were dramatically changed.