Resident teaching versus the operating room schedule: an independent observer-based study of 1558 cases

Efforts to improve operating room efficiency may threaten clinician training. Therefore, we designed a prospective, observational study to determine the actual time spent teaching anesthesiology residents during the interval from patient-on-table to skin incision and to determine whether anesthesia teaching in the peri-induction period increases the time to surgical incision. This study was conducted in an inpatient operating room suite of a tertiary academic medical center. Of 1558 cases examined, 75% had an element of teaching (mean percent teaching per case = 46.4). A 33% decrease in teaching occurs when the attending anesthesiologist concurrently directed care in 2 rooms (P < 0.001). The percent teaching significantly increased as a function of ASA physical status classification and time of day of surgical case (P = 0.001). Teaching accounted for a mean increase of time to incision of 4.5 +/- 3.2 min, but represented only 3% of the mean surgical case length (207 +/- 132 min). We conclude that teaching occurs in the majority of cases in the operating room and although it contributes to increased time to incision, this increase is insignificant compared with the time required to complete the surgical procedure.     

Use of rhDNase therapy and costs of respiratory-related care in patients with cystic fibrosis

OBJECTIVE: To assess the relationship between level of use of recombinant deoxyribonuclease I (rhDNase) therapy and costs of respiratory-related care in patients with cystic fibrosis. DESIGN: Retrospective, cohort study using healthcare claims data from a large New England health insurer. PATIENTS: All cystic fibrosis patients five years of age and older who began therapy with rhDNase in 1994 (the year it was first marketed in the US). Healthcare claims were compiled for six months prior to first receipt of rhDNase (pretreatment) and for 30 months subsequently (follow-up). Patients were stratified according to their level of rhDNase use during follow-up, based on whether it was above or below the median number of therapy days for the sample. MAIN OUTCOME MEASURES: Costs of rhDNase, all antibiotics, and all respiratory-related outpatient (physician, home health, hospital outpatient) and inpatient care were included. All costs were expressed on an annualized basis. RESULTS: Twenty-four patients with cystic fibrosis who began treatment with rhDNase in 1994 met all entry criteria; the median number of therapy days over a 30-month period was 355. Among patients with low (i.e., below the median) rhDNase use (n = 12), mean +/- SD annualized costs of respiratory-related care increased by almost $17,000 between pretreatment and follow-up, from $29,251 +/- $37,919 to $46,109 +/- $40,944. Among high-use patients (n = 12), costs decreased by approximately $2500, from $37,178 +/- $48,476 to $34,592 +/- $22,591. The change in both groups was accounted for primarily by a change in the number of respiratory-related hospitalizations. CONCLUSIONS: Prolonged use of rhDNase may reduce costs of respiratory-related care in patients with cystic fibrosis; further study is required, however, to confirm these findings.     

Hypocellular myelodysplastic syndromes (MDS): new proposals

Summary. To determine whether hypocellular MDS differs from normo/hypercellular MDS, we attempted to identify hypocellular MDS cases either by correcting the bone marrow (BM) cellularity by age (28 patients) or by using a single arbitrary value of BM cellularity (25 patients) and compared these two groups of hypocellular cases to the normo/hypercellular MDS cases (72 patients). 18 patients were common to both hypocellular groups. Patients with hypocellular MDS in both of these selected groups have similar features with regard to age and sex distribution, peripheral blood and bone marrow parameters, FAB subtypes, karyotypes, leukaemic transformation, and survival. However, the median age of patients in < 30% BM cellularity group was higher than those patients in the age-corrected group (69 years v 62 years). The selection of < 30% cellularity excluded 10 cases in the age group < 70 years but included another seven patients in the age group of > 70 years. However, correction of BM cellularity by age revealed that those included patients (selected for < 30% cellularity) who had normocellular BM by their age. Therefore we recommend the age-correcting grouping to ensure comparable series for comparison, for response to treatment, and survival. Finally, BM cellularity does not appear to be an important factor on prognosis in MDS, because patients with hypocellular MDS in both selected groups have similar prognosis to those with normo/hypercellular MDS patients.     

Effects of human 17 kDa interleukin 1, 25-31 kDa thymocyte stimulating activity and the 6-9 kDa interleukin 1 inhibitor on calcium release in the newborn murine calvarial assay

The effects of human monokines on calcium release from cultured newborn murine calvarium were studied. Highly purified interleukin 1 (IL-1) (17 kDa) and recombinant IL-1 beta in the concentration range 0.2-20 U/ml released significant amounts of calcium. Mean resorption indices (RI) at 0.2 U/ml were 1.28 and 1.49, and at 20 U/ml, were 1.82 and 1.72, respectively. Calcium release was abrogated by the cyclooxygenase inhibitor piroxicam. Thymocyte stimulating activity (TSA) 25-31 kDa alone at 0.14 U/ml released calcium in a prostaglandin dependent manner with a mean RI of 2.13, a significantly greater calcium release than that obtained by 17 kDa IL-1 at 20 U/ml. The 6-9 kDa inhibitor of IL-1 induced thymocyte proliferation alone also released calcium in a prostaglandin dependent manner with a mean RI of 2.29 at 200 inhibitory U/ml. Addition of 6-9 kDa IL-1 inhibitor to the 25-31 kDa material did not significantly change the calcium release, whereas addition of the inhibitor to 17 kDa IL-1 produced a significant increase in calcium release.     

The action of Chrysaora quinquecirrha (sea nettle) toxin in inhibiting the intestinal transport of glucose in the golden hamster.

J. Watrous and E. P. Walsh. The action of Chrysaora quinquecirrha (sea nettle) toxin in inhibiting the intestinal transport of glucose in the golden hamster. Toxicon14, 179–183, 1976—Experiments were conducted to study the effects of Chrysaora quinquecirrha toxin on the sodium-linked transport of glucose in hamster small intestine. Everted strips of tissue were exposed to whole toxin while incubating in buffers with various glucose or sodium concentrations. In all cases, the per cent depression of glucose uptake was nearly identical, indicating non-competitive inhibition of the active transport process. It is suggested that Chrysaora nematocyst toxin alters a property of the brush border membrane, thereby increasing its permeability to Na⁺ ions.     

Behavioral correlates of human hippocampal delta and theta oscillations during navigation

Previous rodent studies demonstrate movement-related increases in theta oscillations, and recent evidence suggests that multiple navigationally relevant variables are reflected in this activity. Human invasive recordings have revealed movement-related modulations in delta and theta activity, although it is unclear whether additional behavioral variables are responsible for modulating this neural activity during navigation. We tested the role of delta and theta oscillations during navigation by addressing whether spatial-related processing, in addition to speed and task variables, modulates delta and theta activity. Recording from 317 hippocampal intracranial electrodes in 10 patients undergoing seizure monitoring, we observed increasing delta and theta power with increasing virtual speed at significantly more electrodes than would be expected by chance, replicating previous findings in nonhuman mammals. Delta and theta power were more consistently modulated, however, as a function of spatial view, including when subjects looked at stores in the virtual environment both to find a relevant goal or for spatial updating. A significantly larger proportion of electrodes showed view-related effects than speed-related modulations. Although speed, task, and spatial view affected delta and theta activity, individual electrodes were most frequently modulated by only one variable, rather than a combination of variables. These electrodes likely sampled independent delta and theta generators, which reflected movement-related and allocentric processing, respectively. These results extend previous findings in nonhuman mammals and humans, expanding our knowledge of the role of human hippocampal low-frequency oscillations in navigation.