Insulin resistance increases before ventilator-associated pneumonia in euglycemic trauma patients

Impact of prolonged requirement for insulin on 90-day mortality in critically ill patients without previous diabetic treatments: a post hoc analysis of the CONTROLING randomized control trial

BACKGROUND

Stress hyperglycemia can persist during an intensive care unit (ICU) stay and result in prolonged requirement for insulin (PRI). The impact of PRI on ICU patient outcomes is not known. We evaluated the relationship between PRI and Day 90 mortality in ICU patients without previous diabetic treatments.

METHODS

This is a post hoc analysis of the CONTROLING trial, involving 12 French ICUs. Patients in the personalized glucose control arm with an ICU length of stay ≥ 5 days and who had never previously received diabetic treatments (oral drugs or insulin) were included. Personalized blood glucose targets were estimated on their preadmission usual glycemia as estimated by their glycated A1c hemoglobin (HbA1C). PRI was defined by insulin requirement. The relationship between PRI on Day 5 and 90-day mortality was assessed by Cox survival models with inverse probability of treatment weighting (IPTW). Glycemic control was defined as at least one blood glucose value below the blood glucose target value on Day 5.

RESULTS

A total of 476 patients were included, of whom 62.4% were male, with a median age of 66 (54-76) years. Median values for SAPS II and HbA1C were 50 (37.5-64) and 5.7 (5.4-6.1)%, respectively. PRI was observed in 364/476 (72.5%) patients on Day 5. 90-day mortality was 23.1% in the whole cohort, 25.3% in the PRI group and 16.1% in the non-PRI group (p < 0.01). IPTW analysis showed that PRI on Day 5 was not associated with Day 90 mortality (_IPTWHR = 1.22; CI 95% 0.84-1.75; p = 0.29), whereas PRI without glycemic control was associated with an increased risk of death at Day 90 (_IPTWHR = 3.34; CI 95% 1.26-8.83; p < 0.01).

CONCLUSION

In ICU patients without previous diabetic treatments, only PRI without glycemic control on Day 5 was associated with an increased risk of death. Additional studies are required to determine the factors contributing to these results.

Prevention of VAP: Endless evolving evidences-systematic literature review

INTRODUCTION

Prevention of ventilator associated pneumonia (VAP) is the focus in critical care units. Immunocompromised patients, older adults, and postoperative patients are at greater risk for VAP. With the dynamic changes in the empirical world, updated evidence must be used to guide the standard of practice. This literature review assimilates the recent evidence for VAP prevention.

METHOD

The Preferred Reporting Items for Systematic Reviews and Meta-analysis framework guided the selection of the included research articles. Medline, EBSCO host, CINAHL, UpToDate and Google Scholar databases explored, for relevant publications between 2010 and 2020. The quality of evidence for the 14 studies selected were rated using the hierarchy of quantitative research designs.

RESULTS

Evidence-based VAP preventive strategies are prevention of aspiration, minimizing ventilator days, reducing the pathogen load, safe endotracheal suction practices, and pharmaceutical preventive measures. The mandates for VAP preventive measures among coronavirus disease 2019 (COVID-19) patients is included.

CONCLUSION

Though some of these themes identify with the past, the nuances in their implementation are highlights of this review. The review reiterates the need to revisit ambiguous practices implemented for VAP prevention. Adherence to evidence-based practices, by education, training, and reduction of workload is the key to VAP prevention.

Effect of multimodal analgesia on perioperative insulin resistance in patients with colon cancer

Background

High risk of post-surgery complications have always been related with uncontrolled blood glucose, while the relationship between blood glucose and analgesia has not been compared on radical resection of colon cancer. The aim of this study is to investigate the effects of multimodal analgesia on perioperative insulin resistance in patients undergoing radical resection of colon cancer.

Methods

Sixty patients with colon cancer scheduled for radical resection surgery were equally divided into two groups randomly, the control group (TAP group) received general anesthesia and the transversus abdominis plane block analgesia, and the experimental group (GEA group) received extra epidural anesthesia. The analgesic efficacy was evaluated with visual analog scale (VAS). Insulin resistance indicators like fasting plasma glucose (FPG), resistin (RESIS), fasting insulin (FINS), homeostasis model assessment (HOMA) levels, and inflammation indicator interleukin-6 (IL-6) were evaluated during the surgery.

Results

IL-6 increase was significant in the TAP group than that in GEA group (P < 0.01). The insulin resistance increased significantly in TAP group than that in GEA group including HOMA (P < 0.05) and FPG (P < 0.05). There was no significant difference in RESIS levels and VAS scores in the two groups.

Conclusion

Epidural anesthesia leads to less inflammation in radical resection of colon cancer and the insulin level and insulin resistance increased after the surgeries based on FINS and HOMA..

Prospective evaluation of metabolic syndrome and its features in a single-center series of hematopoietic stem cell transplantation recipients

Available studies on metabolic syndrome (MS) after hematopoietic stem cell transplantation (HSCT) are retrospective with heterogeneous inclusion criteria, and little is known about the early post-transplant phase. In our prospective study, clinical and laboratory data were collected in 100 HSCT recipients, 48 allogeneic and 52 autologous, at baseline, at + 30, + 100 and + 360 days. At baseline, MS was observed in 24 patients, significantly associated with insulin resistance and leptin on multivariate analysis. At + 30, the diagnosis of MS was confirmed in 43 patients, significantly related to insulin resistance and allogeneic transplants. If the whole series was considered, patients with MS had significantly higher mortality from any cause. The baseline presence of any MS feature was a predictor of + 30 MS. Isolated occurrences of MS features were related to hyperleptinemia and hyperinsulinemia, except in the case of low HDL cholesterol, linked to adiponectin and resistin. Our data confirm that patients undergoing HSCT have a high prevalence of MS, with hyperleptinemia playing a major role. The early peak of new MS cases is primarily attributable to insulin resistance, notably but not exclusively immunosuppression-induced; the subsequent long-term increase in MS cases may be an effect of persistent adipokine imbalance.

The clinical significance of hyperglycemia in nondiabetic critically ill multiple trauma patients

BACKGROUND

Information is inconsistent regarding the clinical role of acute elevations of blood glucose level secondary to hospital-acquired infections in nondiabetic critically ill patients during an intensive care unit stay. In this study we investigated the clinical significance of hyperglycemia related to new episodes of ventilator-associated pneumonia in nondiabetic critically ill multiple trauma intensive care unit patients.

MATERIALS AND METHODS

We analyzed the clinical data of 202 critically ill multiple trauma patients with no history of previous diabetes who developed a new ventilator-associated pneumonia episode during their intensive care unit stay. We used a time-from-event analysis method to assess whether acute changes in blood glucose levels that occurred prior to the onset of ventilator-associated pneumonia episodes had a different prognostic significance from those that occurred during such episodes. Glucose levels and other laboratory data were recorded for up to 5 days before ventilator-associated pneumonia events and for 5 days following these events.

RESULTS

Patients who required insulin therapy for persistent hyperglycemia related to a new ventilator-associated pneumonia event had a longer period of intensive care unit stay and a higher intensive care unit mortality rate than patients who did not require insulin for blood glucose control (p < 0.008 and <0.001 respectively). In addition, older age, administration of parenteral nutrition, and elevated mean blood glucose level parameters on the day following the day of diagnosis of a new ventilator-associated pneumonia episode were found to be independent risk factors for intensive care unit mortality.

CONCLUSION

Our study suggests that persistent hyperglycemia in nondiabetic critically ill patients, even treated by early insulin therapy, is an adverse prognostic factor of considerable clinical significance.

Higher Mortality in Trauma Patients Is Associated with Stress-Induced Hyperglycemia, but Not Diabetic Hyperglycemia: A Cross-Sectional Analysis Based on a Propensity-Score Matching Approach

Background: Stress-induced hyperglycemia (SIH) is a form of hyperglycemia secondary to stress and commonly occurs in patients with trauma. Trauma patients with SIH have been reported to have an increased risk of mortality. However, information regarding whether these trauma patients with SIH represent a distinct group with differential outcomes when compared to those with diabetic hyperglycemia (DH) remains limited. Methods: Diabetes mellitus (DM) was determined by patient history and/or admission glycated hemoglobin (HbA1c) ≥6.5%. Non-diabetic normoglycemia (NDN) was determined by a serum glucose level <200 mg/dL in the patients without DM. Diabetic normoglycemia (DN) was determined by a serum glucose level <200 mg/dL in the patients with DM. DH and SIH was diagnosed by a serum glucose level ≥200 mg/dL in the patients with and without DM, respectively. Detailed data of these four groups of hospitalized patients, which included NDN (n = 7806), DN (n = 950), SIH (n = 493), and DH (n = 897), were retrieved from the Trauma Registry System at a level I trauma center between 1 January 2009 and 31 December 2015. Patients with incomplete registered data were excluded. Categorical data were compared with Pearson chi-square tests or two-sided Fisher exact tests. The unpaired Student's t-test and the Mann-Whitney U-test were used to analyze normally distributed continuous data and non-normally distributed data, respectively. Propensity-score-matched cohorts in a 1:1 ratio were allocated using NCSS software with logistic regression to evaluate the effect of SIH and DH on the outcomes of patients. Results: The SIH (median [interquartile range: Q1-Q3], 13 [9-24]) demonstrated a significantly higher Injury Severity Score (ISS) than NDN (9 [4-10]), DN (9 [4-9]), and DH (9 [5-13]). SIH and DH had a 12.3-fold (95% confidence interval [CI] 9.31-16.14; p < 0.001) and 2.4-fold (95% CI 1.71-3.45; p < 0.001) higher odds of mortality, respectively, when compared to NDN. However, in the selected propensity-score-matched patient population, SIH had a 3.0-fold higher odd ratio of mortality (95% CI 1.96-4.49; p < 0.001) than NDN, but DH did not have a significantly higher mortality (odds ratio 1.2, 95% CI 0.99-1.38; p = 0.065). In addition, SIH had 2.4-fold higher odds of mortality (95% CI 1.46-4.04; p = 0.001) than DH. These results suggest that the characteristics and injury severity of the trauma patients contributed to the higher mortality of these patients with hyperglycemia upon admission, and that the pathophysiological effect of SIH was different from that of DH. Conclusions: Although there were worse mortality outcomes among trauma patients presenting with hyperglycemia, this effect was only seen in patients with SIH, but not DH when controlling for age, sex, pre-existed co-morbidities, and ISS.

Supplemental Parenteral Nutrition Is the Key to Prevent Energy Deficits in Critically Ill Patients

This review emphasizes the role of a timely supplemental parenteral nutrition (PN) for critically ill patients. It contradicts the recommendations of current guidelines to avoid the use of PN, as it is associated with risk. Critical illness results in severe metabolic stress. During the early phase, inflammatory cytokines and mediators induce catabolism to meet the increased body energy demands by endogenous sources. This response is not suppressed by exogenous energy administration, and the early use of PN to reach the energy target leads to overfeeding. On the other hand, early and progressive enteral nutrition (EN) is less likely to cause overfeeding because of variable gastrointestinal tolerance, a factor frequently associated with significant energy deficit. Recent studies demonstrate that adequate feeding is beneficial during and after the intensive care unit (ICU) stay. Supplemental PN allows for timely adequate feeding, if sufficient precautions are taken to avoid overfeeding. Indirect calorimetry can precisely define the adequate energy prescription. Our pragmatic approach is to start early EN to progressively test the gut tolerance and add supplemental PN on day 3 or 4 after ICU admission, only if EN does not meet the measured energy target. We believe that supplemental PN plays a pivotal role in the achievement of adequate feeding in critically ill patients with intolerance to EN and does not cause harm if overfeeding is avoided by careful prescription, ideally based on energy expenditure measured by indirect calorimetry.

Simulation and qualitative analysis of glucose variability, mean glucose, and hypoglycemia after subcutaneous insulin therapy for stress hyperglycemia

Background

The critically ill can have persistent dysglycemia during the “subacute” recovery phase of their illness because of altered gene expression; it is also not uncommon for these patients to receive continuous enteral nutrition during this time. The optimal short-acting subcutaneous insulin therapy that should be used in this clinical scenario, however, is unknown. Our aim was to conduct a qualitative numerical study of the glucose-insulin dynamics within this patient population to answer the above question. This analysis may help clinicians design a relevant clinical trial.

Methods

Eight virtual patients with stress hyperglycemia were simulated by means of a mathematical model. Each virtual patient had a different combination of insulin resistance and insulin deficiency that defined their unique stress hyperglycemia state; the rate of gluconeogenesis was also doubled. The patients received 25 injections of subcutaneous regular or Lispro insulin (0-6 U) with 3 rates of continuous nutrition. The main outcome measurements were the change in mean glucose concentration, the change in glucose variability, and hypoglycemic episodes. These end points were interpreted by how the ultradian oscillations of glucose concentration were affected by each insulin preparation.

Results

Subcutaneous regular insulin lowered both mean glucose concentrations and glucose variability in a linear fashion. No hypoglycemic episodes were noted. Although subcutaneous Lispro insulin lowered mean glucose concentrations, glucose variability increased in a nonlinear fashion. In patients with high insulin resistance and nutrition at goal, “rebound hyperglycemia” was noted after the insulin analog was rapidly metabolized. When the nutritional source was removed, hypoglycemia tended to occur at higher Lispro insulin doses. Finally, patients with severe insulin resistance seemed the most sensitive to insulin concentration changes.

Conclusions

Subcutaneous regular insulin consistently lowered mean glucose concentrations and glucose variability; its linear dose-response curve rendered the preparation better suited for a sliding-scale protocol. The longer duration of action of subcutaneous regular insulin resulted in better glycemic-control metrics for patients who were continuously postprandial. Clinical trials are needed to examine whether these numerical results represent the glucose-insulin dynamics that occur in intensive care units; if present, their clinical effects should be evaluated.

NF-κB-dependent airway inflammation triggers systemic insulin resistance

Inflammatory lung diseases (e.g., pneumonia and acute respiratory distress syndrome) are associated with hyperglycemia, even in patients without a prior diagnosis of Type 2 diabetes. It is unknown whether the lung inflammation itself or the accompanying comorbidities contribute to the increased risk of hyperglycemia and insulin resistance. To investigate whether inflammatory signaling by airway epithelial cells can induce systemic insulin resistance, we used a line of doxycycline-inducible transgenic mice that express a constitutive activator of the NF-κB in airway epithelial cells. Airway inflammation with accompanying neutrophilic infiltration was induced with doxycycline over 5 days. Then, hyperinsulinemic-euglycemic clamps were performed in chronically catheterized, conscious mice to assess insulin action. Lung inflammation decreased the whole body glucose requirements and was associated with secondary activation of inflammation in multiple tissues. Metabolic changes occurred in the absence of hypoxemia. Lung inflammation markedly attenuated insulin-induced suppression of hepatic glucose production and moderately impaired insulin action in peripheral tissues. The hepatic Akt signaling pathway was intact, while hepatic markers of inflammation and plasma lactate were increased. As insulin signaling was intact, the inability of insulin to suppress glucose production in the liver could have been driven by the increase in lactate, which is a substrate for gluconeogenesis, or due to an inflammation-driven signal that is independent of Akt. Thus, localized airway inflammation that is observed during inflammatory lung diseases can contribute to systemic inflammation and insulin resistance.

Insulin Resistance in Critically Injured Adults: Contribution of Pneumonia, Diabetes, Nutrition, and Acuity

PURPOSE

Changes in insulin resistance (IR) cause stress-induced hyperglycemia after trauma, but the numerous factors involved in IR have not been delineated clearly. We hypothesized that a statistical model could help determine the relative contribution of different clinical co-variates to IR in critically injured patients.

PATIENTS AND METHODS

We retrospectively studied 726 critically injured patients managed with a computer-assisted glycemic protocol at an academic level I trauma center (639 ventilated controls without pneumonia (VWP) and 87 patients with ventilator-associated pneumonia (VAP). Linear regression using age, gender, body mass index (BMI), diabetes mellitus, pneumonia, and glycemic provision was used to estimate M, a marker of IR that incorporates both the serum blood glucose concentration (BG) and insulin dose.

RESULTS

Increasing M (p<0.001) was associated with age (1.62%; 95% confidence interval [CI] 1.27%-1.97% per decade), male gender (9.78%; 95% CI 8.28%-12.6%), BMI (4.32% [95% CI 4.02%-4.62%] per 5 points), diabetes mellitus (21.2%; 95% CI 19.2%-23.2%), pneumonia (10.9%; 95% CI 9.31%-12.6%), and glycemic provision (27.3% [95% CI 6.6%-28.1%] per 100 g of glucose). Total parenteral nutrition was associated with a decrease in M of 10.3%; 95% CI 8.52%-12.1%; p<0.001.

CONCLUSIONS

Clinical factors can be used to construct a model of IR. Prospective validation might enable early detection and treatment of infection or other conditions associated with increased IR.