Near patient blood ketone measurements and their utility in predicting diabetic ketoacidosis

Ketone production and excretion even during mild hyperglycemia and the impact of sodium-glucose co-transporter inhibition in type 1 diabetes

AIMS

We aimed to determine if ketone production and excretion are increased even at mild fasting hyperglycemia in type 1 diabetes (T1D) and if these are modified by ketoacidosis risk factors, including sodium-glucose co-transporter inhibition (SGLTi) and female sex.

METHODS

In secondary analysis of an 8-week single-arm open-label trial of empagliflozin (NCT01392560) we evaluated ketone concentrations during extended fasting and clamped euglycemia (4-6 mmol/L) and mild hyperglycemia (9-11 mmol/L) prior to and after treatment. Plasma and urine beta-hydroxybutyrate (BHB) concentrations and fractional excretion were analyzed by metabolomic analysis.

RESULTS

Forty participants (50 % female), aged 24 ± 5 years, HbA1c 8.0 ± 0.9 % (64 ± 0.08 mmol/mol) with T1D duration of 17.5 ± 7 years, were studied. Increased BHB production even during mild hyperglycemia (median urine 6.3[3.5-13.6] vs. 3.5[2.2-7.0] µmol/mmol creatinine during euglycemia, p < 0.001) was compensated by increased fractional excretion (0.9 % [0.3-1.6] vs. 0.4 % [0.2-0.9], p < 0.001). SGLTi increased production and attenuated the increased BHB fractional excretion (decreased to 0.3 % during mild hyperglycemia, p < 0.001), resulting in higher plasma concentrations (increased to 0.21 [0.05-0.40] mmol/L, p < 0.001), particularly in females (interaction p < 0.001).

CONCLUSIONS

Even mild hyperglycemia is associated with greater ketone production, compensated by urinary excretion, in T1D. However, SGLTi exaggerates production and partially reduces compensatory excretion, particularly in women.

Clinical characteristics and severity of diabetic ketoacidosis: A cross-sectional study from a tertiary hospital in Ghana

OBJECTIVES

Diabetic ketoacidosis (DKA) is a common, severe and often fatal complication of diabetes. This study aimed to investigate the clinical characteristics and precipitants of DKA, as well as factors associated with DKA severity in Ghanaian patients.

METHODS

Cross-sectional study of the medical records of all 70 adult patients >18 years managed for DKA in the adult emergency room of Korle-Bu Teaching Hospital in Ghana from March 2019 to July 2019. DKA diagnosis was based on hyperglycaemia >11.0 mmol/L, ketonuria (more than 2+) plus acidaemia of (pH < 7.3) or bicarbonate (HCO3 - ) <15.0 mmol/L. However, when serum bicarbonate and pH were not available, clinical signs of acidosis, for example, Kussmaul breathing aided in the diagnosis. DKA severity was assessed based on the Joint British Diabetes Societies (JBDS) guidelines of factors suggestive of severe DKA. Multivariable logistic regression was used to determine the factors associated with DKA severity. Odds ratio and 95% confidence interval for factors associated with DKA severity were determined.

RESULTS

The mean (±standard deviation) age, diabetes duration and blood sugar at admission were 44.06 (±16.23) years, 7.19 (±6.04) years and 26.37 (±6.70) mmol/L, respectively. Females comprised 51.4% of the study population. The most common presenting symptoms were generalised weakness (30.0%) and fever (14.3%). The major precipitants were infection (70.0%) and non-compliance (22.9%). Overall, 71.4% of participants had features suggestive of severe DKA. In a multivariable regression model, Type 2 diabetes was associated with over fourfold decreased odds of severe DKA (OR 0.23, 95% CI [0.07-0.76], p = 0.016). Patient education on prevention of DKA was documented for only 18.6% of patients before being discharged.

CONCLUSION

In this study, more than 70% of the study participants had features suggestive of severe DKA, with infection being the most common precipitant of DKA. 51.4% of patients had Type 2 diabetes which was associated with a statistically lower risk of severe DKA. Female sex tended to be positively associated with DKA severity. In a setting where the venous/arterial pH and bicarbonate levels may be inaccessible and/or unaffordable, using clinical features as found in the JBDS guidelines may help categorise patients and escalate care when needed. Indeed it may be useful to validate the use of the JBDS criteria for use in such settings.

Potential Clinical Applications for Continuous Ketone Monitoring in the Hospitalized Patient with Diabetes

PURPOSE OF REVIEW

In this review, the authors discuss potential clinical applications for continuous ketone monitoring (CKM) in a broad continuum of clinical settings from pre-hospital care and the emergency department to acute inpatient management and post-discharge follow-up.

RECENT FINDINGS

Though in its early stages, the concept of a novel continuous ketone sensing technology exerts great potential for use in the detection and hospital management of DKA, namely to overcome diagnostic barriers associated with ketoacidosis in patients with diabetes and obtain real-time BOHB levels, which may be useful in understanding both patients' response to treatment and DKA trajectory. Peri- and intra-operative use of CKM technology can potentially be applied in a number of urgent and elective surgical procedures frequently underwent by patients with diabetes and in the observation of patients during peri-operative fasting. In transitional care management, CKM technology could potentially facilitate patients' safe transition through levels of care, following hospital discharge from a DKA episode. This evaluation of the literature presents the potential advantages of adopting CKM and integrating this technology into the care algorithm of patients at risk for ketoacidosis.

Evaluation of the point-of-care devices KetoSureTM and StatStrip Express® blood ketone tests using β-hydroxybutyrate spiked samples

Measurement of β-hydroxybutyrate (BHB) in blood is used clinically as a measure of ketosis when diabetic ketoacidosis is expected. With the introduction of point-of-care testing (POCT) for blood-BHB, nonproductive time is reduced to a minimum in a potential critical situation; however, studies have observed inferior quality of POCT-BHB. Recently, the POCT device KetoSure (Roche) has been introduced to the clinic. In this study, we evaluated the imprecision and linearity of KetoSure and compared this to the established StatStrip Express (Nova Biomedical) based on spiked full blood samples. We found comparable imprecision for KetoSure and StatStrip Express. However, linearity was only observed in the lower part of the measuring range for both devices. In a method comparison, higher values of BHB were measured by KetoSure than by an enzymatic endpoint spectrophotometric reference method (mean bias: 21% (95% confidence interval (CI): 4%-37%)). Conversely, StatStrip Express returned lower values of BHB (mean bias: -16% (95% CI: -38%-7%), while the widely applied POCT device FreeStyle Precision Neo (Abbott) returned values equivalent with the reference method (mean bias: 5% (95% CI: -14%-24%). In samples with concentrations of BHB above the measuring range, the POCT devices could be provoked to return falsely low results. In conclusion, the quality of KetoSure is in line with other established POCT devices; however, the KetoSure measures higher concentrations than other POCT devices. As, linearity only was observed in the lower part of the measuring range and as falsely low measures could be provoked, we advise users to interpret results with precaution.

Comparisons of biochemical parameters and diabetic ketoacidosis severity in adult patients with type 1 and type 2 diabetes

OBJECTIVE

The aim of this study was to determine the differences in biochemical parameters and diabetic ketoacidosis (DKA) severity in adult patients with type 1 and type 2 diabetes and utilization of serum BHB as a biomarker for DKA resolution was also evaluated.

MATERIALS AND METHODS

This prospective observational study of type 1 or type 2 diabetes mellitus who were diagnosed with DKA between 01 October 2018 and 30 September 2020. The correlations between serum BHB, measured by the Ranbut assay, and pH, bicarbonate, and anion gap were examined.

RESULTS

A total of 99 diabetes patients were diagnosed with DKA (mean age 39.4 years, 63.4% female, 53.6% T2DM). while infection was the most common precipitating factor in T2DM (43.4%), non-compliance with treatment was the most common precipitating factor in T1DM (43.5%). T1DM patients had more severe DKA more hypokalemia during treatment. However, there was no significant difference in mortality between type1 and type2 diabetes. The initial laboratories evaluation of patients did not significant differ between type1 and type2 diabetes. Serum BHB during treatment of DKA was significantly correlated with changes in serum bicarbonate (r = - 0.64), serum anion gap (r = 0.84), and venous pH (r = - 0.6). The serum BHB levels corresponding to HCO₃ levels for DKA severity were 4.5, 5.7, and 5.9 mmol/L in mild, moderate, and severe DKA, respectively. The serum BHB level of < 1 mmol/L had 73.7% sensitivity and 100% specificity to predict DKA resolution. Median time to resolution of DKA was 12 h with an optimized BHB cut-off value of < 1 mmol/L. There were no significant difference in time to resolution of DKA in the patients with type 1 and type 2 diabetes.

CONCLUSIONS

There are no differences in DKA-related biochemical parameters between type 1 and type 2 diabetes patients. The present findings suggest that DKA should be assessed and treated similarly, regardless of its occurrence in type 1 or type 2 diabetes patients.

Smartphone-Powered Electrochemical Dongle for Point-of-Care Monitoring of Blood β-Ketone

A smartphone-powered medical dongle as a miniaturized electrochemical analyzer associated with an enzymatic β-hydroxybutyrate test strip for accurate characterization of blood ketone in peripheral whole blood at the point-of-care, which is capable of providing critical guidance for the evaluation and treatment of diabetic ketoacidosis (DK) and diabetic ketosis acid (DKA), is reported. The measured results of blood ketone by the medical dongle were compared with the clinical results from a bulky biochemical analyzer, and the analysis showed good agreement. The proposed medical smartphone-powered dongle was demonstrated to be a very promising platform as a miniaturized electrochemical analyzer for point-of-care monitoring of the critical biochemical parameters such as blood ketone and a good solution for mobile health management.

Blood Ketones: Measurement, Interpretation, Limitations, and Utility in the Management of Diabetic Ketoacidosis

Diabetic ketoacidosis (DKA) remains a common medical emergency. Over the last few years, new national guidelines have changed the focus in managing the condition from being glucose-centered to ketone-centered. With the advent of advancing technology and the increasing use of hand-held, point-of-care ketone meters, greater emphasis is placed on making treatment decisions based on these readings. Furthermore, recent warnings about euglycemic DKA occurring in people with diabetes using sodium-glucose co-transporter 2 (SGLT-2) inhibitors urge clinicians to inform their patients of this condition and possible testing options. This review describes the reasons for a change in treating DKA, and outlines the benefits and limitations of using ketone readings, in particular highlighting the difference between urine and capillary readings.

Utility of ketone measurement in the prevention, diagnosis and management of diabetic ketoacidosis

Ketone measurement is advocated for the diagnosis of diabetic ketoacidosis and assessment of its severity. Assessing the evidence base for ketone measurement in clinical practice is challenging because multiple methods are available but there is a lack of consensus about which is preferable. Evaluating the utility of ketone measurement is additionally problematic because of variability in the biochemical definition of ketoacidosis internationally and in the proposed thresholds for ketone measures. This has led to conflicting guidance from expert bodies on how ketone measurement should be used in the management of ketoacidosis. The development of point-of-care devices that can reliably measure the capillary blood ketone β-hydroxybutyrate (BOHB) has widened the spectrum of applications of ketone measurement, but whether the evidence base supporting these applications is robust enough to warrant their incorporation into routine clinical practice remains unclear. The imprecision of capillary blood ketone measures at higher values, the lack of availability of routine laboratory-based assays for BOHB and the continued cost-effectiveness of urine ketone assessment prompt further discussion on the role of capillary blood ketone assessment in ketoacidosis. In the present article, we review the various existing methods of ketone measurement, the precision of capillary blood ketone as compared with other measures, its diagnostic accuracy in predicting ketoacidosis and other clinical applications including prevention, assessment of severity and resolution of ketoacidosis.

Accuracy of capillary blood 3-β-hydroxybutyrate determination for the detection and treatment of canine diabetic ketoacidosis

In human medicine, diagnosis of diabetic ketoacidosis (DKA) is usually based on measurement of capillary 3-β-hydroxybutyrate (3-HB) with a hand held ketone sensor. This study was conducted to determine if measurement of capillary 3-HB could be useful for the diagnosis and monitoring of canine DKA. Fifteen dogs with diabetic ketosis and 10 with DKA were evaluated. Paired measurements of 3-HB of capillary and venous blood samples were analysed by the electrochemical sensor and reference method. Use of capillary 3-HB measurement during DKA management was then evaluated through simultaneous measurements of capillary 3-HB, urinary AcAc and venous blood gas analysis. Good agreement between capillary and venous 3-HB measurement was detected by the electrochemical sensor and reference method. Monitoring treatment of DKA revealed a significant correlation between capillary 3-HB and acidosis markers, while no significant correlation was observed between AcAc and acidosis markers. A cut-off value of capillary blood 3-HB >3.8 mmol/L for diagnosis of DKA resulted in 70% and 92% sensitivity and specificity. The electrochemical sensor accurately measures 3-HB concentration in both capillary and venous blood samples, is accurate in diagnosing canine DKA, and appears to reflect the patient's metabolic status during DKA treatment.

Management of raised glucose, a clinical decision tool to reduce length of stay of patients with hyperglycaemia

OBJECTIVE

To assess whether the introduction of a management of raised glucose clinical decision tool could improve assessment of patients with hyperglycaemia by non-specialist physicians, leading to early discharge and improved quality of inpatient care.

METHODS

Participants were adults aged 18 years or over presenting to the Medical Assessment Unit with a capillary blood glucose level > 11.1 mmol/l. Phase 1 of the study (phase 1) evaluated current clinical practice and potential impact of the clinical decision tool. Phase 2 evaluated the effectiveness of the management of raised glucose tool in clinical practice. Primary outcome measures were inpatient length of stay and same-calendar-day discharges. Secondary outcome measures were diabetes specialist input, patient assessment, intravenous insulin infusion use and patient satisfaction.

RESULTS

Implementation of the management of raised glucose clinical decision tool allowed safe, same-calendar-day discharges of 40% of patients with hyperglycaemia as their primary reason for attendance. Median length of stay was lower in the phase 1 than in phase 2 (1.0 vs. 3.5 days, P < 0.01). Early discharge did not result in an increase in readmissions. There was improvement in hyperglycaemia assessment for all patients (P < 0.01), a reduction in the use of intravenous insulin infusions (P < 0.01) and high level of patient satisfaction.

CONCLUSION

The management of raised glucose clinical decision tool resulted in a significant increase in the number of same-calendar-day discharges and reduction in hospital length of stay without adverse impact on readmission rates. Additionally, the tool was associated with improvements in inpatient diabetes care and patient satisfaction.

The role of point-of-care β-hydroxybutyrate testing in the diagnosis of diabetic ketoacidosis: a review

The number of patients with diabetes and diabetes-related complications is increasing. Rapid and accurate diagnosis is key to efficiently providing the appropriate level of care for patients with diabetes. When faced with a hyperglycemic patient (ie, blood glucose level > 250 mg/dL), the prevailing attitude among health care providers is to "think worst first," and common clinical practice is to perform an evaluation for diabetic ketoacidosis (DKA). Traditionally, diagnosing DKA in accordance with the American Diabetes Association guidelines requires performing ≥ 2 (possibly 3) tests to obtain measurements for blood glucose, serum bicarbonate, serum pH, and serum anion gap levels, as well as measurements of either urine or serum ketone bodies. Recently, commercial point-of-care β-hydroxybutyrate measurement devices have become readily accessible and less expensive. These devices offer the potential to simplify clinicians' diagnostic approach to hyperglycemic patients. In this evidence-based literature review, we describe the use of point-of-care β-hydroxybutyrate testing for diagnosing DKA, and discuss its limitations in determining DKA severity.

Measurement of β-hydroxybutyrate in cats with nonketotic diabetes mellitus, diabetic ketosis, and diabetic ketoacidosis

Diabetic ketoacidosis (DKA) is a life-threatening complication of diabetes mellitus (DM). The standard method of detection of ketone bodies is the dipstick method, which detects semiquantitatively acetoacetate, but not β-hydroxybutyrate (β-HB). The objectives of the current study were to assess the diagnostic utility of β-HB to diagnose diabetic ketosis (DK) and DKA in cats and to establish a cut-off value for the diagnosis of DKA. Sixty-two cats were included in the study. Eleven cats were healthy (group 1); in the remainder of cats (51), a diagnosis of DM was based on hyperglycemia, glucosuria, and increased fructosamine concentrations. Nineteen of 51 cats suffered from nonketotic diabetes mellitus (group 2). In 11 cats, plasma ketone bodies were detected with the dipstick method (diabetic ketosis, group 3). In 21 cats, plasma ketone bodies and metabolic acidosis were present (DKA, group 4). Plasma β-HB was measured in all cats by an enzymatic method (spectrophotometry). A cut-off value for the diagnosis of DKA was calculated based on the receiver operating characteristic curve. In healthy cats, the β-HB concentration ranged from 0 to 0.1 mmol/l; in cats of group 2, from 0 to 0.9 mmol/l (median: 0.1 mmol/l); in cats of group 3, from 0.6 to 6.8 mmol/l (median: 1.7 mmol/l); and in cats of group 4, from 3.8 to 12.2 mmol/l (median: 7.9 mmol/l). A cut-off value of 2.4 mmol/l revealed 100% sensitivity and 87% specificity to diagnose DKA. Beta-hydroxybutyrate is a useful parameter for the diagnosis of diabetic ketosis and DKA in cats.

Diagnostic accuracy of point-of-care testing for diabetic ketoacidosis at emergency-department triage: {beta}-hydroxybutyrate versus the urine dipstick

OBJECTIVE

In the emergency department, hyperglycemic patients are screened for diabetic ketoacidosis (DKA) via a urine dipstick. In this prospective study, we compared the test characteristics of point-of-care β-hydroxybutyrate (β-OHB) analysis with the urine dipstick.

RESEARCH DESIGN AND METHODS

Emergency-department patients with blood glucose ≥250 mg/dL had urine dipstick, chemistry panel, venous blood gas, and capillary β-OHB measurements. DKA was diagnosed according to American Diabetes Association criteria.

RESULTS

Of 516 hyperglycemic subjects, 54 had DKA. The urine dipstick had a sensitivity of 98.1% (95% CI 90.1-100), a specificity of 35.1% (30.7-39.6), a positive predictive value of 15% (11.5-19.2), and a negative predictive value of 99.4% (96.6-100) for DKA. Using the manufacturer-suggested cutoff of >1.5 mmol/L, β-OHB had a sensitivity of 98.1% (90.1-100), a specificity of 78.6% (74.5-82.2), a positive predictive value of 34.9% (27.3-43), and a negative predictive value of 99.7% (98.5-100) for DKA.

CONCLUSIONS

Point-of-care β-OHB and the urine dipstick are equally sensitive for detecting DKA (98.1%). However, β-OHB is more specific (78.6 vs. 35.1%), offering the potential to significantly reduce unnecessary DKA work-ups among hyperglycemic patients in the emergency department.

Accuracy of the Precision® point-of-care ketone test examined by liquid chromatography tandem-mass spectrometry (LC-MS/MS) in the same fingerstick sample

BACKGROUND

The Precision(®) (Abbott Diabetes Care) point-of-care biosensor test strips are widely used by patients with diabetes and clinical laboratories for measurement of plasma β-hydroxybutyrate (β-HB) concentrations in capillary blood samples obtained by fingerstick. In the literature, this procedure has been validated only against the enzymatic determination of β-HB in venous plasma, i.e., the method to which the Precision(®) has been calibrated.

METHODS

In this study, the Precision(®) Xceed was compared to a methodologically different and superior procedure: determination of β-HB by liquid chromatography tandem-mass spectrometry (LC-MS/MS) in capillary blood spots. Blood spots were obtained from the same fingerstick sample from out of which Precision(®) measurements were performed. Linearity was tested by adding varying amounts of standard to an EDTA venous whole blood matrix.

RESULTS

The Precision(®) was in good agreement with LC-MS/MS within the measuring range of 0.0-6.0 mmol/L (Passing and Bablok regression: slope=1.20 and no significant intercept, R=0.97, n=59). Surprisingly, the Precision(®) showed non-linearity and full saturation at concentrations above 6.0 mmol/L, which were confirmed by a standard addition experiment. Results obtained at the saturation level varied between 3.0 and 6.5 mmol/L.

CONCLUSIONS

The Precision(®) β-HB test strips demonstrate good comparison with LC-MS/MS. Inter-individual variation around the saturation level, however, is large. Therefore, we advise reporting readings above 3.0 as >3.0 mmol/L. The test is valid for use in the clinically relevant range of 0.0-3.0 mmol/L.

The performance of a glucose-ketone meter in the diagnosis of diabetic ketoacidosis in patients with type 2 diabetes in the emergency room

BACKGROUND

Diabetic ketoacidosis (DKA) is a serious metabolic complication. One of its precipitating causes is insulin omission. DKA requires early diagnosis and strict glucose control, which increases the use of glucose meters in the Emergency Room (ER). We aimed to determine the performance of a glucose-ketone meter in the diagnosis of DKA.

METHODS

From 450 type 2 diabetes mellitus insulin-treated patients attending the ER with a capillary glucose level >13.9 mmol/L, 50 patients (26 men and 24 women, mean age 60.2 +/- 8.2 years) had DKA. Capillary glucose and beta-hydroxybutyrate (beta-OHB) were measured with the Precision-Xtra device (Abbott Laboratories, Abingdon, UK). Serum glucose and biochemical parameters were measured on an automatic analyzer; serum beta-OHB was determined using an enzymatic end-point spectrophotometric method. Urine ketones were determined using a semiquantitative assay (Ketodiastix, Bayer Diagnostics, Stoke Poges, Slough, UK).

RESULTS

Serum and capillary beta-OHB values were highly correlated (r = 0.99, P < 0.001), and the mean difference between them was 0.49 mmol/L (95% confidence interval [CI], 0.35-0.95 mmol/L; P = 0.81). Similarly, serum and capillary glucose values were significantly correlated (r = 0.86, P < 0.001), and the mean difference between them was 0.43 mmol/L (95% CI, 0.82-0.93 mmol/L; P = 0.71). Patients with DKA were inadequately treated with insulin and missed clinic appointments: 80% of patients with DKA compared to 20% of patients without DKA. In all cases, DKA was attributed to insulin omission. Capillary ketonemia (beta-OHB >3.0 mmol/L) had the highest performance (sensitivity 99.87%, specificity 92.89%, positive predictive value 92.89%) for the diagnosis of DKA compared with serum ketonemia (sensitivity 90.45%, specificity 88.65%, positive predictive value 87.76%) or ketonuria (sensitivity 89.89%, specificity 52.73%, positive predictive value 41.87%).

CONCLUSIONS

Implementation of measures such as home glucose and ketone monitoring can possibly decrease the number of hospital admissions due to DKA.

Diabetic emergencies in small animals

Diabetic ketoacidosis and hyperglycemic hyperosmolar syndrome are two serious and potentially life-threatening complications of diabetes mellitus. Understanding pathophysiology is crucial to the proper management of veterinary patients with these disorders. This article reviews the biochemical alterations contributing to these conditions, and discusses traditional and controversial management strategies.

Evaluation of a portable meter to measure ketonemia and comparison with ketonuria for the diagnosis of canine diabetic ketoacidosis

BACKGROUND

The diagnosis of canine diabetic ketoacidosis (DKA) usually is based on measurement of urinary acetoacetate (ketonuria). In humans, this test is less sensitive and specific than blood 3-beta-hydroxybutyrate (ketonemia) evaluation.

HYPOTHESIS

Ketonemia measurement using a portable meter is more accurate than ketonuria determination with a dipstick to diagnose canine DKA.

ANIMALS

Seventy-two client-owned diabetic dogs with ketonemia, ketonuria, or both.

METHODS

Prospective observational study. Based on blood bicarbonate concentration and anion gap, dogs were divided into 2 groups: patients with DKA (n= 25); patients with diabetic ketosis (n= 47). Sensitivity, specificity, and positive and negative likelihood ratio (LR) at different cut-off points were determined for both ketonemia and ketonuria. Receiver operating characteristic (ROC) analysis was used to assess the accuracy of each diagnostic test to diagnose DKA.

RESULTS

With regard to ketonemia, cut-off values of 2.3 and 4.3 mmol/L revealed 100% sensitivity and 100% specificity, respectively, whereas cut-off values of 2.8 and 3.5 mmol/L showed a -LR of 0.05 and a + LR of 13.16, respectively. With regard to ketonuria, a cut-off value of 1+ revealed 92% sensitivity, 40% specificity, and -LR of 0.20, whereas a cut-off value of 3+ revealed 44% sensitivity, 94% specificity, and +LR of 6.89. The areas under the ROC curves for the ketonemia and ketonuria tests were significantly different (0.97 and 0.81, respectively, P= .003).

CONCLUSIONS AND CLINICAL IMPORTANCE

Measurement of ketonemia is accurate and more effective than measurement of ketonuria to diagnose canine DKA.

Bedside detection of urine beta-hydroxybutyrate in diagnosing metabolic acidosis

OBJECTIVES

While critically important, the rapid identification of the etiology of metabolic acidosis (MA) may be labor-intensive and time-consuming. Alcoholic, starvation, and severe diabetic ketoacidosis (AKA, SKA, and DKA, respectively) may produce beta-hydroxybutyrate (BOHB) in marked excess of acetone (ACET) and acetoacetate (AcAc). Unfortunately, current urine dipstick technology poorly detects ACET and cannot measure BOHB. The inability to detect BOHB might delay therapy for ketoacidoses or provoke unnecessary evaluation or empiric treatment of other causes of MA, such as toxic alcohol poisoning. The authors tested the previous assertion that commonly available hydrogen peroxide (H(2)O(2)) would improve BOHB detection. The effectiveness of alkalinization and use of a silver nitrate (AgNO(3)) catalyst was also assessed.

METHODS

Control and urine test specimens containing from 0.5 to 800 mmol/L ACET, AcAc, and BOHB were prepared. Urine specimens were oxidized with H(2)O(2) (3%) 1:9 (H(2)O(2):urine), alkalinized with potassium hydroxide (KOH; 10%), exposed to AgNO(3) sticks, or altered with a combination of these methods in a random fashion. Three emergency physicians (EPs) blinded to the preparation technique evaluated urine dipsticks (Multistix, Bayer Corp.) placed in the specimens for "ketones."

RESULTS

Multistix detected AcAc appropriately; ACET was detected only at high concentrations of >or=600 mmol/L. Multistix failed to measure BOHB at all concentrations tested. H(2)O(2) improved urinary BOHB detection, although not to clinically relevant levels (40 mmol/L). Alkalinization and AgNO(3) sticks did not improve BOHB detection beyond this threshold.

CONCLUSIONS

Addition of H(2)O(2) (3%), alkalinization, or AgNO(3) sticks did not improve clinically meaningful urine BOHB detection. Clinicians should use direct methods to detect BOHB when suspected.

Comparison of capillary blood ketone measurement by electrochemical method and urinary ketone in treatment of diabetic ketosis and ketoacidosis in children

We aimed to compare the recent practical method of capillary beta-hydroxy butyrate (betaOHB) measurement with the widely used urinary ketone measurement in monitoring metabolic status of the patient during treatment of diabetic ketoacidosis (DKA) and diabetic ketosis (DK). Patients with DKA and DK admitted to the hospital were followed with simultaneous measurements of capillary betaOHB by electrochemical method (Medisense Optium, Abbott), and urinary ketone by semi-quantitative method. Blood gases were measured in 2-4 h intervals. Fourteen patients with DKA/DK (7 males and 7 females, age: 9.2 +/- 4.2 years) were included with 50 simultaneous measurements of capillary and urinary ketone. No correlation was detected between urinary ketone and blood pH (P = 0.06) and HCO3 (P = 0.79), whereas a significant negative correlation was found between capillary betaOHB and blood pH (r = -0.41, P < 0.05) and HCO3 (r = -0.35, P < 0.05). Capillary betaOHB and urinary ketone levels did not correlate at the beginning and 3.3 +/- 1.4 h after treatment, but did correlate in the third samples taken 7.8 +/- 2.0 h after treatment (r = 0.8, P < 0.05). Capillary betaOHB levels show good correlation with the degree of acidosis (pH and HCO3). Capillary betaOHB measurement is more sensitive than urinary ketone measurement in reflecting the patient's metabolic status and improvement during treatment.

Can we prevent diabetic ketoacidosis in children?

Diabetic ketoacidosis (DKA) is an acute potentially life-threatening complication of diabetes affecting more than 100,000 persons annually in the United States. Although major advances have improved diabetes care, DKA remains the leading cause of hospitalization, morbidity, and death in youth with type 1 diabetes (T1D). As the majority of patients presenting with DKA have established diabetes, it is important to address outpatient educational approaches directed at sick-day management and early identification and treatment of impending DKA. Teaching and reinforcement of sick-day rules involves improved self-care with consistent self-monitoring of blood glucose and ketones, and timely administration of supplemental insulin and fluids. DKA as an initial manifestation of T1D may be less amendable to prevention except with an increased awareness by the lay and medical communities of the symptoms of diabetes and surveillance in high-risk populations potentially identified by family history or genetic susceptibility. New technologies that can detect the blood ketone 3beta-hydroxybutyrate (3beta-OHB) instead of traditional urine ketones appears to provide opportunity for early identification and treatment of impending DKA leading to reduced need for hospitalization and potential cost-savings.

Hydroxybutyrate near-patient testing to evaluate a new end-point for intravenous insulin therapy in the treatment of diabetic ketoacidosis in children

BACKGROUND

The aim of this study was to assess the clinical application of a near-patient testing (NPT) device for capillary blood hydroxybutyrate (HOB) measurement in evaluating a new end-point for intravenous insulin therapy in the treatment of diabetic ketoacidosis (DKA) in children.

METHODS

Children fulfilling the criteria for DKA were treated according to an integrated care pathway (ICP) with fluid replacement and insulin infusion. We measured capillary HOB hourly by NPT (Abbott Optium meter, analytical range 0-6.0 mmol/L), venous blood gases 4 hourly, and venous HOB 4 hourly by laboratory enzymatic method and tested all urine passed for ketones. Two possible ICP end-points were compared: A, pH > 7.3 followed by two successive NPT HOB measurements <1 mmol/L, and B, pH > 7.3 and urine ketone free (our current end-point).

RESULTS

In 35 patient episodes, the ICP was completed (28 to negative ketonuria) without significant variation. Before treatment, median (range) laboratory HOB was 9.5 mmol/L (4.6-15.70 mmol/L), pH 7.18 (6.98-7.38), and standard bicarbonate 11.5 mmol/L (4.3-18.6 mmol/L). ICP end-point A was reached after 17 h (4-39 h), whereas end-point B was not reached until 28 h (14-64 h) after starting treatment. The median lag was 11 h (1-36 h). For 59 paired venous samples (excluding samples with laboratory HOB >6 mmol/L), the relation between NPT (y) and laboratory (x) HOB was y = 0.92x - 0.05, r(2)= 0.94, mean bias -0.25 mmol/L.

CONCLUSIONS

(i) Serial measurement of NPT HOB allows evaluation of a new, simple, earlier end-point for intravenous insulin therapy. (ii) Agreement between NPT and laboratory HOB was clinically acceptable for HOB levels within the meter's analytical range.

Correlation between urine ketones (acetoacetate) and capillary blood ketones (3-beta-hydroxybutyrate) in hyperglycaemic patients

AIMS

To facilitate the transition from urine ketones (acetoacetate) to capillary blood ketones (3-beta-hydroxybutyrate), we studied the correlation between these two tests.

METHODS

Retrospective study of all patients with blood glucose greater than or equal to 2.5 g/l on arrival in the Emergency Department. We studied the correlation between urine ketones (Clinitek 50, Bayer) and capillary blood ketones (Optium, Abbott). We then compared the relative risks (RR) of ketoacidosis and hospitalization associated with each of these tests.

RESULTS

In 33 months, 529 adult patients with both urine and blood testing for ketones were enrolled (ketoacidosis 8%, admission rate 49%). Urine ketones scored as +, ++ and +++ corresponded to median capillary blood ketone levels of 0.5 mmol/l (IQR: 0.1-0.9), 0.7 mmol/l (IQR: 0.2-1.8) and 3 mmol/l (IQR: 1.4-5.2), respectively. RRs of ketoacidosis or hospitalization associated with blood ketones greater than or equal to 3 mmol/l were higher than those associated with +++ urine ketones: 74 (95% confidence interval [CI]: 48-88) and 2.9 (95% CI: 2.5-3) versus 31 (95% CI: 18-45) and 2 (95% CI: 1.7-2.1), respectively.

CONCLUSIONS

In hyperglycaemic patients in the Emergency Department, a good correlation was observed between urine ketones and capillary blood ketones for low values, but a poor correlation was observed for high values. Either test can therefore be used to exclude ketosis, but the capillary blood ketones test is more accurate to confirm ketoacidosis.

Bedside monitoring of blood beta-hydroxybutyrate levels in the management of diabetic ketoacidosis in children

INTRODUCTION

Diabetic ketoacidosis (DKA) affects many children with type 1 diabetes. Insulin treatment of DKA is traditionally guided by changes in the blood glucose levels and blood gases, whereas beta-hydroxybutyrate (beta-OHB)--the main ketoacid causing acidosis--is rarely measured. The purpose of this study was to evaluate if bedside monitoring of blood beta-OHB levels can simplify management of DKA through elimination of superfluous laboratory monitoring.

METHODS

Our emergency department treated 68 children with DKA using a standard protocol with monitoring of venous pH, partial pressure of CO(2) (pCO(2)), bicarbonate, glucose, blood urea nitrogen, and electrolytes (two to 10 time points per patient). Venous beta-OHB levels were measured using the Precision Xtra meter (MediSense/Abbott Diabetes Care, Abbott Park, IL) and, on duplicate batched serum samples, using a reference laboratory method (Cobas Mira Plus; Roche Diagnostics, Indianapolis, IN). Correlations between bedside meter beta-OHB and other parameters were evaluated in a series of general linear models with a time series covariance structure fit using spatial power law.

RESULTS

The bedside meter beta-OHB levels were significantly correlated with pH (r = -0.63; P <0.0001), bicarbonate (r = -0.74; P <0.0001), and pCO(2) (r = -0.55; P <0.0001) at all points of measurement during the treatment (unadjusted Pearson correlations). The pH, bicarbonate, and pCO(2) were entered into separate time series analysis models with treatment duration as a measure of time. The results confirmed that bedside levels of beta-OHB correlated very closely with time-dependent levels of venous pH, bicarbonate, and pCO(2). Good agreement between the two methods of beta-OHB measurement (r = 0.92; P <0.0001) was confirmed using the Bland-Altman plot analysis.

CONCLUSIONS

The Precision Xtra accurately measures blood beta-OHB levels, particularly at lower levels. While the initial measurement of pH and/or bicarbonates is warranted, real-time beta-OHB levels may replace repeat laboratory measurement of these parameters in the management of DKA. Future studies should evaluate safety and cost-effectiveness of such simplified DKA treatment protocol.