Medullary metastasis causing impairment of respiratory pressure output with intact respiratory rhythm.

We present an unusual case of weaning failure. A 67-yr-old man presented with confusion, hyponatremia, and hypercapnic respiratory failure that necessitated mechanical ventilation. CXR revealed a right hilar mass (non-small-cell carcinoma on biopsy). Level of consciousness improved with treatment of his hyponatremia. However, attempts at weaning were complicated by hypercapnia with no overt distress. Resistance and elastance were only slightly abnormal, excluding mechanics as a cause of respiratory failure. Maximal inspiratory pressure (MIP) and vital capacity (VC) were reduced at -15 cm H2O and 0.97 L, respectively. Limb muscle strength was well preserved, suggesting isolated respiratory muscle weakness. During a weaning trial respiratory rate increased from 7 to 40 breaths/min as PCO2 increased from 56 to 89 mm Hg, confirming an intact respiratory pacemaker and good response to CO2. However, spontaneous Pdi was only 1 to 2 cm H2O (< 20% of Pdimax) despite profound hypercapnia. The fact that the patient did not utilize a greater fraction of his pressure-generating capacity suggested preferential impairment of the automatic respiratory centers. MRI showed a large central metastatic lesion in the rostral medulla with only a thin rim of uninvolved tissue. This case illustrates the utility of relating the magnitude of spontaneous efforts to maximal voluntary efforts as a means of localizing the site of involvement in cases of respiratory muscle weakness. It also demonstrates that a large medullary mass lesion may selectively impair brainstem modulation of respiratory pressure output while sparing other medullary functions, and in particular the pacemaking function of the respiratory centers.

Neuropsychiatric systemic lupus erythematosus and the syndrome of inappropriate secretion of antidiuretic hormone: a case report with very late onset systemic lupus erythematosus.

The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) associated with neuropsychiatric lupus (NP-SLE) is rare. We report a case of SIADH associated with the new onset of SLE in an 88-yr-old female. The unique features of this case include the extreme age of onset of SLE presenting with neuropsychiatric manifestations and positive antiribosomal P antibody titres. Both the NP manifestations of SLE and SIADH were highly correlated with the SLE disease activity. This case illustrates a novel presentation of NP-SLE with SIADH which may develop due to antibody-mediated hypothalamic dysfunction.

Intracranial gas: a pictorial essay.

Intracranial gas is a common finding on postcraniotomy computed tomography scans. It can also be found in a wide variety of other benign and life-threatening clinical settings. Because intracranial gas is never normal, its presence must be explained. This pictorial essay describes the imaging features of intracranial gas and demonstrates the findings for many of the causes of this condition.

A choroid plexus papilloma arising from an incidental pineal cyst.

We report a case of an incidental pineal cyst discovered on MR imaging that progressed to a choroid plexus papilloma. The MR features of pineal cysts, the difficulty of distinguishing benign cysts from cystic neoplasms, and the implications for surgical management are discussed.

Interhospital transfer of the critically ill trauma patient: the potential role of a specialist transport team in a trauma system.

A specialist transfer team based in the regional intensive therapy unit (ITU) at the Western Infirmary, Glasgow, acts as a central interhospital retrieval team for Glasgow and the west of Scotland. The establishment of trauma systems has been proposed. This paper describes the activities of the specialist transfer team to illustrate the potential role of a central retrieval team within such a system.

Heterotopic ossification in children after iliopsoas release.

Heterotopic calcification or ossification of the soft tissues adjacent to the lesser trochanter was observed in the radiographs of 4 patients during a retrospective review of the records of 68 patients with Perthes' disease. This abnormality has since been seen in one other patient with Perthes' disease and in five with spastic quadriplegia. All 10 patients are known to have undergone iliopsoas release as part of adductor tenotomy. The authors believe that the heterotopic ossification is related to the surgery.

Myoclonic epilepsy--pitfalls in diagnosis and management.

Three cases of myoclonic epilepsy presenting in adolescence are described. Seizures were uninfluenced by treatment with carbamazepine. Substitution of sodium valproate in early adult life resulted in all becoming seizure-free. A high degree of clinical awareness is required in making the correct diagnosis and in choosing appropriate therapy for this form of epilepsy which can present with generalised tonic-clonic or partial seizures.