Effects of exploratory laparotomy on plasma and peritoneal coagulation/fibrinolysis in horses

Plasma and peritoneal fluid samples were collected before and after surgery from 6 horses undergoing a ventral midline exploratory laparotomy and from 6 anesthetized control horses. Coagulation/fibrinolytic components measured in the plasma and peritoneal fluid of these horses included the functional activity of antithrombin III, alpha-2 antiplasmin, plasminogen, and protein C, and the concentrations of fibrinogen and fibrin degradation products. Peritoneal fluid antithrombin III, fibrin degradation products, and plasminogen values were significantly increased after surgery (over time) in principal horses. Compared with control horses, postoperative peritoneal fluid from horses undergoing laparotomy had significantly increased antithrombin-III activity at 12 and 72 hours, alpha-2 antiplasmin activity at 24 hours, fibrin degradation product concentrations at 6, 12, 24, 72, 96, and 144 hours, plasminogen activity at 6, 12, 24, 48, 72 and 96 hours, and protein-C activity at 12, 24, 72, and 96 hours. There were no significant changes in the peritoneal fibrinogen concentration in principal horses. Plasma plasminogen activity was significantly decreased at 24 hours after surgery in principal horses, compared with controls. Changes were minimal in the remaining plasma coagulation/fibrinolytic components of horses undergoing laparotomy. Plasma and peritoneal fluid values of anesthetized control horses did not change.     

Severe hypercarbia resulting from inspiratory valve malfunction in two anesthetized horses

Severe hypercarbia was documented by arterial blood gas analysis in 2 adult horses anesthetized for exploratory laparotomy. Both horses appeared to be adequately anesthetized, but continued to breathe against the ventilator. In both cases, the inspiratory valve on the anesthesia machine was found to be stuck open, permitting expired CO2 to return to the inspiratory limb of the anesthetic circuit and to be inhaled with the next breath. Correction of the malfunctioning valve alleviated the hypercarbia. Problems with the flow valves of the anesthesia machine should be suspected when anesthetized horses breathe against the ventilator and develop severe hypercarbia.     

Diaphragmatic hernia in horses: 44 cases (1986–2006)

Objectives – To present a case series of horses diagnosed with diaphragmatic hernia, and to determine the significance of (1) historical information, examination findings, and laboratory data; and (2) exploratory laparotomy or necropsy findings on short- and long-term outcome.
Setting – University Referral Hospital.
Design – Retrospective study.
Animals – Forty-four horses/foals admitted between 1986 and 2006 with a diagnosis of diaphragmatic hernia made either at exploratory laparotomy or necropsy.
Interventions – None.
Measurements and Main Results – Information from the medical records included history, clinical examination findings at presentation, and findings of exploratory laparotomy or necropsy. Logistic regression or the Fisher exact test was used to determine factors associated with survival. Outcome was defined as survival to discharge (short-term survival), and long-term survival was defined as horses alive at least 1-year post surgery. Of the 44 horses, 18 died or were euthanized before surgery. Twenty-six were taken to surgery, 17 were euthanized. Nine horses recovered from anesthesia, 7 of which survived to hospital discharge. Of these, 5 were alive at long-term follow-up. Survival was significantly associated with the age of the horse (≤2 y old) at presentation, presence of normal peritoneal fluid at presentation, amount of compromised viscera at surgery (<50% small intestine), and the size (<10 cm) and location (ventral) of the diaphragmatic tear.
Conclusion – This study confirms that size and location of the lesion do play a significant role in prognosis. And, although the prognosis for horses with diaphragmatic hernia is poor, if horses have operable lesions there is a fair prognosis for long-term survival.     

Short-Term Effects of Duodenocecostomy on Body Weight,Glucose Absorption,Serum Components,and Intestinal Histopathology in Four Normal Horses

The objective of this study was to evaluate duodenocecostomy in horses performed through a ventral midline laparotomy and report its influence on body weight, glucose absorption, serum components, and characteristics of jejunum, cecum, and large colon histology. Four horses were submitted to the duodenocecostomy technique through a ventral midline laparotomy with animals in dorsal recumbency under inhalation anesthesia, followed by abdominal exploration. A side-to-side anastomosis was performed between the duodenojejunal flexure and the base of the cecum with two simple continuous suture lines of the serosal and muscular layers. The size of the opening created was approximately 2 cm in diameter. The mucosa layer was not sutured. After 30 days, animals were submitted to a second laparotomy to check the patency of the duodenocaecal fistula. During both laparotomy procedures, excisional biopsies of different segments of the gastrointestinal tract were performed. Information on physical examination findings, results of hematologic and histopathologic evaluations, and oral glucose absorption test were recorded. The horses did not have significant weight loss from baseline, and absorption curve of glucose did not significantly vary from baseline. Only triglycerides had significant alterations. Histologic evaluation of jejunum, cecum, and large colon did not show alterations of intestinal structure and morphology. We concluded that the proposed technique, principally in relation to the fistula size and not suturing the mucosa layer, allowed partial or total occlusion of the fistulae without the necessity of a second surgery and avoided the permanent bypass of ingesta and weight loss.     

Retrospective Identification of Bacterial Isolates From Emergency Laparotomy Surgical Site Infections in Horses

Surgical site infection (SSI) with multiresistant bacteria is an important cause of postoperative morbidity after laparotomy in horses. The objective of this study was to identify bacteria isolates and their antibiotic resistance patterns associated with the development of wound infection in horses after laparotomy. This is a retrospective case series. Medical records of horses that underwent ventral midline exploratory laparotomy in a four-year period at one equine hospital were reviewed. Results of microbiologic culture and susceptibility testing are described. The study group consisted of 183 (100%) horses that recovered from anesthesia after laparotomy. The prevalence of infection was 19% (24/124) after first surgery and 83% (19/23) after relaparotomy. The most common microbial isolates were bacteria of the family Enterobacteriaceae followed by Staphylococcus ssp., Enterococcus ssp., Streptococcus ssp., and Bacteroides ssp. Bacteria from the family Enterobacteriaceae showed the lowest resistance to amphenicols, cephalosporins, and quinolones groups of antibiotics. Coagulase-positive Staphylococci were sensitive to amphenicols and only 33% were resistant to trimethoprim/sulfamethoxazole. The most commonly used perioperative and postoperative antibiotics were gentamicin and amoxicillin. Limitations include poor control over exposure factors, covariates, and potential confounders during the surgery, recovery time, or period of hospitalization; relying on others for accurate outcome assessment and recordkeeping; lack of follow-up information once animals were discharged from the hospital. Despite 5 days of antibiotic prophylaxis, the rate of incisional infection is still high. The most common isolates from SSI belong to the family Enterobacteriaceae and the genus Staphylococcus, which showed high resistance to the antibiotics used before the gastrointestinal surgery.     

Difference in incisional complications following exploratory celiotomies using antibacterial‐coated suture material for subcutaneous closure: Prospective randomised study in 100 horses

Reasons for performing study: Incisional complications are a major post operative challenge following ventral midline exploratory celiotomy for abdominal pain in horses. They lead to discomfort, prolonged hospitalisation, longer recovery times and increased cost; therefore, investigation of preventative procedures are warranted. Objectives: To determine the clinical effect of antibacterial (triclosan) coated 2‐0 polyglactin 910 suture material on the likelihood of incisional infections when used for closure of subcutaneous tissue following ventral midline celiotomies in horses. Methods: One hundred horses undergoing exploratory celiotomy assigned at random to one of 2 groups. In the control group coated 2‐0 polyglactin 910 (Vicryl) was used for apposition of the subcutaneous tissue in a simple continuous pattern and, in the study group, antibacterial (triclosan) coated 2‐0 polyglactin 910 suture material (Vicryl Plus) was used. Post operatively an elastic adhesive abdominal bandage was applied, changed and the incision was inspected by a clinician blinded to the study protocol at 24–36 h and 6–9 days post operatively. Outcomes of interest were evidence of incisional pain, incisional oedema, sheath/udder oedema, incisional drainage, hernia formation and dehiscence. Results: Antibacterial‐coated suture material did not decrease the likelihood of incisional complications in 100 horses. Conclusions: A beneficial effect on ventral midline incisions in 100 horses was not evident by using antibacterial‐coated suture material. Potential relevance: Lack of effectiveness of antibacterial‐coated suture material in equine ventral midline closure after exploratory celiotomy and the observed potential adverse effects suggest that further clinical investigations are needed before using such material routinely on horses.     

Prolonged anesthesia with desflurane and fentanyl in dogs during conventional and laparoscopic surgery

OBJECTIVE: To determine the effects of prolonged anesthesia with desflurane in dogs undergoing laparotomy or abdominal laparoscopy. DESIGN: Randomized prospective study. ANIMALS: 20 adult mixed-breed dogs. PROCEDURE: Dogs were randomly assigned to 1 of 2 groups with 10 dogs/group. Anesthesia was induced with propofol and maintained with desflurane and fentanyl, and pyloroplasty was performed. In 10 dogs, a ventral midline laparotomy was performed; in the other 10, abdominal laparoscopy was performed. Dogs were monitored for cardiovascular and respiratory responses (ECG, oxygen saturation [SpO2], arterial blood pressure, rectal temperature, end-tidal partial pressure of carbon dioxide [PETCO2], and expired desflurane concentration). Recovery times were recorded. RESULTS: Mean +/- SD duration of anesthesia was 201 +/- 25 minutes for dogs undergoing laparotomy and 287 +/- 15 minutes for dogs undergoing laparoscopy. Anesthesia was accompanied by hypotension that was less severe in dogs undergoing laparoscopy. Heart rate did not vary significantly during anesthesia. The SpO2 was > 97% in all dogs at all times, and PETCO2 remained within reference limits. Recovery times for dogs that underwent laparotomy were not significantly different from those for dogs that underwent laparoscopy. Mean +/- SD time to standing was 13.6 +/- 2.4 minutes for dogs that underwent laparotomy and 12.5 +/- 2.9 minutes for dogs that underwent laparoscopy. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that induction of anesthesia with propofol and maintenance with desflurane and fentanyl is safe in dogs undergoing abdominal surgery.     

Results of surgical treatment of colic in miniature breed horses: 11 cases

OBJECTIVE: To report on the outcome of surgical treatment of acute abdominal crises in miniature breed horses. DESIGN: Retrospective case series of miniature horses presented to the University Veterinary Centre, Camden with an acute abdominal crisis. METHODS: Hospital records of all miniature horses that underwent ventral midline laparotomy for acute abdominal crisis between 1997 and 2001 were reviewed. The signalment, history, clinical signs, results of ancillary diagnostic procedures, location and type of intestinal lesion, treatment and outcome were retrieved from each case record. Long-term survival was determined by telephone interview of owners. RESULTS: Eleven miniature horses including five females and six males underwent ventral midline laparotomies for acute abdominal crisis during the study period. Ages ranged between 1 month and 19 years. Surgical findings included faecalith obstruction (seven horses), enterolith (one horse), strangulating lipoma of the descending colon (one horse), jejunal infarction (one horse), and caecal infarction (one horse). Long-term survival rate (minimum 12 months post surgery) was 55%. Six of eight horses with simple intraluminal obstructions survived, while the three horses with gastrointestinal lesions associated with vascular compromise were euthanased either at surgery (caecal infarction), or postoperatively, due to complications (strangulating lipoma of the descending colon, jejunal infarction). Postoperative complications in this study included impaction of the descending colon (two horses), diarrhoea (two horses), peritonitis (one horse), hyperlipaemia (two horses), incisional infection (two horses) and abdominal adhesions (one horse). Hyperlipidaemia was present in five of seven horses in which serum triglycerides were measured at presentation. CONCLUSIONS: Simple intraluminal obstructions of the large intestine were frequently encountered during exploratory laparotomy in miniature horses presented for acute abdominal crises, and their surgical treatment was associated with a good prognosis. In contrast, this study suggested that abdominal pain associated with vascular compromise of gastrointestinal tissues in miniature horses was associated with a poorer prognosis, consistent with reports in other horse breeds. Possible contributing factors to faecalith formation, including poor quality roughage, dental disease, and inadequate water consumption, should be recognised and avoided in miniature horses. Serum triglyceride concentrations should be measured in miniature horses presented for acute abdominal pain. If elevated, nutritional supplementation should be provided.     

Successful treatment of two horses after perforation of the small intestine by fine wire

This paper describes the successful surgical management of two horses with fine wire penetration of the small intestine. Exploratory laparotomy in Case 1 revealed an adhesion between adjacent loops of jejunum. Dissection of the adhesion revealed a small length of fine wire. In Case 2, exploratory laparotomy revealed a dense adhesion between the jejunum and the ventral abdominal wall. Dissection of the adhesion also revealed fine wire extending from the jejunum. Neither case required intestinal resection, and both horses made uncomplicated recoveries from the surgical procedures and were discharged 5 days after surgery.     

Do subcutaneous sutures increase risk of laparotomy wound suppuration?

REASONS FOR PERFORMING STUDY: Incisional drainage and suppuration occurs commonly following exploratory laparotomy; any technique with the potential to reduce the incidence of this complication warrants investigation. OBJECTIVES: To determine if abandoning the use of subcutaneous sutures in laparotomy wound closure is safe and whether it reduces the risk of suppuration. METHODS: A randomised controlled study was carried out at 2 referral hospitals in the UK, involving 309 horses undergoing exploratory laparotomy; 150 horses underwent '2-layer' closure without a subcutaneous suture, while 159 underwent conventional '3-layer' closure. Information regarding degree of oedema and gross types of discharge was recorded daily; suppuration was defined as discharge of pus. Telephone follow-up was carried out 30 days after hospital discharge to identify those complications occurring after that date and, thereafter, every 3 months. The influence of closure method on risk of wound suppuration was assessed by Chi-squared analysis and by logistic regression. Time to suppuration was modelled using a Cox proportional hazards model. RESULTS: No catastrophic failures of 2-layer closures were recorded. Prevalence of suppuration was not significantly different, being 18.7% and 23.9% for 2- and 3-layer closures, respectively (OR = 1.37, 0.79-2.37, P = 0.263). CONCLUSIONS AND POTENTIAL RELEVANCE: This study found no significant difference in prevalence or rate of wound suppuration in 2-layer closures compared to conventional 3-layer closure. Two-layer closure is recommended as a safe alternative means of achieving ventral midline abdominal closure in horses.     

Effects of warm-up intensity on kinetics of oxygen consumption and carbon dioxide production during high-intensity exercise in horses

OBJECTIVE: To compare effects of low and high intensity warm-up exercise on oxygen consumption (VO2) and carbon dioxide production (VCO2) in horses. ANIMALS: 6 moderately conditioned adult Standard-breds. PROCEDURES: Horses ran for 2 minutes at 115% of maximum oxygen consumption (VO2max), 5 minutes after each of the following periods: no warm-up (NoWU); 10 minutes at 50% of VO2max (LoWU); or 7 minutes at 50% VO2max followed by 45-second intervals at 80, 90, and 100% VO2max (HiWU). Oxygen consumption and VCO2 were measured during exercise, and kinetics of VO2 and VCO2 were calculated. Accumulated O2 deficit was also calculated. RESULTS: For both warm-up trials, the time constant for the rapid exponential increase in VO2 was 30% lower than for NoWU. Similarly, the rate of increase in VCO2 was 23% faster in LoWU and HiWU than in NoWU. Peak values for VO2 achieved during the high-speed test were not significantly different among trials (LoWU, 150.2 +/- 3.2 ml/kg/min; HiWU, 151.2 +/- 4.2 ml/kg/min; NoWU, 145.1 +/- 4.1 ml/kg/min). However, accumulated O2 deficit (ml of O2 equivalents/kg) was significantly lower during LoWU (65.3 +/- 5.1) and HiWU (63.4 +/- 3.9) than during NoWU (82.1 +/- 7.3). CONCLUSIONS AND CLINICAL RELEVANCE: Both the low- and high-intensity warm-up, completed 5 minutes before the start of high-intensity exercise, accelerated the kinetics of VO2 and VCO2 and decreased accumulated O2 deficit during 2 minutes of intense exertion in horses that were moderately conditioned.     

Resection cystoplasty of a squamous cell carcinoma in a mare

A 22‐year‐old Arabian mare was examined for evaluation of haematuria of 2 months' duration. Complete blood cell count and chemistry revealed anaemia of chronic disease (i.e. normocytic, normochromic) and hypoproteinaemia. Cystoscopy revealed a haemorrhagic mass protruding into the lumen of the urinary bladder in the apical region. The mass was surgically removed by partial cystectomy performed through a caudal ventral midline laparotomy. Histological examination of the mass confirmed the diagnosis of squamous cell carcinoma. Tumours of the equine urinary bladder are rare, and when a partial cystectomy is indicated, a caudal ventral midline laparotomy may provide adequate surgical exposure even in adult horses.     

Bacterial Culturing of Ventral Median Celiotomies for Prediction of Postoperative Incisional Complications in Horses

Objective - The purpose of this study was to determine whether detection of bacterial contamination of ventral midline incisions was predictive of postoperative incisional complications in horses undergoing exploratory celiotomy for colic. Study Design - Prospective study. Animal or Sample Population - Horses that had ventral median celiotomies for colic at Colorado State University between May 1, 1991 and April 30, 1993 were studied prospectively. Complete information was obtained on 66 horses. Methods - Bacterial cultures were obtained from ventral midline incisions at surgery. Information regarding the type of surgery performed (celiotomy vs celiotomy plus enterotomy or enterectomy), preoperative total nucleated cells and presence of a left shift, postoperative fever (>38.5°C), incisional drainage, incisional herniation, and outcome were obtained from medical records. Additional information concerning incisional drainage, herniation, and survival was obtained at a minimum of 18 months after surgery. Results - Examination of odds ratio (ORs) and confidence intervals (CIs) revealed that a celiotomy plus enterotomy or enterectomy was positively, but not significantly, associated (OR > 1) with positive culture results, presence of incisional drainage and incisional herniation. A significant association between incisional drainage and hernia formation was found; odds of incisional herniation were 62.5 times greater in horses that had incisional drainage. Incisional drainage and herniation were negatively associated with patient survival. The later association was significant (OR = 0.18, P=.04). Conclusions - This study indicated that detection of bacterial contamination at incisional closure by the swab culture technique was not beneficial in the prediction of postoperative incisional problems in horses undergoing colic surgery. Incisional drainage or infection appeared to be associated with hernia formation. Clinical Relevance - Immediate treatment of incisional drainage or methods to prevent incisional infections may decrease hernia formation.     

Small-intestinal volvulus as a complication of acquired inguinal hernia in two horses

Volvulus of the small intestine was diagnosed as a complication of acquired inguinal herniation in 2 horses. One of the horses continued to have signs of pain after reduction of the hernia. The volvulus was diagnosed at a second surgery, but the intestine was devitalized, and the horse was euthanatized. Ventral midline exploratory surgery was performed on the second horse, in conjunction with an inguinal approach. The small-intestinal volvulus was diagnosed and corrected at this time. It is suggested that ventral midline abdominal exploration be performed when acquired inguinal herniation causes acute small-intestinal obstruction in horses.     

Colopexy of the equine large colon: comparison of two techniques

A study was designed to evaluate 2 colopexy techniques (A and B) in 8 clinically normal horses to determine which technique would prevent recurrence of large-colon displacement and/or volvulus. For technique A, 35 cm of the lateral free band of the left ventral colon was sutured to the abdominal wall, 6 cm to the left of ventral midline. For technique B, the medial free band of the left ventral colon was sutured to the medial free band of the right ventral colon, and 8 cm of the lateral free band of the left ventral colon was sutured to the abdominal wall, 6 cm to the left of ventral midline. One horse from each group was euthanatized at 6 months, and another at 12 months after surgery. The position of the large colon, the integrity of the colopexy, and other adhesions within the abdominal cavity were evaluated. At necropsy, attempts were made to manually create displacement and volvulus of the large colon. The remaining horses in each group were anesthetized 6 months or 12 months after surgery, and the integrity of the colopexy was evaluated. After a 60-day recovery period, these horses were exercised for 2 months. Although each horse initially lost weight, the weight of all but 2 was acceptable at the conclusion of the study. Two horses that had technique-B colopexies had progressive weight loss serious enough to warrant euthanasia. Both colopexy techniques prevented manual creation of large-colon displacement and large-colon volvulus centered at the sternal and diaphragmatic flexures. Technique-A colopexy also prevented manual creation of volvulus of the large colon centered at its base.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hemodynamic Responses of Horses to Anesthesia and Surgery, Before and After Administration of a Low Dose of Endotoxin

Seven horses, which were part of an investigation of the effect of endotoxin administration on vascular reactivity, were anesthetized on two separate occasions for surgical excision of 4-cm sections of palmar digital artery and vein. On the first occasion, the horses were given an infusion of 1 L 0.9% NaCl solution intravenously (IV) just before induction of anesthesia (control); on the second occasion, the horses received an infusion of 1 L 0.9% NaCl containing Escherichia coli endotoxin, 0.1 μg/kg (endotoxin). On both occasions, anesthesia was induced with xylazine, guaifenesin, and ketamine, and maintained with halothane in oxygen. Hemodynamic measurements were made with the horses under anesthesia immediately before beginning surgery (period 1), during skin incision (period 2), during dissection and excision of the vessels (period 3), during skin suturing (period 4), and after completion of surgery during bandaging (period 5). Hemoglobin concentration and mixed venous oxygen content were greater at all periods in horses that received endotoxin. Otherwise, there were no significant differences in hemodynamic parameters between control horses and horses administered endotoxin before beginning surgery (period 1). During surgery and bandaging, horses administered endotoxin had significantly higher heart rate (periods 3, 4, and 5), cardiac index (periods 3, 4, and 5), and oxygen delivery (periods 2, 3, 4, and 5) than did control horses, and mean arterial blood pressure (period 2) and systemic vascular resistance (periods 2, 3, 4, and 5) were less than in control horses. Compared with period 1, surgical stimulation in control horses was associated with increased mean arterial blood pressure and systemic vascular resistance (periods 2, 3, 4, and 5), but cardiac index and oxygen delivery were decreased (periods 3, 4, and 5). In contrast, horses administered endotoxin responded to surgical stimulation with increased mean arterial blood pressure (periods 2, 3, 4, and 5) and vascular resistance (periods 4 and 5), as well as a heart rate-induced increase in cardiac index (periods 2, 3, 4, and 5) compared with period 1; oxygen delivery also increased (periods 2, 3, 4, and 5) during surgery in the endotoxin group. This study documents some of the differences in the response to anesthesia and surgery between normal horses and those that have received endotoxin.     

Jejunoileal anastomosis following small intestinal resection in horses: seven cases (1999-2001)

OBJECTIVE: To report the postoperative outcome in horses undergoing jejunoileal anastomosis performed with a 2-layer simple continuous technique. DESIGN: Retrospective study. ANIMALS: 7 horses. PROCEDURE: Information regarding signalment, clinical signs, findings at surgery, and postoperative complications was obtained from medical records of horses that underwent exploratory ventral midline celiotomy, small intestinal resection, and jejunoileal anastomosis to correct various small intestinal strangulating lesions. Follow-up information was obtained via telephone conversations with owners or trainers. RESULTS: Six males and 1 female of various breeds aged 10 months to 27 years and weighing 312 to 785 kg (686.4 to 1,727 lb) were included. The most common complications were mild to moderate tachycardia and mild to moderate signs of abdominal pain. Two horses developed incisional infections and soft, fluctuant swelling at the incision site following resolution of the infection. Follow-up time ranged from 7 to 17 months after surgery. Owners reported no further colic episodes and no diet change necessary following surgery. All horses had returned to their intended level of use. CONCLUSIONS AND CLINICAL RELEVANCE: Advantages to the jejunoileal technique include maintaining the normal ileocecal valve and a postoperative recovery period similar to that described following other small intestinal anastomoses. Jejunoileal anastomosis is a viable alternative to ileal bypass. This technique appears to result in a postoperative complication rate similar to that reported following jejunojejunostomy procedures.     

Evaluation of iodophor skin preparation techniques and factors influencing drainage from ventral midline incisions in horses.

OBJECTIVE: To document natural bacterial flora on the ventral aspect of the equine abdomen, to compare 2 preparation techniques, and to identify potential risk factors that may contribute to incisional drainage. DESIGN: Prospective study. ANIMALS: 53 horses undergoing exploratory celiotomy. PROCEDURE: Group-1 horses (n = 26) were prepared with povidone-iodine and alcohol. Group-2 horses (27) were prepared with a film-forming iodophor complex. Numbers of bacterial colony-forming units (CFU) were measured before and after surgical scrub, following skin closure, and after recovery from general anesthesia. Swab specimens to identify normal skin bacterial flora and potential pathogens were obtained by swabbing a 4 x 4-cm area. Variables that might affect incisional drainage were also investigated. RESULTS: For both techniques, there was a significant reduction in bacterial numbers after skin preparation. Incisional drainage was observed in 14 (26%) horses (8 group-1 and 6 group-2 horses). Preexisting dermatitis, poor intraoperative drape adherence, high number of bacterial CFU obtained after recovery from anesthesia, and high number of CFU obtained from the surgery room environment were the main risk factors associated with subsequent incisional drainage. Bacillus spp, nonhemolytic Staphylococcus spp, Micrococcus spp, Corynebacterium spp, Streptomyces spp, other nonenteric genera, and nonhemolytic Streptococcus spp were the most common isolates obtained before surgical scrub. CONCLUSIONS AND CLINICAL RELEVANCE: Both skin preparation techniques were equally effective in reducing numbers of bacterial CFU by 99%, and a significant difference was not found in incisional drainage rate between groups. Protection of the wound during recovery from anesthesia and the immediate postoperative period may reduce incisional drainage after abdominal surgery in horses.     

Standing flank laparotomy for the treatment of small colon impactions in 15 ponies and one horse

Impactions are the most common problem affecting the small colon in horses and are much more prevalent in ponies and miniature horses. Ventral midline laparotomy under general anaesthesia is the standard of care for this condition when medical management fails to resolve the impaction or when the impaction causes complete intraluminal obstruction and tympany. This case series reports the use of standing flank laparotomy (SFL) in 15 ponies with focal small colon impactions and one large breed horse with an elongated small colon impaction. All cases presented with signs of colic of 1–4 days' duration. The horses were initially vigorously treated with both enteral and parental fluids but failed to pass faeces, with no resolution of abdominal distention or pain. In all cases, a definitive diagnosis was made during SFL and the small colon appeared to be viable. The impaction was resolved by extraluminal massage. In the horse and in one pony, in addition to extraluminal massage, high enema was administered during surgery. Routine perioperative treatment with fluids, analgesics, antimicrobials and wound care was provided. All animals survived to discharge. The time from surgical resolution of the impaction to passing faeces was less than 2 h in all but one case. Median duration of hospitalisation was 2 days and all animals returned to their original use by 2 months. The encouraging results of this case series suggest that SFL is a viable alternative to ventral laparotomy for ponies and horses with either focal SCI or extensive SCI.