Sleep disordered breathing and its treatment in congestive heart failure.

Sleep disordered breathing (SDB) is a common problem with adverse cardiorespiratory, endocrinological, and endothelial effects. Recent studies demonstrate an even higher prevalence of SDB in congestive heart failure (CHF) than in a randomly selected population, with up to 40% and 11% having Cheyne Stokes respiration-central sleep apnoea and obstructive sleep apnoea-hypopnoea syndromes, respectively. Randomised controlled trials of nocturnal respiratory support for SDB associated with CHF for up to three months demonstrate significant benefits in terms of improvements in left ventricular ejection fraction, markers of sympathetic system activity, and quality of life. Further randomised controlled trials of larger scale and longer duration are required to establish the role and benefit of this intervention for the treatment of this debilitating condition. The evidence for the higher prevalence of SDB in CHF, its pathogenesis, its pathophysiological consequences, and the emerging benefits of respiratory support are reviewed.

Improvements in an oral aspirin challenge protocol for the diagnosis of aspirin hypersensitivity.

Oral aspirin challenge (OAC) is used to confirm aspirin hypersensitivity (AHs) but there is no consensus on a standardized protocol. As a prior clinical history of adverse reactions to aspirin is poorly predictive of a positive result from formal aspirin challenge, many patients have an OAC performed. We retrospectively identified and prospectively validated how a 1-day OAC protocol could be modified, and patient selection improved, to deliver a safe and more efficient service. In a retrospective audit of 45 OACs using a 2 h dose interval, all reactions occurred within 90 min of the threshold dose. Forty OACs were then performed using a 90-min dose interval. This reduced the mean duration of a positive and negative OAC from 6 to 5 h and from 8 to 6 h, respectively. Histories of multiple manifestations of AHs were found in 91.6% (11) of those with asthma, 87.5% (7) with angiooedema, 70.6% (12) with rhinosinusitis, 63.6% (7) with chronic non-vasculitic urticaria and all with anaphylaxis, who developed a positive OAC. None of those with anaphylaxis, 8.3% (1) with asthma and 12.5% (1) with angiooedema, with a positive OAC, had a history of a single manifestation of AHs. The efficiency of an OAC service can safely be improved by reduction of the dose interval from 2 to 1 (1/2) h, and more targeted patient selection, as the likelihood of a positive OAC increases among patients with a history of asthma, angiooedoema or anaphylaxis with multiple manifestations of AHs.

Multiple system atrophy presenting as central sleep apnoea.

A 61-yr-old male presented with apparent idiopathic central sleep apnoea but after 4 yrs developed features of autonomic, cerebellar and extrapyramidal dysfunction consistent with a diagnosis of multiple system atrophy (MSA). Though central sleep apnoea can occur in multiple sleep apnoea, it is less frequent than obstructive sleep apnoea and occurs in the later stages of the disease. The pathogenesis of MSA involves gliosis and neuronal cell loss in specific areas of the central nervous system. Central sleep apnoea in MSA may be due to the depletion of cholinergic neurons in the arcuate nucleus of the medulla by apoptosis. This is the first description of multiple system atrophy presenting as central sleep apnoea. The current authors believe that multiple system atrophy should be considered in the differential diagnosis of late onset central sleep apnoea and progressive hypoventilation.

Rocking bed and prolonged independence from nocturnal non-invasive ventilation in neurogenic respiratory failure associated with limb weakness.

A 40 year old mother of three with autosomal dominant scapuloperoneal muscular dystrophy presented with severe neurogenic respiratory failure requiring nocturnal non-invasive ventilation (NIV). Because of the development of profound proximal muscular weakness as a consequence of the progressive nature of her neurological disease, she eventually was unable to apply and remove the facial interface to set up her NIV circuit. She therefore became dependent on her children and carers to start and stop NIV during the night. A rocking bed was successfully employed as an alternative to nocturnal NIV. Ventilation was facilitated by the passive movement of the diaphragm as a consequence of the movement of the abdominal contents under the effect of gravity. Benefit was demonstrated objectively by pulse oximetry and subjectively by the improvement in the patient's symptomatology and continued independence at night. The ease of use of a rocking bed should be borne in mind when the necessity for nocturnal ventilatory support in neuromuscular disease results in the potential loss of independence for a patient.

G-CSF enables completion of tuberculosis therapy associated with iatrogenic neutropenia.

Neutropenia is a rare complication of anti-tuberculous therapy and is usually due to a single agent, most frequently isoniazid. The current case describes a previously healthy immunocompetent patient with tuberculosis of the lymph nodes who developed neutropenia due to a number of first line antibiotics (rifampicin, isoniazid and ethambutol) and streptomycin when introduced in combination and individually thus resulting in repeated treatment disruption. The introduction of twice-weekly subcutaneous granulocyte-colony stimulating factor to correct iatrogenic neutropenia facilitated the continuation and eventual completion of therapy without adverse effect. This is the first description of the use of granulocyte-colony stimulating factor to correct iatrogenic neutropenia due to anti-tuberculous antibiotics and the second description of the occurrence of iatrogenic neutropenia to more than anti-tuberculous antibiotic in an individual.