Predictors of insulin requirements among hospitalized adults receiving parenteral nutrition

Behavior of Regular Insulin in a Parenteral Nutrition Admixture: Validation of an LC/MS-MS Assay and the In Vitro Evaluation of Insulin Glycation

Parenteral-nutrition (PN)-induced hyperglycemia increases morbidity and mortality and must be treated with insulin. Unfortunately, the addition of insulin to a ternary PN admixture leads to a rapid decrease in insulin content. Our study's objective was to determine the mechanistic basis of insulin's disappearance. The literature data suggested the presence of a glycation reaction; we therefore validated an LC-MS/MS assay for insulin and glycated insulin. In a 24-h stability study, 20 IU/L of insulin was added to a binary PN admixture at pH 3.6 or 6.3. When the samples were diluted before analysis with a near-neutral diluent, insulin was fully stable at pH 3.6, while a loss of around 50% was observed at pH 6.3. Its disappearance was shown to be inversely correlated with the appearance of monoglycated insulin (probably a Schiff base adduct). Monoglycated insulin might also undergo a back-reaction to form insulin after acidic dilution. Furthermore, a second monoglycated insulin species appeared in the PN admixture after more than 24 h at high temperature (40 °C) and a high insulin concentration (1000 IU/L). It was stable at acidic pH and might be an Amadori product. The impact of insulin glycation under non-forced conditions on insulin's bioactivity requires further investigation.

The Impact and Clinical Prediction of Hyperglycemia During Parenteral Nutrition for Nondiabetic Patients After Gastrectomy for Gastric Cancer

Background and Purpose

Hyperglycemia (HG) is associated with increased postoperative complications. This study aims to evaluate the effect of HG during supplemental parenteral nutrition (SPN) on short-term prognosis in non-diabetic patients undergoing gastrectomy for cancer and to analyse the risk factors and prevention methods for HG.

Methods

A total of 359 patients were divided into three groups according to blood glucose (BG) during SPN: normoglycemic patients ( ≤ 125 mg/dL), mild HG (125~200 mg/dL), and severe HG (>200 mg/dL). The effect of BG on postoperative short-term outcomes was analyzed. Multivariate regression was performed to investigate influencing factors for severe HG. The safety and efficacy of insulin addition to total nutrient admixture (TNA) for the prevention and management of HG were assessed by propensity score matching (PSM). In addition, regression analysis was performed in the noninsulin group to investigate the predictive factors of severe HG, and a nomogram was plotted.

Results

The postoperative complication rate was 18.9%, but it was significantly higher in patients with severe HG than in mild HG and normoglycemic patients (25.2, 15.0, and 10.0%, respectively, p < 0.05). Multivariate logistic regression analysis showed that anemia, myosteatosis, higher postoperative capillary blood glucose (CBG) before TNA infusion, and insulin in the TNA were independent influencing factors for severe HG. Based on the above factors, 75 pairs of patients (insulin group and non-insulin group) with comparable baseline data were successfully matched by PSM. The HG incidence and the glycemic fluctuation were significantly improved through 1 U insulin/6 g glucose (1/6 scheme) to TNA. A nomogram containing hemoglobin, skeletal muscle radiodensity, pre-SPN CBG, and pTNM stage with good predictive efficacy (C-index: 0.750) was constructed based on the noninsulin group.

Conclusion

Poor postoperative glycemic control was related to worse outcomes in non-diabetic patients undergoing gastrectomy for cancer. Pre-operative anemia, myosteatosis, and high postoperative CBG before TNA infusion are risk factors for severe HG. Insulin in TNA can improve the blood glucose control of patients. Our proposed nomogram rendered an individualized predictive tool for HG during SPN, which helps screen high-risk patients requiring insulin therapy. Future studies with larger samples are needed to develop a complete insulin application protocol for SPN.

Addition of Regular Insulin to Ternary Parenteral Nutrition: A Stability Study

Background: Parenteral nutrition (PN) is a complex medium in which added insulin can become unstable. The aim of this study is, therefore, to evaluate the stability of insulin in PN and to identify influencing factors. Methods: A total of 20 IU/L of regular insulin was added to PN in either glass or Ethylene Vinyl Acetate (EVA) containers. A 24 h stability study was performed via an electrochemiluminescence immunoassay in different media: A ternary PN admixture, separate compartments of the PN bag and a binary admixture. This study was repeated in the absence of zinc, with the addition of serum albumin or tween and with pH adjustment (3.6 or 6.3). Insulin concentration at t time was expressed as a percentage of the initial insulin concentration. Analysis of covariance (ANCOVA) was applied to determine the factors that influence insulin stability. Results: In all PN admixtures, the insulin concentration ratio decreased, stabilising at a 60% and then plateauing after 6 h. At pH 3.6, the ratio was above 90%, while at pH 6.3 it decreased, except in the amino acid solution. ANCOVA (r² = 0.68, p = 0.01) identified dextrose and pH as significant factors influencing insulin stability. Conclusion: A low pH level seems to stabilise insulin in PN admixtures. The influence of dextrose content suggests that insulin glycation may influence stability.

Prevalence and Risk Factors of Total Parenteral Nutrition Induced Hyperglycemia at a Single Institution: Retrospective Study

Background: Total parenteral nutrition (TPN) provides full nutrition support to critically ill patients with an impaired digestive tract. Patients who receive TPN support are at higher risk for complications such as hyperglycemia. In our study, we aim to assess the prevalence of hyperglycemia induced by TPN and identify its risk factors in hospitalized adult patients. Methods: Patients who received TPN between January 2012 and December 2017 at University of Pittsburgh Medical Center-St. Margaret hospital were retrospectively screened. TPN-induced hyperglycemia was confirmed whether blood glucose was ≥180 mg/dL at any point, from the time of TPN initiation until 1-day post TPN termination. Characteristics of the hyperglycemia and the nonhyperglycemia groups were analyzed to predict potential risk factors. Results: A total of 197 patients were screened, 55 were excluded (1 died, 37 diabetic, and 17 had elevated blood glucose before TPN), and 142 patients were included, 42 of them (29.6%) developed hyperglycemia following TPN administration. Duration of TPN, surgical indications, and obesity were significantly higher in the hyperglycemia group. Additionally, age and steroids use were independent predictors of hyperglycemia in TPN patients after applying multivariable logistic regression model on our sample. Conclusions: Hyperglycemia is common after TPN. Risk factors assessment may help optimizing glycemic control in higher risk individuals to improve their outcomes. These include patients with obesity, surgical indication of TPN, and longer duration of TPN.

THE MANAGEMENT OF HYPERGLYCEMIA IN NONCRITICALLY ILL HOSPITALIZED PATIENTS TREATED WITH CONTINUOUS ENTERAL OR PARENTERAL NUTRITION

OBJECTIVE

Hyperglycemia is a common problem in hospitalized patients receiving artificial nutrition, and this development of hyperglycemia during parenteral nutrition therapy (PNT) and enteral nutrition therapy (ENT) increases the risks of hospital-related complications and mortality. This review aims to discuss the pathogenesis of hyperglycemia from artificial nutrition in the hospital, summarize current evidence on the treatment of hyperglycemia with insulin in these patients, and review current guidelines.

METHODS

A systematic literature review using PubMed and the Medical Subject Headings (MeSH) terms "hyperglycemia," "enteral nutrition," and "parenteral nutrition" were used to evaluate the current evidence available for treating noncritically ill patients with hyperglycemia who were receiving artificial nutrition.

RESULTS

The literature review showed that few randomized control trials exist regarding treatment of hyperglycemia in this cohort of patients, and the multiple retrospective evaluations that have addressed this topic provided varied results. In general, intravenous (IV) continuous insulin infusion offers the best glycemic control; however, this route of insulin administration is often burdensome for floor patients and their care teams. Administration of scheduled subcutaneous (SQ) insulin in patients on ENT or PNT is a safe and effective way to manage hyperglycemia, however limited data exist on an appropriate insulin regimen.

CONCLUSION

Further prospective, randomized control trials are necessary to determine the optimal treatment of hyperglycemia for patients receiving ENT or PNT.

ABBREVIATIONS

BG = blood glucose; CG = conventional glycemic control; ENT = enteral nutrition therapy; GIP = glucose-dependent insulinotropic polypeptide; GLP-1 = glucagon-like peptide 1; IG = intensive glycemic control; IV = intravenous; NPH = neutral protamine Hagedorn; PNT = parenteral nutrition therapy; SQ = subcutaneous; T2DM = type 2 diabetes mellitus; TDD = total daily dose; TPN = total parenteral nutrition.

Management of hospitalized type 2 diabetes mellitus patients

Both hyperglycemia and hypoglycemia in hospitalized patients are associated with adverse outcomes including increased rates of infection, longer hospital length of stay, and even death. Clinical trials in patients with type 2 diabetes mellitus proved that by improving glycemic control, we can reduce all of them. Insulin is the preferred treatment for glycemic control in most cases, but alternative treatment options that can normalize blood glucose levels without hypoglycemia are being sought. Moreover, hospitalized patients are particularly vulnerable to severe, prolonged hypoglycemia since they may be unable to sense or respond to the early warning signs and symptoms of low blood glucose. Finally, nutritional support, corticosteroid therapy, and surgery increase the risk of hyperglycemia that leads to an increased risk of morbidity and mortality. We review the management of type 2 diabetes mellitus patients who are admitted to the general medical wards of the hospital for a procedure of intercurrent illness.

Prevalence of diabetes, prediabetes, and stress hyperglycemia: insulin therapy and metabolic control in patients on total parenteral nutrition (prospective multicenter study)

OBJECTIVE

The prevalence of carbohydrate metabolism disorders in patients who receive total parenteral nutrition (TPN) is not well known. These disorders can affect the treatment, metabolic control, and prognosis of affected patients. The aims of this study were to determine the prevalence in noncritically ill patients on TPN of diabetes, prediabetes, and stress hyperglycemia; the factors affecting hyperglycemia during TPN; and the insulin therapy provided and the metabolic control achieved.

METHODS

We undertook a prospective multicenter study involving 19 Spanish hospitals. Noncritically ill patients who were prescribed TPN were included, and data were collected on demographic, clinical, and laboratory variables (glycated hemoglobin, C-reactive protein [CRP], capillary blood glucose) as well as insulin treatment.

RESULTS

The study included 605 patients. Before initiation of TPN, the prevalence of known diabetes was 17.4%, unknown diabetes 4.3%, stress hyperglycemia 7.1%, and prediabetes 27.8%. During TPN therapy, 50.9% of patients had at least one capillary blood glucose of >180 mg/dL. Predisposing factors were age, levels of CRP and glycated hemoglobin, the presence of diabetes, infectious complications, the number of grams of carbohydrates infused, and the administration of glucose-elevating drugs. Most (71.6%) patients were treated with insulin. The mean capillary blood glucose levels during TPN were: known diabetes (178.6 ± 46.5 mg/dL), unknown diabetes (173.9 ± 51.9), prediabetes (136.0 ± 25.4), stress hyperglycemia (146.0 ± 29.3), and normal (123.2 ± 19.9) (P<.001).

CONCLUSION

The prevalence of carbohydrate metabolism disorders is very high in noncritically ill patients on TPN. These disorders affect insulin treatment and the degree of metabolic control achieved.

Post-Transplant Diabetes Mellitus: Causes, Treatment, and Impact on Outcomes

Post-transplant diabetes mellitus (PTDM) is a frequent consequence of solid organ transplantation. PTDM has been associated with greater mortality and increased infections in different transplant groups using different diagnostic criteria. An international consensus panel recommended a consistent set of guidelines in 2003 based on American Diabetes Association glucose criteria but did not exclude the immediate post-transplant hospitalization when many patients receive large doses of corticosteroids. Greater glucose monitoring during all hospitalizations has revealed significant glucose intolerance in the majority of recipients immediately after transplant. As a result, the international consensus panel reviewed its earlier guidelines and recommended delaying screening and diagnosis of PTDM until the recipient is on stable doses of immunosuppression after discharge from initial transplant hospitalization. The group cautioned that whereas hemoglobin A1C has been adopted as a diagnostic criterion by many, it is not reliable as the sole diabetes screening method during the first year after transplant. Risk factors for PTDM include many of the immunosuppressant medications themselves as well as those for type 2 diabetes. The provider managing diabetes and associated dyslipidemia and hypertension after transplant must be careful of the greater risk for drug-drug interactions and infections with immunosuppressant medications. Treatment goals and therapies must consider the greater risk for fluctuating and reduced kidney function, which can cause hypoglycemia. Research is actively focused on strategies to prevent PTDM, but until strategies are found, it is imperative that immunosuppression regimens are chosen based on their evidence to prolong graft survival, not to avoid PTDM.

Effectiveness of regular versus glargine insulin in stable critical care patients receiving parenteral nutrition: a randomized controlled trial

STUDY OBJECTIVE

To compare the effectiveness and safety of two glycemic control regimens in stable critical care patients receiving parenteral nutrition (PN).

DESIGN

Prospective, randomized open-label clinical trial.

METHODS

Eligible postoperative critical care patients in the ICU began PN on the first to the seventh day of ICU admission. The PN admixture included regular insulin, in doses sufficient to maintain 3 or more goal blood glucose (BG) levels between 110 and 180 mg/dl. After 3 to 5 days of PN containing regular insulin, patients were randomized to 3 more days of regular insulin at the same dose or 80% of their total daily regular insulin dose provided in PN solution as glargine insulin. Capillary BG monitoring was performed every 6 hours.

RESULTS

Twenty one patients were randomized to each treatment group. Median APACHE II scores were not significantly different between the two groups within the first 24-hour of ICU admission. There were no significant differences between the two groups at day 3 for mean daily dextrose (306.9 ± 46.2 vs. 305.2 ± 52.2 g; p=0.913) or insulin (18.3 ± 8.8 vs. 19.5 ± 10.0 units; p=0.696) doses. The percentage of BG values in the goal (110-180 mg/dl), hyperglycemic (> 180 mg/dl), and hypoglycemic (< 70 mg/dl) BG levels were similar between the two groups (69.0% vs. 66.7%, p=0.567; 11.9% vs. 11.1%, p=0.780; 0% vs. 1.6%, p=0.124, respectively). Mean daily BG levels were not significantly different between the two groups on each of the 3 study days (day 1: 140 ± 20 vs. 131 ± 25 mg/dl, p=0.194; day 2: 136 ± 20 vs. 140 ± 18 mg/dl, p=0.498; day 3: 142 ± 15 vs. 140 ± 19 mg/dl; p=0.741).

CONCLUSION

These data suggest that, compared with regular insulin added to PN, glargine insulin results in similar glycemic control and rates of hyperglycemia and hypoglycemia in stable critical care patients.

Management of the hospitalized transplant patient

Significant hyperglycemia is commonly observed immediately after solid organ and bone marrow transplant as well as with subsequent hospitalizations. Surgery and procedures are well known to cause pain and stress leading to secretion of cytokines and other hormones known to aggravate insulin action. Immunosuppression required for transplant and preexisting risk are also major factors. Glucose control improves outcomes for all hospitalized patients, including transplant patients, but is often more challenging to achieve because of frequent and sometimes unpredictable changes in immunosuppression doses, renal function, and nutrition. As a result, risk of hypoglycemia can be greater in this patient group when trying to achieve glucose control goals for hospitalized patients. Key to successful management of hyperglycemia is regular communication between the members of the care team as well as anticipating and rapidly implementing a new treatment paradigm in response to changes in immunosuppression, nutrition, renal function, or evidence of changing insulin resistance.