Anesthetic management in feline renal transplantation

Objective To document perioperative and anesthetic management of 30 feline renal transplant recipients (1996–1998). Study design Retrospective clinical study. Animals Thirty adult cats in end‐stage renal failure that underwent heterotopic renal transplantation. Materials and methods The medical records were reviewed from 30 feline heterotopic renal transplant recipients. Cases were included only if they had been treated for hypertension using a beta‐adrenergic antagonist, a calcium channel blocker or hemodialysis. Data regarding signalment, preoperative management, surgical technique, type and doses of anesthetics administered, perioperative hemodynamics and intra‐ and postoperative complications, postoperative analgesia, morbidity and early mortality were recorded. Data were expressed as mean ± SD. Results Preanesthetic medication included a combination of an anticholinergic and an opioid (oxymorphone). Anesthesia induction was performed mostly with isoflurane and oxygen delivered by mask. Anesthesia maintenance was primarily achieved with isoflurane in 100% oxygen. Nitrous oxide was often used as part of the anesthetic technique. The mean duration of anesthesia was 4.6 hours ± 27 minutes. The mean renal allograft ischemic time was 60 minutes. During the anesthetic period, the majority of the recipient cats received either fresh whole blood (FWB) (N = 25, 83%), cross‐matched packed red blood cells (PRBC) (N = 3, 10%) or fresh frozen plasma (FFP) (N = 2, 7%) combined with a balanced electrolyte solution. Blood products administered averaged 63 ± 34 mL and crystalloid 94 ± 62 mL. The most common treated intraoperative complications were hypotension (N = 14, 47%), hypothermia (N = 13, 43%), metabolic acidosis (N = 11, 37%), hypocalcemia (N = 5, 17%), hypoglycemia (N = 4, 13%), hypertension (N = 2, 7%), bradycardia (N = 1, 3%), and ventricular premature contractions (N = 1, 3%). All cats received opioid analgesics postoperatively. Complications observed in the first 24 hours postoperatively were hypertension (N = 20, 67%), hematuria (N = 14, 47%), electrolyte disturbances (N = 9, 30%), temperature imbalances (N = 5, 17%), decreased PCV requiring blood transfusion (N = 5, 17%), decreased perfusion of a foot associated with external iliac anastomosis technique (N = 5, 17%), seizures associated with hypertension (N = 3, 10%), uroabdomen (N = 2, 7%), acute graft rejection (N = 1, 3%) and, corneal ulceration (N = 1, 3%). Survival rates in the perioperative period were 100, 96.7, and 93.4% intraoperatively, at 24 hours, and 7 days following surgery. Conclusion Successful anesthesia can be performed in critically ill renal transplant recipients. However, for optimal graft function and patient survival, normothermia, normovolemia, normotension, and normal acid–base and electrolyte balance should be carefully maintained. Successful anesthetic management requires understanding of the pathophysiology of end‐stage renal disease and the maintenance of homeostasis during the different stages of the perioperative period.     

Nitrogen efficiency in grain sorghum

Grain sorghum, Sorghum bicolor (1.) Moench has not been fully evaluated for its variability in nitrogen efficiency. A 2‐year study using 12 hybrids was conducted and nitrogen efficiency was calculated as: 1. total dry matter (DM) per unit N uptake (NE₁), 2. total grain yield per unit N uptake (NE₂), and 3. the product of NE₂ and the grain N:stover N ratio (NE₃). NE₁ values increased with plant age and were significantly different among hybrids at all stages of growth. A 20% difference in NE₁ was found between the least and most efficient hybrids at maturity. A significant hybrid x year interaction showed that the environment strongly influenced hybrid ranking. Hybrids which ranked high in one year often did poorly the other year and visa versa for NE₁, NE₂, or NE₃. Each N efficiency criterion ranked the hybrids differently, although NE₁ and NE₂ appeared to be the most closely related. Hybrids generally maintained satisfactory values for NE₃ if one parent (either male or female) had a high NE₃ value in hybrid combination. Differences were more dramatic for partitioning of N between grain and stover than for NE values among hybrids. Due to environmental influences, it appears that at least 3 or more years of data may be needed in order to establish consistent trends for N efficiency in grain sorghum.     

Evaluation of increased fiber,decreased amino acids,or decreased electrolyte balance as dietary approaches to slow finishing pig growth rates

In swine production, pig movement restrictions or packing plant closures may create the need to slow growth rates of finishing pigs to ensure they remain at a marketable body weight when packing plant access is restored. Although dietary formulations can be successful at slowing pig growth, precision is needed regarding how to best formulate diets to achieve growth rate reductions. Thus, the objective was to evaluate three dietary experimental approaches aimed at slowing growth rates in finishing pigs. These approaches consisted of either increasing neutral detergent fiber (NDF), reducing essential amino acids, or reducing the dietary electrolyte balance through the addition of acidogenic salts. A total of 94 mixed-sex pigs (72.4 ± 11.2 kg BW) across two replicates were individually penned and assigned to 1 of 8 dietary treatments (n = 11–12 pigs/treatment): 1) Control diet representative of a typical corn–soybean meal-based finisher diet (CON); 2) diet containing 15% NDF from soybean hulls (15% NDF); 3) diet containing 20% NDF from soybean hulls (20% NDF); 4) diet containing 25% NDF from soybean hulls (25% NDF); 5) diet formulated as per CON but with 50% of the soybean meal replaced with corn (89% Corn); 6) diet containing 97% corn and no soybean meal or synthetic amino acids (97% Corn); 7) diet containing 2% anhydrous calcium chloride (2% CaCl₂); and 8) diet containing 4% anhydrous calcium chloride (4% CaCl₂). Over 28 d, pig body weights and performance were recorded weekly. At d 28, all pigs were ultrasound scanned and switched to the CON diet to evaluate compensatory gain from d 28 to 35. Overall, increased NDF did not impact any growth performance parameter (P > 0.05). Amino acid restriction reduced average daily gain (ADG), average daily feed intake (ADFI), and gain:feed (G:F) linearly (linear P < 0.001). Similarly, ADG, ADFI, and G:F were linearly reduced with increased CaCl₂ inclusion (linear P < 0.001). ADG differed during the compensatory gain period (P < 0.001), with 4% CaCl₂-fed pigs having a 47% increase in ADG compared with CON-fed pigs. Conversely, 15% and 25% NDF-fed pigs had reduced ADG compared with CON-fed pigs during the compensatory gain period. Gain efficiency differed from day 28 to 35 (P < 0.001), with 4% CaCl₂-fed pigs having a 36% increase in G:F compared with CON-fed pigs. Altogether, these data demonstrate that both amino acid restriction and CaCl₂ inclusion are effective at slowing pig growth, albeit at greater inclusion rates.