Anesthesia and Analgesia in Rabbits and Rodents

Rabbits and rodents are popular pets and are often presented to veterinarians for evaluation and medical treatment. Anesthesia in exotic pets is required for many diagnostic and surgical procedures and is associated with a higher perioperative risk in rabbits and rodents when compared with dogs and cats. Inhalation anesthetic agents are commonly used as the sole source of anesthesia in small rodents, whereas injectable agents in combination with inhalation anesthesia are often used for rabbits and larger rodents. Analgesia is an important component of exotic pet medicine. Although it may be difficult to recognize signs of pain in companion exotic mammals, adequate pain management should always be provided. Opioid and nonsteroidal antiinflammatory drugs are the analgesic medications of choice, but others should be considered (e.g., local anesthetic agents). This article provides an update of the current literature regarding anesthesia and analgesia in rabbits and rodents.     

An investigation into the practices of dairy producers and veterinarians in dehorning dairy calves in Ontario

The objective of this survey was to describe the current state of dehorning practices by dairy producers and veterinarians in Ontario and to identify opportunities to improve on existing practices. Two hundred and seven producers and 65 veterinarians completed a survey on dehorning practices during the summer of 2004. Seventy-eight percent of dairy producers dehorn their own calves; 22% use local anesthetics. Veterinarians dehorn calves for 31% of dairy clients; 92% use local anesthetics. Pain management was the most common reason for use of local anesthetics for both groups, while time (veterinarians) and time and cost (producers) were the most common reasons for lack of use. Producers who used local anesthetics were 6.5 times more likely to have veterinary involvement in their dehorning decisions. Thirteen percent of producers were unaware of the options for pain management. These results suggest that veterinarians should take the initiative to educate their clients about the options for pain management.     

Anesthetic management of thoracotomy

Successful anesthesia for thoracic surgery requires an understanding of the clinical disease and the physiologic changes accompanying the disease, as well as anesthetic agents available for use. The authors discuss selection of appropriate anesthetic drugs, perioperative management considerations, pharmacologic support, intraoperative monitoring and postoperative pain management.     

Cost comparison of anesthetic regimens in the dog and cat

Comparative costs of anesthetic regimens for the dog and cat were calculated. Various combinations of currently popular sedatives, tranquilizers, and anti-muscarinics (preanesthetic drugs), and anesthetic induction and maintenance drugs were studied. The preanesthetic drug affected overall anesthetic cost through its own cost, its effect on the amount of anesthetic drug necessary for intubation, and its effect on the amount of anesthetic necessary to maintain anesthesia. The combination of acetylpromazine-thiamylal-halothane was the least expensive regimen for both the dog and cat, whereas drug combinations that included isoflurane as the maintenance drug were the most expensive. In the cat, induction of anesthesia by use of N2O, O2, and halothane in a plexiglas chamber was more expensive than by the use of thiamylal.     

Ferret, rabbit, and rodent anesthesia.

Ferrets, rabbits, and rodents are increasingly being presented to veterinarians for evaluation and treatment. The owners of these animals expect high-level medical and surgical care. Consequently, veterinarians are more often required to provide intensive anesthetic management of these animals. The variability of anesthetic agents used and patient responses are addressed. The consequences of size for anesthetic management are discussed. Successful small mammal anesthesia requires following general anesthetic principles, awareness of limitations, and maintenance of high standards of care.     

Canadian veterinarians' use of analgesics in cattle, pigs, and horses in 2004 and 2005

Anecdotal evidence suggests that many veterinarians may not use analgesics in livestock for routine surgical procedures or painful disease states. To investigate this, we conducted a national mail survey of a random sample of 1431 Canadian veterinarians (response rate, 50.1%). Questions primarily concerned veterinarians' analgesic usage for common surgeries and medical conditions in beef and dairy cattle, pigs, and horses, and attitudes toward pain management. More than 90% of veterinarians used analgesic drugs for equine surgeries, for cesarean section in sows and cows, and for bovine claw amputation and omentopexy. However, in these and other categories, the analgesics used were often inadequate, and many veterinarians did not give analgesics to young animals. When castrated, < 0.001% of piglets received analgesia, compared with 6.9% of beef calves and 18.7% of dairy calves < or = 6 mo of age, 19.9% of beef calves and 33.2% of dairy calves > 6 mo of age, and 95.8% of horses. Respondents largely agreed that there are no long-acting, cost-effective analgesics available for use in livestock (median rating 8/10; interquartile range 4-9), and that the long or unknown withdrawal periods of some drugs outweighed the benefits of using them (median rating 7/10; interquartile range 4-9). The results indicate an urgent need for veterinarians to manage pain in livestock better. Continuing education would help, as would an increase in the number of approved, cost-effective analgesic drugs with known withdrawal periods.     

Newer diagnostic and surgical techniques and their impact on anesthesia.

There are several newer diagnostic and surgical techniques available to veterinarians today. Careful anesthetic management is essential when using these modalities both to avoid accidents and to enable their use. For example, total intravenous anesthetic techniques can be used if the airway is occupied by an endoscope or laser surgery is being performed in the airway. The anesthesiologist must also be aware of the physiological changes that may occur during procedures such as laparoscopy and act to minimize their impact on patients.     

Current attitudes to,and use of,peri-operative analgesia in dogs and cats by veterinarians in New Zealand

AIM: To investigate the attitudes of veterinary practitioners in New Zealand to pain and analgesia, and their use of analgesic drugs, in dogs and cats.

METHODS: A questionnaire posted to 1,200 practising veterinarians was used to gather information about the use of analgesia in dogs and cats, assessment of pain, attitudes to pain relief, analgesic drugs and procedures used, factors affecting choice of analgesic agent, and veterinary demographics, continuing education and staffing.

RESULTS: Three hundred and twenty questionnaires with useable data were returned, a response rate of 28%. Male and female veterinarians were evenly represented. The analgesic agents most commonly used were morphine (opioids) and carprofen (a non-steroidal anti-inflammatory drug; NSAID). Use of peri-operative pain relief ranged from 50% for castration of cats to 91% for fracture repair in dogs. For most procedures, female veterinarians scored pain at a significantly higher level than their male colleagues. Fifty-eight percent of respondents considered their knowledge in the area of assessment and treatment of pain was adequate.

CONCLUSIONS: This survey was considered representative of veterinarians working in companion animal practice in New Zealand. Results indicated a relatively high use of peri-operative analgesia, including both pre-emptive and multi-modal analge- sia, in cats and dogs, although there was still some disparity between the perception of how painful a procedure was and the consequent use of pain relief.

CLINICAL RELEVANCE: The establishment of current attitudes and practices indicates to practising veterinarians how their own use of analgesics compares with that of their colleagues. It also provides information to educators on potential areas of focus, given that 42% of respondents felt their knowledge in the area of assessment and treatment of pain was inadequate.     

Perioperative use of selective alpha-2 agonists and antagonists in small animals

Alpha-2 agonists are the only single class of anesthetic drugs that induce reliable, dose-dependent sedation, analgesia, and muscle relaxation in dogs and cats. Used at low doses, as adjuncts to injectable and inhalational anesthetics, selective alpha-2 agonists dramatically reduce the amount of anesthetic drug required to induce and maintain anesthesia. This reduction in anesthetic requirements is achieved without significant depression of pulmonary function and with limited effects on cardiovascular function. Selective alpha-2 agonists can also be used postoperatively to potentiate the analgesic effects of opioids and other drugs. Given the nearly ideal pharmacodynamic profile and reversibility of alpha-2 agonists, these drugs will play a central role in balanced approaches to anesthesia and the management of perioperative pain in healthy dogs and cats.     

Anesthetic protocols for common emergencies.

Anesthesia, sedation, and pain management should be taken seriously in the emergency patient. Proper knowledge of the drugs available and their pharmacokinetics and pharmacodynamics are necessary to administer anesthesia safely to critical patients. A proactive approach regarding monitoring, titration of anesthetic drugs, and anticipation of life-threatening complications helps in achieving successful anesthetic outcomes.     

Current British veterinary attitudes to perioperative analgesia for dogs.

In March 1996, a questionnaire was sent to 2000 veterinary surgeons, primarily involved in small animal practice, to assess their attitudes to perioperative analgesic therapy in dogs, cats and other small mammals. This paper is concerned only with the data relating to dogs. The veterinary surgeons considered that pain was a consequence of all the surgical procedures specified, but there were differences in their treatment of pain. Some veterinarians considered that a degree of pain was necessary postoperatively to prevent excessive activity. In general, women and more recent graduates assigned higher pain scores to the procedures and were more likely to treat the pain with analgesics. A significant number of veterinarians consider the use of opiates or non-steroidal anti-inflammatory drugs before surgical procedures, but relatively few appear to use combinations of different classes of analgesics either before or after operations.     

Current attitudes to, and use of, peri-operative analgesia in dogs and cats by veterinarians in New Zealand

AIM: To investigate the attitudes of veterinary practitioners in New Zealand to pain and analgesia, and their use of analgesic drugs, in dogs and cats. METHODS: A questionnaire posted to 1,200 practising veterinarians was used to gather information about the use of analgesia in dogs and cats, assessment of pain, attitudes to pain relief, analgesic drugs and procedures used, factors affecting choice of analgesic agent, and veterinary demographics, continuing education and staffing. RESULTS: Three hundred and twenty questionnaires with useable data were returned, a response rate of 28%. Male and female veterinarians were evenly represented. The analgesic agents most commonly used were morphine (opioids) and carprofen (a non-steroidal anti-inflammatory drug; NSAID). Use of peri-operative pain relief ranged from 50% for castration of cats to 91% for fracture repair in dogs. For most procedures, female veterinarians scored pain at a significantly higher level than their male colleagues. Fifty-eight percent of respondents considered their knowledge in the area of assessment and treatment of pain was adequate. CONCLUSIONS: This survey was considered representative of veterinarians working in companion animal practice in New Zealand. Results indicated a relatively high use of peri-operative analgesia, including both pre-emptive and multi-modal analgesia, in cats and dogs, although there was still some disparity between the perception of how painful a procedure was and the consequent use of pain relief. CLINICAL RELEVANCE: The establishment of current attitudes and practices indicates to practising veterinarians how their own use of analgesics compares with that of their colleagues. It also provides information to educators on potential areas of focus, given that 42% of respondents felt their knowledge in the area of assessment and treatment of pain was inadequate.     

Options in dairy data management.

A great deal of progress has been made in the development of dairy herd management software in the last few years. At the same time, the speed, capacity, and portability of computer hardware have increased, while costs have decreased, thus encouraging use by veterinarians, dairy herd managers, and other industry support groups. A review of the literature indicates that an increasing number of producers, veterinarians, and other dairy industry service personnel are using computers and dairy herd management software in the delivery of their services (1-3,5,9-11,26-30,38,39). Wider adoption will occur if information generated through the use of these systems is directed towards the improvement of the profitability of dairy production. The quality of a decision is only as good as the information used to make it. In the past, the limited availability of reliable herd data has restricted our understanding of factors that influence herd performance. In essence, we must define what is normal before we can determine what is abnormal. More importantly, we must define what management practices are profitable and to what extent they increase revenue (31,32). Improved record keeping will benefit the dairy industry by allowing producers and dairy consultants to make profitable decisions based on more accurate and complete information. The ability to merge biological, management, and economic data may prove valuable in the evaluation of intervention at the herd and individual animal level.(ABSTRACT TRUNCATED AT 250 WORDS)     

Anesthetic and analgesic techniques used for dogs undergoing ovariohysterectomies in general practice in the United States

ObjectiveTo acquire information about anesthesia and analgesia protocols used by United States (US) veterinarians in primary care practices when performing routine ovariohysterectomy in dogs.Study designCross-sectional survey.PopulationPrimary care veterinarians in the US.MethodsAn online anonymous survey, originally created in New Zealand, was modified with permission and made available to Veterinary Information Network (VIN) members. The survey asked questions about performing ovariohysterectomy in healthy adolescent dogs in the categories of preanesthetic evaluation, premedication and induction protocols, maintenance protocols and monitoring equipment, and postoperative analgesic and sedation protocols and pain assessments.ResultsA total of 1213 US veterinarians completed the survey. Respondents (n; %) reported performing preoperative laboratory tests [packed cell volume (135; 11%), complete blood cell count (889; 73%) and biochemistry panels (1057; 87%)] and preanesthetic examinations on the morning of surgery (1083; 90%). The most commonly administered drugs for premedication were acepromazine (512; 42%), hydromorphone (475; 39%) or butorphanol (463; 38%), with propofol (637; 67%) for induction of anesthesia and isoflurane (882; 73%) for maintenance of anesthesia. Most veterinarians reported placing intravenous catheters (945; 78%), administering electrolyte solutions (747; 67%) and providing heat support (1160; 96%). Perioperative and postoperative analgesia included local anesthetics (545; 45%), opioids (844; 70%) and non-steroidal anti-inflammatory drugs (NSAIDs) (953; 79%); NSAIDs were dispensed for home use (985; 81%). Dogs were most frequently discharged on the day of surgery (1068; 88%) and the owners were contacted (914; 75%) for follow-up within 1–2 days.Conclusions and clinical relevanceAnesthetic management for routine ovariohysterectomy in dogs varies among US veterinary VIN members. Information from this study is useful for all veterinarians for comparison with their practice management and for teachers of veterinary anesthesia to continue to emphasize options for analgesia.     

Pain management and regional anesthesia for the dental patient

Current standards of care in veterinary medicine dictate an adequate level of pain control for our patients. Effective pain control uses a proactive, multimode approach that starts with preoperative medications, includes the anesthetic protocol selected, and continues into the postoperative period. A basic understanding of the physiology of pain assists in selecting those agents and modalities best suited for individual patients. Analgesic drug selection and local anesthesia are both integral parts of pain control when performing surgery in the oral cavity. Local (regional) anesthesia plays an important part in the pain control of oral surgical patients. Regional anesthetic techniques are used for many common oral procedures, including extractions, periodontal flap surgery, treatment of traumatic injuries of the oral cavity, tumor removal, palatal surgery, periodontal therapy, and root canal therapy. This presentation will cover strategies for analgesia and the techniques and materials used in local/regional anesthesia in the oral cavity. Anatomic landmarks and guidelines for effective regional blocks will be covered.     

Use of the Food Animal Residue Avoidance Databank (FARAD)

OBJECTIVES: To report the results of 3 surveys evaluating the extent that the Food Animal Residue Avoidance Databank (FARAD) is used by veterinarians, the profession's perception of the need for the program, barriers that prevent veterinarians from fully using the service, and the perceptions that animal production industry groups have regarding FARAD. DESIGN: Telephone and mail surveys were used to collect information using cross-sectional, case-control, and directed sample studies. SAMPLE POPULATION: Food animal veterinarians and veterinarians and nonveterinarians in allied animal industries or with special interest in production animal medicine. RESULTS: The use of FARAD was high among dairy and general practitioners, but low among beef practitioners and veterinarians with minor commitment to food animal medicine. Solo practitioners and veterinarians with less than 13 years in practice were less likely to use FARAD. Dairy practitioners who had not used FARAD were most likely to prescribe extralabel products. CLINICAL IMPLICATIONS: Results imply that dairy and general food animal practitioners have either greater need or access through educational networks and are more aware of FARAD than practitioners who work with beef and those with a minor component of their practice involving food animals. The difference in familiarity and use of FARAD between practice type is an important finding, but the root of the difference is not clear; it may be attributable to a difference in the effectiveness of knowledge transfer for the groups, or the message is ignored because the issue of drug residues is less compelling for veterinarians and their clients in the beef sector.     

Protocols for anesthesia of cattle.

The article explores the choices and considerations pertinent to the selection of an anesthetic protocol for use in cattle. When the veterinarian is presented with the opportunity to provide anesthesia for surgical or diagnostic procedures, the options include use of local anesthetics, sedative-tranquilizer and analgesic combinations, or general anesthetic techniques. Informed decisions regarding selection of an anesthetic technique or protocol are made possible with understanding of the perianesthetic considerations commonly recognized for cattle.     

Clinical pain management techniques for cats

Although pain management is an emerging and popular topic in veterinary medicine, use of analgesics in cats has received little attention relative to their canine counterparts. Some of the difficulty lies in assessment of whether or not a cat is in pain. Simple observation of a cat in a cage relies upon overt expression of pain, and is often inaccurate. Pain scales have been developed that allow a semiquantitative evaluation of the degree of pain an animal may be experiencing. However, treating pain based upon observation of the painful state is less effective than anticipating and preemptively treating pain. This article reviews specific methods for preemptively treating and alleviating pain in the cat. The traditional approach to pain management involves drug administration. Specific categories of agents used in cats include opioids, nonsteroidal anti-inflammatories, or alpha-2 agonists. Other modalities of pain management, which are also reviewed, include use of local anesthetic drugs for local and regional analgesia, as well as acupuncture.