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Objectives: To propose the different modalities of management of the allergic risk occurring during paediatric anaesthesia., Study Design: Literature analysis., Methods: Literature research using the Medline((R)) database and MeSH format according to keywords, including publications in French and English since 1982., Results: The overall incidence for anaphylactic reactions was estimated at one in 7741 anaesthetic procedures during paediatric anaesthesia. Latex anaphylaxis was mostly involved with an incidence at one in 10,159 anesthetic procedures. The risk factors of latex sensitization are known. Primary latex prophylaxis is efficient in patients at risk of latex sensitization. In contrast to adults, neuromuscular blocking agents (NMBAs) are rarely involved in children, with an incidence at 1 in 81,275 anaesthetic procedures. The Ring and Messmer clinical scale allows quantifying the severity and helps managing the care of immediate hypersensitivity reactions. Clinical symptoms associate cardiovascular, respiratory and cutaneous-mucous signs according to different severity grades. Epinephrine associated to fluid loading, remains the first-line agent in case of severe reactions. The allergological assessment is key to the management of these reactions and is required in order to identify the mechanism of the reaction and the culprit drug or substance involved., Conclusions: Allergic reactions to NMBAs occurring during paediatric anaesthesia are rare whereas those with latex are more frequent. Therefore, the reduction of the allergic risk during paediatric anaesthesia essentially requires a latex-free environment., (Copyright (c) 2009 Elsevier Masson SAS. All rights reserved.)

We report the case of a severe acute asthma, which required, after optimal medical therapy, helium and sevoflurane CO-administration after tracheal intubation. The Anesthetic Conserving Device allowed sevoflurane use with intensive care unit's ventilator. The helium-sevoflurane association was maintained during 9 days to decrease the bronchospasm, waiting for the efficiency of an aetiologic treatment. We discuss the suitability of this association to treat severe acute asthma, and its administration modalities.

Unlabelled: HIGH PREVALENCE: Several epidemiological studies have shown that the prevalence of bronchial asthma is high in the elderly. It is often difficult to establish the diagnosis of asthma in this population because of the scarcity of symptoms. Pulmonary function tests are widely used to confirm the diagnosis. These tests are possible in most elderly people excepting cases of severe dementia., Mechanisms: Pathophysiology of asthma in the elderly may be characterized by superimposition of different factors: 1) the effect of age which is associated with airway adrenoreceptor dysfunction; 2) the impact of chronic pulmonary diseases which may increase airways inflammation; 3) the role of triggers such as infections or various medications., Management: Management of asthma consists in a specific treatment of trigger(s) associated with anti-inflammatory and bronchodilator medications. Elderly subjects may have difficulty using offinhalators and spacer devices are widely used.

The practice of medicine, in the United States, is regulated by different concepts when compared to France. Anti-asthmatic medications are very similar to the ones available in Western Europe, except the combinations (e.g. Berodual/Duovent), and the 200 mcg Beclomethasone MDls. Environmental control is emphasized, as well as a smoke-free environment. Immunotherapy is not recommended, although actively prescribed for generating income. For the last few years, American and French concepts -and problems-regarding asthma are coming closer.

The anticholinergic compounds are potent bronchodilators. We will not consider atropine, which is no longer used, but its congener, ipratropium, less prone to side effects. This agent acts by blocking muscarinic receptors. It has a complementary role to other bronchodilators such as beta-agonists and theophylline. In stable asthmatic patients, it may be that ipratropium is less potent than beta-adrenergic agents. In patients with chronic bronchitis and emphysema, it is a potent bronchodilator. Although the place of ipratropium is still discussed in acute asthma and COPD, this agent adds significantly to the level and duration of bronchodilatation by its combination with other bronchodilators.

The authors report their observation of a serious allergic incident involving the blue patent, hospitalisation in their intensive care unit, and extremely major therapy. They describe the three mechanisms of allergic reaction: real anaphylaxia, and anaphylactoid reaction, either by direct histamino-release, or by alternate activation of the complementary system. It would seem that, after doses of the differing fractions of complement in this patient, there was an activation of the complementary system. The authors emphasize the importance of preventive treatment: hypo-histamine, antihistamine, corticoid, and curative relative to the gravity of the disorders observed: cutaneous, cardiac, and respiratory. Finally, they recall that this test must be carried out in a hospital establishment with a reanimation unit.

The hyperreactivity-modulating effect of SCH 1000 and fenoterol was tested in two groups of 10 patients. The drugs were administered at random, in simple blind fashion. Baseline pulmonary function was in the range of predicted values for all patients. One group received 80 micrograms of SCH 1000. When the drug was inhaled after carbachol challenge, pulmonary function returned to normal values in all patients. When the drug was inhaled before challenge, a shift to the right of the dose-effect curves was observed in all patients but 1. The other group received 800 micrograms of fenoterol. When the drug was administered after carbachol challenge, all 10 patients returned to baseline within 10 min. When it was given before carbachol challenge, a shift to the right of the dose-effect curves was observed in 9 patients out of 10. SCH 1000 and fenoterol induced an effective protection against carbachol, increasing the PD20 and shifting the dose-effect curves to the right in most of the asthmatics. In 2 patients, 80 micrograms of SCH 1000 or 800 micrograms of fenoterol seemed too low in order to achieve a complete protective effect.

Forty-two patients were treated with beclomethasone dipropionate in doses of 400 microgram daily for no longer than three months. There were three main indications : attempt to withdraw corticosteroids or sympathomimetics ; treatment prior to desensitization ; treatment of asthma with severe permanent dyspnea. In 8 patients, systemic steroids of sympathomimetic drugs could be withdrawn. Dosage could be reduced by 50% or more in 21 cases, and by less than 50% in 9 cases. There were 3 failures, and results were unassessable in one case. No major side-effects were observed.

The use of anti-inflammatory corticoids in anesthesia and resuscitation is a long-standing fact, but their indications, owing to the risks to which they expose certain patients and owing to the uncertitude concerning their mechanism of action, are still badly defined. If certain indications (attacks of asthma, laryngeal oedema, certain peri-lesional oedemas) are considered as being categorial, the usefulness of anti-inflammatory corticotherapy is being more and more and more debated in other pathological conditions : infectious or chemical pneumonias, drowning, shocked lung, post-traumatic neuro-surgical conditions, cirrhosis. Very useful in precise indications, anti-inflammatory corticoids should not be prescribed, particularly in fragile patients whom we well know in resuscitation, without having weighed up the advantages and disadvantages related to this remarkable therapeutic instrument.

Protective and curative effects of parenterally administered bamifylline and theophylline on bronchospasm induced by standardized house dust inhalation were studied in two series of eight patients with allergic asthma to house dust. Preventive effects were assessed by variations in liminal allergen dose (LAD) required to double resistance of the air passages (Rap), measured by barometric body plethysmography after determining basal LAD levels. Thirty minutes afer a slow i.v. injection of bamifylline, and LAD mean value reached 920 +/- 950 % of control value, and was still at 830 +/- 1 000 % after 60 minutes. After theophylline, mean LAD values were 750 +/- 980 % at 30 minutes and 700 +/- 970 % at 60 minutes, a non-significant difference. Curative activity was evaluated by studying changes in Rap after the provocative inhalation test with house dust, the test being immediately followed by the administration of either bamifylline or theophylline. Similar results were also obtained employing this test : reduction in Rap of 35 +/- 17 % for bamifylline and 48 +/- 13 % for theophylline (non-significant difference) after 30 minutes, and of 38 +/- 25 % for bamifylline and 48 +/- 14 % for theophylline (non-significant difference) after 60 minutes. These findings suggest that these two xanthine derivatives possess comparable protective and curative effects against bronchospasm induced by allergen inhalation.

Three serious cases of status asthmaticus with severe hypercapnic acidosis unresponsive to adequate conventional therapy were treated by halothane. The efficiency of this treatment was assessed by the clinical state of the patient, the blood gases and the changes in peak airway pressure. Two patients improved dramatically in less than 24 h. No signs of cardiac toxicity of this drug were noted in spite of acid-base disturbances. These three cases showed the beneficial effect of halothane's-beta 2 stimulation in the treatment of status asthmaticus.

Oxytropium bromide, a new synthetic anticholinergic agent, delivered by a dose inhaler, was compared to a placebo in a cross-over double-blind trial. The drop in FEV1 after administration of increasing doses of acetylcholine aerosol spray was measured 45 min after administration of the test drug, and the dose-response curve was determined. The placebo modified neither acetylcholine threshold dose (bronchial sensitivity) nor the slope of the curve (bronchial reactivity). Oxytropium bromide elevated the response threshold and decreased bronchial reactivity to vagal stimuli.

In a patient under general anesthesia, the occurrence of bronchospasm can be readily treated provided the cause is diagnosed early. The corrective drugs to dilate are readily available: atropine, epinephrine and theophylline. In the choice of preanesthetics, anesthetics and adjuvants, it is important to remember that there are differences in the bronchomotor effects; most curareform drugs constrict except pancuronium; most inhalational anesthetics dilate in contrast to intravenous anesthetics. In the event that bronchospasm cannot be re relieved by drugs, intubation and assisted breating can be applied to maintain adequate gas exchange in the alveoli.