Malglycemia in the critical care setting. Part III: Temporal patterns, relative potencies, and hospital mortality.

INTRODUCTION: The relationship between critical care mortality and combined impact of malglycemia remains undefined. METHODS: We assessed the risk-adjusted relationship (n = 4790) between hospital mortality with malglycemia, defined as hypergycemia (hours Glycemic Ratio ≥ 1.1, where GR is quotient of mean ICU blood glucose (BG) and estimated average BG), absolute hypoglycemia (hours BG < 70 mg/dL) and relative hypoglycemia (excursions GR < 0.7 in those with HbA1c ≥ 8%). RESULTS: Each malglycemia was independently associated with mortality - hyperglycemia (OR 1.0020/h, 95%CI 1.0009-1.0031, p = 0.0004), absolute hypoglycemia (OR 1.0616/h, 95%CI 1.0190-1.1061, p = 0.0043), and relative hypoglycemia (OR 1.2813/excursion, 95%CI 1.0704-1.5338, p = 0.0069). Absolute (7.4%) and relative hypoglycemia (6.7%) exposure dominated the first 24 h, decreasing thereafter. While hyperglycemia had lower risk association with mortality, it was persistently present across the length-of-stay (68-76% incidence daily), making it the dominant form of malglycemia. Relative contributions in the first five days from hyperglycemia, absolute hypoglycemia and relative hypoglycemia were 60%, 21% and 19% respectively. CONCLUSIONS: Absolute and relative hypoglycemia occurred largely in the first 24 h. Relative to all hypoglycemia, the associated mortality from the seemingly less potent but consistently more prevalent hyperglycemia steadily accumulated with increasing length-of-stay. This has important implications for interpretation of study results.

Society of Critical Care Medicine Guidelines on Glycemic Control for Critically Ill Children and Adults 2024.

RATIONALE: Maintaining glycemic control of critically ill patients may impact outcomes such as survival, infection, and neuromuscular recovery, but there is equipoise on the target blood levels, monitoring frequency, and methods. OBJECTIVES: The purpose was to update the 2012 Society of Critical Care Medicine and American College of Critical Care Medicine (ACCM) guidelines with a new systematic review of the literature and provide actionable guidance for clinicians. PANEL DESIGN: The total multiprofessional task force of 22, consisting of clinicians and patient/family advocates, and a methodologist applied the processes described in the ACCM guidelines standard operating procedure manual to develop evidence-based recommendations in alignment with the Grading of Recommendations Assessment, Development, and Evaluation Approach (GRADE) methodology. Conflict of interest policies were strictly followed in all phases of the guidelines, including panel selection and voting. METHODS: We conducted a systematic review for each Population, Intervention, Comparator, and Outcomes question related to glycemic management in critically ill children (≥ 42 wk old adjusted gestational age to 18 yr old) and adults, including triggers for initiation of insulin therapy, route of administration, monitoring frequency, role of an explicit decision support tool for protocol maintenance, and methodology for glucose testing. We identified the best available evidence, statistically summarized the evidence, and then assessed the quality of evidence using the GRADE approach. We used the evidence-to-decision framework to formulate recommendations as strong or weak or as a good practice statement. In addition, "In our practice" statements were included when the available evidence was insufficient to support a recommendation, but the panel felt that describing their practice patterns may be appropriate. Additional topics were identified for future research. RESULTS: This guideline is an update of the guidelines for the use of an insulin infusion for the management of hyperglycemia in critically ill patients. It is intended for adult and pediatric practitioners to reassess current practices and direct research into areas with inadequate literature. The panel issued seven statements related to glycemic control in unselected adults (two good practice statements, four conditional recommendations, one research statement) and seven statements for pediatric patients (two good practice statements, one strong recommendation, one conditional recommendation, two "In our practice" statements, and one research statement), with additional detail on specific subset populations where available. CONCLUSIONS: The guidelines panel achieved consensus for adults and children regarding a preference for an insulin infusion for the acute management of hyperglycemia with titration guided by an explicit clinical decision support tool and frequent (≤ 1 hr) monitoring intervals during glycemic instability to minimize hypoglycemia and against targeting intensive glucose levels. These recommendations are intended for consideration within the framework of the patient's existing clinical status. Further research is required to evaluate the role of individualized glycemic targets, continuous glucose monitoring systems, explicit decision support tools, and standardized glycemic control metrics.

Malglycemia in the critical care setting. Part II: Relative and absolute hypoglycemia.

INTRODUCTION: The relationship between critical care mortality and hypoglycemia, both relative (>30% below average preadmission glycemia) and absolute (blood glucose (BG) <70 mg/dL (<10 mmol/L)) requires further definition. METHODS: We assessed the risk-adjusted relationship between hospital mortality with relative hypoglycemia using the Glycemic Ratio (GR), and with absolute hypoglycemia using BG in a retrospective cohort investigation (n = 4790). RESULTS: Relative hypoglycemia excursions below GR 0.7 with a of 24-h non-exposure period between excursions in those with HbA1c ≥ 8% were independently associated with mortality (n = 373, OR 2.49, 95% CI 1.54-4.04, p = 0.0002) but not those with HbA1c < 8% (n = 4417, OR 0.98 95% CI 0.89-1.08, p = 0.70). Hours below GR 0.7 (1.0037, 0.9995-1.0080, 0.0846) or minimum GR (0.0896, 0.0030-2.6600, 0.1632) were not independently associated with outcome. Absolute hypoglycemia occurred across the HbA1c spectrum in a U-shaped pattern. There was no difference in mortality associated with exposure to BG < 70 mg/dL for HbA1c ≥ 6.5% vs <6.5% (29.7% vs 24.3%, p = 0.77). Hours below 70 mg/dL demonstrated strongest association with outcome, while minimum BG, and excursions below 70 mg/dL were also independently associated. CONCLUSIONS: Relative hypoglycemia represented by excursions below GR 0.7 in those with HbA1c ≥ 8% occurred commonly and was independently associated with mortality. Absolute hypoglycemia had similar association with mortality regardless of HbA1c.

Malglycemia in the critical care setting. Part I: Defining hyperglycemia in the critical care setting using the glycemic ratio.

INTRODUCTION: Stress-induced hyperglycemia (SIH) is conventionally represented by Blood Glucose (BG) although recent evidence indicates the Glycemic Ratio (GR, quotient of mean BG and estimated preadmission BG) is a superior prognostic marker. We assessed the association between in-hospital mortality and SIH, using BG and GR in an adult medical-surgical ICU. METHODS: We included patients with hemoglobin A1c (HbA1c) and minimum four BGs in a retrospective cohort investigation (n = 4790). RESULTS: A critical SIH threshold of GR 1.1 was identified. Mortality increased with increasing exposure to GR ≥ 1.1 (r2 = 0.94, p = 0.0007). Duration of exposure to BG ≥ 180 mg/dL demonstrated a less robust association with mortality (r2 = 0.75, p = 0.059). In risk-adjusted analyses, hours GR ≥ 1.1 (OR 1.0014, 95%CI (1.0003-1.0026), p = 0.0161) and hours BG ≥ 180 mg/dL (OR 1.0080, 95%CI (1.0034-1.0126), p = 0.0006) were associated with mortality. In the cohort with no exposure to hypoglycemia however, only hours GR ≥ 1.1 was associated with mortality (OR 1.0027, 95%CI (1.0012-1.0043), p = 0.0007), not BG ≥ 180 mg/dL (OR 1.0031, 95%CI (0.9949-1.0114), p = 0.50) and this relationship remained intact for those who never experienced BG outside the 70-180 mg/dL range (n = 2494). CONCLUSIONS: Clinically significant SIH commenced above GR 1.1. Mortality was associated with hours of exposure to GR ≥ 1.1 which was a superior marker of SIH compared to BG.

Brain Glucose Sensing and the Problem of Relative Hypoglycemia.

"Relative hypoglycemia" is an often-overlooked complication of diabetes characterized by an increase in the glycemic threshold for detecting and responding to hypoglycemia. The clinical relevance of this problem is linked to growing evidence that among patients with critical illness, higher blood glucose in the intensive care unit is associated with higher mortality among patients without diabetes but lower mortality in patients with preexisting diabetes and an elevated prehospitalization HbA1c. Although additional studies are needed, the cardiovascular stress associated with hypoglycemia perception, which can occur at normal or even elevated glucose levels in patients with diabetes, offers a plausible explanation for this difference in outcomes. Little is known, however, regarding how hypoglycemia is normally detected by the brain, much less how relative hypoglycemia develops in patients with diabetes. In this article, we explore the role in hypoglycemia detection played by glucose-responsive sensory neurons supplying peripheral vascular beds and/or circumventricular organs. These observations support a model wherein relative hypoglycemia results from diabetes-associated impairment of this neuronal glucose-sensing process. By raising the glycemic threshold for hypoglycemia perception, this impairment may contribute to the increased mortality risk associated with standard glycemic management of critically ill patients with diabetes.

Case-control Investigation of Previously Undiagnosed Diabetes in the Critically Ill.

Context: The outcome of patients requiring intensive care can be influenced by the presence of previously undiagnosed diabetes (undiagDM). Objective: This work aimed to define the clinical characteristics, glucose control metrics, and outcomes of patients admitted to the intensive care unit (ICU) with undiagDM, and compare these to patients with known DM (DM). Methods: This case-control investigation compared undiagDM (glycated hemoglobin A1c [HbA1c] ≥ 6.5%, no history of diabetes) to patients with DM. Glycemic ratio (GR) was calculated as the quotient of mean ICU blood glucose (BG) and estimated preadmission glycemia, based on HbA1c ([28.7 × HbA1c] - 46.7 mg/dL). GR was analyzed by bands: less than 0.7, 0.7 to less than or equal to 0.9, 0.9 to less than 1.1, and greater than or equal to 1.1. Risk-adjusted mortality was represented by the Observed:Expected mortality ratio (OEMR), calculated as the quotient of observed mortality and mortality predicted by the severity of illness (APACHE IV prediction of mortality). Results: Of 5567 patients 294 (5.3%) were undiagDM. UndiagDM had lower ICU mean BG (P < .0001) and coefficient of variation (P < .0001) but similar rates of hypoglycemia (P = .08). Mortality and risk-adjusted mortality were similar in patients with GR less than 1.1 comparing undiagDM and DM. However, for patients with GR greater than or equal to 1.1, mortality (38.5% vs 10.3% [P = .0072]) and risk-adjusted mortality (OEMR 1.18 vs 0.52 [P < .0001]) were higher in undiagDM than in DM. Conclusion: These data suggest that DM patients may develop tolerance to hyperglycemia that occurs during critical illness, a protective mechanism not observed in undiagDM, for whom hyperglycemia remains strongly associated with higher risk of mortality. These results may shed light on the natural history of diabetes.

The Glycemic Ratio Is Strongly and Independently Associated With Mortality in the Critically Ill.

BACKGROUND: Interventional studies investigating blood glucose (BG) management in intensive care units (ICU) have been inconclusive. New insights are needed. We assessed the ability of a new metric, the Glycemic Ratio (GR), to determine the relationship of ICU glucose control relative to preadmission glycemia and mortality. METHODS: Retrospective cohort investigation (n = 4790) in an adult medical-surgical ICU included patients with minimum four BGs, hemoglobin (Hgb), and hemoglobin A1c (HbA1c). The GR is the quotient of mean ICU BGs (mBG) and estimated preadmission BG, derived from HbA1c. RESULTS: Mortality displayed a J-shaped curve with GR (nadir GR 0.9), independent of background glycemia, consistent for HbA1c <6.5% vs >6.5%, and Hgb >10 g/dL vs <10 g/dL and medical versus surgical. An optimal range of GR 0.80 to 0.99 was associated with decreased mortality compared with GR above and below this range. The mBG displayed a linear relationship with mortality at lower HbA1c but diminished for HbA1c >6.5%, and dependent on preadmission glycemia. In adjusted analysis, GR remained associated with mortality (odds ratio = 2.61, 95% confidence interval = 1.48-4.62, P = .0012), but mBG did not (1.004, 1.000-1.009, .059). A single value on admission was not independently associated with mortality. CONCLUSIONS: The GR provided new insight into malglycemia that was not apparent using mBG, or an admission value. Mortality was associated with acute change from preadmission glycemia (GR). Further assessment of the impact of GR deviations from the nadir in mortality at GR 0.80 to 0.99, as both relative hypo- and hyperglycemia, and as duration of exposure and intensity, may further define the multifaceted nature of malglycemia.

Quantification of stress-induced hyperglycaemia associated with key diagnostic categories using the stress hyperglycaemia ratio.

AIM: Stress-induced hyperglycaemia (SIH) is the acute increase from preadmission glycaemia and is associated with poor outcomes. Early recognition of SIH and subsequent blood glucose (BG) management improves outcomes, but the degree of SIH provoked by distinct diagnostic categories remains unknown. Quantification of SIH is now possible using the stress hyperglycaemia ratio (SHR), which measures the proportional change from preadmission glycaemia, based on haemoglobin A1c (HbA1c ). METHODS: We identified eligible patients for eight medical (n = 892) and eight surgical (n = 347) categories. Maximum BG from the first 24 h of admission for medical, or postoperatively for surgical patients was used to calculate SHR. RESULTS: Analysis of variance indicated differing SHR and BG within both the medical (p < 0.0001 for both) and surgical cohort (p < 0.0001 for both). Diagnostic categories were associated with signature levels of SHR that varied between groups. Medically, SHR was greatest for ST-elevation myocardial infarction (1.22 ± 0.33) and sepsis (1.37 ± 0.43). Surgically, SHR was greatest for colectomy (1.62 ± 0.48) and cardiac surgeries (coronary artery graft 1.56 ± 0.43, aortic valve replacement 1.71 ± 0.33, and mitral valve replacement 1.75 ± 0.34). SHR values remained independent of HbA1c , with no difference for those with HbA1c above or below 6.5% (p > 0.11 for each). BG however was highly dependent on HbA1c , invariably elevated in those with HbA1c  ≥ 6.5% (p < 0.001 for each), and unreliably reflected SIH. CONCLUSION: The acute stress response associated with various medical and surgical categories is associated with signature levels of SIH. Those with higher expected SHR are more likely to benefit from early SIH management, especially major surgery, which induced SIH typically 40% greater than medical cohorts. SHR equally recognised the acute change in BG from baseline across the full HbA1c spectrum while BG did not and poorly reflected SIH.

Relative Hypoglycemia and Lower Hemoglobin A1c-Adjusted Time in Band Are Strongly Associated With Increased Mortality in Critically Ill Patients.

OBJECTIVES: To determine the associations of relative hypoglycemia and hemoglobin A1c-adjusted time in blood glucose (BG) band (HA-TIB) with mortality in critically ill patients. DESIGN: Retrospective cohort investigation. SETTING: University-affiliated adult medical-surgical ICU. PATIENTS: Three thousand six hundred fifty-five patients with at least four BG tests and hemoglobin A1c (HbA1c) level admitted between September 14, 2014, and November 30, 2019. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients were stratified for HbA1c bands of <6.5%; 6.5-7.9%; greater than or equal to 8.0% with optimal affiliated glucose target ranges of 70-140, 140-180, and 180-250 mg/dL, respectively. HA-TIB, a new glycemic metric, defined the HbA1c-adjusted time in band. Relative hypoglycemia was defined as BG 70-110 mg/dL for patients with HbA1c ≥ 8.0%. Further stratification included diabetes status-no diabetes (NO-DM, n = 2,616) and preadmission treatment with or without insulin (DM-INS, n = 352; DM-No-INS, n = 687, respectively). Severity-adjusted mortality was calculated as the observed:expected mortality ratio (O:EMR), using the Acute Physiology and Chronic Health Evaluation IV prediction of mortality. Among NO-DM, mortality and O:EMR, decreased with higher TIB 70-140 mg/dL ( p < 0.0001) and were lowest with TIB 90-100%. O:EMR was lower for HA-TIB greater than or equal to 50% than less than 50% and among all DM-No-INS but for DM-INS only those with HbA1 greater than or equal to 8.0%.Among all patients with hba1c greater than or equal to 8.0% And no bg less than 70 mg/dl, mortality was 18.0% For patients with relative hypoglycemia (bg, 70-110 mg/dl) ( p < 0.0001) And was 0.0%, 12.9%, 13.0%, And 34.8% For patients with 0, 0.1-2.9, 3.0-11.9, And greater than or equal to 12.0 Hours of relative hypoglycemia ( p < 0.0001). CONCLUSIONS: These findings have considerable bearing on interpretation of previous trials of intensive insulin therapy in the critically ill. Moreover, they suggest that BG values in the 70-110 range may be deleterious for patients with HbA1c greater than or equal to 8.0% and that the appropriate target for BG should be individualized to HbA1c levels. These conclusions need to be tested in randomized trials.

Acute and Chronic Glucose Control in Critically Ill Patients With Diabetes: The Impact of Prior Insulin Treatment.

BACKGROUND: Emerging data highlight the interactions of preadmission glycemia, reflected by admission HbA1c levels, glycemic control during critical illness, and mortality. The association of preadmission insulin treatment with outcomes is unknown. METHODS: This observational cohort study includes 5245 patients admitted to the medical-surgical intensive care unit of a university-affiliated teaching hospital. Three groups were analyzed: patients with diabetes with prior insulin treatment (DM-INS, n = 538); patients with diabetes with no prior insulin treatment (DM-No-INS, n = 986); no history of diabetes (NO-DM, n = 3721). Groups were stratified by HbA1c level: <6.5%; 6.5%-7.9% and >8.0%. RESULTS: Among the three strata of HbA1c, mean blood glucose (BG), coefficient of variation (CV), and hypoglycemia increased with increasing HbA1c, and were higher for DM-INS than for DM-No-INS. Among patients with HbA1c < 6.5%, mean BG ≥ 180 mg/dL and CV > 30% were associated with lower severity-adjusted mortality in DM-INS compared to patients with mean BG 80-140 mg/dL and CV < 15%, (P = .0058 and < .0001, respectively), but higher severity-adjusted mortality among DM-No-INS (P = .0001 and < .0001, respectively) and NON-DM (P < .0001 and < .0001, respectively). Among patients with HbA1c ≥ 8.0%, mean BG ≥ 180 mg/dL was associated with lower severity-adjusted mortality for both DM-INS and DM-No-INS than was mean BG 80-140 mg/dL (p < 0.0001 for both comparisons). CONCLUSIONS: Significant differences in mortality were found among patients with diabetes based on insulin treatment and HbA1c at home and post-admission glycemic control. Prospective studies need to confirm an individualized approach to glycemic control in the critically ill.

Fifteen-minute Frequency of Glucose Measurements and the Use of Threshold Alarms: Impact on Mitigating Dysglycemia in Critically Ill Patients.

BACKGROUND: The use of near-continuous blood glucose (BG) monitoring has the potential to improve glycemic control in critically ill patients. The MANAGE IDE trial evaluated the performance of the OptiScanner (OS) 5000 in a multicenter cohort of 200 critically ill patients. METHODS: An Independent Group reviewed the BG run charts of all 200 patients and voted whether unblinded use of the OS, with alarms set at 90 and 130 to 150 mg/dL to alert the clinical team to impending hypoglycemia and hyperglycemia, respectively, would have eliminated episodes of dysglycemia: hypoglycemia, defined as a single BG <70 mg/dL; hyperglycemia, defined as >4 hours of BG >150 mg/dL; severe hyperglycemia, defined as >4 hours of BG >200 mg/dL and increased glucose variability (GV), defined as coefficient of variation (CV) >20%. RESULTS: At least one episode of dysglycemia occurred in 103 (51.5%) of the patients, including 6 (3.0%) with hypoglycemia, 83 (41.5%) with hyperglycemia, 18 (9.0%) with severe hyperglycemia, and 40 (20.0%) with increased GV. Unblinded use of the OS with appropriate alarms would likely have averted 97.1% of the episodes of dysglycemia: hypoglycemia (100.0%), hyperglycemia (96.4%), severe hyperglycemia (100.0%), and increased GV (97.5%). Point accuracy of the OS was very similar to that of the point of care BG monitoring devices used in the trial. CONCLUSION: Unblinded use of the OS would have eliminated nearly every episode of dysglycemia in this cohort of critically ill patients, thereby markedly improving the quality and safety of glucose control.

The Interaction of Acute and Chronic Glycemia on the Relationship of Hyperglycemia, Hypoglycemia, and Glucose Variability to Mortality in the Critically Ill.

OBJECTIVES: To determine the relationship between preadmission glycemia, reflected by hemoglobin A1c level, glucose metrics, and mortality in critically ill patients. DESIGN: Retrospective cohort investigation. SETTING: University affiliated adult medical-surgical ICU. PATIENTS: The investigation included 5,567 critically ill patients with four or more blood glucose tests and hemoglobin A1c level admitted between October 11, 2011 and November 30, 2019. The target blood glucose level was 90-120 mg/dL for patients admitted before September 14, 2014 (n = 1,614) and 80-140 mg/dL or 110-160 mg/dL for patients with hemoglobin A1c less than 7% or greater than or equal to 7% (n = 3,953), respectively, subsequently. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients were stratified by hemoglobin A1c: less than 6.5.(n = 4,406), 6.5-7.9% (n = 711), and greater than or equal to 8.0% (n = 450). Increasing hemoglobin A1c levels were associated with significant increases in mean glycemia, glucose variability, as measured by coefficient of variation, and hypoglycemia (p for trend < 0.0001, < 0.0001, and 0.0010, respectively). Among patients with hemoglobin A1c less than 6.5%, mortality increased as mean glycemia increased; however, among patients with hemoglobin A1c greater than or equal to 8.0%, the opposite relationship was observed (p for trend < 0.0001 and 0.0027, respectively). Increasing glucose variability was independently associated with increasing mortality only among patients with hemoglobin A1c less than 6.5%. Hypoglycemia was independently associated with higher mortality among patients with hemoglobin A1c less than 6.5% and 6.5-7.9% but not among those with hemoglobin A1c greater than or equal to 8.0%. Mean blood glucose 140-180 and greater than or equal to 180 mg/dL were independently associated with higher mortality among patients with hemoglobin A1c less than 6.5% (p < 0.0001 for each). Among patients with hemoglobin A1c greater than or equal to 8.0% treated in the second era, mean blood glucose greater than or equal to 180 mg/dL was independently associated with decreased risk of mortality (p = 0.0358). CONCLUSIONS: Preadmission glycemia, reflected by hemoglobin A1c obtained at the onset of ICU admission, has a significant effect on the relationship of ICU glycemia to mortality. The different responses to increasing mean glycemia support a personalized approach to glucose control practices in the ICU.

Reducing Hypoglycemia in Critical Care Patients Using a Nurse-Driven Root Cause Analysis Process.

BACKGROUND: Successful blood glucose control is associated with improved outcomes of critically ill patients. However, insulin treatment can cause hypoglycemia, an important patient safety concern. The Joint Commission has recommended that all episodes of hypoglycemia be evaluated with a root cause analysis. OBJECTIVE: To reduce episodes of hypoglycemia through the analysis of data related to each episode. METHODS: The interdisciplinary team of the 16-bed critical care unit of a university-affilited teaching hospital developed a process to analyze, in real time, each episode of hypoglycemia (blood glucose level <60 mg/dL), including evaluation of patient risk factors and nursing interventions. The nursing staff integrated the root cause analysis into daily practice. The preimplementation period encompassed 2429 consecutive admissions, and the implementation period encompassed 2608 consecutive admissions. RESULTS: The percentage of patients with hypoglycemia decreased substantially during the implementation period among those without (from 6.15% to 3.78%; P = .001) and with diabetes (from 13.14% to 7.23%; P = .002). Mean blood glucose level decreased during the implementation period among patients without diabetes (P < .001), and did not change significantly among patients with diabetes (P = .23). The coefficient of variation, reflecting glucose variability, decreased during the implementation period among patients without and with diabetes (P < .001 for each). CONCLUSION: The nurse-driven root cause analysis was associated with a substantial reduction in hypoglycemia, with concomitant decreases in mean blood glucose level among patients without diabetes and glucose variability in patients without and with diabetes.

Is it time to abandon glucose control in critically ill adult patients?

PURPOSE OF REVIEW: To summarize the advances in literature that support the best current practices regarding glucose control in the critically ill. RECENT FINDINGS: There are differences between patients with and without diabetes regarding the relationship of glucose metrics during acute illness to mortality. Among patients with diabetes, an assessment of preadmission glycemia, using measurement of Hemoglobin A1c (HgbA1c) informs the choice of glucose targets. For patients without diabetes and for patients with low HgbA1c levels, increasing mean glycemia during critical illness is independently associated with increasing risk of mortality. For patients with poor preadmission glucose control the appropriate blood glucose target has not yet been established. New metrics, including stress hyperglycemia ratio and glycemic gap, have been developed to describe the relationship between acute and chronic glycemia. SUMMARY: A 'personalized' approach to glycemic control in the critically ill, with recognition of preadmission glycemia, is supported by an emerging literature and is suitable for testing in future interventional trials.

Percentage of Time in Range 70 to 139 mg/dL Is Associated With Reduced Mortality Among Critically Ill Patients Receiving IV Insulin Infusion.

BACKGROUND: In addition to hyperglycemia, hypoglycemia, and glycemic variability, reduced time in targeted blood glucose range (TIR) is associated with increased risk of death in critically ill patients. This relation between TIR and mortality may be confounded by diabetic status and antecedent glycemic control. METHODS: This study retrospectively analyzed critically ill patients managed with the same IV insulin protocol at multiple centers. The percentage of TIR between 70 and 139 mg/dL was calculated. Patients with diabetic ketoacidosis, patients who had < 10 blood glucose readings, and patients with repeat admissions were excluded. The highest recorded glycosylated hemoglobin value in the preceding 3 months or up to 1 month following admission were used as a surrogate for the patient's preexisting glucose control. Stratified regression analyses were performed for 30-day mortality, with covariates of age, sex, TIR ≥ 80%, Acute Physiology Score, and Charlson Comorbidity Index. RESULTS: A total of 9,028 patients, 53.2% of whom had diabetes, were studied. Median TIR was 84.1% for nondiabetic patients and 64.5% for patients with diabetes. Mortality was lower in those with TIR > 80% compared with those with TIR ≤ 80% (12.4% vs 19.2%; P < .001). TIR > 80% was independently associated with reduced mortality in nondiabetic patients (OR, 0.52; P < .001), patients with diabetes (OR, 0.69; P = .001), and patients with well-controlled disease (OR, 0.50; P < .001) but not in patients with poorly controlled disease (OR, 0.86; P = .40). CONCLUSIONS: TIR was independently associated with mortality in critically ill patients, particularly those with good antecedent glucose control.