Diabetes mellitus is a common endocrine disease that is characterized by long-term complications involving the blood vessels, kidneys, nerves, and eyes.1 Subsequently, for diabetic patients undergoing major surgery more frequently than those without diabetes,2 the major risk factors are heart disease, stroke, kidney disease, blindness, and nontraumatic amputation.1 Of importance to the anesthesiologist is preoperative treatment of patients with such complications. Some of the chronic complications of diabetes may be prevented or improved by chronic “tight” control of Type I diabetes, to a certain degree.3 However, the benefits associated with tight control of blood glucose are debatable when considering the benefit-to-risk ratio. For example, tight control of blood glucose benefits diabetics that are undergoing cardiopulmonary bypass, and those undergoing global central nerve system ischemia, but as there is little evidence of benefit to other groups, the benefit-to-risk ratio of tight glucose control has not been assessed.3
The diabetic population is not homogeneous and several diabetic
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syndromes exist. Hyperglycemia is a major phenotype of diabetes mellitus.
The criteria for the diagnosis of diabetes mellitus is one of the following:4 1. Symptoms of diabetes plus random blood glucose concentration 11.1
mmol/L (200 mg/dL) since the last meal.
2. Fasting at least 8 hours plasma glucose 7.0 mmol/L (126 mg/dL).
3. Two-hour plasma glucose 11.1 mmol/L (200 mg/dL) during an oral
glucose tolerance test.
Depending on the etiology of the diabetes mellitus, factors contributing to hyperglycemia may include reduced insulin secretion, decreased glucose utilization, increased insulin resistance (IR), and increased glucose production.4 Etiologic classification of diabetes mellitus:4
I. Type I diabetes (insulin dependent diabetes mellitus, IDDM):
Causes of -cell destruction that leading to absolute insulin
deficiency.
1. Immune-mediated 2. Idiopathic
II. Type II (non-insulin dependent diabetes mellitus, NIDDM):
Range from IR with relative insulin deficiency to an insulin secretory defect with IR.
III. Other specific types of diabetes
1. Genetic defects of -cell function of pancrease characterized
by mutations in:
i. Hepatocyte nuclear transcription factor (HNF) 4
(MODY 1)
ii. Glucokinase (MODY 2) iii. HNF-1 (MODY 3)
iv. Insulin promoter factor (IPF) 1 (MODY 4) v. HNF-1 (MODY 5)
vi. NeuroD1 (MODY 6) vii. Mitochondrial DNA
viii. Proinsulin or insulin conversion 2. Genetic defects in insulin action:
i. Type A IR ii. Leperchaunism
iii. Rabson-Mendenhall syndrome iv. Lipodystrophy syndromes 3. Disease of the exocrine pancreas 4. Endocrinopathies
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5. Drug or chemical-induced 6. Infections
7. Uncommon forms of immune-mediated diabetes
8. Other genetic syndromes sometimes associated with diabetes IV. Gestational diabetes mellitus.
The multifactorial causes of diabetic complications include glycosylation of proteins and glucose reduction to sorbital (which functions as a tissue toxin).5 In addition, glycosylation of the atlanto-occipital joint may limit joint mobility and cause difficulty with airway management (“stiff-neck” syndrome).6 Otherwise hyperglycemia is the major factor in the development of diabetic complications.7 The Somogyi effect also describes the rebound hyperglycemia following a hypoglycemic reaction.8 Careful monitoring ensures successful management of blood glucose perioperatively.
Patients with NIDDM may develop metabolic disorder, coronary artery disease, nephropathy, neuropathy, nontraumatic lower extremity amputations, and adult blindness. With an increasing incidence worldwide, diabetes mellitus will be a leading cause of morbidity and mortality for the foreseeable future.9 In Taiwan, diabetes has become the fourth among the top ten causes of death.10-12
Hyperglycemic response to stress during general anesthesia
It is commonly known that an increased secretion of endogenous catecholamines is found in a neurohormonal response to stress during general anesthesia with subsequent increase of plasma cortisol, glucagon, and glucose, along with hemodynamic changes of increased heart rate, blood pressure, and cardiac output.13 An increased plasma glucose level is associated with poor clinical outcome or cell death during critical illness.14 Surgical mortality rates are on average five times higher for the diabetic population than for the non-diabetic population.3
Hyperglycemia is a common result of stress signals caused by pain and surgical procedure.14 As we know in many reports, volatile anesthetics directly manipulate glucose homeostasis by affecting pancreatic insulin release15-17 and induce hyperglycemia without surgical stress.15, 18-22 The hyperglycemic response is also observed during isoflurane anesthesia that is a consequence of both impaired glucose clearance and increased production of glucose.18 Both sevoflurane and isoflurane anesthesia also impair glucose tolerance to the same degree and is independent of agent and dosage up to 1.5 minimum alveolar concentration (MAC).22
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Methods to increase insulin sensitivity
There is a hope for controlling blood glucose in insulin dependent diabetic patient since the discovery of insulin. However, the IR, especially patients with NIDDM has been become another medical issue to be solved.
Thus, methods to increase insulin sensitivity have become importance.
In Chinese medicine, “Chi” (Qi) is a metaphysical concept of supposed body energy that runs through 365 designated acupuncture points within the hypothesized meridians which can be stimulated by the needles or
“moxibustion” (lighted punks of artemis vulgaris) to balance “Yin and Yang”
by relieving blockage in the flow of “Chi”.23 The regulation of Chi is also similar to the change in the kinetic effects of insulin.24
Opioid analgesics have become the treatment of choice for the management of pain control. Furthermore, opioid participates in the regulation of endocrine processes, including glucose metabolism.25 Activation of -opioid receptors on the insulin-targeted organs seems to be an important role for lowering plasma glucose and increasing insulin sensitivity, although the direct role of -opioid receptors for the improving insulin resistance has not been completely investigated.7 Transcutaneous electrical nerve stimulation (TENS) is a complementary therapy to the
pharmacological management of pain.26 Many clinical studies have reported that TENS also is an adjunct method for the management of postoperative pain.27, 28 It has been shown that postoperative treatment with TENS results in decreased analgesic consumption and lower incidence of postoperative complications.27 Importantly, a study showed that stimulation of the Zusanli (ST36) acupoint was effective in decreasing both the postoperative opioid analgesic needed and opioid-related side effects.29 The implication of this finding is that the location of the stimulating electrodes is significant in determining the efficacy of TENS in reducing postoperative pain. Besides treatment for postoperative pain, TENS has been applied to acupoints to increase muscle strength after acute stroke.30 Of the non-pharmacological methods to manage pain, TENS is the most non-invasive method.
Conversely, needle acupuncture is an invasive, skill-based procedure and the possible risks of broken needles, infection and transient hypotension have been reported.31 A significant animal study using acupuncture found that rats had enhanced hypoglycemic activity and insulin sensitivity when electroacupuncture was applied on bilateral Zusanli acupoints.24 There have been few studies that evaluated the effects of TENS on the specific acupoints, and as such, this clinical investigation is a pioneer study in its field also.32, 33
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