Adverse drugs reactions (ADR) suspected through phone triage and assessed by medically staffed ambulances: A pilot study.

BACKGROUND: Prompt and definitive diagnosis of adverse drug reactions (ADRs) is a challenge for health care providers. There is a global burden of ADRs worldwide associated with a negative impact on the patient's health, in parallel with increasing costs for the community. This study aims to determine the annual incidence of ADRs in the cohort of patients requiring immediate intervention of the French prehospital emergency medical service (PEMS). The definitive diagnosis of ADR was provided by the follow-up of the entire course of hospitalization from PEMS presentation to final discharge in each suspected case. METHODS: A retrospective study examining the incidence of ADR at the Paris PEMS was performed in 2015. RESULTS: From January the 1st to December the 31st, 2015, 485 cases of suspected ADR were selected. Twenty-eight patients could not be identified at the hospital and were considered as lost to follow-up. For the 457 cases with the final diagnosis and outcome available, 359 had a definitive and new diagnosis of ADR, 9 were related to substance of abuse and alcohol, 14 were duplicates and 75 were excluded by drug causality was ruled out. Long-term follow-up was performed for 359 cases. Among them, 22 patients (6.1%) died of an ADR. Twenty-five severe ADRs were notified for children ages 2 to 16 with a cluster of 9 cases (36%) resulting from an accidental outbreak of poisonings with alimemazine in a classroom. No fatality was reported among children suffering from an ADR. CONCLUSION: The collaboration between PEMS and in hospital Pharmacovigilance Centre is feasible from the PEMS report to the long-term follow-up. The definition of a clinical pattern for some drugs is needed to allow the medical team to anticipate the clinical outcome of the involved patient and therefore adapting the patient's support as soon as possible.

"Unusual Pattern of Cerebral Microbleeds and Petechial Hemorrhages after Veno-Arterial Extracorporeal Membrane Oxygenation Support. A Report of 2 Cases".

OBJECTIVE: to report an unusual pattern of brain petechial hemorrhages in 2 patients after veno-arterial extracorporeal membrane oxygenation support (VA-ECMO) CASE 1: a 28-year-old man (Marfan disease) presented in the early post-operative period a multi-organ failure associated with a disseminated intravascular coagulation (DIC). He was placed on continuous veno-venous hemofiltration and VA-ECMO. He was weaned from ECMO 4 days later. He then developed bacterial pneumoniae leading to respiratory failure and requiring mechanical ventilation. MRI 30 days later showed widespread petechial hemorrhages in the subcortical and deep white matter (WM) (optic radiations, corpus callosum, predominantly in the splenium, internal and external capsules), caudate nuclei, basal ganglia, frontal and parietal cortex and in infratentorial structures. These hemorrhages were bilateral and almost symmetric and marked at the border zones of the carotid arteries territories. CASE 2: a 60-year-old man presented an out-of-hospital refractory hypothermic cardiac arrest. At arrival, cardiopulmonary resuscitation was continued; he presented bleeding at the puncture sites related to DIC and associated with multi-organ failure. VA-ECMO was implanted. After ECMO removal (day 7) he presented a severe spatial orientation deficit. MRI showed petechial hemorrhages in both hippocampi and microbleeds at the cerebral cortex and the juxta-cortical WM. Both patients had good functional outcome. CONCLUSION: Two unusual presentations of brain hemorrhages in patients who underwent VA-ECMO are reported. If their specific cause remains unclear, there seems to be a relationship in time between DIC and microhemorrhages in these cases, even if in case 1 brain hemorrhages seem to have a multifactorial cause.

Evaluating lactate prognostic value in children suspected of acetaminophen-induced liver failure in Liberia.

BACKGROUND: The prognostic significance of hyperlactatemia in young children with liver injury suspected to be attributed to repeated supratherapeutic doses of acetaminophen remain understudied. METHODS: We conducted a retrospective medical chart review including children aged <5 years admitted with hepatocellular injury. The study was conducted in Bardnesville Junction Hospital operated by Médecins Sans Frontières in Monrovia, Liberia. RESULTS: We analyzed 95 children with liver injury in whom a blood lactate measurement on admission was available. Eighty children (84%) were aged <2 years; 49 children (52%) died during hospitalization. The median acetaminophen concentration on admission was 20 mg/L with 60 (70%) children presenting concentrations exceeding 10 mg/L. Median lactate was significantly higher in children who died (10.7 mmol/L; interquartile range (IQR): 8.5-15.7) than those who survived (6.1 mmol/L; IQR: 4.1-8.5), P value < 0.001). The optimal threshold obtained was 7.2 mmol/L with a sensitivity of 84% and specificity 70% (area under curve = 0.80). The previously established thresholds of 3.5 and 4 mmol/L lactate had very low specificity identifying non-survival in children included in this study. CONCLUSION: In this setting, young children with ALF possibly attributed to acetaminophen toxicity were unlikely to survive if the venous blood lactate concentration exceeded 7.2 mmol/L.

Correction to: Suspected paracetamol overdose in Monrovia, Liberia: a matched case-control Study.

An amendment to this paper has been published and can be accessed via the original article.

Suspected paracetamol overdose in Monrovia, Liberia: a matched case-control study.

BACKGROUND: A cluster of cases of unexplained multi-organ failure was reported in children at Bardnesville Junction Hospital (BJH), Monrovia, Liberia. Prior to admission, children's caregivers reported antibiotic, antimalarial, paracetamol, and traditional treatment consumption. Since we could not exclude a toxic aetiology, and paracetamol overdose in particular, we implemented prospective syndromic surveillance to better define the clinical characteristics of these children. To investigate risk factors, we performed a case-control study. METHODS: The investigation was conducted in BJH between July 2015 and January 2016. In-hospital syndromic surveillance identified children with at least two of the following symptoms: respiratory distress with normal pulse oximetry while breathing ambient air; altered consciousness; hypoglycaemia; jaundice; and hepatomegaly. After refining the case definition to better reflect potential risk factors for hepatic dysfunction, we selected cases identified from syndromic surveillance for a matched case-control study. Cases were matched with in-hospital and community-based controls by age, sex, month of illness/admission, severity (in-hospital), and proximity of residence (community). RESULTS: Between July and December 2015, 77 case-patients were captured by syndromic surveillance; 68 (88%) were under three years old and 35 (46%) died during hospitalisation. Of these 77, 30 children met our case definition and were matched with 53 hospital and 48 community controls. Paracetamol was the most frequently reported medication taken by the cases and both control groups. The odds of caregivers reporting supra-therapeutic paracetamol consumption prior to admission was higher in cases compared to controls (OR 6.6, 95% CI 2.1-21.3). Plasma paracetamol concentration on day of admission was available for 19 cases and exceeded 10 µg/mL in 10/13 samples collected on day one of admission, and 4/9 (44%) collected on day two. CONCLUSIONS: In a context with limited diagnostic capacity, this study highlights the possibility of supratherapeutic doses of paracetamol as a factor in multi-organ failure in a cohort of children admitted to BJH. In this setting, a careful history of pre-admission paracetamol consumption may alert clinicians to the possibility of overdose, even when confirmatory laboratory analysis is unavailable. Further studies may help define additional toxicological characteristics in such contexts to improve diagnoses.

Safety and Efficacy of New Oximes to Reverse Low Dose Diethyl-Paraoxon-Induced Ventilatory Effects in Rats.

BACKGROUND: Oximes are used in addition to atropine to treat organophosphate poisoning. However, the efficiency of oximes is still a matter of debate. In vitro experiments suggested than new oximes are more potent than the commercial oximes. However, the antidotal activity of new oximes has not been assessed in vivo. METHODS: The aim of this work was to assess the safety and efficiency of new oximes compared to pralidoxime in a rat model of diethyl paraoxon-induced non-lethal respiratory toxicity. RESULTS: Safety study of oximes showed no adverse effects on ventilation in rats. KO-33, KO-48, KO-74 oximes did not exhibit significant antidotal effect in vivo. In contrast, KO-27 and BI-6 showed evidence of antidotal activity by normalization of respiratory frequency and respiratory times. KO-27 became inefficient only during the last 30 min of the study. In contrast, pralidoxime demonstrated to be inefficient at 30 min post injection. Inversely, the antidotal activity of BI-6 occurred lately, within the last 90 min post injection. CONCLUSION: This study showed respiratory safety of new oximes. Regarding, the efficiency, KO-27 revealed to be a rapid acting antidote toward diethylparaoxon-induced respiratory toxicity, meanwhile BI-6 was a late-acting antidote. Simultaneous administration of these two oximes might result in a complete and prolonged antidotal efficiency.

Determinants of Lactic Acidosis in Acute Cyanide Poisonings.

OBJECTIVES: To investigate the magnitude of lactic acidosis in response to cyanide poisoning compared with the secondary response caused by cardiovascular shock. DESIGN: Retrospective case-control observational study. SETTING: University Hospital of Assistance Publique - Hôpitaux de Paris. SUBJECTS: Patients admitted for suspicion of cyanide poisoning or drug overdose. Medical charts provided by Assistance Publique - Hôpitaux de Paris of patients between January 1988 and December 2015. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Twelve cyanide poisoned patients were matched to 48 controls by age, sex, systolic blood pressure, catecholamine administration, and outcome at discharge from ICU. Extracted data included age, sex, vital signs, symptoms, biochemical parameters, toxicological analysis, treatment, and outcome. Non-parametric tests were used. Multivariable analysis was used to adjust for confounders causing hyperlactacidemia. The median blood lactate concentration was significantly greater in the cyanide group (15.6 mmol/L) compared to the control group (4.1 mmol/L; p = 0.0003). Similarly, blood lactate concentration greater than or equal to 8 mmol/l was observed in 83% of the cyanide cases versus 27% of the matched controls. Multivariate analysis conferred hyperlactacidemia as the lone factor which significantly predicted cyanide poisoning at an odds of 73.0 (5.7-936.1). Moreover, blood cyanide level significantly correlated with the increase of blood lactate (p = 0.0033). CONCLUSIONS: This study supports the hypothesis lactic acidosis primarily results from the direct toxicity of cyanide.

Hemorrhagic infarct of basal ganglia in cardiac arrest. CT and MRI findings. 2 cases.

We report the CT and MRI findings in two cases of hemorrhagic infarct of the basal ganglia (BG), following out-of-hospital cardiac arrest (CA). In case 1, Brain-CT realized at day 2 showed bilateral and almost symmetric hemorrhagic infarct of the BG and infarct of the tectum of the mesencephalon. In case 2, MRI realized at day 6 showed hemorrhagic infarct of both lenticular nuclei on T2 GE images. In both cases there was no medical history and the cardiovascular and the coagulation profile were normal. In these cases, the lesions are observed earlier than reported in a few previous radiological cases. Similar lesions have been reported in pathological studies. These lesions seem occur early after CA. Reperfusion is probably responsible for the hemorrhagic transformation. The reason why some patients present either BG or brainstem infarct or both remains unclear. Bilateral and symmetric hemorrhagic infarct of the BG, especially of the Lenticular nuclei, and infarct of the dorsal pons and mesencephalic tegmentum seem to be a characteristic feature of profound and prolonged hypotension or of CA.

Extracorporeal Cardiopulmonary Resuscitation (ECPR) in the Prehospital Setting: An Illustrative Case of ECPR Performed in the Louvre Museum.

INTRODUCTION: Extracorporeal Cardiopulmonary Resuscitation (ECPR) is now considered for the treatment of refractory cardiac arrest. CASE REPORT: In an urban city like Paris, extraction times of in-hospital ECPR can be long for patients presenting with refractory cardiac arrest. Using the medicalized prehospital system, we developed a possible early prehospital ECPR implementation. This case report is an example of ECPR prehospital implementation in the Louvre Museum. CONCLUSION: Patients eligible for ECPR must be selected according to strict criteria. Further research is necessary to compare prehospital and in-hospital implementation.

Endovascular Versus External Targeted Temperature Management for Patients With Out-of-Hospital Cardiac Arrest: A Randomized, Controlled Study.

BACKGROUND: Targeted temperature management is recommended after out-of-hospital cardiac arrest. Whether advanced internal cooling is superior to basic external cooling remains unknown. The aim of this multicenter, controlled trial was to evaluate the benefit of endovascular versus basic surface cooling. METHODS AND RESULTS: Inclusion criteria were the following: age of 18 to 79 years, out-of-hospital cardiac arrest related to a presumed cardiac cause, time to return of spontaneous circulation <60 minutes, delay between return of spontaneous circulation and inclusion <240 minutes, and unconscious patient after return of spontaneous circulation and before the start of cooling. Exclusion criteria were terminal disease, pregnancy, known coagulopathy, uncontrolled bleeding, temperature on admission <30°C, in-hospital cardiac arrest, immediate need for extracorporeal life support or hemodialysis. Patients were randomized between 2 cooling strategies: endovascular femoral devices (Icy catheter, Coolgard, Zoll, formerly Alsius; n=203) or basic external cooling using fans, a homemade tent, and ice packs (n=197). The primary end point, that is, favorable outcome evaluated by survival without major neurological damage (Cerebral Performance Categories 1-2) at day 28, was not significantly different between groups (odds ratio, 1.41; 95% confidence interval, 0.93-2.16; P=0.107). Improvement in favorable outcome at day 90 in favor of the endovascular group did not reach significance (odds ratio, 1.51; 95% confidence interval, 0.96-2.35; P=0.07). Time to target temperature (33°C) was significantly shorter and target hypothermia was more strictly maintained in the endovascular than in the surface group (P<0.001). Minor side effects directly related to the cooling method were observed more frequently in the endovascular group (P=0.009). CONCLUSION: Despite better hypothermia induction and maintenance, endovascular cooling was not significantly superior to basic external cooling in terms of favorable outcome. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00392639.

Out-of-hospital cardiac arrest from brain cause: epidemiology, clinical features, and outcome in a multicenter cohort*.

OBJECTIVES: Although sudden cardiac death has been broadly studied, little is known on cerebrovascular events revealed by out-of-hospital cardiac arrest. We aimed to describe clinical features and prognosis of these patients and identify characteristics that could suggest a cerebrovascular etiology of the out-of-hospital cardiac arrest. DESIGN: Retrospective review (1999-2012) of databases of three regional referral ICU centers for out-of-hospital cardiac arrest. SETTING: Patients admitted to ICU for management of successfully resuscitated out-of-hospital cardiac arrest. PATIENTS: Patients were included when subarachnoid hemorrhage, intracranial hemorrhage, ischemic stroke, sub/epidural hematoma, or cerebral thrombophlebitis was identified as the primary cause of out-of-hospital cardiac arrest. Traumatic or infectious causes were excluded. Patients were compared with a group of out-of-hospital cardiac arrest of nonneurological origin. INTERVENTIONS: All medical records of the three prospective ICU databases, registered according to the Utstein style, were reviewed. MEASUREMENTS AND MAIN RESULTS: Among 3,710 patients admitted for out-of-hospital cardiac arrest, 86 were included (mainly subarachnoid hemorrhage, n = 73). Prodromes were mostly neurological but falsely evoked a cardiac origin in six patients. Electrocardiogram displayed abnormalities in 64% of patients, with 23% of pseudoischemic pattern (ST-segment elevation or left bundle branch block). Mortality rate was 100%, with brain death as the leading cause. In comparison with the nonneurological out-of-hospital cardiac arrest group, female gender, onset of neurological prodromes, lack of other prodromes, initial nonshockable rhythm, and unspecific electrocardiogram repolarization abnormalities were independent predictive factors of a primary cerebrovascular etiology. When present, the combination of these elements displayed an area under the receiver operating characteristic curve of 0.86 (95% CI, 0.81-0.91). CONCLUSIONS: Presentation of cerebrovascular event complicated with out-of-hospital cardiac arrest may mimic coronary etiology, but several clinical elements may help to identify brain causes. Even if survival is null, the high proportion of brain deaths provides opportunity for organ donation.

Influence of α-stat and pH-stat blood gas management strategies on cerebral blood flow and oxygenation in patients treated with therapeutic hypothermia after out-of-hospital cardiac arrest: a crossover study.

OBJECTIVES: In patients treated with therapeutic hypothermia after out-of-hospital cardiac arrest, two blood gas management strategies are used regarding the PaCO2 target: α-stat or pH-stat. We aimed to compare the effects of these strategies on cerebral blood flow and oxygenation. DESIGN: Prospective observational single-center crossover study. SETTING: ICU of University hospital. PATIENTS: Twenty-one therapeutic hypothermia-treated patients after out-of-hospital cardiac arrest more than 18 years old without history of cerebrovascular disease were included. INTERVENTIONS: Cerebral perfusion and oxygenation variables were compared in α-stat (PaCO2 measured at 37 °C) versus pH-stat (PaCO2 measured at 32-34 °C), both strategies maintaining physiological PaCO2 values: 4.8-5.6 kPa (36-42 torr). MEASUREMENTS AND MAIN RESULTS: Bilateral transcranial middle cerebral artery flow velocities using Doppler and jugular vein oxygen saturation were measured in both strategies 18 hours (14-23 hr) after the return of spontaneous circulation. Pulsatility and resistance indexes and cerebral oxygen extraction were calculated. Data are expressed as median (interquartile range 25-75) in α-stat versus pH-stat. No differences were found in temperature, arterial blood pressure, and oxygenation between α-stat and pH-stat. Significant differences were found in minute ventilation (p = 0.006), temperature-corrected PaCO2 (4.4 kPa [4.1-4.6 kPa] vs. 5.1 kPa [5.0-5.3 kPa], p = 0.0001), and temperature-uncorrected PaCO2 (p = 0.0001). No differences were found in cerebral blood velocities and pulsatility and resistance indexes in the overall population. Significant differences were found in jugular vein oxygen saturation (83.2% [79.2-87.6%] vs. 86.7% [83.2-88.2%], p = 0.009) and cerebral oxygen extraction (15% [11-20%] vs. 12% [10-16%], p = 0.01), respectively. In survivors, diastolic blood velocities were 25 cm/s (19-30 cm/s) versus 29 cm/s (23-35 cm/s) (p = 0.004), pulsatility index was 1.10 (0.97-1.18) versus 0.94 (0.89-1.05) (p = 0.027), jugular vein oxygen saturation was 79.2 (71.1-81.8) versus 83.3% (76.6-87.8) (p = 0.033), respectively. However, similar results were not found in nonsurvivors. CONCLUSIONS: In therapeutic hypothermia-treated patients after out-of-hospital cardiac arrest at physiological PaCO2, α-stat strategy increases jugular vein blood desaturation and cerebral oxygen extraction compared with pH-stat strategy and decreases cerebral blood flow velocities in survivors.

Vitamin K1 antagonisation is not safe in high thromboembolic risk patients with over-anticoagulation.

We report a case of a fatal massive anterior acute myocardial infarction (AMI) after administration of vitamin K1 for over-anticoagulation following cardioembolism from mechanical mitroaortic valve prostheses associated with atrial fibrillation.

Vancomycin Sequestration in ST Filters: An In Vitro Study.

BACKGROUND: Sequestration of vancomycin in ST® filters used in continuous renal therapy is a pending question. Direct vancomycin-ST® interaction was assessed using the in vitro NeckEpur® technology. METHOD: ST150® filter and Prismaflex dialyzer, Baxter-Gambro, were used. Two modes were assessed in duplicate: (i) continuous diafiltration (CDF): 4 L/h, (ii) continuous dialysis (CD): 2.5 L/h post-filtration. RESULTS: The mean initial vancomycin concentration in the central compartment (CC) was 51.4 +/- 5.0 mg/L. The mean percentage eliminated from the CC over 6 h was 91 +/- 4%. The mean clearances from the CC by CDF and CD were 2.8 and 1.9 L/h, respectively. The mean clearances assessed using cumulative effluents were 4.4 and 2.2 L/h, respectively. The mean percentages of the initial dose eliminated in the effluents from the CC by CDF and CD were 114 and 108% with no detectable sequestration of vancomycin in both modes of elimination. DISCUSSION: Significant sequestration adds a clearance to that provided by CDF and CD. The study provides multiple evidence from the CC, the filter, and the effluents of the lack of an increase in total clearance in comparison with the flow rates without significant sequestration in the ST® filter comparing cumulative effluents to the initial dose in the CC. CONCLUSIONS: There is no evidence ST® filters directly sequestrate vancomycin.

Caspofungin sequestration in a polyacrylonitrile-derived filter: Increasing the dose does not mitigate sequestration.

OBJECTIVES: Critically ill patients frequently require continuous renal replacement therapy. Echinocandins are recommended as first-line treatment of candidemia. Preliminary results suggested echinocandin sequestration in a polyacrylonitrile filter. The present study aimed to determine whether increasing the dose might balance sequestration. METHODS: An STX filter (Baxter-Gambro) was used. A liquid chromatography-mass spectrometry method was used for dosage of caspofungin. In vitro drug disposition was evaluated by NeckEpur (Neckepur, Versailles, France) technology using a crystalloid medium instead of diluted/reconstituted blood, focusing on the disposition of the unbound fraction of drugs. Two concentrations were assessed. RESULTS: At the low dose, the mean measured initial concentration in the central compartment (CC) was 5.1 ± 0.6 mg/L. One hundred percent of the initial amount was eliminated from the CC within the 6-h session. The mean total clearance from the CC was 9.6 ± 2.5 L/h. The mean percentages of elimination resulting from sequestration and diafiltration were 96.0 ± 5.0 and 4.0 ± 5.2%, respectively. At high dose, the mean measured initial concentration in the CC was 13.1 mg/L. One hundred percent of the initial amount was eliminated from the CC within the 6-h session. The mean total clearance from the CC was 9.5 L/h. The mean percentages of elimination resulting from sequestration and filtration were 88.5% and 11.5%, respectively. CONCLUSION: Increasing the dose does not mitigate caspofungin sequestration in the STX filter. The results raise caution about the simultaneous use of caspofungin and polyacrylonitrile-derived filters. Intermittent modes of renal replacement therapy might be considered. For sensitive species, fluconazole might be an alternative.

Elimination of cefotaxime using polysulfone and polyacrylonitrile-derived filters: An in vitro assessment.

Continuous renal replacement therapy (CCRT) efficiently eliminates cefotaxime. To our knowledge, there are no previous in vitro studies dealing with the disposition of cefotaxime. We studied the elimination of cefotaxime by two filters in a model mimicking a session of CRRT using the NeckEpur® technology. The ST150®-polyacrylonitrile filter with the Prismaflex, Baxter-Gambro, and the AV1000®-polysulfone filter with the Multifiltrate Pro, Fresenius, were studied. Continuous filtration used a flowrate of 1 L/h in post-dilution only. Simulated blood flowrate was set at 200 mL/min. Routes of elimination were assessed using the NeckEpur® technology. Cefotaxime concentrations were measured using ultra high-performance liquid chromatography, and tandem mass spectrometry. Two sessions were performed using the ST® filter and three using the AV® filter. Stability of cefotaxime during 6 h was assessed in triplicate with a mean variation of concentrations of 2.4 ± 1.5% at the end of the study. The mean measured initial concentration in the central compartment (CC) for the five sessions was 52.4 mg/L. The mean amount eliminated from the CC at the end of the sessions using the ST150®-polyacrylonitrile and the AV1000®-polysulfone filters were 72% and 73%, respectively. The clearances of cefotaxime from the central compartment (CC) were 1.1 and 1.2 L/h, respectively. The mean sieving coefficient were 0.99 and 0.99, respectively. The mean percentages of the amount eliminated from the CC by filtration/adsorption were 87/13% and 92/8%, respectively. Both adsorption percentages were below 15%. We conclude neither the ST150®-polyacrylonitrile nor the AV1000®-polysulfone filters result in clinically significant adsorption of cefotaxime.

Near-complete adaptation of the PRiMA knockout to the lack of central acetylcholinesterase.

Acetylcholinesterase (AChE) rapidly hydrolyzes acetylcholine. At the neuromuscular junction, AChE is mainly anchored in the extracellular matrix by the collagen Q, whereas in the brain, AChE is tethered by the proline-rich membrane anchor (PRiMA). The AChE-deficient mice, in which AChE has been deleted from all tissues, have severe handicaps. Surprisingly, PRiMA KO mice in which AChE is mostly eliminated from the brain show very few deficits. We now report that most of the changes observed in the brain of AChE-deficient mice, and in particular the high levels of ambient extracellular acetylcholine and the massive decrease of muscarinic receptors, are also observed in the brain of PRiMA KO. However, the two groups of mutants differ in their responses to AChE inhibitors. Since PRiMA-KO mice and AChE-deficient mice have similar low AChE concentrations in the brain but differ in the AChE content of the peripheral nervous system, these results suggest that peripheral nervous system AChE is a major target of AChE inhibitors, and that its absence in AChE- deficient mice is the main cause of the slow development and vulnerability of these mice. At the level of the brain, the adaptation to the absence of AChE is nearly complete.