Biomedical subjects

J M Lohr

Publications and source records attributed to J M Lohr.

At least 19 recordsLinked to original sources

PubMed1999

Visual avoidance in specific phobia.

Cognitive models of anxiety postulate that fear and anxiety serve as programs for avoidance of threat-relevant stimuli. We hypothesized that exposure to phobia-relevant stimuli would lead to visual avoidance in specific phobics. Spider phobic, blood-injection-injury phobic, and nonphobic participants were asked to view spider, injection, and neutral photographs through a three-channel tachistoscope that measured viewing time for each picture. Despite experimenter instructions to study the pictures carefully for a subsequent recognition test, phobic subjects showed decreased viewing times for threat-relevant pictures as compared to neutral pictures. Results are discussed in terms of cognitive models of anxiety disorders and implications for exposure-based therapies.

Adolescent↗

PubMed1999

Exposure to disgust-evoking imagery and information processing biases in blood-injection-injury phobia.

Biased processing of threat-relevant information is a central construct among contemporary theories of anxiety. However, biases in attentional and memory processes have not been systematically investigated in blood-injection-injury (BII) phobia. Theory has suggested that disgust rather than fear characterizes BII phobia and may mediate processing biases differently. We investigated the effects of a disgust mood induction on attention and memory in BII phobic and nonphobic participants. The Stroop task failed to demonstrate an attentional bias toward medical and disgust words, even under conditions of disgust provocation. However, an implicit memory task showed that BII phobics completed more medical and disgust word stems than nonphobics. These results suggest that BII phobia may be characterized by a similar implicit memory, but not an attentional, bias found in other anxiety disorders. As such, information processing in BII phobia may be qualitatively different from other anxiety disorders. Implications for further research regarding information processing biases in BII phobia are discussed.

Adolescent↗

PubMed1999

Evaluation of lidocaine as an analgesic when added to hypertonic saline for sclerotherapy.

PURPOSE: The efficacy of sclerosing agents for the treatment of telangiectasias and reticular veins is well established. The injection of these agents is often associated with pain, and it is not uncommon for sclerotherapists to include lidocaine with the sclerosants in an attempt to reduce the pain associated with treatment. However, there are concerns that this may reduce the overall efficacy of the treatment because of dilution of the sclerosant. Patient comfort and overall outcome associated with treatment using HS with lidocaine (LIDO) versus that using HS alone was compared. METHODS: Forty-two patients were prospectively entered into the study and randomized blindly to sclerotherapy with 23.4% HS or 19% LIDO. Study subjects and treating physicians were blinded to the injection solution used. Injection sites were chosen for veins ranging in size from 0.1 to 3 mm. Photographs of the area to be treated were taken, and the patients rated their pain. They were then observed at regular intervals for four months, and clinical data was collected. Thirty-five subjects completed the full follow-up period, and photographs of the injected area were taken again. Three investigators blinded to the treatment assignment then evaluated the photographs and scored the treatment efficacy according to a standardized system. RESULTS: In the HS group, 61.9% (13 of 21) patients rated their pain as none or mild, whereas 90.5% (19 of 21) of patients in the LIDO group had no or mild discomfort. This difference is significant, with a P value of.034. There was no difference in the overall efficacy of treatment between the two groups. The groups had similar rates of vein thrombosis and skin necrosis. CONCLUSION: Although lidocaine is often used with sclerosing agents, there are no previous reports in the literature to evaluate its effectiveness in reducing the pain experienced by the patient. In this study, patients receiving LIDO experienced significantly less discomfort at the time of injection than patients who received HS alone. There were no differences in the effectiveness of treatment or in the incidence of complications between the two groups.

Analgesics↗

PubMed1997

Endovascular stent infection with delayed bacterial challenge.

BACKGROUND: Reports of endovascular stent infection have recently been described. The purpose of this study was to determine if intravascular metallic stents in a swine model could become infected following a bacterial challenge given remote from the time of stent placement. METHODS: Balloon expandable metallic stents (Palmaz) were implanted in the iliac arteries of 14 swine. An angioplasty, without stent placement, was also performed in the contralateral iliac artery. An intravenous bacterial challenge with Staphylococcus aureus was given 4 weeks after stent placement. Euthanasia was performed 72 hours after the bacterial challenge. At the time of euthanasia, the iliac artery/stent complex and the contralateral angioplastied iliac artery were harvested and sent for microbiologic and pathologic analysis. RESULTS: Seven of the 14 stent/artery complexes were culture positive for S aureus whereas only one of the 14 angioplastied arteries was positive for S aureus (P = 0.03). On histologic examination, 6 of the 14 stent/artery complexes had evidence of acute inflammatory changes in the arterial wall. This compares with only 1 of 14 angioplastied arteries having evidence of inflammatory infiltrate in the arterial wall (P = 0.07). All 6 of the stent/artery complexes with inflammatory infiltrate were culture positive. CONCLUSION: In the swine model, intravascular metallic stents have the potential to become infected when a bacterial challenge is given 4 weeks after stent placement. Further studies evaluating the incidence of stent infections in humans are needed.

Angioplasty↗

PubMed1997

Disgust and disgust sensitivity in blood-injection-injury and spider phobia.

Blood-injection-injury (BII) phobics and spider phobics show markedly different cognitive, psychophysiological, and motoric reactions to activating stimuli. These observations have led theorists to question whether the emotion of fear mediates both phobias. The present study examined the role of disgust and disgust sensitivity in these subtypes of specific phobia. BII phobics, spider phobics, and nonphobics completed questionnaires and rated pictures of specific objects on fear and disgust scales. Questionnaire data indicated that phobic participants were higher than nonphobics on fear, and also on disgust sensitivity. The reaction of BII phobics to pictures of medical stimuli was one of disgust, rather than fear. The reaction of spider phobics to pictures of spiders was a combination of fear and disgust, though fear appeared to predominate. Results are discussed in view of current theories of emotional factors in specific phobia.

Adolescent↗

PubMed1996

Analysis of autogenous vein femoral-infrapopliteal bypass for limb salvage in the elderly.

The hypothesis that older patients undergoing femoral-infrapopliteal bypass have a similar outcome as a matched younger group of patients undergoing the same operation was tested. Seventy-six femoral-infrapopliteal autogenous saphenous vein bypasses for critical limb ischemia were performed from 1985 to 1990. By using the life-table method, the primary and secondary patency, limb salvage and survival rates are analyzed and compared for older and younger age groups. Forty cases (53%) were performed in an elderly group, defined as age 70 or older. At 4 years, there was no significant difference between age groups in limb salvage and patency rates. However, operative mortality for the older age group was 12%, compared with 0% in the younger group (P = 0.0004). Thus, femoral-infrapopliteal autogenous vein bypass can be performed with comparable limb salvage and patency rates for an older age group, but the risk of operative mortality appears to be increased with age.

Adult↗

PubMed1996

Infection of endovascular stents in a swine model.

BACKGROUND: Percutaneous balloon angioplasty with intravascular metallic stent placement has rapidly gained popularity for the treatment of arterial occlusive disease. Although the incidence of vascular prosthetic infection is well described, the risk of infection following metallic stent placement is unknown. The purpose of this study was to determine if intravascular metallic stents could become infected following systemic bacterial challenge. METHODS: Balloon expandable metallic stents were implanted in the iliac arteries of 10 swine following balloon catheter angioplasty. A second angioplasty, without stent placement, was also performed in the contralateral iliac artery. A bacterial challenge with Staphylococcus aureus was then infused into the aorta immediately after stent placement. Group 1 (n = 5) was killed at 72 hours, and group 2 (n = 5) at 3 weeks. A third group (n = 5) underwent stent placement without bacterial challenge and was killed at 3 weeks. At the time of death, the stents were cultured, and both iliac arteries were submitted for pathologic examination. Arterial patency and evidence of systemic infection were also assessed. RESULTS: In the animals sacrificed at 72 hours (group 1), 80% had stent cultures with significant growth of S aureus; while at 3 weeks (group 2), 60% of cultures were positive. Of the stents placed without bacterial challenge (group 3), none had a positive culture at 3 weeks. In group 2, 40% of the stented arteries remained patent, while 100% of group 3 remained patent until sacrifice at 3 weeks. All of the stented arteries which were patent at 3 weeks were culture negative, while all those which were thrombosed were culture positive for S aureus. When compared to angioplasty alone, the presence of a stent was strongly associated with pathologic evidence of inflammation [93% versus 7%]. The quality of inflammation in the stented groups also differed. Ninety percent of the stented arteries in groups 1 and 2 had acute inflammation, compared to only 20% in group 3. The remainder of the stented arteries in group 3 had chronic inflammation or were normal. CONCLUSION: In the swine model, intravascular metallic stents have the potential to become infected. This is associated with acute inflammation of the arterial wall and vessel thrombosis. Further studies evaluating the incidence of stent infections in humans are needed.

Angioplasty, Balloon↗

PubMed1996

Lessons learned from the DIASTAT vascular access graft.

BACKGROUND: The vascular community continues to search for the ideal vascular access graft that will allow early cannulation and avoid temporary central venous catheters. METHODS: This is a review of the Cranley Surgical Associates' experience with the use of the Gore-Tex DIASTAT (W.L. Gore & Associates, Inc., Flagstaff, Arizona) vascular access graft in 20 patients compared with 20 control patients matched for age, sex and risk factors. RESULTS: Although the DIASTAT graft is touted for early accessibility and decreased need for central venous access, that was not found to be the case as 14 patients in the DIASTAT group received temporary access catheters. There was significantly more edema in the DIASTAT patients (P = 0.0048). Comparing the time to the first thrombosis or to revision revealed an average of 18 weeks for the DIASTAT group and 56 weeks for the control group. The length of time to thrombosis or revision was significantly longer in the control group (P = 0.0058). Comparison of the number of weeks of function and serviceability of the grafts revealed the average DIASTAT graft functioned for 34 weeks and that of the control group for an average of 70 weeks (P = 0.0131). Comparison of the two groups showed a significant increase in early thrombotic events (< 90 days) in the DIASTAT grafts (P = 0.0013). CONCLUSIONS: The DIASTAT vascular access graft does not appear to be the ideal hemodialysis access graft.

Adult↗

PubMed1996

Tricuspid insufficiency after intracardiac migration of a Greenfield filter: case report and review of the literature.

We report the only known case of intracardiac vena cava filter migration resulting in valvular dysfunction. Echocardiographic evaluation documented the filter stenting open the tricuspid valve, with wide-open regurgitation. This case, as well as 22 cases of filter migration reported in the English literature, are used as a background to review prevention and treatment strategies.

Aged↗

PubMed1996

Venous thrombotic complications of pregnancy.

A total 30,040 pregnancies were reviewed at one institution over 5 years to determine the incidence of venous thrombotic complications. Thirty-one patients experienced such complications related to pregnancy (incidence 0.1%); 13 had deep venous thrombosis and 14 had superficial venous thrombophlebitis diagnosed by duplex ultrasound. Four had pelvic vein thrombophlebitis diagnosed by computed tomography scan; three patients (one from each group) sustained a non-fatal pulmonary embolus. Of those with deep venous thrombosis, 10 (77%) were left-sided, and three (23%) were right-sided. Three had a prior history of deep venous thrombosis and one of pulmonary embolism. Of those with superficial venous thrombophlebitis, seven (50%) were left-sided, six (43%) were right-sided, and one (7%) was bilateral. Most with deep venous thrombosis presented later in pregnancy; three in the first trimester, two in the second, three in the third, and five early postpartum. Most (10/14) with superficial venous thrombophlebitis presented within 48 hours of delivery. Distribution of thrombi in those with deep venous thrombosis was compared with 643 non-pregnant women with a similar condition. A pattern of proximal involvement on the left was found, with left common femoral vein (54% versus 28%, P = 0.03) and superficial femoral vein (62% versus 26%, P = 0.006) more often involved in pregnant patients. The average number of vein segments involved was greater on the left than the right (5.3 versus 3.7). Symptoms of chronic venous insufficiency developed in three with deep venous thrombosis (25%) and in three with superficial venous thrombophlebitis (27%). None had recurrence of deep venous thrombosis. It is concluded that venous thrombotic complications associated with pregnancy are not necessarily benign, with the risk of pulmonary embolism and chronic venous insufficiency not limited to patients with deep venous thrombosis only.

Adult↗

PubMed1996

A large sample empirical typology of male spouse abusers and its relationship to dimensions of abuse.

A number of studies have described typologies of domestically violent men. Holtzworth-Munroe and Stuart (1994) recently proposed a theoretical model for predicting violence severity and generality from personality "type." The present study, using data from 833 identified abusive men, tested the model. Personality types were determined from cluster analysis of data from the Millon Clinical Multiaxial Inventory, and resulted in a three-cluster solution consistent with the Holtzworth-Munroe and Stuart model. The three main clusters included nonpathological, antisocial, and passive aggressive-dependent groups. Three other, smaller types were also identified. Multivariate and chi-square analyses comparing the main clusters on other variables generally supported the Holtzworth-Munroe and Stuart model. Nonpathological men had the lowest maximum violence and frequency. They restricted their violence primarily to intimate relationships and had the fewest police contacts. Antisocial and passive aggressive-dependent men did not differ in maximum violence, but antisocial men were the most generally violent and had the most police contacts. Passive aggressive-dependent men had the highest frequency of violence. Clinical, theoretical and methodological implications are discussed.

Adult↗

PubMed1995

Eye movement desensitization of medical phobias: two case studies.

We treated two medical phobic subjects with eye movement desensitization (EMD). Using detailed images of fear-related events, the treatment design conformed to an additive, within-series phase change to examine enduring effects. Results indicated that both subjects' verbal reports of fear decreased substantially using the EMD procedure. There were no consistent changes in heart rate. Similarly, self-reported fear toward a simulated blood draw decreased, but heart rate and blood pressure did not. Data for a number of standardized measures of medical fear indicated posttreatment reduction for both subjects. Anecdotal reports of medical procedures revealed limited generalization of treatment effects.

Adult↗

PubMed1995

The empirical status of the clinical application of eye movement desensitization and reprocessing.

The published reports of the clinical application of eye movement desensitization and reprocessing (EMDR) are reviewed in terms of empirical validity. Case studies, single-subject experiments and group design experiments on clinical problems are evaluated for the effectiveness of the protocol, component effects, comparative effects and treatment fidelity. Classification of disorders and measurement issues are addressed. The protocol frequently reduces verbal report and independent observer ratings of distress--strikingly in some instances. Psychophysiologic measures show little effect of treatment. There is little empirical evidence to indicate the effect of treatment on motoric or behavioral indices. Eye movements do not appear to be an essential component of treatment, and there have been no substantial comparisons with other treatments. No studies have adequately controlled for nonspecific (placebo) effects of treatment. Suggestions are made for applying improved methodological controls for future applications of EMDR to clinical disorders.

Adult↗

PubMed1995

Effects of completion angiography on the outcome of carotid endarterectomy.

The carotid endarterectomy results of a single surgeon were analyzed over an 8-year period to determine how routine completion angiography affected endarterectomy outcome. Completion angiography was performed in 80% of cases. A total of 145 patients (86%) were symptomatic while 23 (14%) were symptom-free. Of 131 completion angiographies performed, 94 were interpreted as normal and 37 abnormal. The arteries were reopened in 23 patients with abnormal results. In the 14 patients with abnormal angiograms who were not reopened, two showed no flow into the internal carotid artery and the vessels were ligated. The remaining 12 patients had abnormalities in the external carotid artery or normal Doppler signals along the common carotid artery and internal carotid artery segments. Among the 37 patients with abnormal angiograms, arteries were re-explored in four; there were no neurologic complications. In the entire group, there were three mortalities, one stroke, one transient ischemic attack, two wound complications, four myocardial infarctions, two occurrences of cerebral edema, two pneumonias and nine transient local nerve injuries. Completion angiography has allowed an improved technique while also enhancing the ability to identify technical problems during surgery without increasing morbidity. These results support the use of intraoperative completion angiography to evaluate carotid endarterectomy sites.

Aged↗

PubMed1995

Allastair B. Karmody Award. Calf vein thrombi are not a benign finding.

BACKGROUND: Currently, there is no consensus in the literature regarding which patients with calf vein thrombi are at high risk for proximal propagation. This study examined patients with isolated calf vein thrombi with serial duplex scans in order to identify risk factors that would predict outcome. PATIENTS AND METHODS: Between May 1989 and November 1994, 288 patients were identified with isolated calf vein thrombi. One hundred ninety-two of them had sequential scans performed. RESULTS: Fifty-three (28%) of the 192 patients had propagation of their initial thrombi. The most proximal level of propagation was the popliteal vein in 11 patients, the superficial femoral vein in 5, the common femoral vein in 5, adjacent tibial or soleal veins in 24, adjacent soleal veins alone in 7, and the lesser saphenous vein in 1. Three patients whose thrombi propagated had free-floating thrombus tips in the large veins of their thighs. Symptoms, prophylaxis, and risk factor analysis comparing those patients whose thrombi propagated to those whose thrombi did not found no statistically significant prognostic value. Single or multiple calf vein thrombi did not predict propagation. Of the 23 patients treated with heparin, only 3 had thrombus propagation. None of these reached the level of the knee (including popliteal vein). CONCLUSIONS: The natural history of distal lower extremity thrombosis does not appear to be as benign as previously believed.

Female↗

PubMed1995

Vascular laboratory personnel on-call: effect on patient management.

PURPOSE: A prospective study was undertaken of all vascular laboratory tests performed by the "on-call" technologist during a 3-year time period. METHODS: Technologists take call on a rotating basis. All patients evaluated had symptoms. History and risk factor data were collected at the time of patient encounter. RESULTS: Studies were initiated from the emergency department 56% of the time, from inpatient examinations 33% of the time, and from outpatient examinations 11% of the time. Ninety percent (n = 440) of the studies obtained were venous duplex scans (VDS). Fifty-eight percent (257 of 440) of the studies were performed on weekends. Thirty-two percent of the studies resulted in admission of the patient. Of the 440 VDS obtained, 51% (224 of 440) identified some type of disease. Acute deep venous thrombosis (DVT) was diagnosed in 15% (67 of 440), acute superficial venous thrombosis (SVT) in 4% (17 of 440), acute DVT and SVT in 7% (31 of 440), chronic DVT in 4% (17 of 440), chronic SVT in 4% (16 of 440), and chronic DVT and SVT in 1% (3 of 440); 2% (9 of 440) of the DVTs were of indeterminate age. Other diseases were identified in 22% (95 of 440), including popliteal cysts, inguinal lymphadenopathy, and soft tissue edema. CONCLUSIONS: Having an "on-call" vascular technologist has allowed patients with acute venous thrombosis to be triaged and admitted, if necessary, in a timely fashion. Those patients who have symptoms and a negative VDS result are able to avoid unnecessary hospitalization and treatment. The expense of this service is easily justified by the savings of unnecessary hospital days.

Chi-Square Distribution↗

PubMed1995

Venous hemodynamic changes during laparoscopic cholecystectomy.

Virchow's triad of venous stasis, vessel wall damage, and hypercoagulability cites three factors that predispose to the formation of venous thrombosis. The pneumoperitoneum created during laparoscopic surgery results in an intraabdominal pressure that exceeds the pressure of venous blood return from the legs. This may alter venous hemodynamics enough to result in venous stasis in the legs, thus increasing the risk of thrombus formation. Duplex ultrasound was used to measure the diameter and venous flow volume of the common femoral vein during laparoscopic cholecystectomy. Measurements were obtained at three different times: after induction of anesthesia but prior to creation of pneumoperitoneum, during pneumoperitoneum, and after abdominal deflation but prior to reversal of anesthesia. After insufflation of the abdomen, the mean cross-sectional area of the common femoral vein increased (0.83 to 1.15 cm2; p = 0.0024) and the venous flow decreased (11.00 to 6.06 cm3/sec; p = 0.0008). After deflation of the abdomen, there was no significant change in cross-sectional area of the common femoral vein, but there was an increase in venous flow (6.06 to 9.94 cm3/sec; p = 0.0005). Abdominal insufflation during laparoscopic cholecystectomy results in dilation of and decreased flow in the common femoral vein. After deflation of the abdomen, flow in the vein returns to baseline levels.

Adult↗

PubMed1994

Does the asymptomatic limb harbor deep venous thrombosis?

Deep venous thrombosis (DVT) is a great masquerader that cannot be reliably predicted by a patient's symptoms, history, or risk factors. Bilateral lower extremity duplex ultrasonography scans were made of 2,511 patients and analyzed to identify, if possible, a population in which a unilateral study would be appropriate. A total of 1,086 (43%) patients were found to have deep venous thrombosis--742 (30%) unilateral and 344 (14%) bilateral. Of the patients with DVT for whom side-of-symptom information was recorded, 64% had symptoms referable to the involved extremity and 36% had symptoms referable to the contralateral extremity. Of the 362 patients who had asymptomatic lower extremities, 128 (35%) had DVT. Moreover, clots were found in asymptomatic limbs in an additional 263 patients whose contralateral limb was symptomatic. Logistic regression analysis did not reveal combinations of symptoms and risk factors that could predict DVT. If DVT is suspected, the patient should undergo bilateral lower extremity duplex scanning.

Acute Disease↗