Herbert A. Saltzman

Complications and validity of pulmonary angiography in acute pulmonary embolism.

BackgroundThe Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) addressed the value of ventilation/perfusion scans in acute pulmonary embolism (PE). The present study evaluates the risks and diagnostic validity of pulmonary angiography in 1,111 patients who underwent angiography in PIOPED. Methods and ResultsComplications were death in five (0.5%), major nonfatal complications in nine (1%), and less significant or minor in 60 (5%). More fatal or major nonfatal complications occurred in patients from the medical intensive care unit than elsewhere: five of 122 (4%) versus nine of 989 (1%) (p<0.02). Pulmonary artery pressure, volume of contrast material, and presence of PE did not significantly affect the frequency of complications. Renal dysfunction, either major (requiring dialysis) or less severe, occurred in 13 of 1,111 (1%). Patients who developed renal dysfunction after angiography were older than those who did not have renal dysfunction: 74±13 years versus 57±17 years (p<0.001). Angiograms were nondiagnostic in 35 of 1,111 (3%), and studies were incomplete in 12 of 1,111 (1%), usually because of a complication. Surveillance after negative angiograms showed PE in four of 675 (0.6%). Angiograms, interpreted on the basis of consensus readings, resulted in an unchallenged diagnosis in 96%. ConclusionsThe risks of pulmonary angiography were sufficiently low to justify it as a diagnostic tool in the appropriate clinical setting. Clinical judgment is probably the most important consideration in the assessment of risk.

Clinical Characteristics of Patients with Acute Pulmonary Embolism

Abstract Among 117 patients with pulmonary embolism (PE) and no prior cardiac or pulmonary disease who participated in the National Heart, Lung, and Blood Institute Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study, combinations of clinical characteristics were identified that were present in nearly all in whom the diagnosis of PE was made. 1 We now assess these as well as additional combinations of characteristics in the entire population of patients with acute PE who participated in PIOPED, irrespective of the presence of prior cardiopulmonary disease.

Cardiovascular and blood gas responses to hyperbaric oxygenation

Abstract Ten normal subjects were studied while they breathed air and 100% oxygen at 1 and 3.04 atmospheres. Oxygen inhalation at 3.04 atmospheres was associated with a significant increase in arterial and venous pO 2 and O 2 content. Hemoglobin in the venous circulation was completely saturated in 8 of 10 subjects. Oxygen inhalation at 3.04 atmospheres produced a small but significant increase in venous pCO 2 , presumably due to the loss of the buffering effect of reduced hemoglobin. Heart rate and cardiac output fell significantly with little change in stroke volume during oxygen inhalation at 3.04 atmospheres, indicating that the decrease in cardiac output was rate-dependent. There was little change in mean arterial pressure but an increase in calculated peripheral resistance during oxygen inhalation at 3.04 atmospheres. Two subjects who demonstrated signs of acute oxygen intoxication did not differ significantly from the group as a whole either in terms of blood gas values or patterns of hemodynamic response.

Correlation of Clinical and Physiologic Manifestations of Sustained Hyperventilation

THE hyperventilation syndrome, as seen in anxious, tense persons, is characterized by paresthesia of the extremities and circumoral area, sensations of lightheadedness and altered consciousness and...

Diagnosis of acute pulmonary embolism in the elderly

The diagnostic features of acute pulmonary embolism among 72 patients greater than or equal to 70 years old were evaluated and compared with characteristics of pulmonary embolism among 144 patients 40 to 69 years and 44 patients less than 40 years old. Syndromes characterized by either 1) pleuritic pain or hemoptysis, 2) isolated dyspnea, or 3) circulatory collapse were observed with comparable frequency among patients greater than or equal to 70 years old and younger patients. One of these presenting syndromes occurred in 64 (89%) of the 72 patients greater than or equal to 70 years old. Those who did not show these syndromes were identified on the basis of unexpected radiographic abnormalities, which may have been accompanied by tachypnea or a history of thrombophlebitis. Among the 72 patients greater than or equal to 70 years with pulmonary embolism, dyspnea or tachypnea (respirations greater than or equal to 20/min) occurred in 66 (92%), dyspnea or tachypnea or pleuritic pain in 68 (94%) and dyspnea or tachypnea or radiographic evidence of atelectasis or a parenchymal abnormality in 72 (100%). Complications of angiography were evaluated among patients with and without pulmonary embolism. Major complications of pulmonary angiography among patients greater than or equal to 70 years old (2 [1%] of 200) were not more frequent than among younger patients (6 [1.1%] of 562) (p = NS). However, renal failure (major or minor) was more frequent in patients greater than or equal to 70 years old than in younger patients (6 [3%] of 200 versus 4 [0.7%] of 562) (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Usefulness of noninvasive diagnostic tools for diagnosis of acute pulmonary embolism in patients with a normal chest radiograph

The value of bedside examination and noninvasive tests in the diagnosis of acute pulmonary embolism (PE) among patients with a normal chest radiograph was investigated. Normal chest radiographs were present in 20 of 260 patients (8%) with acute PE and in 113 of 642 (18%) with suspected acute PE, in whom the diagnosis was excluded. A partial pressure of oxygen in arterial blood less than or equal to 70 mm Hg in a dyspneic patient with a normal chest radiograph was more often seen among patients with PE (9 of 17, 53%) than among patients in whom PE was excluded (18 of 93, 19%; p less than 0.01). However, no combinations of blood gases, signs and symptoms were strictly diagnostic. High probability ventilation/perfusion scans among patients with a normal chest radiograph were indicative of PE in only 6 of 9 patients (67%). Among patients with low-probability ventilation/perfusion scans, 8 of 47 (17%) had PE. This study showed that the combination of dyspnea and hypoxia in a patient with a normal chest radiograph is a useful clue to the diagnosis of PE. Although intuition suggested that ventilation/perfusion scans would yield better results in patients with a normal chest radiograph, the ability to diagnose PE by ventilation/perfusion scans in this subset of patients was not enhanced, except by a reduction of the percentage of patients with intermediate probability scans.

The Use of Hyperbaric Oxygenation in the Treatment of Cerebral Ischemia and Infarction

The therapeutic usefulness of hyperbaric oxygenation in cerebral vascular disease was evaluated in 22 persons with recent neurologic deficits caused by cerebral embolism, thrombosis, hemorrhage, or arteriographic complications. Hyperoxygenation produced a significant elevation in content and tension of oxygen in blood and increased the reservoir of oxygen available for utilization by neurons. Remarkable and dramatic improvement in neurologic function occurred in four patients. The improvement persisted in two patients. In two others the neurologic deficit recurred a few hours after removal from the hyperbaric chamber; repeated exposure to high oxygen pressures was associated with only temporary improvement. In six other patients there was some evidence of clinical recovery immediately after onset of hyperoxygenation, but the neurologic deficit returned during decompression. The remaining 12 patients did not improve during hyperbaric oxygenation.These observations indicate that in some patients neuronal structures remain viable for some hours after loss of function in acute cerebral ischemia. In such instances an increase in oxygen delivery may reverse cellular ischemia and prevent death of cerebral tissues. Hyperbaric oxygenation may provide supportive therapy in some patients with acute cerebral ischemia, thereby permitting the removal of the occlusive lesion by surgery or other methods.

Hyperbaric oxygenation in the treatment of acute myocardial infarction

Abstract The high mortality associated with shock and congestive failure during myocardial infarction has prompted new therapeutic approaches in patients with these complications. Because of the vital role of oxygen in maintaining myocardial function the application of hyperbaric oxygenation to patients with myocardial infarction has been suggested. Although it is possible to increase the amount of oxygen carried in blood to very high levels during hyperbaric oxygenation, there are many impediments to the effective use of this form of therapy. Studies utilizing a variety of animal models suggest that hyperbaric oxygenation may lower mortality from myocardial infarction. Although these studies are, at best, only slightly analogous to the events occurring during myocardial infarction in humans, they make further studies in humans reasonable. In the only human series of meaningful size there was no statistically significant difference in mortality between those treated with hyperbaric oxygenation and those who were not.

Migraine‐like phenomena after decompression from hyperbaric environment

THE VASCULAR mechanisms underlying the clinical symptomatology of migraine headaches are not completely understood. The classical picture of visual scintillations followed by a localized throbbing headache is thought to be caused by constriction of the posterior cerebral vessels with subsequent vasodilation of painsensitive intracranial or extracranial arteries. Migraine-like syndromes, however, have also been associated with other conditions such as vascular malformations’s2 and arteriographic procedures,3s4 suggesting that the vasomotor reactivity underlying the phenomena may be provoked by nonspecific mechanisms. The clinical characteristics of migraine have also been observed in decompression sickness in normal subjects.5.0 In such patients, the headache often appeared after descent from simulated altitudes of 30,000 to 38,000 ft. in a low-pressure chamber. The present report describes similar migraine-like illnesses after ascent from simulated depths of 66 to 135 ft. below sea level in a hyperbaric chamber. Scintillating scotomas and headaches, sometimes associated with paresthesia of the hand and focal electroencephalographic abnormalities, appeared in 4 young professional workers (1 nurse and 3 physicians), 3 of whom had a past history of vascular headaches of the migraine type. The clinical features of their disorder suggested attacks of migraine, hut their illnesses may have represented minor forms of decompression sickness. It is the purpose of this report to call attention to this phenomenon, which can be expected to appear more frequently in view of the greater use of hyperbaric chambers for medical purposes and the increasing extent of deep submergence activities.

Studies of Peripheral Circulation during Sickle-Cell Crisis

In 18 Negro patients with sickle-cell anemia or sickle cell-hemoglobin C disease, gradients of oxygen and pH were measured between brachial artery and superficial and deep venous system of the upper extremity. The results obtained during crisis were compared with those obtained from asymptomatic patients. Arterial oxygen unsaturation, with normal arteriovenous gradients for oxygen and pH was observed in the 11 asymptomatic patients. Unusually low arteriovenous gradients for oxygen and pH, mainly due to abnormal venous values, were found when blood draining from cutaneous areas was compared with arterial samples in the 7 patients studied during acute crisis. The 5 patients restudied after symptoms subsided showed a return toward normal of arteriovenous differences. The evidence suggests that during crisis arterialization of venous blood is the result of anatomic or functional by passes in the superficial circulation, so that oxygen is not removed by the tissues. It is postulated that a vascular neurogenic mechanism may be the precipitating factor in sickle-cell crisis. It is also suggested that a low arteriovenous oxygen gradient or arterialization of superficial vein blood may be used as a laboratory aid in establishing the diagnosis of sickle-cell crisis in uncertain cases.