Current state of hemispherectomy and callosotomy for pediatric refractory epilepsy in Denmark

OBJECTIVE

To evaluate outcomes from hemispherectomy and callosotomy related to the need for anti-seizure medication (ASM), seizure frequency, and cognition.

METHODS

A review of the medical charts of all Danish pediatric patients who underwent hemispherectomy or callosotomy from January 1996 to December 2019 for preoperative and postoperative ASM use, seizure frequency, and cognitive data.

RESULTS

The median age of epilepsy onset was two years (interquartile range (IQR): 0.0-5.3) for the hemispherectomy patients (n = 16) and one year (IQR: 0.6-1.7) for callosotomy patients (n = 5). Median time from onset to final surgery was 3.4 years for hemispherectomy and 10.2 years for callosotomy, while the median follow-up time was 6.9 years and 9.0 years, respectively. Preoperatively, all patients had daily seizures and were treated with ≥ 2 ASM. Hemispherectomy resulted in a reduction in seizure frequency in 87.5 % of patients, with 78.6 % achieving seizure freedom. Furthermore, 81.3 % experienced a reduction in ASM use and 56.3 % stopped all ASM. Median IQ/developmental quotient (IQ/DQ) was low preoperatively (44.0 [IQR: 40.0-55.0]) and remained unchanged postoperatively (IQ change: 0.0 [IQR: -10.0-+4.0]). Callosotomy resulted in a seizure reduction of 86-99 % in four patients, and ASM could be reduced in three patients. Median IQ/DQ was 20.0 preoperatively (IQR: 20.0-30.0) and remained unchanged postoperatively (IQ change: 0.0 [IQR: 0.0]).

CONCLUSION

Hemispherectomy and callosotomy result in a substantial reduction in seizure frequency and ASM use without deterioration of IQ. Extensive epilepsy surgery should be considered early in children with drug-resistant epilepsy.

Increase in cognitive function is seen in many single-operated pediatric patients after epilepsy surgery

PURPOSE

The recurrent seizures of pediatric drug-resistant epilepsy (DRE) are known to impair brain development and can lead to a loss in cognitive functioning. Surgery is increasingly being used to treat children with DRE. This study investigates the pre- and postoperative cognitive function in a pediatric epilepsy surgery cohort as well as predictive determinants of change in intelligence quotient (IQ) following surgery.

METHODS

A consecutive series of 91 Danish children who underwent focal resective epilepsy surgery between January 1996 and December 2016 were included. All underwent preoperative cognitive evaluation and were reevaluated at 1-year and/or 2-year follow-up. Single-operated and multi-operated patients were examined separately.

RESULTS

79 of 91 patients were single-operated. Single-operated patients received less anti-epileptic drugs (AED) and experienced a decrease in seizure frequency postoperatively, p < 0.001. IQ increased postoperatively (IQ change ± standard deviation: 3.3 ± 14.0), p < 0.05. High preoperative seizure frequency was a significant predictor for decreased IQ, p < 0.01. Multi-operated patients did not experience a reduction in AED treatment. Surgery and continued AED treatment did, however, result in significantly better seizure control, p < 0.01. IQ remained unchanged in multi-operated patients.

CONCLUSION

Epilepsy surgery allowed for IQ gains in single-operated patients. Preoperative seizure frequency was a significant predictor of IQ change following surgery. Interactions between other, not included, possible predictors remain to be examined. Single-operated patients had the best cognitive outcome. The inclusion of a non-surgical control group is needed to assess the extent of the beneficial effects of surgery on cognitive ability.

Preventing medication errors in community pharmacy: frequency and seriousness of medication errors

BACKGROUND

Medication errors are a widespread problem which can, in the worst case, cause harm to patients. Errors can be corrected if documented and evaluated as a part of quality improvement. The Danish community pharmacies are committed to recording prescription corrections, dispensing errors and dispensing near misses. This study investigated the frequency and seriousness of these errors.

METHODS

40 randomly selected Danish community pharmacies collected data for a defined period. The data included four types of written report of incidents, three of which already existed at the pharmacies: prescription correction, dispensing near misses and dispensing errors. Data for the fourth type of report, on adverse drug events, were collected through a web-based reporting system piloted for the project.

RESULTS

There were 976 cases of prescription corrections, 229 cases of near misses, 203 cases of dispensing errors and 198 cases of adverse drug events. The error rate was 23/10,000 prescriptions for prescription corrections, 1/10,000 for dispensing errors and 2/10,000 for near misses. The errors that reached the patients were pooled for separate analysis. Most of these errors, and the potentially most serious ones, occurred in the transcription stage of the dispensing process.

CONCLUSION

Prescribing errors were the most frequent type of error reported. Errors that reached the patients were not frequent, but most of them were potentially harmful, and the absolute number of medication errors was high, as provision of medicine is a frequent event in primary care in Denmark. Patient safety could be further improved by optimising the opportunity to learn from the incidents described.

Preventing medication errors in community pharmacy: root-cause analysis of transcription errors

BACKGROUND

Medication errors can have serious consequences for patients, and medication safety is essential to pharmaceutical care. Insight is needed into the vulnerability of the working process at community pharmacies to identify what causes error incidents, so that the system can be improved to enhance patient safety.

METHODS

40 randomly selected Danish community pharmacies collected data on medication errors. Cases that reached patients were analysed, and the most serious cases were selected for root-cause analyses by an interdisciplinary analysis team.

RESULTS

401 cases had reached patients and a substantial number of them had possible clinical significance. Most of these errors were made in the transcription stage, and the most serious were errors in strength and dosage. The analysis team identified four root causes: handwritten prescriptions; "traps" such as similarities in packaging or names, or strength and dosage stated in misleading ways; lack of effective control of prescription label and medicine; and lack of concentration caused by interruptions.

CONCLUSION

A substantial number of the medication errors identified at pharmacies that reach patients have possible clinical significance. Root-cause analysis shows potential for identifying the underlying causes of the incidents and for providing a basis for action to improve patient safety.

M-mode echocardiography in aortic stenosis. Clinical correlates and prognostic significance after valve replacement

To relate preoperative findings at M-mode echocardiography to preoperative clinical and haemodynamic status and to identify possible echocardiographic risk factors for mortality after aortic valve replacement (AVR), 250 patients with AVR for aortic stenosis (AS) were studied. In follow-up averaging 3.2 years there were 22 early (< 30 days) and 23 late deaths. Rising NYHA function class and cardiothoracic index, and left ventricular (LV) failure were related to rising LV end-diastolic and end-systolic diameter index (EDDI, ESDI), and to increasing LV muscle mass index and decreasing fractional shortening (FS). High peak-to-peak systolic aortic valve gradient and LV end-systolic pressure were related to small dimensions of LV with increased FS and posterior wall thickness (PWTh). EDDI < or = 20 mm/m2 and increasing PWTh were independent risk factors for early mortality. Patients with EDDI < or = 20 mm/m2 had normal or supranormal FS. PWTh was the only independent risk factor in long-term survival: 5-year rates being 81 +/- 6%, 94 +/- 3% and 85 +/- 7% for PWTh < or = 13, 14-17 and > or = 18 mm, respectively (p = 0.03). Prevalence of concomitant coronary artery disease (CAD) rose with decreasing PWTh. Angina pectoris in non-CAD patients was related to very high PWTh. Subnormal EDDI was associated with poor surgical outcome, and dilated, poorly contracting LV with congestive heart failure prior to AVR. The degree of LV hypertrophy seemed to be the dominant risk factor, but confounders included myocardial ischaemia due to CAD in low-grade hypertrophy or to hypertrophy per se. A hypothetically confounding factor is the reversibility potential of moderate or severe LV hypertrophy following AVR.

The potential for normal long term survival and morbidity rates after valve replacement for aortic stenosis

BACKGROUND AND AIM OF THE STUDY

The sequelae of early aortic valve replacement (AVR) for aortic stenosis (AS) are controversial, with an increasing body of opinion regarding the patient risk profile as having an influence on long term survival and prosthesis-related morbidity rates. We therefore undertook a comparison of the morbidity and mortality rates of the patients undergoing AVR at our institution over a 22 year period with those in the background population to establish whether early intervention leads to an increased incidence of either.

METHODS

A multivariate risk analysis of 630 consecutive patients with AS who were alive 30 days after AVR performed between January 1965 and December 1986 was completed. The patients had a mean age of 59 years (range 14-78 years), 98% received a mechanical prosthetic valve, and 71% were in functional classes III or IV preoperatively.

RESULTS

Relative to an age- and sex-matched background population, the patients suffered a slight excess mortality during the first postoperative year, and a significant excess mortality after the 12th year, which was primarily related to congestive heart failure (64% of deaths versus 25% during the first 12 years; p < 0.01). A multivariate Cox regression model allowed calculation of a prognostic index for each patient. The index divided the patients into three groups (from low to high index): group A (n = 195) had normal sex- and age-specific survival, group B (n = 165) had a slight late (> 12th year) excess mortality, while group C (n = 270) had significant excess mortality throughout the follow up. Multivariate risk analysis of thromboembolism (1.7%/pt-yr), anticoagulant related hemorrhage (1.5%/pt-yr), all prosthesis-related complications combined (4.2%/pt-yr), and sudden cardiac events (arrhythmia and myocardial infarct; 1.8%/pt-yr) identified variables underlying advanced preoperative heart disease, coronary artery disease and systemic hypertension as the decisive risk factors. The preoperative prevalence of these risk factors as well as the postoperative incidence of the complications differed significantly between the three patient groups; A < B < C. Incidence rates of stroke in the patients (95% confidence interval) and in sex- and age-matched background populations were: group A, 0.48 (0.13-0.83) and 0.34 %/pt-yr, respectively, group B, 1.07 (0.46-1.68) and 0.52%pt-yr, respectively, and group C, 2.28 (1.50-3.06) and 0.68%/pt-yr respectively. Similar results were obtained for incidence rates of myocardial infarct.

CONCLUSION

Operative intervention early in the course of AS, being equivalent to a favorable risk profile, may result in an age- and sex-specific normal long term survival, generally low rates of prosthesis-related complications and a normal incidence of the dominant thromboembolic and hemorrhagic events and of myocardial infarction.

Influence of pre-existing ischemia on recovery from chemical cardioplegia. A study on pig hearts in an isolated blood-perfused model

The impact of prior cardiac ischemia on recovery from chemical cardioplegia was investigated in pig hearts. Group I hearts were subjected to 9-min normothermic ischemia before the start of chemical cardioplegia. After 180 min of induced cardiac arrest, all hearts were reperfused and monitored for 120 min in a blood-perfused Langendorff model. Consistent with left ventricular performance, myocardial oxygen uptake was significantly lower in group I than in the other hearts during the first 60 min of reperfusion. Lactate elimination was significantly higher in group I at the start of reperfusion, but showed no intergroup difference after 25 min. Nor was intergroup difference found in left ventricular end-diastolic pressure, total myocardial flow or glucose extraction fraction during reperfusion. The mitochondrial ultrastructure was identical in the two groups before chemical cardioplegia. During cardioplegia it deteriorated in group I but normalized in group II. During reperfusion these circumstances were reversed. Although precardioplegic ischemia thus significantly impaired left ventricular performance during early recovery, with corresponding effects on metabolism and ultrastructure, stable performance during reperfusion indicated that the ischemic injury did not worsen.

Estimation of tissue blood flow from hyperthermia treatment data

During hyperthermia treatment of patients the delivered heat and the temperatures at several points in the tissue are often measured and recorded. These data contain information about thermal tissue parameters. A method for extracting this information, i.e. estimating the tissue parameters--in particular the blood perfusion rate--is described. The method applies a system identification technique, adjusting the unknown parameters in a thermal tissue model, until the predicted model output (temperature) coincides well with the measured temperature. Data from a number of patient treatments have been used to test the method, and although the accuracy of the method remains to be established conclusively it appears to give a good estimate of the model parameter representing blood flow. The obvious advantage of the method is that it requires no special transducers or experiments. The weak aspect is that it depends on the correctness of a thermal model of the perfused tissue.

Two-point control of temperature profile in tissue

A strategy for controlling the temperature profile in the tissue with a single applicator hyperthermia system is described. By manipulating the cooling water temperature as well as the heating power, the tissue temperatures in two selected locations can be controlled. By proper choice of these two locations and the corresponding temperature set-points, a temperature maximum can be obtained in a fairly superficial tumour. If the tissue composition and consequently the temperature distribution is fairly regular, a temperature profile above 43 degrees C in the tumour and below that in normal tissue can be obtained along an axis perpendicular to the surface. The controller is self-tuning and provides dynamic decoupling, bumpless transfer and anti-reset windup. Test of the controller by simulation and on a phantom indicates it is superior to the single point controller currently used.

State hospital review boards in Minnesota

For the past eight years Minnesota has had a review board for each state hospital serving the mentally ill and the mentally retarded. Each board consists of at least three individuals appointed by the commissioner of the department of public welfare. The board is an external review body in that members are not associated with the department or with the state hospital. It visits the hospital as frequently as required to review commitment papers and processes, assess the propriety of treatment procedures, ensure that each patient has an individualized treatment plan, interview patients and record their concerns, conduct a random review of patients' records, and meet with hospital staff. The board reports its findings to the commissioner and to the head of the hospital.