Anaesthetic requirement and stress hormone responses in patients undergoing lumbar spine surgery: anterior vs. posterior approach

Abstract

Background: The intensity of nociceptive stimuli reflects the severity of tissue injury. The anaesthetic requirement and stress hormonal responses were determined to learn whether they differ according to different surgical approaches (anterior vs. posterior) during the spinal surgery. Methods: Patients undergoing lumbar spine surgery without neurological deficits were divided into two groups: one having posterior (n 5 13) and the other having anterior fusion (n 5 13). The end-tidal sevoflurane concentrations (ET SEVO ) required to maintain the bispectral index score at 40-50 were determined. Mean arterial pressure (MAP), heart rate (HR), central venous pressure (CVP), serum osmolality and plasma concentrations of catecholamines, cortisol and vasopressin (AVP) were measured. Results: There were no differences in MAP, HR, CVP and serum osmolality between the groups. ET SEVO was higher in the anterior than in the posterior group (Po0.05). The plasma concentrations of norepinephrine and cortisol increased in both groups during the surgery, whereas those of epinephrine remained unchanged. AVP concentrations increased during the surgery in the anterior group, and remained unaltered in the posterior group. The anterior group needed more analgesics (Po0.01) during the first 1 h after the operation. Conclusions: The anterior approach required a deeper level of anaesthesia while undergoing spinal surgery and more use of post-operative analgesics than the posterior approach. It was also associated with a more pronounced AVP release during the surgery.

Vasopressina plasmática em pacientes submetidos à correção de aneurisma de aorta infrarrenal

“…These findings lead us to conclude, in accordance with other authors' statement, that, in intra-abdominal surgeries (as in the case of conventional AAA repair), noxious stimulus, probably mediated by the autonomic nervous system, are, really, the most important factors for AVP increased releasing [6,7,10].…”

“…While some authors defend that acute hypotension can stimulate AVP release since arterial pressure drops are often seen during and after anesthetic/surgical procedures [8], others disagree as they had not found a significant correlation between plasma AVP concentrations and arterial pressure levels at different times of surgical procedures [9]. So, despite the well documented plasmatic AVP increase during major surgical procedures, the subjacent mechanisms responsible for this exceptional AVP releasing to remain incompletely understood [5,10].…”

“…The pathophysiologic mechanisms responsible for this dramatic increase in plasma AVP in the per-operative period of major scheduled surgical procedures had not yet been fully clarified [5,24], but it can be influenced by the type [4,5,7,8,10] and invasiveness [25] of the surgical procedure, the type of employed anesthesia [24,26], and by hemodynamic [8,27] and/or serum osmolarity alterations in the per-operative period [24].…”

Intraoperative Changes in Blood Pressure, Heart Rate, Plasma Vasopressin, and Urinary Noradrenalin During Elective Ovariohysterectomy in Dogs: Repeatability at Removal of the 1st and 2nd Ovary

“…In 1 study, 2 different approaches for lumbar spine surgery were compared. An intraoperative increase of vasopressin levels was observed in 1 group and this group required more postoperative analgesics …”

Intraoperative hypernatremia and polyuric syndrome induced by dexmedetomidine

“…Therefore, oliguria is common during surgery. Oliguria is also associated with a pronounced release of AVP during spinal surgery [1]. Dexmedetomidine, a highly selective, short-acting intravenous alpha-2 agonist, has been used as a component of anesthetics due to its imidazoline receptor affinity, which provides analgesic, anxiolytic, and antinociceptive effects without respiratory depression [2].…”