Contemporary perspectives on perioperative fluid therapy.

The primary purpose of perioperative IV fluid administration is to preserve tissue perfusion by maintaining or restoring the effective circulating intravascular volume. Fluids are drugs that produce beneficial or harmful effects dependent upon their composition, osmotic potential, kinetics, and dose. Appropriate dosing requires an understanding of body fluid compartments, fluid balance, and the administered fluids' behavior in the body. Anesthetic drugs and general anesthesia produce CNS, neuroendocrine, and macro-/microvascular hemodynamic effects. These effects modulate the response to IV fluid administration and promote interstitial fluid accumulation, third-space fluid loss, and fluid overload. This narrative review discusses current knowledge regarding anesthesia-associated physiologic and IV fluid kinetic changes that influence the efficacy of IV fluid administration during the intraoperative period. A rationale for intraoperative fluid dosing that addresses intraoperative hypotension, blood loss, and practices that promote fluid overload is provided. Intraoperative IV fluid administration should be individualized and monitored by dynamic goal-directed methods that evaluate fluid responsiveness.

Serum C-reactive protein and iron levels following gonadectomy are not modified by perioperative administration of robenacoxib to dogs.

The aim of this study was to evaluate the perioperative effects of robenacoxib on serum C-reactive protein (CRP) and iron concentrations in dogs undergoing gonadectomy. In a prospective, blinded, controlled clinical trial, 60 healthy dogs were randomly assigned to receive preoperative subcutaneous injection of either robenacoxib [2 mg/kg body weight (BW)], meloxicam (0.2 mg/kg BW), or saline (0.04 mL/kg BW), followed by oral administration over 72 h (robenacoxib: 2 to 4 mg/kg BW; meloxicam: 0.1 mg/kg BW; saline: gelatin capsules). Blood samples were taken before surgery and 12, 24, 48, 72 h, and 7 d after surgery. Pain scores were assessed via the short-form Glasgow Composite Pain Scale over 72 h postoperatively. C-reactive protein (CRP) and iron serum levels increased and decreased (P < 0.01, both), respectively, after surgery and returned to baseline within 1 wk. No differences were observed among treatments (P > 0.05) or based on surgery/gender (P > 0.05). Pain assessment revealed a higher incidence of treatment failure in saline (6 females versus 2 and 1 female in robenacoxib and meloxicam, respectively). In conclusion, robenacoxib and meloxicam had no influence on postoperative CRP or iron in dogs, which suggests that these nonsteroidal anti-inflammatory drugs (NSAIDs) do not have a relevant effect on these biomarkers.

Le but de cette étude était d'évaluer les effets périopératoires du robenacoxib sur les concentrations sériques de protéine C réactive (CRP) et de fer chez des chiens subissant une gonadectomie. Dans un essai clinique prospectif, en aveugle et contrôlé, 60 chiens en bonne santé ont été randomisés pour recevoir une injection sous-cutanée préopératoire de robenacoxib [2 mg/kg de poids corporel (PC)], de méloxicam (0,2 mg/kg de poids corporel) ou de solution saline (0,04 mL/kg de poids corporel), suivie d'une administration orale pendant 72 h (robenacoxib : 2 à 4 mg/kg de poids corporel; méloxicam : 0,1 mg/kg de poids corporel; saline : gélules). Des échantillons de sang ont été prélevés avant la chirurgie et 12, 24, 48, 72 h et 7 jours après la chirurgie. Les pointages de douleur ont été évalués via l'échelle abrégée Glasgow Composite Pain Scale sur 72 h après l'opération. Les taux sériques de CRP et de fer ont augmenté et diminué (P < 0,01, les deux), respectivement, après la chirurgie et sont revenus à la valeur de base en 1 semaine. Aucune différence n'a été observée entre les traitements (P > 0,05) ou en fonction de la chirurgie/du sexe (P > 0,05). L'évaluation de la douleur a révélé une incidence plus élevée d'échec du traitement avec la saline (6 femelles contre 2 et 1 femelles pour le robenacoxib et le méloxicam, respectivement). En conclusion, le robenacoxib et le méloxicam n'ont eu aucune influence sur la CRP ou le fer postopératoire chez le chien, ce qui suggère que ces anti-inflammatoires non stéroïdiens (AINS) n'ont pas d'effet pertinent sur ces biomarqueurs.(Traduit par Docteur Serge Messier).

Psittacine Sedation and Anesthesia.

Successful management of sedation/anesthesia of psittacine species relies on familiarity with their specific anatomy and physiology, and detailed knowledge of the recent advancements in applied pharmacology of the anesthetics and perianesthetic monitoring of cardiovascular and respiratory functions. Each sedation/anesthetic plan should be patient-specific, developed based on preexisting conditions, size, species, age, and estimated risk. Other key factors to improve safety, quality of perioperative care, and client satisfaction are anticipation of complications, extension of close monitoring to the recovery phase, multimodal analgesic approach, stress prevention/reduction, and transparent communication with the owner.

Rehabilitation Therapy in Perioperative Pain Management.

Physical agent modalities can be effective in the perioperative period for controlling pain and inflammation. This article presents research-based evidence to support the use of these modalities in pain management and to reduce the use of pain medications, including opioids. The mechanism of action, applications, contraindications, and adverse effects of cryotherapy, pulsed electromagnetic field therapy, transcutaneous electrical nerve stimulation, and laser therapy are reviewed. Incorporation of 1 or more of these therapies in anesthesia pain management protocols can improve outcomes and reduce potential drug side effects.

Factors associated with dehiscence and mortality rates following gastrointestinal surgery in dogs.

OBJECTIVE: To identify factors associated with dehiscence and mortality rates following gastrointestinal surgery in dogs. ANIMALS: 170 client-owned dogs that underwent gastrointestinal surgery from 2010 to 2016. PROCEDURES: Medical records of all included dogs were reviewed to collect information on preoperative (breed, sex, age, body weight, American Society of Anesthesiologists [ASA] physical status classification, emergency status, and plasma lactate concentration), intraoperative (indication for surgery, type of surgery, and whether bacterial peritonitis was identified), and postoperative (development of dehiscence and survival status at 2 weeks after surgery) factors. Preoperative and intraoperative factors were evaluated for associations among each other and with postoperative factors. RESULTS: Univariate analyses revealed that preoperative plasma lactate concentration increased with increasing ASA status, and lactate concentrations were significantly higher for nonsurvivors (mean ± SD, 4.6 ± 3.7 mmol/L) than for survivors (2.4 ± 1.7 mmol/L). Multivariate analysis controlling for age, body weight, and plasma lactate concentration revealed that dogs with an ASA status ≥ 3 were more likely to develop dehiscence after gastrointestinal surgery than were dogs with a lower ASA status (OR, 17.77; 95% confidence interval, 2.17 to 144.06). Multivariate analysis also revealed that dogs with an ASA status ≥ 3 or high lactate concentration were less likely to survive than were other dogs. CONCLUSIONS AND CLINICAL RELEVANCE: These findings regarding ASA status and preoperative plasma lactate concentration and their associations with outcome may help clinicians to determine and provide optimal perioperative care to dogs requiring gastrointestinal surgery as well as to inform owners about prognosis.

Randomised trial of perioperative tramadol for canine sterilisation pain management.

Surgical sterilisation to manage free-roaming dog populations is widely used in many countries. However, few studies have examined optimal postoperative pain management regimens at low-resource, high-throughput veterinary clinics. The aim of this study was to examine the efficacy of two intravenous analgesic regimens, preoperative administration of meloxicam and tramadol, or meloxicam alone, in free-roaming dogs undergoing sterilisation. A total of 125 dogs were included, with 64 dogs in the meloxicam-tramadol arm and 61 dogs in the meloxicam-only arm in a non-inferiority study design. Pain levels in sterilisation surgery patients were assessed at four time points after surgery using the Colorado State University Canine Acute Pain Scale, a Visual Analogue Scale and a modified version of the Glasgow Composite Measure Pain Scale - Short Form. Non-inferiority was supported for each of the main scoring outcomes using non-inferiority margins of 0.5, 5 and 0.8, respectively. One dog from the meloxicam-tramadol group and four dogs in the meloxicam-only arm required rescue analgesia, with no difference between groups (P=0.21).The study demonstrated that meloxicam was effective in controlling postoperative pain in a high proportion of dogs. The addition of tramadol alongside meloxicam treatment was not found to be of clinical benefit.

Anaesthesia of brachycephalic dogs.

Brachycephalic breeds of dog have grown in popularity in the UK and so form an increasing proportion of cases requiring anaesthesia. These breeds are predisposed to several conditions, notably brachycephalic obstructive airway syndrome and gastro-oesophageal reflux, that have important implications for anaesthetic management and carry high risk for complications. This review incorporates peer-reviewed veterinary literature with clinical experience in a discussion on perioperative management of brachycephalic dogs. We focus on preoperative identification of common concurrent conditions, practical strategies for reducing anaesthetic risk and improving postoperative management. Comparisons of brachycephalic obstructive airway syndrome with the human condition of obstructive sleep apnoea are included where appropriate.

A prospective, randomized, double-blinded, placebo-controlled clinical study on postoperative antibiotherapy in 150 arthroscopy-assisted tibial plateau leveling osteotomies in dogs.

OBJECTIVE: To determine the influence of a 7-day course of postoperative antibiotherapy (cefpodoxime) on surgical site infections (SSI) after tibial plateau leveling osteotomy (TPLO). STUDY DESIGN: Prospective, randomized, double-blinded, placebo-controlled clinical study. SAMPLE POPULATION: One hundred fifty client-owned dogs, with consent. METHODS: Dogs undergoing arthroscopy-assisted TPLO were randomly assigned to 1 of 2 groups, the placebo group receiving perioperative cefazolin and 7 days of placebo medication after surgery or the treatment group receiving perioperative cefazolin and 7 days of postoperative cefpodoxime. Twenty-seven factors were analyzed for association with SSI by using univariate analysis, Fisher's exact test, or Wilcoxon rank-sum test. RESULTS: SSI rates did not differ (P = .34) between the placebo group (17%; 95% confidence level [CL] 7.94%-26.43%) and the treatment group (11% SSI; 95% CL 3.98%-18.88%). The probability that > 23% of dogs would benefit from postoperative antibiotherapy was less than 5%. The only association between the factors tested in this study and SSI involved the body weight (kg), with each 1 unit increase in kilogram weight increasing the odds of developing an SSI by 4.7%. CONCLUSION: Although the wide CL may be consistent with a type II error, a 7-day course of cefpodoxime after arthroscopy-assisted TPLO did not influence postoperative SSI in the population tested here. In addition, only a small proportion of dogs would benefit from postoperative antibiotherapy under the conditions of our study. CLINICAL SIGNIFICANCE: These results should prompt surgeons to reconsider systematic antibiotherapy after TPLO and justify additional studies to determine whether dogs predisposed to infection could benefit from such an approach.

Refinement of Perioperative Feeding in a Mouse Model of Vertical Sleeve Gastrectomy.

Provision of liquid enteral nutrition (LEN) during the perioperative period is standard practice for rodents undergoing bariatric surgery, yet these diets are associated with several challenges, including coagulation of the liquid diet within the delivery system and decreased postoperative consumption. We investigated the use of a commercially available high-calorie dietary gel supplement (DG) as an alternative food source for mice during the perioperative period. C57BL/6J male mice were fed high-fat diet for 8 to 10 wk prior to surgery. The study groups were: vertical sleeve gastrectomy (VSG) +DG, VSG+LEN, sham surgery+DG, and sham+LEN. Food and water intakes, body weight, and body fat composition was monitored throughout the study. Mice that received DG lost significantly more weight preoperatively than those fed LEN. However, during the postoperative period, body weight, body fat composition, and water and caloric intake were similar among all experimental diet groups. Three mice in the VSG+LEN group were euthanized due to clinical illness during the course of the study. In summary, feeding a high-calorie DG to mice undergoing VSG surgery is a viable alternative to LEN, given that DG does not significantly affect the surgical model of weight loss or result in adverse clinical outcomes. We recommend additional metabolic characterization of DG supplementation to ensure that this novel diet does not confound specific research goals in the murine VSG model.

Surgical Site Infection Rate after Hemilaminectomy and Laminectomy in Dogs without Perioperative Antibiotic Therapy.

OBJECTIVE: The aim of this study was to retrospectively review the surgical site infection (SSI) rate in dogs undergoing laminectomies without perioperative antibiotics, and compare those data with the expected infection rate for clean surgical wounds in dogs undergoing similar procedures. METHODS: This was a retrospective single-centre study composed of dogs that underwent hemilaminectomies or laminectomies for thoracolumbar disc herniation or lumbosacral disease during a 2-year period (during 2015 and 2016). All incisional complications within 30 days were recorded and divided into superficial, deep or organ/space infections. Those dogs that received perioperative or postoperative antibiotics due to non-related comorbidities and those with incomplete medical records during the study period were excluded. RESULTS: Of 221 consecutive hemilaminectomy and laminectomy procedures, 154 were included in this research study. One superficial wound infection was recorded and treated with antimicrobials. Overall, the SSI rate was 0.6%, while the expected SSI rate in clean operative wounds in dogs and cats is 2.0 to 4.8%. The SSI rate in human spinal surgery is 0.7 to 4.3%. CLINICAL SIGNIFICANCE: Considering the low incidence of SSI in our study group, the routine use of perioperative antibiotic prophylaxis in dogs undergoing laminectomy procedures should be reconsidered to help address the global problem of bacterial resistance.

Incidence of blood transfusion requirement and factors associated with transfusion following liver lobectomy in dogs and cats: 72 cases (2007-2015).

OBJECTIVE To determine the incidence of blood transfusion, mortality rate, and factors associated with transfusion in dogs and cats undergoing liver lobectomy. DESIGN Retrospective case series. ANIMALS 63 client-owned dogs and 9-client owned cats that underwent liver lobectomy at a specialty veterinary practice from August 2007 through June 2015. PROCEDURES Medical records were reviewed and data extracted regarding dog and cat signalment, hematologic test results before and after surgery, surgical method, number and identity of lobes removed, concurrent surgical procedures, hemoabdomen detected during surgery, incidence of blood transfusion, and survival to hospital discharge (for calculation of mortality rate). Variables were compared between patients that did and did not require transfusion. RESULTS 11 of 63 (17%) dogs and 4 of 9 cats required a blood transfusion. Mortality rate was 8% for dogs and 22% for cats. Pre- and postoperative PCV and plasma total solids concentration were significantly lower and mortality rate significantly higher in dogs requiring transfusion than in dogs not requiring transfusion. Postoperative PCV was significantly lower in cats requiring transfusion than in cats not requiring transfusion. No significant differences in any other variable were identified between dogs and cats requiring versus not requiring transfusion. CONCLUSIONS AND CLINICAL RELEVANCE Dogs and cats undergoing liver lobectomy had a high requirement for blood transfusion, and a higher requirement for transfusion should be anticipated in dogs with perioperative anemia and cats with postoperative anemia. Veterinarians performing liver lobectomies in dogs and cats should have blood products readily available.

Perioperative Fluid Therapy.

Anesthesia can lead to pathophysiologic changes that dramatically alter the fluid balance of the body compartments and the intravascular space. Fluid administration can be monitored and evaluated using static and dynamic indexes. Guidelines for fluid rates during anesthesia begin with 3 mL/kg/h in cats and 5 mL/kg/h in dogs. If at all possible, patients should be stabilized and electrolyte disturbances should be corrected before general anesthesia.

Impact of Stroke Therapy Academic Industry Roundtable (STAIR) Guidelines on Peri-Anesthesia Care for Rat Models of Stroke: A Meta-Analysis Comparing the Years 2005 and 2015.

Numerous studies using rats in stroke models have failed to translate into successful clinical trials in humans. The Stroke Therapy Academic Industry Roundtable (STAIR) has produced guidelines on the rodent stroke model for preclinical trials in order to promote the successful translation of animal to human studies. These guidelines also underline the importance of anaesthetic and monitoring techniques. The aim of this literature review is to document whether anaesthesia protocols (i.e., choice of agents, mode of ventilation, physiological support and monitoring) have been amended since the publication of the STAIR guidelines in 2009. A number of articles describing the use of a stroke model in adult rats from the years 2005 and 2015 were randomly selected from the PubMed database and analysed for the following parameters: country where the study was performed, strain of rats used, technique of stroke induction, anaesthetic agent for induction and maintenance, mode of intubation and ventilation, monitoring techniques, control of body temperature, vascular accesses, and administration of intravenous fluids and analgesics. For each parameter (stroke, induction, maintenance, monitoring), exact chi-square tests were used to determine whether or not proportions were significantly different across year and p values were corrected for multiple comparisons. An exact p-test was used for each parameter to compare the frequency distribution of each value followed by a Bonferroni test. The level of significant set at < 0.05. Results show that there were very few differences in the anaesthetic and monitoring techniques used between 2005 and 2015. In 2015, significantly more studies were performed in China and significantly fewer studies used isoflurane and nitrous oxide. The most striking finding is that the vast majority of all the studies from both 2005 and 2015 did not report the use of ventilation; measurement of blood gases, end-tidal carbon dioxide concentration, or blood pressure; or administration of intravenous fluids or analgesics. The review of articles published in 2015 showed that the STAIR guidelines appear to have had no effect on the anaesthetic and monitoring techniques in rats undergoing experimental stroke induction, despite the publication of said guidelines in 2009.

Effect of pulse width on transesophageal atrial pacing in dogs.

OBJECTIVE: To determine the impact of stimulus pulse width (PW) on pacing threshold (PT), zone of capture (ZOC) and extraneous muscular stimulation (EMS). STUDY DESIGN: Experimental trial in client-owned dogs. ANIMALS: Seventeen dogs, median weight 16.1 kg (interquartile range: 11.4-21.5). METHODS: Transesophageal atrial pacing (TAP) involved a 6 Fr pacing catheter inserted trans-orally into the esophagus to a position aboral to the heart in anesthetized dogs. The catheter was slowly withdrawn until atrial pacing was noted on an electrocardiogram. The catheter was withdrawn in 1 cm increments until TAP could not be achieved. PTs were recorded at each pacing site using PWs of 10.0, 5.0, 2.0 and 1.8 ms, always in that order. RESULTS: The overall lowest mean PTs for all dogs were 6 ± 3 mA, 9 ± 4 mA, 11 ± 5 mA and 13 ± 5 mA at PWs of 10.0, 5.0, 2.0 and 1.8 ms, respectively. A significant decrease in overall minimum PT was noted using a PW of 10.0 ms compared with either 2.0 or 1.8 ms (p = 0.043 and p = 0.001, respectively) and pacing using 5.0 ms compared with 1.8 ms (p = 0.028). A significant increase in ZOC was noted using a PW of 10.0 ms compared with PWs of 5.0, 2.0 and 1.8 ms (p = 0.0047, p = 0.0006 and p = 0.0003, respectively), using a PW of 5.0 ms compared with PWs of 2.0 and 1.8 ms (p = 0.0011 and p = 0.0003, respectively) and using a PW of 2.0 compared with one of 1.8 ms (p = 0.0084). CONCLUSIONS AND CLINICAL RELEVANCE: Use of 10.0 or 5.0 ms PW to perform TAP minimized the power required to pace the atria, while a PW of 10.0 ms maximized the size of the ZOC.

Updates in Perioperative Care: Ideas from the Human Field.

The article focuses mainly on appropriate patient preparation for an anesthetic episode. Special attention is given to evaluate the environmental situation for optimal adjustment to reduce stress before the anesthetic event. During the anesthetic event, special attention must be paid regarding monitoring and, evaluating the patient during and after the anesthetic episode.

Nursing Care: Care of the Perioperative Patient.

This article provides a general overview of nursing care principles including an approach to developing a nursing care plan using the nursing process as its foundation. The nursing process is a problem-solving approach used in planning patient care. This article also focuses on nursing care as it pertains to the respiratory, cardiovascular, and renal systems (fluid balance) as well as care of the recumbent patient. Knowledge of nursing care techniques and risk factors for complications puts the care provider in a position of being proactive rather than reactive to patient care needs.

Oxygenation and Ventilation.

Perioperative complications commonly include oxygenation and ventilation abnormalities. The best outcome is associated with prevention. Ventilation impairment may be due to either neurologic compromise such as cervical intervertebral disk disease or severe parenchymal disease, while oxygenation failure may result from either the underlying disease or severe complications such as aspiration pneumonia, volume overload, pulmonary thromboembolism, or acute respiratory distress syndrome. This article reviews the approach to the patient with perioperative complications and provides recommendations on the management approach.

Outcome and Prognostic Indicators in Cats Undergoing Splenectomy for Splenic Mast Cell Tumors.

This was a multi-institutional retrospective study evaluating the outcome and clinical parameters associated with the postoperative prognosis of 36 cats with splenic mast cell tumors treated with splenectomy. Clinical parameters reviewed included signalment, clinical history, results of staging tests, surgical variables, administration of blood products, presence of metastasis, postoperative complications, administration of chemotherapy postoperatively, chemotherapy protocol, and response to chemotherapy. Overall median survival time was 390 days (range, 2-1737 days). Administration of a blood product (P < .0001), metastasis to a regional lymph node (P = .022), and evidence of either concurrent or historical neoplasia (P = .037) were negatively associated with survival. Response to chemotherapy (P = .0008) was associated with an improved median survival time. Larger-scale prospective studies evaluating different chemotherapy protocols are required to elucidate the discrepancy between lack of survival benefit with administration of chemotherapy and improvement in survival time with positive response to chemotherapy.

Perioperative Blood Pressure Control and Management.

Blood pressure monitoring and management is a vital part of the perianesthetic period. Disturbances in blood pressure, especially hypotension, can have significant impacts on the well-being of small animal patients. There are a variety of mechanisms present to control blood pressure, including ultra-short-, short-, and long-term mechanisms. Several conditions can contribute to decreased blood pressure, including anesthetics, tension pneumothorax, intermittent positive pressure ventilation, hypoxemia, hypercapnia, surgical positioning, and abdominal distension. If hypotension is encountered, the initial response is to provide appropriate fluid therapy. If this is inadequate, other interventions can be used to increase blood pressure and thereby increase perfusion.