Biomedical subjects
Publications and source records attributed to J Freeman.
We report a case of corrosive burns to the mouth, oesophagus and trachea in a three-year-old boy who ingested potassium permanganate crystals. The pathophysiology and treatment options are discussed. The prevention of accidental ingestion could be improved with careful packaging of the solid tablet or crystalline forms.
The case reports of two children with obstructive lesions of the larynx are presented to illustrate the advantages of transtracheal ventilation for paediatric endoscopic laser surgery. The first patient was a four-month-old infant with inspiratory stridor due to a subglottic haemangioma obstructing 80 per cent of the lumen. The second patient was a five-year-old child with posterior synechiae of the larynx. The anaesthetic and ventilation techniques were the same for both cases. A transtracheal catheter was introduced percutaneously into the trachea under endoscopic control and connected to a high frequency jet ventilator. The advantages of this technique during laser surgery are: clear vision of the operative field, good gas exchange, elimination of airway trauma from intubation, reduction of the hazard of airway fires, and decreased risk of aspiration of blood and debris. In addition, this method of providing oxygen and/or mechanical ventilation may be extended into the postoperative period. In certain situations, this technique can be an attractive alternative to a tracheostomy with its potentially dangerous and incapacitating complications in infants and small children.
Gamma-glutamyl transpeptidase (GGT) activity has been shown to increase in preneoplastic cells in various experimental carcinogenesis models and in some human tumors. This pilot study was undertaken to examine its potential use in detection of sites of human oral carcinogenesis. Samples were taken from 16 surgical specimens: 12 resection specimens for squamous carcinomas and 4 benign mucosal lesions. Twelve of the patients were tobacco users. Diffuse GGT activity was found in all tobacco users and heavy cellular activity in all carcinomas. In four of the carcinoma-resection specimens, occasional cells staining heavily for GGT activity were noted in epithelium distant from the tumor itself. These results are discussed in relation to the potential value of GGT activity as a marker from preneoplastic changes in oral epithelium.
The mean lengths of stay and discharge rates per 10,000 patients were compared for Victoria, Australia, and the United States on a DRG-specific basis to explain variations in hospital bed utilization and costs. Results were presented for a number of high-volume DRGs where the differences between the two hospital systems were substantial. For several DRGs associated with chronically ill patients, the mean lengths of stay were much longer in Victoria, although most of the difference disappeared after the removal of outliers. The presence of many acute-care patients in Victoria in several DRGs associated with minor surgical procedures produced very low mean lengths of stay. In the United States, rates were markedly higher for providing several major elective surgical procedures and very high-volume medical DRGs. The results of this comparison indicate that greater control over admission and discharge practices could promote greater efficiency and higher quality care in both Australia and the United States.
Most information in hospital epidemiology comes from observational studies of hospitalized patients rather than planned experiments, and in such observational studies the characteristics of study patients may vary widely, even within a single hospital. Any comparison between hospital populations will usually contain additional, unintended contrasts among patients with varying degrees of health. Adult patients, for example, may have vastly different underlying diseases, and infants may be of substantially different birth weights. We used both underlying disease and birth weight as indices of the basic severity of illness in order to adjust for confounding by differences in underlying disease in reanalyses of several published studies. We give an example in which differing birth weights among groups of infants compared artifactually double the apparent effect of nosocomial infections as a cause of mortality, and another example in which differing degrees of severity of underlying illness artifactually halve the apparent effect of appropriate antibiotics in preventing death from bacteremia with gram-negative bacilli. We describe simple intuitive methods based on stratification, adapted from chronic disease epidemiology, to remove confounding effects during analyses.
We report the case of a patient who developed severe hypoxemia and an unusual arrhythmia, accelerated idioventricular rhythm, during flexible fiberoptic bronchoscopy. Coronary artery disease was subsequently suspected despite an unremarkable history and physical examination, and confirmed by a thallium 201 imaging. The appearance of accelerated idioventricular rhythm during fiberoptic bronchoscopy should raise the possibility of underlying coronary artery disease.
We describe a patient with chronic hypernatraemia (plasma sodium 148-155 mmol/l) and partial nephrogenic diabetes insipidus who had received prolonged lithium treatment. Despite stopping the drug for one year the abnormalities remained. Infusion of hypertonic saline (NaCl 855 mmol/l) allowed the characterization of osmoregulation of thirst and vasopressin secretion. Linear regression analysis of plasma vasopressin and osmolality defined the function, pAVP = 0.27 (pOsm - 301), and analysis of thirst measured by a visual analogue scale and plasma osmolality, the function, thirst = 0.16 (pOsm - 302) where pAVP and pOsm represent plasma arginine vasopressin and osmolality respectively. The slopes of the regression lines which describe the sensitivity of the osmoreceptors were within the normal range, but both abscissal intercepts, which define the thresholds for vasopressin release and thirst, were markedly elevated in comparison to normal (upper limit less than 290 mOsm/kg). Other investigations of electrolytes, anterior pituitary function and high definition computed tomographic scanning of hypothalamo-pituitary region were all normal. We conclude that this patient's chronic hypernatraemia was due to resetting of the osmostats for both vasopressin release and thirst, a rarely described mechanism to account for hypernatraemia. Although it is probable that the partial nephrogenic diabetes insipidus was related to prolonged lithium therapy, the cause of the reset osmostats remains unclear.
Miscellaneous cardiac abnormalities can occur after electrical burns. The long term outcomes are still unknown. We studied 10 patients, 9 of whom suffered high-voltage electrocution, and one of whom was struck by lightning. Serial electrocardiograms (ECG) and serum MB creatine phosphokinase isoenzyme (MB-CPK) activities were obtained during their stay in hospital. ECG and thallium 201 cardiac scintigraphy at rest, as well as echocardiograms were obtained in all patients 4 to 48 months after discharge. In hospital, 9 patients showed one or more abnormal findings at physical examination (4 cases), ECG (8 cases), MB-CPK (1 case). At long term follow-up, 5 patients had one or more myocardial functions or conduction abnormalities, with or without symptoms. One patient had compensated heart failure. Nine patients were asymptomatic. Abnormal ECG findings persisted in 3 patients. Three cardiac scans showed evidence of regional myocardial hypoperfusion. Decreases in left ventricular indices measured by echocardiogram were found in 3 patients. We conclude that high-voltage electrocution is associated with a high incidence of cardiac abnormalities, which may persist. Long term evaluation, requiring cardiac T1 201 scintigraphy and echocardiogram, may be justified.
Antinucleolar antibodies are of interest in 2 important areas, namely, autoimmune diseases and specific products involved in the "mitogenic cascade." The former have delineated a series of novel nuclear and nucleolar elements including the recently described proliferating cell nuclear antigens (PCNA), some of which are present in the nucleolus only at specific times in the G1-S phase of the cell cycle. Important new proteins such as "fibrillarin" (34 kD/pI 8.5) and a 125 kD nucleotide containing protein have been identified with antinucleolar antibodies. Protein p145 is a nucleolar PCNA that is present in growing and dividing cells but not in normal resting tissues. Antinucleolar antibodies offer powerful tools, not only for identification of specific nucleolar proteins important in the cell cycle, but also for purification of their genes and analysis of mechanisms of gene control that operate the "time windows" of the cell cycle.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Cardiac contusion is frequently seen after blunt chest trauma; it is often missed, and can cause serious complications. The incidence, features and outcome of cardiac contusion are described.
Vinzolidine (VZL), a new semisynthetic vinca alkaloid, was studied by using 3H-labeled VZL administered PO in four patients. At single doses from 1.5 to 36.5 mg/m2 (0.034-0.919 mg/kg) radioactivity was rapidly absorbed with a half-life of absorption of 1 h and a peak at 4 h. Plasma decay of radiolabel followed a biphasic pattern with an alpha half-life of 10.48 h and a beta half-life of 172 h. The apparent plasma clearance was dose-dependent. The total radiolabel recovered was 52.9% +/- 11.4% of the administered label, with 90% in the feces. HPLC analysis revealed that in all extracted plasma, urine, and feces the predominant material was unchanged VZL. Several metabolites were observed but not identified.
A case is reported of a 23 year old white man who was struck by lightning. The patient suffered cardiac and respiratory arrest. Immediately, he received external cardiac massage and artificial breathing, which were successful. He was then admitted to an intensive care unit, where the diagnosis of acute myocardial infarction was made, on the basis of electrocardiographic abnormalities, a significative elevation of cardiac enzymes, and ultimately a thallium-201 scintigraphy. There were no complications of this heart injury, except for a persistent sinus tachycardia, which was treated by the infusion of a beta-blocking agent (oxprenolol). This case showed the importance of rapidly undertaking resuscitative measures in these circumstances, and to admit such a patient to an intensive care unit to undergo continuous cardiac monitoring, because the possibility of potentially serious cardiac complications, like life-threatening cardiac rhythm disturbances or acute myocardial infarction, as well as preventive, or curative, treatment of the complications which may follow lightning injury. This attitude is justified by the usually excellent prognosis of these patients.
The authors investigated how duration of disease and duration of risk until onset of disease relate prevalence odds ratios and cumulative incidence ratios, respectively, to incidence density ratios in a steady-state population. Using information on durations, they demonstrated how incidence density ratios may be estimated from the information available in variants of the case-referent study and their cohort study analogues. The standard case-referent study involves an incidence series of cases and a prevalence series of noncases. One variant is a study of a prevalence series of cases and a prevalence series of noncases. Another variant involves comparison of two incidence series for sequential incident events. Factors associated with disease risk have been termed risk indicators, and, by analogy, factors associated with disease duration are defined as duration indicators. These duration indicators may be identified through the study of duration ratios. Ratios of durations in steady-state populations may be combined with the prevalence and cumulative incidence information available in the variants of the standard study designs to obtain estimates of incidence density ratios.
Congenital cystic dilatation of the biliary tree (Caroli's disease) is a rare condition that usually presents with ascending cholangitis. This report demonstrates the difficulty of recognizing other complications of Caroli's disease antemortem. A 35-year-old man developed a subphrenic abscess and malignant transformation of the biliary tree; both were clinically undetected. Episodes of pain, pyrexia, or weight loss should be assessed carefully and the complications of Caroli's disease considered before attributing such symptoms to recurrent cholangitis.
In an attempt to define why the joint synovial cavity is prone to develop persistent synovial inflammation we show that hypoxia is induced by pressure changes caused by exercise in the presence of an inflammatory effusion. On resting 'reperfusion injury' may take place. The biochemistry of reperfusion injury has only recently been defined and perhaps surprisingly for an insult that has hypoxia as its central ingredient involves the subsequent production of oxygen derived free radical species. We apply the reaction sequences that are believed to occur during hypoxic/reperfusion injury to the joint synovial cavity and, on the basis of reported 'in vivo' observations, suggest novel therapeutic approaches that we believe are applicable to the treatment of persistent synovial inflammation.