[Popliteal artery entrapment syndrome]. / Syndrome de l'artère poplitée piégée.

Popliteal entrapment is a rare compression syndrome involving vascular (and neurologic) structures of the popliteal fossa. In this article we review the popliteal artery entrapment syndrome (PAES). PAES is a cause of intermittent claudication that can be, although rarely, complicated with acute limb-threatening ischemia. PAES occurs more often in young adult. Concerning pathophysiology, PAES is provoked by an abnormal relationship between popliteal artery and muscular-tendon structures within the popliteal fossa. A surgical repair is usually required to resolve mechanical compression or vascular damage.

[Prevention of chronic venous disease: which advice for our patients?]. / Prévention de la maladie veineuse chronique: quels conseils donner à nos patients?

Chronic venous disease (CVD) is a major public health problem due to its high prevalence and socioeconomic costs. In absence of adequate care, it can lead to chronic venous insufficiency (CVI). Disturbed venous-flow patterns lead to venous hypertension. Therefore, prevention of CVD involves venous hypertension reduction. In primary prevention, it is essential to inform the patient about necessary lifestyle changes. In case of CVD, it is essential to propose treatment (compression, venoactive drugs, and interventional treatments) to avoid CVI appearance and eventually offer the best therapy solutions for CVI complications.

[Vascular follow up in patients suffering from peripheral arterial disease and undergoing revascularization]. / Suivi angiologique des patients artériopathes après geste de revascularisation.

The rapid evolution of revascularization techniques has allowed an improvement in quality of life of patients with peripheral artery disease. The angiological follow-up aims to insure durable results of revascularization, to diminish risk of amputation and to limit progression of atheroma plaques. The patient history and physical examination are essential in evaluating impact of peripheral artery disease upon quality of life and insuring the appropriate control of cardiovascular risk factors.

Safety of multidetector computed tomography pulmonary angiography to exclude pulmonary embolism in patients with a likely pretest clinical probability.

Essentials Safety of computed tomography (CTPA) to exclude pulmonary embolism (PE) in all patients is debated. We analysed the outcome of PE-likely outpatients left untreated after negative CTPA alone. The 3-month venous thromboembolic risk in these patients was very low (0.6%; 95% CI 0.2-2.3). Multidetector CTPA alone safely excludes PE in patients with likely clinical probability. SUMMARY: Background In patients with suspected pulmonary embolism (PE) classified as having a likely or high pretest clinical probability, the need to perform additional testing after a negative multidetector computed tomography pulmonary angiography (CTPA) finding remains a matter of debate. Objectives To assess the safety of excluding PE by CTPA without additional imaging in patients with a likely pretest probability of PE. Patients/Methods We retrospectively analyzed patients included in two multicenter management outcome studies that assessed diagnostic algorithms for PE diagnosis. Results Two thousand five hundred and twenty-two outpatients with suspected PE were available for analysis. Of these 2522 patients, 845 had a likely clinical probability as assessed by use of the simplified revised Geneva score. Of all of these patients, 314 had the diagnosis of PE excluded by a negative CTPA finding alone without additional testing, and were left without anticoagulant treatment and followed up for 3 months. Two patients presented with a venous thromboembolism (VTE) during follow-up. Therefore, the 3-month VTE risk in likely-probability patients after a negative CTPA finding alone was 2/314 (0.6%; 95% confidence interval [CI] 0.2-2.3%). Conclusions In outpatients with suspected PE and a likely clinical probability as assessed by use of the simplified revised Geneva score, CTPA alone seems to be able to safely exclude PE, with a low 3-month VTE rate, which is similar to the VTE rate following the gold standard, i.e. pulmonary angiography.

Inotropic and vasoactive drug treatment of interleukin 2 induced hypotension in sheep.

The side effects associated with recombinant interleukin 2 administration, including systemic hypotension and a vascular leak syndrome, may limit therapy before reaching maximum doses of this innovative and promising treatment for cancer. In an attempt to reverse this hypotension without decreasing cardiac output and systemic oxygen delivery (DO2), we studied several inotropic agents, dobutamine, dopamine, amrinone, CaCl2, and a pure alpha-adrenergic vasoconstrictor, methoxamine. These were administered singly or in combination to sheep with chronically implanted arterial and pulmonary artery catheters following 24 h of 3 x 10(5) units/kg recombinant interleukin 2. Compared to baseline values, 24 h of recombinant interleukin 2 infusion caused a significant increase in cardiac output from 4.4 +/- 0.9 (SD) to 5.0 +/- 0.6 liters/min, a significant fall in systemic vascular resistance (SVR) from 21 +/- 7 to 15 +/- 5 units, a decrease in mean systemic blood pressure (SBP) from 88 +/- 9 to 78 +/- 6 mm Hg, and a decrease in left ventricular stroke work from 51.5 +/- 8 to 49 +/- 6 gram meters (P less than 0.05) without any change in DO2. Dopamine, dobutamine, and CaCl2 returned SBP to baseline values by increasing cardiac output without increasing SVR. Methoxamine increased SBP by increasing SVR, but cardiac output decreased significantly. A combination of 12 micrograms/kg/min of dopamine and 2 to 3 mg of methoxamine infused over 15 min resulted in an increase in SBP, cardiac output, and SVR to baseline values while maintaining DO2 and oxygen consumption (VO2). We suggest that this latter combination would be appropriate for clinical use since it returns physiological parameters to normal.

Increase of rat pulmonary microvascular permeability to albumin by recombinant interleukin-2.

Immunotherapy with the lymphokine interleukin-2 (IL-2), with or without lymphokine activated killer (LAK) cells, offers a new approach to the treatment of solid tumors. Unfortunately, most patients receiving IL-2 and LAK cells develop a "third space syndrome" from a presumed generalized increase of vascular permeability. We have investigated the role of IL-2 on lung fluid balance, by measuring changes in lung water and albumin intake. Rats were injected with IL-2 500,000 U i.p. three times a day for 1 to 4 days. At the completion of the injections, lungs were isolated and perfused, and total lung water (TLW) and 125I-albumin uptake were measured. After 1 day of injections, TLW increased from 4.90 +/- 0.14 to 5.57 +/- 0.34 ml/g dry lung and albumin uptake nearly doubled from 0.47 +/- 0.08 to 0.91 +/- 0.28 cm3/s/g dry lung X 10(-3). Longer injection periods increased both TLW and albumin uptake further. After 2 days, TLW and albumin uptake were also significantly increased by 160,000 U i.p. three times a day, but not by 40,000 or 10,000 U. To eliminate possible contributions to increased permeability by (a) LAK cells generated in vivo, or (b) circulating leukocytes, we isolated lungs from normal rats and perfused them for 5 min with a cell-free perfusate containing IL-2 (2, 10, or 5 X 10(-3) U/ml) excipient or 0.9% NaCl placebo. TLW was similar in all groups, but albumin uptake was significantly increased by 10,000 and 50,000 U/ml (0.94 +/- 0.15 and 0.82 +/- 0.16 cm3/s/g dry lung X 10(-3), respectively), but not by 2,000 U/ml. We conclude that lung microvascular albumin permeability is increased following administration of IL-2 in vivo and in vitro. We suggest that LAK cells are not required for the initiation of increased permeability and that IL-2 may have some direct effect on the pulmonary microvasculature.

A comparison of the cardiopulmonary effects of continuous versus bolus infusion of recombinant interleukin-2 in sheep.

The systemic administration of recombinant interleukin-2 (rIL-2) is used for the treatment of patients with far advanced cancer. However, treatment may be limited by a so-called "third space" syndrome. Whether these side effects are due to the total dose used or the method of administration is unclear. To define whether the continuous (Group 2) or bolus (Group 3) i.v. infusion of 9 x 10(5) units/kg rIL-2 over 72 h is associated with similar toxicities, we established a chronic sheep model and monitored changes in systemic and pulmonary vascular pressures, cardiac function, and gas exchange. At 72 h lung lymph flow, lymph/plasma protein ratios, lung histology, and extravascular lung water/dry lung weight were obtained. In both groups the infusion of rIL-2 resulted in an increase in high protein lung lymph flow, an increase in cardiac output, and a decrease in systemic vascular resistance. Large lymphoid cells were found by histology to be infiltrating the lung interstitium. In Group 2, in addition, there were mild pulmonary hypertension [pulmonary artery pressures increased from 14 +/- 5 to 22 +/- 6 mmHg (P less than 0.05)], systemic hypotension [81 +/- 7 compared to a baseline of 95 +/- 9 mmHg (P less than 0.01)], and worsening gas exchange. We conclude that a 72-h continuous or bolus infusion of equivalent doses of rIL-2 are associated with cardiopulmonary toxicity; however, pulmonary hypertension, systemic hypotension, and gas exchange are worse in animals receiving the continuous infusion.

Pathophysiologic alterations in endotoxemia. Similarities to an animal model.

The validity of animal models of human sepsis has been questioned. We describe a patient who experienced a short episode of endotoxemia (? bacteremia) with resultant pulmonary hypertension, pulmonary edema from increased alveolar capillary membrane permeability, hypoxemia, hypotension, and relative leukopenia, which mimics the pathophysiologic changes noted following infusion of Pseudomonas bacteria into awake sheep. The similarity of abnormalities and their resolution suggests that Pseudomonas infusion in sheep is a valid experimental model of human septic shock.

Cardiopulmonary dynamics in a severe case of Rocky Mountain spotted fever.

A 19-year-old man had multisystem organ failure secondary to Rocky Mountain spotted fever. In addition to renal, cerebral, liver, and gastrointestinal tract involvement he manifested noncardiogenic pulmonary edema and, later, myocardial dysfunction. Aggressive surgical, medical, and monitoring procedures led to recovery. Previously suggested myocardial dysfunction was documented for the first time.

Physiologic and biochemical abnormalities in self-induced drug overdosage.

The following abnormalities were observed during the first 24 hours of admission for 162 drug overdosage (OD) episodes in 152 patients: abnormal chest x-ray films; increased A-aO2 gradient; elevated white blood cell (WBC) counts; elevated serum enzyme levels; gross myoglobinuria; skin lesions suggestive of pressure necrosis; and abnormal electrocardiograms. Many sputum cultures were positive for single or multiple potentially pathogenic organisms. These correlations existed: all patients with OD duration of less than 12 hours were hyperthermic; as temperatures increased so did WBC counts; hyperthermic patients had higher creatine phosphokinase (CPK) values than those with hypothermia or normothermia; patients with skin lesions had higher temperatures and CPK values and longer OD duration; serum enzme levels increased with increasing OD duration; patients with CPK levels greater than 10,000 mU/ml had myoglobinuria; and patients with the most abnormal chest x-ray films had higher temperatures and larger A-aO2 gradients. Incidence of pneumonitis is low, even with abnormal chest radiograms, leukocytosis, hyperthermia, and positive sputum cultures. Abnormal temperatures and leukocytosis are probably secondary to stress, hypoxemia, acidosis, and specific drug ingestion rather than infection.

Effects of isosorbide dinitrate on pulmonary hypertension in chronic obstructive pulmonary disease.

Eighteen patients with chronic obstructive pulmonary disease with pulmonary hypertension were studied to assess the hemodynamic response to acute oxygen administration and to oral isosorbide dinitrate (ISDN). All 18 patients had baseline hemodynamic measurements and hemodynamic measurements during low-flow nasal oxygen. Following a second baseline measurement, patients received either oral ISDN (11 patients) or placebo (7 patients) in a randomized, double-blind protocol. Heart rate decreased with oxygen administration but there were no other significant hemodynamic changes. With oral ISDN, there was a significant fall in pulmonary artery and brachial artery pressure. Cardiac output, right atrial pressure, pulmonary wedge pressure, and pulmonary vascular resistance all fell but not significantly. We conclude that oral ISDN is effective in reducing pulmonary hypertension in patients with chronic obstructive pulmonary disease.

In vivo interleukin-2 activated sheep lung lymph lymphocytes increase ovine vascular endothelial permeability by non-lytic mechanisms.

Therapeutic doses of recombinant interleukin-2 (rIL-2) often result in systemic toxicity consistent with increased vascular permeability. rIL-2 activated lymphocytes (IALs) may produce endothelial dysfunction and have cytolytic potential. However, much of the data on IAL cytotoxicity comes from the use of in vitro activated IALs. Alternatively, rIL-2 may enhance permeability directly or via release of various cytokines by host effector cells. The cytotoxicity of in vivo activated lung lymph lymphocytes has been studied in an ovine model of rIL-2 toxicity. The in vivo IALs had no significant endothelial cytolysis at effector to target ratios of 100:1. However, the in vivo IALs increased endothelial monolayer permeability to albumin, dependent on the concentration of IALs. rIL-2 induced no endothelial cytolysis or permeability alterations at doses of 10(5) and 2 x 10(5) U/ml, respectively. These findings suggest that the acute endothelial dysfunction characteristic of the vascular leak syndrome is not due to rIL-2 directly, but is mediated by in vivo IALs via non-cytolytic mechanisms and/or the release of secondary cytokines in response to rIL-2.

Effect of carbon monoxide on exercise performance in chronic obstructive pulmonary disease.

We evaluated the effect of breathing 100 ppm of carbon monoxide versus compressed, purified air for 1 hour on exercise performance in 10 patients with chronic obstructive pulmonary disease in a double-blind, randomized, crossover study. The mean arterial carboxyhemoglobin was 1.48 per cent in the carbon monoxide control period and increased from 1.43 to 4.08 per cent after breathing carbon monoxide (P less than 0.001). The mean arterial carboxyhemoglobin level was 1.52 percent in the air control period and decreased from 1.47 to 1.34 per cent after purified air (P less than 0.001). The mean exercise time until marked dyspnea decreased from 218.5 seconds in the carbon monoxide control period to 146.6 seconds after breathing carbon monoxide (P less than 0.001). The mean exercise time was 219.9 seconds in the air control period and 221.3 seconds after purified air (P not significant). Breathing 100 ppm of carbon monoxide for 1 hour caused a significant reduction in exercise performance in patients with chronic obstructive pulmonary disease.

Increased pulmonary artery pressure in association with Raynaud's phenomenon.

Pulmonary artery vasospasm is a hypothesized antecedent and etiologic factor in the pulmonary hypertension associated with progressive systemic sclerosis. Recent clinical data refute the existence of pulmonary vasospasm in a cohort of patients with scleroderma and normal baseline pulmonary artery pressure. A case of episodic pulmonary hypertension associated with a digital Raynaud's response is reported, and a cardiac mechanism is hypothesized.

Systemic hemodynamic and cardiac function changes in patients undergoing orthotopic liver transplantation.

The objective of this study was to determine the changes in systemic hemodynamics (systemic vascular resistance [SVR], cardiac output [CO], systemic blood pressure [SBP]) and cardiac function (pulmonary artery pressure [PAP] and pulmonary wedge pressure [PWP]) during the 96 hours following orthotopic liver transplantation (OLT) and correlate these with changes in hepatic and renal function and patient outcome. The study took place in a 12-bed medical respiratory intensive care unit in a large teaching hospital. Twenty-one patients had OLT performed over a 21.5-month period (January 1988 to October 15, 1989) for end stage liver disease (ESLD) from a variety of causes. A flow-directed right heart catheter and an indwelling arterial cannula were inserted for hemodynamic monitoring over a 96-hour postoperative period. Liver and renal function studies, total serum calcium, serum albumin, and fluid balance were determined daily. The SVR increased significantly to 12.8 +/- 0.6 U at 48 hours compared with immediate (less than 8 hours) postoperative levels (p less than 0.05) and remained elevated for 96 hours. The CO fell progressively and was significantly lower than baseline values from 64 to 96 hours. There was significant inverse correlation between the increase in SVR and the fall in CO (r = .85, p less than 0.01). The SBP was stable except for a small, but significant fall at 16 and 24 hours postoperatively. The PWP increased significantly from a baseline value of 12.5 +/- 0.9 mm Hg to 15 +/- 0.9 mm Hg at 32 hours and remained elevated through 96 hours (p less than 0.05). The serum bilirubin level fell progressively postoperatively and the prothrombin time and partial thromboplastin time (PTT) shortened significantly. Bile flow increased progressively from 107 +/- 120 ml/24 hours at the end of the first 24 hours to 188 +/- 125 ml/24 hours by 96 hours postoperatively. Five patients died from nine to 43 days postoperatively. These patients' hemodynamic parameters were not significantly different from the patients who survived. Successful OLT is associated with a rapid increase in SVR and a fall in CO without changes in SBP. These findings tend to parallel the improvement found in results of liver function tests. However, there is no correlation between the improvement in the hemodynamic state and long-term survival.

The uncertain role of the neutrophil in increased permeability pulmonary edema.

The intrapulmonic accumulation of neutrophils is a relatively common finding in certain animal models of increased permeability pulmonary edema and in humans with the adult respiratory distress syndrome. The release of toxic oxygen radicals from these cells can result in acute lung injury. Whether these cells mediate the increased permeability in all models of increased permeability pulmonary edema remains controversial. This review will examine the role of the neutrophils in various models of increased permeability pulmonary edema.

Suspected superior vena cava syndrome: the role of the Swan-Ganz catheter.

The use of the Swan-Ganz flow-directed catheter in establishing the diagnosis of the superior vena cava syndrome in two patients (one with Hodgkin's disease and the other with carcinoma of the lung) is described. A pressure tracing showing elevated pressure above the obstruction without respiratory or cardiac fluctuations is characteristic of obstruction of the superior vena cava.

The effect of oral hydralazine on the pulmonary hemodynamics of patients with pulmonary foreign body granulomatosis.

Six patients, age 32 +/- 5 yr, had biopsy-proven foreign body granulomatosis secondary to the chronic injection of crushed, suspended pentazocine tablets. All patients complained of exercise-induced dyspnea. Measurements were made of mean pulmonary artery pressures (PAP), cardiac outputs (CO), pulmonary vascular resistance (PVR), and systemic vascular resistance (SVR) at rest and following 9 minutes of steady-state upright exercise. Following this, 50 mg of hydralazine was administered orally. The exercise PAP increased, and exercise PVR following hydralazine rose also. Exercise-induced dyspnea improved in all patients. In patients with foreign body granulomatosis, exercise-induced increases in PAP and PVR are common. This increase in PAP and PVR can be ameliorated somewhat by the acute oral administration of hydralazine. Exercise-induced dyspnea also improves.

Pulmonary interstitial fibrosis following near-drowning and exposure to short-term high oxygen concentrations.

Following near-drowning in fresh water, a 19-year-old man experienced severe adult respiratory distress syndrome, necessitating ventilatory support with positive end-expiratory pressure and high oxygen concentrations. Post-extubation, his course was highlighted by persistent hypoxemia and interrupted by a lung abscess which responded promptly to antibiotics. Pulmonary function tests were consistent with severe restrictive disease and chest radiograph revealed persistent bilateral alveolar and interstitial infiltrates. An open lung biopsy on the 26th hospital day showed interstitial fibrosis. Over the ensuing two months, the chest radiograph and pulmonary function tests returned towards normal. We attribute the pulmonary fibrosis to incomplete resolution of the alveolar interstitial pathology secondary to the near-drowning and exposure to high oxygen mixtures.

Effects of carbohydrates on carbon dioxide excretion in patients with airway disease.

Thirteen patients with stable airway disease were fed a diet high in carbohydrates, and 35 minutes later metabolic and ventilatory effects were observed. The six patients who did not retain carbon dioxide increased their mean respiratory quotient from 0.86 +/- 0.07 to 1.03 +/- 0.04, their mean minute ventilation from 10.3 +/- 3.0 to 12.8 +/- 4.0 L/min, mean carbon dioxide production from 0.23 +/- 0.04 to 0.29 +/- 0.02 L/min, and mean oxygen consumption from 0.27 +/- 0.07 to 0.29 +/- 0.03 L/min (all P less than 0.05). The arterial carbon dioxide tension (PaCO2) did not change significantly from baseline values. The seven patients who retained carbon dioxide responded similarly, except that their mean arterial oxygen pressure (PaO2) increased significantly from 50.9 +/- 4.4 to 57.7 +/- 5.5 torr (P less than 0.05). In addition, the mean PaCO2 increased from 54.5 +/- 6.4 to 54.9 +/- 6.4 torr (not significant). We conclude that the increased endogenous carbon dioxide load resulting from a meal high in carbohydrates is well tolerated by most patients with chronic airway disease.