PubMed Health⌕ Search

Biomedical subjects

Keith B Isaacson

Publications and source records attributed to Keith B Isaacson.

5 recordsLinked to original sources

Reorganizing patient care and workflow in the operating room: a cost-effectiveness study.

BACKGROUND: Many surgeons believe that long turnover times between cases are a major impediment to their productivity. We hypothesized that redesigning the operating room (OR) and perioperative-staffing system to take advantage of parallel processing would improve throughput and lower the cost of care. METHODS: A state of the art high tech OR suite equipped with augmented data collection systems served as a living laboratory to evaluate both new devices and perioperative systems of care. The OR suite and all the experimental studies carried out in this setting were designated as the OR of the Future Project (ORF). Before constructing the ORF, modeling studies were conducted to inform the architectural and staffing design and estimate their benefit. In phase I a small prospective trial tested the main hypothesized benefits of the ORF: reduced patient intra-operative flow-time, wait-time and operative procedure time. In phase II a larger retrospective study was conducted to explore factors influencing these effects. A modified process costing method was used to estimate costs based on nationally derived data. Cost-effectiveness was evaluated using standard methods. RESULTS: There were 385 cases matched by surgeon and procedure type in the retrospective dataset (182 ORF, 193 standard operating room [SOR]). The median Wait Time (12.5 m ORF vs 23.8 m SOR), Operative Procedure Time (56.1 m ORF vs 70.5 m SOR), Emergence Time (10.9 m ORF vs 14.5 m SOR) and Total Patient OR Flowtime (79.5 m ORF vs 108.9 m SOR) were all shorter in the ORF (P < .05 for all comparisons). The median cost/patient was $3,165 in the ORF (interquartile range, $1,978 to $4,426) versus $2,645 in SORs (interquartile range, $1,823 to $3,908) (P = ns). The potential change in patient throughput for the ORF was 2 additional patients/day. This improved throughput was primarily attributable to a marked reduction in the non-operative time (ie, those activities commonly accounting for "turnover time") rather than facilitation of faster operations. The incremental cost-effectiveness ratio of ORF was $260 (interquartile range, $180 to $283). CONCLUSION: The redesigned perioperative system improves patient flow, allowing more patients to be treated per day. Cost-effectiveness analysis suggests that the additional costs incurred by higher staffing ratios in an ORF environment are likely to be offset by increases in productivity. The benefits of this system are realized when performing multiple, short-to-medium duration procedures (eg, <120 m).

Cost-Benefit Analysis↗

Cost-effectiveness of uterine artery embolization and hysterectomy for uterine fibroids.

PURPOSE: To compare the cost-effectiveness of uterine artery embolization (UAE) with that of hysterectomy for women with symptomatic uterine fibroids. MATERIALS AND METHODS: The authors developed a decision model to compare the costs and effectiveness of UAE and hysterectomy. In the model, a cohort of women aged 40 years with a diagnosis of uterine fibroids and no desire for future pregnancy was followed up until menopause. The analysis was performed from a societal perspective, including all costs and effects, regardless of who incurs them. Transition probability and quality-of-life estimates were obtained from the literature and a gynecologist, whereas costs (in 1999 U.S. dollars) were estimated by using rates of Medicare reimbursement for hospital costs and physician fees. Sensitivity analyses of key estimates were performed. Results were expressed in costs per quality-adjusted life-year (QALY). RESULTS: UAE was more effective (8.29 vs 8.18 QALYs) and less expensive (US dollars 6916 vs US dollars 7847) than hysterectomy. Cost-effectiveness results, with the exception of quality-of-life data, were robust to changes in most model assumptions. When the quality-of-life adjustment was eliminated, the two procedures were equally effective. CONCLUSION: UAE is a cost-effective alternative to hysterectomy across a wide range of assumptions about the costs and effectiveness of the two procedures. However, the study results were sensitive to changes in quality-of-life values.

Cost-Benefit Analysis↗

Signal transduction pathways involved in macrophage migration induced by peritoneal fluid chemotactic factors in stages I and II endometriosis.

OBJECTIVE: To explore the role of G-protein coupled signaling pathways in activation of macrophage migration in endometriosis stages I and II. DESIGN: Case controlled study. SETTING: University hospital. PATIENT(S): Fifteen patients undergoing laparoscopy for elective sterilization (n = 5) or for diagnosis of endometriosis stages I and II associated with infertility (n = 10). INTERVENTION(S): Peritoneal fluid samples were collected during laparoscopy. MAIN OUTCOME MEASURE(S): Macrophage migration induced by peritoneal fluid from patients with endometriosis stages I and II (PF SI-II) and potential G-protein coupled receptors and second messengers involved in macrophage activation. RESULT(S): Potential G-protein coupled receptors and second messengers involved in macrophage activation were evaluated after incubation of U-937 cells differentiated into macrophages with inhibitors of phospholipase A and C, adenylate cyclase, and protein kinase A and C. Macrophage chemotactic activity induced by PF SI-II was inhibited in the presence of a phospholipase C and A2 inhibitor (IC50= 30 microM) and after treatment with myristoylated protein kinase C peptide inhibitor (50 nM). An increase in inositol phosphate (IP3) was also observed in macrophages exposed to PF SI-II. Activation of multiple G-proteins in macrophages was examined after exposure of cells to PF SI-II in the presence and absence of Bordettela pertussis and cholera toxins. No effect on macrophage migration was observed. CONCLUSION(S): Macrophage chemotaxis induced by PF SI-II appears to involve activation of pertussis toxin-insensitive G-protein coupled receptors in macrophages. Our data suggest that these events lead to subsequent activation of phospholipases followed by generation of IP3 and potential mobilization of intracellular Ca2+. Subsequent phosphorylation of target proteins by protein kinase C may regulate the chemotactic responses. The adenylate cyclase pathway does not appear to play a role in this process.

Ascitic Fluid↗

A pilot study examining the frequency and quantity of gas embolization during operative hysteroscopy using a monopolar resectoscope.

STUDY OBJECTIVE: To assess baseline frequency of gas embolization during standard monopolar resectoscopic surgery. DESIGN: Prospective, nonrandomized, observational study (Canadian Task Force classification II-2). SETTING: Tertiary care medical center. PATIENTS: Eleven women and three controls. INTERVENTION: Operative hysteroscopy. MEASUREMENTS AND MAIN RESULTS: Echocardiography and serum studies were performed to detect bubble formation in the inferior vena cava, hepatic veins, and right heart. Gas bubbles were present in the hepatic veins or right heart in 10 patients and no controls. No patients had changes in coagulation profile and only one had clinical changes during surgery. CONCLUSION: Gas bubbles can been detected by echocardiography in most patients undergoing resectoscopic surgery in the uterus. Clinical significance may relate to anatomic variations as well as to gas bubble content and volume.

Adult↗