Postischemic hyperglycemia worsens neurologic outcome after spinal cord ischemia

What is the optimal range of glycemic control for non-diabetic patients undergoing gastroenterological surgery? A single-center randomized controlled trial using an artificial pancreas

BACKGROUND

This study aimed to determine the optimal target range of perioperative glycemic control for gastroenterological surgery. A closed-loop-type artificial pancreas (AP) was used to diminish the negative impact of hypoglycemia and glycemic variability during tight glycemic control.

METHODS

In this single-center randomized trial, non-diabetic patients were assigned to tight (80-110 mg/dL) or moderate glycemic control (110-140 mg/dL) groups between August 2017 and May 2021. AP was used from the intraoperative period until discharge from the intensive care unit. The primary endpoint was the serum interleukin (IL)-6 level on the third postoperative day (3POD), and the secondary endpoints included clinical outcomes.

RESULTS

Recruitment was closed before reaching the planned number of patients due to slow enrollment. Tight glycemic control (n = 62) resulted in lower mean glucose levels than moderate glycemic control (n = 66) (121.3 ± 10.8 mg/dL vs. 133.5 ± 12.0 mg/dL, p < 0.001). Insulin was administered at a 65% higher rate for tight glycemic control, achieving appropriate glucose control more than 70% of the treatment time. No hypoglycemia occurred during the AP treatment. No significant difference was observed in serum IL-6 levels on 3POD (23.4 ± 31.1 vs. 32.1 ± 131.0 pg/mL, p = 0.64), morbidity rate, surgical mortality rate, or length of hospital stay between the two groups.

CONCLUSIONS

Clinically relevant short-term results did not differ, implying that 80-110 and 110-140 mg/dL are permissible glycemic control ranges when using AP in non-diabetic patients undergoing gastroenterological surgery. (Registered in UMIN; UMIN000028036).

Diabetes, dysglycemia, and vascular surgery

BACKGROUND

Abnormalities in glucose metabolism are common in patients with arterial disease. Chronic hyperglycemia and insulin resistance contribute to the complexity of vascular disorders. They also overlap with the effects of perioperative hyperglycemia on adverse perioperative outcomes. We provide an overview of the pathophysiologic consequences of dysglycemia and the evidence behind glycemic control in patients undergoing vascular surgery.

METHODS

We searched the literature for major studies evaluating the pathophysiology of hyperglycemia in microvascular and macrovascular beds, randomized trials in perioperative populations, and meta-analyses. The literature was summarized to guide therapy in the population of vascular patients and for the perioperative period.

RESULTS

National standards for glycemic control after vascular interventions were not identified. Mounting evidence exists for the long-term consequences of poor glycemic control on the progression of vascular disease. Similarly, there is a large body of evidence supporting tight control of hyperglycemia after general and cardiac surgery during the critical perioperative period. The absolute glucose target remains controversial. Randomized controlled studies are lacking in vascular surgery patients, but the current evidence can be extrapolated to guide management after vascular interventions. Glycated hemoglobin is a biomarker for increased mortality and vascular morbidity after vascular surgery.

CONCLUSIONS

Hyperglycemia contributes to poor outcome in the vascular patient. Further vascular focused studies are required to determine the proper perioperative serum glucose target and the long-term glycated hemoglobin range.

Treating hyperglycemia in neurocritical patients: benefits and perils

There is growing debate over the value of intensive insulin therapy (IIT) in critically ill patients. Available trials have been performed in general medical or surgical intensive care units, and the results may not be directly applicable to patients with severe acute brain disease because these patients may have heightened susceptibility to hyperglycemia (HyperG) and hypoglycemia. Our objective was to review the pathophysiology and effects of HyperG and hypoglycemia in neurocritical patients and to analyze the potential role of IIT in this population. Source data were obtained from a PubMed search of the medical literature combining the terms HyperG, hypoglycemia, insulin, stroke, intracerebral hemorrhage (ICH), subarachnoid hemorrhage (SAH), traumatic brain injury (TBI), spinal cord injury (SCI), and related diagnoses. Brain metabolism is highly dependent on constant supply of glucose. As a consequence, the acutely injured brain is particularly sensitive to hypoglycemia, which can induce a state of energy failure (metabolic crisis). Meanwhile, neurocritical patients have a high prevalence of HyperG, and its occurrence is associated with poor outcome after acute ischemic stroke, ICH, SAH, and TBI. It is unclear whether this association is due to direct detrimental effects exerted by HyperG or simply represents a marker of severe brain injury. Insulin has been shown to have various potentially pleiotropic neuroprotective properties in experimental models. However, the safety and efficacy of IIT in patients with critical brain disease have not been well studied. Available results do not support the use of IIT to maintain strict normoglycemia in this population. Patients with critical brain disease should have frequent glucose monitoring because severe HyperG and even modest hypoglycemia may be detrimental. Careful use of insulin infusion protocols appears advisable, but maintenance of strict normoglycemia cannot be recommended. Rigorous studies must be conducted to assess the value of insulin therapy and to determine the optimal blood glucose targets in patients with the most common acute vascular and traumatic brain insults.

Treatment of diving emergencies

Recognition of condition attributable to the environmental changes experienced by divers will facilitate appropriate treatment. The diagnosis of these conditions rarely requires sophisticated imaging or electrophysiologic testing. Divers who have suspected DCI, in addition to general supportive measures, should be administered fluids and oxygen and transported to a recompression chamber. For diving-related conditions, on-line consultation is available from the Divers Alert Network, Durham, NC (919-684-8111).