A study of added costs of laparoscopic cholecystectomy based on surgery preference cards

Hospitals are pressured to cut expenses to generate a profit, but many current surgical procedures still fall below a "break-even" point. Laparoscopic cholecystectomy is a high-volume surgical procedure that can be profitable for hospitals if costs are reduced and complications minimized. Our limited liability corporation of independent surgical specialists examined the preference cards of ten surgeons who performed laparoscopic cholecystectomies in August 2000. We wished to determine whether these surgeons differed in their use of disposable equipment and devices for the same surgical procedure. All of the disposable equipment and devices studied were assigned a price by the hospital purchasing department that was representative of the hospital costs and not what was billed to the patient. The sum total of disposable instruments for a single operative case in which laparoscopic cholecystectomy was performed ranged from $92 to $637 (mean $333) depending on the preference of the surgeon. Our study points out the differences in expenses between surgeons. Maintaining this type of expense tracking can apply to other procedures and is a good place to start a surgeon-led and hospital-based cost-saving initiative.     

Central retinal artery occlusion by proxy: a cause for sudden blindness in an airline passenger

The use of gas media in ophthalmologic procedures is relatively commonplace. Scleral buckle and pneumatic retinopexy procedures using air-gas mediums are a widely accepted treatment for retinal detachment. We present a patient who had a scleral buckle with pneumatic retinopexy performed and subsequently flew in a commercial airliner 2 wk later. The patient experienced sudden blindness due to central retinal artery occlusion brought about by expansion of the air bubble when the aircraft reached cruise altitude and a cabin pressure of 8000 ft. The intraocular pressure exceeded the central artery pressure thereby collapsing the artery. The patient's symptoms were relieved when an onboard flight surgeon identified the problem and the cabin pressure was reset to 2000 ft. Flying after an ophthalmic procedure that incorporates intraocular gas may have complications due to the bubble expansion in accordance with Boyle's Law. The ophthalmologic surgeon must be diligent in forewarning patients of the potential complications of flying for weeks to months after a procedure that utilizes intraocular gas.     

A computational approach to control in complex cognition

Cognitive deficits associated with dorsolateral prefrontal cortex (DLPFC) damage are often most apparent in higher cognitive tasks that involve problem solving and managing multiple goals. However, computational models of prefrontal deficits on such tasks are difficult to construct. Problem solving is most naturally modeled with symbolic systems (e.g. production systems), but the effects of lesions are most naturally modeled with subsymbolic systems (neural networks). We show that when we adopt a simple and plausible model of neural computation, there is a natural and explicit mapping from symbolic, goal-driven cognition onto neural computation. We exploit this mapping to construct a neural network model that is capable of solving complex problems in the Tower of London task. The model leads to a specific hypothesis about the role of DLPFC in such tasks, namely, that DLPFC represents internally generated subgoals that modulate competition among posterior representations. When intact, the model accurately simulates the behavior of college students even on the most difficult problems. Furthermore, when the subgoal component is lesioned, it accurately simulates the behavior of prefrontal patients, including the fact that their deficits are most apparent on the most difficult tasks and that they have special difficulty with tasks that require inhibiting a prepotent response.     

Tertiary care centers: a strategy for fiscal survival

BACKGROUND: Managed care organizations use a variety of payment strategies to contract for high-end tertiary services with academic healthcare centers. We assessed the financial outcome of these strategies and attempted to identify those that maintain a balance between cost and reimbursement. METHODS: Patients admitted with an Injury Severity Score > or =16, hospital charges > or =$100,000, and a managed care organization as the payer were evaluated. RESULTS: A fixed reimbursement contract decreased reimbursement by 28% and negatively impacted the margin by 215%. The addition of a stop-loss provision to a fixed reimbursement contract is the best strategy to share the risk between payer and provider. If the fixed reimbursement strategy continued, the negative impact to the margin would have been $36,984 per patient. CONCLUSIONS: Fixed reimbursement strategies shift all the risk to the academic healthcare center. If volume, severity of illness, or cost is not controlled, they negatively affect the financial outcomes. The addition of a stop loss at $100,000 of charges paid at 40% of the entire claim most equitably distributes risk between the academic healthcare center and the managed care organization. It also excludes the negative impact of increasing severity of illness and volume and should induce cost control.     

Right heart dysfunction, pulmonary embolism, and paradoxical embolization during liver transplantation. A transesophageal two-dimensional echocardiographic study

In 16 adult patients, we performed continuous intraoperative two-dimensional transesophageal echocardiography (2DTEE) to help elucidate the mechanism of myocardial dysfunction that accompanies liver transplantation. In 4 of the 16 patients "paradoxical" motion of the interventricular septum consistent with right ventricular failure was seen. An additional three of the 16 patients showed right atrial enlargement and right-to-left deviation of the interatrial septum. Two patients showed evidence of paradoxical embolization (one of whom had right ventricular and right atrial enlargement), and a third patient (who had right atrial enlargement) embolized a large right atrial thrombus into the pulmonary circulation. Two-dimensional transesophageal echocardiography demonstrated that isolated right ventricular failure might account for some of the hemodynamic instability seen during liver transplantation. Venous, pulmonary, and paradoxical embolization of air and thrombi documented by transesophageal echocardiography likely contribute to right heart failure.