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K V Iserson

Publications and source records attributed to K V Iserson.

At least 73 records · Page 4Linked to original sources
PubMed1991

Federal advance directives legislation: potential effects on emergency medicine.

On December 1, 1991, a new federal law designed to increase public use of advance directives takes effect. After that date, health care facilities must provide written information about advance directives to all adult patients. This information must describe (1) the patient's rights to make medical care decisions under state statutes and case law, and (2) how patients can secure these rights within the scope of the provider's policies. The law also requires that institutions educate their staffs and the communities about advance directives and document the existence of any advance directive in the patient's medical record. The new federal law will benefit American society, U.S. health care, and the practice of emergency medicine. However, emergency physicians should anticipate that the law will provide not only benefits, but also some burdens. Many institutions will expect emergency department personnel to disseminate and explain the required information, and annotate the medical record. It is the specialty's responsibility to gather empirical data that can guide the use of advance directives in emergency departments.

Adult↗
PubMed1991

Core temperature measurement in hypovolemic resuscitation.

STUDY OBJECTIVES: Accurate core temperature measurement in severely hypovolemic patients can be difficult to achieve. We used a dog model to determine both a convenient method of measuring core temperature and the relative accuracy of the multiple sites. DESIGN: Prospective laboratory (animal model) study. SETTING: Operating suites in the Animal Care Department. PARTICIPANTS: Eight adult, anesthetized greyhound dogs. INTERVENTIONS: Continuous temperature monitoring by thermistors placed in the brain, central vein, tympanic membrane, bladder, rectum, esophagus, and subcutaneous tissue. Hemorrhage to 65% initial intravascular volume and autologous transfusion of cooled blood, during which serial temperature measurements were recorded. MEASUREMENTS AND MAIN RESULTS: The readings were analyzed with Pearson's correlation coefficient. Brain temperature correlated very well with tympanic membrane temperature throughout the course (r = .869, P less than .0005). Rectum, bladder, and esophagus also correlated well with brain. Central venous temperature, however, correlated poorly with temperatures at all other sites, reflecting the marked swings in intravascular temperature caused by cold transfusion. These wide variations were damped at the other sites. The best correlation of central venous temperature was with brain and bladder, although tympanic membrane correlation was fair. CONCLUSIONS: Because intravascular hypothermia appears to be the source of the arrhythmias and hemostatic abnormalities often seen during the early resuscitation of hypovolemic patients, our results suggest bladder or tympanic membrane as the initial temperature site. After the initial resuscitation, end organ (eg, brain) temperature is the most important and is most accurately reflected by tympanic membrane temperature.

Animals↗
PubMed1991

Getting advance directives to the public: a role for emergency medicine.

Advance directives are becoming more common in the health care system in the United States. Advance directives include "living wills," "durable powers of attorney for health care," "do not resuscitate orders," and the newer "medical directive." They are designed to allow individuals to determine the course of their medical care in the event that they are no longer able to transmit the information to their physician. The US Supreme Court's recent Cruzan decision increased the importance of these legal instruments by declaring that "clear and convincing" evidence may be required by states in order to terminate life support in a patient unable to express his wishes about care. Unfortunately, for many reasons, advance directives are often not completed by those who might desire them. Only 9% of Americans have executed advance directives. Emergency physicians have the opportunity to assist their patients in advance by disseminating advance directives to those who have contact with the emergency department: patients, family members, friends, health care workers, emergency medical services personnel, and police. A plan is suggested that includes education, the availability of advance directives, personnel available to help with completion of the documents, and immediate entry of the directive into a medical chart, if requested. This is in conformance with a recent policy adopted by the American College of Emergency Physicians.

Advance Directives↗
PubMed1991

Foregoing prehospital care: should ambulance staff always resuscitate?

Approximately 400,000 people die outside US hospitals or chronic care facilities each year. While there has been some recent movement towards initiating procedures for prehospital Do Not Resuscitate (DNR) orders, the most common situation in the US is that emergency medical systems (EMS) personnel are not authorized to pronounce patients dead, but are required to attempt resuscitation with all of the modalities at their disposal in virtually all patients. It is unfair and probably unrealistic for EMS personnel to have to make a determination of the validity of a non-standard prehospital DNR order (for example, a living will or a durable power of attorney for health care). Existing prehospital DNR protocols range from being very restrictive in the scope of patients allowed to participate and in their implementation, to those that are more liberal. Potential benefits of prehospital DNR orders include freeing up vital personnel and material for use by those who would more fully benefit, and alleviating the enormous emotional strain on patients, families, EMS personnel, and hospital medical staffs involved in unwanted resuscitations that only prolong the dying process. Given this, prehospital DNR orders present several legal and moral problems. These include proper patient identification, the nature of the document itself, precautions incorporated into a DNR system to prevent misuse, potential liability for EMS and hospital personnel, and potential errors in implementation. Functioning prehospital DNR systems need to include: 1) specific legislation detailing the circumstances in which such a document could be used, the wording of such a document, and protection from liability for those implementing the document's directives; 2) having the currently valid document immediately available to the EMS personnel or base station doctors; and 3) acceptable means of identifying the patient. Relatively few US jurisdictions as yet have a prehospital DNR order system, although it is an idea whose time is overdue. Society's imperative to use available technology has pushed us into a situation where a technique to save those with a potential to continue a meaningful and wanted existence is being used indiscriminately to prolong the agony of death.

Ambulances↗
PubMed1991

Rapid admixture blood warming.

A new technique of admixture blood warming allows rapid warming of packed red blood cells by the addition of heated saline. Each 4 degrees C unit of packed red blood cells is mixed with 250 ml of 70 degrees C saline. Diluted blood at 37 degrees C is ready for transfusion in less than 30 seconds.

Blood Transfusion↗
PubMed1991

What does Cruzan mean to the practicing physician?

The United States Supreme Court's recent decision in the Cruzan case declared that the states have broad powers to formulate their own rules in "right to die" cases. The Court held that competent adults have a constitutionally protected "liberty interest" that allows them to accept or refuse medical treatments. Since liberty interests are subject to rational state regulation, the narrow holding in Cruzan affirmed Missouri's authority to require a "clear and convincing" evidence standard to determine a patient's wishes before life-sustaining treatment could be withdrawn from a formerly competent adult now in a persistent vegetative state. For practicing physicians, some of the implications of Cruzan are as follows: (1) For competent adult patients, physicians should respect patient wishes regarding life-sustaining treatment. (2) Physicians also should discuss with competent patients their wishes for life-sustaining treatment at a future time, when a patient may no longer be able to participate in such decisions. (3) Physicians should record these wishes in a legally acceptable instrument that addresses two aspects of care that may arise in the future if the patient becomes incompetent. What would the patient want done? Who would the patient wish to designate as a surrogate or proxy? (4) For patients who are now incompetent, but for whom decisions must be made about life-sustaining treatment, physicians should focus on the previously expressed wishes of the patient rather than on the patient's current quality of life or on the wishes of the patient's family.

Advance Directives↗
PubMed1990

Rapid infusion.

Explore the source record for details and available documents.

Blood Transfusion↗
PubMed1990

Rapid admixture blood warming: technical advances.

The technique of rapid admixture blood warming of cold erythrocyte units is designed to warm erythrocyte units rapidly (less than 30 sec) while simultaneously providing saline for dilution. However, questions have been raised about the recommended use of a standard 250-ml bolus of 70 degrees C admixture saline, the uniformity and speed of blood unit warming, the difficulties inherent in keeping saline bags at 70 degrees C, and the safety of the methodology. To answer these questions, a series of tests were performed and modifications of the technique were introduced. The mean weight of 1000 successive units of erythrocytes for adult infusion was 305 g (range 220 to 410). The maximum temperature was 44 degrees C, using an internal temperature probe (1-cm temperature gradations; 2-sec recording intervals) when the smallest unit was admixed with a 250 ml 70 degrees C saline bolus; the largest unit had a minimum temperature of 30 degrees C. Plasma Hgb, osmotic fragility, and K of the minimum size erythrocyte unit showed no significant deviation from its control. Both thermographic photographs and the internal temperature recordings of the erythrocyte units demonstrated that solely due to fluid turbulence, uniform mixing occurs within approximately 30 sec of beginning the admixture process. Inverting the blood units caused a thermal layering of fluids and an unacceptable maximum blood temperature of 50 degrees C. There was no difference between the mixing time or efficacy in the presence of standard or large-bore iv tubing or additional in-line filters. Volumes of the 250-ml saline bags for admixture decreased markedly with deviations in electrolyte composition after greater than 2 wk at 70 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Transfusion↗
PubMed1988

Red blood cell survival following admixture with heated saline: evaluation of a new blood warming method for rapid transfusion.

We studied the in vivo survival of packed red blood cells (RBC's) which had been warmed using the new technique of admixture with high-temperature saline. Packed RBC's from five normal male subjects were stored in CPDA-1 at 4 degrees C for 14 days. They were then warmed via admixture with an equal amount of saline heated to 70 degrees C. Osmotic fragility, and supernatant hemoglobin and potassium levels of the warmed RBC's were not significantly different from baseline values. Aliquots of the warmed RBC's were labeled with 51Chromium and transfused into autologous donors. Mean radiolabeled RBC survival at 24 hours was 90.2% (S.D. 6.2%), and mean radiolabeled RBC survival time was 25.3 days (S.D. 2.7 days). These results are within the normal range for RBC's stored for 14 days. This study suggests that RBC survival after transfusion is not impaired by admixture blood warming using saline at 70 degrees C.

Blood↗