Repeat Celiotomy-Current Status

Repeat celiotomy can be lifesaving in horses with a surgically treatable postoperative obstruction, although guidelines for its use are lacking, except for uncontrollable postoperative pain. Overdiagnosis of ileus as the cause of postoperative obstruction could delay a second surgery so the disease progresses beyond a manageable level of severity. Although many horses respond favorably to repeat celiotomy, complications can be severe and life threatening, such as incisional infection and adhesions. Repeat celiotomy does not seem to exacerbate postoperative ileus, despite additional surgical manipulation. An important benefit of repeat celiotomy is termination of hopeless cases, thereby reducing cost and suffering.

Comparison of liberal and goal-directed fluid therapy after small intestinal surgery for strangulating lesions in horses

BACKGROUND

There are few guidelines for the appropriate mode of fluid administration during and after colic surgery, and is challenging to reach the right balance while avoiding overhydration. This study aimed to compare goal-directed fluid therapy (GDFT) and 'liberal' fluid regimens (LFRs) in horses undergoing small intestinal surgery.

METHODS

Eighteen horses subjected to small intestinal surgery were matched according to the surgical lesion, type of anastomosis, length of resection, and duration of clinical signs. Horses in the LFR group were administered intravenous (IV) fluids for at least 24 h. In the GDFT group, IV fluids were administered only when considered necessary based on clinical parameters. Postoperative reflux (POR), packed cell volume, total protein, heart rate, venous lactate level, complications, and long-term survival rates were compared.

RESULTS

Three horses in the LFR and one in the GDFT group developed POR. Horses in the GDFT group had a shorter time interval to first oral water intake and shorter hospitalisation time. Postoperative complication rates and survival were not different between groups.

CONCLUSION

Further studies are necessary to set guidelines for the evaluation of hydration status and to plan postoperative fluid administration; however, GDFT may be a valid alternative to liberal fluid therapy after colic surgery.

Postoperative Ileus: Comparative Pathophysiology and Future Therapies

Postoperative ileus (POI), a decrease in gastrointestinal motility after surgery, is an important problem facing human and veterinary patients. 37.5% of horses that develop POI following small intestinal (SI) resection will not survive to discharge. The two major components of POI pathophysiology are a neurogenic phase which is then propagated by an inflammatory phase. Perioperative care has been implicated, namely the use of opioid therapy, inappropriate fluid therapy and electrolyte imbalances. Current therapy for POI variably includes an early return to feeding to induce physiological motility, reducing the inflammatory response with agents such as non-steroidal anti-inflammatory drugs (NSAIDs), and use of prokinetic therapy such as lidocaine. However, optimal management of POI remains controversial. Further understanding of the roles of the gastrointestinal microbiota, intestinal barrier function, the post-surgical inflammatory response, as well as enteric glial cells, a component of the enteric nervous system, in modulating postoperative gastrointestinal motility and the pathogenesis of POI may provide future targets for prevention and/or therapy of POI.

Small Intestine Ultrasound Findings on Horses Following Exploratory Laparotomy, Can We Predict Postoperative Reflux?

Simple Summary

Postoperative reflux is a well-recognized complication after exploratory laparotomy, particularly in horses that present with small intestine pathology. Even though much has been written about the pathophysiology and management of this postsurgical complication, we could not find a study that describes the monitoring of small intestine appearance after laparotomy via transcutaneous abdominal ultrasound. Therefore, the aim of the study was to provide clinical evidence of ultrasound finds in 58 horses over three days post exploratory laparotomy. The results from these exams were compared to the abdominal ultrasounds of 20 horses undergoing general anesthesia for an elective procedure, which were used as a control group. Differences were found between horses with versus without small intestinal pathology. Horses operated on because of large colon pathology had similar ultrasound findings to the control group during the postoperative period. In contrast, horses that were presented with small intestinal pathology had more visible small intestine loops, increased loop diameter, and wall thickness, before and after surgery, particularly those cases that had undergone a resection and anastomosis. A quick abdominal ultrasound in horses, during the postoperative period after colic surgery, was a useful method to identify horses with abnormal small intestinal parameters, both pre- and post-surgery. Further investigation as to whether these parameters can be used to predict postoperative reflux (POR) in a larger population is warranted.

Abstract

Postoperative reflux (POR) is a well-recognized complication after colic surgery in horses, particularly when presenting small intestinal pathology. Even though much has been written about the pathophysiology and management of POR, additional clinical studies are needed to better understand and anticipate this complication. The aim of the study was to provide clinical evidence of ultrasound findings in the postoperative period (three days). The study is based on transcutaneous abdominal ultrasounds of the caudoventral abdomen during the postoperative period (three days), in 58 horses, presented for an exploratory laparotomy, and compared to 20 horses that underwent general anesthesia for an elective surgical procedure. Small intestine (SI) images and videos were analyzed for loop number, loop diameter, wall thickness, motility, and echogenic type of loop contents. Ultrasound findings of horses that had a large colon pathology were similar to those of the control group. Interestingly, horses that presented an SI pathology had significantly thicker SI walls, increased loop diameter, slower motility, and hypoechoic contents, particularly in horses that had undergone small intestinal resection and anastomosis. Although the number of horses that developed POR in our study was too small for statistical analysis, they all had the aforementioned ultrasonographic changes. Abdominal ultrasound, during the postoperative period (three days), was a useful method to identify horses with abnormal small intestinal parameters. Further investigation as to whether these parameters can be used to predict POR in a larger population is warranted.

Is There Still a Place for Lidocaine in the (Postoperative) Management of Colics?

Intravenous lidocaine is widely used to prevent or treat postoperative ileus in horses. Clinical studies that support this approach are flawed and contradicted by others. Also, physical obstruction could be more important in causing postoperative reflux than postoperative ileus in the horse. The antiinflammatory properties of lidocaine and the role of inflammation from intestinal handling in the genesis of postoperative reflux are questionable. Because of cost and questionable efficacy of lidocaine, a well-designed clinical trial is required to support its continued use. However, lidocaine could be given to provide or enhance analgesia in selected cases with postoperative colic.

Has intravenous lidocaine improved the outcome in horses following surgical management of small intestinal lesions in a UK hospital population?

Background

Perioperative lidocaine treatment is commonly used in horses that undergo surgical treatment of colic, to prevent or treat postoperative ileus and reduce the effects of intestinal ischaemia-reperfusion injury. However, its clinical efficacy has not been evaluated in a large population of horses undergoing small intestinal surgery. The aim of the current study was to evaluate whether systemic lidocaine administration reduced the prevalence, volume and duration of postoperative reflux and improved rates of survival following surgical treatment of small intestinal lesions. Data were collected as a part of two prospective studies investigating postoperative survival of surgical colic patients admitted to a UK equine referral hospital during the periods 2004–2006 and 2012–2014. Kaplan-Meier plots of cumulative probability of survival and the log-rank test were used to compare survival between horses that did or did not receive lidocaine. The Wilcoxon rank-sum test was used to compare the total reflux volume and duration of reflux between the groups. A multivariable Cox proportional hazards model was used to identify pre- and intraoperative risk factors for non-survival.

Results

Data from 318 horses were included in the final analysis. The overall prevalence of postoperative reflux was 24.5 %. This was significantly higher (34.8 %) in horses admitted in 2012–2014 compared to the 2004–2006 cohort (16.7). Perioperative lidocaine treatment had no effect on total reflux volume, duration of reflux or rates of postoperative survival nor was it a risk factor associated with altered postoperative survival. Variables identified to be associated with increased risk of postoperative mortality included packed cell volume on admission (hazard ratio [HR] 1.03 95 %, 95 % confidence interval [CI] 1.004–1.06, p = 0.024), heart rate on admission (HR 1.014, 95 % CI 1.004–1.024, p =0.008) and duration of surgery (HR 1.007, 95 % CI 1.002–1.01, p = 0.008).

Conclusions

Lidocaine therapy had no effect on the prevalence of postoperative reflux, total reflux volume and duration of reflux nor did it have any effect on postoperative survival in horses undergoing surgical management of small intestinal disease for treatment of colic. There is a need for a well-designed multicentre, prospective randomised controlled trial to fully investigate the efficacy of lidocaine across different hospital populations.

Electronic supplementary material

The online version of this article (doi:10.1186/s12917-016-0784-7) contains supplementary material, which is available to authorized users.

Clinical features and management of equine post operative ileus (POI): Survey of Diplomates of the American Colleges of Veterinary Internal Medicine (ACVIM), Veterinary Surgeons (ACVS) and Veterinary Emergency and Critical Care (ACVECC)

REASONS FOR PERFORMING STUDY

A recent survey of European Colleges (European College of Equine Internal Medicine [ECEIM] and European College of Veterinary Surgeons [ECVS]) revealed the different strategies implemented by, and some of the challenges facing, European clinicians presented with cases of post operative ileus (POI). It was concluded that further comparative analysis of opinions, canvassed from additional colleges of equine veterinary specialism worldwide, would provide valuable additional insight into current POI knowledge on a more global scale.

OBJECTIVES

To report and compare the current strategies favoured by American veterinary specialists when managing POI in horses that underwent emergency colic surgery.

STUDY DESIGN

Cross-sectional survey.

METHODS

Electronic invitations were sent to 814 Large Animal specialists, including 3 colleges: the American College of Veterinary Internal Medicine (ACVIM), American College of Veterinary Surgeons (ACVS) and the American College of Veterinary Emergency and Critical Care (ACVECC).

RESULTS

The response rate was 14% (115/814). The majority of respondents (68%) reported an estimated prevalence range of POI of 0-20%. The presence of reflux on nasogastric intubation was the main criterion used to define POI. A lesion involving the small intestine was considered the main risk factor for POI. Anti-inflammatory drugs, intravenous (i.v.) fluids and antimicrobial drugs were the primary strategies used when managing POI. Flunixin meglumine and i.v. lidocaine were the drugs most commonly used in the treatment of horses with POI. Supplementary management strategies targeted mainly the prevention of post operative adhesions, infection and inflammation.

CONCLUSIONS

There is a lack of consensus on the clinical definition of POI. Prospective and objective clinical assessment of the effectiveness of the different strategies contained within this and the European survey is necessary in order to identify a standardised approach to the management of equine POI.

Prevention of post operative complications following surgical treatment of equine colic: Current evidence

Changes in management of the surgical colic patient over the last 30 years have resulted in considerable improvement in post operative survival rates. However, post operative complications remain common and these impact negatively on horse welfare, probability of survival, return to previous use and the costs of treatment. Multiple studies have investigated risk factors for post operative complications following surgical management of colic and interventions that might be effective in reducing the likelihood of these occurring. The findings from these studies are frequently contradictory and the evidence for many interventions is lacking or inconclusive. This review discusses the current available evidence and identifies areas where further studies are necessary and factors that should be taken into consideration in study design.

Clinical features and management of equine post operative ileus: Survey of diplomates of the European Colleges of Equine Internal Medicine (ECEIM) and Veterinary Surgeons (ECVS)

REASONS FOR PERFORMING STUDY

There is a need for an improved understanding of equine post operative ileus (POI), in terms of both clinical definition and optimal management. Although the pharmacological strategies that are used to treat POI continue to evolve, little is known about the supplementary strategies used to prevent and manage this condition.

OBJECTIVES

To report the current strategies used to diagnose, prevent and manage POI following emergency abdominal surgeries.

STUDY DESIGN

Cross-sectional survey.

METHODS

An electronic survey invitation was sent by email to 306 European college diplomates (European Colleges of Equine Internal Medicine, ECEIM n = 120, and Veterinary Surgeons, ECVS n = 186).

RESULTS

The response rate was 33% (100 of 306). The median reported estimated incidence of POI was 10-20%. The presence of reflux on nasogastric intubation was the main criterion used to define POI. Lesions involving the small intestine were thought to be the leading risk factors for developing POI. Anti-inflammatory drugs, antimicrobial drugs and i.v. fluids were the primary preventative strategies when managing cases at high risk for POI. Flunixin meglumine and lidocaine were the drugs most commonly used to treat horses with POI. Supplementary preventative and treatment strategies for POI included control of endotoxaemia, fluid therapy, early ambulation and judicious timing of post operative feeding.

CONCLUSIONS

Appreciation of the potential risk factors associated with the development of POI appeared to have an impact on the choice of management strategies that are implemented. The majority of ECEIM and ECVS Diplomates in the survey used flunixin meglumine and lidocaine, often in combination, to treat horses with POI, which is likely to reflect the contributory role of inflammation in its pathophysiology. Various supplementary strategies were used to prevent and manage POI risk factors intraoperatively and post operatively.

Long-term survival in horses with strangulating obstruction of the small intestine managed without resection

REASONS FOR PERFORMING STUDY

Although many studies have described results after small intestinal resection and anastomosis in horses, few have described the outcome in horses with strangulating lesions managed without resection.

OBJECTIVES

To examine short- and long-term recoveries in horses with strangulated small intestine that was judged to be viable during surgery and not resected.

STUDY DESIGN

Retrospective analysis of case records.

METHODS

Data were reviewed from all cases (35 horses) with colic caused by small intestinal strangulation that underwent surgery between 1996 and 2011 at 2 university hospitals and that were managed without resection by 2 surgeons who used a clinical grading system to assess intestinal viability. Kaplan-Meier analyses were used to examine long-term survival.

RESULTS

Survival to discharge from the hospital was 100%, and post operative complications developed in 11 horses (31%). Three horses (8.6%) required repeat coeliotomy because of persistent pain with or without reflux, and they responded favourably to decompression of distended intestine. Ten horses died after discharge, and 12 were still alive at follow-up from 20 to 192 months after surgery. Information was available on 13 horses after discharge, but these were eventually lost to follow-up. Kaplan-Meier analyses yielded a median survival probability of 120 months.

CONCLUSIONS

A subjective method of assessing small intestinal viability in strangulated small intestine in horses, as used in this study, could reduce the need for resection and anastomosis, with the associated complications and costs. Also, the favourable post operative course in these horses provides strong evidence that early referral could avoid the need for resection and improve survival. The numbers of horses with the most severe changes that were not resected were too small to allow a conclusion that such segments should be left in place, and additional criteria might be needed to guide that decision in such cases.