The effect of premedication on the incidence of gastrooesophageal reflux during general anaesthesia in the dog.

Gastroeosophageal reflux (GOR) has been proved to be a serious complication of general anesthesia in humans and in dogs and cats. It mainly occurs when Lower Oesophageal Sphincter (LOS) pressure is decreased. The incidence of reflux in dogs range from 13% to 56% .There are many factors which influence the occurrence of GOR such as age, sex, weight, type of surgery, premedication and general anesthesia, volume and acidity of gastric content and duration of preanaesthetic fasting. The study was divided into the clinical and the experimental part. The clinical part included dogs of physical status 1 or 2 that underwent elective surgeries. All intra-abdominal and intra-thoracic surgeries were excluded from the study. The experimental part consist of 20 beagle dogs, that underwent general anaesthesia of a total of three times each, without any surgical manipulation. All subjects included in the study, had the same preanaesthetic fasting, with the last meal given three hours before premedication at the amount of half the daily portion of canned food. All dogs had free access to water up to one hour before premedication. Premedication in clinical cases included one of the following combinations: dexmedetomidine with morphine, pethidine or butorphanol, acepromazine with morphine, pethidine or butorphanol and midazolam with morphine, pethidine or butorphanol. Anaesthesia was induced with propofol to effect and maintained with isoflurane in oxygen. A pH-meter was inserted into the oesophagus, after anaesthesia was induced, in order to observe and record the pH of the refluxate. The duration of the observations ranged from 60 to 105 min in all cases. In the experimental part, each dog underwent three anaesthetic procedures in total, with intervals of one week. Premedication included dexmedetomidine, acepromazine or midazolam. Anaesthesia was induced with propofol and maintained with isoflurane in oxygen. The pH of the oesophagus was monitored and recorded for 60 min. Results of this study reveal a 44.1% of reflux during anaesthesia. The group of acepromazine – butorphanol demonstrated the highest incidence of reflux (66.7%). In contrast, the lowest incidence of reflux is located in the acepromazine – pethidine group (26.7%). High incidence of reflux was also observed in the dexmedetomidine – butorphanol group (53.3%). All cases of GOR experienced an acidic episode of reflux, except two cases of alkaline pH. GOR is recorded to have occurred during the first 30 min of anaesthesia except of 9 cases where reflux occurred after 60 min of anaesthesia. Castration revealed a high incidence of reflux in contrast to the diagnostic procedures and the experimental cases which experienced no incidence of reflux. Age, sex, weight, and recumbency did not reveal any influence on the incidence of reflux. Preanaesthetic fasting did not influence either the pH of the refluxate or the incidence of reflux. The presence of surgical manipulations and the use of opioids as part of the premedication appear to increase the incidence of reflux in dogs during anaesthesia.Γαστροοισοφαγική παλινδρόμηση (ΓΟΠ) ονομάζεται η παλινδρόμηση γαστρικού περιεχομένου διαμέσου του οπίσθιου οισοφαγικού σφιγκτήρα (ΟΟΣ) προς τον αυλό του οισοφάγου. Η συχνότητα εμφάνισης της ΓΟΠ στο σκύλο κατά τη διάρκεια της γενικής αναισθησίας κυμαίνεται από 13% έως 56% σύμφωνα με τη διεθνή βιβλιογραφία. Στους παράγοντες που προδιαθέτουν στην εμφάνιση της ΓΟΠ συγκαταλέγονται η γενική αναισθησία, οι χειρουργικοί χειρισμοί, η προεγχειρητική νηστεία, η θέση κατάκλισης, η ηλικία, το βάρος, το φύλο καθώς και διάφορες παθολογικές καταστάσεις που πιθανόν να συνυπάρχουν. Η μελέτη χωρίστηκε σε δύο μέρη. Το πρώτο μέρος περιελάμβανε κλινικά περιστατικά τα οποία υποβάλλονταν σε μη ενδοκοιλιακές ή μη ενδοθωρακικές επεμβάσεις. Το δεύτερο μέρος περιελάμβανε σκύλους της φυλής beagle που υποβάλλονται σε γενική αναισθησία χωρίς την πρόκληση χειρουργικού ερεθισμού. Όλα τα ζώα υποβλήθηκαν σε τρίωρη νηστεία πριν την έναρξη της προαναισθητικής αγωγής, με το τελευταίο γεύμα τους να περιλαμβάνει τη μισή ημερήσια ποσότητα κονσερβοποιημένης τροφής. Η πρόσβαση σε νερό ήταν ελεύθερη έως και μία ώρα από την έναρξη των πειραματισμών. Στα κλινικά περιστατικά χορηγήθηκαν, ως προαναισθητική αγωγή ένας από τους παρακάτω συνδυασμούς: δεξμεδετομιδίνη ή ακετυλοπρομαζίνη ή μιδαζολάμη σε συνδυασμό με ένα από τα παρακάτω οπιοειδή, μορφίνη ή πεθιδίνη ή βουτορφανόλη. Η εγκατάσταση της γενικής αναισθησίας έγινε σε όλα τα ζώα με προποφόλη και η διατήρηση με ισοφλουράνιο σε οξυγόνο. Μετά την εγκατάσταση της γενικής αναισθησίας τοποθετήθηκε ειδική συσκευή καταμέτρησης του pH του οισοφάγου. Η παρακολούθηση του pH του οισοφάγου και η καταγραφή του διήρκεσε από 60 λεπτά έως και 105 λεπτά σε όλες τις περιπτώσεις. Στο πειραματικό μέρος 20 σκύλοι φυλής beagle υποβλήθηκαν σε τρεις διαφορετικές αναισθησίες με μεσοδιάστημα μίας εβδομάδας από την κάθε αναισθησία και με μόνη διαφορά την προαναισθητική αγωγή που χορηγήθηκε. Σε όλα τα ζώα χορηγήθηκε προαναισθητικά δεξμεδετομιδίνη ή ακετυλοπρομαζίνη ή μιδαζολάμη ενώ η υπόλοιπη διαδικασία της γενικής αναισθησίας ήταν ίδια με το κλινικό μέρος. Η μετρήσεις του pH του οισοφάγου διαρκούσαν 60 λεπτά και σε κανένα ζώο δεν ασκήθηκε οποιοσδήποτε χειρουργικός ερεθισμός. Τα αποτελέσματα αυτής της έρευνας δείχνουν ότι το 44,1% το ζώων στα οποία χορηγήθηκαν οπιοειδή στην προαναισθητική αγωγή παρουσίασαν ΓΟΠ. Το υψηλότερο ποσοστό παλινδρόμησης καταγράφηκε στην ομάδα της ακετυλοπρομαζίνης - βουτορφανόλης (66,7%), ενώ το χαμηλότερο ποσοστό παλινδρόμησης παρουσίασε η ομάδα της ακετυλοπρομαζίνης – πεθιδίνης (26,7%). Όλα τα περιστατικά που εμφάνισαν ΓΟΠ είχαν όξινο pH αναγόμενου περιεχομένου, εκτός από δυο περιστατικά που είχαν αλκαλικό. Ο χρόνος εμφάνισης ΓΟΠ καταγράφεται στα πρώτα 30 λεπτά μετά την έναρξη της γενικής αναισθησίας, με μόλις 9/117 περιστατικά να εμφανίζουν ΓΟΠ μετά το πέρας το 60 λεπτών. Οι ορχεκτομές φαίνεται να εμφανίζουν αυξημένα ποσοστά ΓΟΠ σε σχέση με τα διαγνωστικά περιστατικά και τα πειραματικά περιστατικά τα οποία δεν παρουσίασαν κανένα περιστατικό παλινδρόμησης. Το φύλο, το βάρος, η ηλικία και η πλευρά κατάκλισης δεν φαίνεται να επηρεάζει τη συχνότητα εμφάνισης της ΓΟΠ. Η προεγχειρητική νηστεία δεν φαίνεται να επηρέασε τη συχνότητα εμφάνισης ΓΟΠ ούτε και το pH του αναγόμενου περιεχομένου. Συμπερασματικά, φαίνεται ότι η χρήση των οπιοειδών στην προαναισθητική αγωγή και οι χειρουργικοί χειρισμοί αυξάνουν τη συχνότητα εμφάνισης τη ΓΟΠ

Factors Affecting Intraoperative Gastro-Oesophageal Reflux in Dogs and Cats

In animals, gastro-oesophageal reflux (GOR) may occur during anaesthesia, and it can lead to severe consequences such as oesophagitis and oesophageal stricture. This systematic review investigates the effect of fasting duration and anaesthetic and nonanaesthetic drugs on GOR in dogs and cats during general anaesthesia. Fifteen clinical studies met the inclusion criteria in this systematic review. In thirteen studies the population was dogs, while in two studies the population was cats. In the meta-analysis, seven studies were included. Four studies on the effect of fasting duration on GOR in dogs were included in the meta-analysis. In total, 191 dogs had a fasting duration less than 5 h, while 311 dogs had a fasting duration more than 5 h. The heterogeneity of the studies was high and statistically significant (p = 0.0002, I2 = 85%), but the overall effect was statistically nonsignificant (p = 0.82, odds ratio = 0.81, 95% CI 0.15, 4.26), in favour of the low fasting duration (p = 0.13, I2 = 52%) and the overall effect was statistically nonsignificant (p = 0.24). The low number of studies and the diverse factors affecting the incidence of reflux prevented us from reaching valuable conclusions on the risk factors for GOR

The Effect of Premedication on the Incidence of Gastroesophageal Reflux in 270 Dogs Undergoing General Anesthesia

The aim of this prospective, non-randomized study was to evaluate the effect of nine different premedication medications on the incidence of gastroesophageal reflux (GOR) in anesthetized dogs. Two hundred and seventy dogs undergoing non-intrathoracic, non-intrabdominal elective surgeries or invasive diagnostic procedures were included in the study, and were allocated into nine groups (30 dogs/group) defined by the type of premedication administered. Premedication consisted of dexmedetomidine with either morphine, pethidine or butorphanol, acepromazine with either one of the three opioids or midazolam with one of the above-mentioned opioids. Anesthesia was induced with propofol and maintained with isoflurane in oxygen. Esophageal pH was measured with the use of a pH-meter electrode and a pH-value less than 4 and over 7.5 was considered to be GOR. The study revealed that 119/270 (44.1%) dogs experienced a reflux episode during anesthesia. The incidence of reflux did not differ among groups (p = 0.117). In group AB the dogs refluxed within 10 min of the beginning of pH-measurements, in comparison with group DB in which dogs refluxed within 30 min (p = 0.029). Invasive diagnostic procedures had a lower incidence of GOR in comparison to castrations (p = 0.09). The outcome of the study suggests that none of the opioids used increased the incidence of GOR in anesthetized dogs

First-Intention Incisional Wound Healing in Dogs and Cats: A Controlled Trial of Dermapliq and Manuka Honey

This study aimed to compare incisional wound healing in cats and dogs after the topical application of Μanuka honey and a new medical device, Dermapliq. Comparisons were made between each treatment and control, between the two treatments, and between dogs and cats. Twelve cats and twelve dogs were included in this study, and the impact of the two substances was examined through cosmetic, clinical, ultrasonographical, and histological evaluation. The use of Dermapliq in first-intention wound healing achieved a significantly better cosmetic evaluation score and better total clinical score at days 20–41, compared to the control, in both dogs and cats. The ultrasonographically estimated wound area was smaller with Dermapliq compared to the control. Wounds treated with Dermapliq showed histologically less inflammation compared to the control. The use of Manuka honey did not show a significantly better cosmetic score compared to the control. Skin thickening was significantly higher after using Manuka honey compared to the control and so was the total clinical score. However, the median wound area, as was evaluated ultrasonographically, was significantly smaller when wounds were treated with Manuka honey, the difference being more apparent in dogs. Dermapliq was proven to be a better choice in achieving favorable wound healing than Manuka honey in dogs and cats in first-intention healing. In our study, cats had a statistically better cosmetic score and less skin thickening and scar width compared to dogs. Histologically, cats showed significantly less edema, higher inflammation and angiogenesis scores, and lower fibroblast and epidermis thickening scores when compared to dogs

Efficacy of rifampicin in the treatment of experimental acute canine monocytic ehrlichiosis

To assess the efficacy of rifampicin in achieving clinical and haematological recovery and clearing infection in dogs with experimentally induced acute monocytic ehrlichiosis. Five Ehrlichia canis-infected Beagle dogs were treated with rifampicin (10 mg/kg/24 h orally for 3 weeks), nine E. canis-infected dogs received no treatment (infected untreated dogs) and two dogs served as uninfected controls. Clinical score, platelet counts, immunofluorescent antibody titres and PCR detection of E. canis-specific DNA in blood, bone marrow and spleen aspirates were evaluated on post-inoculation days 21 (start of rifampicin), 42 (end of rifampicin) and 98 (end of the study). By day 21 post-inoculation, all infected dogs became clinically ill and thrombocytopenic, seroconverted and were PCR positive in at least one tissue. Clinical scores and antibody titres did not differ between the treated and infected untreated dogs throughout the study. The rifampicin-treated dogs experienced an earlier resolution of their thrombocytopenia (KaplanMeier survival plot, P0.048), and the median platelet counts were significantly higher in the treated compared with the infected untreated dogs on post-inoculation days 42 (P0.0233) and 98 (P0.0195). At the end of the study, three treated and six untreated infected dogs remained PCR positive in one tissue each. The rifampicin treatment regimen applied in this study hastened haematological recovery, but was inconsistent in eliminating the acute E. canis infection