Influence of S(+)-ketamine analgesia in renal intraoperative ischemia: histological study in rats

Abstract

Purpose: To study in rats the effect of S(+)-ketamine on the renal histology after intraoperative hemorrhage. Methods: Twenty male Wistar rats, anesthetized with sodium pentobarbital, were randomly divided in 2 groups: Gl -control (n=l0) and G2 -S(+)-ketamine (n=10), both submitted to arterial hemorrhage of 30% of volemia in 3 moments (10% each 10 min) 60 min after anesthesia. G2 received S(+)-ketamine, 15 mg. kg-1, i.m., 5 min after anesthesia and 55 min before the 1 st hemorrhage moment (Ml). Medium arterial pressure (MAP), rectal temperature (T) and heart rate were monitored. The animals were sacrificed in M4, 30 min after the 3 rd hemorrhage moment (M3) and the kidneys and blood collected from hemorrhage were utilized for histological study and hematocrit (Ht) determination. Results: There were significant reduction of MAP, T, and Ht. The histological study verified G1 = G2 for tubular dilation, congestion, and necrosis. The total score addition were significant1y different and G2 > G 1. Conclusion: Hemorrhage and hypotension determined changes in kidney histology. The rise in catecholamine blood concentration probably was the cause of S(+)-ketamine-induced higher score of histological changes. Key words: Anesthesia and Analgesia. Pentobarbital. Kidney. Ischemia. Hemorrhage. Hypotension. Hypovolemia. RESUMOObjetivo: Investigar, em ratos, o efeito da S(+)cetamina na histologia renal após hemorragia intra-operatória. Métodos: Vinte ratos Wistar machos, anestesiados com pentobarbital sódico, foram divididos, aleatoriamente, em 2 grupos: G1 -controle (n=10) e G2 -S(+)cetamina (n=10), submetidos a hemorragia de 30% da volemia em 3 momentos (10% a cada 10 min) 60 min após anestesia. G2 recebeu S(+)cetamina, 15 mg. kg -1 , i.m., 5 min após anestesia e 55 min antes do 1. o momento de hemorragia (M1). Foram monitorizadas a pressão arterial média (PAM), temperatura retal (T) e freqüência cardíaca. Os animais foram sacrificados (M4) 30 min após o 3. o momento de hemorragia (M3). Os rins e o sangue das hemorragias foram utilizados para estudo histológico e do hematócrito (Ht). Resultados: Houve redução significativa da PAM, T e Ht. Na histologia, G1=G2 na dilatação tubular, congestão e necrose. A soma total dos escores foi significativamente diferente e G2>G1. Conclusão: Hemorragia e hipotensão determinaram alterações na histologia renal. O aumento da concentração sangüínea de catecolaminas provavelmente determinou escores mais altos de alterações histológicas com o uso de S(+)cetamina.

Ischemic Postconditioning and Subanesthetic S(+)-Ketamine Infusion: Effects on Renal Function and Histology in Rats

“…While the effects of NMDAR antagonists on the modulation of glomerular tone are still not fully understood, elevated serum levels of catecholamines, a dose-dependent response to ketamine administration, has a negative role in renal function, supporting our choice of a low-dose regimen with the more potent isomer. The highest scores for tubular lesions have been attributed to the use of S(+)-ketamine in rats associated with higher levels of catecholamines [ 22 ]. The use of subanesthetic doses preserves anti-inflammatory activity while reducing sympathomimetic action [ 23 ].…”

A minimally painful, comfortable, and safe technique for hemodialysis catheter placement in children: Superficial cervical plexus block

“…Yet, ketamine has several serious side effects, including hypertension, tachycardia, psychosomatic effects, and a long recovery time . Moreover, in patients with reduced kidney perfusion, ketamine‐induced sympathetic system activation may cause further kidney damage . Because of these side effects, ketamine must be used carefully in dialysis patients.…”

High doses of ketamine to improve neuronal edema in subarachnoid hemorrhage: we should consider other undesirable organ targets

“…We would like to make some comments. S-ketamine is a non-competitive N-methyl-D-aspartate (NMDA) receptor ion channel blocker [2]. Its action is not limited to the brain, and as intensivists, we need to be mindful of the effects of ketamine upon other organs, especially when ketamine is used in high doses.…”

“…Its action is not limited to the brain, and as intensivists, we need to be mindful of the effects of ketamine upon other organs, especially when ketamine is used in high doses. Negative effects of these high doses have been described in the kidney [2,3]. Renal medullary oxygenation is strictly balanced by a series of control mechanisms, which match regional oxygen supply and consumption [2].…”

“…Negative effects of these high doses have been described in the kidney [2,3]. Renal medullary oxygenation is strictly balanced by a series of control mechanisms, which match regional oxygen supply and consumption [2]. Failure of these controls renders the outer medullary region susceptible to acute or repeated episodes of hypoxic injury, which may lead to acute tubular necrosis (ATN), especially of the thick ascending limbs [2].…”