Predicting maximal lactate steady state from lactate thresholds determined using methods based on an incremental exercise test in beagle dogs: A study using univariate and multivariate approaches.

The reliability of four lactate threshold (LT) methods to estimate the maximal lactate steady state (MLSS), defined as the highest intensity that can be maintained without plasma lactate ([La-]) accumulation over time, was determined in Beagle dogs. Six male Beagle dogs performed a standardized incremental exercise test on a treadmill when plasma lactate ([La-]) measurements were performed. The LTs for predicting MLSS, were determined by visual inspection (LTV), using a bi-segmented linear regression model (LTBI), or using a polynomial function on the [La-]/velocity ratio (LTP) by considering the vertices of the curve and calculating the point that yields the maximal distance from a curve representing [La-] as a function of velocity to the line formed by the two endpoints of the curve (LTDMAX method). The agreement was assessed using Bland-Altman plots and ordinary least products (OLP) regression among the velocities corresponding to the LTs identified using different methods (VLTv, VLTBI, VLTP, and VLTDMAX) and the velocity corresponding to the MLSS (VMLSS). A principal component (PC) analysis approach was performed to detect the degree of co-relatedness among the variables. The mean ± SD [La-] at MLSS was 1.03 ± 0.24 mM. VMLSS had a lower mean bias with VLTv, followed by VLTBI. The VLTDMAX underestimated MLSS. VLTv and VLTBI had the lowest limits of agreement with the VMLSS. The VLTP and VLTDMAX showed relatively high limits of agreement with MLSS. VLTv, VLTBI, and VMLSS had more collinearity and were dominantly aligned with the second component (PC2). VLTv and VLTBI can be used as simple methods to objectively determine aerobic fitness in Beagle dogs.

Comparative study between fasciocutaneous and myocutaneous flaps in the surgical treatment of pressure ulcers of the sacral region.

INTRODUCTION: Decubitus ulcers of the sacral region are common conditions in bedridden patients. Deep lesions (Stages III and IV) often require surgical treatment for closure. Flaps of the region are the first choice for treatment. We present our experience in the treatment of these lesions and compare two different approaches: local fasciocutaneous flap and gluteus maximus myocutaneous flap with V-Y advancement. METHOD: From March 2009 to May 2014, 32 patients underwent closure of sacral pressure ulcers by flaps, 17 of them with rotational local fasciocutaneous flaps and 15 with myocutaneous flaps of the gluteus maximus muscle with V-Y advancement. Evolution regarding complications and rate of success after two months was compared between the groups. RESULTS: Out of the 32 operated patients we obtained resolution of lesions after two months in 23 (71.8%), 10 patients in the fasciocutaneous flap group (58.8%) and 13 cases in the myocutaneous flap group (86.6%). The most common complication was partial dehiscence of sutures in 12 patients (37.5%), 8 patients in the fasciocutaneous flap group (47%) and 4 patients in the myocutaneous flap group (26.6%). The group of patients reconstructed with local fasciocutaneous flaps presented 3 cases with seroma, one with hematoma and 6 with partial cutaneous necrosis; these patients also required more drainage time. CONCLUSIONS: Both the local rotational fasciocutaneous flap and the myocutaneous flap of the gluteus maximus muscle in V-Y flap can be used in the surgical treatment of sacral ulcers. In our experience, a reduced success rate and more complications were found in the local fasciocutaneous reconstructive method.