Factors predicting cerebral edema in young children with diabetic ketoacidosis and new onset type I diabetes

Correlation between Neutrophil-to-Lymphocyte Ratio and Cerebral Edema in Children with Severe Diabetic Ketoacidosis

Diabetic ketoacidosis (DKA), a common onset modality of type 1 diabetes mellitus (T1DM), can lead, in rare instances, to the development of cerebral edema, which is the leading cause of mortality in T1DM. Aside from the identification of several demographic and clinical risk factors for cerebral edema, attention has also been drawn to the possible link between systemic inflammation and neuroinflammation. This single-center retrospective study of 98 children with severe DKA aimed to investigate the possible relationship between neutrophil-to-lymphocyte ratio NLR) levels and the presence of cerebral edema. Patients were classified into three groups: alert (n = 28), subclinical cerebral edema (n = 59), and overt cerebral edema (n = 11). Lower blood pH and elevated NLR and blood urea were correlated with the presence of cerebral edema (p < 0.001). After a multivariable risk adjustment for possible confounding factors, such as age, pH, corrected sodium, and BUN, the NLR remained positively associated with cerebral edema (p = 0.045). As such, NLR may be an additional instrument to help practitioners target patients with a higher risk of severe cerebral edema. These patients would benefit from more rigorous neurologic surveillance, enabling the prompt identification of early signs of cerebral edema.

Management of severe inaugural diabetic ketoacidosis in paediatric intensive care: retrospective comparison of two protocols

The best protocol for severe inaugural diabetic ketoacidosis (DKA) in children remains unclear. We compared two protocols by assessing effects during the first 24 h on osmolality, serum sodium, and glucose variations, which are associated with the risk of cerebral oedema, the most dreaded complication of DKA. We also recorded complications. We retrospectively included children aged 28 days to 18 years and admitted for severe DKA to either of two paediatric intensive care units (PICUs) in Paris (France). The two protocols differed regarding hydration volume, glucose intake, and sodium intake. From 17 June 2010 to 17 June 2015, 93 patients were included, 29 at one PICU, and 64 at the other. We compared severe glycaemic drops (> 5.5 mmol/L/h), mean glycaemia variations, serum sodium, serum osmolality, and the occurrence of cerebral oedema (CE) during the first 24 h after PICU admission. Severe glycaemic drops occurred in 70% of patients, with no between-group difference. Blood glucose, serum sodium, and serum osmolality variations were comparable. Seven (7.5%) patients were treated for suspected CE, (4 [10.3%)] and 3 [6.3%]) in each PICU; none had major residual impairments.

CONCLUSION

 The two paediatric DKA-management protocols differing in terms of fluid-volume, glucose, and sodium intakes had comparable effects on clinical and laboratory-test changes within 24 h. Major drops in glycaemia and osmolality were common with both protocols. No patients had residual neurological impairments.

WHAT IS KNOWN

• Cerebral oedema is the most severe complication of diabteic ketoacidosis in children.The risk of cerebral oedema is dependant on both patient related and treatment-related factors. • The optimal protocol for managing severe inaugural diabetic ketoacidosis in children remains unclear, and few studies have targeted this specific population.

WHAT IS NEW

• Two management protocols that complied with ISPAD guidelines but differed regarding the amounts of fluids, glucose, and sodium administered produced similar outcomes in children with severe inaugural diabetic ketoacidosis. • Cerebral oedema was rare with both protocols and caused no lasting impairments.

Brain injury in children with diabetic ketoacidosis: Review of the literature and a proposed pathophysiologic pathway for the development of cerebral edema

Cerebral edema (CE) is a potentially devastating complication of diabetic ketoacidosis (DKA) that almost exclusively occurs in children. Since its first description in 1936, numerous risk factors have been identified; however, there continues to be uncertainty concerning the mechanisms that lead to its development. Currently, the most widely accepted hypothesis posits that CE occurs as a result of ischemia-reperfusion injury, with inflammation and impaired cerebrovascular autoregulation contributing to its pathogenesis. The role of specific aspects of DKA treatment in the development of CE continues to be controversial. This review critically examines the literature on the pathophysiology of CE and attempts to categorize the findings by types of brain injury that contribute to its development: cytotoxic, vasogenic, and osmotic. Utilizing this scheme, we propose a multifactorial pathway for the development of CE in patients with DKA.

The Corrected Serum Sodium Concentration in Hyperglycemic Crises: Computation and Clinical Applications

In hyperglycemia, hypertonicity results from solute (glucose) gain and loss of water in excess of sodium plus potassium through osmotic diuresis. Patients with stage 5 chronic kidney disease (CKD) and hyperglycemia have minimal or no osmotic diuresis; patients with preserved renal function and diabetic ketoacidosis (DKA) or hyperosmolar hyperglycemic state (HHS) have often large osmotic diuresis. Hypertonicity from glucose gain is reversed with normalization of serum glucose ([Glu]); hypertonicity due to osmotic diuresis requires infusion of hypotonic solutions. Prediction of the serum sodium after [Glu] normalization (the corrected [Na]) estimates the part of hypertonicity caused by osmotic diuresis. Theoretical methods calculating the corrected [Na] and clinical reports allowing its calculation were reviewed. Corrected [Na] was computed separately in reports of DKA, HHS and hyperglycemia in CKD stage 5. The theoretical prediction of [Na] increase by 1.6 mmol/L per 5.6 mmol/L decrease in [Glu] in most clinical settings, except in extreme hyperglycemia or profound hypervolemia, was supported by studies of hyperglycemia in CKD stage 5 treated only with insulin. Mean corrected [Na] was 139.0 mmol/L in 772 hyperglycemic episodes in CKD stage 5 patients. In patients with preserved renal function, mean corrected [Na] was within the eunatremic range (141.1 mmol/L) in 7,812 DKA cases, and in the range of severe hypernatremia (160.8 mmol/L) in 755 cases of HHS. However, in DKA corrected [Na] was in the hypernatremic range in several reports and rose during treatment with adverse neurological consequences in other reports. The corrected [Na], computed as [Na] increase by 1.6 mmol/L per 5.6 mmol/L decrease in [Glu], provides a reasonable estimate of the degree of hypertonicity due to losses of hypotonic fluids through osmotic diuresis at presentation of DKH or HHS and should guide the tonicity of replacement solutions. However, the corrected [Na] may change during treatment because of ongoing fluid losses and should be monitored during treatment.

Fluid treatment for children with diabetic ketoacidosis: How do the results of the pediatric emergency care applied research network Fluid Therapies Under Investigation in Diabetic Ketoacidosis (FLUID) Trial change our perspective?

The optimal fluid treatment protocol for children with diabetic ketoacidosis (DKA) has long been a subject of controversy. Until recently, there was no high-quality evidence from randomized clinical trials to support an optimal guideline, and recommendations were mainly based on theoretical considerations. As a consequence, fluid treatment protocols for children with DKA vary between institutions (and countries). In June 2018, the results from the Fluid Therapies Under Investigation in DKA Trial conducted in the Pediatric Emergency Care Applied Research Network were published. This large, factorial-designed randomized controlled trial assessed neurological outcomes of 1387 children with DKA who were treated with one of four fluid protocols that varied in infusion rate and sodium content. In this commentary, we review and discuss the results of this new study and the implications for clinical care of DKA in children.

Emergency Medicine Myths: Cerebral Edema in Pediatric Diabetic Ketoacidosis and Intravenous Fluids

BACKGROUND

Pediatric diabetic ketoacidosis (DKA) is a disease associated with several complications that can be severe. One complication includes cerebral edema (CE), and patients may experience significant morbidity with this disease.

OBJECTIVE

This review evaluates the myths concerning CE in pediatric DKA including mechanism, presentation of edema, clinical assessment of dehydration, and association with intravenous (i.v.) fluids.

DISCUSSION

Multiple complications may occur in pediatric DKA. CE occurs in < 1% of pediatric DKA cases, though morbidity and mortality are severe without treatment. Several myths surround this disease. Subclinical CE is likely present in many patients with pediatric DKA, though severe disease is rare. A multitude of mechanisms likely account for development of CE, including vasogenic and cytotoxic causes. Clinical dehydration is difficult to assess. Literature has evaluated the association of fluid infusion with the development of CE, but most studies are retrospective, with no comparator groups. The few studies with comparisons suggest fluid infusion is not associated with DKA. Rather, the severity of DKA with higher blood urea nitrogen and greater acidosis contribute to CE. Multiple strategies for fluid replacement exist. A bolus of 10 mL/kg of i.v. fluid is likely safe, which can be repeated if hemodynamic status does not improve.

CONCLUSIONS

Pediatric CE in DKA is rare but severe. Multiple mechanisms result in this disease, and many patients experience subclinical CE. Intravenous fluids are likely not associated with development of CE, and 10-mL/kg or 20-mL/kg i.v. bolus is safe.

[Diabetes emergencies]

Diabetes-associated emergencies are frequent and include hyperglycemic states, such as diabetic ketoacidosis (DKA) and hyperosmolar hyperglycemic state (HHS) as well as hypoglycemia (hypoglycemic coma) and metabolic disturbances that are unrelated to pathological blood glucose aberrations (lactic acidosis). Knowledge of the respective risk situations, key signs and symptoms as well as early detection, special aspects of intensive care treatment and procedures for the prevention of these diabetes emergency cases is a must not only for the duty doctor in intensive care but also for diabetologists, internists and family doctors in the outpatient situation. The basic facts on these issues are presented in this continuing medical education (CME) article in a didactically clear form.

Risk factors for mortality in children with diabetic keto acidosis from developing countries

Diabetic keto acidosis (DKA) is the major cause for mortality in children with Diabetes mellitus (DM). With increasing incidence of type 1 DM worldwide, there is an absolute increase of DM among children between 0-14 year age group and overall incidence among less than 30 years remain the same. This shift towards younger age group is more of concern especially in developing countries where mortality in DKA is alarmingly high. Prior to the era of insulin, DKA was associated with 100% mortality and subsequently mortality rates have come down and is now, 0.15%-0.31% in developed countries. However the scenario in developing countries like India, Pakistan, and Bangladesh are very different and mortality is still high in children with DKA. Prospective studies on DKA in children are lacking in developing countries. Literature on DKA related mortality are based on retrospective studies and are very recent from countries like India, Pakistan and Bangladesh. There exists an urgent need to understand the differences between developed and developing countries with respect to mortality rates and factors associated with increased mortality in children with DKA. Higher mortality rates, increased incidence of cerebral edema, sepsis, shock and renal failure have been identified among DKA in children from developing countries. Root cause for all these complications and increased mortality in DKA could be delayed diagnosis in children from developing countries. This necessitates creating awareness among parents, public and physicians by health education to identify symptoms of DM/DKA in children, in order to decrease mortality in DKA. Based on past experience in Parma, Italy it is possible to prevent occurrence of DKA both in new onset DM and in children with established DM, by simple interventions to increase awareness among public and physicians.

Pediatric diabetic ketoacidosis, fluid therapy, and cerebral injury: the design of a factorial randomized controlled trial

Treatment protocols for pediatric diabetic ketoacidosis (DKA) vary considerably among centers in the USA and worldwide. The optimal protocol for intravenous (IV) fluid administration is an area of particular controversy, mainly in regard to possible associations between rates of IV fluid infusion and the development of cerebral edema (CE), the most common and the most feared complication of DKA in children. Theoretical concerns about associations between osmotic fluid shifts and CE have prompted recommendations for conservative fluid infusion during DKA. However, recent data suggest that cerebral hypoperfusion may play a role in cerebral injury associated with DKA. Currently, there are no existing data from prospective clinical trials to determine the optimal fluid treatment protocol for pediatric DKA. The Pediatric Emergency Care Applied Research Network FLUID (FLuid therapies Under Investigation in DKA) study is the first prospective randomized trial to evaluate fluid regimens for pediatric DKA. This 13-center nationwide factorial design study will evaluate the effects of rehydration rate and fluid sodium content on neurological status during DKA treatment, the frequency of clinically overt CE and long-term neurocognitive outcomes following DKA.

Effect of normal saline and half normal saline on serum electrolytes during recovery phase of diabetic ketoacidosis

OBJECTIVE

This study aims to describe the effect of 0.9% saline (NS) versus 0.45% saline (half NS) when used during recovery phase of diabetic ketoacidosis (DKA) in children.

METHODS

A retrospective analysis of all children (1-18 years old) with DKA admitted in the pediatric intensive care unit (PICU) from 2005 to 2009 was undertaken. The primary end point was effect on serum electrolytes and acidosis.

RESULTS

Compared to 47 patients who received only NS (group A) throughout the recovery period and 33 patients who received NS but were switched to half NS (group B) at some point during recovery, 41 who received only half NS (group C) had a significant decrease in corrected serum sodium (P < .01). Hyperchloremia leading to nonanion gap acidosis was significantly greater in NS groups A and B than in half NS group C (P < .01). This led to increased duration of insulin infusion and length of stay in the PICU in the NS groups.

CONCLUSIONS

Hyperchloremia resulting in nonanion gap acidosis can occur and may prolong the duration of insulin infusion and length of PICU stay in patients receiving NS as post-bolus rehydration fluid. Alternatively, the use of half NS may result in a decrease in serum-corrected sodium. Providers need to be vigilant toward this while using higher or lower sodium chloride when managing children with DKA. Larger trials are required to study the clinical significance of the results of this study.

Brain edema in diseases of different etiology

Cerebral edema is a potentially life-threatening complication shared by diseases of different etiology, such as diabetic ketoacidosis, acute liver failure, high altitude exposure, dialysis disequilibrium syndrome, and salicylate intoxication. Pulmonary edema is also habitually present in these disorders, indicating that the microcirculatory disturbance causing edema is not confined to the brain. Both cerebral and pulmonary subclinical edema may be detected before it becomes clinically evident. Available evidence suggests that tissue hypoxia or intracellular acidosis is a commonality occurring in all of these disorders. Tissue ischemia induces physiological compensatory mechanisms to ensure cell oxygenation and carbon dioxide removal from tissues, including hyperventilation, elevation of red blood cell 2,3-bisphosphoglycerate content, and capillary vasodilatation. Clinical, laboratory, and necropsy findings in these diseases confirm the occurrence of low plasma carbon dioxide partial pressure, increased erythrocyte 2,3-bisphosphoglycerate concentration, and capillary vasodilatation with increased vascular permeability in all of them. Baseline tissue hypoxia or intracellular acidosis induced by the disease may further deteriorate when tissue oxygen requirement is no longer matched to oxygen delivery resulting in massive capillary vasodilatation with increased vascular permeability and plasma fluid leakage into the interstitial compartment leading to edema affecting the brain, lung, and other organs. Causative factors involved in the progression from physiological adaptation to devastating clinical edema are not well known and may include uncontrolled disease, malfunctioning adaptive responses, or unknown factors. The role of carbon monoxide and local nitric oxide production influencing tissue oxygenation is unclear.

Risk factors for cerebral edema in diabetic ketoacidosis in a developing country: role of fluid refractory shock

OBJECTIVES

To study the clinical profile and risk factors of cerebral edema in children with diabetic ketoacidosis with specific reference to fluid refractory shock.

DESIGN

Retrospective review of medical records.

SETTING

Twelve-bed pediatric intensive care unit of a teaching hospital.

PATIENTS

Seventy-seven patients admitted to pediatric intensive care unit with a diagnosis of diabetic ketoacidosis over 5 yrs.

INTERVENTION

Medical records were reviewed, and data with respect to patients' age, clinical features, biochemical profile (blood glucose, osmolality, electrolytes, urea, creatinine, arterial pH, PaCO(2), and HCO(3) at admission, 6-12 hrs, 24 hrs, and beyond 24 hrs), cerebral edema, presence of sepsis and shock, treatment details, and primary outcome in terms of survival or death were retrieved. Patients with and without cerebral edema were compared. Variables that were significant on univariate analysis were entered in a multiple logistic regression analysis to determine the predictors for cerebral edema. Odds ratio and 95% confidence interval were calculated using SPSS version 15.

MEASUREMENTS AND MAIN RESULTS

Mean age of the patients was 5.6 (standard deviation, 3.8) years. Fifty-five (71.4%) patients had new-onset diabetes mellitus. Cerebral edema was seen in 20 patients (26%). Blood glucose, serum osmolality, and CO(2) values at admission and rate of decline in glucose and osmolality during the first 12 hrs were similar in the cerebral edema and noncerebral edema groups. On multiple logistic regression analysis, fluid refractory shock (odds ratio, 7.3; 95% confidence interval, 1.3-41; p = .025) and presence of azotemia (odds ratio, 4.3; 95% confidence interval, 1.1-16; p = .034) at admission were predictors for development of cerebral edema. Mortality in cerebral edema group was 25% as compared to 3% in the noncerebral edema group.

CONCLUSIONS

Patients with fluid refractory shock and azotemia at admission had higher odds for development of cerebral edema. Initial blood glucose, effective osmolality, or decline in glucose and osmolality had no association with cerebral edema.

Insulin-resistant hyperglycaemia complicating neonatal onset of methylmalonic and propionic acidaemias

BACKGROUND

Insulin-resistant hyperglycaemia may occasionally complicate the clinical course of organic acidaemias.

STUDY DESIGN

Clinical observation.

RESULTS

Two term infants, one suffering from acute early-onset methylmalonic acidaemia, the other suffering from acute early-onset propionic acidaemia, presented acutely with dehydration, ketoacidosis, and hyperammonaemia. Urinary organic acid, plasma amino acids, and blood and plasma acylcarnitine analysis allowed the diagnosis of methylmalonic and propionic acidaemias. The detection of the novel c.481G>A (p.Gly161Arg) and the known c.655A>T (p.Asn219Tyr) MUT gene mutations identified the first patient as affected by methylmalonic acidaemia mut type. The high increase of propionylcarnitine after carnitine administration in both patients suggested a greatly elevated metabolic intoxication. Both newborns showed insulin-resistant hyperglycaemia. Patient 1 died, but patient 2, after a strong reduction of glucose administration, survived. To our knowledge, this is the only patient with this complication who survived.

CONCLUSION

Insulin-resistant hyperglycaemia complicating neonatal onset of methylmalonic and propionic acidaemias is probably a marker of a serious disease. One patient with this complication survived after a strong reduction of glucose administration. Even if this is probably only a partial intervention, we hypothesize that in this situation a reduction of glucose administration can reduce almost the risk of persistent hyperglycaemia. Further studies are required to confirm our hypothesis.

Cerebral edema in diabetic ketoacidosis

OBJECTIVE

To review the causes of cerebral edema in diabetic ketoacidosis (CEDKA), including pathophysiology, risk factors, and proposed mechanisms, to review the diagnosis, treatment, and prognosis of CEDKA and the treatment of diabetic ketoacidosis as it pertains to prevention of cerebral edema.

DATA SOURCE

A MEDLINE search using OVID was done through 2006 using the search terms cerebral edema and diabetic ketoacidosis. RESULTS OF SEARCH: There were 191 citations identified, of which 150 were used. An additional 42 references listed in publications thus identified were also reviewed, and two book chapters were used.

STUDY SELECTION

The citations were reviewed by the author. All citations identified were used except 25 in foreign languages and 16 that were duplicates or had inappropriate titles and/or subject matter. Of the 194 references, there were 21 preclinical and 40 clinical studies, 35 reviews, 15 editorials, 43 case reports, 29 letters, three abstracts, six commentaries, and two book chapters.

DATA SYNTHESIS

The data are summarized in discussion.

CONCLUSIONS

The causes and mechanisms of CEDKA are unknown. CEDKA may be due as much to individual biological variance as to severity of underlying metabolic derangement of the child's state and/or treatment risk factors. Treatment recommendations for CEDKA and diabetic ketoacidosis are made taking into consideration possible mechanisms and risk factors but are intended as general guidelines only in view of the absence of conclusive evidence.

An 18-yr prospective study of pediatric diabetic ketoacidosis: an approach to minimizing the risk of brain herniation during treatment

BACKGROUND

During the late 1900s, raised intracranial pressure (ICP) during treatment of pediatric diabetic ketoacidosis (DKA) surfaced as the most important cause of morbidity and mortality in pediatric DKA. The contribution of fluid and electrolyte therapy to neurologic deterioration during treatment remains controversial.

METHODS

We proposed a physiologic approach to treatment of DKA, incorporating the principles of rehydration of hypertonic states. Consecutive episodes of pediatric DKA were managed using continuous intravenous insulin, an individualized assessment of the degree of dehydration, and rehydration solutions of tonicity approximating that of the patient. Gradual replacement of the volume of deficit after correction of shock, if present, was planned over 48 h with special attention to changes in effective osmolality along with intensive cardiorespiratory, neurologic, and biochemical monitoring. Mannitol was given for signs or symptoms of raised ICP.

RESULTS

Six hundred and thirty-five consecutive episodes of pediatric DKA were treated from January 1988 to September 2005. Means +/- standard deviation (SD) for initial measured concentrations of total carbon dioxide, glucose, and urea nitrogen were 7.8 +/- 3.3 mmol/L, 602 +/- 271 mg/dL (33.4 +/- 15 mmol/L), and 21 +/- 1 mg/dL (7.4 +/- 3.6 mmol/L), respectively. Pretreatment blood gases were available for 477 episodes. The mean initial partial pressures of arterial and venous carbon dioxide +/- SD were 16.8 +/- 7 mmHg (kP(a)CO(2)= 2.24 +/- 0.93) for n = 308 and 26.6 +/- 7 mmHg (kP(v)CO(2)= 3.54 +/- 0.93) for n = 169, respectively. Although repair was planned to occur over 48 h, the mean time to achieve clinical rehydration and correction of DKA was 11.6 +/- 6.2 h. Mannitol was given in 35 (5.5%) episodes. There was no neurologic morbidity or mortality.

CONCLUSION

Management of pediatric DKA using this multifaceted physiologic approach and the principles of rehydration described is safe and appears to minimize the risk of brain herniation during treatment.

Preventing a drop in effective plasma osmolality to minimize the likelihood of cerebral edema during treatment of children with diabetic ketoacidosis

OBJECTIVES

To test whether a drop in effective plasma osmolality (P(Eff osm); 2 x plasma sodium [P(Na)] + plasma glucose concentrations) during therapy for diabetic ketoacidosis (DKA) is associated with an increased risk of cerebral edema (CE), and whether the development of hypernatremia to prevent a drop in the P(Eff osm) is dangerous.

STUDY DESIGN

This study is a retrospective comparison of a CE group (n = 12) and non-CE groups with hypernatremia (n = 44) and without hypernatremia (n = 13).

RESULTS

The development of CE (at 6.8 +/- 1.5 hours) was associated with a drop in P(Eff osm) from 304 +/- 5 to 290 +/- 5 mOsm/kg (P < .001). Control patients did not show this drop in P(Eff osm) at 4 hours (1 +/- 2 and 2 +/- 2 vs -9 +/- 2 mOsm/kg; P < .01), because of a larger rise in P(Na) and/or a smaller drop in plasma glucose. During this period, the CE group received more near-isotonic fluids (69 +/- 9 vs 35 +/- 2 and 27 +/- 3 mL/kg; P < .001). The CE group had a higher mortality (3/12 vs 0/57; P = .003), and more neurologic sequelae (5/12 vs 1/57; P < .001).

CONCLUSIONS

CE during therapy for DKA was associated with a drop in P(Eff osm). An adequate rise in P(Na) may be needed to prevent this drop in P(Eff osm).

Hyperglycemic crises and their complications in children

The object of this review is to provide the definitions and criteria for diabetic ketoacidosis (DKA) and the hyperglycemic hyperosmolar state (HHS), and convey current knowledge of the causes of permanent disability or mortality from complications of these conditions, of the risk factors for DKA and HHS, and of early indicators and contemporary treatment of suspected cerebral edema. The frequency of DKA at onset of type 1 diabetes mellitus (DM1) varies from 10-70%, depending on availability of health care and frequency of diabetes. At the onset of type 2 diabetes (DM2), DKA occurs in 5-52%. One study reported HHS in approximately 4% of new patients with DM2. Recurrent DKA rates are equally dependent on variability in medical services and socio-economic circumstances, and are estimated to be eight episodes per 100 patient years, with 20% of patients accounting for 80% of the episodes. Mortality for each episode of DKA internationally varies from 0.15-0.31%, with idiopathic cerebral edema accounting for two-thirds or more of this mortality. Other causes of death or disability include untreated DKA or HHS, hypokalemia, hypophosphatemia, hypoglycemia, other intracerebral complications, peripheral venous thrombosis, mucormycosis, rhabdomyolysis, acute pancreatitis, acute renal failure, sepsis, aspiration pneumonia, and other pulmonary complications. Population-based studies from the UK, Australia, the USA, and Canada report cerebral edema incidence in DKA of 0.5-2.0%. Published information does not support the notion that treatment factors are causal in cerebral edema. Younger age, greater severity of acidosis, degree of hypocapnia, and severity of dehydration have been suggested as risk factors in several studies. Bimodal distribution of the time of onset of cerebral edema and wide variation in brain imaging findings suggest the variability and likely multiple causation of the clinical picture. Functional brain scanning has indicated that DKA is accompanied by increased cerebral blood flow suggesting that the predominant mechanism of edema formation is a vasogenic process. A method of monitoring for diagnostic and major and minor signs of cerebral edema has been proposed and tested which indicates that intervention will be required in five individuals to provide early intervention for a single case of cerebral edema. The preferred intervention of mannitol infusion has typically been accompanied by intubation and hyperventilation, but recent evidence indicates outcome is adversely affected by aggressive hyperventilation. The prevention of DKA and HHS at the onset of diabetes mellitus requires a high degree of awareness and suspicion by primary care providers; prevention of recurrent DKA necessitates a diligent team effort.

The UK case-control study of cerebral oedema complicating diabetic ketoacidosis in children

AIMS/HYPOTHESIS

Cerebral oedema complicating diabetic ketoacidosis (DKA) remains the major cause of morbidity and mortality in children with type 1 diabetes, but its aetiology remains unknown. Our objective was to determine the impact of baseline biochemical factors and of treatment-related variables on risk of the development of cerebral oedema in children with DKA.

MATERIALS AND METHODS

This was a national UK case-control study. Through the British Paediatric Surveillance Unit we identified 43 cases of cerebral oedema. Through a parallel reporting system, we also identified 2,940 episodes of DKA and selected 169 control subjects on the basis of comparable age, sex, numbers of new or known cases of diabetes and date of admission. Baseline biochemical data and treatment-related variables were extracted from the clinical notes of cases and control subjects.

RESULTS

Allowing for differences in age, sex and new or known diabetes, cases were more acidotic at diagnosis of DKA (odds ratio [OR] for events in the least acidotic compared with the most acidotic tertile=0.02 [95% CI: 0.002-0.15], p<0.001). In addition, cases had higher potassium and urea levels at baseline. Calculated osmolality and baseline glucose were not significantly different. After allowing for severity of acidosis, insulin administration in the first hour (OR 12.7 [1.41-114.5], p=0.02) and volume of fluid administered over the first 4 h (OR 6.55 [1.38-30.97], p=0.01) were associated with risk. Low baseline plasma sodium and an elevated p(a)CO(2) also contributed to risk in the final regression model. Bicarbonate administration was not associated with increased risk of an event when corrected for acidosis.

CONCLUSIONS/INTERPRETATION

In this case-control study of DKA, baseline acidosis and abnormalities of sodium, potassium and urea concentrations were important predictors of risk of cerebral oedema. Additional risk factors identified were early administration of insulin and high volumes of fluid. These observations should be taken into account when designing treatment protocols.

Pediatric diabetic ketoacidosis and hyperglycemic hyperosmolar state

Diabetic ketoacidosis is an important complication of diabetes in children and is the most frequent diabetes-related cause of death in childhood. The pathophysiology of this condition can be viewed as an exaggeration of the normal physiologic mechanisms responsible for maintaining an adequate fuel supply to the brain and other tissues during periods of fasting and physiologic stress. The optimal therapy has been a subject of controversy, particularly because the most frequent serious complication of diabetic ketoacidosis-cerebral edema-and the relationship of this complication to treatment are incompletely understood. In this article, the author reviews the pathophysiology of diabetic ketoacidosis and its complications and presents an evidence-based approach to the management of this condition.

Population-based study of incidence and risk factors for cerebral edema in pediatric diabetic ketoacidosis

OBJECTIVES

To determine incidence, outcomes, and risk factors for pediatric cerebral edema with diabetic ketoacidosis (CEDKA) in Canada.

STUDY DESIGN

This was a case-control study nested within a population-based active surveillance study of CEDKA in Canada from July 1999 to June 2001. Cases are patients with DKA <16 years of age with cerebral edema. Two unmatched control subjects per case are patients with DKA without cerebral edema.

RESULTS

Thirteen cases of CEDKA were identified over the surveillance period for an incidence rate of 0.51%; 23% died and 15% survived with neurologic sequelae. CEDKA was present at initial presentation of DKA in 19% of cases. CEDKA was associated with lower initial bicarbonate ( P = .001), higher initial urea ( P = .001), and higher glucose at presentation ( P = .014). Although there was a trend to association with higher fluid rates and treatment with bicarbonate, these were not independent predictors.

CONCLUSIONS

CEDKA remains a significant problem with a high mortality rate. No association was found between the occurrence of CEDKA and treatment factors. The presence of cerebral edema before treatment of DKA and the association with severity of illness suggest that prevention of DKA is the key to avoiding this devastating complication.

Cerebral oedema in childhood diabetic ketoacidosis: is treatment a factor?

Cerebral oedema (CO) is the most dreaded complication of diabetic ketoacidosis (DKA) in children. Despite advances in many areas of the management of DKA, the mortality from CO has remained constant for decades. This rare disorder, complicating about 1% of cases of DKA in children, is lethal in 20% to 50% of victims. Since it was first described in 1936, much effort has gone into the search for a cause for this condition, but CO in childhood DKA remains a mysterious illness. Researchers have suggested that the treatment for DKA may be causally related to the development of CO. Others have disputed this claim, and both camps cite evidence to support their point of view. This article reviews the literature pertinent to the question: Is the treatment of DKA in children responsible for the development of CO?

Bumetanide reduces cerebral edema formation in rats with diabetic ketoacidosis

The mechanisms responsible for cerebral edema formation in diabetic ketoacidosis (DKA) are not well understood, although evidence suggests ischemia as a contributing factor. Previous studies have shown that the Na-K-Cl cotransporter of cerebral microvascular endothelial cells and astrocytes is a major participant in ischemia-induced cerebral edema in stroke. The present study was conducted to test the hypothesis that the Na-K-Cl cotransporter also contributes to cerebral edema in DKA. Sprague-Dawley rats were administered streptozotocin to induce DKA, and then cerebral edema was assessed by determination of apparent diffusion coefficients (ADC) with magnetic resonance diffusion-weighted imaging. Cerebral ADC values in DKA rats were significantly reduced in both cortex and striatum compared with non-DKA control rats, indicating the presence of cerebral edema. Intravenous administration of bumetanide to DKA rats abolished the drop in cortical ADC values, while having no significant effect in the striatum. Insulin and saline treatment had no effect when given after bumetanide but increased both cortical and striatal ADC values when given before bumetanide. Evidence is also presented here that acetoacetate and beta-hydroxybutyrate stimulate brain microvascular Na-K-Cl cotransporter activity. These findings suggest that the Na-K-Cl cotransporter contributes to brain edema in DKA.

Mechanism of cerebral edema in children with diabetic ketoacidosis

OBJECTIVES

Cerebral edema during diabetic ketoacidosis (DKA) has been attributed to osmotic cellular swelling during treatment. We evaluated cerebral water distribution and cerebral perfusion during DKA treatment in children.

STUDY DESIGN

We imaged 14 children during DKA treatment and after recovery, using both diffusion and perfusion weighted magnetic resonance imaging (MRI). We assessed the apparent diffusion coefficients (ADCs) and measures reflecting cerebral perfusion.

RESULTS

The ADC was significantly elevated during DKA treatment (indicating increased water diffusion) in all regions except the occipital gray matter. Mean reductions in the ADC from initial to postrecovery MRI were: basal ganglia 4.7 +/- 2.5 x 10(-5) mm(2)/s (P=.002), thalamus 3.7 +/- 2.8 x 10(-5) mm(2)/s, (P=.002), periaqueductal gray matter 4.3 +/- 5.1 x 10(-5) mm(2)/s (P=.03), and frontal white matter 2.0 +/- 3.1 x 10(-5) mm(2)/s (P=.03). In contrast, the ADC in the occipital gray matter increased significantly from the initial to postrecovery MRI (mean increase 3.9 +/- 3.9 x 10(-5) mm(2)/s, P=.004). Perfusion MRI during DKA treatment revealed significantly shorter mean transit times (MTTs) and higher peak tracer concentrations, possibly indicating increased cerebral blood flow (CBF).

CONCLUSIONS

Elevated ADC values during DKA treatment suggests a vasogenic process as the predominant mechanism of edema formation rather than osmotic cellular swelling.

Cerebral edema in childhood diabetic ketoacidosis: natural history, radiographic findings, and early identification

OBJECTIVE

Children who develop cerebral edema (CE) during diabetic ketoacidosis (DKA) exhibit definable signs and symptoms of neurological collapse early enough to allow intervention to prevent brain damage. Our objective was to develop a model for early detection of CE in children with DKA.

RESEARCH DESIGN AND METHODS

A training sample of 26 occurrences of DKA complicated by severe CE and 69 episodes of uncomplicated DKA was reviewed. Signs of neurological disease were incorporated into a bedside evaluation protocol that was applied to an independent test sample of 17 patients previously reported to have developed symptomatic CE during treatment for DKA. Head computed tomograms and their reports were reviewed.

RESULTS

The protocol allowed 92% sensitivity and 96% specificity for the recognition of CE sufficiently early for intervention. The diagnostic criteria were fulfilled in two temporal patterns, defining early- and late-onset CE. Although initial computed tomograms were often normal, the findings also included diffuse CE and focal brain injury, the latter only in patients with an early onset of abnormal neurological signs.

CONCLUSIONS

CE may occur in the absence of acute changes on head computed tomograms. Early detection of CE at the bedside using an evidence-based protocol permits intervention in time to prevent permanent brain damage.

ESPE/LWPES consensus statement on diabetic ketoacidosis in children and adolescents

Diabetic ketoacidosis (DKA) is the leading cause of morbidity and mortality in children with type 1 diabetes mellitus (TIDM). Mortality is predominantly related to the occurrence of cerebral oedema; only a minority of deaths in DKA are attributed to other causes. Cerebral oedema occurs in about 0.3-1% of all episodes of DKA, and its aetiology, pathophysiology, and ideal method of treatment are poorly understood. There is debate as to whether physicians treating DKA can prevent or predict the occurrence of cerebral oedema, and the appropriate site(s) for children with DKA to be managed. There is agreement that prevention of DKA and reduction of its incidence should be a goal in managing children with diabetes.

Cytokine response to diabetic ketoacidosis and its treatment

The objectives of this study were to monitor plasma cytokines as markers of cellular activation and as potential markers for the progression of the acute complications of diabetic ketoacidosis (DKA). Blood samples were obtained prior to, during and after treatment of severe DKA (pH < 7.2) in six children and adolescents. Plasma IL-10, IL-1beta, TNF-alpha, IL-6, IL-8 and IL-2 cytokine levels were assayed by ELISA at each of the time points. Prior to treatment, elevations of multiple cytokines were found, the highest being IL-10. Treatment of DKA resulted in a significant decrease of IL-10 at 6-8 h (p = 0.0062), and further increases in the inflammatory cytokines at 6-8 h and/or 24 h vs 120 h (baseline): IL-1beta (p =.0048); TNF-alpha (p =.0188) and IL-8 (p =.0048). This study strengthens the hypothesis that the metabolic crisis of DKA, and its treatment, have differential effects on cellular activation and cytokine release. The time frame for the increase in inflammatory cytokines correlates with the reported progression of subclinical brain edema, interstitial pulmonary edema and the development of clinical brain edema.

Effects of hydration and hyperventilation on cortical complexity

The effects of hydration and hyperventilation on cortical complexity were investigated in a sample of 19 healthy volunteers in a double-blind placebo design using magnetoencephalographic recordings. The subjects were asked to abstain from the intake of liquids 18 h before the study. Spontaneous magnetoencephalograms (MEG) were recorded before and after drinking 750 ml water (WAT group: nine subjects) or saline solution (SAL group: ten subjects) with eyes closed and open and during hyperventilation (HV) with eyes open. The MEG data were analysed using both linear (spectral power) and non-linear (pointwise dimension and largest Lyapunov exponent) algorithms. The prediction that intake of water, because of induced cell swelling, will lead to an increased synchronization and a decreased complexity of the spontaneous MEG during hyperventilation was confirmed. Hyperventilation following the drinking condition produced an increase in all power spectra with a stronger increase of delta and theta power after drinking of water. This synchronization of spontaneous MEG is accompanied by a general significant decrease of cortical complexity, especially after water drinking. Moreover, cortical complexity was inversely related to delta and theta power and partly also to alpha power. The SAL and WAT groups showed different relations between alpha power and dimensional complexity during HV: whereas in the SAL group the correlations between these measures became more negative during HV, they reversed in the WAT group to become positive. The synchronizing effect of hyperventilation, leading to a decrease of cortical complexity, is related in the SAL group to delta, theta and alpha power, whereas in the WAT group only delta and theta activity contribute to a reduction of cortical complexity.

Importance of timing of risk factors for cerebral oedema during therapy for diabetic ketoacidosis

Cerebral oedema is the most common cause of mortality and morbidity during the first day of conventional treatment for diabetic ketoacidosis in paediatric patients. It is possible that therapy contributes to its development. Risk factors that predispose to cerebral oedema should lead to an expansion of the intracellular and/or the extracellular fluid compartment(s) of the brain because water normally accounts for close to 80% of brain weight. With respect to the intracellular fluid compartment, the driving force to cause cell swelling is a gain of effective osmoles in brain cells and/or a significant decline in the effective osmolality of the extracellular fluid compartment. Factors leading to an expansion of the intracerebral extracellular fluid volume can be predicted from Starling forces acting at the blood-brain barrier. Some of these risk factors have an early impact, while others have their major effects later during therapy for diabetic ketoacidosis. Based on a theoretical analysis, suggestions to modify current therapy for diabetic ketoacidosis in children are provided.

Diabetic ketoacidosis and cerebral edema

Cerebral edema is the leading cause of death in children presenting in diabetic ketoacidosis and occurs in 0.2 to 1% of cases. The osmolar gradient caused by the high blood glucose results in water shift from the intracelluar fluid (ICF) to the extracellular fluid (ECF) space and contraction of cell volume. Correction with insulin and intravenous fluids can result in a rapid reduction in effective osmolarity, reversal of the fluid shift and the development of cerebral edema. The goals for treatment should be a combination of intravenous fluid and insulin that results in a gradual reduction of the effective osmolarity over a 36- to 48-hour period, thereby avoiding rapid expansion of the ICF compartment and brain swelling.

Prehospital cardiac arrest in diabetic ketoacidemia: why brain swelling may lead to death before treatment

An adolescent is reported with type 1 diabetes mellitus and diabetic ketoacidemia (DKA) who died from brain herniation prior to treatment with intravenous fluids and intravenous insulin. The pathophysiology of raised intracranial pressure (ICP) and water intoxication is discussed. As DKA evolves, water and electrolyte losses are replaced by very hypotonic fluids taken orally, leading to a physiologic excess of free water that would cause brain swelling prior to treatment. Central nervous system acidosis may interfere with normal compensatory mechanisms that help prevent small increases in ICP. The pathophysiology of pre-treatment brain swelling has important implications for rehydration with intravenous fluids and treatment with insulin. Prevention of DKA is paramount as well as complete postmortem evaluation of patients who die from this disease.

Effects of water on cortical excitability in humans

The effects of water on cortical excitability, measured using magnetoencephalographic recordings, were investigated in a sample of 19 healthy volunteers in a double-blind, placebo experiment comparing water with saline solution. Spontaneous magnetoencephalogram as well as auditory-evoked magnetic fields were recorded before and after the drinking of 750 mL water (9 subjects) or saline solution (10 subjects) and during and after hyperventilation following the drinking conditions. Hyperventilation was used to enhance the hypothesized synchronizing effect of water on spontaneous magnetoencephalographic activity. In addition, the magnetic fields were measured during a dichotic listening task under attended and unattended conditions. The prediction, that intake of water, because of induced cell swelling, will increase neuronal excitability and lead to an increased synchronization of the spontaneous magnetoencephalogram during hyperventilation was confirmed. Hyperventilation induced an increase of spectral power in all frequency bands particularly theta and delta power after water drinking. Furthermore, there was an increase of magnetic mismatch negativity (MMNm) amplitude in attended conditions and a simultaneous decrease in unattended conditions after water drinking. N1m (magnetic N1 wave) revealed significant changes during experimental conditions: increase after drinking and decrease after hyperventilation in both groups. MMNm for attended conditions showed a high positive correlation with osmolality changes (difference in the mol solute per kg water before and after drinking); N1m and PNm (magnetic processing negativity) as well as MMNm for unattended conditions showed significant correlations with subjective ratings of thirst and mood state.

Use of hypertonic saline in the treatment of cerebral edema in diabetic ketoacidosis (DKA)

Cerebral edema is the primary cause of morbidity and mortality in children and adolescents with diabetic ketoacidosis (DKA). We report a case of an adolescent female with life-threatening DKA-related cerebral edema who responded to a combination of mannitol and hypertonic saline. This is the first report of the use of hypertonic saline in the treatment of cerebral edema due to DKA.