We use high frequency ultrasound to assess the effect of laser cyclophotocoagulation (CPC) on blood flow in the anterior segment of the eye. We show that laser CPC treatment applied to the rabbit eye provides a unique way to interrupt blood flow in the ciliary body, thus serving as a new method for evaluating clutter rejection performance in the microcirculation with and without an ultrasound contrast agent. We apply a recently developed eigendecomposition-based clutter rejection filter with modifications to deal with high blood-to-clutter ratio's (BCR) encountered at high frequencies, particularly with ultrasound contrast agents. In vivo results are presented to illustrate treatment effects, clutter rejection, and contrast agent enhancement.
A group of dairy goats underwent cervical laminoplasty procedures as part of a biomechanics project. Although most animals had minimal incisional complications, several developed excoriations exacerbated by scratching at the incision site 6 to 8 weeks after the surgery. Local and systemic treatment was instituted as indicated. Bandages were inadequate to protect the neck from self-trauma, and the potential existed for serious injury to or infection of the old surgical site. We designed and made custom padded jackets for these animals. Treatment continued. While allowing the animals to exercise their scratching behavior, the jackets protected the traumatized area until healing was complete and the pruritus resolved. This jacket or modifications of it may be useful in other goat, sheep, or calf projects in which protection of the neck, shoulders, and thorax is needed.
A group of 30 older beagle dogs was acquired for aging studies. The dogs were initially housed in kennel runs equipped with elevated benches, but it became apparent that some of the oldest animals had difficulties jumping down from them. To improve animal safety and comfort, practical dog beds were made out of the ends of clean high-density polyethylene barrels. Synthetic fleece bed liners were used for dogs that did not chew them or remove them from the beds. Nine of the beagles regularly were observed to use the beds. We also have found that this easily fashioned dog bed is a useful kennel resting place option for puppies and other small dogs.
Newborn plasma concentrations of maternally administered bupivacaine are often measured, but it is unclear how well they reflect tissue concentrations. Bupivacaine (0.25%) was administered epidurally (0.12 ml/kg) 10 min prior to labor induction in 6 term-pregnant guinea pigs. Plasma, brain, heart and liver samples were obtained for bupivacaine analysis from newborns (n = 22) after spontaneous delivery. Liver bupivacaine concentrations were 2–3 times greater than those in the plasma, brain, and heart. A similar pattern of tissue concentrations was seen in a smaller number of newborns delivered by cesarean section. Liver bupivacaine concentration decreased with drug-delivery interval in littermates, while heart and brain concentrations showed no relationship with drug-delivery interval. Blood gases of newborns reflected acidosis, which may have influenced tissue drug concentrations. Under conditions of the study, bupivacaine concentrations in heart and brain, potential sites of bupivacaine action, were lower than those observed in a peripheral blood sample.
The pregnant guinea pig may be a useful model for the study of drug effects in the newborn. A reliable technique for epidural catheterization in the guinea pig was developed to allow use of this model to evaluate the effects of epidural labor analgesics on neonates. Catheters were implanted in two open pilot animals and 19 time-dated pregnant animals on days 59 to 62 of gestation. After establishing a surgical plane of isoflurane-induced anesthesia, an incision was made over the dorsal lumbar part of the spine. The L3-4 intervertebral space was exposed to allow introduction of a caudally directed 27-gauge catheter into the epidural space. The catheter was capped and implanted subcutaneously, then the animal was allowed to recover from anesthesia. Catheter placement was evaluated, using a bupivacaine test dose in 17 animals and postmortem histologic examination in 20 animals. One animal died immediately after surgery. Epidural placement was confirmed histologically in 15 of 20 animals. Failed catheters were either subdural, with one catheter found to be penetrating the spinal cord (intraspinal), or intramuscular. Response to epidurally administered bupivacaine was variable but was typically characterized by normal alertness and ability to use the forelimbs; depression of the panniculus reflex in the dorsal lumbar region; and hind limb motor impairment, with ataxia, loss of the placing reflex, and a tendency to drag the hind limbs. Subdural placement was associated with CNS depression, recumbency, shallow breathing, and sensory block ascending to the level of the ears.(ABSTRACT TRUNCATED AT 250 WORDS)
Spontaneous vitamin C deficiency, or scurvy, was recognized in juvenile rhesus monkeys maintained in a research center as a result of being fed a commercial diet for 2 to 3 months with low levels of vitamin C. Most severely affected animals (13) were radiographed repeatedly up to day 300 following detection of the disease. Early radiographic changes consisted of widened, lucent metaphyses with lateral flaring and radiopaque metaphyseal lines at the junction of the metaphyses and physes. Physeal slippage was noted commonly. Following institution of vitamin C therapy, calcification of subperiosteal hemorrhage occurred in the metaphyseal regions. Metaphyses and physes returned to normal radiographic appearance within 15 to 30 days. Initially, the ubperiosteal hemorrhage progressed and a longer time was required for resolution of the calcified hematomas. The macaques improved clinically and were released from the hospital when fractures were stable at 4–5 weeks after admission. Of the 13 macaques studied, all but one returned as normal members of the colony.
Young rhesus macaques housed in outdoor corn cribs and fed a commercially prepared primate diet became weak, depressed, were reluctant to move, and expressed locomotor abnormalities. Thirteen severely affected animals were hospitalized for evaluation. Physical examination disclosed swellings and instabilities involving the ends of long bones. Radiography confirmed physeal fractures in 11 of 13 animals. Affected bones included the distal femur, proximal humerus, distal tibia/fibula, and distal radius/ulna. Other, less obvious changes were noted on radiographs. Anemia was a consistent finding. Ascorbic acid deficiency was suspected and therapy was initiated that consisted of vitamin supplements, diet change, cage rest, and support bandages. Feed samples were submitted to a laboratory for analysis and were confirmed deficient in vitamin C. Follow-up radiographs showed large calcifying subperiosteal hematomas in epiphyseometaphyseal regions, consistent with a diagnosis of scurvy. Twelve of 13 animals recovered clinically. Subsequent radiographs documented improvement of initially severe angular deformities associated with displaced fractures.
A syndrome presenting as gross abdominal distension and diagnosed as acquired megacolon was observed in five adult female long-tailed macaques. Gastrointestinal signs included diarrhea, mucus in the stool, anorexia, and failure to pass stool, with repeated episodes of extreme abdominal distension and accumulation of gas and feces in greatly enlarged colons. Medical management was unsuccessful. A partial colectomy with a standard end-to-end colonic anastomosis was performed to remove the section of distended colon in each animal. Histologically, affected colons had degeneration and fibrosis, primarily in the longitudinal layer of the lamina muscularis. Hemograms, serum chemistries, and histopathologic features were not diagnostic of a specific etiology for megacolon. Four of five animals had undergone at least one obstetrical surgery. Two of these had the first episode of colonic distension within 3 days postoperatively. Intra-abdominal adhesions were noted during exploratory surgery in all animals. Three of five had colonic volvulus observed during colectomy. Recovery postcolectomy was uneventful and animals remained free of clinical signs of megacolon.
Annals of the New York Academy of SciencesVolume 508, Issue 1 p. 523-526 Uptake and Elimination of Isoflurane in Rabbit Tissue Studied with 19F NMR Spectroscopya A. M. WYRWICZ, A. M. WYRWICZ Department of Chemistry, University of Illinois at Chicago, Chicago; Illinois 60680Search for more papers by this authorC. B. CONBOY, C. B. CONBOY Department of Chemistry, University of Illinois at Chicago, Chicago; Illinois 60680Search for more papers by this authorP. H. EISELE, P. H. EISELE Animal Resources Service, School of Veterinary Medicine, University of California, Davis, California 95616Search for more papers by this author A. M. WYRWICZ, A. M. WYRWICZ Department of Chemistry, University of Illinois at Chicago, Chicago; Illinois 60680Search for more papers by this authorC. B. CONBOY, C. B. CONBOY Department of Chemistry, University of Illinois at Chicago, Chicago; Illinois 60680Search for more papers by this authorP. H. EISELE, P. H. EISELE Animal Resources Service, School of Veterinary Medicine, University of California, Davis, California 95616Search for more papers by this author First published: November 1987 https://doi.org/10.1111/j.1749-6632.1987.tb32955.x a Supported by National Institutes of Health Grants GM29520, GM33415, and RCDA K04GM00503 to A.M.W. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Volume508, Issue1Physiological NMR Spectroscopy: From Isolated Cells to ManNovember 1987Pages 523-526 RelatedInformation
Perioperative care and anesthetic management of donor and recipient animals are crucial factors in studies involving experimental liver transplantation in the pig. Prevention of unacceptably high morbidity and mortality in the transplant recipients requires meticulous attention to anesthesia, preoperative and postoperative care. Liver transplant surgeries were performed using 15 pairs of pigs. Six of the transplant recipients were anesthetized with halothane plus 50% nitrous oxide (N2O) and oxygen (O2), and nine with isoflurane plus 50% N2O in O2. Arterial blood pressure, total anesthetic time, time of interruption of vena cava blood flow, and fluids administered, as well as length of survival were among the parameters measured and compared for the two groups. No deaths were attributed to either anesthetic technique. However, the isoflurane group had slightly higher blood pressure intraoperatively, better long range survival, and relatively rapid recoveries when compared to the halothane group. Because of these findings and the reported low rate of isoflurane metabolism and low resultant potential for formation of toxic metabolites when compared to halothane metabolism, we have elected to use the isoflurane-50% N2O regimen for this procedure.
The minimum alveolar concentration (MAC) of isoflurane in oxygen (O2) was determined to be 1.55 +/- 0.08 (SEM) volumes % in twelve pigs (Sus scrofa). Values for isoflurane MAC in the presence of 50% (I-50%N2O) and 66% (I-66%N2O) nitrous oxide were determined in nine and six of these same animals, respectively, and equalled 1.03 +/- 0.05 vol % for I-50%N2O and 0.95 +/- 0.07 vol % for I-66%N2O. Animals respired spontaneously and arterial blood pressure (AP), heart rate (HR), rectal body temperature, and arterial blood gases (PO2, PCO2, and pH) were recorded throughout the study period. These parameters were within normal limits near MAC for all three gas combinations. The MAC for isoflurane in swine was similar to that for other animals and, man and the use of this agent was associated with rapid and uneventful anesthetic induction and recovery. The addition of 50% and 66% nitrous oxide (N2O) reduced the isoflurane MAC by 30% and 42%, respectively.