Peloso Jg

Use of serial measurements of peritoneal fluid lactate concentration to identify strangulating intestinal lesions in referred horses with signs of colic

OBJECTIVE To determine the value of serial measurements of peritoneal fluid lactate concentration (PFL) for detecting strangulating intestinal lesions (SLs) in referred horses with signs of colic. DESIGN Retrospective cohort study. ANIMALS 94 horses with signs of colic. PROCEDURES Medical records of horses evaluated between September 2006 and February 2010 because of signs of colic were reviewed. All included horses had ≥ 2 peritoneal fluid samples collected, including one at admission and another within 1 to 6 hours after admission. Of the 94 horses, 26 were assigned to the SL group on the basis of findings at surgery or necropsy and 68 were assigned to the nonstrangulating intestinal lesion group because their signs of colic resolved with medical management. Peritoneal fluid lactate concentration was measured by use of a handheld lactate monitor. Data were analyzed by use of univariable and multivariable logistic regression analysis. RESULTS PFL at admission > 4 mmol/L, an increase in PFL over time, and especially an increase in PFL over time in horses with a PFL < 4 mmol/L at admission (OR, 62; sensitivity, 95%; specificity, 77%) were significant predictors of horses with an SL. CONCLUSIONS AND CLINICAL RELEVANCE Serially determined PFL was a strong predictor for differentiating horses with SLs from horses with nonstrangulating intestinal lesions. Given the high OR, sensitivity, and specificity of these tests, serially determined PFL may have potential as a screening test for identifying horses with SLs. Further evaluation of the clinical value of PFL for predicting SLs in a prospective, multicenter study is warranted.

Association of catastrophic biaxial fracture of the proximal sesamoid bones with bony changes of the metacarpophalangeal joint identified by standing magnetic resonance imaging in cadaveric forelimbs of Thoroughbred racehorses

OBJECTIVE To compare bony changes in the metacarpophalangeal joint (MCPJ) of racehorses with (cases) and without (controls) biaxial proximal sesamoid bone (PSB) fracture as determined by 2 grading scales applied to images of cadaveric forelimbs obtained by means of standing MRI (sMRI). DESIGN Case-control study. SAMPLE Forelimbs from 74 Thoroughbred racehorses (21 cases and 53 controls) that were euthanized at a Florida racetrack. PROCEDURES Both forelimbs were harvested from cases and controls. Each forelimb underwent sMRI to obtain images of the MCPJ. Two grading scales were described and used for image evaluation; one assessed the density of the PSBs, and the other assessed the integrity of the subchondral bone (SCB) plate at the distopalmar aspect of the third metacarpal bone (MC3). Logistic regression was used to compare the grades between case and control limbs. RESULTS Biaxial PSB fracture was associated with a total PSB grade (sum of lateral and medial PSB grades) ≥ 5 for the fractured limb, total MC3 SCB grade (sum of lateral and medial MC3 SCB grades) ≥ 5 for the contralateral limb, and the presence of orthopedic disease in the contralateral MC3. CONCLUSIONS AND CLINICAL RELEVANCE For cases with biaxial PSB fracture, the density of the PSBs in the affected limb was greater and the MC3 of the contralateral limb was more likely to have orthopedic disease, compared with those for controls. Further evaluation of sMRI as a screening tool for identification of racehorses at risk of biaxial PSB fracture is warranted.

Comparison of phenylephrine administration and exercise versus phenylephrine administration and a rolling procedure for the correction of nephrosplenic entrapment of the large colon in horses: 88 cases (2004-2010).

OBJECTIVE To compare the outcome of horses with nephrosplenic entrapment of the large colon (NSELC) that were treated nonsurgically by IV administration of phenylephrine and exercise with that of horses treated by IV administration of phenylephrine and a rolling procedure under general anesthesia. DESIGN Retrospective case series. ANIMALS 88 horses with NSELC. PROCEDURES Horses examined between 2004 and 2010 because of acute abdominal pain that had NSELC on the basis of findings on abdominal palpation per rectum, abdominal ultrasonography, or both were included. Medical records were reviewed to obtain information on treatment (IV administration of phenylephrine and exercise vs IV administration of phenylephrine and a rolling procedure) and outcome. RESULTS Overall, 85% (75/88) of horses with NSELC responded to exercise or rolling under general anesthesia. The success rate of rolling under general anesthesia (42/50 [84%]) was significantly higher than the success rate of exercise after IV administration of phenylephrine (24/38 [63.2%]). Resolution of NSELC was achieved by rolling under general anesthesia in 8 of 14 horses that initially failed to resolve with exercise. CONCLUSIONS AND CLINICAL RELEVANCE A rolling procedure performed under general anesthesia had a higher success rate than exercise after IV phenylephrine administration for resolution of NSELC in horses, suggesting that rolling could be considered as the initial medical treatment. The rolling procedure may be labor intensive and should only be attempted in a surgical facility in the event that exploratory laparotomy is required.