- Email: [email protected]
CLINICAL OBSERVATIONS ON THE INTRA-OPERATIVE USE OF XYLAZINE IN THIOPENTONE ANAESTHESIA IN THE DOG
Proceedings of the 4th International ConeTess of Veterinarv Anaesthesia
CLINICAL OBSERVATIONS ON THE INTRA-OPERATIVE USE OF XYLAZINE IN THIOPENTONE ANAE!3THESLA IN THE DOG J.I. Cruz. Surgical T e a c h Unit, Veterinary Faculty, Zaragoza, Spain Introduction Xylazine is used as a preanaesthetic drug in the dog, either on its own or in combination with ketamine hydrochloride (Hall and Clarke, 1983). Its use has also been described in combination with diazepam, phenothiazine derivatives or guaifenesin (Benson et al., 1985; Hatch and Wilson, 1988; Clark et al., 1982). The use of xylazine as a pre-medicant in combination with barbiturates has also been reported (Moye, 1973; Hsu, 1985) but the intra-operative use of xylazine is not so well recognised. This study was carried out to assess the use of incremental doses of xylazine given intravenously during a variety of surgical procedures in dogs where inhalation techniques and opioid analgesics were not available and the only anaesthetic agent used was thiopentone sodium.
0.05U.1 mg/kg was given intramuscular-
ly2.2. Atropine sulphate. 0.04-0.2 mg/kg was
injected with the propionylpromazine or immediately afterwards but not if tachycardia was diagnosed previously or if h e dog was under 4 kg body weight and so consequently had a high heart rate. 3. Induction This took place 30 minutes after premedication. "hiopentone sodium (Penthotal, Abbott Laboratories.) 10 mg/kg as a 25%, 1.66% or 1.25% solution was injected by slow intravenous injection. 4. Maintenance For this, the animals were divided into two groups: Group 1: Maintenance by incremental doses of thiopentone, 13 mg every 12.5 minutes (24 dogs). Group 2. Maintenance by incremental doses of thiopentone, 40 mg every 20 minutes or xylazine, 5.5 mg every 40 minutes (18 dogs). Endotracheal intubation was carried out in all dogs by direct vision using cuffed Magill tubes. An oesophageal stethoscope was used to monitor the heart and the respiration rates during the intra-operative period. 0.9% normal saline was infused IV in all cases at a rate of 90 ml per hr. (one drop/ 2 sec. : 20 drops/ml). The quality of the anaesthesia was assessed by frequent monitoring of heart and respiration
Material and methods Forty two dogs of either sex admitted to the
Surgical Teaching Unit of the Veterinary Faculty of Zaragoza were used for the study. The dogs weighed between 4 and 50 kg. Details with reference to welght, age, sex and the operation they underwent are shown in Table 1. The following protocol was established: 1. PreoDerative assessment A clinical examination was carried out on each dog. Pulse and respiration rates were recorded. A standard haemogram and a biochemical profile of total plasma protein, BUN, creatinine, AST, ALT and LDH were obtained from each dog. 2. Preanaesthetic medication 2.1. Propionylpromazine (Combelen, Bayer) 185
Proceedings of the 4th International Con-
rates, capillary refill time, absence or presence of pedal and palpebral reflexes, pupiIIary size, eyeball positioning and degree of relaxation of the jaw muscles.
c.
Mean intraop amount of THIOP. Both
groups d Mean intraop amount of XYL. Group 11. e Mean HR. Both groups. f Mean RR. Both groups Student’s t test to compare e and f.
The following calculations were made: a Mean total anaesthetic time b Mean total Thiop. Dose (Ind. + Maint.) Both groups. Results Table 1.
of Veterinary Anaesthesia
Details with reference to weight, age, sex and the operation they underwent.
Group 1 (n= 24)
Group 2 (n = 18)
Weight (kg)
14.6 t 1.8
19.5 2 2.3
Age (months)
41
Sex: m
f
* 12
65 2 10
I l4
I l1 I
10
7
superficial
1
1
abdominal
9
6
orth
14
11
I (I
Operation:
Dosage of propionylpromazine and atropine used as a premedication and the effect produced. (The values shown in the Table are the mean).
Table 2.
Dose
GROUP l(n= 24) 0.8 f 0.11
GROUP 2 (n= 18) 1.1 t 0.14
0.7 2 0.06
0.7 2 0.06
++
++
propionyl promazine (mg) Dose atropine (mg) Effect* +:standing
+ +: Sternal
+ + +: Lateral 186
Proceedinas of the 4th International Conercss of Veterinarv Anaesthesia
Table 3.
Preoperative figures of some physiological constants (The values showed in the Table are the mean)
Group 1(n= 24) 124
120 ? 10
8
5
12
2
1
B.U.N. (mg/100 ml)
29
5
1,71
Creatinine (mg/100 ml)
0.7
L.D.H. (U/L)
681
Table 4.
Group 2 (n= 18)
42 2
0.9 f 0.12
? 0.06 5
440
I 445
165
?
103
Dose of Thiopentone and xyladne (The values showed in the Table are the mean).
GROUP 2 (n= 18)
GROUP 1 (n= 24) Duration of an. (min)
129
Total THIO.dose (mg/kg)
3623
2322
Intraop. amount of THIO (mg)
343
291 f 32.4
Intraop. amount of X Y L (mg)
23
Table 5.
l
?
f
2
7
135 f 9
43.5
6
Intraop. heart and respiration rate figures
GROUP 1 (n=24)
GROUP 2 (n= 18)
Mean HR
127
100 2 18
Mean RR
22f9
?
25
2nf7
187
Pmcedinp of the 4th International Congress of Veterinary Anaesthesia
Hatch R.C. and Wilson R.C. (1988) How valuable is this mix of diazepam, xylazine, and atropine for immobilizing dogs? Vet. Med.
The heart rate decreased significantly in group 2 but no signiticant changes were seen in the respiration rate (P= 0.1) No differences in recovery time from anaesthesia were appreciated between two groups. In the first group of dogs when abdominal surgery was carried out, the surgeon complained that muscle relaxation was poor, but in the second group when xylazine was used, muscle relaxation was better.
260-265.
H s y W.H. (1985) Effects of atropine on xylahe-pentobarbital anaesthesia in dogs: preliminary study. Am. J. Vet. Res. 46,4. Klide A.M., Calderwood H.W., Soma L.S. (1975) Cardiopulmonary effects of xylazine in
Conclusions The results obtained under the conditions described indicate that the use of incremental doses of xylazine in dogs as part of a total intravenous anaesthetic technique in combination with thiopentone improves the level of "analgesia" and muscle relaxation and diminishes the amount of barbiturate required. However, animals with preexisting cardiac disturbances should be considered unsuitable for the use of xylazine in the manner described because of its depressant action on the heart (Knight, 1980).
dogs. Am.J. Vet. Res. 36,7. Knight A.P. (1980)Xylazine. JA.V.MA. 176,5. Kroneberg G., Oberdorf, A. Hoffmeister F., Wirth W. (1%7) Zur pharmakologie von 2-(2,6-1,3-thiazin(Bayer 1470)) eines Hemmstoffes adrenergischer und cholinergischer Neurone. Arch. Pharmakol. Ekp. Path. 256,
257-286. Livingston, A., Nolan, A., Waterman A. (1986/ 1987) The pharmacology of alpha2-adrenergic agonist drugs. Journal of the Association of Veterinary Anaesthetists 14,3-10.
References Benson GJ., Thurmon J.C., Tranquilli WJ., Smith C.W. (1985) Cardiopulmonary effects of an intravenous infusion of gucufenesin, ketamine, and xylazine in dogs. Am. J. Vet. Res. 46,no. 9,18%1898.
Moye RJ., Pailet A., Smith Jr. M.W. (1973) Clinical use of Xylazine in dogs and cats. V.M./ SA.C. 68,236-241.
Clark D.M., Martin A.R., Short CA. (1982) Cardiopulmonary responses to xylazine/ketamine anaesthesia in the dog. JAA.HA. 18, 815-821.
Muir W.W. and Piper F.S. (1977) Effect of xylazine on indices of myocardial contractility in the dog. Am. J. Vet. Res. 38 931-934.
Hall L.W. and Clarke K.W. (1983) Veterinary Anaesthesia., 8th ed Bailliere, Thdall, London.
Newkirk H.L. and Miles D.G. (1974) Xylazine as a sedative analgesic for dogs and cats. Modem Vet. Pract. 55, 677-680.
Haskins S.C., Patz J.D., Farver T.B. (1986) Xylazine and Xylazine -ketamine in dogs. Am. J. Vet. Res. 47,3.
Raptopodus D., Koutinas A., Moustardas N., Papastedadis A. (1985) The effect of xylazine or xylazine plus atropine on blood gases in
188
~
Proceedings of the 4th International Conpas of Veterinary Anaesthesia
sheep. Proc. 2nd. Intl. Cong. Vet. Anesth.
Samy M.T.and Othman G.M. (1985) Empleo clinic0 de ketamina y xilacha en la anestesia del gato. Notiuas Medico-Veterinarias 1/85 72-79. Waterman A., Nolan A. and Livingston A. (1986-1987) The effect of alpha2-adrenergic agonist drugs and their antagonists on respiratory blood gases in conscious sheep. J. Ass. Vet. Anaesth. 14, 11-13.
189
CLINICAL OBSERVATIONS ON THE INTRA-OPERATIVE USE OF XYLAZINE IN THIOPENTONE ANAE!3THESLA IN THE DOG J.I. Cruz. Surgical T e a c h Unit, Veterinary Faculty, Zaragoza, Spain Introduction Xylazine is used as a preanaesthetic drug in the dog, either on its own or in combination with ketamine hydrochloride (Hall and Clarke, 1983). Its use has also been described in combination with diazepam, phenothiazine derivatives or guaifenesin (Benson et al., 1985; Hatch and Wilson, 1988; Clark et al., 1982). The use of xylazine as a pre-medicant in combination with barbiturates has also been reported (Moye, 1973; Hsu, 1985) but the intra-operative use of xylazine is not so well recognised. This study was carried out to assess the use of incremental doses of xylazine given intravenously during a variety of surgical procedures in dogs where inhalation techniques and opioid analgesics were not available and the only anaesthetic agent used was thiopentone sodium.
0.05U.1 mg/kg was given intramuscular-
ly2.2. Atropine sulphate. 0.04-0.2 mg/kg was
injected with the propionylpromazine or immediately afterwards but not if tachycardia was diagnosed previously or if h e dog was under 4 kg body weight and so consequently had a high heart rate. 3. Induction This took place 30 minutes after premedication. "hiopentone sodium (Penthotal, Abbott Laboratories.) 10 mg/kg as a 25%, 1.66% or 1.25% solution was injected by slow intravenous injection. 4. Maintenance For this, the animals were divided into two groups: Group 1: Maintenance by incremental doses of thiopentone, 13 mg every 12.5 minutes (24 dogs). Group 2. Maintenance by incremental doses of thiopentone, 40 mg every 20 minutes or xylazine, 5.5 mg every 40 minutes (18 dogs). Endotracheal intubation was carried out in all dogs by direct vision using cuffed Magill tubes. An oesophageal stethoscope was used to monitor the heart and the respiration rates during the intra-operative period. 0.9% normal saline was infused IV in all cases at a rate of 90 ml per hr. (one drop/ 2 sec. : 20 drops/ml). The quality of the anaesthesia was assessed by frequent monitoring of heart and respiration
Material and methods Forty two dogs of either sex admitted to the
Surgical Teaching Unit of the Veterinary Faculty of Zaragoza were used for the study. The dogs weighed between 4 and 50 kg. Details with reference to welght, age, sex and the operation they underwent are shown in Table 1. The following protocol was established: 1. PreoDerative assessment A clinical examination was carried out on each dog. Pulse and respiration rates were recorded. A standard haemogram and a biochemical profile of total plasma protein, BUN, creatinine, AST, ALT and LDH were obtained from each dog. 2. Preanaesthetic medication 2.1. Propionylpromazine (Combelen, Bayer) 185
Proceedings of the 4th International Con-
rates, capillary refill time, absence or presence of pedal and palpebral reflexes, pupiIIary size, eyeball positioning and degree of relaxation of the jaw muscles.
c.
Mean intraop amount of THIOP. Both
groups d Mean intraop amount of XYL. Group 11. e Mean HR. Both groups. f Mean RR. Both groups Student’s t test to compare e and f.
The following calculations were made: a Mean total anaesthetic time b Mean total Thiop. Dose (Ind. + Maint.) Both groups. Results Table 1.
of Veterinary Anaesthesia
Details with reference to weight, age, sex and the operation they underwent.
Group 1 (n= 24)
Group 2 (n = 18)
Weight (kg)
14.6 t 1.8
19.5 2 2.3
Age (months)
41
Sex: m
f
* 12
65 2 10
I l4
I l1 I
10
7
superficial
1
1
abdominal
9
6
orth
14
11
I (I
Operation:
Dosage of propionylpromazine and atropine used as a premedication and the effect produced. (The values shown in the Table are the mean).
Table 2.
Dose
GROUP l(n= 24) 0.8 f 0.11
GROUP 2 (n= 18) 1.1 t 0.14
0.7 2 0.06
0.7 2 0.06
++
++
propionyl promazine (mg) Dose atropine (mg) Effect* +:standing
+ +: Sternal
+ + +: Lateral 186
Proceedinas of the 4th International Conercss of Veterinarv Anaesthesia
Table 3.
Preoperative figures of some physiological constants (The values showed in the Table are the mean)
Group 1(n= 24) 124
120 ? 10
8
5
12
2
1
B.U.N. (mg/100 ml)
29
5
1,71
Creatinine (mg/100 ml)
0.7
L.D.H. (U/L)
681
Table 4.
Group 2 (n= 18)
42 2
0.9 f 0.12
? 0.06 5
440
I 445
165
?
103
Dose of Thiopentone and xyladne (The values showed in the Table are the mean).
GROUP 2 (n= 18)
GROUP 1 (n= 24) Duration of an. (min)
129
Total THIO.dose (mg/kg)
3623
2322
Intraop. amount of THIO (mg)
343
291 f 32.4
Intraop. amount of X Y L (mg)
23
Table 5.
l
?
f
2
7
135 f 9
43.5
6
Intraop. heart and respiration rate figures
GROUP 1 (n=24)
GROUP 2 (n= 18)
Mean HR
127
100 2 18
Mean RR
22f9
?
25
2nf7
187
Pmcedinp of the 4th International Congress of Veterinary Anaesthesia
Hatch R.C. and Wilson R.C. (1988) How valuable is this mix of diazepam, xylazine, and atropine for immobilizing dogs? Vet. Med.
The heart rate decreased significantly in group 2 but no signiticant changes were seen in the respiration rate (P= 0.1) No differences in recovery time from anaesthesia were appreciated between two groups. In the first group of dogs when abdominal surgery was carried out, the surgeon complained that muscle relaxation was poor, but in the second group when xylazine was used, muscle relaxation was better.
260-265.
H s y W.H. (1985) Effects of atropine on xylahe-pentobarbital anaesthesia in dogs: preliminary study. Am. J. Vet. Res. 46,4. Klide A.M., Calderwood H.W., Soma L.S. (1975) Cardiopulmonary effects of xylazine in
Conclusions The results obtained under the conditions described indicate that the use of incremental doses of xylazine in dogs as part of a total intravenous anaesthetic technique in combination with thiopentone improves the level of "analgesia" and muscle relaxation and diminishes the amount of barbiturate required. However, animals with preexisting cardiac disturbances should be considered unsuitable for the use of xylazine in the manner described because of its depressant action on the heart (Knight, 1980).
dogs. Am.J. Vet. Res. 36,7. Knight A.P. (1980)Xylazine. JA.V.MA. 176,5. Kroneberg G., Oberdorf, A. Hoffmeister F., Wirth W. (1%7) Zur pharmakologie von 2-(2,6-1,3-thiazin(Bayer 1470)) eines Hemmstoffes adrenergischer und cholinergischer Neurone. Arch. Pharmakol. Ekp. Path. 256,
257-286. Livingston, A., Nolan, A., Waterman A. (1986/ 1987) The pharmacology of alpha2-adrenergic agonist drugs. Journal of the Association of Veterinary Anaesthetists 14,3-10.
References Benson GJ., Thurmon J.C., Tranquilli WJ., Smith C.W. (1985) Cardiopulmonary effects of an intravenous infusion of gucufenesin, ketamine, and xylazine in dogs. Am. J. Vet. Res. 46,no. 9,18%1898.
Moye RJ., Pailet A., Smith Jr. M.W. (1973) Clinical use of Xylazine in dogs and cats. V.M./ SA.C. 68,236-241.
Clark D.M., Martin A.R., Short CA. (1982) Cardiopulmonary responses to xylazine/ketamine anaesthesia in the dog. JAA.HA. 18, 815-821.
Muir W.W. and Piper F.S. (1977) Effect of xylazine on indices of myocardial contractility in the dog. Am. J. Vet. Res. 38 931-934.
Hall L.W. and Clarke K.W. (1983) Veterinary Anaesthesia., 8th ed Bailliere, Thdall, London.
Newkirk H.L. and Miles D.G. (1974) Xylazine as a sedative analgesic for dogs and cats. Modem Vet. Pract. 55, 677-680.
Haskins S.C., Patz J.D., Farver T.B. (1986) Xylazine and Xylazine -ketamine in dogs. Am. J. Vet. Res. 47,3.
Raptopodus D., Koutinas A., Moustardas N., Papastedadis A. (1985) The effect of xylazine or xylazine plus atropine on blood gases in
188
~
Proceedings of the 4th International Conpas of Veterinary Anaesthesia
sheep. Proc. 2nd. Intl. Cong. Vet. Anesth.
Samy M.T.and Othman G.M. (1985) Empleo clinic0 de ketamina y xilacha en la anestesia del gato. Notiuas Medico-Veterinarias 1/85 72-79. Waterman A., Nolan A. and Livingston A. (1986-1987) The effect of alpha2-adrenergic agonist drugs and their antagonists on respiratory blood gases in conscious sheep. J. Ass. Vet. Anaesth. 14, 11-13.
189