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J W Leatherman

Publications and source records attributed to J W Leatherman.

At least 19 recordsLinked to original sources
PubMed1999

Right heart catheterization in acute lung injury: an observational study.

Right heart catheterization (RHC) is commonly used in the diagnosis and management of acute lung injury (ALI). However, controversy exists regarding RHC. We examined RHC use during the first 3 d of ALI in an observational study of 135 patients defined by American-European Consensus Conference criteria. Study parameters examined for association with RHC included the Acute Physiology and Chronic Health Evaluation (APACHE) III score, lung injury score (LIS), and 20 additional epidemiologic, clinical, and laboratory parameters. RHC was performed in 70 patients (52%) within the first 3 d of ALI. RHC was positively associated (p < 0.05) with a diagnosis of sepsis, APACHE III score, blood urea nitrogen (BUN), creatinine, net fluid balance, and positive end-expiratory pressure. RHC was negatively associated (p < 0.05) with mean arterial pressure (Pa) and PaO2/FIO2. Logistic regression identified four predictors for RHC placement: sepsis, PaO2/FIO2, BUN, and Pa. Initial right atrial and pulmonary artery occlusion pressure measurements demonstrated a moderately strong correlation (r = 0.72). Use of RHC was associated with a change in one or more therapeutic interventions (intravascular fluids, vasopressors, diuretics) in 78% of patients. In summary, patients receiving RHC during the first 3 d of ALI were more severely ill than those who did not receive RHC, and RHC was associated with a change in therapy in most patients.

APACHE↗
PubMed1998

Right ventricular end-diastolic volume as a predictor of the hemodynamic response to a fluid challenge.

OBJECTIVE: To compare thermodilution right ventricular end-diastolic volume index (RVEDVI) and pulmonary artery occlusion pressure (Ppao) as predictors of the hemodynamic response to a fluid challenge. DESIGN: Prospective cohort study. SETTING: Medical ICU of a university-affiliated county hospital and medical-surgical ICU of a community hospital. PATIENTS: Twenty-five critically ill patients who had one or more clinical conditions that suggested the possibility of inadequate preload. INTERVENTIONS: Thirty-six fluid challenges. Fluid (saline or colloid) was administered rapidly until the Ppao rose by at least 3 mm Hg. When a patient underwent more than one fluid challenge, these were given on separate days and for different clinical indications. MEASUREMENTS AND RESULTS: Responders (n=20; > or = 10% increase in stroke volume [SV]) and nonresponders (n=16; <10% increase in SV) differed with respect to baseline Ppao (10.0+/-3.4 vs 14.2+/-3.6 mm Hg; p=0.001), but not with respect to baseline RVEDVI (105+/-31 vs 119+/-33 mL/m2; p=0.22). There was a moderate correlation between RVEDVI and fluid-induced change in SV (r=0.44); the relationship between Ppao and change in SV was stronger (r=0.58). A positive response to fluid was observed in 4 of 9 cases in which RVEDVI exceeded 138 mL/m2, a threshold value that has been suggested to reliably predict a poor response to fluid. CONCLUSION: RVEDVI was not a reliable predictor of the response to fluid. As a predictor of fluid responsiveness, Ppao was superior to RVEDVI. In an individual patient, adequacy of preload is best assessed by an empiric fluid challenge.

Adult↗
PubMed1998

EMG findings in acute myopathy with status asthmaticus, steroids and paralytics. Clinical and electrophysiologic correlation.

We have reviewed the clinical and electrophysiologic features of eleven mechanically ventilated patients with asthma who developed persistent weakness following treatment with neuromuscular blocking agents and corticosteroids. All patients had electrophysiologic findings consistent with a myopathic process and no evidence of a neuromuscular transmission disorder or generalized neuropathy. Electrophysiologic improvement paralleled clinical improvement. The severity of the initial electrophysiologic findings did not predict the subsequent rate of recovery. All patients showed substantial recovery (to functional independence) over the first month.

Adrenal Cortex Hormones↗
PubMed1997

Interpretation of the pulmonary artery occlusion pressure in mechanically ventilated patients with large respiratory excursions in intrathoracic pressure.

OBJECTIVE: To assess the reliability of the pulmonary artery occlusion pressure (Ppao) when respiratory excursions in intrathoracic pressure are prominent. DESIGN: We studied 24 critically ill patients who had 15 mm Hg or more of respiratory excursion in their Ppao tracing. Large respiratory excursions resulted from respiratory muscle activity that persisted despite sedation and mechanical ventilation in the assist-control mode. From the Ppao tracing, the end-expiratory and mid-point values were recorded; the latter was measured halfway between end-expiration and the nadir due to inspiratory triggering. The Ppao was then re-measured after administration of a non-depolarizing muscle relaxant. SETTING: Medical intensive care unit of a university-affiliated teaching hospital. MEASUREMENTS AND RESULTS: The difference between the pre-relaxation end-expiratory Ppao and the relaxed Ppao was larger than the difference between the pre-relaxation mid-point Ppao and the relaxed Ppao (11 +/- 5 vs 3 +/- 3 mm Hg, p < 0.01). In 21 of 24 (88%) cases, the relaxed Ppao was more closely approximated by the mid-point Ppao than by the end-expiratory Ppao. The difference between the end-expiratory Ppao and the relaxed Ppao increased as the amount of respiratory excursion increased (r = 0.51; p < 0.01). CONCLUSIONS: In mechanically ventilated patients whose respiratory muscles produce large excursions in the Ppao, the end-expiratory Ppao is often much higher than the Ppao measured after muscle relaxation. The pre-relaxation mid-point Ppao and the relaxed Ppao are usually similar, but this may not be true in individual patients. In this setting, the Ppao measured after muscle relaxation probably provides the most clinically reliable estimate of left heart filling pressure.

Adult↗
PubMed1996

Mechanical ventilation in obstructive lung disease.

This article reviews selected topics relevant to the use of mechanical ventilation in patients with severe airflow obstruction. Areas discussed include the bedside assessment of respiratory system mechanics, the ventilatory determinants of dynamic pulmonary hyperinflation, the role of controlled hypoventilation with permissive hypercapnia, and the delivery of bronchodilators during mechanical ventilation.

Adrenal Cortex Hormones↗
PubMed1996

Low measured auto-positive end-expiratory pressure during mechanical ventilation of patients with severe asthma: hidden auto-positive end-expiratory pressure.

OBJECTIVE: To describe the occurrence of low measured auto-end-expiratory pressure (auto-PEEP) during mechanical ventilation of patients severe asthma. DESIGN: Observational clinical study. SETTING: Medical intensive care unit of a university-affiliated county hospital. PATIENTS: Four mechanically ventilated patients with severe asthma who had low measured auto-PEEP despite marked increase in both peak and plateau airway pressures. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Peak pressure, plateau pressure, and auto-PEEP were measured at an early time point, when airflow obstruction was most severe, and again at a later time after clinical improvement. Auto-PEEP was measured by the method of end-expiratory airway occlusion. From the early to the late point, there was a marked decrease in peak pressure (76 +/- 7 to 53 +/- 6 cm H2O; p<.001) and in plateau pressure (28 +/- 2 to 18 +/- 3 cm H2O; p<.001), but only minimal change in auto-PEEP (5 +/- 3 to 4 +/- 3 cm H2O). The difference between plateau pressure and auto-PEEP decreased between the early and late time points (23 +/- 1 to 14 +/- 1 cm H2O; p<.01), even though tidal volume was larger at the late time point. In three patients, low auto-PEEP and a large difference between plateau pressure and auto-PEEP was only seen after expiratory time was prolonged. In these three patients, prolongation of expiratory time resulted in a large decrease in measured auto-PEEP (14 +/- 4 to 5 +/- 4 cm H2O), but a much smaller change in plateau pressure (31 +/- 3 to 29 +/- 3 cm H2O). CONCLUSIONS: We conclude that measured auto-PEEP may underestimate end-expiratory alveolar pressure in severe asthma, and that marked pulmonary hyperinflation may be present despite low measured auto-PEEP, especially at low respiratory rates. This phenomenon may be due to widespread airway closure that prevents accurate assessment of alveolar pressure at end-expiration.

Acute Disease↗
PubMed1996

Muscle weakness in mechanically ventilated patients with severe asthma.

Patients who undergo mechanical ventilation for severe asthma are at risk of developing diffuse muscle weakness because of acute myopathy. The relative importance of corticosteroids and neuromuscular paralysis in causing the myopathy is controversial, and it is uncertain whether the chemical structure of the drug used to induce paralysis influences the risk of myopathy. Using a retrospective cohort study design, we evaluated 107 consecutive episodes of mechanical ventilation for severe asthma to assess (1) the incidence of clinically significant weakness in patients treated with corticosteroids alone versus corticosteroids with neuromuscular paralysis, (2) the influence of the duration of paralysis on the incidence of muscle weakness, and (3) the relative risk of weakness in patients paralyzed with the nonsteroidal drug atracurium versus an aminosteroid paralytic agent (pancuronium, vecuronium). The use of corticosteroids and a neuromuscular blocking agent was associated with a much higher incidence of muscle weakness as compared with the use of corticosteroids alone (20 of 69 versus O of 38, p < 0.001). The 20 weak patients were paralyzed significantly longer than the 49 patients who received a neuromuscular blocking agent without subsequent weakness (3.4 +/- 2.4 versus 0.6 +/- 0.7 d, p < 0.001). Eighteen of the 20 weak patients had been paralyzed for more than 24 h. The incidence of weakness was not reduced when paralysis was achieved with atracurium as opposed to an aminosteroid neuromuscular blocking agent. In conclusion, corticosteroid-treated patients with severe asthma who undergo prolonged neuromuscular paralysis are at significant risk for the development of muscle weakness, and the risk of weakness is not reduced by use of atracurium.

Acute Disease↗
PubMed1992

Intrapleurally administered streptokinase in the treatment of acute loculated nonpurulent parapneumonic effusions.

Adequate pleural drainage is believed to be an essential component of the management of low pH-low glucose parapneumonic effusion. Parapneumonic effusions may become loculated rapidly, preventing adequate drainage with a single chest tube. Administration of intrapleural streptokinase may be effective in promoting drainage for loculated, nonpurulent low pH-low glucose parapneumonic effusions when fibrin adhesions may not yet be organized. Intrapleural streptokinase was used in 12 patients with relatively large, symptomatic, loculated, nonpurulent parapneumonic effusions in whom the initial thoracentesis demonstrated a pH less than or equal to 7.0 and/or glucose less than or equal to 40 mg/dl, and when inadequate drainage was demonstrated roentgenographically despite tube thoracostomy. Mean pleural fluid WBC was 9,750/mm3 (range, 1 to 27 K), and pleural fluid glucose and pH were 33 +/- 21 mg/dl and 6.95 +/- 0.19, respectively. A solution of streptokinase, 250,000 units in normal saline, was given intrapleurally via the chest tube. Effectiveness of intrapleural streptokinase was assessed radiographically and by monitoring the volume of fluid drained from the chest tube after streptokinase instillation. A greater than 50% improvement in the CXR was seen in nine of 12 patients after intrapleural administration of streptokinase. The volume of fluid out in the first 48 h post-streptokinase was 849 +/- 836 ml (range, 100 to 3,000). In addition, clinical improvement (decreased chest discomfort, less dyspnea, or reduced fever) was noted in eight of 12 patients after streptokinase treatment. We conclude that intrapleural administration of streptokinase is an effective adjunct to the management of nonpurulent, loculated parapneumonic effusions that may reduce the need for multiple chest tubes or surgical drainage.

Acute Disease↗
PubMed1992

Intracardiac mural thrombus mimicking atrial myxoma in the antiphospholipid syndrome.

A wide spectrum of cardiac involvement including valvular lesions, myocardial infarction and myocardial dysfunction has been reported in patients with antiphospholipid antibodies (aPL), suggesting that cardiac manifestations may be part of the antiphospholipid syndrome (APS). We describe 3 patients (2 with primary APS and one with APS and SLE) who were found to have right atrial masses by echocardiography (transthoracic and/or transesophageal) and/or angiography, which were felt preoperatively to be atrial myxomata. Pathological examination of resected material showed only organized thrombus with calcification. We describe outcome 12 months to 7 years after resection of thrombus and document possible recurrence in one patient after 7 years. Intracardiac mural thrombus may be an additional cardiac manifestation of the APS, and presents considerable diagnostic confusion in its differentiation from atrial myxomata.

Adolescent↗
PubMed1991

Fever, hyperdynamic shock, and multiple-system organ failure. A pseudo-sepsis syndrome associated with chronic salicylate intoxication.

OBJECTIVE: To describe a sepsis-like syndrome associated with chronic salicylate intoxication. DESIGN: Retrospective clinical study. SETTING: University-affiliated county hospital. PATIENTS: Five patients who became accidentally intoxicated while ingesting salicylates on a long-term daily basis. RESULTS OF DATA ANALYSIS: All five salicylate-intoxicated patients had clinical and laboratory features that were highly suggestive of sepsis, but no bacteriologic or pathologic evidence of infection could be documented. Features included fever, leukocytosis with increased band forms, hypotension with a reduced SVR and multiple system organ failure (ARDS, encephalopathy, renal failure, and DIC). A diagnosis of salicylate intoxication was made at the time of admission to the hospital in only one case. In the other four cases, the presumptive diagnosis was sepsis; a correct diagnosis of salicylate intoxication was not established until between 16 h and 10 days after admission in these four cases. Two patients died, one patient required permanent hemodialysis, and two patients recovered fully only after prolonged and complicated hospitalizations. The pathogenesis of this syndrome is uncertain. In two cases, serum levels of TNF-alpha, IL-1 beta and IL-6 were measured by ELISA. In both cases serum IL-6 was markedly increased, and in one case serum TNF-alpha was also elevated. CONCLUSION: Occult salicylate intoxication should be considered when apparent sepsis syndrome occurs without a readily easily identifiable source of infection.

Adult↗
PubMed1991

Tidal volume reduction in ARDS. Effect on cardiac output and arterial oxygenation.

During continuous positive pressure ventilation (CPPV), mean airway pressure and lung volume will be influenced both by the tidal volume (VT) employed and the amount of positive end-expiratory pressure (PEEP). The effect of varying levels of CPPV on PaO2 and cardiac output (Q) has been previously assessed by adjusting the level of PEEP at constant VT. This study examined the influence of a 200-ml reduction in VT, at a constant PEEP of 15 cm H2O, on the PaO2 and Q of 21 patients with adult respiratory distress syndrome (ARDS). The relationship between change in Q and change in total respiratory system compliance (Cst) after VT reduction was also examined. VT reduction from 14.1 +/- 0.8 ml/kg to 11.2 +/- 0.9 ml/kg yielded an increase in Q (+ 15 +/- 12 percent, p less than 0.01) without a significant change in PaO2 (-6.3 +/- 15.0 mm Hg, p = 0.08). Cst increased with VT reduction (+ 3.1 +/- 1.8 ml/cm H2O). There was only a modest correlation (r = +0.42, p = 0.06) between delta Q percent and delta Cst following VT reduction. VT reduction at high level PEEP may yield a significant improvement in Q and net O2 delivery, but the degree of hemodynamic improvement is variable and is not reliably predicted noninvasively by measurement of Cst.

Adult↗
PubMed1988

The lung in systemic vasculitis.

Pulmonary vasculitis is usually caused by one of three disorders: (1) Wegener's granulomatosis (WG); (2) Churg-Strauss syndrome (CSS), or allergic angiitis and granulomatosis; or (3) a nonspecific small vessel systemic necrotizing vasculitis (SNV), or microscopic polyarteritis. WG, the most common cause of lung vasculitis, has features of a granulomatous vasculitis of the upper airway and lung and widespread small vessel vasculitis involving the kidneys and other organs. The features of pulmonary WG overlap with those of malignancy and infectious granulomatous lung disease; accurate diagnosis generally requires open lung biopsy. CSS is defined by the triad of asthma, eosinophilia, and systemic vasculitis. Easily accessible tissues should be biopsied, but the clinical features are so distinctive that tissue biopsy is not invariably required for diagnosis. CSS must be differentiated from other diseases that cause pulmonary infiltrates with eosinophilia, including infections. Nonspecific SNV causes diffuse alveolar hemorrhage due to pulmonary capillaritis. Concomitant segmental necrotizing glomerulonephritis is almost always present. Diagnosis is made by renal biopsy, compatible extrarenal features, exclusion of nonimmune causes of lung hemorrhage, and exclusion of WG to the extent possible.

Churg-Strauss Syndrome↗
PubMed1988

Respiratory manifestations of connective tissue disease.

Pleuropulmonary disease is a common feature of the following connective tissue diseases: systemic lupus erythematosis (SLE), rheumatoid arthritis (RA), progressive systemic sclerosis (PSS), mixed connective tissue disease (MCTD), polymyositis/dermatomyositis (PM/DM), and Sjogren's syndrome (SS). Features common to most of these disorders include pleurisy with effusion and interstitial lung disease. Pleural effusions caused by SLE and RA have certain characteristics on pleural fluid analysis that aid in diagnosis, but infection and other causes of effusion must be excluded. Interstitial lung involvement is usually indolent in onset, but a more rapidly progressive course over weeks to a few months may mimic infection. Several drugs used to treat connective tissue diseases may cause interstitial disease, increase susceptibility to infection, or both. This complicates differential diagnosis. Acute lupus pneumonitis and SLE-related alveolar hemorrhage are usually fulminant processes, often associated with fever. Diagnosis of these conditions always requires exclusion of infection. Rheumatoid nodules may mimic infectious and neoplastic lung diseases. Needle biopsy helps reduce the likelihood of infection or malignancy, but open lung biopsy is needed if a firm diagnosis of rheumatoid nodules is required.

Arthritis, Rheumatoid↗
PubMed1987

Aminophylline for acute exacerbations of chronic obstructive pulmonary disease. A controlled trial.

STUDY OBJECTIVE: To determine the efficacy of intravenous aminophylline in the treatment of patients hospitalized for exacerbation of chronic obstructive pulmonary disease. DESIGN: Randomized, double-blind, placebo-controlled trial during the first 72 hours of hospitalization. PATIENTS: Thirty patients admitted from the emergency room or walk-in clinic with the primary diagnosis of an exacerbation of chronic obstructive pulmonary disease. Twenty-eight patients completed the study; 2 patients, 1 receiving placebo and 1 receiving aminophylline, were removed from the study because of respiratory failure requiring mechanical ventilation. INTERVENTIONS: PATIENTS received either intravenous aminophylline or placebo, in addition to nebulized, inhaled 0.3 mL of a 5% solution every 6 hours; methylprednisolone, 0.5 mg/kg body weight every 6 hours intravenously; ampicillin, 500 mg orally every 6 hours (tetracycline or trimethoprim-sulfamethoxazole were substituted in penicillin-allergic patients); and supplemental oxygen as needed. Aminophylline infusion rates were adjusted by an unblinded investigator to achieve theophylline levels of 72 to 83 mumol/L. Changes were also made in placebo infusion rates to maintain the double-blind design. MEASUREMENTS AND MAIN RESULTS: The forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) before and after metaproterenol inhalation were measured twice daily by a blinded investigator, who also administered a verbal dyspnea index with a scale of 1 to 10 and questioned patients regarding possible side effects of treatment (tremor, palpitations, nausea, or vomiting). Arterial blood gas measurements at 72 hours were compared with those obtained on admission. Significant improvements in FEV1 and FVC measured before and after metaproterenol treatment and in dyspnea occurred over time in both treatment groups (p less than 0.05 for all measurements). However, there were no significant differences between the placebo and aminophylline groups in any of the spirometric measurements or the dyspnea indices (p greater than 0.5 in all five analyses). The mean increases (+/- SE) in Po2 of 1.9 (+/- 0.5) kPa with placebo and 1.7 (+/- 0.7) kPa with aminophylline and the mean decreases in PCO2 of 0.5 (+/- 0.4) kPa with placebo and 1.2 (+/- 0.4) kPa with aminophylline were not significantly different (p greater than 0.6 for PO2, p greater than 0.2 for PCO2).(ABSTRACT TRUNCATED AT 400 WORDS)

Acute Disease↗
PubMed1985

Fluid-containing bullae in the lung.

Eight patients had air-fluid levels in the lung as a result of fluid accumulation in preexisting bullae. In four cases the cause was peribullous pneumonitis; in the other four cases the cause could not be determined. All patients had a favorable clinical course while intrabullous fluid was present. The initial interpretation of air-fluid levels was correct in only two instances. Differentiation of fluid-containing bullae from other causes of air-fluid levels is important so that unnecessary diagnostic and therapeutic maneuvers can be avoided.

Aged↗