Tuberculous enteritis and peritonitis. Report of 36 general hospital cases.

We studied 36 patients with gastrointestinal tuberculosis: 21 had peritonitis, 11 had enteritis, and four had both. Diagnostic criteria were (1) caseating granulomas or positive smear or culture from an abdominal specimen; (2) culture-proved pulmonary tuberculosis plus ascitic fluid containing protein, greater than 3.0 g/dL, and more than 50% lymphocytes, or granulomatous enterlitis on x-ray studies that resolved with antituberculous therapy. In only four of 15 patients with enteritis was the disease confined to the ileocecal region. Fourteen patients (40%) had complications: bowel obstruction in ten, perforation in six, and fistula in five. Five of these died. Two perforations and one death followed paracentesis and needle biopsy. Tuberculous peritonitis can be diagnosed without biopsy when lymphocytic exudative ascites responds to antituberculous chemotherapy given for concurrent culture-proved pulmonary tuberculosis. Patients with pulmonary tuberculosis and persistent abdominal complaints who have granulomatous enteritis should be considered to have tuberculous enteritis. Surgery is reserved for bowel obstruction, perforation, fistula, or a mass that does not resolve with drug therapy.

Persistent respiratory irregularity in patients with panic disorder.

BACKGROUND: Dysregulated respiratory control may play a role in the pathophysiology of panic disorder. This could be due to abnormalities in brain stem respiratory nuclei or to dysregulation at higher brain levels. Results from previous studies using the doxapram model of panic have yielded an unclear picture. A brief cognitive manipulation reduced doxapram-induced hyperventilation in patients, suggesting that higher level inputs can substantially alter their respiratory patterns. However, respiratory abnormalities persisted, including a striking irregularity in breathing patterns. METHODS: To directly study respiratory irregularity, breath-by-breath records of tidal volume (V(t)) and frequency (f) from previously studied subjects were obtained. Irregularity was quantified using von Neumann's statistic and calculation of "sigh" frequency in 16 patients and 16 matched control subjects. Half of each group received a standard introduction to the study and half received a cognitive intervention designed to reduce anxiety/distress responses to the doxapram injection. RESULTS: Patients had significantly greater V(t) irregularity relative to control subjects. Neither the cognitive intervention nor doxapram-induced hyperventilation produced significant changes in V(t) irregularity. The V(t) irregularity was attributable to a sighing pattern of breathing that was characteristic of panic patients but not control subjects. Patients also had somewhat elevated f irregularity relative to control subjects. CONCLUSIONS: The irregular breathing patterns in panic patients appear to be intrinsic and stable, uninfluenced by induced hyperventilation or cognitive manipulation. Further study of V(t) irregularity and sighs are warranted in efforts to localize dysregulated neural circuits in panic to brain stem or midbrain levels.

Use of ipratropium bromide in asthma. Results of a multi-clinic study.

A multi-center, double-blind, 90-day study compared an ipratropium bromide metered-dose inhaler (40 microgram four times a day) with a metaproterenol metered-dose inhaler (1,500 micrograms four times a day) in 164 patients with asthma; of the 144 patients who completed the study, 71 received ipratropium and 73 received metaproterenol. Our results suggest that both drugs were equally effective bronchodilators. Although the shape of the pulmonary function response curves suggested that ipratropium has different bronchodilator kinetics than metaproterenol (in that it has a slower onset of action and a more prolonged duration), comparison of the areas under the curves for the two drugs showed that there was no statistical difference between ipratropium or metaproterenol. The only significant side effects noted with ipratropium were cough and exacerbation of symptoms; no anticholinergic side effects were noted.

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.

Neuroendocrine responses to laboratory panic: cognitive intervention in the doxapram model.

Doxapram is a respiratory stimulant that appears to be a potent and specific panicogenic agent. It also elicits an abnormal ventilatory response in patients with panic. A replication study confirmed these findings and demonstrated that behavioral and ventilatory responses to doxapram were significantly modified by a psychological intervention designed to cognitively block panic. The replication study provided an opportunity to simultaneously investigate the neuroendocrine effects of the illness, the drug, the drug-induced panic attacks, and the cognitive intervention. Epinephrine (EPI), norepinephrine (NE), growth hormone (GH), adrenocorticotropin (ACTH), and cortisol were studied in patients with panic and control subjects given placebo and doxapram injections after receiving either standard instructions or a brief cognitive intervention. Patients with panic had elevated levels of EPI, ACTH, and cortisol throughout the study. Doxapram had little or no detectable effects on plasma NE, GH, ACTH, and cortisol. Doxapram-induced panic attacks were not associated with elevations in NE, GH, ACTH, or cortisol. Doxapram led to a rapid and very brief rise in plasma EPI, which was small in subjects who did not panic and pronounced in patients who did panic. The cognitive intervention attenuated the EPI response to doxapram, perhaps through its effect on panic, and modified the temporal pattern of ACTH and cortisol secretion. These results suggest that: (1) further study of catecholamine responses within the first few minutes after panic induction is needed; (2) intense panic can occur without significant activation of the hypothalamic-pituitary-adrenal axis; and (3) cognitive factors can modulate neuroendocrine activity in laboratory studies of patients with panic.

Safe intrahospital transport of critically ill ventilator-dependent patients.

STUDY OBJECTIVE: To determine whether manual ventilation during intrahospital transport of mechanically ventilated critically ill patients results in blood gas and/or hemodynamic abnormalities. DESIGN: A single-blind prospective study evaluated arterial blood gas, blood pressure, heart rate, and arrhythmia changes during mechanical ventilation and manual transport ventilation. SETTING: University hospital ICUs and various diagnostic or treatment areas. PATIENTS: Twenty mechanically ventilated critically ill patients during intrahospital transport. INTERVENTION: Each patient received mechanical ventilation (MECH) with a volume ventilator while in the ICU and at the study/treatment area. They were manually ventilated (MAN) by a respiratory therapist during transport between areas. MEASUREMENTS AND MAIN RESULTS: The MECH settings were: VT = 0.75 +/- 0.17 L; f = 16 +/- 4; VE = 12.6 +/- 4.3 L/min; FIO2 = 0.46 +/- 0.2. Mean peak Paw = 31 +/- 12 cm H2O and mean effective Cst = 44 +/- 15 ml/cm H2O. No hemodynamic abnormalities were observed. Arterial blood gas values did not vary to any clinically significant degree, except in two patients: one patient had a reduced PaO2 and increased PaCO2 associated with an accidental O2 disconnection and clamped chest tube; another patient had an increased pH by 0.13 units with only a 9 mm Hg fall in PaCO2. CONCLUSIONS: Manual ventilation during intrahospital transport of critically ill mechanically ventilated patients is safe provided the person performing manual ventilation knows the inspired oxygen fraction and minute ventilation required before transport and is trained to approximate them during transport.

Pulmonary embolism in respiratory failure.

The occurrence of pulmonary emboli in 617 patients admitted to a respiratory intensive care unit was studied. Pulmonary emboli were found in 18 (27 percent) of 66 autopsies. Half of these pulmonary emboli were not diagnosed before death, despite persistent aggressive attempts to document pulmonary emboli. In this subpopulation of patients with respiratory failure, the usual clinical manifestations of pulmonary emboli (symptoms, signs, chest x-ray film, electrocardiogram, and changes in arterial blood gas levels) frequently are already present, due to the severe underlying pulmonary disease, and any superimposed manifestations of pulmonary emboli are often inapparent. In this group under study, the ventilation/perfusion lung scan correlated poorly with pulmonary angiographic results and with examinations at autopsy; the scan generally was inadequate to rule in or rule out pulmonary emboli. Again, this was due to the distortion of both ventilation and perfusion by the severe underlying pulmonary disease. Currently, pulmonary angiographic studies remain the only reliable technique to confirm or exclude pulmonary emboli in patients with respiratory failure.

Depression of cardiac output is a mechanism of shunt reduction in the therapy of acute respiratory failure.

The relationship between changes in cardiac output and intrapulmonary shunt associated with mechanical ventilation was evaluated in 20 patients with the adult respiratory distress syndrome (ARDS). The distribution of ventilation-perfusion (VA/Q) ratios and the level of intrapulmonary shunt was determined by the multiple inert gas technique. Pulmonary blood flow was distributed predominantly to either effective gas-exchanging units or shunt units. Positive end-expiratory pressure (PEEP) or high tidal volume ventilation led to decreases in shunt and cardiac output without altering the overall pattern of VA/Q distributions. Changes in shunt and cardiac output were quantitatively and qualitatively silimar and a strong correlation was found between changes in shunt and cardiac output with both PEEP and high tidal volumes (r = 0.76). Cardiac output depression associated with tese modes of ventilation appears to be a mechanism of shunt reduction in ARDS. Interpretation of improvements in gas exchange in ARDS must take into account concomitant hemodynamic changes.

Transbronchial biopsy in the thrombocytopenic patient.

Twenty-five flexible fiberoptic bronchoscopic procedures with transbronchial lung biopsies were performed in 24 severely thrombocytopenic immunocompromised patients (mean platelet count of 30,000/cu mm, with a range of 7,000/cu mm to 60,000/cu mm) during the diagnostic evaluation of pulmonary infiltrates. Three patients had self-limited endobronchial bleeding. A single death was attributable to massive hemorrhage after transbronchial biopsy and brushing. Specific etiologic diagnoses were established by bronchoscopy in nine cases.

Transbronchial biopsy during mechanical ventilation.

The value and risk of transbronchial biopsy (TBB) was assessed in 15 cases requiring mechanical ventilation for progressive pulmonary infiltrates. TBB was diagnostic in five patients, and in two additional cases a diagnosis was made from the accompanying bronchial secretions. TBB results significantly altered the therapeutic management in seven cases. The alveolar-arterial gradient P(A-a)O2, widened by a mean of 110 mm Hg in nine patients; however, this change was transient and clinically insignificant. Three instances of reversible hypercapnia (mean of 15 mm Hg) occurred. Complications included self-limited bleeding in three cases and one tension pneumothorax. No fatalities were attributable to TBB. In these hemodynamically stable patients requiring mechanical ventilation for diffuse lung disease, TBB was performed safely and provided important data.

Tumor emboli presenting as pulmonary hypertension. A diagnostic dilemma.

A case of recurrent tumor emboli secondary to choriocarcinoma is described. The patient presented with obvious pulmonary hypertension and was diagnosed and treated as a case of multiple pulmonary embolism. Information which suggested the possibility of tumor emboli was indeed present but recognized only retrospectively.

Diagnosis of upper airway obstruction by pulmonary function testing.

We compared 11 patients with upper airway obstruction (obstruction at or proximal to the carina) to 22 patients with chronic obstructive pulmonary disease and to 15 normal subjects utilizing spirometry, lung volumes, airway resistance, maximal voluntary ventilation, single-breath diffusion capacity, and maximal inspiratory and expiratory flow-volume loops. Four values usually distinguished patients with upper airway obstruction: (1) forced inspiratory flow at 50 percent of the vital capacity (FIF50%) less than or equal to 100 L/min; (2) ratio of forced expiratory flow at 50 percent of the vital capacity of the FIR50% (FEF50%/FIF50%) larger than or equal to 1; (3) ratio of the forced expiratory volume in one second measured in milliliters to the peak expiratory flow rate in liters per minute (FEV1/PEFR) larger than or equal to 10 ml/L/min; and (4) ratio of the forced expired volume in one second to the forced expired volume in 0.5 second (FEV1/FEV0.5) larger than or equal to 1.5. The last ratio can be determined with a simple spirometer.

Aortobronchial fistula 13 years following repair of aortic transection.

We describe a 56-year-old man with the new onset of hemoptysis, increasing in frequency and magnitude, initially diagnosed and treated as pulmonary embolism. Bronchoscopy, computed tomography, and thoracic aortography were performed twice before the diagnosis was made. Thirteen years previously, the patient underwent thoracic aortic interposition graft placement for aortic laceration as a result of a motor vehicle accident. The second aortogram demonstrated a small pseudoaneurysm at the expected proximal graft suture line. Aortobronchial fistula, a rare cause of hemoptysis, was diagnosed. The patient underwent successful resection of the graft and placement of a new dacron interposition graft. All cultures, including blood, sputum, and operative specimen cultures, were negative. The patient is alive and well 1 year following surgery.

Long-term physiologic consequences of the adult respiratory distress syndrome.

Six survivors of the adult respiratory distress syndrome were studied. Measurements were made of lung volumes, flow rates, single-breath diffusing capacity for carbon dioxide (Dsb), arterial blood gas levels at rest and during exercise, the ratio of physiologic dead space to tidal volume (VD/VT), alveolar-arterial oxygen pressure difference (P[A-a]O2) and percent shunt (using an assumed arteriovenous oxygen content difference). At the time of study, which varied from 3 to 16 months after recovery, we found minor and inconsistent abnormalities in the lung volumes (reduced vital capacity in one patient, elevated residual volume [RV] in two, and reduced RV in three) and in the flow rates (reduced instantaneous forced expiratory flow after 50 percent of the forced vital capacity had been exhaled in two patients). In those tests having to do with transfer of gas, there were more abnormalities, consisting of a decreased Dsb in three patients, an elevated P(A-a)O2 in four, a low resting arterial oxygen pressure (PaO2) in two, a decrease in exercise PaO2 in three, an elevated shunt fraction (Qsan/Qt) in three, and an elevated VD/VT in one patient. Clinically, at the time of study, the patients all had returned to their status before illness.

The effect of tumor size and location on diagnosis by fiberoptic bronchoscopy.

Evaluation of data from fiberoptic bronchoscopic procedures revealed that for peripheral bronchogenic carcinomas, the diagnostic yield was influenced by the size of the lesion and its distance from the hilum. Failure to diagnose visible carcinomas was related to inability to obtain deep specimens for biopsy. Biopsy, brushing, and washing were complementary procedures in diagnosing bronchogenic carcinomas.

Clinical, laboratory, roentgenographic, and electrocardiographic findings in patients with acute pulmonary embolism and no pre-existing cardiac or pulmonary disease.

The history, physical examination, chest radiograph, electrocardiogram and blood gases were evaluated in patients with suspected acute pulmonary embolism (PE) and no history or evidence of pre-existing cardiac or pulmonary disease. The investigation focused upon patients with no previous cardiac or pulmonary disease in order to evaluate the clinical characteristics that were due only to PE. Acute PE was present in 117 patients and PE was excluded in 248 patients. Among the patients with PE, dyspnea or tachypnea (greater than or equal to 20/min) was present in 105 of 117 (90 percent). Dyspnea, hemoptysis, or pleuritic pain was present in 107 of 117 (91 percent). The partial pressure of oxygen in arterial blood on room air was less than 80 mm Hg in 65 of 88 (74 percent). The alveolar-arterial oxygen gradient was greater than 20 mm Hg in 76 of 88 (86 percent). The chest radiograph was abnormal in 98 of 117 (84 percent). Atelectasis and/or pulmonary parenchymal abnormalities were most common, 79 of 117 (68 percent). Nonspecific ST segment or T wave change was the most common electrocardiographic abnormality, in 44 of 89 (49 percent). Dyspnea, tachypnea, or signs of deep venous thrombosis was present in 107 of 117 (91 percent). Dyspnea or tachypnea or pleuritic pain was present in 113 of 117 (97 percent). Dyspnea or tachypnea or pleuritic pain was present in 113 of 117 (97 percent). Dyspnea or tachypnea or pleuritic pain or atelectasis or a parenchymal abnormality on the chest radiograph was present in 115 of 117 (98 percent). In conclusion, among the patients with pulmonary embolism that were identified, only a small percentage did not have these important manifestations or combinations of manifestations. Clinical evaluation, though nonspecific, is of considerable value in the selection of patients in whom there is a need for further diagnostic studies.

Diagnostic utility of ventilation/perfusion lung scans in acute pulmonary embolism is not diminished by pre-existing cardiac or pulmonary disease.

The purpose of this study was to assess the impact of prior cardiac or pulmonary disease upon the utility of ventilation/perfusion (V/Q) scans in the diagnosis of acute pulmonary embolism (PE). Ventilation/perfusion scans were evaluated among 365 patients with no prior cardiac or pulmonary disease and compared to V/Q scans in 526 patients with prior cardiac or pulmonary disease. Among patients with no prior cardiac or pulmonary disease, PE was present in 117 and PE was excluded in 248. Among patients with prior cardiac or pulmonary disease, PE was present in 140 and excluded in 386. The positive predictive value for PE of high probability V/Q scans among patients with prior cardiac or pulmonary disease, 55 of 66 (83 percent), was not significantly lower than among patients without prior cardiac or pulmonary disease, 50 of 54 (93 percent) (NS). The positive predictive value of low probability V/Q scans was similar with prior cardiac or pulmonary disease, 25 of 182 (14 percent), and without prior cardiac or pulmonary disease, 17 of 113 (15 percent) (NS), as was the predictive value of near normal/normal V/Q scans, 2 of 51 (4 percent), vs 3 of 79 (4 percent) (NS). The sensitivity of high probability V/Q scans, with pre-existing cardiac or pulmonary disease and without, 55 of 140 (39 percent) vs 50 of 117 (43 percent), did not differ significantly. The specificity of high probability V/Q scans with prior cardiac or pulmonary disease and without, 375 of 386 (97 percent) vs 244 of 248 (98 percent) was also similar (NS). In conclusion, the diagnostic utility of V/Q scans for acute PE was not impaired by the presence of pre-existing cardiac or pulmonary disease. Fewer patients, however, with no prior cardiac or pulmonary disease, had intermediate (indeterminate) V/Q scans.

Lung volume reduction surgery alters management of pulmonary nodules in patients with severe COPD.

OBJECTIVE: To examine the role of lung volume reduction surgery (LVRS) in expanding the treatment options for patients with single pulmonary nodules and emphysema. METHODS: Retrospective review of all patients undergoing LVRS at the University of Michigan between January 1995 and June 1996. Those undergoing simultaneous LVRS and resection of a suspected pulmonary malignancy formed the study group and underwent history and physical examination, pulmonary function tests, chest radiography, and high-resolution CT of the chest. If heterogeneous emphysema was found, cardiac imaging and single-photon emission CT perfusion lung scanning were performed. All study patients participated in pulmonary rehabilitation preoperatively. Age- and sex-matched patients who had undergone standard lobectomy for removal of pulmonary malignancy during the same period formed the control group. RESULTS: Of 75 patients who underwent LVRS, 11 had simultaneous resection of a pulmonary nodule. In 10 patients, the nodules were radiographically apparent with 1 demonstrating central calcification. Histologic evaluation revealed six granulomas, two hamartomas, and three neoplastic lesions (one adenocarcinoma, one squamous cell, and one large cell carcinoma). Preoperative FEV1 was 26.18+/-2.49% predicted in the LVRS group and 81.36+/-6.07% predicted (p=0.000001) in the control group, and the FVC was 65.27+/-5.17% predicted vs 92.18+/-5.53% predicted (p=0.002). Two LVRS patients had a PaCO2 >45 mm Hg while 11 exhibited oxygen desaturation during a 6-min walk test. Postoperative complications occurred in two LVRS patients and three control patients. The mean length of stay in the LVRS group (7.55+/-1.10 days) was not different than in the control group (8.81+/-1.56 days). Three months after LVRS and simultaneous nodule resection, FEV1 rose by 47%, FVC by 25%, and all study patients noted less dyspnea as measured by transitional dyspnea index. CONCLUSIONS: Simultaneous LVRS and resection of a suspected bronchogenic carcinoma is feasible and associated with minimal morbidity and significantly improved pulmonary function and dyspnea.

The diagnosis of acute pulmonary embolism in patients with chronic obstructive pulmonary disease.

The clinical features and noninvasive tests, including ventilation perfusion (V/Q) lung scans, were assessed in 108 patients with chronic obstructive pulmonary disease (COPD) suspected of having pulmonary embolism (PE). Twenty-one (19 percent) of 108 patients had PE. In the majority of patients, it was impossible to distinguish between patients with and without PE by clinical assessment alone. However, when a high clinical index of suspicion was present, PE was confirmed by angiography in three of three patients, but the V/Q scan was of intermediate probability. No roentgenographic abnormalities distinguished between PE and no PE. There was no difference between the alveolar-arterial oxygen gradients in either group, nor was there evidence of a reduction in the PaCO2 in patients with PE who had prior hypercapnia. Among the 108 patients with COPD, high, intermediate, low, and normal/near normal probability scans were present in 5 percent, 60 percent, 30 percent, and 5 percent, respectively. The frequency of PE in these V/Q scan categories was five (100 percent) of five, 14 (22 percent) of 65, two (6 percent) of 33, and zero (0 percent) of five, respectively. In conclusion, in the majority of patients, the V/Q scan diagnosis is usually intermediate and such patients require further investigational studies, including angiography. However, among the few patients who demonstrated a high probability lung scan, there was a high positive predictive value for PE effectively avoiding the need for further studies. In those patients with low probability or near normal/normal V/Q scans, the negative predictive value was not lower than the general hospital population.

Comparison of fenoterol, isoproterenol, and isoetharine with phenylephrine aerosol in asthma.

The bronchodilator effect of fenoterol hydrobromide (0.5, 1.25, and 2.5 mg) was compared with either isoproterenol (2.8 mg) or isoetharine (5 mg) with phenylephrine (1.25 mg) in a double-blind placebo-controlled study. When delivered by an intermittent positive-pressure breathing device to 24 nonsmoking young adult asthmatic subjects, fenoterol produced significant improvement in forced expiratory volume at 1 second (FEV1), in maximum midexpiratory flow (FEF25-75%), and in forced expiratory flow at 25 per cent of vital capacity (FEF25%) for 6 to 8 hours, whereas isoproterenol and isoetharine with phenylephrine produced improvement for 1 and 2 hours, respectively. The lowest dosage of fenoterol was as effective as the highest but had fewer adverse effects.