PubMed Health⌕ Search

Biomedical subjects

M M Levy

Publications and source records attributed to M M Levy.

34 records · Page 2Linked to original sources
PubMed1995

Frequency of mortality and myocardial infarction during maximizing oxygen delivery: a prospective, randomized trial.

OBJECTIVES: To determine the frequency of myocardial infarction and mortality during treatment that increased oxygen delivery (DO2) to > or = 600 mL/min/m2. To define the characteristics of patients achieving a high DO2 without inotropes in order to guide future studies. DESIGN: A prospective, randomized, controlled trial. SETTING: Two surgical intensive care units at The Queen's Medical Center in the University of Hawaii Surgical Residency Program. PATIENTS: Eighty-nine surgical patients (> or = 18 yrs of age), who were admitted to a surgical intensive care unit and who required pulmonary artery catheter monitoring, were selected for the study. Diagnoses included sepsis, septic shock, adult respiratory distress syndrome, or hypovolemic shock. Patients facing imminent death were excluded from the study. INTERVENTIONS: The treatment group received fluid boluses, blood products, and inotropes, as needed, to achieve a DO2 of > or = 600 mL/min/m2 in the first 24 hrs. Using the same interventions, we treated the control group to reach a DO2 of 450 to 550 mL/min/m2. MEASUREMENTS AND MAIN RESULTS: Hemodynamic measurements were obtained every 4 hrs until the pulmonary artery catheter was removed. DO2 and oxygen consumption were calculated by standard formulas. Serial creatine kinase myocardial fraction and electrocardiograms were documented for the first 48 hrs after study entry and for any new onset of arrhythmia or increasing hemodynamic instability. The patients who generated a high DO2 (> or = 600 mL/min/m2) with only preload treatment were reflective of patients with better cardiac reserve and low mortality rates. These patients, from both treatment and control groups, were excluded in the final analysis. The treatment group who received inotropes to achieve the high DO2 had a 14% mortality rate. Those patients who failed to achieve the high DO2 had a 67% mortality rate, and the control group who achieved a normal DO2 had a 62% mortality rate (p = .005). The frequency of myocardial infarction after study entry was 5.6% (five of 89 patients). This rate was not higher among the groups who received inotropes. Logistic regression analysis showed that age of > or = 50 yrs could be used to classify patients as not self-generating, with an 83% chance of being correct. CONCLUSIONS: The group that required catecholamines to achieve a DO2 of > or = 600 mL/min/m2 had a lower mortality rate, with no increase in the frequency of myocardial infarction. Future prospective, controlled trials examining select groups of patients (age > or = 50 yrs) may demonstrate a difference between control and treatment groups by eliminating the majority of patients who generate the high DO2 with only preload augmentation.

Aged↗
PubMed1995

Work of breathing as a weaning parameter in mechanically ventilated patients.

STUDY OBJECTIVE: Predicting patient responses to changes in ventilatory support or weaning is primarily based on bedside measure of respiratory mechanics and clinical judgement. Work of breathing (WOB) has been considered to be the best predictive factor in weaning. This study evaluated patient WOB as a predictive measure of weaning and extubation. DESIGN: Blinded, descriptive evaluation of the accuracy of preextubation values of patient WOB in predicting successful extubation. SETTING: Critical care units of 500-bed major teaching hospital of the University of Hawaii. PATIENTS: Twenty-four patients from the medical and surgical ICU were enrolled in the study. Patient diagnoses included COPD, ARDS, pneumonia, and renal failure. MEASUREMENTS AND MAIN RESULTS: In all patients, weaning from mechanical ventilation was accomplished by the clinical ICU teams who were blinded to the patient WOB. After extubation, patient WOB was compared with extubation attempts. In 14 patients, WOB was elevated above normal levels prior to successful extubation, while only 1 patient whose WOB was abnormal prior to extubation required reintubation within 24 h. WOB and clinical parameters were normal in 10 successfully extubated patients. CONCLUSIONS: In this group of mechanically ventilated patients, measurement of patient WOB was less accurate than conventional weaning parameters and clinical judgement for predicting successful extubation. This clinical evaluation study suggests that WOB alone is inadequate as a weaning parameter.

APACHE↗
PubMed1993

Effect of maximizing oxygen delivery on morbidity and mortality rates in critically ill patients: a prospective, randomized, controlled study.

OBJECTIVE: To determine the effects of optimizing oxygen delivery (DO2) to "supranormal" levels on morbidity and mortality in patients with sepsis, septic shock, and adult respiratory distress syndrome. DESIGN: A prospective, randomized, controlled trial. SETTING: A 16-bed surgical intensive care unit (ICU) and 14-bed mixed medical/surgical ICU in two separate hospitals in the University of Hawaii Surgical and Internal Medicine Residency programs. PATIENTS: During a 1-yr period, 67 patients who had pulmonary artery catheters and who met the criteria for sepsis or septic shock, adult respiratory distress syndrome, or hypovolemic shock were enrolled in the study. Patients admitted to the ICU who were < 18 yrs old, or with a do-not-resuscitate order, or those patients who faced imminent death (< 24 hrs), such as those patients with uncontrollable hemorrhage or brain death, were excluded from the study. INTERVENTIONS: Patients were randomized into treatment and control groups. The treatment group was assigned a therapeutic DO2 indexed (DO2I) goal of > 600 mL/min/m2. Interventions to attain this goal included fluid boluses, administration of blood products, and the use of inotropes. The control group was not assigned to a specific therapeutic goal other than "normal" values of DO2I of 450 to 550 mL/min/m2. Every attempt was made to reach the therapeutic goals within the first 24 hrs after entry into the study. Hemodynamic measurements were obtained on study patients every 4 hrs until the end of the study. The severity of illness was evaluated using the Therapeutic Intervention Scoring System, and the Acute Physiology and Chronic Health Evaluation II scoring system. MEASUREMENTS AND MAIN RESULTS: There were 32 patients in the control group and 35 patients in the treatment group. The groups were similar in age, sex, number of organ dysfunctions, Acute Physiology and Chronic Health Evaluation II and Therapeutic Intervention scores. There were no statistical differences between the two groups in mortality, development of organ failure, ICU days, and hospital days. Upon analysis, it became apparent that the patients comprised clinically distinct subgroups, including: a) a treatment group who achieved supranormal DO2I; b) a control group with normal DO2I; c) a treatment group who failed to reach target DO2I; d) a control group who self-generated to high DO2I values; and e) a small number of patients who could not even reach a normal DO2I of 450 mL/min/m2. These subgroups were found to be similar and matched. The mortality rate was significantly lower for patients in groups who reached supranormal values of DO2I whether treated or self-generated as compared with patients who reached normal DO2I values (14% vs. 56%, p = .01). CONCLUSIONS: Although there was no statistically significant difference in the control vs. treatment groups, subgroup analysis demonstrated a strong, significant difference between patients with supranormal values of oxygen transport vs. patients with normal levels of DO2. Supranormal values of DO2I, whether self-generated or as a result of treatment, resulted in a statistically significant decrease in mortality rate. This study adds to the weight of evidence that current standard of care of treating critically ill patients to normal DO2I should be reconsidered, and that maximizing to high DO2I might be a more appropriate therapeutic end-point.

Adult↗
PubMed1990

The effect of islet cell culture in vitro at 24 degrees C on graft survival and MHC antigen expression.

A period of in vitro culture prior to transplantation has been shown to prolong the survival of many types of MHC-incompatible endocrine grafts. The effectiveness of this strategy has been attributed to a selective depletion of intragraft antigen-presenting cells. We report that in vitro culture at 24 degrees C results in a significantly better survival of rat isolated islet allografts than does culture at 37 degrees C. Using in vitro assays of APC activity, we were unable to detect differences in the quantity of residual intraislet APCs between 24 degrees C and 37 degrees C culture preparations. In contrast, islet endocrine cells cultured at 24 degrees C evidenced a reduced level of cell surface class I MHC antigen expression and were significantly less vulnerable to lysis in vitro by CTL. These findings suggest that culture at 24 degrees C produces islet alterations other than APC depletion, and that its beneficial effect on graft survival correlates with a reduction in endocrine cell class I MHC antigen expression.

Animals↗
PubMed1984

The 2-deoxyglucose test as a supplement to fasting for detection of childhood hypoglycemia.

The acute response to simulated hypoglycemia induced by 2-deoxyglucose (2DG) was compared with the prolonged fasting test as a possible screening test for detection of childhood hypoglycemia. Ten children, ages 2-9 yr, without a documented history of hypoglycemia were classified retrospectively as reference subjects. While fasting, their plasma glucose decreased to an average of 50 mg/dl (range, 30-74) between 28-36 h. After infusion of 2DG, 50 mg/kg IV over 30 min, their plasma glucose increased by an average of 35 mg/dl (range, 19-56) between 60-120 min. The half-life of plasma 2DG was 48 min. Twenty-three other children in the same age range had an abnormal response to one or both of these tests. Thirteen of these children became definitely hypoglycemic while fasting (glucose less than 30 mg/dl) and also failed to increase their plasma glucose by more than 10 mg/dl after 2DG. Five children had plasma glucose values between 30-40 mg/dl during the first 24 h of fasting that were associated with a change in mental status but responded to 2DG with an increase in plasma glucose. The remaining five subjects had an apparently normal response to fasting but did not respond to 2DG; two of these had documented spontaneous hypoglycemia. No cases of documented hypoglycemia were undetected by either test. It is concluded that the 2DG test is a short safe supplement to fasting which is equally effective as the prolonged fasting test in detecting hypoglycemia. Neither test alone is completely reliable, but the combination is complementary.

Blood Glucose↗
PubMed1984

The 2-deoxyglucose test as a supplement to fasting for detection of childhood hypoglycemia.

The acute response to simulated hypoglycemia induced by 2-deoxyglucose (2DG) was compared with the prolonged fasting test as a possible screening test for detection of childhood hypoglycemia. Ten children, ages 2-9 yr, without a documented history of hypoglycemia were classified retrospectively as reference subjects. While fasting, their plasma glucose decreased to an average of 50 mg/dl (range, 30-74) between 28-36 h. After infusion of 2DG, 50 mg/kg IV over 30 min, their plasma glucose increased by an average of 35 mg/dl (range, 19-56) between 60-120 min. The half-life of plasma 2DG was 48 min. Twenty-three other children in the same age range had an abnormal response to one or both of these tests. Thirteen of these children became definitely hypoglycemic while fasting (glucose less than 30 mg/dl) and also failed to increase their plasma glucose by more than 10 mg/dl after 2DG. Five children had plasma glucose values between 30-40 mg/dl during the first 24 h of fasting that were associated with a change in mental status but responded to 2DG with an increase in plasma glucose. The remaining five subjects had an apparently normal response to fasting but did not respond to 2DG; two of these had documented spontaneous hypoglycemia. No cases of documented hypoglycemia were undetected by either test. It is concluded that the 2DG test is a short safe supplement to fasting which is equally effective as the prolonged fasting test in detecting hypoglycemia. Neither test alone is completely reliable, but the combination is complementary.

Adolescent↗
PubMedDate not supplied

Clinical and financial outcomes of lateral rotation low air-loss therapy in patients in the intensive care unit.

OBJECTIVE: To determine the clinical impact and cost-effectiveness of two lateral rotation low air-loss therapy beds and their supporting protocols in the treatment of critically ill patients. DESIGN: Retrospective-cohort (2:1 design) study consisting of chart reviews of patients on two types of lateral rotation low air-loss therapy and their protocols from January 1992 through July 1993. SETTING: Three intensive care units (ICUs) (30 medical and surgical beds) in a 506-bed community hospital. PATIENTS: Fifty-six critically ill patients admitted to the ICU and prescribed lateral rotation therapy. Patients treated on both beds were excluded from the study. MEASUREMENTS: Data were collected on age, sex, Acute Physiology and Chronic Health Evaluation II score, Therapeutic Intervention Scoring System on admission to the ICU, and the time interval (number of days) from ICU admission until placement on a specialty bed (Lag Time). Outcome measurements included presence of pneumonia, adult respiratory distress syndrome, and multiorgan system dysfunction during the ICU stay, and the number of intubation days, ICU hours, hospital length of stay, and mortality during hospitalization. RESULTS: Statistically significant differences in group outcomes were found as follows: (1) pneumonia (p = 0.001), (2) adult respiratory distress syndrome (p = 0.002), (3) hospital length of stay (p = 0.04), and (4) hospital costs (p = 0.0001). CONCLUSIONS: In this study, patients treated by a prevention protocol with the Restcue beds (Support Systems International, Inc., Charleston, S.C.) had better clinical and financial outcomes than patients treated on Biodyne beds (Kinetic Concepts, Inc., San Antonio, Texas) with a more restricted, cost-conscious protocol aimed primarily at patients who have or who are at a higher risk for severe pneumonia, presence of septic shock, or adult respiratory distress syndrome.

Adult↗