Faculty of Veterinary Medicine University of Zagreb
Abstract
Ruminants are generally not considered good subjects for general anaesthesia mainly because of the hazards of regurgitation and inhalation of ruminal contents or saliva into the lungs if the airway is left unprotected. Thus, regional anaesthesia produced by perineural or epidural injections of anaesthetic agents are most frequently employed in these species. The following study was carried out to compare directly the time of onset and duration of analgesia produced by a lidocaine-MgSO4 combination with that produced by lidocaine-distilled water administration in the epidural space of goats. Seven healthy adult (2 ± 0.5 years of age) native goats (49 ± 3 kg) were selected for this study. Caudal epidural anesthesia was produced in all goats by 2% lidocaine (1 mL/7 kg) with 1 mL distilled water and two weeks later repeated by 2% lidocaine (1 mL/7 kg) with 1 mL of 10% MgSO4. Time of onset, duration, standing and cranial spread of analgesia were recorded. Heart rate, respiratory rate and body temperature were recorded at 0 minutes prior to epidural administrations of each treatments as base line values and at 10, 30, 45 and 60 minutes after the epidural administration of each treatments. Statistical analysis included the paired Student’s t-test and ANOVA (SPSS, soft ware of windows). P<0.05 was considered as a significant level. A significant difference (P<0.05) was noted for the onset of analgesia between lidocaine-distilled water (2.38 ± 0.38 min) and lidocaine-MgSO4 (3.71 ± 0.38 min). Lidocaine-MgSO4 produced analgesia of significantly longer duration (171.85 ± 8.07 min) than that of lidocaine-distilled water (61.42 ± 6.39 min). There were no significant differences in standing time between the two groups. There were no significant differences in HR, RR, and body temperature in comparison with the base line values in the lidocaine-distilled water and lidocaine-MgSO4 groups. Using this combination, long duration obstetrical and surgical procedures could commence relatively soon after epidural injection and could be completed without re-administration of the anesthetic agent.Preživači općenito nisu pogodni za opću anesteziju većinom zbog opasnosti od regurgitacije i inhalacije buražna sadržaja ili sline u pluća, ako su im zračni prohodi nezaštićeni. Zbog toga se u njih najčešće primjenjuje perineuralna ili epiduralna anestezija. Ovo istraživanje je provedeno radi izravne usporedbe nastupa i trajanja analgezije postignute primjenom lidokaina i magnezijeva sulfata te lidokaina i destilirane vode u epiduralni prostor u koza. Sedam zdravih odraslih koza (u dobi od 2 ± 0,5 godina) tjelesne mase od 49 ± 3 kg odabrano je za ovo istraživanje. U svih je provedena kaudalna epiduralna anestezija 2%-tnim lidokainom (1 mL/7 kg) i jednim mililitrom destilirane vode. Dva tjedna poslije, epiduralna anestezija bila je ponovljena 2%-tnim lidokainom (1 mL/7 kg) i jednim mililitrom 10%-tnog magnezijeva sulfata. Promatrano je vrijeme nastupa anestezije, njezino trajanje, postojanost i kranijalno širenje. Frekvencija bila i disanja te tjelesna temperatura izmjereni su prije davanja anestezije kao bazalne vrijednosti, a zatim 10, 30, 45 i 60 minuta nakon epiduralne injekcije. Rezultati su bili statistički obrađeni Student t-testom i ANOVA testom. P<0,05 smatran je značajnom razinom. Značajna razlika (P<0,05) bila je zabilježena u vremenu nastupa analgezije postignute lidokainom i destiliranom vodom (2,38 ± 0,38 min) te lidokainom i magnezijevim sulfatom (3,71 ± 0,38 min). Analgezija postignuta lidokainom i magnezijevim sulfatom trajala je znatno duže (171,85 ± 8,07 min) od one postignute lidokain-destiliranom vodom (61,42 ± 6,39 min). Nije ustanovljena statistički značajna razlika za frekvenciju bila, disanja i tjelesnu temperaturu u odnosu na bazalne vrijednosti u obih skupina. Primjenom kombinacije lidokain-magnezijev sulfat dugotrajni porodnički i kirurški zahvati mogu započeti relativno brzo nakon epiduralne injekcije te se mogu završiti bez ponovljene primjene anestetika
