Search PubMed⌕ Search

Biomedical subjects

L Samuels

Publications and source records attributed to L Samuels.

14 recordsLinked to original sources
PubMed1998

Heart transplantation in patients with heparin-induced thrombocytopenia on the Novacor left ventricular assist system.

We report on two patients with development of heparin-induced thrombocytopenia with thrombosis while on the Novacor left ventricular assist system. Heart transplantation was successfully performed in both patients with heparin used for cardiopulmonary bypass after careful monitoring of heparin-associated antibodies. The approach to the patients' management and potential alternatives for anticoagulation are discussed.

Anticoagulants↗
PubMed1997

Utility of a software assistant in critical care case review.

A computer program (the Audit Assistant) was developed to help physicians review the care of critically ill emergency department (ED) patients. The program is an example of a new class of decision aids that serves to remind physicians to consider possibilities, not an artificial intelligence program that actually attempts to simulate clinical reasoning. The goal of such programs is to enable physicians to reduce errors--in this case to enable reviewers to notice more of the errors in care in the cases they are reviewing. The objective of this study was to demonstrate on a small set of complex cases that the tested computer program enables the physician to perform a better quality review. The issue of what constitutes improved case review is addressed. In the first part of the study, reviewers reviewed two mock charts without using the Audit Assistant and then immediately reviewed the charts again with the assistance of the program. The reviews were compared. In the second part of the study, a second reviewer also compared the utility of the review of the first reviewer alone and the Audit Assistant output as an aid to review, using an additional mock chart. Six emergency physicians participated; each was a quality assurance director for the ED of one Cleveland area hospital. For the physicians reviewing without the Audit Assistant, 41% of critical actions were listed by three or four reviewers. For those using the Audit Assistant, 83% of critical actions were listed by three or four reviewers. All reviewers preferred the Audit Assistant-suggested list to the critical action list generated by a previous reviewer not using the Audit Assistant (P < .02). Use of the Audit Assistant improved the completeness and the consistency of physician review of mock charts of critically ill ED patients in a small series of cases. The critical actions added for review were important, as demonstrated by the preferential addition of critical actions chosen by other reviewers who were not using the computer program.

Critical Care↗
PubMed1993

Reconstruction of radiation-induced chest wall lesions.

Radiation-related ulcers of the chest wall provide a great challenge to reconstructive surgeons because of the necessity of protecting the underlying vital structures and the difficulty in repairing irradiated tissues. To evaluate the efficacy of treatment, 24 patients who underwent reconstruction of radiation related ulcers of the chest wall were retrospectively reviewed. A variety of muscle and musculocutaneous flaps as well as omentum and microvascular tissue transfers were used to reconstruct these defects. The defects in the chest wall arose from spontaneous breakdown of irradiated tissue, tumor recurrence, or nonhealing after surgical procedures performed in the irradiated field. Our treatment protocol consisted of aggressive debridement of all affected tissues including skeletal tissues when necessary. The application of a tension free closure using a flap was then performed. Skeletal support was provided in three reconstructions. There were no mortalities, the morbidity rate was 29% (six minor, one major complication), and the mean hospital stay was 10.9 days. None of the patients required prolonged ventilator support. In all but 2 patients, who were left with small chronic granulating nonhealing wounds, complete wound healing was achieved. We conclude that chest wall reconstruction of radiation-related ulcers can be achieved with minimal morbidity in an acceptable period of inpatient hospital care using a variety of vascularized tissue transfers.

Aged↗
PubMed1993

Revascularized diabetic limbs: positional changes in regional perfusion index.

We measured pre- and postoperative ankle:brachial index (ABI), regional perfusion index (RPI = foot/chest transcutaneous oxygen tension [TcpO2]), and variation in RPI with limb elevation in 22 ischemic lower extremities of 20 patients to compare ABI and RPI measurements for quantifying limb perfusion and analyze perioperative positional changes in RPI. Measurements were compared, using t tests, with all limbs grouped according to severity of clinical ischemia and, again, according to presence or absence of diabetes. Preoperative mean and mean post-revascularization increases in ABI values ranged from 0.27 to 0.48 and 0.40 to 0.54, respectively; corresponding RPI values ranged from 0.18 to 0.45 and 0.48 to 0.60, respectively. Pre- and postoperative decreases in RPI with elevation ranged from 0.07 to 0.11 and 0.11 to 0.23, respectively. ABI and RPI values were equally effective in assessing clinical ischemia preoperatively and increased perfusion postoperatively, regardless of degree of ischemia or diabetes. Upon elevation, all limbs exhibited larger decrements in blood flow to the skin postoperatively compared to preoperatively, as estimated by RPI. However, postoperative positional decrease in RPI was greater in diabetics compared with nondiabetics (0.23 +/- 0.12 vs 0.12 +/- 0.06; P < 0.05), suggesting postoperative elevation of diabetic limbs with ischemic skin lesions may be unadvisable.

Adult↗
PubMed1988

Safety and diagnostic accuracy of dipyridamole-thallium imaging in the elderly.

The noninvasive diagnosis of coronary artery disease in the elderly can occasionally be difficult. Intravenous dipyridamole-thallium imaging is a potentially useful diagnostic test to determine presence and severity of coronary disease; however, the safety of the procedure has not been determined in an older population. The side effect profile and frequency of severe ischemic responses after 0.56 mg/kg of intravenous dipyridamole were compared in 101 patients greater than or equal to 70 years old and 236 patients less than 70 years old. There were no side effects in 64% and 62% of patients greater than or equal to 70 and less than 70 years old, respectively (p = NS). Among the 337 patients tested, there were no complications of myocardial infarction or death. The most common cardiac side effect was chest pain, which occurred in 21 (21%) of the 101 patients aged greater than or equal to 70 years and in 64 (27%) of the 236 patients less than 70 years (p = NS). Aminophylline was required to reverse cardiac or noncardiac side effects in 15 (15%) and 36 (15%) of the patients greater than or equal to 70 and less than 70 years old, respectively (p = NS). A severe ischemic response occurred in 2% and 2.5% of patients greater than or equal to 70 and less than 70 years old, respectively (p = NS). The sensitivity of intravenous dipyridamole-thallium imaging for obstructive coronary artery disease was 86% (25 of 29) and 83% (68 of 82) in older and younger patients, respectively (p = NS); the specificity was 75% (6 of 8) and 70% (16 of 23), respectively (p = NS). Thus, intravenous dipyridamole-thallium imaging is a safe noninvasive method for assessment of older patients with obstructive coronary disease; its side effect profile and diagnostic accuracy are similar to those seen in younger patients. The technique is associated with severe ischemic responses in only a small minority of patients.

Adult↗
PubMed1979

Sex differences in concordance rates for schizophrenia in twins.

In response to my discussion of sex differences in concordance rates for schizophrenia in twins, Lewine (1979) noted that male schizophrenics are hospitalized earlier than females. He questioned whether females had been followed through the risk period. To clarify, I calculated the age at followup of discordant twins in three studies. In Gottesman and Shields' (1972) study, the majority of both male and female co-twins were still under the age of 45. In contrast, all but a few of Kringlen's (1967a, 1967b, 1968) and Fischer's (1973) co-twins were 45 or over. Their findings support the conclusion that recent twin studies show no significant sex differences in concordance.

Diseases in Twins↗
PubMed1978

Sex differences in concordance rates for schizophrenia: finding or artifact?

The literature on schizophrenia has reported a trend toward higher concordance rates for females in both monozygotic and dizygotic same-sexed twins. The validity of this finding is open to question. Rosenthal (1961 and 1962) pointed out that females are more likely than males to become inhabitants of chronic wards. Most of the studies reporting a sex difference used resident hospital populations. Gottesman and Shields (1972) noted that the sex difference disappeared when samples were based upon consecutive admissions. Sex differences have vanished in recent studies both as a result of changing research methods and the changing role of women in society.

Diseases in Twins↗
PubMedDate not supplied

Cardiac ventricular support. Considerations for psychiatry.

Cardiac ventricular support is fostering additional roles for psychiatric consultation with this vulnerable end-of-life cardiac group. Incidence of premorbid and postsurgical psychiatric disorders (Axis I), psychotropic use, neurologic events, and mortality was obtained for 21 Novacor left-ventricular assist system patients prospectively and 13 Abiomed left/right ventricular-assist device patients retrospectively. This fragile patient population and their families warrant involvement for psychiatry because of the extreme conditions and consequences associated with mechanical cardiac assistance. The authors address psychiatric morbidity and neurobehavioral modifications associated with ventricular support.

Adaptation, Psychological↗