Intravenous Lidocaine and Small‐Intestinal Size, Abdominal Fluid, and Outcome after Colic Surgery in Horses

Abstract

Twenty-eight horses with the diagnosis of an intestinal disorder requiring surgical intervention were randomly assigned to lidocaine (n ϭ 13) or saline (control, n ϭ 15) treatment groups. After induction of anesthesia, treated horses received a loading dose of 2% lidocaine (0.65 mg/kg) intravenously, followed by a continuous rate of infusion of 1% lidocaine (0.025 mg/kg/min) until the discontinuation of anesthesia. Upon recovery from anesthesia, a 2nd loading dose of 2% lidocaine (1.3 mg/kg) was administered, followed by an infusion of 1% lidocaine (0.05 mg/kg/min) for 24 hours postoperatively. The control group received equivalent volumes of saline. Lidocaine-treated horses had significantly better minimum jejunal cross-sectional area scores (P ϭ .011), minimum jejunal diameter scores (P ϭ .002), and intestinal ultrasound index (IUI) (P ϭ .007). Peritoneal fluid was detected by percutaneous ultrasound examination in 8 of the 15 control animals but in none of the treated animals (P ϭ .003). Failure to obtain fluid via abdominocentesis was significantly more frequent for lidocaine-treated horses (P ϭ .025). No significant differences between the groups were found in the presence of gastrointestinal sounds, time to passage of 1st feces, number of defecations in the 1st 24 hours, presence of gastric reflux, duodenal or jejunal wall thickness, maximum duodenal or jejunal diameter or crosssectional area, minimum duodenal diameter or cross-sectional area, duodenal and jejunal intraluminal echogenicity, small-intestinal contractions per minute, rate of complications, or outcome. On the basis of this study, lidocaine infusion may have some desirable effects on jejunal distension and peritoneal fluid accumulation and was well tolerated perioperatively in horses with colic. The low incidence of small-intestinal lesions and gastric reflux in the study makes it difficult to assess the use of lidocaine in the prevention of postoperative ileus (POI).

Serum concentrations of lidocaine and its metabolites after prolonged infusion in healthy horses

“…The signs of lidocaine toxicity reported in the horse include alteration in visual function, rapid eye blinking, anxiety, mild sedation, ataxia and collapse. (Brianceau et al 2002;Malone et al 2006;Meyer et al 2001) Equine colic patients at the investigator's clinic (MDSEMC) that were receiving prolonged lidocaine infusions have been observed to develop ataxia, muscle tremors and altered mentation, raising concern that toxic levels may have been reached despite the use of the recommended dosage regimen. The target steady state concentration for the treatment of ileus in the horse is 980ng/ml (1000-2000ng/ml range), (Malone et al 1998) and the serum lidocaine concentrations resulting in adverse side effects have been reported to be >1850ng/ml.…”

“…Milligan ( Brianceau et al 2002) Limitations of this study included the lack of gastric reflux in both the treatment and control groups which made it impossible to assess the effect of lidocaine on that particular variable. Furthermore a trend towards a reduction in the time to first defecation was noted in the treatment group, so…”

“…(Malone et al 1998) The reported concentration of lidocaine during short term CRI in horses is very variable even when a similar dosage regimen is used, and in some cases the concentration exceeds the concentrations reported as toxic. (Brianceau et al 2002;Doherty and Frazier 1998;Dzikiti et al 2003;Feary et al 2005;Robertson et al 2005) Due to the lack of pharmacokinetic data of prolonged infusions in horses the following study was designed to report the serum concentrations of Eight mature (mean 9 years, range: 4-11 years old) Standardbred horses were used for the study. There were 5 mares and 3 geldings in the study group.…”

Continuous intravenous lidocaine infusion during isoflurane anaesthesia in horses undergoing surgical procedures

“…Although there is a relevant potential for more ataxia in the recovery, the benefits of lidocaine to significantly reduce the requirement for volatile agent under general anaesthesia has been well documented and meets medical, economical and safety issues. Several other properties have been mentioned for systemic administration of lidocaine, like cellular and biochemical effects on intestinal smooth muscle, blockade of inhibitory spinal and peritoneal sympathetic reflexes, inhibition of central hyperalgesia, anti-inflammatory and antiendotoxic actions (Brianceau et al 2002, Doherty und Seddighi 2010, Malone et al 2006, Peiro et al 2010, Robertson et al 2005, Van Hoogmoed 2003 suggesting other interesting benefits for lidocaine administration.…”

Intravenous lidocaine infusion in balanced anaesthesia for abdominal surgery: update and clinical experiences

“…Sowohl beim Menschen (Groudine et al 1998;Rimbäck et al 1990) als auch beim Pferd (Malone et al 1999;Nieto et al 2000;Brianceau et al 2002;Van Hoogmoed 2003) (Brianceau et al 2002;McCafferty et al 1994) und vermag darüber hinaus Gewebe gegen Ischämie und Reperfusionsschäden zu schützen (Schaub et al 1977;Hatori et al 1991;Wendland et al 1993;Lee et al 1998;Ebel et al 2001). Aus diesen Gründen wird die Lidokain-Infusion bei Kolikpatienten häufig in der frühen postoperativen Phase fortgesetzt.…”