摘要:

CommentThis investigation, which concluded that intravenous midazolam, 75 μg/kg, reduced vomiting after tonsillectomy in children, had a number of strong design features, including large (more than 100 patients) sample sizes, a power level of 0.80, and precise application of the nonparametric Fisher's exact test to assess differences between the placebo-and midazolam-treated groups in unscheduled hospital admissions for vomiting. This investigation also had a number of design weaknesses, including investigator bias, confounding by the administration of anesthetics and analgesics with emetic effects, and underrepresentation of males in both study samples.Investigator bias was introduced in the topic sentence that “hypothesized that midazolam would decrease vomiting after tonsillectomy in children.” Investigators should have remained neutral, unbiased observers, prepared to test the null hypothesis of no effect (midazolam equals placebo) with appropriate test statistics.Fentanyl, nitrous oxide, and neostigmine were administered intraoperatively to all patients and have been associated with postoperative vomiting (POV). Although both placebo and midazolam-treated groups received the same anesthetics, confounding between anesthetic adjuvants and POV could have been eliminated by avoiding known emetics and by administering air/oxygen, nonnarcotics, and short-acting muscle relaxants that do not require reversal. The postoperative administration of codeine, another emetic, may have also confounded assessment of POV in the treatment groups.The authors correctly emphasized that POV is age-related and that their study groups were similar for age, eliminating confounding by age. Unfortunately, POV is also sex-related, more common in adolescent females than males, especially at menarche and during menses. There were more females than males in both groups (placebo, 52% female; midazolam, 53% female) again confounding proper assessment of pure treatment effects, not sex-related effects, on POV.Finally, the study groups were separate and distinct (unpaired) and were assessed for effects and outcome differences appropriately with the unpairedt-test. Where was the pairedt-test (to assess differences in the same group) applied? A possible application would have been to evaluate hospital admission rates for vomiting in each group separately, with each group serving as its own control, but this was not reported.

ISSN:0039-6206    

出版商:OVID    

年代:1996

数据来源: OVID

ISSN:0039-6206    

出版商:OVID    

年代:1996

数据来源: OVID

ISSN:0039-6206    

出版商:OVID    

年代:1996

数据来源: OVID

ISSN:0039-6206    

出版商:OVID    

年代:1996

数据来源: OVID

ISSN:0039-6206    

出版商:OVID    

年代:1996

数据来源: OVID

ISSN:0039-6206    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

CommentIn this report of an anaphylactic response to readministration of aprotinin, the audiors caution that many institutions may have overestimated the benefits of aprotinin administration relative to its risks. Therefore, it is important to define appropriate criteria to limit aprotinin exposure. It is also important to be certain that aprotinin is properly administered. The manufacturer's package insert recommends that a 1-cc (10,000 KIU) dose be given 10 min before administering the loading infusion. Furthermore, it is recommended that the loading dose be given for 20 to 30 min. Hence, the rate of administration in this case report seems to have

ISSN:0039-6206    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

CommentThe stated purpose of this article was to find the optimal dose of tranexamic acid using a methodology of bolus administration followed by infusion of one-tenth that bolus for 12 hr. The reader is reminded that this study only looked at postoperative blood loss and not intraoperative blood loss. Although this paper is well presented, its real interest perhaps stems from issues relating to blood conservation that were alluded to in the text.The first was the attempt to identify factors that were linked to less postoperative blood loss. These were female gender, undergoing repeat sternotomy, and increased weight. The reduced blood loss found in patients having repeat sternotomy is, of course, counterintuitive. Although the authors introduce the possibility that tranexamic acid may have some increased efficacy in patients undergoing repeat sternotomy, the more likely explanation lies in the fact that only 20 (13%) of their patients were having repeat cardiac surgery. They also point out that the surgical team may have been more attentive to intraoperative hemostasis in this category of patients.Although tranexamic acid reduced total postoperative blood loss, the only risk factor for receiving a blood transfusion was having a low hematocrit initially. Tranexamic acid approached significance (P< 0.075) and might have an impact on a population larger than 200. Another explanation may be that this team was willing to withhold transfusions until the hematocrit was 20%, thereby reducing the overall incidence of transfusions and placing only a select group of patients at risk in the first place.

ISSN:0039-6206    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

CommentThe press continues to report harrowing stories concerning the costs of providing intensive care. The adage “thou shalt not kill; but need'st not strive officiously to keep alive‘” has helped countless doctors to come to terms with the problem of how hard they should try. The prospect of the quality of life in the event of survival is also an important consideration. I can look back on a number of occasions in which my sheer doggedness led to a good survival. This paper is a valuable study, and the authors are quick to point out that the financial and legal atmosphere in Canada may vary from other parts of the world. The authors quote studies that show that not all physicians are as comfortable as some ethicists would have us believe (i.e., that there is no difference between withdrawing life support and not initiating it), and some feel that, although it may be appropriate to withhold treatment, it is not right to withdraw it.

ISSN:0039-6206    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

CommentThere has been recent awareness that carbon monoxide (CO) and hydrogen cyanide are synergistic in preventing the use of oxygen by tissues. Hydrogen cyanide is the most lethal of several poisonous gases generated in fires, especially those involving foam-filled furniture such as polyurethane and polyacrylonitrile. Outside of the emergency trauma admitting room, most anesthesiologists' knowledge about cyanide poisoning stems from the use of sodium nitroprusside as a hypotensive agent where cyanide may be released.The message of this paper is “think cyanide poisoning” as well as CO toxicity when patients are rescued from fires and maintain mechanical ventilation of the lungs with oxygen. Specific cyanide antidotes may be unnecessary or should be given with great care. Serial blood samples are needed for cyanide analysis, which is a difficult assay. The efficacy of the treatment of cyanide poisoning as a result of fires needs to be rethought frequently lest the therapy prove a danger in itself.

ISSN:0039-6206    

出版商:OVID    

年代:1996

数据来源: OVID