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BACKGROUND Despite many improvements in percutaneous coronary intervention (PCI) and hospital systems of care, delay in seeking medical attention remains a significant barrier to timely reperfusion in acute coronary syndromes (ACS). Though previous studies have examined the risk factors associated with prolonged delays in accessing care, the data on education interventions to mitigate these factors is mixed. The aim of this systematic review is to examine the overall efficacy and methods of intervention available to minimize these delays. METHODS AND RESULTS We searched EMBASE, PubMED and MEDLINE from their inception to January 2021. Studies examining the association between either education intervention or mass media campaigns and delays in care (both patient delay and/or healthcare system delay) in ACS were included. Two independent reviewers performed level 1 screening of 6256 abstracts, which resulted in 95 studies for level 2 screening. After full manuscript review, these studies were then tailored to 26 studies with 17 companion articles for final data extraction. See Figure 1. In total, 20 studies used mass media campaigns, 5 targeted high-risk populations and 1 used a combination of both strategies (see Table 1). The key messages of these interventions were to appropriately identify ACS symptoms, and to call emergency medical services (EMS) for timely access to care. The majority of studies examined the effect on patient delays in care (n=15), of which 80% were effective. The use of EMS in the setting of potential ACS (n=14) was increased in 64% of studies after the intervention. There were also two studies that demonstrated decreased infarct size and mortality post-intervention. Several studies examined patient knowledge outcomes alone (n=4). In all studies examined, educational elements and mass media interventions relied heavily on print materials, radio and television. There was little to no presence of internet-based resources or social media. CONCLUSION Despite significant heterogeneity, there is evidence to support the efficacy of education interventions to reduce delay in patients with chest pain. The use of similar methods using an internet-based platform is an interesting possibility that has not yet been explored in the current body of literature.

The demonstration that angiogenic growth factors can stimulate new blood vessel growth and restore perfusion in animal models of myocardial ischemia has led to the development of strategies designed for the local production of angiogenic growth factors in patients who are not candidates for conventional revascularization. The results of recent clinical trials of proangiogenesis gene therapy have been disappointing; however, significant limitations in experimental design, in particular in gene transfer strategies, preclude drawing definitive conclusions. In the REVASC study cardiac gene transfer was optimized by direct intramyocardial delivery of a replication-deficient adenovirus-containing vascular endothelial growth factor (AdVEGF121, 4 x 10(10) particle units (p.u.)). Sixty-seven patients with severe angina due to coronary artery disease and no conventional options for revascularization were randomized to AdVEGF121 gene transfer via mini-thoracotomy or continuation of maximal medical treatment. Exercise time to 1 mm ST-segment depression, the predefined primary end-point analysis, was significantly increased in the AdVEGF121 group compared to control at 26 weeks (P=0.026), but not at 12 weeks. As well, total exercise duration and time to moderate angina at weeks 12 and 26, and in angina symptoms as measured by the Canadian Cardiovascular Society Angina Class and Seattle Angina Questionnaire were all improved by VEGF gene transfer (all P-values at 12 and 26 weeks < or =0.001). However, if anything the results of nuclear perfusion imaging favored the control group, although the AdVEGF121 group achieved higher workloads. Overall there was no significant difference in adverse events between the two groups, despite the fact that procedure-related events were seen only in the thoracotomy group. Therefore, administration of AdVEGF121 by direct intramyocardial injections resulted in objective improvement in exercise-induced ischemia in patients with refractory ischemic heart disease.

This study was a retrospective analysis of injuries sustained by women (mean age 60.9) who completed a 24-week walking intervention. We hypothesized that those who walked 60 min, 5 days/week (n = 27) were more likely to have an injury than those who walked 3 days/week (n = 27), and that predisposing conditions would lead to more injuries. We also examined the effect of the initial 4 weeks’ walking progression on likelihood of injury. A total of 12% of the walkers reported injuries necessitating program withdrawal, 18% reported minor injuries, and 26% reported injuries requiring medical treatment. Age, weight, cardiovascular fitness level, and walking volume were not significantly related to injuries. Women with prior musculoskeletal conditions were more likely to sustain injuries requiring medical treatment (p < .01). For these women, the initial progression may have been too rapid, suggesting that musculoskeletal screening and gradual progression guided by staff is important for moderate as well as intense activity programs.

We investigated the effects of hypoxic ventilation on the pulmonary arterial pressure- (P) flow (Q) relationship in an intact canine preparation. Mean pulmonary P-Q coordinates were obtained during hypoxic ventilation and during ventilation with 100% O2 at normal and at increased left atrial pressure. Specifically, we tested the hypothesis that, over a wide range, changes in left atrial pressure would alter the effects of hypoxic ventilation on pulmonary P-Q characteristics. Seven dogs were studied. When left atrial pressure was normal (5 mmHg), the mean value of the extrapolated intercept (PI) of the linear P-Q relationship was 10.9 mmHg and the slope (incremental vascular resistance, IR) of the P-Q relationship was 2.2 mmHg.l-1.min. Hypoxic ventilation increased PI to 18 mmHg (P less than 0.01) but did not affect IR. Subsequently, during ventilation with 100% O2, when left atrial pressure was increased to 14 mmHg by inflation of left atrial balloon, PI increased to 18 mmHg. IR was 1.6 mmHg.l-1.min. Again, hypoxic ventilation caused an isolated change in PI. Hypoxia increased PI from 18 to 28 mmHg (P less than 0.01). As in the condition of normal left atrial pressure, hypoxic ventilation did not affect IR. We conclude that, in an anesthetized intact canine preparation, hypoxic ventilation causes an isolated increase in the extrapolated pressure intercept of the pulmonary P-Q relationship. Furthermore the effects of hypoxic ventilation on pulmonary P-Q characteristics are not affected by the resting left atrial pressure.

Inhibition of the platelet glycoprotein IIb/IIIa receptor with the monoclonal-antibody fragment abciximab reduces the acute ischemic complications associated with percutaneous coronary revascularization, whereas coronary-stent implantation reduces restenosis. We conducted a trial to determine the efficacy of abciximab and stent implantation in improving long-term outcome.A total of 2399 patients were randomly assigned to stent implantation and placebo, stent implantation and abciximab, or balloon angioplasty and abciximab. The patients were followed for six months.At six months, the incidence of the composite end point of death or myocardial infarction was 11.4 percent in the group that received a stent and placebo, as compared with 5.6 percent in the group that received a stent and abciximab (hazard ratio, 0.47; 95 percent confidence interval, 0.33 to 0.68; P0.001) and 7.8 percent in the group assigned to balloon angioplasty and abciximab (hazard ratio, 0.67; 95 percent confidence interval, 0.49 to 0.92; P=0.01). The hazard ratio for stenting plus abciximab as compared with angioplasty plus abciximab was 0.70 (95 percent confidence interval, 0.48 to 1.04; P=0.07). The rate of repeated revascularization of the target vessel was 10.6 percent in the stent-plus-placebo group, as compared with 8.7 percent in the stent-plus-abciximab group (hazard ratio, 0.82; 95 percent confidence interval, 0.59 to 1.13; P=0.22) and 15.4 percent in the angioplasty-plus-abciximab group (hazard ratio, 1.49; 95 percent confidence interval, 1.13 to 1.97; P=0.005). The hazard ratio for stenting plus abciximab as compared with angioplasty plus abciximab was 0.55 (95 percent confidence interval, 0.41 to 0.74; P0.001). Among patients with diabetes, the combination of abciximab and stenting was associated with a lower rate of repeated target-vessel revascularization (8.1 percent) than was stenting and placebo (16.6 percent, P=0.02) or angioplasty and abciximab (18.4 percent, P=0.008).For coronary revascularization, abciximab and stent implantation confer complementary long-term clinical benefits.

The TIMI 14 trial tested the hypothesis that abciximab, the Fab fragment of a monoclonal antibody directed to the platelet glycoprotein (GP) IIb/IIIa receptor, is a potent and safe addition to reduced-dose thrombolytic regimens for ST-segment elevation MI.Patients (n=888) with ST-elevation MI presenting12 hours from onset of symptoms were treated with aspirin and randomized initially to either 100 mg of accelerated-dose alteplase (control) or abciximab (bolus 0.25 mg/kg and 12-hour infusion of 0.125 microg. kg-1. min-1) alone or in combination with reduced doses of alteplase (20 to 65 mg) or streptokinase (500 000 U to 1.5 MU). Control patients received standard weight-adjusted heparin (70-U/kg bolus; infusion of 15 U. kg-1. h-1), whereas those treated with a regimen including abciximab received low-dose heparin (60-U/kg bolus; infusion of 7 U. kg-1. h-1). The rate of TIMI 3 flow at 90 minutes for patients treated with accelerated alteplase alone was 57% compared with 32% for abciximab alone and 34% to 46% for doses of streptokinase between 500 000 U and 1.25 MU with abciximab. Higher rates of TIMI 3 flow at both 60 and 90 minutes were observed with increasing duration of administration of alteplase, progressing from a bolus alone to a bolus followed by either a 30- or 60-minute infusion (P0.02). The most promising regimen was 50 mg of alteplase (15-mg bolus; infusion of 35 mg over 60 minutes), which produced a 76% rate of TIMI 3 flow at 90 minutes and was tested subsequently in conjunction with either low-dose or very-low-dose (30-U/kg bolus; infusion of 4 U. kg-1. h-1) heparin. TIMI 3 flow rates were significantly higher in the 50-mg alteplase plus abciximab group versus the alteplase-only group at both 60 minutes (72% versus 43%; P=0.0009) and 90 minutes (77% versus 62%; P=0.02). The rates of major hemorrhage were 6% in patients receiving alteplase alone (n=235), 3% with abciximab alone (n=32), 10% with streptokinase plus abciximab (n=143), 7% with 50 mg of alteplase plus abciximab and low-dose heparin (n=103), and 1% with 50 mg of alteplase plus abciximab with very-low-dose heparin (n=70).Abciximab facilitates the rate and extent of thrombolysis, producing early, marked increases in TIMI 3 flow when combined with half the usual dose of alteplase. This improvement in reperfusion with alteplase occurred without an increase in the risk of major bleeding. Substantial reductions in heparin dosing may reduce the risk of bleeding even further. Modest improvements in TIMI 3 flow were seen when abciximab was combined with streptokinase, but there was an increased risk of bleeding.

In autumn 1996, shortly after the platelet glycoprotein (GP) IIb/IIIa inhibitor abciximab was approved for clinical use by the Health Protection Branch of Health Canada, seven interventional cardiologists met in a roundtable forum to review the use of abciximab in percutaneous transluminal coronary angioplasty (PTCA). While a compelling body of data was presented that argued strongly for adjunctive abciximab in conventional balloon angioplasty, the participants found in difficult to extrapolate the findings to contemporary interventional practice dominated by stent implantation. This uncertainty stemmed from the lack of clinical trials of abciximab during the stent era. Concerns were also raised that the unrestricted use of two expensive therapeutic modalities (stent implantation and GP IIb/IIIa inhibition) would place severe strains on catheterization laboratory budgets. The general consensus was that, pending the availability of further data, abciximab should probably be reserved for selected at-risk patients. This article summarized the roundtable discussions to provide cardiologists' perspectives on the use of abciximab in interventional practice. An overview of platelet physiology and the rationale for GP IIb/IIIa receptor inhibition; a summary of the results of recent randomized clinical trials that assessed the efficacy of abciximab in PTCA; an account of how stents became the most prevalent technique used in coronary intervention; a summary of the available data evaluating abciximab in conjunction with stent implantation; and a synopsis of the conference discussions are included.

To determine the effect of a moderate exercise regimen on stored iron as measured by serum ferritin in previously sedentary postmenopausal women.Randomized assignment to one of three groups: a five day/week walking group (five-day group, n = 27); a three day/week walking group (three-day group, n = 27) or a sedentary group (control group, n = 25).Community-based intervention.Women who were postmenopausal, over 50 years old, sedentary, not on hormone replacement therapy, nonsmokers, physically capable of exercising, without clinical signs of cardiovascular, pulmonary or metabolic disease, and not on medication that would affect iron metabolism. In addition, they had neither donated blood nor been transfused within the previous 12 months. All participants were screened volunteers who had responded to media advertisements. Seventy-nine participants met these criteria. Results are reported for 56 subjects (five-day group, n = 17; three-day group, n = 19; control group, n = 20) who completed the study. Their mean age was 61.3 +/- 5.8 years.The five-day group and the three-day group walked an average of 279 +/- 20 and 171 +/- 7 mins/week, respectively. Participants were counselled not to change their dietary intake.Following 24 weeks of walking, mean serum ferritin decreased significantly in the five-day group (P0.03), but not in the three-day group (P0.09) compared with controls.The extent of physical activity required to elicit a decrease in stored iron in postmenopausal women was determined. This may be clinically significant because stored iron increases significantly following menopause and excess stored iron have been cited as risk factors for coronary artery disease.

A 42-year-old man with aplastic anemia presented to hospital toxic and septic secondary to central Silastic catheter sepsis. The chronic indwelling catheter fractured during an attempt at removal and the distal remnant embolized to the right ventricular outflow tract and main pulmonary artery precipitating near cardiopulmonary collapse. The thrombosed catheter was successfully retrieved under fluoroscopy by an endovascular snare technique thus avoiding operative intervention in this immunosuppressed, thrombocytopenic and septic individual. The patient had an uneventful recovery.

This study was designed to compare the efficacy of coronary thrombolysis obtained with i.v. administration of three dose regimens of recombinant tissue plasminogen activator (rtPA). Although many studies have confirmed the efficacy of thrombolytic therapy in treatment of acute myocardial infarction, few prospective studies have been designed to determine which dose regimen optimizes the rate of coronary thrombolysis. A canine model was used. Coronary thrombosis was induced by injection of radioactive, autologous blood clots through a catheter placed in the left anterior descending coronary artery. Subsequently, 15 dogs were randomized into 3 groups of 5 dogs each. In group 1 dogs, 1.25 mg/kg of rtPA was administered i.v. as a bolus; in the group 2 dogs, 1.25 mg/kg of rtPA was administered over 60 min. The administration was "front loaded" so that 15% was administered as a bolus, 60% over 30 min, and 25% over 30 min; in group 3, 1.25 mg/kg of rtPA was divided into two i.v. boluses and administered 15 min apart. Coronary thrombolysis was assessed with a gamma camera. Despite differences in rate of administration of rtPA, at 15, 30, and 90 min after onset of treatment, extent of clot lysis was similar between groups. These results indicate that despite differences in dose regimens, rates of thrombolysis are similar when i.v. rtPA is relatively rapidly administered. Further, the similar rates of clot lysis over time between groups suggest both an effective upper limit to the dose-thrombolytic rate relationship and relatively high, sustained steady-state plasma concentrations of rtPA.

To examine the effect of a moderate exercise regimen on total serum cholesterol, triglyceride, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), body composition and cardiovascular fitness (VO2 max) in mildly hyperlipidemic women, postmenopause.Randomized assignment to walking (n = 24) or control (n = 16) groups.Community based intervention.Over 300 volunteers were screened to obtain the sample of 40 eligible women. Participants were mildly hyperlipidemic, postmenopause (mean age 62.0 +/- 5.7 years), sedentary, nonsmokers and not on hormone replacement therapy. Results are reported for the 25 subjects (15 walkers, 10 controls) who completed the study.Exercisers walked an average of 54.3 +/- 7.7 mins/day, 4.9 +/- 1.7 days/week, at an intensity of 54% maximum heart rate reserve, for six months. Participants were counselled not to change their diets.Total serum cholesterol, triglyceride, total serum cholesterol: HDL-C ratio, weight and fat mass decreased significantly in the walkers compared with the controls (P0.05), as did body mass index (P0.01). Walking resulted in a significant increase in VO2 max (P0.01). Changes in serum lipids were significantly related to changes in body fat, but not to change in aerobic fitness. There were no changes in dietary intake.A moderate intensity exercise program induces favourable alterations in total serum cholesterol and other atherogenic indices in hyperlipidemic women postmenopause, and these changes are related more to loss of body fat than to increased fitness level.

Although many studies have confirmed the efficacy of thrombolytic therapy in treatment of acute myocardial infarction, few studies have been designed to determine which dose regimen optimizes the rate of coronary thrombolysis. This study was designed to compare the efficacy of coronary thrombolysis obtained with intravenous administration of three dose regimens of recombinant tissue plasminogen activator (rtPA). The same total dose was administered as a bolus, over 30 min, or over 90 min. A canine model was employed. Coronary thrombosis was induced by injection of radioactive blood clot through a catheter placed in the left anterior descending coronary artery. Subsequently, 18 dogs were randomized into 3 groups of 6 dogs each. In group 1 dogs, 0.5 mg/kg of rtPA was administered intravenously as a bolus; in the group 2 dogs, rtPA was administered intravenously over 30 min (rtPA30); in the group 3 dogs, the drug was administered over 90 min (rtPA90). Coronary thrombolysis was assessed with a gamma camera. While at 100 min, the extent of clot lysis was similar between groups, 15 and 30 min after the start of rtPA administration, coronary thrombolysis was significantly less in the rtPA90 group. These results indicate that for a given total dose of rtPA, the rate of intravenous administration may significantly affect the rate of coronary thrombolysis.

To investigate the effect of an increase in aortic pressure combined with rapid tissue plasminogen activator infusion on hemodynamic stability and patency of the infarct-related artery in patients with acute myocardial infarction complicated by profound hypotension or cardiogenic shock.Thrombolytic therapy improves mortality in relatively stable patients with acute myocardial infarction but not in patients with cardiogenic shock. Recent canine studies have demonstrated that a moderate increase in low aortic pressure improves thrombolysis. Conceivably, then, decreased thrombolytic efficacy in cardiogenic shock is due, at least in part, to a low aortic pressure impairing delivery of the thrombolytic agent.For patients presenting within 6 h of an acute myocardial infarction complicated by profound hypotension or cardiogenic shock, an inotropic agent was rapidly administered to increase the systolic aortic pressure to approximately 110 mmHg, and 100 mg of tissue plasminogen activator was administered intravenously over 45 to 60 mins.Eight consecutive patients meeting the study criteria were treated over 18 months. In six of eight patients, the inotropic agent increased systolic blood pressure over 10 mins, from a mean of 64 +/- 12 mmHg to 102 +/- 12 mmHg. In the two patients whose blood pressure did not increase, early angiography in one demonstrated occlusion of the infarct-related artery, and both of the patients died. In the other six patients there was clinical and hemodynamic evidence of early reperfusion, and infarct-related arteries were patent on angiography. These six patients survived at least 30 days, with four having a favourable clinical outcome and two having a functional limitation due to heart failure.These results are consistent with experimental data indicating that an increase in aortic pressure combined with rapid tissue plasminogen activator infusion may increase thrombolytic efficacy when an acute myocardial infarction is complicated by profound hypotension or cardiogenic shock.

We employed a canine model of coronary thrombosis, induced by injection of radioactive blood clot, via a catheter placed in the left anterior descending coronary artery, to compare effects of intracoronary administration of recombinant tissue plasminogen activator (rtPA) and urokinase (UK) on rate and extent of coronary thrombolysis. Two doses of UK, 15,000 U/kg (UK15) and 30,000 U/kg (UK30) and two doses of rtPA, 0.25 mg/kg (rtPA.25) and 0.75 mg/kg (rtPA.75) were given. Drugs were infused over 45 min. Compared with the other regimens, rate and extent of coronary thrombolysis were significantly increased with rtPA.75. Also, despite a much higher dose of UK, coronary thrombolysis was similar with UK30 and rtPA.25. Compared with UK15, rate and extent of coronary thrombolysis were increased with rtPA.25. These results indicate that intracoronary administration of rtPA is superior to intracoronary UK in inducing thrombolysis.

We employed a canine model of coronary thrombosis, induced by injection of radioactive blood clot, via a catheter placed in the left anterior descending coronary artery, to compare effects of recombinant tissue plasminogen activator (rtPA) administered intravenously and administered directly into the coronary circulation. A control group did not receive rtPA. Compared with controls, both rtPA regimens induced coronary thrombolysis. However, compared with intravenous administration, rate and extent of coronary thrombolysis were increased with intracoronary administration. Most likely, the enhanced thrombolysis with intracoronary administration is explained by an increase in delivery of the drug to the thrombus.

The authors investigated why intrapulmonary shunt (QS/QT) increases with sodium nitroprusside (SNP) in canine oleic acid pulmonary edema. To determine the effects of flow alone on QS/QT, a peripheral arteriovenous fistula with a variable resistor was employed to increase cardiac output (Q) 26 and 52% above base line in a stepwise fashion (P less than 0.01). To examine the direct effects of SNP, distinct from changes in flow, the drug was given to produce matched increments in Q in each dog (P less than 0.01). To control for time, base-line measurements were obtained before and after each intervention, the sequence of which was alternated. At each increment in Q, SNP and the arteriovenous fistula increased QS/QT a similar amount. The mixed venous O2 tension (P-vO2) followed Q similarly in each group. Pulmonary vascular resistance (PVR) fell more (P less than 0.01) with SNP than with the arteriovenous fistula at identical Q and P-vO2. The authors conclude that, in this model, a direct pharmacological effect of SNP does not contribute to the deterioration in QS/QT. In fact, SNP exerts a pulmonary vasoactive effect that does not adversely affect gas exchange.

The "double condom sign," on a plain film of the abdomen, can be used to identify smugglers who are concealing non-opaque narcotics within the gastrointestinal tract.

A decrease in cardiac output due to increased right ventricular (RV) afterload may complicate several clinical conditions such as ARDS and pulmonary embolism (1,2).

Cerebrospinal fluid and serum penicillin levels were determined in patients with latent syphilis. Mean serum concentration one week after the third weekly dose of 2.4 million units penicillin G benzathine was 0.32 units/mL. Concurrent administration of probenecid orally produced a mean serum penicillin level of 0.41 units/mL. Doubled penicillin doses without and with daily orally administered probenecid resulted in mean serum concentrations of 0.75 and 1.00 units/mL, respectively. Two of six patients in the last group had CSF penicillin concentrations greater than 0.03 units/mL.

Pulmonary hypertension may be present in a variety of clinical conditions. For example, certain patients with the Adult Respiratory Distress Syndrome (ARDS) may develop severe pulmonary hypertension as a consequence of the underlying lung disease. The increase in right ventricular (RV) afterload may decrease cardiac output (CO) and tissue O2 delivery and may impair survival [1, 2]. In another example, short-term mortality is reported to increase when hypotension complicates pulmonary emboli. For example, mortality in patients, where the diagnosis has been confirmed angiographically is reported to be 6%, increasing to greater than 30% if hypotension develops [3].

When shock complicates an acute increase in RV afterload, initial therapy should be directed toward restoration of an adequate BP (RV coronary perfusion pressure) and CO. Current results indicate that norepinephrine, a drug with direct inotropic and pressor effects, may be an excellent agent for acute resuscitation and short-term maintenance of hemodynamic stability when frank circulatory instability complicates pulmonary embolism. Following hemodynamic stabilization, thrombolytic therapy should be initiated. Recent evidence suggests that the lytic agent can be given by bolus technique, but more work is required to determine the optimum dosing regimen. In the absence of shock, when a moderate decrease in CO complicates pulmonary embolism, isoproterenol or hydralazine may be used to improve flow. However, both of these agents may decrease systemic vascular resistance and BP. Accordingly, the latter parameter should be carefully monitored to ensure that excessive falls in BP and RV coronary perfusion pressure do not occur. Whereas in certain conditions volume expansion is appropriate therapy to increase CO, in acute pulmonary hypertension with excessive RV afterload, volume expansion may worsen RV function. Recent canine studies indicate that an increase in vascular closing pressure is the predominant mechanism explaining the increase in PAP and apparent increase in PVR complicating pulmonary embolism. Accordingly, in addition to decreasing vascular resistance, therapy to decrease RV afterload could be directed toward decreasing the vascular response producing excessive closing pressures.

Pulmonary hypertension may be present in a variety of clinical conditions. For example, certain patients with the Adult Respiratory Distress Syndrome (ARDS) may develop severe pulmonary hypertension as a consequence of the underlying lung disease [1]. The increase in right ventricular (RV) afterload may decrease cardiac output (CO) and tissue O2 delivery and may impair survival [1, 2,]. In another example, short-term mortality is reported to increase when hypotension complicates pulmonary emboli. For example, mortality in patients, where the diagnosis has been confirmed angiographically is reported to be 6%, increasing to greater than 30% if hypotension develops [3, 4].

This review considers pathophysiology and treatment of right ventricular dysfunction due to an acute increase in afterload. It focuses on cardiovascular complications and treatment of acute pulmonary embolism. However, RV function in severe ARDS is also considered. In addition, effects of pulmonary emboli and drugs on polmonary vascular characteristics per se are reviewed.

We investigated short-term hemodynamic effects of dopamine and dobutamine in eight patients with acute hypoxemic respiratory failure. We tested the hypothesis that for a similar increase in cardiac output, left ventricular filling pressure (pulmonary capillary wedge pressure [PCWP]) would increase with dopamine and decrease with dobutamine. Dopamine increased cardiac output (p less than 0.05), stroke volume (p less than 0.05), and PCWP (p less than 0.01). Cardiac output increased almost 20 percent when PCWP increased 50 percent with dopamine. In contrast, despite a mean 30 percent increase in cardiac output with dobutamine (p less than 0.01), PCWP decreased. In six of these patients, left ventricular end-diastolic volumes and end-systolic volumes were measured using scintigraphic techniques. In all patients, end-diastolic volume increased with dopamine (p less than 0.05); and in four of six, end-systolic volume increased. In contrast, with dobutamine, in five of six patients, end-diastolic volume decreased; and in all six patients, end-systolic volume decreased. There was a small increase in intrapulmonary shunt with both drugs. We conclude that if an inotropic agent is required to increase cardiac output in patients with acute hypoxemic respiratory failure, dobutamine is probably preferred over dopamine.

A decrease in cardiac output (CO) due to increased right ventricular (RV) after-load may complicate several clinical conditions such as ARDS and pulmonary embolism [1, 2].

Out of 13,455 private practice examinations performed over 6 months by 3 pediatricians and 2 general practitioners 4.2% concerned adolescents, aged 10 to 19, while they represent 16% of the population of the area. Pediatricians see less adolescents than general practitioners, and only adolescents under 14. Adolescents from workers' families seem to seek less medical advice than one would expect from their number in the population. Among the causes, respiratory infections come first, followed by requests for various medical certificates. For general practitioners, gynecologic and obstetrical problems represent one third of the reasons for consultations in girls and two thirds after 15 years.