Awake seizures after pure sleep-related epilepsy: a systematic review and implications for driving law.

Who with sleep seizures is safe to drive? Driving law is controversial; ineligibility varies between individual US states and EU countries. Current UK driving law is strongly influenced by a single-centre study from 1974 where most participants were not taking antiepileptic drugs (AEDs). However, pure sleep-related epilepsy is often fully controlled on medication, and its withdrawal can provoke awake seizures. This systematic review asked, 'What is the risk of awake seizures in pure sleep-related epilepsy?' 9885 titles were identified; 2312 were excluded (not human or adult); 40 full texts were reviewed; six papers met our inclusion criteria; each of these six studies had a different pure sleep-related epilepsy definition. Using the largest prospective study, we were able to calculate next year's awake seizure chance (treated with antiepileptic medication). This was maximal in the second year: 5.7% (95% CI 3.0 to 10.4%). European licensing bodies including the UK's Driver and Vehicle Licensing Agency broadly accept a risk of less than 20% for Group 1 licensing. However, this study excluded patients with frontal-lobe epilepsies. Furthermore, follow-up (n=160) varied from 2 to 6 years, yet new awake seizures may occur even after 10-20 years of pure sleep-related epilepsy A paucity of evidence underpins present licensing law; current rulings would be difficult to defend if legally challenged. The law may be penalising people with pure sleep-related epilepsy without increased risk of awake seizures, while failing to identify subgroups at unacceptable risk of an awake seizure at the wheel.

What level of on-call cover is required to allow trainees to meet minimum faculty requirements?

BACKGROUND: We investigated whether trainees' out-of-hours experience in Wales is sufficient to allow them to meet Faculty training requirements. We also determined how much time on call, covering what population, allows trainees to meet these requirements. METHODS: Using Welsh on-call audit data, we inferred the number of calls that trainees would receive during training and compared this with requirements for on-call experience. We generalized the analysis to examine the effect of changes in the population size covered and the length of time on call on the likelihood of trainees meeting minimum requirements. RESULTS: Trainees in Wales can expect to achieve most on-call faculty requirements. However, the expected number of contacts with the Health Protection Agency, 0.95 [95% confidence interval (CI): 0.024-5.281], and Environmental Health, 1.90 (95% CI: 0.230-6.848), imply that trainees may have difficulty achieving requirement 2.4. For different requirements at a set population size, widely disparate lengths of time are necessary to be 95% certain of achievement. CONCLUSIONS: Most on-call requirements can be readily achieved in Wales, but contact with other professional groups (requirement 2.4) cannot be guaranteed. Further analysis suggests that requirement 2.4 is unlikely to be achieved except at unrealistic times on the on-call rota covering unrealistic populations.

Awake intubation of the adult trachea using the Bullard laryngoscope.

Awake intubation using the Bullard laryngoscope can be comfortably and easily performed in the adult. Five cases are presented in which tracheal intubation was performed under topical anaesthesia with light intravenous sedation. In each case, topical anaesthesia was performed by insertion of a Guedel oral airway, with lidocaine ointment applied to the inferior and posterior surfaces. In one case, Bullard intubation was successful where direct laryngoscopy and multiple attempts at bronchoscopic intubation by three different operators had failed. We conclude that the Bullard laryngoscope can be easily used in awake patients and may be a useful alternative where other methods for awake intubation have failed.

An in vitro evaluation of ionized calcium levels and clotting in red blood cells diluted with lactated Ringer's solution.

The addition of lactated Ringer's solution which contains calcium (RL) to citrated blood products poses a potential risk whenever the level of ionized calcium reaches a concentration capable of catalyzing the coagulation cascade. RL solution is used extensively as both a replacement and a maintenance fluid in the operating room. However, major surgical procedures often require replacement of blood components as well, during the operation. This study examines the in vitro propensity for coagulation when red blood cells (RBC) are diluted with RL. Seven mixtures with different ratios of RBC to RL were prepared from each of 23 units of RBC. These mixtures were analyzed for ionized calcium, total calcium, and pH, and were checked for any indication of coagulation. Nineteen additional RBC units were split into two parts which were mixed with equal volumes of normal saline (NS) or RL. These mixtures were filtered (40 micron) and the weight gain of the paired filters compared. From these studies, the authors identified a threshold value for ionized calcium (0.23 mM/L) below which the probability of clot formation is less than 0.01. This concentration is not reached if the RBC to RL volume ratio is 2:1 or greater. As much as 100 ml of RL can be added to a unit of RBC without exceeding the threshold value. Although not advocating the routine use of RL as a diluent for RBC, the authors conclude that, within the guidelines described, calcium containing salt solutions may be used to dilute blood products.

Coronary risk factors in flying personnel: a progress report.

Since October 1974, the Flight Surgeon's Office at the USAF Hospital Dover has implemented a program of early detection and treatment of coronary risk factors in aircrew personnel. The program is integrated with USAF periodic physical examinations with interval follow-up of members found to have possible risk factors. A report of initial (baseline) findings was presented at the Aerospace Medical Association meeting in May 1975. During the past year, the base did experience one death due to myocardial infarction in an aircrew member, while two others were grounded due to serial ECG changes, consistent with silent myocardial infarction, confirmed by review at the USAF-SAM ECG Library.

Antihypertensive drug therapy in USAF flying personnel.

The reviewed data concerns hypertensive USAF aircrew members, as available from the WAVR File (July 1973) and the records of the Aeromedical Consultation Service at USAFSAM (1 July 1972-30 June 1973). Of over 6,500 entries in the WAVR File, hypertension was listed as a diagnosis for 754 individuals. Drug therapy had been instituted in 379 cases (50.3%) of the total. Statistics regarding ranks, age groups, and aeronautical ratings are presented. The group included 520 pilots, of whom 268 were receiving drug therapy. Associated medical conditions, e.g., abnormal EKG findings, carbohydrate intolerance, and hyperuriciemia, are presented. Similar data are reviewed for the 84 patients evaluated on the Aeromedical Consultation Service (USAFSAM).