Diabetic autonomic neuropathy: Abnormal cardiovascular reactions under general anesthesia

Abstract

The influence of diabetic autonomic neuropathy upon the behavior of the circulatory system was investigated in 56 patients who had undergone ophthalmological surgery. A standardized test combination (variability in heart rate during deep breathing. Valsalva ratio, 30:15 ratio, change in blood pressure from lying to standing, sustained handgrip test) was used to study the patients' cardiovascular reflectory reactions. The patients were then divided into the following groups: Group I, non-diabetics. Group II, diabetics without autonomic neuropathy. Group III, diabetics with autonomic neuropathy. The anesthetic (induction by barbiturates and conduction by inhalation agents) and the surgical procedure (pars plana vitrectomy) were standardized and always identical. During anesthesia patients in group III experienced hypotensive reactions (systolic blood pressure below 90 mm Hg) significantly more often (72.2%) than patients in group I (25%). In order to achieve stability in blood pressure the patients of group III had to be given vasoactive drugs much more often (77.8%) than the patients of group I (12.5%) and those of group II (35.7%). We found a significant correlation between the degree of autonomic dysfunction and the largest drop in blood pressure under narcosis (r = -0.60, P less than 0.001). However, marked variability in heart rate and cardiac rhythm disorders during anesthesia were seen only in patients of groups I and II. These results prove the atypical hemodynamic behavior and especially the extreme instability in blood pressure in diabetic autonomic neuropathy under general anesthesia. Therefore we consider it to be very helpful to check the cardiovascular reflectory status of diabetics preoperatively.

The Autonomic Symptom Profile

“…Patients with diabetic autonomic neuropathy and autonomic failure may have increased instability of blood pressure and increased intraoperative mortality. [10][11][12][13] In addition, the function of small myelinated and unmyelinated fibers may improve with treatment. For instance, Fagius et al 14 found improvement in heart rate deep breathing in diabetics treated with aldose reductase inhibitors.…”

Impaired compensatory response to hypovolaemic circulatory stress in type 1 diabetes mellitus

“…[1][2][3][4][5][6] Diabetes patients with cardiovascular autonomic neuropathy (CAN) are at even greater risk of hypotension during surgery. 4,5,7 Lower body negative pressure (LBNP) is an excellent model for acute haemorrhage and hypovolaemic circulatory stress. 8,9 Orthostatic hypotension is more common in diabetes patients, 3,4 but also diabetes patients with no or only mild neuropathy have increased risk of orthostatic hypotension, signalling other contributory factors.…”

Anesthetic considerations in diabetic patients. Part II: intraoperative and postoperative management of patients with diabetes mellitus

“…In contrast, Keyl et al [8] found no relationship between hemodynamic instability during anesthetic induction and abnormal autonomic function tests, although most of the diabetic patients they studied had impaired autonomic function. However, many other reports [2][3][4][5][6][7]9] emphasize the importance of diabetic neuropathy in patients with hemodynamic instability during the perioperative period. Latson et al [7] speculated several probable mechanisms for this hemodynamic instability.…”

“…There are many reports related to hemodynamic instability during induction and maintenance of anesthesia in diabetic patients [2][3][4][5][6][7]. Burgos et al [2] examined the effects of diabetes on hemodynamic instability in patients undergoing elective ophthalmic surgery under general anesthesia.…”