Is the leak test reproducible?

BACKGROUND: The leak test is an accepted practice for evaluating airway edema and patient readiness for extubation. Reproducibility and interobserver reliability for this test have not been established. We studied the reproducibility and reliability of the leak test in and among health care professionals. METHODS: Thirteen consecutive intubated patients were tested in triplicate and in blinded fashion by three observers to determine the leak around the endotracheal tube before extubation. All patients were pharmacologically paralyzed and sedated before assessment. RESULTS: Neither interobserver or intraobserver variability was statistically significant when a standardized method was used to determine the leak. CONCLUSION: The leak test is reliable by the same or different observers regardless of varied clinical experience when using a standardized approach to measuring the leak.     

Spontaneous pneumothorax: is it under tension?

A diagnosis of tension pneumothorax is usually only considered within the context of trauma, incorrect chest drain insertion or positive pressure ventilation. Four patients are presented who developed spontaneous tension pneumothorax with no precipitating factors. In three of these instances, the diagnosis was only made radiologically and in every case the treating physician was unaware that a spontaneous tension pneumothorax could occur. Previously, emphasis has been placed on tracheal deviation in a tension pneumothorax. However, this is an inconsistent finding as one of the cases highlights. Patients may appear surprisingly clinically well until they decompensate. These cases are highlighted to raise awareness of this potentially life threatening condition.     

Absorption and endogenous faecal excretion of calcium by low birthweight infants on feeds with varying contents of calcium and phosphate

Low birthweight infants aged 4-41 days were given from birth one of three experimental milk formulae varying widely in content of calcium and phosphate. Ca and P in feed, urine, and faeces were measured between carmine markers corresponding to a metabolic period of 48 hours. Calcium enriched in 46Ca to provide a marker for the dietary Ca was added to one feed and 46Ca measured in urine and faeces. True absorption of Ca and endogenous excretion into the bowel could then be inferred. True absorption of Ca was proportional to Ca intake and independent of P intake. Endogenous faecal excretion seemed to be independent of both Ca P intakes, and varied widely between different infants in the range 4-150 mg/day. Urine Ca was low and retention was essentially the difference between true absorption and endogenous faecal excretion. Retention of Ca tended to be much greater on a high Ca intake, but the variability in retention between infants on a given intake was large, paralleling the variability in endogenous faecal excretion. The variability in plasma Ca concentrations in newborn infants may in part be a consequence of wide individual variability in endogenous faecal excretion. The 46Ca marker technique provides a means of investigating the factors determining this variability.     

Prolonged QT interval and cardiac arrhythmias in two neonates: sudden infant death syndrome in one case

Two neonates with arrhythmias and the long QT syndrome are described. The arrhythmias were detected in utero and both infants were apparently well after birth. The first infant, although well, had a bradycardia for the first 9 days of life. A normal heart rate was documented at 10 days but a prolonged QT interval was not appreciated on the ECG. He was discharged from hospital but died suddenly and unexpectedly 3 days later. A post-mortem examination failed to find a cause for his death which therefore fell into the category of the sudden infant death syndrome (SIDS). A retrospective analysis of the perinatal electrocardiogram showed a probable junctional rhythm with 2:1 conduction to the ventricle; the QT interval was prolonged at 0.52 seconds (QTC = 0.63). The second infant had a QT interval of 0.52 seconds (QTC = 0.54) and frequent ventricular premature beats on a 24-hour electrocardiogram. She was treated with propranolol and remains well 2 years later. Sudden infant death has often been described in the siblings of children with the long QT syndrome and one other report described a case of SIDS which was said to have had a prolonged QT interval on the perinatal ECG. This report, however, provides unquestionable evidence, in one case, of an association between the long QT syndrome and SIDS.     

Urinary tract infection in infants and children evaluated by ultrasound

Fifty-nine pediatric patients with urinary tract infection (UTI) underwent renal ultrasonography, excretory urography, and voiding cystourethrography. The imaging procedures were analyzed retrospectively to determine their relative effectiveness in detecting abnormalities that might predispose the patient to UTI. Voiding cystourethrography provided valuable information, particularly the presence or absence of vesicoureteral reflux, that could not be obtained from the other procedures. Excretory urography was less specific than ultrasonography in the majority of patients, with the exception of those who had renal scarring. The authors recommended ultrasonography as the initial imaging procedure in the evaluation of children with UTI. When the sonogram is normal, excretory urography is not considered necessary, but voiding cystourethrography is thought to be essential. If sonography is abnormal, excretory urography and/or other follow-up studies are indicated.     

Molecular breakpoint analysis and relevance of variable mosaicism in a woman with short stature,primary amenorrhea,unilateral gonadoblastoma,and a 46,X,del(Y)(q11)/45,X karyotype

Congenital hydrocephalus associated with aqueductal stenosis and/or agenesis of the corpus callosum has been described in newborn males with mutations in L1CAM, a gene that encodes a neural cell adhesion molecule. These males usually have severe mental retardation and may have spastic paraplegia and adducted thumbs. In contrast, Hirschsprung disease, or absence of ganglion cells in the distal gut, has rarely been described in such individuals. We report a male infant who had severe hydrocephalus identified in the prenatal period with evidence of aqueductal stenosis and adducted thumbs at birth. He developed chronic constipation, and rectal biopsy confirmed the diagnosis of Hirschsprung disease. Molecular testing of the L1CAM gene revealed a G2254A mutation, resulting in a V752M amino acid substitution. A common polymorphism in RET, but no mutation, was identified. Our patient represents the third example of coincident hydrocephalus and Hirschsprung disease in an individual with an identified L1CAM mutation. We hypothesize that L1CAM‐mediated cell adhesion may be important for the ability of ganglion cell precursors to populate the gut, and that L1CAM may modify the effects of a Hirschsprung disease–associated gene to cause intestinal aganglionosis. © 2002 Wiley‐Liss, Inc.     

Granulomatous mastitis: a report of seven cases

The clinical history and histological features of seven cases of granulomatous mastitis are presented. The lesion occurs in young parous women as a tender extra-areolar breast lump. Histologically, non-caseating discrete granulomas are present, confined to breast lobules with, in three cases, coalescence of the granulomas and microabscess formation. Pathogenesis of the changes is discussed. It is thought that granulomatous mastitis is an entity morphologically distinct from duct ectasia/plasma cell mastitis and the commoner forms of granulomatous breast diseases.     

Integrity of cholinergic innervation to the lower esophageal sphincter in achalasia

The human lower esophageal sphincter (LES) is believed to be innervated by nonadrenergic, noncholinergic inhibitory nerves, and cholinergic excitatory nerves. In idiopathic achalasia, LES relaxation is abnormal because the inhibitory nerves to the sphincter are either absent or functionally impaired. The integrity of cholinergic excitatory nerves to the LES, however, has not been thoroughly evaluated. In 27 patients with untreated idiopathic achalasia, and 21 healthy volunteers, we investigated the hypothesis that postganglionic cholinergic nerves to the LES are functionally intact in achalasia. The LES responses to atropine, edrophonium, methacholine, amyl nitrite, and pentagastrin were assessed. In 2 achalasia patients, patterns of fasting motor activity in the LES were investigated during overnight manometric studies. Resting LES pressure was significantly greater in the achalasia patients, 41 +/- 4 mmHg (mean +/- SE), than in the normal subjects, 20 +/- 2 mmHg. Atropine significantly reduced LES pressure in both groups by 30%-75%. Edrophonium increased LES pressure in the achalasia patients but had negligible effect on the normal subjects. The LES in achalasia patients exhibited an increased sensitivity to both methacholine and pentagastrin compared with the normal subjects. In both patients who underwent an overnight manometric study, the LES exhibited cyclic phasic contractile activity synchronous with gastric contractions during the migrating motor complex. We conclude that the study findings support the hypothesis that postganglionic cholinergic LES innervation in achalasia patients is either normal or only minimally impaired, in contrast to the marked impairment of the inhibitory nerves governing LES relaxation.