airwayDeposition of aerosol particles in the airways is mainly due to four mechanisms: inertial impaction, gravitational sedimentation, and Brownian and turbulent diffusion. Since these mechanisms are closely related to the aerodynamics within the airways, both breathing pattern and airway geometry greatly influence the regional and total aerosol deposition. Effects of variations of the breathing pattern have been well studied, but there have been few investigations of the geometric effects.

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bronchogenic carcinomaFor the treatment of bronchogenic carcinoma, surgery offers a considerably better chance of cure relative to radiation therapy. However, surgical resection is possible in only 20 to 25 percent of patients at presentation, and of these, five-year survivals following curative resection of 10 to 40 percent depend mainly on degree of lymph node involvement.

The overall five-year survival remains at 10 to 12 percent. Up to 90 percent of patients will require palliative therapy of the effects of their tumors. Many of these will have continuing symptoms due to the effects of the primary tumor on the airway, such as hemoptysis, dyspnea, or distal infection. External beam radiation is the mainstay of palliative therapy of these predominantly central tumors. However, the dose of external radiotherapy is limited by the tolerance of surrounding normal tissue and does not therefore lend itself to repeated use. Furthermore, while external beam radiation is effective in 84 percent of patients with hemoptysis, 61 percent with chest pain and 60 percent with dyspnea, resolution of atelectasis was achieved in only 23 percent of patients. We are reporting on a technique in use at this institution for management of the effects of the primary tumor on the airway. A 198Au radiation source is implanted into the tumor mass under local anesthesia via the fiberoptic bronchoscope (FOB). Repeated applications may be performed as indicated by clinical and roentgeno-graphic follow-up.

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Withholding and Withdrawal of Life Support from Critically Ill Patients: Medical Opinions Regarding Withholding or Withdrawing SupportMedical Opinions Regarding Withholding or Withdrawing Support
Most of the court cases cited regarding withholding or withdrawal of life support were brought by patients or their proxies against physicians and medical institutions for failing to withhold or withdraw support. Furthermore, most of the legislation cited earlier has been advanced by the legal and not the medical profession. Whatever the reasons for this situation, it is widely perceived that the medical profession has occupied a right-to-life at all costs position in defiance of growing public sentiment for patient autonomy and the right to die. Yet despite this perception, physicians have become increasingly outspoken in their desire to withhold and withdraw life support in certain circumstances through the Presidents Commission, personal writings, and position papers in medical literature. Among the most important of these statements have been “Optimum care for hopelessly ill patients,” “The physicians responsibility towards hopelessly ill patients,” and “Initiating and withdrawing life support,” all of which were published in the New England Journal of Medicine. These papers argue persuasively for withholding or withdrawing therapies ranging from mechanical ventilation to fluids and nutrition from patients with terminal illnesses and irreversible coma or the persistent vegetative state, especially if the families agree. Read the rest of this entry »

Use of Advance Directives
In all the cases cited earlier, the courts have endorsed the use of patients’ previously stated wishes regarding life support and the validity of patient proxies in articulating these wishes or deciding for the patients when their wishes are not known. In parallel with these judicial actions, private individuals have chosen to communicate their wishes through living wills. These documents, which may be classified as instructional directives, are least effective when their language is vague and they are applied to patients with uncertain prognoses. Nevertheless, living wills can add greatly in clinical decision making. Unfortunately, the documents are of dubious legal reliability when not legislated by the respective state; in Florida, the first State Appellate Court to review the issue of living wills in, In the Matter of Francis Landy (1983), ruled that a living will that was not approved by the state legislature cannot be the basis for withholding or withdrawing life support. Read the rest of this entry »

Withholding and Withdrawal of Life Support from Critically Ill Patients: TherapiesThe celebrated case of Barber v Superior Court (1983) confirmed the utility of “substituted judgment” and also answered the question of physician liability in withholding or withdrawing life support. This case involved two California physicians who performed surgical closure of an ileostomy on Mr. Herbert, who subsequently suffered cardiopulmonary arrest. Five days later they determined that his coma was irreversible and, with the consent of his family, withdrew not only mechanical ventilation but also intravenous fluids and nutrition. Although the family found no fault with this at the time, the physicians were accused of murder by a district attorney After the case was heard by several courts, the California Court of Appeals ruled that the physicians had not failed to perform their duty because they considered it medically futile to continue life support. Read the rest of this entry »

The American judicial system, which has supported the concept of brain death as described earlier, also has been instrumental in shaping public attitudes and social policy in the area of withholding or withdrawing support from patients who are not brain dead. In the process, the courts have underscored the importance of privacy and the right to refuse treatment. They have also contributed to the concept that human life is more than a biologic process, defined how therapies may or may not benefit patients, argued against a distinction between withholding and withdrawal of support, and established guidelines for how support may be withheld or withdrawn. Read the rest of this entry »

Withholding and Withdrawal of Life Support from Critically Ill Patients: CNSThis concept was appealing, because it recognized the integrative function of the central nervous system (CNS), without which there can be no breathing or heartbeat. The legal propriety of brain death was upheld in the case of Tucker v Lower (1972), in which a Virginia court found that physicians who removed Bruce Tucker from a ventilator in order to transplant his heart were not guilty of a wrongful determination of death. Since then, the Presidents Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research has recommended a uniform determination of death statute; 37 states plus the District of Columbia have passed brain death statutes, and several of the nonstatute states have acknowledged the propriety of withholding or withdrawing life support from the brain dead. Furthermore, policies of “required request” were enacted in 1986 in California, Oregon, and New York requiring that physicians bring up the issue of organ donation with the families of patients with brain death. Read the rest of this entry »

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