Taking the dread out of annual performance evaluations

Many employees and managers alike dread annual performance evaluations. However, there is a way to get past the "dread" factor. Annual performance evaluations can be a positive experience and even motivational. They can be a time for affirming good work of the past year and planning together what will be accomplished in the year to follow. By keeping employees informed of the larger picture, helping them to see how they fit in, involving them in setting performance objectives, dealing with performance problems as they arise, and noticing when they have achieved their objectives can make evaluation a positive experience.     

Presenting statistical uncertainty in trends and dose-response relations.

When one estimates the effects of a polytomous exposure, it is common practice to express all effects relative to a baseline or reference level. Certain authors have challenged this practice and proposed alternatives, which we review here. One alternative, the "floating absolute risk" method, can supply useful statistics and trend graphs, but it does not yield valid confidence intervals for relative risks. All categorical methods have further shortcomings when the exposure is continuous, however. These shortcomings can be addressed by plotting or tabulating confidence limits for points on a flexible curve fitted to the uncategorized data.     

Initial resuscitation volume in uncontrolled hemorrhage: effects on organ function

Conventional resuscitation of hypovolemia due to hemorrhage has consisted of aggressive fluid administration. Recent studies have suggested that surgical control of bleeding before fluid resuscitation might improve early survival. The effects of limited resuscitation on organ function have not been assessed in these studies. We developed a model of moderate intraperitoneal hemorrhage designed to evaluate long-term end-organ function after various resuscitation protocols. Male Sprague-Dawley rats underwent ketamine anesthesia, followed by placement of femoral artery and vein lines. Intraperitoneal hemorrhage was induced by division of distal branches of the ileocolic artery and vein. After 5 minutes of bleeding, the animals were randomized to one of three resuscitation groups: Group 1 received no fluid resuscitation before surgical control of the hemorrhage; Group 2 received 0.5 mL of lactated Ringer's solution (LR) every 5 minutes for a mean arterial pressure (MAP) of less than 80 mm Hg; Group 3 received 2.0 mL of LR every 5 minutes for a MAP of less than 80 mm Hg. In all three groups, after 20 minutes, the bleeding was surgically controlled. All rats were then resuscitated with LR to a MAP of 80 mm Hg. The intravascular lines were removed, and the rats were allowed to recover from anesthesia and were returned to animal holding. On the 7th day, survivors were sacrificed, and their blood was assayed for hematocrit and serum levels of bilirubin, alanine aminotransferase, urea nitrogen, and creatinine. Kidneys, lungs, and liver were harvested for microscopic examination. Survival was lower in Group 2 than in the other groups (90%, 60%, and 100%, respectively; P = 0.04), but all deaths occurred within 3 hours of hemorrhage and were due to either hypovolemia or anesthetic complications. No histologic abnormalities were identified in the livers of the animals that survived, but pulmonary atelectasis and mild-to-moderate renal tubular necrosis were identified uniformly. No histologic differences could be discerned between the groups. Hematocrit and indices of liver and renal function were similar in all groups, and no animal developed organ dysfunction. In this model of moderate uncontrolled intraperitoneal hemorrhage, the volume of fluid resuscitation, or the absence of resuscitation, had an inconsistent effect of 7-day survival and did not influence function or histologic appearance of the liver, lungs, or kidneys 7 days after hemorrhage.     

Sequestration of type VI collagen in the pericellular microenvironment of adult chrondrocytes cultured in agarose

The chondron represents the chondrocyte and its pericellular microenvironment and plays an important role in the progression of osteoarthritis. Type VI collagen is preferentially localized in the pericellular microenvironment of adult articular cartilage and increases during osteoarthritis. In this study, we characterized the pericellular sequestration of type VI collagen in long-term chondrocyte-agarose cultures, and assessed the action of interleukin-1 on type VI collagen deposition and assembly. Immunohistochemical and biochemical analysis showed that cultured chondrocytes initiate type VI collagen sequestration immediately upon plating and continue pericellular matrix sequestration in a time dependent manner. Confocal microscopy confirmed the cell surface localization and pericellular accumulation of type VI collagen, while image analysis identified a 'cargo-net like' organization of type VI collagen around each chondrocyte. Quantitative analysis revealed a primary phase of rapid cell division and low levels of type VI collagen sequestration, followed by a secondary phase of relative growth stability and high levels of type VI collagen deposition. Interleukin-1 treated cultures showed increased sequestration and retention of type VI collagen in an expanded microenvironment surrounding the chondrocytes. The data suggests a role for type VI collagen in the differentiation of the pericellular microenvironment in vitro. The increased type VI collagen sequestration promoted by interleukin-1 was consistent with previous studies on osteoarthritic cartilage, and implies a functional role for type VI collagen in the chondron remodeling associated with cartilage degradation.     

The diagnosis of aortoiliac disease. A noninvasive femoral cuff technique.

An inexpensive femoral "cuff" developed in this noninvasive vascular laboratory allows pulse volume recordings and systolic pressure measurements of the femoral arteries. Using the parameters 1) femoral/brachial systolic pressure ratio, 2) wave amplitude, and 3) status of the dicrotic notch for assessment of results, it was found that the cuff correctly identified 59 of 62 limbs with at least 50% aortoiliac stenosis, with only two false-positive results, for an accuracy of 97%. The high, wide thigh cuff identified 57 of the 62 limbs, but had 45 false-positive results (77% accuracy). Use of the femoral "cuff" has refined the ability to identify the anatomic location of significant arterial stenoses in the lower extremities.     

A comparison of the myocardial metabolic and haemodynamic changes produced by propofol-sufentanil and enflurane-sufentanil anaesthesia for patients having coronary artery bypass graft surgery

The purpose of this study was to compare propofol-sufentanil with enflurane-sufentanil anaesthesia for patients undergoing elective coronary artery bypass graft (CABG) surgery with respect to changes in (1) haemodynamic variables; (2) myocardial blood flow and metabolism; (3) serum cortisol, triglyceride, lipoprotein concentrations and liver function; and (4) recovery characteristics. Forty-seven patients with preserved ventricular function (ejection fraction greater than 40%, left ventricular end diastolic pressure less than or equal to 16 mmHg) were studied. Patients in Group A (n = 24) received sufentanil 0.2 microgram.kg-1 and propofol 1-2 mg.kg-1 for induction of anaesthesia which was maintained with a variable rate propofol (50-200 micrograms.kg-1.min-1) infusion and supplemental sufentanil (maximum total 5 micrograms.kg-1). Patients in Group B (n = 23) received sufentanil 5 micrograms.kg-1 for induction of anaesthesia which was maintained with enflurane and supplemental sufentanil (maximum total 7 micrograms.kg-1). Haemodynamic and myocardial metabolic profiles were determined at the awake-sedated, post-induction, post-intubation, first skin incision, post-sternotomy, and pre-cardiopulmonary bypass intervals. Induction of anaesthesia produced a larger reduction in systolic blood pressure in Group A (156 +/- 22 to 104 +/- 20 mmHg vs 152 +/- 26 to 124 +/- 24 mmHg; P less than 0.05). No statistical differences were detected at any other time or in any other variable including myocardial lactate production (n = 13 events in each group), time to tracheal extubation and time to discharge from the ICU. We concluded that, apart from hypotension on induction of anaesthesia, propofol-sufentanil anaesthesia produced anaesthetic conditions equivalent to enflurane-sufentanil anaesthesia for CABG surgery.     

Cerebrospinal fluid shunt function and hydrocephalus in the pediatric age group: a radiographic/clinical correlation.

Eighty-four pediatric patients were evaluated clinically and radiographically on 112 separate admissions for suspected increased intracranial pressure and possible shunt malfunction. The shunt system was tested clinically in each patient and correlated with the ventricular size as determined by CT. Of the patients with enlarged ventricles, 87% had an improperly functioning shunt and 13% had a normally functioning shunt. Of the patients with normal or small ventricles, 93% had a normally functioning shunt. Thus the "false negative" rate was 4% (small ventricles with a nonfunctioning shunt) and the "false positive" rate was 13% (large ventricles with a functioning shunt).     

Surgical management of malignant melanoma using dynamic lymphoscintigraphy and gamma probe-guided sentinel lymph node biopsy: the Emory experience

Sentinel lymph node (SLN) biopsy is revolutionizing the surgical management of primary malignant melanoma. It allows accurate nodal staging which targets patients who may benefit from regional lymphadenectomy and systemic therapy. This is a retrospective review of patients treated at Emory University for stage I and II malignant melanoma with gamma probe-guided SLN biopsy from 1/1/94 to 6/30/98. Three hundred sixty patients (males 228, females 132) were identified. Primary melanoma sites included: head and neck 58, trunk 148, and extremities 154 (upper 71, lower 83). Primary tumor staging was T1 9, T2 134, T3 153, and T4 64. SLNs were successfully identified in 99.7 per cent of patients and 98.9 per cent of nodal basins mapped. In 275 (76.6%) cases a single draining nodal basin was identified. In 84 (23.3%) cases there were multiple draining nodal basins. Positive SLNs were identified in 63 patients (17.5%). SLN positivity by tumor staging was T1 0 per cent, T2 9.0 per cent, T3 22.2 per cent, and T4 26.6 per cent. The overall recurrence rate was 11.9 per cent. Recurrences by SLN status were SLN+, 27 per cent, and SLN-, 8.8 per cent. Regional recurrence occurred in 7 (2.4%) of the 297 with negative SLN biopsies and 7 (11.1%) of the 63 with positive SLN biopsies. Dynamic lymphoscintigraphy and gamma probe-guided SLN localization was successful in more than 98 per cent of cases. Patients with negative SLN biopsies have a low risk of recurrence.