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M J Breslow

Publications and source records attributed to M J Breslow.

At least 19 recordsLinked to original sources
PubMed2001

Nicardipine versus nitroprusside for breakthrough hypertension following carotid endarterectomy.

STUDY OBJECTIVE: To evaluate the effectiveness of nicardipine and nitroprusside for breakthrough hypertension following carotid endarterectomy. DESIGN: Prospective, randomized, double-blind, controlled effectiveness trial. SETTING: University-based surgical intensive care unit. PATIENTS: 60 ASA physical status I, II, III, and IV patients experiencing breakthrough hypertension at the time of admission to the intensive care unit (ICU). INTERVENTIONS: Patients received either nicardipine (n = 29) and placebo or nitroprusside (n = 31) and placebo for up to 6 hours postoperatively. Loading doses of nicardipine were provided, but placebo was used as a load for patients randomized to nitroprusside. MEASUREMENTS AND MAIN RESULTS: Rapidity and variability of blood pressure (BP) control were assessed. During the first 10 minutes, 83% of nicardipine patients compared to 23% of nitroprusside-treated patients, achieved BP control (p < 0.01). Following initial control, 12 nicardipine- and 24 nitroprusside-treated patients required additional titration of their infusions to maintain blood pressure within the targeted range (p < 0.05). No patient suffered a stroke, myocardial infarction, or was returned to the operating room (OR) for bleeding. CONCLUSIONS: Nicardipine administration produced more rapid BP control, most likely related to the administration of a loading dose. In addition to more rapid control, nicardipine-treated patients had less variability in BP and required significantly fewer additional interventions. Although no patient suffered a major event during this study, this study was not powered sufficiently to assess safety.

Aged↗
PubMed2001

Weight loss is not associated with hyperleptinemia in humans with pancreatic cancer.

Pathological weight loss is a feature of many diseases and contributes to mortality and morbidity. Although cytokines have been implicated in some models of pathological weight loss, little is known about cellular mechanisms responsible for cachexia in patients with cancer. Leptin is a fat cell product that acts centrally to reduce appetite and decrease metabolism. Leptin synthesis is stimulated by cytokines, and circulating levels of cytokines are elevated in some cancer patients. We hypothesized that cytokine-induced hyperleptinemia contributes to pathological weight loss in patients with pancreatic cancer. To evaluate this hypothesis, fasting serum leptin concentrations were measured in 64 patients undergoing surgery for pancreatic cancer. Preoperative interviews were used to assess body weight and appetite history. Thirty of 64 pancreatic cancer patients had cachexia (weight loss of >10% over the 6 months before surgery). Self-reported loss of appetite was associated with the presence of cachexia. Leptin concentrations, when corrected for body mass index, were lower than levels reported in healthy humans. Six patients had leptin levels more than 2 times those predicted by body mass index. There was no association between patients with increased leptin concentration and weight loss or anorexia. We conclude that a reduced appetite contributes to weight loss in patients with pancreatic cancer. High plasma leptin levels, however, do not appear to contribute to cachexia in these patients.

Aged↗
PubMed2001

Distal biceps tendon ruptures: a historical perspective and current concepts.

Distal biceps tendon rupture is a relatively rare injury most commonly seen in the dominant extremity of men between 40 and 60 years of age. It occurs when an eccentric extension force is applied to a contracting biceps muscle. The hallmark finding is a palpable defect in the distal biceps, which is accentuated by elbow flexion. Radiographic evaluation is usually not necessary. Acute surgical repair is advocated for optimal return of function by either a one-incision or a modified two-incision muscle-splitting technique. The arm is protected for 6 to 8 eight weeks after surgery. Unrestricted range of motion and gentle strengthening may begin after the 6 - 8 week protection period. Return to unrestricted activity is usually allowed by 5 months after surgery.

Arm Injuries↗
PubMed2000

Bundle-branch block as a risk factor in noncardiac surgery.

BACKGROUND: Despite extensive data examining perioperative risk in patients with coronary artery disease, little attention has been devoted to the implications of conduction system abnormalities. OBJECTIVE: To define the clinical significance of bundle-branch block (BBB) as a perioperative risk factor. METHODS: Retrospective, cohort-controlled study of all noncardiac, nonophthalmologic, adult patients with BBB seen in our preoperative evaluation center. Medical charts were reviewed for data regarding cardiovascular disease, surgical procedure, type of anesthesia, intravascular monitoring, and perioperative complications. RESULTS: Bundle-branch block was present in 455 patients. Right BBB (RBBB) was more common than left BBB (LBBB) (73.8% vs 26.2%). Three patients with LBBB and 1 patient with RBBB died; 1 patient had a supraventricular tachyarrhythmia. Three of the 4 deaths were sepsis related. There were 2 (0.4%) deaths in the control group. There was no difference in mortality between BBB and control groups (P = .32). Subgroup analysis suggested an increased risk for death in patients with LBBB vs controls (P = .06; odds ratio, 6.0; 95% confidence interval, 1.2-100.0) and vs RBBB (P = .06; odds ratio, 8.7; 95% confidence interval, 1.2-100.0). CONCLUSIONS: The presence of BBB is not associated with a high incidence of postoperative cardiac complications. Perioperative mortality is not increased in patients with RBBB and not directly attributable to cardiac complications in patients with LBBB. These data suggest that the presence of BBB does not significantly increase the likelihood of cardiac complications following surgery, but that patients with LBBB may not tolerate the stress of perioperative noncardiac complications.

Adult↗
PubMed2000

ICU telemedicine. Organization and communication.

Telemedicine offers off-site physicians the ability to care for patients by providing them with audio-video links and access to relevant clinical data. Traditionally, this care modality has been used to overcome geographic barriers by bringing needed expertise to patients in remote locations. The same technology can be used to bring intensivist expertise to ICU patients. A recent clinical trial has confirmed the efficacy of remote ICU care, with decreases in mortality, complications, and costs that are analogous to those observed with on-site intensivists. If a single, intensivist-led care team can provide round-the-clock, proactive care to patients in multiple ICUs simultaneously, this care modality can be used to overcome current deficiencies in ICU care related to inadequate intensivist availability.

Forecasting↗
PubMed2000

Intensive care unit telemedicine: alternate paradigm for providing continuous intensivist care.

OBJECTIVE: Intensive care units (ICUs) account for an increasing percentage of hospital admissions and resource consumption. Adverse events are common in ICU patients and contribute to high mortality rates and costs. Although evidence demonstrates reduced complications and mortality when intensivists manage ICU patients, a dramatic national shortage of these specialists precludes most hospitals from implementing an around-the-clock, on-site intensivist care model. Alternate strategies are needed to bring expertise and proactive, continuous care to the critically ill. We evaluated the feasibility of using telemedicine as a means of achieving 24-hr intensivist oversight and improved clinical outcomes. DESIGN: Observational time series triple cohort study. SETTING: A ten-bed surgical ICU in an academic-affiliated community hospital. PATIENTS: All patients whose entire ICU stay occurred within the study periods. INTERVENTIONS: A 16-wk program of continuous intensivist oversight was instituted in a surgical ICU, where before the intervention, intensivist consultation was available but there were no on-site intensivists. Intensivists provided management during the intervention using remote monitoring methodologies (video conferencing and computer-based data transmission) to obtain clinical information and to communicate with on-site personnel. To assess the benefit of the remote management program, clinical and economic performance during the intervention were compared with two 16-wk periods within the year before the intervention. MEASUREMENTS AND MAIN RESULTS: ICU and hospital mortality (observed and Acute Physiology and Chronic Health Evaluation III, severity-adjusted), ICU complications, ICU and hospital length-of-stay, and ICU and hospital costs were measured during the 3 study periods. Severity-adjusted ICU mortality decreased during the intervention period by 68% and 46%, compared with baseline periods one and two, respectively. Severity-adjusted hospital mortality decreased by 33% and 30%, and the incidence of ICU complications was decreased by 44% and 50%. ICU length of stay decreased by 34% and 30%, and ICU costs decreased by 33% and 36%, respectively. The cost savings were associated with a lower incidence of complications. CONCLUSIONS: Technology-enabled remote care can be used to provide continuous ICU patient management and to achieve improved clinical and economic outcomes. This intervention's success suggests that remote care programs may provide a means of improving quality of care and reducing costs when on-site intensivist coverage is not available.

APACHE↗
PubMed2000

Cervical spine injuries in football.

The game of football, as it is played today, poses serious risk of injury for players of all ages. Injury may occur to any structure of the spinal column, including its bony, ligamentous and soft tissue components. The majority of cervical spine injuries occurring in football are self limited, and a full recovery can be expected. While these injuries are relatively uncommon, cervical spine injuries represent a significant proportion of athletic injuries that can produce permanent disability. The low incidence of cervical spine injuries has lead to a lack of emergency management experience of on-site medical staff. This paper will review the numerous injuries sustained by the cervical spine in football players and provide insights into prevention and guidelines for return to play.

Adult↗
PubMed1999

Organizational characteristics of intensive care units related to outcomes of abdominal aortic surgery.

CONTEXT: Morbidity and mortality rates in intensive care units (ICUs) vary widely among institutions, but whether ICU structure and care processes affect these outcomes is unknown. OBJECTIVE: To determine whether organizational characteristics of ICUs are related to clinical and economic outcomes for abdominal aortic surgery patients who typically receive care in an ICU. DESIGN: Observational study, with patient data collected retrospectively and ICU data collected prospectively. SETTING: All Maryland hospitals that performed abdominal aortic surgery from 1994 to 1996. PATIENTS AND PARTICIPANTS: We analyzed hospital discharge data for patients in non-federal acute care hospitals in Maryland who had a principal procedure code for abdominal aortic surgery from January 1994 through December 1996 (n = 2987). We obtained information about ICU organizational characteristics by surveying ICU medical directors at the 46 Maryland hospitals that performed abdominal aortic surgery. Thirty-nine (85%) of the ICU directors completed this survey. MAIN OUTCOME MEASURES: In-hospital mortality and hospital and ICU length of stay. RESULTS: For patients undergoing abdominal aortic surgery, in-hospital mortality varied among hospitals from 0% to 66%. In multivariate analysis adjusted for patient demographics, comorbid disease, severity of illness, hospital and surgeon volume, and hospital characteristics, not having daily rounds by an ICU physician was associated with a 3-fold increase in in-hospital mortality (odds ratio [OR], 3.0; 95% confidence interval [CI], 1.9-4.9). Furthermore, not having daily rounds by an ICU physician was associated with an increased risk of cardiac arrest (OR, 2.9; 95% CI, 1.2-7.0), acute renal failure (OR, 2.2; 95% CI, 1.3-3.9), septicemia (OR, 1.8; 95% CI, 1.2-2.6), platelet transfusion (OR, 6.4; 95% CI, 3.2-12.4), and reintubation (OR, 2.0; 95% CI, 1.0-4.1). Not having daily rounds by an ICU physician, having an ICU nurse-patient ratio of less than 1:2, not having monthly review of morbidity and mortality, and extubating patients in the operating room were associated with increased resource use. CONCLUSIONS: Organizational characteristics of ICUs are related to differences among hospitals in outcomes of abdominal aortic surgery. Clinicians and hospital leaders should consider the potential impact of ICU organizational characteristics on outcomes of patients having high-risk operations.

Aged↗
PubMed1999

The stress response of critical illness.

The integrated stress response to tissue trauma is crucial for the maintenance of homeostasis. An exaggerated or prolonged response may be detrimental in compromised patients. Knowledge of the involved afferent pathways will suggest therapeutic interventions that may modulate the intensity of the stress response. Described are these concepts as they relate to perioperative medicine.

Afferent Pathways↗
PubMed1999

Effect of leptin deficiency on metabolic rate in ob/ob mice.

Reduced metabolic rate may contribute to weight gain in leptin-deficient (ob/ob) mice; however, available studies have been criticized for referencing O2 consumption (VO2) to estimated rather than true lean body mass. To evaluate whether leptin deficiency reduces energy expenditure, four separate experiments were performed: 1) NMR spectroscopy was used to measure fat and nonfat mass, permitting VO2 to be referenced to true nonfat mass; 2) dietary manipulation was used in an attempt to eliminate differences in body weight and composition between ob/ob and C57BL/6J mice; 3) short-term effects of exogenous leptin (0.3 mg. kg-1. day-1) on VO2 were examined; and 4) body weight and composition were compared in leptin-repleted and pair-fed ob/ob animals. ob/ob animals had greater mass, less lean body mass, and a 10% higher metabolic rate when VO2 was referenced to lean mass. Dietary manipulation achieved identical body weight in ob/ob and C57BL/6J animals; however, despite weight gain in C57BL/6J animals, percent fat mass remained higher in ob/ob animals (55 vs. 30%). Exogenous leptin increased VO2 in ob/ob but not control animals. Weight loss in leptin-repleted ob/ob mice was greater than in pair-fed animals (45 vs. 17%). We conclude, on the basis of the observed increase in VO2 and accelerated weight loss seen with leptin repletion, that leptin deficiency causes a reduction in metabolic rate in ob/ob mice. In contrast, these physiological studies suggest that comparison of VO2 in obese and lean animals does not produce useful information on the contribution of leptin to metabolism.

Animals↗
PubMed1998

Beta-adrenergic blockade accelerates conversion of postoperative supraventricular tachyarrhythmias.

BACKGROUND: Postoperative supraventricular tachyarrhythmia is a common complication of surgery. Because chemical cardioversion is often ineffective, ventricular rate control remains a principal goal of therapy. The authors hypothesized that patients with supraventricular tachyarrhythmia after major noncardiac surgery who receive intravenous beta-adrenergic blockade for ventricular rate control would experience conversion to sinus rhythm at a rate that differs from those receiving intravenous calcium channel blockade. METHODS: The rate of conversion to sinus rhythm at 2 and 12 h after treatment was examined in 64 cases of postoperative supraventricular tachyarrhythmia. After adenosine administration, patients who remained in supraventricular tachyarrhythmia were prospectively randomized to receive either intravenous diltiazem or intravenous esmolol for ventricular rate control (unblinded). Loading and infusion rates were adjusted to achieve equivalent degrees of ventricular rate control. RESULTS: Patients were similar with regard to age and Apache III score. Most patients in both groups had atrial fibrillation (esmolol, 79%; diltiazem, 81%), and none experienced stable conversion with adenosine. Patients randomized to receive esmolol experienced a 59% rate of conversion to sinus rhythm within 2 h of treatment, compared with only 33% for patients randomized to receive diltiazem (intention to treat, P = 0.049; odds ratio, 2.9; 95% confidence interval, 1.046 to 7.8). After 12 h of therapy, the number of patients converting to sinus rhythm increased in both groups (esmolol, 85%; diltiazem, 62%), and the rates of conversion no longer differed significantly. Ventricular rates when supraventricular tachyarrhythmia began and after 2 and 12 h of rate control therapy were similar in the two treatment groups. The in-hospital mortality rate and length of stay in the intensive care unit were not significantly influenced by treatment group. CONCLUSIONS: Among adenosine-resistant patients in the intensive care unit with atrial fibrillation after noncardiac surgery, intravenous esmolol produced a more rapid (2-h) conversion to sinus rhythm than did intravenous diltiazem.

Adrenergic beta-Antagonists↗
PubMed1998

"Renal dose" dopamine in surgical patients: dogma or science?

OBJECTIVE: "Renal dose" dopamine is widely used in the perioperative period to provide renal protection. A comprehensive review of the literature was performed to determine whether dopamine does in fact confer protection on the kidneys of surgical patients. SUMMARY BACKGROUND DATA: Studies in healthy animals and human volunteers reveal that dopamine causes diuresis and natriuresis, as well as some degree of renal vasodilatation. RESULTS: Studies of the perioperative use of dopamine fail to demonstrate any benefit of dopamine in preventing renal failure. Studies in congestive heart failure, critical illness, and sepsis also fail to show any benefit of dopamine other than diuresis. Further, dopamine administration is not completely without risk, because of dopamine's catecholamine and neuroendocrine functions. CONCLUSIONS: Routine use of prophylactic "renal dose" dopamine in surgical patients is not recommended.

Animals↗
PubMed1998

Radial artery pressure monitoring underestimates central arterial pressure during vasopressor therapy in critically ill surgical patients.

OBJECTIVES: Radial artery pressure is known to differ from central arterial pressure in normal patients (distal pulse amplification) and in the early postcardiopulmonary bypass period. The adequacy of the radial artery as a site for blood pressure monitoring in critically ill patients receiving high-dose vasopressors has not been carefully examined. DESIGN: Prospective observational study comparing simultaneous intra-arterial measurements of radial (peripheral) and femoral artery (central) pressures. SETTING: Clinical investigation in a university-based surgical intensive care unit. PATIENTS: Fourteen critically ill patients with presumed sepsis who received norepinephrine infusions at a rate of > or =5 microg/min. INTERVENTIONS: All patients were managed in accordance with our standard practice for presumed sepsis, which consisted of intravascular volume repletion followed by vasopressor administration titrated to a mean arterial pressure of > or =60 mm Hg. MEASUREMENTS AND MAIN RESULTS: Systolic and mean arterial pressures were significantly higher when measured from the femoral vs. radial site (p < .005). The higher mean arterial pressures enabled an immediate reduction in norepinephrine infusions in 11 of the 14 patients. No change in cardiac output or pulmonary artery occlusion pressure was noted after dose reduction. In the two patients in whom simultaneous recordings were made after discontinuation of norepinephrine infusions, equalization of mean arterial pressures was observed. CONCLUSIONS: Radial artery pressure underestimates central pressure in hypotensive septic patients receiving high-dose vasopressor therapy. Clinical management, based on radial pressures, may lead to excessive vasopressor administration. Awareness of this phenomena may help minimize adverse effects of these potent agents by enabling dosage reduction.

Bias↗
PubMed1997

Perioperative maintenance of normothermia reduces the incidence of morbid cardiac events. A randomized clinical trial.

OBJECTIVE: To assess the relationship between body temperature and cardiac morbidity during the perioperative period. DESIGN: Randomized controlled trial comparing routine thermal care (hypothermic group) to additional supplemental warming care (normothermic group). SETTING: Operating rooms and surgical intensive care unit at an academic medical center. SUBJECTS: Three hundred patients undergoing abdominal, thoracic, or vascular surgical procedures who either had documented coronary artery disease or were at high risk for coronary disease. OUTCOME MEASURE: The relative risk of a morbid cardiac event (unstable angina/ischemia, cardiac arrest, or myocardial infarction) according to thermal treatment. Cardiac outcomes were assessed in a double-blind fashion. RESULTS: Mean core temperature after surgery was lower in the hypothermic group (35.4+/-0.1 degrees C) than in the normothermic group (36.7+/-0.1 degrees C) (P<.001) and remained lower during the early postoperative period. Perioperative morbid cardiac events occurred less frequently in the normothermic group than in the hypothermic group (1.4% vs 6.3%; P=.02). Hypothermia was an independent predictor of morbid cardiac events by multivariate analysis (relative risk, 2.2; 95% confidence interval, 1.1-4.7; P=.04), indicating a 55% reduction in risk when normothermia was maintained. Postoperative ventricular tachycardia also occurred less frequently in the normothermic group than in the hypothermic group (2.4% vs 7.9%; P=.04). CONCLUSION: In patients with cardiac risk factors who are undergoing noncardiac surgery, the perioperative maintenance of normothermia is associated with a reduced incidence of morbid cardiac events and ventricular tachycardia.

Aged↗
PubMed1997

Beta-3 adrenoceptor (beta-3AR) expression in leptin treated OB/OB mice.

Leptin-deficient Ob/Ob mice are hypometabolic and have reduced fat cell expression of beta-3 adrenoceptors (ARs). To determine whether leptin repletion restores beta-3 AR number, C57BL/6J Ob/Ob mice were given exogenous leptin (5 mg/kg I.P. daily) for 21 days. Leptin administration reduced body weight from 43.1+/-3.7 to 34.1+/-3.7 g in Ob/Ob animals but had no effect on weight in wildtype animals. Body weight increased by 12% in Ob/Ob mice receiving saline. Beta-3 AR mRNA concentrations were markedly reduced in Ob/Ob animals at baseline. Leptin increased beta-3 AR mRNA to control levels in Ob/Ob mice, but had no effect in wildtype animals. Adipocyte leptin mRNA was increased by 400% in Ob/Ob mice and did not suppress with exogenous leptin administration, suggesting no direct feedback regulation of leptin synthesis. We speculate that restoration of beta-3 AR expression by repleting leptin may be important in correcting hypometabolism in Ob/Ob animals.

Animals↗
PubMed1997

Effects of clonidine on prolonged postoperative sympathetic response.

OBJECTIVE: Surgical trauma results in diffuse sympathoadrenal activation which is thought to contribute to perioperative cardiovascular complications in high-risk patients. Regional anesthetic and analgesic techniques can attenuate this "stress response" and reduce the occurrence rate of adverse perioperative events; however, their use in the postoperative period is logistically difficult and costly. The present study was undertaken to evaluate whether transdermal administration of the alpha2 adrenergic-receptor agonist, clonidine, can be used as a pharmacologic means of blunting the stress response throughout the perioperative period. DESIGN: Double-blind, placebo-controlled clinical trial in patients undergoing pancreatico-biliary surgery. SETTING: Operating rooms and surgical intensive care unit of a major university teaching hospital. PATIENTS: Forty patients scheduled for major upper abdominal surgery. INTERVENTIONS: Patients received either clonidine (0.2 mg orally and a clonidine TTS-3 patch the evening before surgery and 0.3 mg orally on call to the operating room) or matched oral and transdermal placebo. MEASUREMENTS AND MAIN RESULTS: Heart rate, systemic arterial blood pressure, plasma catecholamine, clonidine, interleukin-6 concentrations, and 24-hr urine cortisol and nitrogen excretion were measured the day before surgery and daily thereafter for 72 hrs postoperatively. Preoperative transdermal (and oral) clonidine administration resulted in therapeutic plasma clonidine concentrations throughout the perioperative period (1.54 +/- .07 [SEM] microg/mL). Clonidine reduced preoperative epinephrine and norepinephrine concentrations by 65%. Plasma catecholamine concentrations increased in both groups following surgery but were markedly lower throughout the postoperative period in patients receiving clonidine. Patients receiving clonidine had a reduced frequency rate of postoperative hypertension. Clonidine had no effect on plasma interleukin-6 concentration, urine cortisol excretion, or urine nitrogen excretion. No adverse effects of clonidine administration were observed. CONCLUSIONS: The combined administration of oral and transdermal clonidine effectively attenuated the catecholamine response to surgical stress throughout the postoperative study period. Clonidine administration produced specific sympatholytic effects, since other elements of the stress response were not attenuated. Undesirable side effects were not noted. The sustained sympatholytic effects we observed suggest that alpha2 adrenergic-receptor agonists may offer a pharmacologic means of modifying the sympathoadrenal response to injury, and may be useful in reducing perioperative complications.

Administration, Cutaneous↗
PubMed1997

Adrenergic, respiratory, and cardiovascular effects of core cooling in humans.

The adrenergic, respiratory, and cardiovascular responses to isolated core cooling were assessed in awake human subjects. Mild core hypothermia was induced by intravenous infusion of 30 or 40 ml/kg of cold saline (4 degrees C) on 2 separate days. A warm intravenous infusion (30 ml/kg, 37 degrees C) was given on a third day as a control treatment. Mean norepinephrine concentration increased 400% and total body oxygen consumption increased 30% when core temperature decreased 0.7 degrees C. Mean norepinephrine concentration increased 700% and total body oxygen consumption increased 112% when core temperature decreased 1.3 degrees C. Core cooling was associated with peripheral vasoconstriction and increased mean arterial blood pressure, whereas heart rate was unchanged. Plasma epinephrine and cortisol concentrations were unchanged during core cooling. There were no changes in any measured parameter with the warm infusion. These findings suggest that mild hypothermia induced by isolated core cooling is associated with an adrenergic response characterized by peripheral sympathetic nervous system activation without a significant adrenocortical or adrenomedullary response. The respiratory and cardiovascular responses to core cooling are characterized by a shivering-induced increase in metabolic rate, norepinephrine-mediated peripheral vasoconstriction, and increased arterial blood pressure.

Adolescent↗