Bacteremic hemophilus influenzae pneumonia in adults. A report of 24 cases and a review of the literature.

Twenty-four cases of Hemophilus influenzae pneumonia diagnosed by positive blood or pleural fluid cultures are compared to 43 cases previously reported in the literatrue. Frequently associated illnesses in both series include alcoholism, chronic airways obstruction and preceding respiratory tract infection. Moderate temperature elevation and slight leukocytosis were common on admission in both groups. Chest roentgenograms in our series revealed both bronchopneumonia (75 per cent) and lobar consolidation (38 per cent). Pleural disease occurred frequently, with two empyemas noted on admission and nine additional effusions developing during therapy. Treatment of choice was ampicillin. All five patients who did not receive ampicillin died, whereas 16 to 19 who received this drug survived. High mortality (33 per cent) in our series may be attributed to the advanced age of the patients and the presence of associated illnesses. In addition, a 10 year review suggests a true increase in the incidence of H. influenzae pneumonia in adults.

Addition of anticholinergic solution prolongs bronchodilator effect of beta 2 agonists in patients with chronic obstructive pulmonary disease.

A randomized, double-blind placebo-controlled clinical trial was designed to assess the safety, efficacy, and duration of the bronchodilation resulting from the addition of 500 micrograms of ipratropium bromide (Atrovent; Boehringer Ingelheim, CT) inhalation solution to standard small volume nebulizer treatments with 2.5 mg albuterol inhalation solution. A total of 195 patients (63% men, average age 64 years) with > 10 pack-year smoking histories and stable, moderate-to- severe chronic obstructive pulmonary disease (COPD; forced expiratory volume in 1 second [FEV1] 1.02 liter, 38.8% predicted) from eight university-affiliated chest clinics in seven U.S. cities were enrolled into the study. Asthma, rhinitis, and eosinophilia were exclusions, as was daily use of > 10 mg of prednisone (or 20 mg on alternate days). There was a 2-week stabilization period during which the patients were instructed in the use of the small volume nebulizers, which they used three times daily with albuterol alone. They were asked to keep daily logs of peak flow rates, pulmonary symptoms, and additional medication usage. On their test day 1 the subjects came to the pulmonary function laboratory having been off theophylline for 24 hours and beta 2-agonists for 12 hours and performed a baseline spirometry. They then received their morning small volume nebulizer treatment of albuterol to which was added either 500 micrograms if ipratropium bromide or a saline placebo. Spirometry was repeated at 15, 30, and 60 minutes, and then hourly for 8 hours. Subjects then took home a 2-week supply of albuterol and test drug for thrice daily use in their small volume nebulizer. They were evaluated for pulmonary symptoms and adverse effects every 14 days. The 8-hour spirometry was repeated on test day 43 and finally on test day 85. Primary data evaluated were the peak increase in FEV1 and the area between the FEV1 baseline value and the 8-hour FEV1 curve. Similar calculations were made for forced vital capacity (FVC) and 25-75% forced expiratory flow (FEF25-75%). On test day 1 the peak increase in FEV1 for the ipratropium bromide + albuterol subjects was 26% greater than those on placebo + albuterol (p < 0.003). The area under the 8-hour FEV1 curve was 64% greater in those given ipratropium bromide on test day 1 (p < 0.0002). Similar increases were seen in FVC and FEF25-75%. The peak improvements in FEV1 and FVC with the addition of ipratropium bromide to albuterol were maintained on test days 43 and 85. Considering the safety and efficacy profiles of this combination, the data would suggest that ipratropium bromide inhalation solution should be considered first-line therapy for those patients with COPD requiring small volume nebulizer treatments.

Causes of cine image quality deterioration in cardiac catheterization laboratories.

Deterioration of cineangiographic image quality can result from malfunctions or technical errors at a number of points along the cine imaging chain: generator and automatic brightness control, x-ray tube, x-ray beam geometry, image intensifier, optics, cine camera, cine film, film processing, and cine projector. Such malfunctions or errors can result in loss of image contrast, loss of spatial resolution, improper control of film optical density (brightness), or some combination thereof. While the electronic and photographic technology involved is complex, physicians who perform cardiac catheterization should be conversant with the problems and what can be done to solve them. Catheterization laboratory personnel have control over a number of factors that directly affect image quality, including radiation dose rate per cine frame, kilovoltage or pulse width (depending on type of automatic brightness control), cine run time, selection of small or large focal spot, proper object-intensifier distance and beam collimation, aperture of the cine camera lens, selection of cine film, processing temperature, processing immersion time, and selection of developer.

Usefulness of transstenotic coronary pressure gradient measurements during diagnostic catheterization.

A difficult problem in coronary arteriography is the assessment of the hemodynamic significance of stenoses that appear angiographically to be of only moderate severity (25 to 75% diameter narrowing). This is particularly important in patients who may be candidates for invasive therapy, such as percutaneous transluminal coronary angioplasty (PTCA) or coronary bypass surgery. To determine the significance of such lesions, we measured transstenotic coronary pressure gradients in 15 patients with angiographically moderate stenoses. For comparison, similar measurements were made in 17 patients with severe stenoses (more than 75% diameter narrowing) being considered for PTCA. The transstenotic pressure gradients were measured with a 2.0Fr polyvinyl chloride catheter cleared of microbubbles of air by flushing with carbon dioxide and degassed saline solution and attached to a low-volume displacement transducer for optimal frequency response. Mean transstenotic pressure gradients greater than 10 mm Hg at rest or more than 20 mm Hg under conditions of high coronary blood flow, as induced by Renografin 76, appeared to be associated with objective evidence of myocardial ischemia and symptomatic relief from PTCA. Smaller pressure gradients occurred in patients whose symptoms probably were not ischemic in nature. Transstenotic pressure gradient determination performed at the time of diagnostic catheterization may provide assistance in clinical decision-making in selected patients with angiographically moderate stenoses.

Cardiopulmonary hemodynamics during sleep in subjects with chronic obstructive pulmonary disease. The effect of short- and long-term oxygen.

Some patients with chronic obstructive pulmonary disease (COPD) experience transient arterial hypoxemia (TAH) during rapid eye movement (REM) sleep. To examine the effect of short- and long-term low flow oxygen on TAH associated cardiopulmonary hemodynamics, we recorded pulmonary artery pressure (Ppa) and cardiac output during nocturnal sleep in seven male subjects with COPD. In all of the subjects, parameters were measured breathing room air at baseline time and after eight or more weeks of home supplemental oxygen (15 hours per day, 3 L/min). Five were also studied one full night at baseline time while breathing 3 L/min nasal oxygen. While breathing room air both before and after chronic home oxygen therapy, transient increases in Ppa during TAH were due to increased pulmonary vascular resistance in seven instances, increased cardiac output in four, and increases in both vascular resistance and cardiac output in two. Short-term supplemental oxygen lowered mean sleeping Ppa and eliminated TAH along with its associated hemodynamic changes in four of the five subjects; the fifth did not experience REM sleep. In the six subjects who complied with the eight-week home oxygen protocol, mean sleeping Ppa was significantly reduced (p less than 0.05). In four of these, total pulmonary resistance was lower and cardiac output higher after home oxygen therapy. Short-term supplemental oxygen is useful in correcting REM-associated TAH and in some hypoxemic subjects, reducing mean sleeping Ppa. Sustained reductions in pulmonary vascular resistance after long-term home oxygen therapy may be indicative of improved cardiac and pulmonary vascular status even in subjects showing minimal or no reduction in mean sleeping Ppa.

Pleural fluid pH in parapneumonic effusions.

The pH and carbon dioxide tension were measured in 24 consecutive parapneumonic effusions, along with the leukocyte count, leukocytic differential count, and levels of glucose and protein. Three categories of parapneumonic effusions were characterized: (1) empyemas; (2) benign (nonloculated) effusions; and (3) loculated effusions. A pH greater than 7.30 was present in all ten benign effusions, and spontaneous resolution occurred in each case. All ten empyemas and the four loculated effusions had a pH less than 7.30. All four loculated effusions required drainage with a chest tube for resolution. The pH of the pleural fluid alone separated the empyemas and loculated effusions from benign effusions. The early separation of parapneumonic effusions on the basis of the pleural fluid appears useful. If the pH is greater than 7.30, a benign effusion is present, and spontaneous resolution is likely. If the pH is less than 7.30, loculation of the pleural space may occur regardless of whether the effusion fulfills the criteria for empyema.

A computer program for calculation and interpretation of pulmonary function studies.

A computer program to calculate and interpret the standard pulmonary function tests has been developed on a programmable calculator system. The program computes both predicted and measured values for static and dynamic lung volumes, airways resistance and diffusing capacity. It then checks for differences between predicted and obtained values and interprets them according to a specific, clinically useful set of diagnostic criteria. By acquisition of a reliable and easy-to-use data processing system, a pulmonary function laboratory can significantly increase the efficiency and accuracy of its day-to-day work.

Comparison of the beta 1 and beta 2 adrenoceptor blocking properties of acebutolol and propranolol.

The purposes of this study were to evaluate the beta 1 and beta 2 adrenoceptor blocking properties of acebutolol and propranolol and measure the plasma levels of acebutolol, its acetylated metabolite and propranolol. Ten patients with reversible obstructive airways disease and hypertension received two separate dose levels of acebutolol and propranolol for five days each. Cardioselective properties were assessed by determining the beta 1 and beta 2 adrenergic-stimulating effects of terbutaline 5 mg before and at the end of each five-day treatment period. Both acebutolol and propranolol were clinically well tolerated. Following study drug there was a 100 percent inhibition of the beta 1 terbutaline effect, and an approximate 83 percent inhibition of the beta 2 terbutaline effect. There were no clinically significant differences between acebutolol and propranolol. The acetylated acebutolol metabolite accumulated levels two to three times higher than the parent compound, and its effects may have destroyed the cardioselectivity of acebutolol. Thus, acebutolol did not demonstrate clinically relevant cardioselectivity.

Reactive hyperemia as an indicator of peripheral vasodilation associated with arterial stenoses.

Reactive hyperemia occurs when an artery is temporarily occluded and the occlusion is then released. During a period of vascular occlusion, peripheral vascular dilatation develops distally, and is reversed only gradually after release of the occlusion. Reactive hyperemia was measured in the hind limbs of five mongrel dogs at different degrees of arterial stenosis to determine at what degree of stenosis compensatory vasodilatation of the peripheral vascular bed occurs. In the hind limbs of the dogs, which had been anesthetized, reactive hyperemia as an expression of peripheral vasodilatation did not occur until the critical stenosis (the stenosis at which resting flow started to drop) was reached. It began to occur only beyond the critical stenosis, and then increased as the vessel became totally occluded. This study contradicted the vasodilator reserve theory, which states that during progressive arterial stenosis the peripheral vascular bed dilates to maintain flow until the peripheral vascular bed is maximally dilated, when the critical stenosis is reached.

Variations in the blood supply of the left ventricular apex.

Contraction or perfusion abnormalities of the left ventricular apex are generally assumed to result from left anterior descending (LAD) artery disease since this vessel is the usual source of blood supply to this area of myocardium. Such an assumption may be erroneous since the left ventricular apex may be supplied by the LAD alone, both the LAD and posterior descending (PD) branch of the right coronary artery, or the PD alone. Blood supply of the left ventricular apex was prospectively studied angiographically in 431 adult patients. In 77.7%, the apex was totally supplied by the LAD. In 12.1%, the apex received dual blood supply from both the LAD and PD. In 10.2%, the LAD terminated well before the apex, which was totally supplied by the PD. With the latter two anatomic variations, the LAD tended to be shorter and smaller in caliber than usual, while the PD was longer and larger than usual. A short, narrow LAD therefore does not necessarily indicate coronary disease if the left ventricular apex is partially or completely supplied by the PD. Dysfunction or perfusion abnormalities of the apex do not necessarily indicate LAD disease.

Reactive hyperemia vs. pharmacologic hyperemia in the canine iliac circulation. A comparison.

Different methods of selective vasodilation have been described. One method is reactive hyperemia, which occurs when an arterial occlusion is released, and another method involves injection of vasodilator drugs. Since both arteriography and pressure measurements are often performed during hyperemia, it is important to know whether these two methods differ in the degree or duration of hyperemia achieved. We measured reactive hyperemia in the hind limb of five anesthetized mongrel dogs after arterial occlusion times between 20 seconds' and 20 minutes' duration and after selective intra-arterial injection of 5, 10, and 20 cc of Renografin-76. Only 5 cc of Renografin-76 created greater and longer lasting hyperemia than the maximum reactive hyperemia achieved after 10 minutes of arterial occlusion. For this reason, contrast material-induced hyperemia appears to be preferable to reactive hyperemia as an aid to peripheral arteriography and as an aid to the evaluation of aortoiliac stenoses.

Vascular resistance changes distal to progressive arterial stenosis: a critical re-evaluation of the concept of vasodilator reserve.

Previous studies have shown that with progressive arterial stenosis, resting blood flow does not start to diminish until 85-95% luminal area stenosis is reached. However, during hyperemic states, peak flow starts to diminish at only 40-60% stenosis. An autoregulatory mechanism has been postulated, whereby peripheral arterioles undergo compensatory vasodilatation, thereby maintaining resting flow. During hyperemia, some vasodilator reserve is presumably already used up, resulting in flow dropoff at an earlier stage. We measured flow and pressure and calculated peripheral vascular resistance (Rp) distal to progressive iliac artery stenoses in five dogs. Contrast injections proximal to the stenoses allowed precise angiographic quantitation of the lesions and provided reproducible hyperemic stimuli. Flow-stenosis relationships proved similar to those discussed above, but Rp distal to the lesions failed to show progressive decrease as stenosis increased. Thus, compensatory peripheral vasodilatation does not occur during most phases of progressive arterial stenosis. The contours of resting and hyperemic flow-stenosis curves are not related to the concept of vasodilator reserve but instead are readily explained by basic hydrodynamic principles.

Hemodynamic evaluation of arterial stenoses by computer simulation.

A new method to assess the hemodynamic severity of arterial stenoses was proposed and evaluated. It is based on a previously developed finite element computer simulation model for laminar-separated flow in arteries of axially varying cross-section; the present modification allows use of angiographic stenosis shapes acquired by automatic edge-detection algorithms. The method was validated by comparing its results with published experimental and theoretic results for ideal stenosis shapes. At moderate flowrates (Reynolds number = 500), poststenosis flow separation was predicted for moderately severe (75% area reduction) but not for mild (25%) stenoses. For high flowrates (Reynolds number = 900) in a severe stenosis (89%), stagnation and reversed flow were predicted and the experimental nondimensional pressure drop of 48.5 was correctly determined. Bernoulli's Equation, which neglects viscosity, predicted a drop of only 40. For a severe stenosis (89%), even at low Reynolds numbers (50), reversed flow agreeing with other theoretic solutions was predicted. Predictions are especially useful at low flow rates, where experiments are difficult to conduct. The height of the curve on the graph of nondimensional pressure gradient vs. Reynolds number reflects the hemodynamic severity of a particular stenosis; these curves were predicted for moderate and severe ideal stenoses and agree with experiments. A similar analysis is applied to an actual human coronary artery stenosis, and the results are demonstrated to have use in assessing interventions during angiography.

Anatomic variations of the coronary arteries supplying the anterolateral aspect of the left ventricle: possible explanation for the "Unexplained" anterior aneurysm.

Coronary arteriograms of 418 adult patients were studied to ascertain the frequency of variations in blood supply of the anterolateral free wall of the left ventricle; 92.6% had from one to three ramus medianus or diagonal branches supplying this area. Complete absence of any ramus medianus or diagonal branches was exceedingly rare (only 0.5% in this series), and when this occurs the angiographer should suspect complete occlusion of one or more such branches immediately at their origins. Failure to detect ostial occlusion of a ramus medianus or diagonal branch may be a cause of significant misinterpretation of coronary arteriograms.

Hemodynamic changes distal to selective arterial injections.

It has been assumed previously that the act of selectively injecting fluid through a catheter into an artery does not significantly alter hemodynamics in that vessel, provided open communication is maintained between the distal portion of the artery and the aortic lumen. In this study, blood flow was measured with an electromagnetic flow probe in distal branches of the left coronary or superior mesenteric arteries of 9 dogs while heparinized arterial blood was injected selectively into the parent vessels at varying rates up to 7 ml/sec. This resulted, in all experiments, in an abrupt and substantial rise in blood flow which was maintained for the duration of the injection. This phenomeon is due primarily to an increase in intraarterial pressure distal to the catheter tip, caused by the injection.

Pulmonary artery hypertension in chronic obstructive pulmonary disease: determination by chest radiography.

Pulmonary artery hypertension is a frequent complication of severe chronic obstructive pulmonary disease (COPD). A study was undertaken to determine whether analysis of the chest radiograph can reveal the presence of pulmonary artery hypertension in COPD. Sixty-one men with COPD (forced expiratory volume in 1 second 0.97 +/- 0.35 liters, mean +/- SD) underwent right heart catheterization, and in 46 the mean pulmonary artery pressure was elevated (greater than 20 mmHg). Plain chest radiographs of the 61 patients and 42 normal control subjects were evaluated. The right descending pulmonary artery (RDPA) was enlarged (greater than 16 mm) in 43 of 46 patients (93%) with an elevated mean pulmonary artery pressure, and the left descending pulmonary artery (LDPA) diameter also was enlarged (greater than 18 mm) in 43 of 46. Combined increased RDPA and increased LDPA diameter measurements permitted correct diagnosis in 45 of 46 patients (98%) with pulmonary artery hypertension, including all 26 a mild elevation of mean pulmonary artery pressure (21-30 mmHg). There was a significant correlation between pulmonary artery pressure and both RDPA and LDPA measurements. Analysis of RDPA and LDPA diameters on the plain chest radiograph is a sensitive and accurate method of detecting the presence and severity of pulmonary artery hypertension in COPD.

Prospectively gated cardiac CT. Preliminary results in normal and postinfarction animal models.

Cardiac motion introduces significant artifacts into standard CT images obtained through the heart. A newly developed prospectively gated CT system produced 87 gated scan sets in ten normal and infarcted dogs. Each cycle can provide up to 24 37-70 msec composite images of one transverse slice, equally spaced in time through the cardiac cycle. Eight to 12 2-second scans, obtained during a constant infusion of contrast, were required to collect the data for each gated set. The left and right ventricular myocardium was clearly seen, regions of myocardial infarction were identified, and atrial and ventricular filling and emptying were visualized. In areas of infarction, wall thickness was unchanged from diastole to systole. In addition to improved resolution, a gated CT series evaluation of wall motion abnormalities may provide a better means of locating myocardial infarction than the ungated CT image.

In vivo imaging and evaluation of platelet accumulation vs. time at arterial injury site.

The feasibility of quantitatively imaging platelet deposition over time following angioplasty of the abdominal aorta in a rabbit model, with and without antiplatelet treatment, was investigated. Ten male 3-4 kg rabbits were balloon de-endothelialized and placed on 2% cholesterol diet for eight weeks. Group A was untreated. In Group B, donors and recipients were treated with aspirin (5 mgm/kg) prior to and after angioplasty. Platelets were labelled with indium-111. Labelled platelets were injected just prior to PTA and images of 100,000 counts were obtained immediately and at 30 minutes, 1 hour, and 24 hours. In Group A, increased activity of angioplasty site vs. nonangioplastied aorta was seen immediately. This focal increase became more marked in hypercholesterolemic animals over the 24-hour period. In Group B, both hypercholesterolemic and normocholesterolemic, no focal uptake could be documented on sequential scans. This method and model are promising for in vivo evaluation of platelet-vessel wall interactions, in the setting of angioplasty and antiplatelet therapy.

Evaluation of optimized biplane pulmonary cineangiography.

Biplane pulmonary cineangiograms utilizing a short cine pulse width and automatic brightness control were performed in 47 patients during normal respiration. The diagnostic quality of the arteriograms was categorized as good in 33 patients, fair in 12 patients, and poor in two patients. Of the 18 patients in whom pulmonary emboli were identified, cineangiography displayed certain diagnostic features to advantage, including motion of emboli in ten and respiratory scissoring of vessels overcoming vascular superimposition in three. Optimized pulmonary cineangiography is an acceptable alternative to serial film pulmonary angiography for the diagnosis of pulmonary embolism.

Transcatheter embolotherapy for congenital renal arteriovenous malformations. Long-term follow-up.

Transcatheter embolization was performed five times in 3 patients with congenital renal arteriovenous malformations (AVM). The patients were followed for one to seven and a half years. Two patients whose AVM were completely occluded with Gelfoam have been asymptomatic with no evidence of hematuria. A third patient, embolized with Gelfoam and Ivalon without complete occlusion of the AVM, bled ten months after the first procedure, was re-embolized, and later had the AVM removed surgically. Superselective transcatheter embolization should be the initial treatment modality for congenital AVM with the aim to control bleeding and occlude those malformations supplied by the terminal portion of interlobar arteries. Large malformations supplied by multiple feeders may require operative ligation and removal of the AVM when vessels cannot be occluded satisfactorily because of massive shunting.