Diarrhea associated with lorazepam solution in a tube-fed patient.

A 43-year-old patient with adult respiratory distress syndrome, alcoholic hallucinosis, and delirium required significant amounts of lorazepam, morphine, and midazolam for management of agitation and increased peak airway pressures. Broad-spectrum antibiotics and intermittent pancuronium therapy were instituted. A nasoenteral feeding tube was placed for nutrition and medication administration during mechanical ventilation. Tube feedings were well tolerated except for intermittent bouts of large amounts of diarrhea. Clostridium difficile culture and toxin results were negative. Lorazepam and morphine administration were converted from the IV to enteral route to decrease the amount of fluid administered. The tube feeding was changed to an electrolyte rehydration solution and eventually discontinued. A search for drug-related contributing factors to the diarrhea revealed polyethylene glycol present in the lorazepam solution. It was postulated that this could be a contributing cause to the diarrhea. The lorazepam solution was changed to enterally administered crushed tablets with subsequent resolution of diarrhea.

Improving pain management after total joint replacement surgery.

PURPOSE: To test the effects of implementing evidence-based postoperative pain management content and strategies on patient, provider (nurse and physician), and fiscal outcomes. SAMPLE: 118 patients, 57 before and 61 after implementation, having total knee replacement (TKR) (54%) and total hip replacement (THR) (45%), and 28 orthopaedic nurses. METHODS: A research utilization approach with a pretest/posttest design was used. Independent variables (interventions) included evidence-based pain management content, education of care providers and patients, and system changes at the point of care. Dependent variables (outcomes) were patient perception of the postoperative pain experience, provider practice patterns, and length of stay (LOS). FINDINGS: The hypotheses of decreased provider use of meperidine and increased use of hydromorphone, i.v. route, pain plans of care, and nurse knowledge were supported. LOS was significantly reduced. The patient hypotheses decreased pain intensity and side effects and increased satisfaction and function were not supported. CONCLUSION: Methodical implementation of evidence-based pain management information changed practice and fiscal outcomes. Improvement in the patient perception of pain management was more difficult to achieve.

Postmortem changes and pharmacokinetics: review of the literature and case report.

OBJECTIVE: To review the mechanisms and sequence of events that occur during ischemia and cell death and following death of the human body. The impact of these postmortem events on the distribution and pharmacokinetic behavior of drugs is described. The case study presented illustrates a possible situation where such postmortem changes could have affected the pharmacokinetics of procainamide. DATA SOURCES: English-language journal articles and reference texts identified from pertinent data sources. DATA SYNTHESIS: Postmortem changes in the human body begin at the cellular level with the onset of ischemia. As the length of time of ischemia increases and death ensues, more changes occur and lead to deterioration in tissue and organ function. These changes may affect the pharmacokinetic and distribution behavior of certain drugs. Drugs particularly affected are those whose distribution is dependent on molecular size, lipophilicity, pH, energy-dependent transport, and tissue binding. Such drugs include the tricyclic antidepressants, digoxin, and cimetidine. Other drugs with similar characteristics, such as procainamide, may also demonstrate like changes in distribution and pharmacokinetics. CONCLUSIONS: When measuring drug concentrations after death, it is important to consider the phenomenon of postmortem redistribution. Postmortem drug concentrations may not be a true reflection of antemortem concentrations and as a result, wrong conclusions could be made about the cause of death. More studies characterizing the postmortem distribution and pharmacokinetic characteristics of specific drugs are necessary.

Oxygen homeostasis: theory, measurement, and therapeutic implications.

The ultimate goal of therapeutic intervention in a critically ill patient is to maintain oxygen homeostasis where delivery of oxygen to the cells is greater than, or at least equal to, the oxygen demand of the cells. Oxygen demand varies from organ to organ. Total body oxygen demand is the sum of all oxygen required by all tissues and organs for aerobic cellular function. Oxygen consumption (VO2) is the quantity of oxygen actually used by the cells. VO2 may be calculated if the values of cardiac output (CO), hemoglobin concentration, and arterial and venous oxygen saturations (SaO2 and SvO2, respectively) are known. Under normal circumstances, the quantities of oxygen demanded and oxygen consumed are equal, but in situations of inadequate oxygen delivery, oxygen demand may not be satisfied and the quantity of oxygen actually consumed will be governed by the quantity delivered. This then may result in an oxygen deficit and, ultimately, cellular death. This article discusses the principles of oxygen homeostasis, techniques for measuring VO2, CO, and SvO2, and the relevance of these principles and techniques to clinical practice.