Duration, complications, stress, and pain of open ovariohysterectomy versus a simple method of laparoscopic-assisted ovariohysterectomy in dogs

OBJECTIVE: To describe a simple method of laparoscopic-assisted ovariohysterectomy (LAOHE) and compare duration of surgery, complications, measures of surgical stress, and postoperative pain with open ovariohysterectomy (OHE) in dogs. DESIGN: Randomized, prospective clinical trial. ANIMALS: 20 healthy sexually intact female dogs weighing >10 kg (22 lb). PROCEDURES: Dogs were randomly allocated to receive conventional OHE or LAOHE. Intraoperative complications, anesthetic complications, total anesthesia time, and total surgery time were recorded. Serum cortisol and glucose concentrations, temperature, heart rate, and respiratory rate were measured preoperatively and 1, 2, 4, 6, 12, and 24 hours postoperatively. Pain scores were assigned by a nonblinded observer at 1, 2, 4, 6, 12, and 24 hours postoperatively. Duration of surgery, pain scores, objective measures of surgical stress, anesthetic complications, and surgical complications were compared between OHE and LAOHE. RESULTS: Age, weight, PCV, and duration of surgery did not differ between treatment groups. Nine of 10 dogs in the OHE group required additional pain medication on the basis of pain scores, whereas none of the dogs in the LAOHE group did. Blood glucose concentrations were significantly increased from preoperative concentrations in the OHE group at 1, 2, 4, and 6 hours postoperatively and at 1 hour postoperatively in the LAOHE group. Cortisol concentrations were significantly increased at 1 and 2 hours postoperatively in the OHE group. CONCLUSIONS AND CLINICAL RELEVANCE: LAOHE caused less pain and surgical stress than OHE and may be more appropriate for an outpatient setting.     

Effect of administration of nonsteroidal anti-inflammatory drugs before surgery on renal function in clinically normal dogs

OBJECTIVES: To investigate renal function in clinically normal dogs undergoing general anesthesia for ovariohysterectomies that received nonsteriodal antiinflammatory drugs (NSAID) before surgery. ANIMALS: 40 clinically normal dogs. PROCEDURE: After induction of anesthesia, dogs were given an analgesic. Renal function was assessed before surgery and 24 and 48 hours after surgery by means of serum urea and creatinine concentrations, fractional clearance of sodium (FC(Na)), urine gamma-glutamyltransferase (GGT) and alkaline phosphatase (ALP) activities, and urine analysis. Ten dogs in each of 4 groups received ketorolac tromethamine (0.5 mg/kg of body weight), ketoprofen (1 mg/kg), carprofen (4 mg/kg), or morphine (0.1 mg/kg; control group). RESULTS: Duration of general anesthesia ranged from 1.75 to 5 hours, with a mean of 3 hours. Two ketorolac- and 2 ketoprofen-treated dogs had transient azotemia. A significant decrease in the FC(Na) between before surgery and 24 hours after surgery, and between before surgery and 48 hours after surgery, was found in ketoprofen- and carprofen-treated dogs. Ketorolac-, ketoprofen-, and morphine-treated dogs had a decrease in urine specific gravity. Two ketorolac, 1 ketoprofen-, 1 carprofen-, and 4 morphine-treated dogs had increases in renal tubular epithelial cells on urine sediment examination 24 hours after surgery. CONCLUSIONS AND CLINICAL RELEVANCE: In clinically normal dogs undergoing general anesthesia and elective surgery, the use of NSAID as analgesics is not contraindicated. Compared with ketorolac or ketoprofen, carprofen had the least effect on renal function and integrity.     

Effects of general anesthesia and surgery on renal function in healthy dogs

OBJECTIVES: To evaluate renal function in healthy dogs undergoing general anesthesia and ovariohysterectomy without concurrent IV administration of fluids. ANIMALS: 35 healthy client-owned dogs. PROCEDURE: Dogs were medicated with promazine hydrochloride (0.05 mg/kg of body weight, SC) approximately 45 minutes before induction of anesthesia with thiopental sodium (10 to 15 mg/kg, IV). Anesthesia was maintained with 2% halothane in oxygen. Ovariohysterectomies were performed by senior veterinary students under the direct supervision of a veterinary surgeon. Renal function was assessed (serum urea and creatinine concentrations, fractional clearance of sodium, urine alkaline phosphatase [ALP] and gamma-glutamyltransferase [GGT] activities, urine specific gravity, and enumeration of renal tubular epithelial cells in urine sediment) prior to and 24 and 48 hours after surgery. RESULTS: Duration of general anesthesia ranged from 80 to 310 minutes. Urine specific gravity and ALP activity and serum urea and creatinine concentrations did not change over time. Fractional clearance of sodium decreased 24 and 48 hours after surgery, whereas urine GGT activity and the ratio of urine GGT activity to urine creatinine concentration increased 24 hours after surgery, compared with presurgery values. Renal tubular epithelial cells increased in number in urine sediment from 11 of 35 (31.4%) dogs and 5 of 35 (14.3%) dogs 24 and 48 hours after surgery, respectively. However, this increase was not clinically relevant. CONCLUSIONS AND CLINICAL RELEVANCE: Intravenous administration of fluids to healthy dogs undergoing general anesthesia and elective surgery may not be necessary for maintenance of renal homeostasis.     

Influence of Isoflurane General Anesthesia or Anesthesia and Surgery on Thyroid Function Tests in Dogs

Background: Anesthesia and surgery affect thyroid function tests in humans but have not been studied in dogs. Hypothesis: Anesthesia and anesthesia with surgery will affect thyroid function tests in dogs. Animals: Fifteen euthyroid dogs. Methods: Prospective, controlled, interventional study. Dogs were assigned to one of 3 groups: control, general anesthesia, and general anesthesia plus abdominal exploratory surgery. Dogs in the anesthesia and surgery groups were premedicated with acepromazine and morphine, induced with propofol, and maintained on isoflurane. Samples for measurement of serum thyroxine (T₄), free T₄ (fT₄) by equilibrium dialysis, triiodothyronine (T₃), reverse T₃ (rT₃), and thyroid‐stimulating hormone concentrations were collected from each dog immediately before premedication, at multiple times during anesthesia, surgery, 4, 8, 12, 24, 36, and 48 hours after anesthesia, once daily for an additional 5 days, and once 14 days after anesthesia. Sampling was performed at identical times in the control group. Results: Serum T₄ decreased significantly from baseline in the surgery and anesthesia groups compared with the control group at 0.33 (P= 0.043) and 1 hour (P= 0.018), and 2 (P= 0.031) and 4 hours (P= 0.037), respectively, then increased significantly in the surgery group compared with the control group at 24 hours (P= 0.005). Serum T₃ decreased significantly from baseline in the anesthesia group compared with the control group at 1 hour (P= 0.034). Serum rT₃ increased significantly from baseline in the surgery group compared with the control and anesthesia groups at 8 (P= 0.026) and 24 hours (P= 0.0001) and anesthesia group at 8, 12, 24, and 36 hours (P= 0.004, P= 0.016, P= 0.004, and P= 0.014, respectively). Serum fT₄ increased significantly from baseline in the surgery group compared to the control at 24 hours (P= 0.006) and at day 7 (P= 0.037) and anesthesia group at 48 hours (P= 0.023). Conclusions and Clinical Importance: Surgery and anesthesia have a significant effect on thyroid function tests in dogs.     

Comparison of cardiopulmonary responses during sedation with epidural and local anesthesia for laparoscopic-assisted jejunostomy feeding tube placement with cardiopulmonary responses during general anesthesia for laparoscopic-assisted or open surgical jejunostomy feeding tube placement in healthy dogs

OBJECTIVE: To evaluate the use of laparoscopic-assisted jejunostomy feeding tube (J-tube) placement in healthy dogs under sedation with epidural and local anesthesia and compare cardiopulmonary responses during this epidural anesthetic protocol with cardiopulmonary responses during general anesthesia for laparoscopic-assisted or open surgical J-tube placement. ANIMALS: 15 healthy mixed-breed dogs. PROCEDURES: Dogs were randomly assigned to receive open surgical J-tube placement under general anesthesia (n = 5 dogs; group 1), laparoscopic-assisted J-tube placement under general anesthesia (5; group 2), or laparoscopic-assisted J-tube placement under sedation with epidural and local anesthesia (5; group 3). Cardiopulmonary responses were measured at baseline (time 0), every 5 minutes during the procedure (times 5 to 30 minutes), and after the procedure (after desufflation [groups 2 and 3] or at the start of abdominal closure [group 1]). Stroke volume, cardiac index, and O(2) delivery were calculated. RESULTS: All group 3 dogs tolerated laparoscopic-assisted J-tube placement under sedation with epidural and local anesthesia. Comparison of cardiovascular parameters revealed a significantly higher cardiac index, mean arterial pressure, and O(2) delivery in group 3 dogs, compared with group 1 and 2 dogs. Minimal differences in hemodynamic parameters were found between groups undergoing laparoscopic-assisted and open surgical J-tube placement under general anesthesia (ie, groups 1 and 2); these differences were not considered to be clinically important in healthy research dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Sedation with epidural and local anesthesia provided satisfactory conditions for laparoscopic-assisted J-tube placement in healthy dogs; this anesthetic protocol caused less cardiopulmonary depression than general anesthesia and may represent a better choice for J-tube placement in critically ill patients.     

Development of a scale to evaluate postoperative pain in dogs

OBJECTIVE: To design and evaluate a scale for measurement of postoperative pain in dogs. DESIGN: Randomized, blinded, prospective study, with positive- and negative-control groups. ANIMALS: 36 dogs undergoing general anesthesia for ovariohysterectomy and 12 dogs undergoing general anesthesia without surgery. PROCEDURE: A pain assessment scale was developed for dogs, which incorporated physiologic data (heart and respiratory rates) and behavioral responses (response to palpation, activity, mental status, posture, and vocalization). This pain scale was then applied to a study in which dogs were allocated to 2 groups, depending on the type of medication administered (acepromazine maleate only or acepromazine and butorphanol) before induction of general anesthesia. The 36 dogs that had ovariohysterectomy were allocated to 3 groups, members of which received butorphanol, carprofen, or no analgesic after surgery. Dogs were scored for signs of pain and videotaped at 0, 1, 2, 4, 6, 8, 12, and 18 hours after surgery by an assessor who was blinded to the groups. Results were analyzed for significant differences in pain scores for single categories and total pain scores among groups. Video segments were scrambled and then scored by a second external assessor to test the repeatability of the results, using the pain assessment scale. RESULTS: Mean total pain scores were significantly different between the group of dogs that underwent general anesthesia only and each group of dogs that underwent general anesthesia and surgery. Pain scores for the analgesic-treatment groups reflected the known onset and duration of action of the analgesic used. Agreement between the internal and external assessors was excellent and indicated high precision between the 2 assessors for the population of dogs as a whole. CLINICAL IMPLICATIONS: Behavioral and physiologic measurements can be used reliably to evaluate degree of pain in dogs during the postoperative period and their response to analgesics.     

Comparison of Short‐ and Long‐term Function and Radiographic Osteoarthrosis in Dogs After Postoperative Physical Rehabilitation and Tibial Plateau Leveling Osteotomy or Lateral Fabellar Suture Stabilization

Objectives— To compare short‐ and long‐term functional and radiographic outcome of cranial cruciate ligament (CrCL) injury in dogs treated with postoperative physical rehabilitation and either tibial plateau leveling osteotomy (TPLO) or lateral fabellar suture stabilization (LFS). Study Design— Prospective observational clinical study. Animals— Medium to large breed dogs with naturally occurring CrCL injury (n=65). Methods— Dogs with CrCL injury were treated with either TPLO or LFS and with identical physical rehabilitation regimes postoperatively. Limb peak vertical force (PVF) was measured preoperatively and at 3, 5, and 7 weeks, and 6 months and 24 months postoperatively. Stifles were radiographically assessed for osteoarthrosis (OA) preoperatively and 24 months postoperatively. Results— Thirty‐five dogs had LFS and 30 dogs had TPLO. Radiographic OA scores were significantly increased at 24 months compared with preoperative scores in all dogs. Radiographic OA scores preoperatively and at 24 months were not significantly different between treatment groups. PVF was significantly increased from preoperative to 24 months among both treatment groups but not significantly different between treatment groups preoperatively or at 3, 5, 7 weeks, 6, or 24 months. Conclusion— No significant difference in outcome as determined by ground reaction forces or radiographic OA scores were found between dogs with CrCL injury treated with LFS or TPLO. Clinical Relevance— LFS and TPLO remain good options for stabilizing stifles with CrCL injury with all dogs showing significant functional improvement. This study does not support the superiority of either surgical technique.     

Surgical decompression in dogs with thoracolumbar intervertebral disc disease and loss of deep pain perception: A retrospective study of 46 cases

The case details and outcome after surgical decompression of 46 dogs with thoracolumbar intervertebral disc disease with loss of deep pain perception prior to surgery were reviewed. Nineteen dogs (41.3%) recovered with a median follow-up period of 12.5 months. Recovery was defined as an ambulatory paraparesis, or better, with urinary and fecal continence. There was a better outcome in dogs with loss of deep pain for less than 24 hours prior to surgery (19/41; 46.3% recovered) than in dogs without deep pain perception for more than 24 hours (0/5; 0% recovered). Dogs with deep pain perception present at two weeks postoperatively had significantly higher success rate (8/12; 66.7% recovered) than dogs without deep pain perception at this time period (1/10; 10.0% recovered). The return of deep pain perception by two weeks postoperatively can be a useful positive prognostic indicator.     

Surgical Decompression in Dogs with Thoracolumbar Intervertebral Disc Disease and Loss of Deep Pain Perception: A Retrospective Study of 46 Cases

The case details and outcome after surgical decompression of 46 dogs with thoracolumbar intervertebral disc disease with loss of deep pain perception prior to surgery were reviewed. Nineteen dogs (41.3%) recovered with a median follow-up period of 12.5 months. Recovery was defined as an ambulatory paraparesis, or better, with urinary and fecal continence. There was a better outcome in dogs with loss of deep pain for less than 24 hours prior to surgery (19/41; 46.3% recovered) than in dogs without deep pain perception for more than 24 hours (0/5; 0% recovered). Dogs with deep pain perception present at two weeks postoperatively had significantly higher success rate (8/12; 66.7% recovered) than dogs without deep pain perception at this time period (1/10; 10.0% recovered). The return of deep pain perception by two weeks postoperatively can be a useful positive prognostic indicator.     

Effect of prolonged general anesthesia with sevoflurane and laparoscopic surgery on gastric and small bowel propulsive motility and pH in dogs

ObjectiveTo determine if general anesthesia with sevoflurane and laparoscopic surgery changed gastric and small bowel propulsive motility or pH in dogs.Study designProspective, controlled trial.AnimalsTwelve, 19–24 months old, female, Treeing Walker Hound dogs, weighing 23–30 kg.MethodsDogs were anesthetized for a median of 8.5 hours during another study to determine the minimum alveolar concentration of sevoflurane using a visceral stimulus. Gastric and small bowel motility were determined using a sensor capsule that measures pressure, pH and temperature. Gastric transit time and motility index were calculated. For 8/12 dogs, gastric motility, pH and transit time were measured. In 4/12 dogs, small bowel motility and pH were measured.ResultsAnesthesia decreased gastric and small bowel motility but did not change luminal pH. Mean gastric contraction force decreased from median (range) 11 (8–20) to 3 (1–10) mmHg (p < 0.01) and gastric motility index decreased from 0.63 (0–1.58) to 0 (0–0.31; p = 0.01). Frequency of contractions did not change, 3.7 (1.6–4.4) versus 2.8 (0.1–5.1) contractions minute^?1 (p = 0.1). Gastric motility returned to normal 12–15 hours following anesthesia. Gastric emptying was prolonged from 12 (5.3–16) to 49 (9.75–56.25) hours (p < 0.01). Mean small bowel contraction force decreased from 34 (24–37) to 3 (0.9–17) mmHg (p < 0.02) and motility index decreased from 3.75 (1–4.56) to 0 (0–1.53; p = 0.02). Frequency of contractions did not change, 0.5 (0.3–1.4) versus 1.4 (0.3–4.6) contractions minute^?1 (p = 0.11). Small bowel motility returned within 2 hours after anesthesia. Laparoscopy did not result in changes to gastric or small bowel parameters beyond those produced by general anesthesia.Conclusions and clinical relevanceThe force of gastric and small bowel contractions decreased during sevoflurane anesthesia for laparoscopy. Although gastric motility returned to normal within 12–15 hours the impairment of gastric emptying lasted 30–40 hours, predisposing dogs to postoperative ileus.     

Effect of fasting on thyroxine, 3,5,3'-triiodothyronine, and cortisol concentrations in serum of dogs

The present study was designed to compare basal and stimulated concentrations of 3,5,3'-triiodothyronine (T3), thyroxine (T4), and cortisol in serum of dogs fasted 12 or 18 hours (to represent overnight fasting) or 24 or 36 hours (to represent prolonged inappetence) with those of dogs that were not fasted. Twenty-five adult Beagle bitches were allotted to 5 experimental fasting groups (0, 12, 18, 24, and 36 hours). Blood samples for hormonal analyses were obtained 4, 3, 2, and 1 hour before food was removed; at the time of food removal; 1 hour after food was removed; and every 2 hours during experimental fasting until 0800 hours on the day fasting ended. Dogs were injected with 5 IU of thyrotropin, IV, and 2.2 IU of adrenocorticotropin/kg, IM, to evaluate thyroidal and adrenocortical endocrine reserves. Additional blood samples were collected 0.5, 1, 2, 3, and 4 hours after injections were given. Serum concentrations of T3, T4, and cortisol were determined by validated radioimmunoassays. Body weights and ages of the dogs and food consumption during a 2-hour preliminary feeding period before dogs were fasted did not differ among fasting groups. Length of fasting did not affect serum concentrations of T3 or T4 in dogs at 12, 18, 24, or 36 hours after food was removed. Mean serum concentrations of cortisol in dogs fasted 12 or 24 hours were lower than those in dogs that were not fasted. Serum concentrations of the hormones after thyrotropin and adrenocorticotropin were injected were not affected by fasting.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of inspired air heat and humidification on anesthetic-induced hypothermia in dogs

Dogs were evaluated for efficacy of inspired air heating and humidification in maintenance of body temperature during general anesthesia. Three separate trials were conducted: (i) a control group without thermal support (n = 5), (ii) a group supported only by a heated humidifier device placed in the inspiratory limb of an anesthesia circle delivery system (n = 7), and (iii) a group supported by combination of inspired air humidification and recirculating water blanket (n = 7). A significant difference (P greater than 0.4) was not noticed in temperature changes between control and humidifier-supported groups. A significant advantage (P less than 0.05) was noticed between the combined support and the humidifier or control groups. Seemingly, during general anesthesia, use of combined thermal support is significantly better than airway humidification for maintenance of normothermia in the dog.     

Comparison of metrizamide and iohexol for cisternal myelographic examination of dogs

A double-blind study, using metrizamide, iohexol, or Ringer's solution (control) as cisternal myelographic agents, was performed on 25 dogs. Before myelographic examination was done, each dog was subjected to physical, clinical pathologic, and neurologic examinations, as well as examinations by electroencephalography and computerized tomography. These were repeated 24 hours after completion of the myelographic examination. The group of dogs given metrizamide (group II) had a significantly greater occurrence of seizure activity (6 of 10) than did the control dogs (group I; 0 of 5) or dogs given iohexol (group III; 0 of 10; P less than 0.003). In group II, the CSF microprotein concentration was significantly greater 24 hours after myelography was done than were the values in groups I and III (P less than 0.003). Myelograms of the group II dogs (metrizamide) and group III dogs (iohexol) had similar diagnostic qualities. At 24 hours after myelographic examination was done, computerized tomography scan revealed that each dog given metrizamide and iohexol had myelographic contrast material in the brain and cervical spinal cord parenchyma. Seemingly, iohexol has good diagnostic quality, but is less epileptogenic than metrizamide when used in cervical myelographic examinations of dogs.     

Comparison of Three Methods for Relief of Pain After Ear Canal Ablation in Dogs

This study compared three methods of pain relief in dogs that had total ear canal ablation with lateral bulla osteotomy. The hypothesis was that systemic opioids with preoperative local nerve blocks would provide superior pain relief. Thirty-one dogs with chronic otitis externa were included in the study. Dogs were randomly assigned to one of three protocols: systemic opioids alone (10 dogs, group 1), systemic opioids with bupivacaine splash block (11 dogs, group 2), and systemic opioids with preoperative local bupivacaine nerve blocks (10 dogs, group 3). Twenty-one dogs had bilateral ear ablation and 10 had unilateral ablation. Pain was assessed preoperatively, at extubation, 2 hours postextubation, and 1 day postoperatively by a single observer blinded to the analgesic protocol used. Pain scores were not significantly different within or between groups, nor did unilateral versus bilateral ablation have a significant effect on the score. Mean scores were less than 3 (scale 1 to 5) for all groups at all observation times. Rough recoveries were noted in 30% of group 1 dogs, 0% of group 2, and 20% of group 3 dogs. Ninety-four percent of dogs were moderately to heavily sedated at extubation. Sixty percent of group 3 dogs remained moderately to heavily sedated 2 hours postextubation. Rectal temperature, pulse rate, respiratory rate, and postoperative change in serum Cortisol levels were not significantly different between groups. Postoperative increase in blood glucose was significantly higher in groups 1 and 3 compared with preoperative levels. Twenty-three percent of the dogs required additional analgesia or tranquilization after surgery, as determined by the anesthetist; 1 dog in group 1, 2 in group 2, and 4 in group 3. Each of the three analgesic protocols provided similar pain relief in dogs undergoing total ear canal ablation.     

Effect of alternate-day prednisolone administration on hypophyseal-adrenocortical activity in dogs.

OBJECTIVE: To evaluate effect of alternate-day oral administration of prednisolone on endogenous plasma ACTH concentration and adrenocortical response to exogenous ACTH in dogs. ANIMALS: 12 Beagles. PROCEDURE: Dogs were allotted to 2 groups (group 1, 8 dogs treated with 1 mg of prednisolone/kg of body weight; group 2, 4 dogs given excipient only). During a 30-day period, blood samples were collected for determination of plasma ACTH and cortisol concentrations before, during, and after treatment with prednisolone. From day 7 to 23, prednisolone or excipient was given on alternate days. Sample collection (48-hour period with 6-hour intervals) was performed on days 1, 7, 15, 21, and 28; on other days, sample collection was performed at 24-hour intervals. Pre- and post-ACTH plasma cortisol concentrations were determined on days 3, 9, 17, 23, and 30. RESULTS: A significant difference was detected between treatment and time for group 1. Plasma ACTH concentrations significantly decreased for 18 to 24 hours after prednisolone treatment in group-1 dogs. At 24 to 48 hours, ACTH concentrations were numerically higher but not significantly different in group-1 dogs. Post-ACTH plasma cortisol concentration significantly decreased after 1 dose of prednisolone and became more profound during the treatment period. However, post-ACTH cortisol concentration returned to the reference range 1 week after prednisolone administration was discontinued. CONCLUSIONS AND CLINICAL RELEVANCE: Single oral administration of 1 mg of prednisolone/kg significantly suppressed plasma ACTH concentration in dogs for 18 to 24 hours after treatment. Alternate-day treatment did not prevent suppression, as documented by the response to ACTH.     

Analgesic effect of pre-operative etodolac and butorphanol administration in dogs undergoing ovariohysterectomy

The analgesic, bleeding, and renal effects of dogs pre‐medicated with etodolac with and without butorphanol were evaluated. Twenty‐four 1‐year‐old healthy dogs, weighing 19 ± 3 kg (mean ± SD) were randomly assigned to four treatment groups (n = 6): control (C), etodolac (E), butorphanol (B), and etodolac with butorphanol (EB). Etodolac (12–14 mg kg^?1 PO) was given 1 hour before propofol induction and isoflurane maintenance anesthesia. Butorphanol (0.4 mg kg^?1 IV) was given immediately following endotracheal intubation. Control dogs received only propofol (8 mg kg^?1 to effect) and isoflurane anesthesia. All dogs were mechanically ventilated to maintain Pe ′CO₂ between 35 and 45 mm Hg (4.7–6.0 kPa). Lactated Ringer's solution was given at 10 mL kg^?1 hour^?1 during anesthesia. Plasma cortisol concentrations were assessed 1 day prior to surgery (baseline), immediately prior to anesthesia induction, and every 30 minutes until 5 hours following extubation, and 1 day after surgery. Total duration of anesthesia was 50 minutes and total surgery duration was 30 minutes. Isoflurane concentration area under the curve (AUC) over time during the anesthesia was compared among treatment groups. Buccal mucosal bleeding time (BMBT) was assessed 1 day before E administration and during surgery. Urine GGT to urine creatinine ratio, BUN, and plasma creatinine were taken daily from 1 day before to 3 days after surgery. Behavioral pain scores (numerical rating scale) were assessed by two observers blinded to the treatment during the 5‐hour recovery period at 30 minute intervals until 3 hours, and again at 5 hours after extubation. All data were analyzed using anova . Multiple comparisons were performed if the anova was significant. Alpha value was set at 0.05. Plasma cortisol concentrations significantly increased from time of extubation in all the treatment groups. They did not return to the baseline until 5, 2.5, 1.5, and 1.5 hours after extubation in the C, B, E, and EB groups, respectively. Isoflurane AUC was not significantly different among treatment groups. Dogs treated with EB had significantly less behavioral pain than all other groups throughout the 5‐hour recovery period. No significant difference was found between treatment groups or within treatment groups over time in BMBT, or any renal variables. This study demonstrated that (i) pre‐operative administration of E provides profound analgesia during the post‐operative period without renal or bleeding side‐effects in dogs undergoing OHE; and (ii) a combination of butorphanol–etodolac provides the best analgesic effect during the post‐operative period based on the behavioral pain score.     

Evaluation of aqueous tear production in dogs following general anesthesia

Pre- and postanesthetic Schirmer tear test (STT) values were measured in 46 dogs. All subjects had normal preanesthetic STT values (18.3 +/- 2.8 mm per min in the left eye [OS] and 18.3 +/- 3.0 mm per min in the right eye [OD]). Significant differences were found between pre- and postanesthetic STT values. Significant decreases in tear production were evident for up to 24 hours following the anesthetic event. Subject age did not significantly influence the results. Duration of anesthesia significantly affected the rate of return to preanesthetic STT values, with anesthetic events greater than two hours in duration having a prolonged effect as compared to anesthetic events less than two hours in duration. Anticholinergic administration prior to or during anesthesia further lowered postanesthetic STT values.     

Nephrotoxicity in dogs associated with methoxyflurane anesthesia and flunixin meglumine analgesia

Uremia unexpectedly developed in five dogs 24 hours after undergoing thoracotomy in a student laboratory. In all dogs general anesthesia had been maintained with methoxyflurane, muscle relaxation had been induced with gallamine, and each dog received a single intravenous dose of 1.0 mg/kg flunixin meglumine for analgesia upon termination of anesthesia. In a subsequent group of dogs undergoing an orthopedic procedure, we assessed the effects on renal function of methoxyflurane anesthesia plus oxymorphone, or of methoxyflurane or halothane anesthesia in combination with a single IM 1.0 mg/kg dose of flunixin meglumine. Significant elevations in serum urea and creatinine values, and necrosis of collecting ducts and loops of Henle, were noted only in the dogs receiving methoxyflurane and flunixin meglumine.

We conclude that the use of combination of methoxyflurane and flunixin meglumine is contraindicated in dogs.

     

Effects of preoperative administration of ketoprofen on anesthetic requirements and signs of postoperative pain in dogs undergoing elective ovariohysterectomy

OBJECTIVE: To determine the effects of preoperative administration of ketoprofen on anesthetic requirements and signs of postoperative pain in dogs undergoing elective ovariohysterectomy. DESIGN: Randomized, controlled clinical trial. ANIMALS: 22 clinically normal client-owned dogs. PROCEDURE: 60 minutes before induction of anesthesia, 11 dogs were given ketoprofen (2 mg/kg [0.9 mg/lb], i.m.), and the other 11 were given saline (0.9% NaCl) solution. Dogs were premedicated with glycopyrrolate, acepromazine, and butorphanol and anesthetized with thiopental; anesthesia was maintained with isoflurane. Ovariohysterectomy was performed by an experienced surgeon, and butorphanol was given 15 minutes before completion of the procedure. Objective behavioral scores and numerical pain scores at rest and with movement were recorded every 2 hours for 12 hours after surgery and then every 4 hours for an additional 12 hours. RESULTS: Preoperative administration of ketoprofen did not reduce the dose of thiopental required to induce anesthesia or the end-tidal concentration of isoflurane required to maintain anesthesia. Activity levels and median objective behavioral scores were significantly higher 4 and 6 hours after surgery in dogs given ketoprofen than in dogs given saline solution. However, mean numerical pain scores in dogs given ketoprofen were not significantly different from scores for dogs given saline solution at any time. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that preoperative administration of ketoprofen does not reduce anesthetic requirements in dogs undergoing elective ovariohysterectomy but may reduce signs of pain after surgery. Results also suggest that the objective behavioral score may be a more sensitive measure of acute postoperative pain than traditional numerical pain scores.