1.
Caudal Epidural Analgesia With Bupivacaine, Medetomidine Alone And In Combination In Dogs
by Usman Rashid (2013-VA-843) | Dr. Hamid Akbar | Prof. Dr. M.Arif Khan | Dr. Imtiaz Rabbani.
Material type: ; Literary form:
not fiction
Publisher: 2105Dissertation note: Epidural analgesia is very old technique used for many regional surgeries in humans as well as in animals. It is very wonderful technique used for regional surgeries and is helpful for intraoperative management of high risk patients, perioperative analgesia, cesarean section, and forelimb amputation and have certain advantages over general anesthesia, include safety and low cost, reduces the use amount for anesthetics drug, and long-acting drugs, are helpful in residual analgesia for up to 24 hours.
Bupivacaine Hydrochloride is amino-amine long acting local anesthetic. As compared to the lidocaine, it is four times more potent, and can show anesthetic effects up to 3-8 hours. It has high potency, prolong duration, and less degree of motor blockade effects with minimal neuro and cardio toxicity effects.
Medetomidine hydrochloride is the most potent alpha-2 adrenoceptor selective agonist. It is a racemic mixture of two optical enantiomers which are, dexmedetomidine and levomedetomidine. When alpha-2 agonists administered epidurally they produce analgesia by stimulating alpha-2 adrenergic receptors present in dorsal horn of the spinal cord, and show antinociceptive properties due to their interaction with noradrenergic receptors of the spinal cord.
The current project is designed to compare the analgesic and hematological efficacy of the Bupivacaine, Medetomidine alone and in combination as epidural analgesia in dogs. For this purpose 18 clinically healthy mongrel dogs weighing 12-15kg were selected. They were divided into three groups with each group contained six dogs (n=6). The groups were named as A, B and C respectively.
Summary
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In group A Bupivacaine HCl, at dose rate of 0.5mg/kg body weight Injected Epidurally, in group B Medetomidine HCl, at dose rate of 0.015mg/kg body weight while in group C combination of Bupivacaine Hydrochloride + Medetomidine Hydrochloride Injected Epidurally.
Time to the onset, duration, ataxia, and the anatomic extent of the analgesia were recorded. Time from injection to loss of sensation was considered as onset of the analgesia. The presence of the analgesia was taken as lack of responses to “pin pricking” and by applying hemostat pressure. Positive responses to needle prick or hemostat pressure shows the presence and anatomic extent of analgesia. The tests were repeated after every 20 minutes until animals regain sensation. Ataxia was graded as 0=none, 1= mild, 2= moderate or 3= severe.
Blood sample were collected directly from the Cephalic vein before and after administration of anesthetic drug. A total of 3 mL blood was collected each time in test tubes containing blood coagulating gel. First sample were taken before anesthetic drug administration and second sample were collected after 60 minutes for evaluation of Liver Function Test.
Results of the present study proved that, minimum time to analgesic onset were shown by group C dogs, followed by group A and group B dogs. Maximum analgesic time duration was shown by group C dogs, followed by group B and group A dogs. After 20 minutes of drug administration ataxic response were same in group A and group C dogs, as 5 out of 6 dogs had sever ataxia. At 20 and 40 minutes after administration of drug, dogs of group A and group C showed maximum spread of analgesia as compare to group B dogs, at 60 minutes post drug administration, dogs of group, A, B and C showed maximum spread of analgesia.
Liver function test were evaluated by three enzymes, Alanine Aminotransferase (ALT), Aspartate Amino Transferase (AST) and Alkaline Phosphatase (ALP). Blood samples were collected before and after 60 minutes of drug administration. First these tests were evaluated within
Summary
45
each group. ALP, AST and ALP values were non-significant in alone administration of Bupivacaine HCl and Medetomidine HCl, while significant rise in ALP value were observed in group C dogs, treated with Bupivacaine HCl in combination with Medetomidine HCl. When ALT, AST, and ALP were compared among all three treatments, their results were non-significant as with minor change in P-value in post 60 minutes of anesthetic drug administration, which showed that all three treatments are independent and did not effect these parameters.
Elective and emergency surgeries of hind limbs are very common in dogs, which demand appropriate, best, and safest regional anesthesia, with minimum and prolong duration of analgesic time. Maximum, uniform, and rapid spread of analgesia and having least effects on serological parameters of the animal. Present study suggested that epidural administration of Bupivacaine HCl in combination with Medetomidine HCl proved to be the safest anesthesia by showing rapid onset, prolong duration of analgesia time, early recumbency of animal, with maximum anatomic extent of analgesia in short duration time. Combination of Bupivacaine HCl and Medetomidine HCl showed least effects on serological parameters of dogs. Availability: Items available for loan: UVAS Library [Call number: 2434-T] (1).
2.
Effects Of Partial And Complete Splenectomy On Blood Parameters Of Rabbit
by Waleed Iqbal (2009-va-151) | Dr. Asim Khalid Mahmood | Dr. Hammad bin Rasheed.
Material type: ; Format:
print
; Literary form:
not fiction
Publisher: 2016Dissertation note: A comparative study of 2 procedures i.e. partial and complete splenectomy was performed to assess their clinical application. For this, 16 experimental rabbits were divided into 2 groups i.e. A and B with 8 rabbits in each group. In Group A, complete splenectomy whereas in group B, partial splenectomy was performed.
The parameters evaluated for the success of splenectomy procedure were erythrocyte, leucocyte and platelet count and readings were observed on day 0 (before surgery) and day 10, 20 and 30 (after the procedure).
Erythrocyte count
The values of all the 8 rabbits in group A, when recorded on day 0, were falling in the physiological range of erythrocyte count (5-8 x 106/uL), as all the rabbits were healthy and non-operated. This is in accordance with the physiological findings as depicted by Merck in 2015.
Later on, when the second reading was obtained at day 10 (after surgery), a decrease in the level of erythrocytes was noted (within normal range) in 6 rabbits of this group. This is in compliance with the findings of Mole (1925) who observed an immediate drop in erythrocytes after complete splenectomy. Similarly Dellenback et al. (1969) has also reported a decrease in haemoglobin concentration after splenectomy procedure though his study was on beagle dogs. On the other hand, Lorber et al. (1958) has also reported obvious change in erythrocyte count after such procedure. This decrease in erythrocyte count immediately after splenectomy might be partly due to haemorrhage at the operation site and partly due to the removal of spleen which may replenish the loss of erythrocytes. Furthermore this removal of spleen must temporarily upset the balance of the haemopoietic system.
However anemia was recorded in only 2 rabbits i.e. rabbit no. A2 and A4 where the erythrocytes value had dropped below the normal range. Chaudhary et al (1997) has also reported anemia in dogs after complete splenectomy and related it to the loss of spleen-iron regulatory function. The iron storage was impaired temporarilyand furthermore there is loss of iron from kidneys. This might result in decreased erythrocyte count as well as synthesis of erythrocyte was also impaired due to depletion of iron from body (Waldmann et al., 1960).
. The third reading was taken on day 20 post-operatively and it was noted that the value of erythrocyte concenteration dropped further in rabbit no. A1, A3, A5, A6, A7 and A8 though the values were still in normal range, indicating that the body homeostasis had not managed to bring the erythrocyte count back to its day 0 normal level. Similar findings were reported by Mole on 21 days and Bolbol et al. in 1981 had reported the same findings but his study was in sheep.
On the other hand, the two rabbits which showed anemia on day 10 started recovering at day 20 and their erythrocyte level showed improvement though it was lower than its original value but was falling in normal range indicating the restoration of erythropoiesis in body. When the last reading was taken on day 30, the erythrocyte levels of all rabbits were almost near to 0 day normal values. Our finding is in compliance with Mole (1925) who stated that this increase in erythrocytes after day 10 to day 30 was due to a persistence of the old erythrocytes which would otherwise have been destroyed in the presence of the spleen. The drop in erythrocyte count at day 10 and 20 was significant (P < 0.05). But the ultimate value on day 30 returned to the normal range and differ non-significant with 0 day value.
In group B, unlike group A, the drop in erythrocyte level was also recorded but drop was non-significant which ultimately returned near to 0 day value on day 30.
When group A was compared with group B, a non-significant drop in erythrocytes was recorded (P > 0.05) on day 10, 20 and 30, though there were fluctuations. Mole (1925) found similar results in his partial splenectomized rabbits.
Leucocyte count
When the leucocyte count was evaluated in group A, contrary to the findings of erythrocytes in this group, a significant increase in no. of leucocytes was recorded, with the highest value recorded at day 10 in all rabbits except A6 where there was a consistent drop recorded on day 10th, 20th and 30th. This unusual depression in leucocytes in A6 might be due to stress but these values were still within normal range. Similar findings were reported by Lifshitz in 1937 and Bessler in 2004 in rats. Increase in these leucocytes after complete splenectomy is due to the susceptibility of body for intermittent and transient type of nonspecific septicemia as stated by Weinstein et al. in 1983. Lifeshitz (1937) also concluded that one of the functions of spleen is to exert an inhibitory effect on leucopoietic centers
When leucocyte values were recorded in group B rabbits, a similar significant increase was recorded in all the rabbits of this group and the values in B1, B2, B3, B4 and B7 were more than the physiological ranges whereas the increase was within physiological rabge in B5, B6 and B8. Thereafter the leucocytes number started dropping on day 20 and ultimately came to physiological range on day 30. But the level was still higher than 0 day values and a significant difference was recorded.
When leucocyte count of group A was compared with partial splenectomised rabbits of group B, a significant increase (p < 0.05) was noted in group B on day 10, which kept falling uniformly in all rabbits except B5, where the values dropped abruptly from 11.10 to 7.89 on day 30. Palmer also observed marked leucocytosis after partial splenectomy but his study was on rats and he stated that this marked leucocytosis after partial splenectomy is due to inflammation at surgery site which didn’t produced in complete splenectomy. A significant increase of leucocyte number was recorded on day 30 in group B as compared to group A.
Platelet count:
The third parameter recorded was platelet count which revealed a significant thrombocytosis (P < 0.05) on day 10, 20, and 30 of each rabbit of group A and final values on day 30 were more than the normal range. In 2006, Bidus et al. also observed thrombocytosis after complete splenectomy however his study was performed on humans. Thrombocytosis may be related to the removal of whole splenic tissue which is the storage organ for platelets (Mole. 1925). Balz and Minton (1975)also performed splenectomy in patients and found an acute increase in platelet count.
Contrary to this, in group B, platelet number significantly increased on day 10 but thereafter kept on dropping on day 20 and 30 and the final values were in normal ranges except in rabbit B6 in which platelet count kept on increasing on day 20 and then dropped to near 0 day value on day 30. Similar pattern was seen in partial splenectomised rabbits in the study of Mole (1925). Decrease in platelet count from 10th day to 30th day post-splenectomy indicated that left over splenic tissue has started its normal physiological function of restoring platelets. However, overall platelet count fluctuations in partial splenectomized rabbits were non-significant (P>0.05).
Using repeated measurement ANOVA test, when the overall comparison of group A and B was made in terms of erythrocyte, leucocyte and platelet count, considering the values on day 0 and day 30, a non-significant difference was observed in erythrocyte count (P=0.154) and platelet count (P=0.984) between both the groups. However significant difference found in leucocyte level (P=0.013), between both groups (figure 4.5, 4.6 and 4.7). Mean value of leucocyte count in group A was 9.410 (S.D=0.504) as compared to group B in which mean was 11.445 (S.D=0.504) indicating that complete splenectomy is better than partial splenectomy.
Compiling the overall results, keeping in view the values of all parameters in both groups, we concluded that partial splenectomy procedure has no superiority over the complete one. Both the procedures have almost similar results except some temporary fluctuations in studied parameters. Wherever, the splenectomy is required, one can go for either procedure. However, complete splenectomy is better choice of procedure due to difficulties seen during removing partial spleen.
Availability: Items available for loan: UVAS Library [Call number: 2548-T] (1).
