Abimussi, Caio J.X.; Floriano, Beatriz P.; Wagatsuma, Juliana T.; Canceli, Carlos H.B.; Ferreira, Joana Z.; Garcia-Pereira, Fernando L.; Santos, Paulo S.P. dos; Oliva, Valéria N.L.S.

doi:10.1590/S0100-736X2017000200007

ABSTRACT:

The aim of the study was to assess hemodynamic changes and complications of spinal anesthesia with ropivacaine at different baricities. Six beagle dogs aged four years. The dogs were anesthetized with isoflurane and subjected to the following treatments: G_hypo = spinal anesthesia with hypobaric ropivacaine (0.5mL of 0.9% NaCl+0.5mL ropivacaine at 0.75%); G_iso = isobaric spinal anesthesia (0.5mL of 0,906% NaCl+0.5mL ropivacaine at 0.75%); G_hyper = hyperbaric spinal anesthesia (0.5mL of 10% glucose+0.5mL ropivacaine at 0.75%). After induction to anesthesia and maintenance with isoflurane, animals were positioned in right lateral recumbency for pulmonary artery catheterization through the left jugular vein. Spinal anesthesia was carried out with injection of 1mL of local anesthetic using a 22G Quincke tip needle in the L5-L6 space along 1 minute. Dogs were maintained under inhalation anesthesia for 60 minutes in ventral recumbency. HR, F_R, MAP, CO, mPAP and body temperature progressively increased in all groups, whereas PCWP increased only in G_HYPO at all time points. The TPRI showed significantly higher values in G_ISO at M₁, M₅ and M₁₀ compared to the other groups, except for M₅, during which G_ISO differed only from G_HYPER. The PVRI increased at M₅ compared to M_B in G_ISO. Side effects such as unilateral motor deficit, bladder atony, excitation, acute pain and chemosis were observed. The hemodynamic changes were not relevant, although inhalation anesthesia with isoflurane might have influenced the results. The changes observed in the study demonstrate that motor blockade is likely to be obtained with isobaric and hyperbaric ropivacaine, thereby confirming the influence of baricity on the type of nerve fibers on the spinal cord. The isobaric solution results in a mixed blockade (motor and sensory blockade). Hemodynamic changes such as hypotension and bradycardia were not evidenced in this study, although local anesthetics were administered in low volumes and together with isoflurane anesthesia. Regarding complications, post-anesthetic observation is warranted in order to identify and treat possible changes. Spinal anesthesia in the conditions studied did not cause hemodynamic changes in isoflurane-anesthetized dogs and is thus considered safe for routine practice, although a few complications are prone to occur.

INDEX TERMS:
Regional anaesthesia; spinal cord; subarachnoid; cardiovascular; complications; canine.

[1] *Autor para correspondência
: cjxabimussi@hotmail.com

Variável	Grupo	Momentos
Variável	Grupo	MB	M1	M5	M10	M15	M30	M60
FC	GHIPO	133±22,1^b	139±23,0^ab	135±19,9^ab	137±18,7^ab	139±17,7^ab	139±14,0^ab	148±12,6^a
	GISO	130±14,0^b	133±17,0^b	134±15,8a^b	134±14,0^ab	137±14,4^ab	143±13,8^ab	146±12,8^a
	GHIPER	130±13,7^bc	122±19,9^c	126±20,7^bc	130±12,8^bc	131±14,6^bc	137±16,8^b	152±17,7^a
F	GHIPO	14±4,1^b	16±4,9^ab	17±6,1^ab	17±6,5^ab	21±9,4^a	19±7,8^ab	20±9,9^a
	GISO	15±5,4	18±9,8	16±9,2	16±5,3	15±5,1	17±6,6	18±3,6
	GHIPER	12±4,0	10±2,6	13±2,7	12±2,8	12±2,8	13±3,7	16±6,5
Temp	GHIPO	37,3±0,38^a	37,0±0,21^ab	36,9±0,18^b	36,8±0,21^b	36,8±0,23^b	36,8±0,30^b	36,9±0,60^ab
	GISO	37,4±0,71^a	36,9±0,78^ab	36,7±0,80^b	36,7±0,72^b	36,7±0,73^b	36,7±0,69^b	37,0±0,68^ab
	GHIPER	37,4±0,29^a	36,8±0,45^b	36,7±0,45^b	36,7±0,50^b	36,7±0,51^b	36,7±0,55^b	37,0±0,61^b
PAM	GHIPO	83±20,2^b	86±20,8^b	83±20,0^b	81±19,5^b	86±24,3^b	97±17,7^ab	105±16,4^a
	GISO	75±6,5b	87±15,1^ab	81±10,8^b	80±10,3^b	87±12,8^ab	89±12,3^ab	96±8,1^a
	GHIPER	71±6,1^b	71±8,7^b	73±12,3^b	73±9,8^b	74±8,1^b	83±9,0^b	102±10,0^a
IC	GHIPO	5,1±2,49^b	5,4±2,49^b	5,4±1,92^b	5,7±2,11^b	5,9±1,84^b	6,2±1,52^ab	7,3±2,43^a
	GISO	4,6±1,60^ab	4,5±1,38^b	4,5±1,43^b	4,5±1,30^b	5,7±1,85^ab	5,7±1,84^ab	6,0±1,48^a
	GHIPER	5,0±1,36^bc	4,6±1,69^c	4,9±1,57^bc	5,0±1,4^bc	5,0±1,53^bc	5,8±2,12^b	7,3±1,94^a
PAPm	GHIPO	16±2,7^b	18±4,3^ab	20±0,8^a	19±2,9^ab	20±1,3^a	19±3,2^ab	20±3,1^a
	GISO	15±3,4^b	20±2,3^a	20±1,6^a	20±1,9^a	20±2,4^a	22±2,0^a	21±2,4^a
	GHIPER	16±2,2^c	18±2,5^bc	18±3,2^bc	19±3,2^b	18±2,8^b	19±2,7^b	21±4,1^a
PCPm	GHIPO	9±2,3^b	11±3,1^ab	11±2,6^ab	11±2,5^ab	11±2,0^ab	12±2,9^a	13±2,8^a
	GISO	8±1,2	10±1,8	9±1,7	10±2,5	9±2,1	10±2,3	10±1,6
	GHIPER	8±2,7	10±3,4	10±3,1	10±2,9	10±2,8	10±3,1	10±2,6
IS	GHIPO	37±11,1^b	38±12,6^b	39±8,7^b	40±10,1^b	42±8,6^ab	44±6,9^ab	49±12,5^a
	GISO	35±9,8	33±7,2	33±7,1	33±6,4	41±10,7	40±10,4	41±7,5
	GHIPER	38±9,3^b	37±10,5^b	39±8,6^b	39±9,6^b	38±10,5^b	42±12,3^b	48±10,1^a
ITVE	GHIPO	6,2±4,91^b	6,6±4,60^b	6,3±3,83^b	6,6±4,15^b	7,1±3,73^b	8,3±2,80^ab	10,3±3,76^a
	GISO	4,7±1,64^b	5,5±2,26^ab	5,0±1,84^b	4,9±1,42^b	6,7±2,27^ab	6,8±2,34^ab	7,8±1,63^a
	GHIPER	4,7±1,07^bc	4,4±1,64^c	4,8±1,64^bc	5,0±1,47b^c	5,0±1,59^bc	6,7±2,78^b	10,2±3,23^a
IRPT	GHIPO	1551±583	1507±577^B	1405±507^aB	1312±444^b	1307±477	1377±402	1347±544
	GISO	1570±710	1725±421^A	1646±577^a	1610±541a	1480±656	1456±588	1453±449
	GHIPER	1332±583	1476±630^B	1393±576^b	1371±604^b	1379±548	1349±507	1254±362
IRVP	GHIPO	145±70,1	127±62,6	166±83,4	126±67,2	148±71,8	106±40,9	87±49,7
	GISO	139±61,7^b	204±34^ab	212±53,8^a	184±23,7^ab	180±65,2^ab	184±57,1^ab	159±30,9^ab
	GHIPER	140±45,4	176±101,2	155±70,2	152±52,9	157±63,8	140±72,2	137±55,0

Variável	Grupo	Momento
Variável	Grupo	MB	M15	M30	M60
pH	GHIPO	7,28±0,023	7,30±0,036	7,29±0,034	7,32±0,060
	GISO	7,28±0,035	7,28±0,026	7,30±0,036	7,31±0,034
	GHIPER	7,28±0,034	7,28±0,022	7,30±0,023	7,29±0,031
PaO2 (mmHg)	GHIPO	495±55,6	494±44,6	494±32,6	503±29,5
	GISO	453±98,9	460±72,2	445±73,0	432±80,6
	GHIPER	496±62,2	496±53,3	493±55,9	513±30,6
PvCO2 (mmHg)	GHIPO	50±4,9	49±6,3	39±17,4	48±6,4
	GISO	53±3,1	52±5,5	51±3,8	51±3,9
	GHIPER	52±6,5	51±4,4	51±3,9	49±6,3
BEecf * (mmHg)	GHIPO	-2,5 (-6/1)	-3 (-6/1)	-3 (-6/1)	-2,5 (-5/1)
	GISO	-1 (-6/1)	-2,5 (-6/0)	-1 (-6/3)	-2,5 (-5/1)
	GHIPER	-1 (-7/-1)	-2,5 (-8/0)	-1 (-5/1)	-2 (-5/1)
HCO3 (mmHg)	GHIPO	24±2,1	24±2,2	24±1,7	23±2,0
	GISO	25±2,6	24±2,4	25±3,0	24±2,2
	GHIPER	24±2,7	24±2,8	24±2,2	25±1,7
PaCO2 (mmHg)	GHIPO	51±4,8	49±5,9	50±3,2	48±8,0
	GISO	53±5,7	51±6,1	51±5,6	48±6,0
	GHIPER	52±8,4	50±6,8	51±5,2	51±3,9
PvO2 (mmHg)	GHIPO	99±34,3^ab	104±29,1^ab	92±14,0^b	115±41,2^a
	GISO	96±28,9	108±22,1	109±38,1	105±28,8
	GHIPER	81±16,4^b	80±18,1^b	90±19,1^ab	98±23,8^a
SvO2 (%)	GHIPO	94±2,7	96±2,6	96±2,2	96±2,6
	GISO	95±3,5	95±5,1	95±4,2	96±2,6
	GHIPER	93±3,3^b	92±5,0^b	95±2,9^a	95±3,2^a

Reflexo	Grupo	Lado	Momentos
Reflexo	Grupo	Lado	R0	R30	R60	R120
Patelar	GHIPO	E	2 (0-2)	2 (1-2)	2 (2-2)	2 (2-2)
	GHIPO	D	1 (0-2)	2 (0-2)	2 (0-2)	2 (1-2)
	GISO	E	2 (0-2)	2 (0-2)	2 (0-2)	2 (2-2)
	GISO	D	1 (0-2)	2 (0-2)	2 (0-2)	2 (2-2)
	GHIPER	E	2 (0-2)	2 (1-2)	2 (2-2)	2 (2-2)
	GHIPER	D	2 (0-2)	2 (0-2)	2 (1-2)	2 (1-2)
Tibial	GHIPO	E	2 (0-2)	2 (0-2)	2 (2-2)	2 (2-2)
	GHIPO	D	2 (0-2)	2 (0-2)	2 (2-2)	2 (2-2)
	GISO	E	2 (0-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GISO	D	1 (0-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GHIPER	E	2 (0-2)	2 (1-2)	2 (2-2)	2 (2-2)
	GHIPER	D	2 (0-2)	2 (1-2)	2 (2-2)	2 (2-2)
Interdigital	GHIPO	E	2 (0-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GHIPO	D	2 (1-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GISO	E	2 (1-2)	2 (1-2)	2 (2-2)	2 (2-2)
	GISO	D	2 (1-2)	2 (1-2)	2 (2-2)	2 (2-2)
	GHIPER	E	2 (2-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GHIPER	D	2 (2-2)	2 (2-2)	2 (2-2)	2 (2-2)
Panículo	GHIPO	E	2 (0-2)	2 (0-2)	2 (2-2)	2 (2-2)
	GHIPO	D	2 (0-2)	2 (0-2)	2 (2-2)	2 (2-2)
	GISO	E	2 (0-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GISO	D	2 (0-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GHIPER	E	2 (0-2)	2 (1-2)	2 (2-2)	2 (2-2)
	GHIPER	D	2 (0-2)	2 (0-2)	2 (0-2)	2 (2-2)
Propriocepção Torácica	GHIPO	E	2 (2-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GHIPO	D	2 (2-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GISO	E	2 (2-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GISO	D	2 (2-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GHIPER	E	2 (2-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GHIPER	D	2 (2-2)	2 (2-2)	2 (2-2)	2 (2-2)
Propriocepção Pélvica	GHIPO	E	2 (1-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GHIPO	D	2 (0-2)	2 (1-2)	2 (2-2)	2 (2-2)
	GISO	E	2 (1-2)	2 (1-2)	2 (2-2)	2 (2-2)
	GISO	D	2 (1-2)	2 (2-2)	2 (2-2)	2 (2-2)
	GHIPER	E	2 (1-2)	2 (1-2)	2 (2-2)	2 (2-2)
	GHIPER	D	2 (1-2)	2 (2-2)	2 (2-2)	2 (2-2)

Brasil

Brasil

Efficacy and hemodynamic effects of spinal anesthesia with isobaric, hypobaric or hyperbaric ropivacaine in dogs anesthetized with isoflurane

ABSTRACT: