A Retrospective Study of the Use of Total Parenteral Nutrition in Dogs and Cats

The records of all dogs and cats receiving total parenteral nutrition (TPN) over a 43-month period were examined retrospectively. Dextrose, amino acids, lipids, electrolytes, and vitamins were administered by central venous catheter according to published nutrient recommendations; 72 dogs and 12 cats were studied, accounting for 380 patient days of TPN. Duration of TPN administration was 1–14 days with a mean of 4.5 days. Most animals required TPN because of gastrointestinal dysfunction, and more than half of them gained weight during TPN administration. Mechanical complications were frequent. Metabolic complications, especially lipid and glucose intolerance, were also commonly seen. Septic complications were the least frequently encountered, but resulted in patient morbidity and may have contributed to mortality. Most animals receiving TPN were returned to enteral nutrition and discharged. For critically ill animals unable to tolerate enteral alimentation, TPN can be supportive therapy in the treatment of the primary disease.     

When, how and why to perform a double ballooning technique for dogs with valvular pulmonic stenosis

Pulmonic valvuloplasty is a well-established method for the treatment of valvular pulmonic stenosis in people and dogs. In dogs, pulmonic valvuloplasty has been restricted to a single balloon; however, the simultaneous use of two balloons is common in pediatric cardiology. The use of two balloons provides an alternative to the use of a single large balloon in small dogs with a pulmonic anulus size that requires a large dilation catheter and large diameter introducer. Moreover, double balloon valvuloplasty permits dilation in large dogs with large pulmonic anulus sizes for which standard dilation catheters are not available. This report outlines the materials required, describes the technique, gives the advantages and disadvantages encountered when performing percutaneous double balloon valvuloplasty and provides some ‘tips’ for a successful outcome.     

The Acute Hemodynamic Effects of Milrinone in Dogs With Severe Idiopathic Myocardial Failure

To examine the effects of acute oral milrinone administration (0.75 mg/kg) on dogs with severe idiopathic myocardial failure and the effect of prolonged milrinone administration on survival time, we measured hemodynamics before and 2 hours after drug administration and recorded survival time and cause of death in 13 dogs with dilated cardiomyopathy. Hemodynamics were measured using a Swan-Ganz catheter and femoral artery puncture along with recording an M-mode echocardiogram. Cardiac index increased from 1.92 +/- 0.54 to 3.06 +/- 0.81 L/min/m2, stroke volume index increased from 11.3 +/- 4.3 to 16.7 +/- 6.3 ml/beat/m2, and pulmonary capillary wedge pressure decreased from 23 +/- 8 to 12 +/- 8 mmHg. A clinically significant increase in heart rate was observed in seven dogs, resulting in a statistically significant increase in heart rate for the group from 174 +/- 34 to 194 +/- 44 beats/minute. Mean arterial blood pressure did not change significantly for the group but did decrease more than 20 mmHg in three dogs, suggesting a predominant primary vasodilating effect of milrinone in these dogs. An increase in contractility appeared to be the predominant reason for the improved hemodynamics in seven dogs. Eight dogs died of causes other than worsening heart failure, including four of eight Doberman pinschers that died suddenly, presumably from an acute tachyarrhythmia. Two dogs that had the greatest increase in an index of contractility are alive more than 2 years after the initiation of milrinone administration.     

Antinociceptive Effects of Oxymorphone-Butorphanol-Acepromazine Combination in Cats

Objective—To determine the antinociceptive effects of oxymorphone, butorphanol, and acepromazine individually and in combination to a noxious visceral stimulus in cats. Study Design—Randomized, blinded controlled study. Animals—Eight healthy mixed-breed cats (four male, four female) weighing 4.4 ± 1.2 kg and aged 1 to 2 years old. Methods—A silastic balloon catheter was inserted per rectum and inflated at various pressures. Physiological parameters (respiratory rate, pulse rate, and blood pressure) were also recorded. Subjects were administered individual and combined intravenous (IV) doses of 0.025, 0.05, 0.10, and 0.20 mg/kg oxymorphone and 0.025, 0.05, 0.10, and 0.20 mg/kg butorphanol. A further study of various ratios of butorphanol and oxymorphone (3:1, 2:1, 1:1, 1:2, and 1:3), at a combined equivalent dose of 0.1 mg/kg, was performed in four cats per dose combination. In a separate study, four cats were administered combined IV doses of 0.05 mg/kg each of oxymorphone and butorphanol or 0.05 mg/kg each of oxymorphone, butorphanol, and acepromazine. Results—Combined doses of 0.05 and 0.10 mg/kg of oxymorphone and butorphanol showed mainly additive with some synergistic antinociceptive interactions and the combined dose of 0.2 mg/kg of each agent demonstrated additional antinociceptive effects, P < .05. Additional studies showed that various ratios of the two agents at a total combined dose of 0.10 mg/kg IV did not produce levels of antinociception that were significantly different from each other, P > .05. Acepromazine (ACE) significantly increased the magnitude of antinociception at 15 minutes when administered in combination with oxymorphone and butorphanol, P < .05. Also, physiological variables were unaffected by these drug combinations. Conclusions—Low doses of oxymorphone and butorphanol in combination can produce greater levels of antinociception than when used individually. ACE, in conjunction with oxymorphone and butorphanol, produced even greater levels of antinociception than the two-opioid drug combination. Clinical Relevance—Oxymorphone, butorphanol, and ACE can be used in combination to produce additive or synergistic effects without adverse effects in cats. These data suggest that ACE and butorphanol at low doses given as preanesthetic medication followed by a mu opioid (eg, oxymorphone) after surgery at low doses may provide an effective method of pain management in the cat.