Search is a time-critical event: when search and rescue missions may become futile.

OBJECTIVES: The purpose of this study was to derive and validate a rule for duration of search (ie, search time) that maximizes survivors and after which a search and rescue (SAR) mission may be considered for termination. METHODS: This was a retrospective cohort study of all SAR missions initiated in Oregon over a 7-year period, which were documented in a population-based administrative database. The following types of search missions were excluded from analysis: redundant reports of a single search; lost helicopters and airplanes; support of organized events; law-enforcement searches; searches for persons actively avoiding rescue; body recovery missions; and cases without outcome information. The cohort was divided into a derivation cohort (searches from 1997-2000) and a validation cohort (2001-2003). The primary outcome was survival. Variables considered in the model included age, gender, minimum and maximum daily temperatures, precipitation, search time, and whether the search involved an air or water incident. Missing data were handled using multiple imputation. Classification and regression tree (CART) methods were used to derive the model. RESULTS: The derivation cohort included 1040 searches involving 1509 victims, 70 (4.6%) of whom died. The validation cohort included 1262 searches involving 1778 victims; 115 (6.5%) died. Search time was the only variable retained in the final model, with a cut-point of 51 hours. The derivation model was 98.9% sensitive; the same model run using the validation cohort was 99.3% sensitive. CONCLUSIONS: This time-based model may aid search managers in the decision about starting a search or changing search tactics for missing persons.

Paroxysmal atrial fibrillation precipitated by amiodarone-induced thyrotoxicosis five months after cessation of therapy.

Amiodarone is currently indicated for the treatment of life-threatening ventricular dysrhythmias. It is also used for the treatment of supraventricular dysrhythmias and as maintenance therapy after successful cardioversion of atrial flutter or atrial fibrillation. Adverse effects related to its expanded use are increasingly common. We describe a case of amiodarone-induced thyrotoxicosis occurring 5 months after cessation of therapy and discuss the pathophysiology and treatment of this disorder.

Perimortem cesarean delivery: were our assumptions correct?

OBJECTIVE: The recommendation to perform a perimortem cesarean delivery within 4 minutes of maternal cardiac arrest was introduced in 1986. This recommendation was based on the assumptions that cardiopulmonary resuscitation is ineffective in the third trimester because of aortocaval compression, and that fetal and perhaps maternal outcomes would be optimized by timely delivery. Our objective was to review the outcomes of perimortem cesarean deliveries to attempt to validate those assumptions. STUDY DESIGN: Ovid MEDLINE searches using maternal mortality, cardiopulmonary resuscitation, perimortem cesarean delivery, heart attack, and cardiac arrest from 1985 until 2004. Citations from bibliographies of identified publications were perused and cross-referenced for other potential articles. Case reports were included for analysis when mothers had complete cardiopulmonary arrest, and cardiopulmonary resuscitation had been initiated before cesarean delivery. RESULTS: There were 38 cases of perimortem cesarean delivery identified; 34 infants survived (3 sets of twins, 1 set of triplets); 4 other infants survived initially, but died several days after the deliveries from complications of prematurity and anoxia. Of the 34 infants (25-42 weeks' gestation), time of delivery after maternal cardiac arrest was available for 25. Eleven infants were delivered within 5 minutes, 4 were delivered from 6 to 10 minutes, 2 were delivered from 11 to 15 minutes, and 7 were delivered more than 15 minutes. Of 20 perimortem cesarean deliveries with potentially resuscitatable causes, 13 mothers were resuscitated and discharged from the hospital in good condition. One other mother was successfully resuscitated after the delivery, but died within 24 hours from complications related to her amniotic fluid embolism. In 12 of 18 reports that documented hemodynamic status, cesarean delivery preceded return of maternal pulse and blood pressure, often in a dramatic fashion. Eight other cases noted improvement in maternal status. Importantly, in no case was there deterioration of the maternal condition with the cesarean delivery. We wish to emphasize the large selection bias in this data. CONCLUSION: Published reports from 20 years support, but fall far from proving, that perimortem cesarean delivery within 4 minutes of maternal cardiac arrest improves maternal and neonatal outcomes.