Search Results

You are looking at 1 - 7 of 7 items for

  • Author or Editor: Marlee Richter x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract

Objective—To assess the influence of preanesthetic administration of acetylpromazine or morphine and fluids on urine production, arginine vasopressin (AVP; previously known as antidiuretic hormone) concentrations, mean arterial blood pressure (MAP), plasma osmolality (Osm), PCV, and concentration of total solids (TS) during anesthesia and surgery in dogs.

Animals—19 adult dogs.

Procedure—Concentration of AVP, indirect MAP, Osm, PCV, and concentration of TS were measured at 5 time points (before administration of acetylpromazine or morphine, after administration of those drugs, after induction of anesthesia, 1 hour after the start of surgery, and 2 hours after the start of surgery). Urine output and end-tidal halothane concentrations were measured 1 and 2 hours after the start of surgery. All dogs were administered lactated Ringer's solution (20 ml/kg of body weight/h, IV) during surgery.

Results—Compared with values for acetylpromazine, preoperative administration of morphine resulted in significantly lower urine output during the surgical period. Groups did not differ significantly for AVP concentration, Osm, MAP, and end-tidal halothane concentration; however, PCV and concentration of TS decreased over time in both groups and were lower in dogs given acetylpromazine.

Conclusions and Clinical Relevance—Preanesthetic administration of morphine resulted in significantly lower urine output, compared with values after administration of acetylpromazine, which cannot be explained by differences in AVP concentration or MAP. When urine output is used as a guide for determining rate for IV administration of fluids in the perioperative period, the type of preanesthetic agent used must be considered.(Am J Vet Res 2001;62:1922–1927)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate effects of anesthesia, surgery, and intravenous administration of fluids on plasma concentrations of antidiuretic hormone (ADH), concentration of total solids (TS), PCV, arterial blood pressure (BP), plasma osmolality, and urine output in healthy dogs.

Animals—22 healthy Beagles.

Procedure—11 dogs did not receive fluids, and 11 received 20 ml of lactated Ringer's solution/kg of body weight/h. Plasma ADH adn TS concentrations, PCV, osmolality, and arterial BP were measured before anesthesia (T0) and after administration of preanesthetic agents (T1), induction of anesthesia (T2), and 1 and 2 hours of surgery (T3 and T4, respectively). Urine output was measured at T3 and T4.

Results—ADH concentrations increased at T1, T3, and T4, compared with concentrations at T0. Concentration of TS and PCV decreased at all times after administration of preanesthetic drugs. Plasma ADH concentration was less at T3 in dogs that received fluids, compared with those that did not. Blood pressure did not differ between groups, and osmolality did not increase > 1% from T0 value at any time. At T4, rate of urine production was less in dogs that did not receive fluids, compared with those that did.

Conclusions and Clinical Relevance—Plasma ADH concentration increased and PCV and TS concentration decreased in response to anesthesia and surgery. Intravenous administration of fluids resulted in increased urine output but had no effect on ADH concentration or arterial BP. The causes and effects of increased plasma ADH concentrations may affect efficacious administration of fluids during the perioperative period in dogs. (Am J Vet Res 2000;61: 1273–1276)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To determine whether autologous jugular veins provide functional grafts with high 30-day patency rates in an experimental model of systemic-to-pulmonary shunting performed with a modified Blalock-Taussig procedure.

Animals—15 healthy Beagles.

Procedure—A segment of the left jugular vein was implanted between the left subclavian and pulmonary arteries. Echocardiograms were obtained prior to surgery, at day 4 to 7, and at day 30 after surgery. Selective angiograms were performed immediately after surgery and on day 30. Oximetric shunt calculations were made via terminal angiography prior to euthanasia. Gross and histologic evaluations of the grafts were conducted.

Results—Grafts were patent in 12 of 15 dogs 30 days after surgery as assessed via auscultation, color Doppler ultrasonography, angiography, and histologic examination. Echocardiographic analysis revealed compensatory eccentric left ventricular hypertrophy. Mean pulmonary-to-systemic flow ratio was 1.5:1. Histologic evidence of endothelialization of the anastomotic sites and vein graft arterialization was detectable at 30 days.

Conclusions and Clinical Relevance—Autologous jugular vein grafts were effectively used to create a systemic-to-pulmonary shunt by use of a modified Blalock-Taussig procedure. High patency, ready accessibility, low cost, and theoretical adaptative remodeling during patient growth make autologous jugular vein grafts a valuable alternative to synthetic materials.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate the effects of nephrotomy on renal function in clinically normal cats.

Animals—20 specific-pathogen-free, 9- to 11-month old female mixed-breed cats.

Procedure—Serum chemistry analyses, CBC determinations, urinalyses, microbiologic urine cultures, renal ultrasonography, abdominal radiography, and single-kidney and total glomerular filtration rate (GFR) determinations by use of renal scintigraphy and measurements of plasma disappearance of technetium 99m-diethylenetriaminepentaacetic acid were performed before surgery and at 3, 12, 26, 52, and 78 weeks after surgery in 10 cats that underwent unilateral nephrotomy and in 10 control cats that underwent a sham surgical procedure.

Results—Two cats (1 from each group) did not complete the study, and their data were eliminated from analyses. Unilateral nephrotomy resulted in a 10% to 20% reduction in mean single-kidney GFR, compared with that of nephrotomy contralateral control kidneys. However, mean total GFR in nephrotomy-group cats was not significantly different from that of shamgroup cats. Over the 78 weeks of study, mean total GFR declined 34% and 40% in nephrotomy- and sham-group cats, respectively. Adverse events associated with nephrotomy included persistent microscopic hematuria, renal pelvis hyperechogenicity with distant shadowing on ultrasonographic evaluation, dilatation of renal pelves, and hydronephrosis.

Conclusions and Clinical Relevance—Nephrotomy in normal functioning feline kidneys results in a modest relative reduction in renal function, compared with contralateral kidney controls, but has minimal effect on total GFR when compared with sham-operated control cats. However, any detrimental effects of nephrotomy may be magnified in cats with diseased kidneys, which may have little or no capacity for repair or compensation. (Am J Vet Res 2005;66:1400–1407)

Full access
in American Journal of Veterinary Research

Abstract

Objective

To use ground reaction forces and related impulses as an objective measurement of limb function in the comparison of 1 extracapsular and 1 intracapsular surgical technique for repair of cranial cruciate ligament rupture in dogs.

Animals

18 healthy dogs.

Design

All dogs underwent force-plate analysis of gait prior to transection of the left cranial cruciate ligament. The dogs were randomly allotted to 3 groups. The ligamentous instability was corrected, using a modified retinacular imbrication technique (MRIT) in 1 group and an under-and-over technique in another group. No attempt was made to correct the ligamentous instability in a control group. Clinical grading of lameness and force-plate analysis of gait were performed at 4, 8, 12, 16, and 20 weeks after surgery.

Procedure

Peak vertical force and vertical, braking, and propulsion impulses were recorded for each limb at each time. The degree of clinical lameness was graded at each time.

Results

Left hind limb peak vertical forces and vertical impulses were significantly decreased at all times after surgery in the control and under-and-over technique group, compared with values before surgery. Dogs of the MRIT group had improved by 20 weeks, with no significant differences between left hind limb peak vertical forces or vertical impulses recorded before surgery and at 20 weeks.

Conclusion

Peak vertical forces and vertical impulses in dogs undergoing MRIT repair after experimentally created cranial cruciate ligament rupture are not significantly different when values recorded for the operated limb at 20 weeks after surgery are compared with those recorded prior to surgery.(Am J Vet Res 1996;57:389-393)

Free access
in American Journal of Veterinary Research

SUMMARY

Butorphanol (0.025, 0.05, 0.1, 0.2, 0.4, and 0.8 mg/kg of body weight, and placebo) was given sc to 8 healthy unmedicated dogs to determine its efficacy for visceral analgesia, using a colonic balloon for minimal threshold nociceptor stimulation. Degree of sedation; systolic, diastolic, and mean arterial pressure; and pulse rate were recorded. The highest 3 dosages, 0.2, 0.4, and 0.8 mg/kg, were found to be most effective, with 0.8 mg/kg the only dosage that was significantly different from control responses at the 45-minute interval. Duration of analgesia ranged from 23 to 53 minutes for all 6 dosages and dosing durations were not significantly different from one another. Blood pressures did not change, but pulse rate was significantly decreased by 0.8 mg of butorphanol/kg. We concluded that butorphanol is an effective visceral analgesic of relatively short duration in the dog.

Free access
in American Journal of Veterinary Research

Summary

This study was designed to test analgesia, duration, and cardiovascular changes induced by meperidine (mep) and oxymorphone (oxy) following methoxyflurane (mof) and halothane (hal) anesthesia. Eight healthy dogs were given atropine and acepromazine, and anesthesia was induced with thiamylal and maintained with 1.5 minimal alveolar concentration of mof or hal for 1 hour during controlled ventilation. Eight treatments were given with each anesthetic: 3 with mep (0.5, 1.0, and 2.0 mg/kg, iv), 3 with oxymorphone (oxy; 0.05, 0.1, and 0.2 mg/kg, iv), and 2 placebos with sterile water. Test drugs were given at the end of anesthesia when early signs of recovery were evident. Minimal threshold stimulus/response nociception was assessed by use of an inflatable soft plastic colonic balloon. Blood pressures and pulse rate were measured with a noninvasive monitor. Meperidine and oxy were found to be effective analgesics and could be reversed with naloxone. Intravenous administration of 2.0 mg of mep/kg provided analgesia for 36 ± 6 minutes and 39 ± 15 minutes after mof and hal, respectively. In contrast, oxy was effective at all 3 doses with effects of iv administration of 0.2 mg of oxy/kg lasting 154 ± 13 minutes and 152 ± 12 minutes, after mof and hal, respectively. Analgesia could not be demonstrated after anesthesia for acepromazine, mof, or hal. Blood pressure was not changed by either anesthetic nor was it influenced by mep or oxy. Pulse rate was significantly depressed by the higher doses of oxy following hal, but was not changed by mep following either anesthetic. This study demonstrated the longer duration of analgesia of oxy. In addition, we could not find that analgesia was provided by either mof or hal following recovery from anesthesia.

Free access
in American Journal of Veterinary Research