PubMed Health⌕ Search

Biomedical subjects

P F Unger

Publications and source records attributed to P F Unger.

At least 19 recordsLinked to original sources
PubMed2000

Using clinical evaluation and lung scan to rule out suspected pulmonary embolism: Is it a valid option in patients with normal results of lower-limb venous compression ultrasonography?

BACKGROUND: In patients with a low clinical probability of pulmonary embolism (PE) and a nondiagnostic lung scan, the prevalence of PE is theoretically very low. We assessed the safety and usefulness of this association for ruling out PE. METHODS: We analyzed data from 2 consecutive cohort management studies performed in 2 university hospitals (Geneva University Hospital, Geneva, Switzerland, and Hospital Saint-Luc, Montreal, Quebec), which enrolled 1034 consecutive patients who came to the emergency department with clinically suspected PE. All patients were submitted to a sequential diagnostic protocol of lung scan, D-dimer testing, lower-limb venous compression ultrasonography (US), and pulmonary angiography in case of inconclusive results of noninvasive workup. RESULTS: The prevalence of PE was 27.6%. Empirical assessment was accurate for identifying patients with a low likelihood of PE (8.2% prevalence of PE in the low clinical probability category). One hundred eighty patients had a low clinical probability of PE and a nondiagnostic lung scan. Among these patients, US showed deep vein thrombosis in 5. Hence, PE could be ruled out by a low clinical probability, a nondiagnostic lung scan, and a normal US in 175 patients (21.5%). The 3-month thromboembolic risk in these patients was low (1.7%; 95% confidence interval, 0.4%-4.9%). CONCLUSIONS: Anticoagulant treatment could be safely withheld in patients with a low clinical probability of PE and a nondiagnostic lung scan, provided that the US is normal. This combination of findings avoided pulmonary angiography in 21.5% of patients with suspected PE in this series.

Adult↗
PubMed1999

Non-invasive diagnosis of venous thromboembolism in outpatients.

BACKGROUND: We designed a simple and integrated diagnostic algorithm for acute venous thromboembolism based on clinical probability assessment of deep-vein thrombosis (DVT) or pulmonary embolism (PE), plasma D-dimer measurement, lower-limb venous compression ultrasonography, and lung scan to reduce the need for phlebography and pulmonary angiography. METHODS: 918 consecutive patients presenting at the emergency ward of the Geneva University Hospital, Geneva, Switzerland, and Hôpital Saint-Luc, Montreal, Canada, with clinically suspected venous thromboembolism were entered into a sequential diagnostic protocol. Patients in whom venous thromboembolism was deemed absent were not given anticoagulants and were followed up for 3 months. FINDINGS: A normal D-dimer concentration (<500 microg/L by a rapid ELISA) ruled out venous thromboembolism in 286 (31%) members of the study cohort, whereas DVT by ultrasonography established the diagnosis in 157 (17%). Lung scan was diagnostic in 80 (9%) of the remaining patients. Venous thromboembolism was also deemed absent in patients with low to intermediate clinical probability of DVT and a normal venous ultrasonography (236 [26%] patients), and in patients with a low clinical probability of PE and a non-diagnostic result on lung scan (107 [12%] patients). Pulmonary angiography and phlebography were done in only 50 (5%) and 2 (<1%) of the patients, respectively. Hence, a non-invasive diagnosis was possible in 866 (94%) members of the entire cohort. The 3-month thromboembolic risk in patients not given anticoagulants, based on the results of the diagnostic protocol, was 1.8% (95% CI 0.9-3.1). INTERPRETATION: A diagnostic strategy combining clinical assessment, D-dimer, ultrasonography, and lung scan gave a non-invasive diagnosis in the vast majority of outpatients with suspected venous thromboembolism, and appeared to be safe.

Acute Disease↗
PubMed1999

Prehospital stabilization of pelvic dislocations: a new strap belt to provide temporary hemodynamic stabilization.

High energy pelvic fractures or dislocations are associated with a high rate of early complications, due to the associated intrapelvic organs. The high rate of early mortality is mostly due to the intrapelvic, retroperitoneal bleeding caused by the laceration of vascular structures located in the presacral area. External compression of the pelvic ring, using such devices as PASG or external fixators may prevent the intrapelvic collection of large hematomas by providing indirect tamponade. Unfortunately, these devices are either unavailable on the accident site, or the complexity of their handling is discouraging for the primary care-taker. A simple system of external pelvic compression which could be applied on the scene of trauma consisting of a pelvic strap-belt was therefore developed. The application of the device is easy, quick (30 seconds) and straightforward. Its use does not induce any known complications and requires minimal training. The cost and transportability of the system are further advantages. The system has already been used in 19 patients equipped on accident scene. Our first experiences using this device are reviewed.

Adult↗
PubMed1999

Acute appendicitis: influence of early pain relief on the accuracy of clinical and US findings in the decision to operate--a randomized trial.

PURPOSE: To determine the influence of early pain relief on the diagnostic performance of ultrasonography (US) and on the appropriateness of the surgical decision. MATERIALS AND METHODS: A prospective randomized, double-blind placebo-controlled trial with morphine was conducted. A visual analog scale was used to evaluate pain in 340 patients aged 16 years or older. US was performed with a standardized protocol. Diagnosis was confirmed at histologic analysis or, in the patients released without surgery, at follow-up. RESULTS: One hundred seventy-five patients were injected with morphine, and 165 were injected with the placebo. Pain relief was stronger in the morphine group. In the morphine group, US had lower (71.1%) sensitivity (difference, -9.5%; 95% CI, -18.5%, -0.5%) and higher (65.2%) specificity (difference, 11.4%; 95% CI, 1.0%, 21.8%). This group had also a higher positive predictive value (64.6%) and a lower negative predictive value (71.4%), but the differences between this group and the placebo group were not statistically significant. Among female patients, the decision to operate was appropriate more often in the morphine group (75.8%), but the difference between this group and the placebo group was not statistically significant (5.1%; 95% CI, -7.4%, 17.6%). In male patients and overall, opiate analgesia did not influence the appropriateness of the decision. The appropriateness to discharge patients without surgery was 100% in all groups. CONCLUSION: Morphine does not improve US-based diagnosis of appendicitis.

Abdominal Pain↗
PubMed1998

Do physicians modify their prehospital management of patients in response to a public campaign on chest pain?

The goals of this study were to analyze the impact of a public campaign on chest pain on physicians involved in the prehospital care of patients with this symptom, in terms of physician delay, rates of immediate hospitalization, and of transportation by ambulance. Prehospital delays and decisions for all 866 patients with chest pain managed by the community and generalist physicians or by emergency physicians, who presented to the emergency department of a teaching hospital during the 12 months of the campaign, were compared with those of all 749 patients with similar presentations during the 12 months before it. When community and generalist physicians were involved, median (110 minutes) physician delay did not decrease during the campaign, whereas it decreased from 65 to 56 minutes (p <0.003) when emergency physicians were involved. Rates of immediate hospitalization (73%) and of transportation by ambulance (47%) of patients managed by community and generalist physicians were unaffected by the campaign, whereas they increased from 96% and 89%, respectively, to 98% (p = 0.09) and 94% (p <0.02) when emergency physicians were involved. Similar observations were made in patients with confirmed acute myocardial infarction and unstable angina and remained highly significant after adjustment for differences in clinical characteristics. Thus, community and generalist physicians did not significantly modify their prehospital management of patients with chest pain despite a public campaign. To be successful, guidelines on the matter have to be developed with the active participation of these physicians.

Aged↗
PubMed1998

Diagnostic accuracy of Doppler-echocardiography in unselected patients with suspected pulmonary embolism.

This study investigates the diagnostic value of echocardiography in patients with suspected pulmonary embolism. Doppler-echocardiography was performed in fifty consecutive patients, predominantly presenting in the emergency ward, with clinically suspected pulmonary embolism. Patients were classified as having or not pulmonary embolism by a sequential non-invasive strategy including lung scan, D-dimer measurement and lower limb venous compression ultrasonography, pulmonary angiography being performed in case of an inconclusive non-invasive work-up. The prevalence of pulmonary embolism was 36% (18 of 50 patients). Right ventricular dilatation on 2-D echocardiography associated to a tricuspid regurgitation velocity > or =2.7 m/s, corresponding to a pulmonary systolic pressure > or =39 mmHg, were present in 12 of the 18 patients (67%) with and in two of the 32 patients (6.3%) without pulmonary embolism. They were, however, absent in five of the 18 patients (28%), in whom the definite diagnosis of pulmonary embolism was made. The combination of these both echocardiographic criteria yielded a sensitivity of 67% and a specificity of 94%, positive predictive value was 86% and negative predictive value was 83%. The diagnostic performance of these two combined echocardiographic criteria, when present, permitted to reach in patients with a high clinical pre-test probability of pulmonary embolism the post-test probability values above 90%. On the other hand, the absence of these two Doppler-echocardiographic criteria did not allow to exclude pulmonary embolism, except in presence of a low pre-test probability. The findings of our study show that Doppler-echocardiography in patients with high clinical suspicion of pulmonary embolism may represent a potentially useful screening technique for the diagnosis of the disease permitting prompt initiation of treatment. However, the method does not allow to exclude pulmonary embolism in all patients with intermediate or high clinical suspicion of the disease.

Dilatation, Pathologic↗
PubMed1998

Predictors of inappropriate hospital days in a department of internal medicine.

BACKGROUND: This study aimed to identify predictors of inappropriate hospital days in a department of internal medicine, as a basis for quality improvement interventions. METHODS: The appropriateness of 5665 hospital days contributed by 500 patients admitted to the Department of Internal Medicine, Geneva University Hospitals, Switzerland, was assessed by means of the Appropriateness Evaluation Protocol. Predictor variables included patient's age and sex, manner of admission and discharge, and characteristics of hospital days (weekend, holiday, sequence). RESULTS: Overall, 15% of hospital admissions and 28% of hospital days were rated as inappropriate. In multivariate models, inappropriate hospital days were more frequent among patients whose admission was inappropriate (odds ratio [OR] = 5.3, 95% CI: 3.1-8.4) and among older patients (80-95 years: OR = 3.6, 95% CI: 1.7-7.0, versus <50 years). The likelihood of inappropriateness also increased with each subsequent hospital day, culminating on the day of discharge, regardless of the total length of stay. CONCLUSIONS: This study identified both the admission and the discharge processes as important sources of inappropriate hospital use in a department of internal medicine. The oldest patients were also at high risk of remaining in the hospital inappropriately. Surprisingly, long hospital stays did not generate a higher proportion of inappropriate days than short hospital stays. This information proved useful in developing interventions to improve the hospitalization process.

Adolescent↗
PubMed1997

Cost-effectiveness of noninvasive diagnostic aids in suspected pulmonary embolism.

BACKGROUND: Noninvasive instruments such as plasma D-dimer measurement (DD) and lower-limb compression ultrasonography (US) are being increasingly advocated to reduce the number of necessary angiograms in patients having suspected pulmonary embolism (PE) and a nondiagnostic lung scan. We therefore designed a decision analysis model (1) to evaluate the cost-effectiveness of combining these noninvasive diagnostic aids with lung scan and angiography in the diagnosis of PE and (2) to determine the optimal sequence and combination of tests taking into account the clinical probability of PE. METHODS: We performed a cost-effectiveness analysis based on literature data, including data from a management study in our institution. Six diagnostic strategies were compared with the reference, ie, lung scan followed when nondiagnostic (low or intermediate probability) by angiography. In all strategies, PE was ruled out by a normal or near-normal scan, a negative DD (plasma level below 500 micrograms/L), or a negative angiogram. Pulmonary embolism was diagnosed and anticoagulant treatment was undertaken in the presence of a high-probability lung scan, deep vein thrombosis showed by US, or a positive angiogram. In case of a nondiagnostic scan (low or intermediate probability), patients could be either treated or not treated, or undergo other tests, according to the selected strategy. RESULTS: Under baseline conditions (prevalence of PE, 35%), strategies combining DD and US with lung scan, angiography being done only in case of an inconclusive noninvasive workup (DD level > 500 micrograms/L, normal US, and nondiagnostic lung scan), were most cost-effective. This approach yielded a 9% incremental cost reduction and a 37% to 47% decrease in the number of necessary angiograms compared with the reference strategy (scan +/- angiography). For patients with a low clinical probability of PE (< or = 20%), withholding treatment from those with a low-probability lung scan without performing an angiogram proved safe and highly cost-effective (30% cost reduction), provided US showed no deep vein thrombosis. CONCLUSION: The DD test and US are cost-effective in the diagnostic workup of PE, whether performed after or before lung scan, thus allowing centers devoid of lung scanning and/or angiography facilities to screen patients with suspected PE and avoid costly referrals. In patients with a low clinical probability, a low-probability lung scan, and a normal US, treatment may be withheld without resorting to angiography.

Algorithms↗
PubMed1997

[Thrombolysis in acute myocardial infarct in everyday clinical practice].

We prospectively included in a database all thrombolyzed acute transmural myocardial infarction patients admitted to our hospital from November 1986 to September 1995. Six hundred and twenty-seven patients (497 males) with a mean age of 61 +/- 12 years (range 26-88 years) were included. 87% were having their first acute myocardial infarction. Different thrombolytic regimens were applied in the emergency room but the vast majority (92%) received t-PA. The median delay between the onset of pain and admission was 2 h 0 min (10 min-22 h). The median admission to treatment time was 40 min (5 min-6 h 20 min). The latter has been shortened (median 55 min from 1986 to 1989 versus 35 min from 1990 to 1995, p < 0.05) during the study period. The rate of intracerebral hemorrhage was 2.4% (confidence interval 1.1-3.5%) and no significant predictor could be found, although patients with cerebral bleeding tended to be slightly older (66 +/- 9 years vs 61 +/- 13 years, p = ns). The rate of false diagnosis was only 4.6%, even when patients with a final diagnosis of unstable angina and/or aborted acute myocardial infarction were included. The in-hospital mortality was 8.8%, a rate similar to those reported in the literature. Using multivariate analysis, negative prognostic factors were higher age (p < 0.001), advanced Killip class at admission (p < 0.001) and elevated peak CPK levels (p < 0.001). These results confirm that thrombolysis for acute myocardial infarction in the emergency room can be done with a short admission-to-treatment time and with an acceptably low rate of false diagnosis. However, our intracerebral hemorrhage rate was clearly higher than generally reported in the literature and may be explained by a different patient selection from that in large randomized studies.

Adult↗
PubMed1997

Risk factors for a medically inappropriate admission to a Department of Internal Medicine.

OBJECTIVE: To identify patient- and admission-related risk factors for a medically inappropriate admission to a department of internal medicine. METHODS: Cross-sectional study of a systematic sample of 500 admissions to the department of internal medicine of an urban teaching hospital. The appropriateness of each admission and reasons for inappropriate admissions were assessed using the Appropriateness Evaluation Protocol. Risk factors included the time (day of week and holidays) and manner (through emergency department or direct admission) of admission, patient age and sex, health status of patient and spouse, living arrangements, formal home care services, and informal support from family or friends. RESULTS: Overall, 76 (15.2%) hospital admissions were rated as medically inappropriate by the Appropriateness Evaluation Protocol. In multivariate analysis, the likelihood of an inappropriate admission was increased by better physical functioning of the patient (odds ratio [OR], 1.5; 95% confidence interval [CI], 1.1-2.1 [for 1 SD in Physical Functioning scores]), lower mental health status of the patient's spouse (OR, 2.6; 95% CI, 1.3-5.6), receipt of informal help from family or friends (OR, 3.3; 95% CI, 1.5-7.2), and hospitalization by one's physician (OR, 3.6; 95% CI, 1.7-7.5). Receiving formal adult home care was not associated with inappropriateness of hospitalization. CONCLUSIONS: Inappropriate admissions to internal medicine wards are determined by a mix of factors, including the patient's health and social environment. In addition, the private practitioners' discretionary ability to hospitalize their patients directly may also favor medically inappropriate admissions.

Adolescent↗
PubMed1997

C-reactive protein as a marker for acute coronary syndromes.

BACKGROUND: For several years, acute coronary syndromes have been perceived as causing the most hospital admissions, and even hospital mortality. The syndrome of unstable angina frequently progresses to acute myocardial infarction but its pathogenesis is poorly understood, and prognosis determination is still problematic. We tested the hypothesis that measurement of the C-reactive protein in patients admitted for chest pain could be a marker for acute coronary syndromes. METHODS AND RESULTS: We studied 110 patients admitted with suspected ischaemic heart disease, but without elevated serum creatine-kinase levels at the time of hospital admission. Patients were subsequently divided into two groups based on their final diagnosis: group 1 comprised patients with unstable angina; group 2 patients with acute myocardial infarction. We measured the C-reactive protein at the time of hospital admission. The concentration of C-reactive protein was elevated in 59% of the patients with a final diagnosis of acute myocardial infarction, and in 5% of the patients with a final diagnosis of unstable angina, (P < 0.001). CONCLUSION: This study indicates that C-reactive protein levels measured at the time of admission in patients with suspected ischaemic heart disease could be a marker for acute coronary syndromes, and helpful in identifying patients at high risk for acute myocardial infarction. Measurement of C-reactive protein may have practical clinical significance in the management of patients hospitalized for suspected acute coronary syndromes.

Acute Disease↗
PubMed1997

D-dimer testing for suspected pulmonary embolism in outpatients.

The plasma level of D-dimer, a fibrin degradation product (FDP), is nearly always increased in the presence of acute pulmonary embolism (PE). Hence, a normal D-dimer level (below a cutoff value of 500 micrograms/L by enzyme-linked immunosorbent assay [ELISA]) may allow the exclusion of PE. To assess the negative predictive value of a D-dimer concentration below 500 micrograms/L in outpatients with suspected PE, and the safety of withholding anticoagulant treatment from such patients, we performed D-dimer assays, lower limb venous compression ultrasonography, and lung scans in 671 consecutive outpatients presenting in the Emergency Center of the Geneva University Hospital with suspected PE. Pulmonary angiography was reserved for patients with an inconclusive noninvasive workup. Patients with a normal D-dimer concentration were discharged without anticoagulant treatment and followed for 3 mo. The prevalence of PE was 29%, and D-dimer (using a cutoff of 500 micrograms/L) had a diagnostic sensitivity for PE of 99.5%. Overall diagnostic specificity of D-dimer was 41%, but it was lower among older patients. Of the 198 patients with a D-dimer concentration below the cutoff value, 196 were free of PE, one had a PE, and one had incomplete information because of loss to follow-up. Thus, the negative predictive value of D-dimer concentration fell between 197 of 198 and 196 of 198 cases of PE (99% [95% CI: 96.4 to 99.9]). Using a cutoff value of 4,000 micrograms/L, the overall specificity of D-dimer concentration for PE was 93.1%. In conclusion, a plasma D-dimer concentration below 500 micrograms/L allows the exclusion of PE in 29% of outpatients suspected of having PE. Withholding anticoagulation from such patients is associated with a conservative 1% risk of thromboembolic events during follow-up.

Adolescent↗
PubMed1996

Impact of a public campaign on pre-hospital delay in patients reporting chest pain.

OBJECTIVE: To decrease pre-hospital delay in patients with chest pain. DESIGN: Population based, prospective observational study. SETTING: A province of Switzerland with 380000 inhabitants. SUBJECTS: All 1337 patients who presented with chest pain to the emergency department of the Hôpital Cantonal Universitaire of Geneva during the 12 months of a multimedia public campaign, and the 1140 patients who came with similar symptoms during the 12 months before the campaign started. MAIN OUTCOME MEASURES: Pre-hospital time delay and number of patients admitted to the hospital for acute myocardial infarction (AMI) and unstable angina. RESULTS: Mean pre-hospital delay decreased from 7h 50 min before the campaign to 4 h 54 min during it, and median delay from 180 min to 155 min (P < 0.001). For patients with a final diagnosis of AMI, mean delay decreased from 9 h 10 min to 5 h 10 min and median delay from 195 min to 155 min (P < 0.002). Emergency department visits per week for AMI and unstable angina increased from 11.2 before the campaign to 13.2 during it (P < 0.02), with an increase to 27 (P < 0.01) during the first week of the campaign; visits per week for non-cardiac chest pain increased from 7.6 to 8.1 (P = NS) during the campaign, with an increase to 17 (P < 0.05) during its first week. CONCLUSIONS: Public campaigns may significantly reduce pre-hospital delay in patients with chest pain. Despite transient increases in emergency department visits for non-cardiac chest pain, such campaigns may significantly increase hospital visits for AMI and unstable angina and thus be cost effective.

Angina, Unstable↗
PubMed1995

[Syncope: "missed death" or triviality?].

Syncope is a common clinical problem defined as a transient loss of consciousness and postural tone with spontaneous recovery. Etiology is extremely diverse. In a great majority of cases the outcome is favorable; however, if a syncope is of cardiac origin, the risk of subsequent sudden death is relatively high. This fact implies an approach to the evaluation of the possible cause of syncope to minimize the risk of an important misdiagnosed problem. The etiology of syncope is generally found by careful history, clinical examination and an ECG. The strategy to use further investigations is discussed and provides a framework for approaching the final diagnosis prior to initiation of specific treatment.

Adult↗
PubMed1995

Influence of white cell count on surgical decision making in patients with abdominal pain in the right lower quadrant.

OBJECTIVE: To evaluate the influence of white cell count (WCC) on the decision to operate on patients with right lower abdominal pain. DESIGN: Open study. SETTING: University hospital, Switzerland. SUBJECTS: 221 adult patients admitted to emergency department with right lower abdominal pain. INTERVENTIONS: Surgeons were unaware of the WCC until after they had initially decided whether to remove the appendix. They were told the result and asked if it would influence their final decision. MAIN OUTCOME MEASURE: Whether surgeons changed their minds about operation when told the initial WCC. RESULTS: 112 Patients (51 men and 61 women) were operated on, of which 44 men (52%) and 42 women (31%) had histologically confirmed appendicitis. The decision to operate was influenced by the initial WCC in only 6 patients (3%, 95% confidence interval (CI) 0.6 to 4.9%). At follow up after 30 days the change of decision in the 6 patients had been correct in 5. CONCLUSION: The WCC did not significantly influence surgical decision-making in the group of patients who were suspected of having acute appendicitis.

Abdominal Pain↗
PubMed1994

Applicability of decision analysis to everyday clinical practice: a controlled feasibility trial.

OBJECTIVE: To determine whether decision analysis is applicable to routine management of suspected pulmonary embolism in an emergency care setting. DESIGN: Controlled feasibility trial. SETTING: Emergency center of a university hospital. PATIENTS: Outpatients (n = 84) admitted with clinical and scintigraphic evidence of pulmonary embolism. INTERVENTIONS: Patients were treated either with the usual clinical work-up for pulmonary embolism (control group) or using a decision analysis model with three options: no action: angiography followed by treatment if positive; treatment without angiography. RESULTS: All six senior residents in the decision analysis group agreed to fully participate for the 16 months of the study. Summarizing the decision analysis model in a graph was critical to obtain acceptance from all the physicians. Decision analysis (n = 43) and control (n = 41) patients underwent similar numbers of angiographies. However, angiographies for patients who had intermediate clinical probabilities of pulmonary embolism, between 25 and 75%, were more frequent in the decision analysis group (9/13 = 69%) than in the control group (7/20 = 35%). Agreement between clinical probability and lung-scan result was stronger in the decision analysis group. CONCLUSIONS: Decision analysis was successfully used to manage all patients suspected of having pulmonary embolism admitted to an emergency center during the 16-month trial. There was no insuperable obstacle to acceptance of clinical decision analysis by the physicians. Decision analysis may have resulted in a better discrimination between low and intermediate clinical probabilities of pulmonary embolism.

Adult↗