Coagulation abnormalities in children undergoing epilepsy surgery

Effects of the ketogenic diet on platelet counts and global coagulation tests in childhood epilepsy

PURPOSE

Several antiseizure drugs (ASD), especially Valproic acid (VPA), influence platelet counts and coagulation parameters. The ketogenic diet (KD), established in drug-resistant epilepsy, is combined with ASDs. Bruising and prolonged bleeding times during KD have been described, but whether hemostatic changes result from the KD or from concomitant ASDs, remains unclear. Aim of the present study was to evaluate bleeding, platelet counts and global coagulation tests prior to and during KD in childhood epilepsy.

METHOD

Consecutive children treated with KD were systematically observed for bleeding. Serial measurements of platelet counts and global coagulation tests (APTT, PT and fibrinogen) were obtained at baseline and during KD (at 1, 3, 6 and 12 months). Children with KD monotherapy, concomitant VPA, or other ASDs were compared.

RESULTS

Among 162 children receiving KD, we observed neither bleeding in daily life nor perioperative bleeding in those undergoing surgery (n = 25). Most children had normal platelet counts and coagulation parameters. Only a few had transient mild thrombocytopenia and mildly prolonged APTT values, not indicative of a bleeding risk. Even KD combined with VPA did not cause relevant coagulopathy. Unexpectedly, we found mild thrombocytosis in 24 % of patients prior to KD, which was most pronounced in yet untreated epilepsy. Thrombocytosis steadily resolved during KD.

CONCLUSIONS

During KD treatment of childhood epilepsy, we observed neither bleeding symptoms nor laboratory results indicating a bleeding risk. Unexpectedly, mild thrombocytosis was present in 24 % at baseline, normalising during KD. Thrombocytosis may reflect the underlying inflammatory process of untreated epilepsy and requires further study.

Preoperative laboratory testing before pediatric neurosurgery: an NSQIP-Pediatrics analysis

OBJECTIVES

The goal of this study was to evaluate clinical predictors of abnormal preoperative laboratory values in pediatric neurosurgical patients.

METHODS

Data obtained in children who underwent a neurosurgical operation were extracted from the prospective National Surgical Quality Improvement Program-Pediatrics (NSQIP-P, 2012-2013) registry. Multivariable logistic regression evaluated predictors of preoperative laboratory values that might require further evaluation (white blood cell count < 2000/μl, hematocrit < 24%, platelet count < 100,000/μl, international normalized ratio > 1.4, or partial thromboplastin time > 45 seconds) or a preoperative transfusion (within 48 hours prior to surgery). Variables screened included patient demographics; American Society of Anesthesiologists (ASA) physical designation classification; comorbidities; recent steroid use, chemotherapy, or radiation therapy; and admission type. Predictive score validation was performed using the NSQIP-P 2014 data.

RESULTS

Of the 6556 patients aged greater than 2 years, 68.9% (n = 5089) underwent laboratory testing, but only 1.9% (n = 125) had a critical laboratory value. Predictors of a laboratory abnormality were ASA class III-V; diabetes mellitus; hematological, hypothrombotic, or oncological comorbidities; nutritional support; recent chemotherapy; systemic inflammatory response syndrome; and a nonelective hospital admission. These 9 variables were used to create a predictive score, with a single point assigned for each predictor. The prevalence of critical values in the validation population (NSQIP-P 2014) of patients greater than 2 years of age was 0.3% with a score of 0, 1.0% in those with a score of 1, 1.6% in those with a score of 2, and 6.2% in those with a score ≥ 3. Higher score was predictive of a critical value (OR 2.33, 95% CI 1.91-2.83, p < 0.001, C-statistic 0.76) and with the requirement of a perioperative transfusion (intraoperatively or within 72 hours postoperatively; OR 1.42, 95% CI 1.22-1.67, p < 0.001) in the validation population. Moreover, when the same score was applied to children aged 2 years or younger, a greater score was predictive of a critical value (OR 2.47, 95% CI 2.15-2.84, p < 0.001, C-statistic 0.76).

CONCLUSIONS

Critical laboratory values in pediatric neurosurgical patients are largely predicted by clinical characteristics, and abnormal preoperative laboratory results are rare in patients older than 2 years of age without comorbidities who are undergoing elective surgery. The NSQIP-P critical preoperative laboratory value scale is proposed to indicate patients with the highest odds of an abnormal value. The scale can assist with triaging preoperative testing based on the surgical risk, as determined by the treating surgeon and anesthesiologist.

Cardiopulmonary bypass considerations for pediatric patients on the ketogenic diet

BACKGROUND

There is a population of children with epilepsy that is refractory to anti-epileptic drugs. The ketogenic diet, a high-fat, low-carbohydrate regimen, is one alternative treatment to decrease seizure activity. Special considerations are required for patients on the ketogenic diet undergoing cardiopulmonary bypass (CPB) to prevent exposure to glucose substrates that could alter ketosis, increasing the risk of recurrent seizures.

CASE STUDY

A 2-year-old, 9 kilogram male with a history of infantile spasms with intractable epilepsy, trisomy 21 status post tetralogy of Fallot repair, presented to the cardiac operating room for closure of a residual atrial septal defect. All disciplines of the surgical case minimized the use of carbohydrate-containing and contraindicated medications. Changes to the standard protocol and metabolic monitoring ensured the patient maintained ketosis.

DISCUSSION

All disciplines within cardiac surgery need to be cognizant of patients on the ketogenic diet and prepare a modified protocol. Future monitoring considerations include thromboelastography, electroencephalography and continuous glucose measurement. Key areas of focus with this patient population in the cardiac surgical theater are to maintain a multidisciplinary approach, alter the required CPB prime components, address cardiac pharmacological concerns and limit any abnormal hematological occurrences.

High risk of gastrointestinal hemorrhage in patients with epilepsy: a nationwide cohort study

OBJECTIVE

To examine the association between epilepsy and gastrointestinal hemorrhage.

PATIENTS AND METHODS

We conducted a nationwide retrospective cohort study by using data from Taiwan's National Health Insurance Research Database. Patients 20 years and older newly diagnosed as having epilepsy and nonepileptic adults were identified between January 1, 2000, and December 31, 2003, and were observed through December 31, 2008. Cox proportional hazards models were performed to calculate adjusted hazard ratios (HRs) and 95% CIs of gastrointestinal hemorrhage associated with epilepsy.

RESULTS

Compared with the nonepileptic group (n=449,541), epileptic patients (n=1412) had a higher incidence of gastrointestinal hemorrhage (13.4 vs 2.9 per 1000 person-years), with an HR of 2.97 (95% CI, 2.49-3.53). The HRs of gastrointestinal hemorrhage for patients with generalized epilepsy, inpatient care, emergency care, and frequent outpatient visits for epilepsy were 3.50 (95% CI, 2.59-4.72), 3.96 (95% CI, 2.85-5.50), 4.35 (95% CI, 3.15-6.01), and 4.96 (95% CI, 3.97-6.21), respectively. Risks were significantly higher in epileptic patients with mental disorders (HR, 3.20; 95% CI, 2.55-4.01), aged 70 years and older (HR, 4.08; 95% CI, 2.89-5.77), and in the first year after epilepsy (HR, 4.81; 95%, CI, 3.14-7.34).

CONCLUSION

Epilepsy is an independent determinant for gastrointestinal hemorrhage in a chronological and severity-dependent pattern. We urge the development of an adequate surveillance policy and strategy for the early prevention of gastrointestinal hemorrhage in epileptic patients.