The accuracy and precision of the Accutracker ambulatory blood pressure monitor

Prerequisite to the use of ambulatory blood pressure monitors in epidemiologic research is demonstration of a satisfactory level of accuracy and precision. Previous evaluations of these devices raise a number of methodological concerns which complicate interpretation of their findings. Also, important issues regarding the precision of blood pressure measurements and the identification of factors associated with measurement inaccuracies remain unaddressed. To assess the accuracy and precision of the Accutracker ambulatory blood pressure monitor, we obtained five serial estimates of resting blood pressure on 120 ambulatory subjects in The Johns Hopkins Medical Institutions in 1987. Two Accutrackers and two manual observers independently recorded blood pressure with the order determined at random. The fourth observer in each sequence obtained a replicate measurement. For both systolic and diastolic blood pressures, the mean difference between Accutracker and manual measurements was less than 3 mmHg for each pairwise comparison. Scatter plots and regression analyses demonstrated that both Accutrackers tended to underestimate high systolic and diastolic blood pressures. In bivariate and multivariate analyses, increased age was significantly associated with underestimation of systolic blood pressures by both Accutrackers. With respect to the precision of blood pressure measurement, no significant differences were present among the four observers. In summary, our data suggest that the Accutracker has satisfactory accuracy and precision, but that accuracy is not uniform across patient subgroups.

Elective versus therapeutic neck dissection in early carcinoma of the oral tongue

A prospective, randomized trial was carried out to assess the value of elective versus therapeutic neck dissection in early squamous cell carcinoma of the oral tongue. Disease-free survival (median follow-up 20 months) was 52 percent versus 63 percent in patients who underwent hemiglossectomy alone and those who underwent hemiglossectomy and radical neck dissection, respectively (difference not statistically significant). Patients with a tumor depth of less than 4 mm did significantly better than those with a tumor depth of greater than 4 mm; they were also more likely to have uninvolved nodes at elective radical neck dissection compared with those with a tumor depth of greater than 4 mm. However, when the survival rates of patients in the two treatment groups were compared with respect to a tumor depth of 4 mm, there was no significant difference between the hemiglossectomy and the hemiglossectomy and radical neck dissection groups. A policy of interval elective radical neck dissection only in those with a tumor depth of greater than 4 mm may optimize cure rates and avoid neck dissection in those unlikely to develop neck recurrence.

Delayed hemolytic transfusion reactions in sickle cell anemia

Delayed hemolytic transfusion reaction (DHTR) developed in three patients with sickle cell anemia seen over an 18-month period at Cook Country Hospital. The DHTR was associated with severe pain crisis, with spherocytic hemolytic anemia, a positive direct antiglobulin test result, previously undetected erythrocyte alloantibodies, and disappearance of Hb A on cellulose acetate electrophoresis. Delayed hemolytic transfusion reactions may be more common than is generally recognized and should be considered when a patient has a sickle cell pain crisis shortly after receiving a transfusion.

Prophylactic neck dissection in squamous cell carcinoma of oral tongue: a prospective randomized study

This paper presents the first report of an ongoing prospective randomised clinical trial in early T1T2N0 carcinoma of the oral tongue. The problems of regular follow-up in an indigent population from the vast rural expanse of India has been successfully overcome in this trial by close personal follow-up. The trial addresses itself specifically to prophylactic vs. therapeutic surgical management of the neck in T1T2N0 patients with cancer of the oral tongue. Overall disease, free survival (median follow-up 22 months) is higher (64% vs. 47%) in the group receiving prophylactic neck dissection. Disease-free survival for those with positive nodes at prophylactic neck dissection was twice that of those who underwent a subsequent therapeutic neck dissection (57% vs. 28%). Contralateral neck node metastasis has been identified as a significant factor in neck failures in those patients undergoing simultaneous prophylactic neck dissection.

Comparative analysis of glycosylated hemoglobins by ion-exchange column chromatography and high-performance liquid chromatography in patients with hemoglobinopathies

Cation-exchange chromatography gives falsely decreased values for glycosylated hemoglobins (GHbs) in patients with abnormal hemoglobins (Hbs) such as S, D, G, C, E, and O. This decrease is thought to be proportional to the percentage of abnormal Hb present. In the authors' study, cation-exchange column chromatographic GHb values on 84 nondiabetic patients heterozygous for Hb S, 28 AS diabetic patients, and 23 nondiabetic patients heterozygous for Hb C were calculated to account for the percentage of abnormal Hb, and the resulting values were compared with the GHb values obtained by high-performance liquid chromatography (HPLC). There existed a good correlation between the calculated GHb and the GHb obtained by HPLC (r = 0.92 for AS and r = 0.94 for AC). In patients with elevated Hb F, chromatographic GHb values are falsely high. In such cases, correction can be made by subtracting the Hb F value from the observed GHb. In laboratories where cation exchange chromatography is used, accurate determination of GHb can be made by adjusting observed values for portion of the abnormal Hb present.

Sports injuries as seen at an accident and emergency department

We present certain characteristics of 1,000 consecutive patients who attended an Accident and Emergency Department (A&E) with an injury sustained as a result of sport. The majority of injuries occurred as a result of football. Sports injuries had a higher requirement of X-ray than general trauma patients. A minority were treated at the site of injury. A fifth of patients required no treatment or a simple dressing. Commonest treatment was a support bandage. Only 2% required immediate in-patient treatment. Those affected by sports injuries tend to be young and of working age and may lose work time as a result of their injuries and therefore appropriate treatment is justified.

Sports injuries' postal survey: difficulties encountered in assessment of outcome

We present the results of a postal survey on the outcome of sports injuries treated in an Accident and Emergency Department which shows that this is unsuitable for assessing their outcome. There are, however, some points of interest relating to associated morbidity and satisfaction with treatment in the Accident and Emergency Department.

Five years' experience of bacteraemia in sickle-cell anaemia

In a review of all adults admitted with sickle-cell anaemia to Cook County Hospital between January 1980 and April 1985, 15 instances of bacteraemia were identified. In these patients, bacteraemia was characterised by slow onset, an identifiable focus of infection and lack of hypotension or abnormal coagulation of the blood. The organisms, most often isolated were Escherichia coli and Salmonella species. Two patients died, both with Salmonella enteritidis bacteraemia. Neither death could be attributed to the acute effects of infection. The outcome of bacteraemia in adults with sickle-cell anaemia appears to be more favourable than that in children.

Pulmonary edema associated with subarachnoid hemorrhage. Evidence for a cardiogenic origin

A 56-year-old woman with no history of cardiac disease developed acute pulmonary edema following a subarachnoid hemorrhage. A constellation of findings, including elevated creatine kinase MB isoenzyme activity in the absence of electrocardiographic or scintigraphic evidence of acute myocardial infarction, elevated pulmonary artery wedge pressure, segmental wall motion abnormalities, and depressed ejection fraction of the left ventricle demonstrated by two-dimensional echocardiography and radionuclear ventriculography, pointed to a direct myocardial injury leading to cardiac failure. The evidence for cardiogenic origin of pulmonary edema provided by this case is in contrast to the belief that "neurogenic" pulmonary edema is of noncardiac origin.

Iron stores in adults with sickle cell anemia

Iron status was investigated in 60 adults with sickle cell anemia as determined by stainable iron in bone marrow aspirates, serum ferritin, serum iron, and the total iron-binding capacity. Seventeen patients (28%) were found to have absent bone marrow iron. There was an excellent inverse correlation between serum ferritin and the serum transferrin (p less than 0.001), and a significant positive correlation between serum ferritin and transferrin saturation (p less than 0.005), bone marrow iron (p less than (p less than 0.001), and history of prior blood transfusion (p = 0.005). Results of complete radiologic examination of the gastrointestinal tract and proctoscopy were negative in the 17 patients in the iron-deficient group. The high incidence of iron deficiency may be related to excessive urinary losses of iron. Our data indicate that serum ferritin values of less than 30 ng/ml are diagnostic of iron deficiency in patients with sickle cell anemia, with a high degree of specificity (98.7%). However the sensitivity of the test at a serum ferritin level of 30 ng/ml is only 32%. The diagnostic evaluation and the management of sickle cell anemia in iron-deficient patients needs to be better defined.

Serum ferritin and sequestered stores of body iron

A 47-year-old man with sickle cell anemia, chronic cor pulmonale, and congestive heart failure died following a short illness. A diagnosis of iron deficiency was established during life by usually accepted criteria including a low serum ferritin concentration. Autopsy showed no stainable iron in the bone marrow, liver, and the heart. Marked deposits of iron were seen in the kidneys and the atrophic spleen. These findings suggest that the serum ferritin concentration may not reflect the metabolically sequestered stores of iron in the spleen and the kidneys.

Infection with parvovirus-like virus and aplastic crisis in chronic hemolytic anemia

From 1980 to 1982 seven adults with chronic hemolytic anemia were admitted to Cook County Hospital, Chicago, with aplastic crisis. Six of these patients had sickle cell anemia, the seventh patient had beta thalassemia intermedia. Virologic studies showed that six patients had acute infection with the human parvovirus-like virus; in the remaining patient the lack of appropriate specimens precluded viral diagnosis. We describe the features of the virus infection and accompanying erythroid aplasia, and discuss the role of parvovirus-like virus as the etiologic agent in the arrest of erythrocyte production.

Iron deficiency and sickle cell anemia

In a patient with sickle cell anemia, iron deficiency was accompanied by hypochromic, microcytic RBCs, absence of bone marrow iron, and a low serum ferritin level. The mean corpuscular hemoglobin concentration (MCHC) was decreased (27.6 g/dL) and was associated with an extreme scarcity of sickled erythrocytes in blood smears. Iron therapy resulted in reticulocytosis and an increase in sickled erythrocytes. In vitro studies demonstrated a decrease in sickling of erythrocytes as a function of oxygen saturation of the blood when the patient was iron deficient. The whole blood oxygen dissociation curve showed a substantial decrease in oxygen pressure necessary to produce 50% saturation of hemoglobin at pH 7.4 and 37 degrees C (P50), indicating an increased oxygen affinity. These data suggest that a reduction of the MCHC induced by iron deficiency may ameliorate sickling.

Intravascular aggregation after acute intracranial hypertension by epidural balloon compression in cats

The authors have studied the effect of acute intracranial hypertension produced by placement of an epidural balloon (control group) in cats, on cerebral perfusion, evoked responses, and hematological parameters. These elements were measured in similarly injured animals which underwent isovolemic hemodilution with dextran 75, after relief of intracranial hypertension. Four hours after balloon deflation, perfusion was markedly impaired in 30% of the control group, and was reduced to 11% in the dextran-infused group. The suppressed N1 amplitude of somatosensory evoked responses on the compression side, the reduced platelet aggregability, and the erythrocyte-deformability by intracranial hypertension were all significantly more restored in the dextran-infused group after decompression. The percentage of platelets with volumes between 21.75 and 48.75 cu mu (normal 9.75 to 12.75 cu mu) significantly increased after decompression. Activation of platelets during intracranial hypertension leads to an increase in platelet volume from platelet aggregation, and correlates with a decrease in platelet aggregability. It was also suggested that reduction of erythrocyte deformability was not caused by erythrocyte aggregation. The authors emphasize the role of intravascular factors such as vascular obstruction by platelet aggregates, and difficulty in passage of erythrocytes through capillaries due to reduced deformability, in the disturbance of the microcirculation following acute intracranial hypertension. The protective effect of dextran 75 by inhibition of platelets as well as hemodilution is stressed.

Erythrocyte survival in patients with porcine xenograft aortic and mitral valves

Ten patients with porcine xenograft aortic and mitral valve prostheses were studied three to 36 months (mean 15 months) postoperatively for evidence of hemolysis. Studies included complete blood count, reticulocyte count, red cell indices, percentage of schistocytes on blood smears, bilirubin concentration, lactic dehydrogenase, serum iron, total iron binding capacity, haptoglobin, serum folate and vitamin B12 levels, Coombs' test, methemoglobin reduction test, autologous 51Cr erythrocyte survival, and urinary examination for iron and hemosiderin. All patients were hemodynamically stable. Nine patients had normal valve function and no evidence of hemolysis. One patient with paravalvular aortic regurgitation had mechanical hemolytic anemia with a negative Coombs' test. Porcine valve xenografts do not seem to be associated with hemolysis unless complicated by a paravalvular leak.

The pedestrian problem: a 12-month review of pedestrian accidents

Three hundred and sixty-one pedestrians involved in road accidents in the course of a year have been studied. Fourteen of the pedestrians died following hospital admission, and analysis of data from Strathclyde Police showed that another 16 pedestrians died at the roadside. Certain characteristics of the whole group are reviewed and a plea is made for more appropriate use of available statistics in the production of practical road safety legislation.

Road traffic accident related morbidity as seen in an accident and emergency department

This paper describes some of the findings of a prospective study of victims of road traffic accidents arriving at the Western Infirmary's Accident and Emergency Department over a period of 12 months. More than half the accidents occurred during leisure hours thus likely to stretch the resource of the hospital services. More than a third of the total number of patients were young male drivers. Serious injuries were significantly more often sustained among pedestrians who were often older. Victims of motor-cycle accidents less often escaped serious injuries. Blood ethanol studies on a small sample suggested that male pedestrians were often highly intoxicated. A public health education programme is regarded as a primary measure in preventing a large proportion of serious morbidity and mortality especially amongst pedestrians.

Edwardsiella tarda osteomyelitis in a patient with SC hemoglobinopathy

Edwardsiella tarda is a recently identified gram-negative organism of the family Enterobacteriaceae. Reports of human infections with E tarda have been infrequent. We review 14 cases of systemic edwardsiellosis reported in the literature and report a case of E tarda osteomyelitis in a patient with sickle cell-hemoglobin C disease. In our case the remains of a snake may have been the source of the organism. Systemic edwardsiellosis is rare, and it may present as meningitis, endocarditis, bacteremia, liver abscess, or osteomyelitis. In 12 of 15 cases reported, systemic E tarda infection occurred in patients suffering from additional debilitating illnesses.

Bilateral pulmonary 67Ga uptake in a patient with a benign monoclonal gammopathy

Bilateral pulmonary uptake in an asymptomatic patient with normal chest X-rays and a monoclonal gammopathy is described. At the 11-month follow-up the patient is asymptomatic and chest X-ray remains normal.