Optimal glycemic control in neurocritical care patients

Safety and Efficacy of Continuous or Intermittent Enteral Nutrition in ICU Patients: Systematic Review of Clinical Evidence

The best mode of delivering enteral nutrition (EN) in ICU is still debated: several consensus guidelines (ASPEN and ESPEN) suggest that EN in ICU should be preferably delivered continuously rather intermittently but some authors highlight that the first is unphysiological. The aim of this systematic review (SR) is to summarize available clinical evidence related to safety and efficacy of continuous enteral nutrition (C-EN) or intermittent enteral nutrition (I-EN) in ICU patients, in relation to appropriated supply on nutritional status, gastrointestinal symptoms or tolerance, risks on respiratory tract infections. A literature search of Pubmed, EMBASE and Google Scholar was performed comparing C-EN vs I-EN and 4196 published studies were screened. Nineteen studies were selected for this SR reporting types of ICU, nutritional protocols and study period. Effects of C-EN vs I-EN were presented according to the impact on: nutritional status, digestive tract and respiratory tract. The contrasting results confirmed that the optimal delivering mode of EN remains controversial. Future studies dedicated to identify the benefits and limitations of C-EN or I-EN should be realized. This article is protected by copyright. All rights reserved.

Perioperative Glycemia Management in Patients Undergoing Craniotomy for Brain Tumor Resection: A Global Survey of Neuroanesthesiologists' Perceptions and Practices

OBJECTIVE

There is a paucity of clinical evidence that guides perioperative glycemia management in patients undergoing craniotomy for brain tumor resection. The purpose of this study was to better understand global perceptions and practices related to glycemia management in these patients.

METHODS

Neuroanesthesiologists throughout North America, South America, Europe, and Asia filled out a brief online questionnaire related to their perceptions and practices regarding glycemia management in patients undergoing craniotomy for brain tumor resection.

RESULTS

Over 4 weeks, 435 participants practicing in 34 countries across 6 continents participated in this survey. Although responders in North America were found to perceive a higher risk hyperglycemia compared with those practicing in European (P = 0.024) and South Asian (P = 0.007) countries, responders practicing in South Asian countries (P = 0.030), Middle Eastern countries (P = 0.029), and South American (P = 0.005) countries were more likely than those from North America to remeasure glucose after an initial normal glucose measurement at incision. Responders from North America reported that a higher blood glucose threshold was necessary for them to delay or cancel the surgery compared with responders in Slavic (P < 0.001), European (P = 0.002), South American (P = 0.002), and Asian and Pacific (P < 0.001) countries. Responders from North America were more likely to report that they would delay or cancel the surgery because of a higher blood glucose threshold.

CONCLUSIONS

Our survey results suggest that perceptions and practices related to blood glucose management in patients undergoing brain tumor resection are variable. This study highlights the need for stronger clinical evidence and guidelines to help guide decisions for when and how to manage blood glucose derangements in these patients.

Hypoglycemia in a Surgical Intensive Care Unit

BACKGROUND

Glycemic control is an important aspect of critical care because derangements are associated with morbidity and mortality. Patients at highest risk for hypoglycemia in the surgical intensive care unit (SICU) are incompletely described by existing literature. Our objective was to delineate this high-risk patient population in our SICU.

STUDY DESIGN

In this single-center, retrospective, observational study, SICU patients admitted from June 1, 2019 to July 31, 2020 with ≥1 episode of hypoglycemia (blood glucose <60 mg/dL) were included.

RESULTS

There were 41 hypoglycemic events in 27 patients, comprising an incidence of 1.5% among SICU patients. The most common admission diagnoses were cirrhosis (n = 13, 48%), polytrauma (n = 12, 44%), multisystem organ failure (n = 11, 41%), diabetes mellitus (n = 9, 33%), and soft tissue infection (n = 8, 30%). Four high-risk populations were identified: patients in multisystem organ failure (MSOF) (n = 11, 41%); those who were nil per os (NPO) (n = 10, 37%); patients receiving long acting subcutaneous insulin, for example, Lantus (n = 3, 11%); and those on continuous intravenous insulin infusions (n = 3, 11%). After multi-disciplinary peer review, most hypoglycemic events (n = 16, 59%) were deemed iatrogenic.

CONCLUSIONS

Hypoglycemia is rare in surgical critical care. When it does occur, patients are typically in MSOF, NPO, on long acting subcutaneous insulin or continuous insulin infusions, have soft tissue infections, or have acute or chronic liver failure. Increased vigilance with frequent blood glucose monitoring in these high-risk patients may reduce the risk of hypoglycemia in the SICU.

Sildenafil alters biogenic amines and increases oxidative damage in brain regions of insulin-hypoglycemic rats

The aim of the present study was to determine the effect of sildenafil on dopamine, 5-hydroxyindol acetic acid (5-HIAA) and selected biomarkers of oxidative stress in the brain of hypoglycemic rats. The animals were treated intraperitoneally as follows: group 1 (control), saline solution; group 2, insulin (10 U per rat or 50 U kg-1); group 3, insulin + single dose of sildenafil (50 U kg-1 + 50 mg kg-1); group 4, insulin + three doses of sildenafil every 24 hours (50 U kg-1 + 50 mg kg-1). In groups 2, 3 and 4, insulin was administered every 24 hours for 10 days. Blood glucose was measured after the last treatment. On the last day of the treatment, the animals´ brains were extracted to measure the levels of oxidative stress markers [H2O2, Ca2+,Mg2+-ATPase, glutathione and lipid peroxidation (TBARS)], dopamine and 5-HIAA in the cortex, striatum and cerebellum/medulla oblongata by validated methods. The results suggest that administration of insulin in combination with sildenafil induces hypoglycemia and hypotension, enhances oxidative damage and provokes changes in the brain metabolism of biogenic amines. Administration of insulin and sildenafil promotes biometabolic responses in glucose control, namely, it induces hypoglycemia and hypotension. It also enhances oxidative damage and provokes changes in the brain metabolism of biogenic amines.

Insulin plus zinc induces a favorable biochemical response effects on oxidative damage and dopamine levels in rat brain

The aim was to determine the effect of zinc (Zn) and insulin on oxidative stress and levels of dopamine in brain of rats. Wistar rats were treated either with zinc alone or combined with insulin during 10 days. After the last dose blood glucose was measured. Their brains were extracted to measure H₂O₂, Ca⁺², Mg⁺² ATPase, glutathione (GSH), lipid peroxidation (Tbars) and Dopamine. Zn does not possess anti-glycemic effect like Insulin however, it is noticeable that the combination of Insulin plus Zn induces a major glucose reduction (p < 0.0001) than Insulin alone. In cerebellum/medulla oblongata, the groups treated with Insulin and Zn show a significantly increase in dopamine (p < 0.005). Insulin plus Zn reduced GSH level in cortex. Insulin plus Zn reduced level of H₂O₂ in Striatum and in cerebellum/medulla oblongata. Lipid peroxidation was significantly reduced by the administration of Insulin as in the combination of Insulin and Zn in all regions (p < 0.0001). In cerebellum medulla oblongata, ATPase activity showed an increase only in the group treated with Insulin + Zn. CONCLUSION: These results suggest that the use of insulin plus Zn produce favorable changes on oxidative stress and this as consequence on the levels of dopamine.

Management of hyperglycemia in the neurosurgery patient

Hyperglycemia is associated with adverse outcomes in patients who are candidates for or underwent neurosurgical procedures. Specific concerns and settings that relate to these patients are preoperative glycemic control, intraoperative control, management in the neurological intensive care unit (NICU), and postoperative control. In each of these settings, physicians have to ensure appropriate glycemic control to prevent or minimize adverse events. The glycemic control is usually managed by a neurohospitalist in co-management with the neurosurgery team pre- and post-operatively, and by the neurocritical care team in the setting of NICU. In this review article, we outline current standards of care for neurosurgery patients with diabetes mellitus and/or and hyperglycemia and discuss results of most recent clinical trials. We highlight specific concerns with regards to glycemic controls in these patients including enteral tube feeding and parenteral nutrition, the issues of the transition to the outpatient care, and management of steroid-induced hyperglycemia. We also note lack of evidence in some important areas, and the need for more research addressing these gaps. Where possible, we provide suggestions how to manage these patients when there is no underlying guideline.

Severe Intraoperative Hyperglycemia Is Independently Associated With Postoperative Composite Infection After Craniotomy: An Observational Study

BACKGROUND

Postoperative infection after craniotomy carries an increased risk of morbidity and mortality. Identification and correction of the risk factors should be prioritized. The association of intraoperative hyperglycemia with postoperative infections in patients undergoing craniotomy is inadequately studied.

METHODS

A total of 224 patients were prospectively enrolled in 2 major medical centers to assess whether severe intraoperative hyperglycemia (SIH, blood glucose ≥180 mg/dL) is associated with an increased risk of postoperative infection in patients undergoing craniotomy. Arterial blood samples were drawn and analyzed immediately after anesthetic induction and again before tracheal extubation. The new onset of any type of infection within 7 days after craniotomy was determined.

RESULTS

The incidence of new postoperative composite infection was 10% (n = 22) within the first week after craniotomy. Weight, sex, American Society of Anesthesiologists score, preoperative and/or intraoperative steroid use, and diabetes mellitus were not associated with postoperative infection. SIH was independently associated with postoperative infection (odds ratio [95% confidence interval], 4.17 [1.50-11.56], P = .006) after fitting a multiple logistic regression model to adjust for emergency surgery, length of surgery, and age ≥65 years.

CONCLUSIONS

SIH is independently associated with postoperative new-onset composite infections in patients undergoing craniotomy. Whether prevention of SIH during craniotomy results in a reduced postoperative risk of infection is unknown and needs to be appraised by further study.

International multidisciplinary consensus conference on multimodality monitoring: ICU processes of care

There is an increased focus on evaluating processes of care, particularly in the high acuity and cost environment of intensive care. Evaluation of neurocritical-specific care and evidence-based protocol implementation are needed to effectively determine optimal processes of care and effect on patient outcomes. General quality measures to evaluate intensive care unit (ICU) processes of care have been proposed; however, applicability of these measures in neurocritical care populations has not been established. A comprehensive literature search was conducted for English language articles from 1990 to August 2013. A total of 1,061 articles were reviewed, with 145 meeting criteria for inclusion in this review. Care in specialized neurocritical care units or by neurocritical teams can have a positive impact on mortality, length of stay, and in some cases, functional outcome. Similarly, implementation of evidence-based protocol-directed care can enhance outcome in the neurocritical care population. There is significant evidence to support suggested quality indicators for the general ICU population, but limited research regarding specific use in neurocritical care. Quality indices for neurocritical care have been proposed; however, additional research is needed to further validate measures.

Standards of scoring, monitoring, and parameter targeting in German neurocritical care units: a national survey

BACKGROUND

Optimal management of physiological parameters in neurological/neurosurgical intensive care units (NICUs) is largely unclear as high-quality evidence is lacking. The aim of this survey was to investigate if standards exist in the use of clinical scores, systemic and cerebral monitoring and the targeting of physiology values and in what way this affects clinical management in German NICUs.

METHODS

National survey, on-line anonymized questionnaire. German departments stating to run a neurological, neurosurgical or interdisciplinary neurological/neurosurgical intensive care unit were identified by a web-based search of all German hospitals and contacted via email.

RESULTS

Responses from 78 German NICUs were obtained. Of 19 proposed clinical/laboratory/radiological scores only 5 were used regularly by >60 %. Bedside neuromonitoring (NM) predominantly consisted of transcranial Doppler sonography (94 %), electroencephalography (92 %) and measurement of intracranial pressure (ICP) (90 %), and was installed if patients had or were threatened by elevated ICP (86 %), had specific diseases like subarachnoid hemorrhage (51 %) or were comatose (35 %). Although mean trigger values for interventions complied with guidelines or wide-spread customs, individual trigger values varied widely, e.g., for hyperglycemia (maximum blood glucose between 120 and 250 mg/dl) or for anemia (minimum hemoglobin values between 5 and 10 g/dl).

CONCLUSIONS

Although apparently aiming for standardization in neurocritical care, German NICUs show substantial differences in NM and monitoring-associated interventions. In terms of scoring and monitoring methods, German NICUs seem to be quite conservative. These survey results suggest a need of prospective and randomized interventional trials in neurocritical care to help define standards and target values.

Insulin infusion therapy in critical care patients: regular insulin vs short-acting insulin. A prospective, crossover, randomized, multicenter blind study

INTRODUCTION

The aim of this multicenter, prospective, randomized, crossover trial is to compare, in critical care patients receiving insulin infusion therapy (IIT), the pharmacodynamic of Humulin insulin (Hlin), currently used as "standard of care," and Humalog insulin (Hlog), a shorter acting insulin formulation. This was measured as extent and duration of the carryover effect of insulin treatment, with the latter calculated as ratio between blood glucose concentration (BGC) reduction during and after IIT.

MATERIALS AND METHODS

Twenty-eight patients treated in an intensive care unit and receiving full nutritional support were randomly assigned to Hlin or Hlog as first treatment. Insulin was infused at a constant rate in patients presenting with BGC greater than or equal to 180 mg/dL (0.04 U/kg per hour) and was discontinued when BGC was less than or equal to 140 mg/dL (therapeutic BGC drop). Further reductions in BGC after discontinuation of insulin infusion were recorded (postinfusional BGC drop). During the study period, whole blood BGC was measured every 30 minutes. A minimal 6-hour washout interval was maintained between treatments with the 2 types of insulin. The primary end point was the extent (calculated as ratio between the therapeutic BGC drop and the postinfusional BGC drop) and duration of the carryover effect.

RESULTS

Treatment with Hlog, as compared with Hlin, was associated with a less profound carryover effect as well as a briefer duration of carryover (median, 0.40 vs 0.62; P < .001; median, 1 vs 1.5 hours; P < .001).

CONCLUSIONS

The use of constant Hlog infusion for IIT, when compared with Hlin at the same dose, is associated with a less profound carryover effect on BGC after discontinuation of IIT, a briefer duration of carryover, a faster BGC drop during infusion, and a quicker BGC rise after discontinuation. These characteristics suggest that Hlog IIT may be preferable for use in critically ill patients.

Tracking and sustaining improvement initiatives: leveraging quality dashboards to lead change in a neurosurgical department

Increasingly, hospitals and physicians are becoming acquainted with business intelligence strategies and tools to improve quality of care. In 2007, the University of California Los Angeles (UCLA) Department of Neurosurgery created a quality dashboard to help manage process measures and outcomes and ultimately to enhance clinical performance and patient care. At that time, the dashboard was in a platform that required data to be entered manually. It was then reviewed monthly to allow the department to make informed decisions. In 2009, the department leadership worked with the UCLA Medical Center to align mutual quality-improvement priorities. The content of the dashboard was redesigned to include 3 areas of priorities: quality and safety, patient satisfaction, and efficiency and use. Throughout time, the neurosurgery quality dashboard has been recognized for its clarity and its success in helping management direct improvement strategies and monitor impact. We describe the creation and design of the neurosurgery quality dashboard at UCLA, summarize the evolution of its assembly process, and illustrate how it can be used as a powerful tool of improvement and change. The potential challenges and future directions of this business intelligence tool are also discussed.