Stroke Volume Recruitability during the Third Trimester of Pregnancy.

OBJECTIVE: It is unknown whether the heart operates in the ascending or flat portion of the Starling curve during normal pregnancy. Pregnant women do not respond to the passive leg-raising maneuver secondary to mechanical obstruction of the inferior vena cava by the gravid uterus. Our objective was to evaluate if administration of a fluid bolus increases baseline stroke volume (SV) among healthy pregnant patients during the third trimester. STUDY DESIGN: Healthy pregnant women who underwent elective term cesarean sections were included. A noninvasive cardiac output monitor was used to measure hemodynamic variables at baseline and after administration of a 500-mL crystalloid bolus. RESULTS: Forty-five women were included in the study. Fluid administration was associated with a statistically significant increase in SV from a baseline value of 71 ± 11 to 90 ± 19 mL (95% confidence interval [CI]: 13.67-21.49; p < 0.01) and a significant decrease in maternal heart rate from a baseline of 87 ± 9 beats per minute to 83 ± 8 after the fluid bolus (95% CI: -6.81 to -2.78; p = 0.03). No changes in peripheral vascular resistances or any other measured hemodynamic parameters were noted with volume expansion. CONCLUSION: In healthy term pregnancy, the heart operates in the ascending portion of the Starling's curve, rendering it fluid responsive.

Carbon Monoxide and Cyanide Poisoning in the Burned Pregnant Patient: An Indication for Hyperbaric Oxygen Therapy.

Carbon monoxide (CO) is a small molecule poison released as a product of incomplete combustion. Carbon monoxide binds hemoglobin, reducing oxygen delivery. This effect is exacerbated in the burned pregnant patient by fetal hemoglobin that binds CO 2.5- to 3-fold stronger than maternal hemoglobin. With no signature clinical symptom, diagnosis depends on patient injury history, elevated carboxyhemoglobin levels, and alterations in mental status. The standard of care for treatment of CO intoxication is 100% normobaric oxygen, which decreases the half-life of CO in the bloodstream from 5 hours to 1 hour. Hyperbaric oxygen (HBO2) is a useful adjunct to rapidly reduce the half-life of CO to 20 minutes and the incidence of delayed neurologic sequelae. Because of the slow disassociation of CO from hemoglobin in the fetus, there is a far stronger indication for HBO2 in the burned pregnant patient than in other burn patient populations.Cyanide intoxication is often a comorbid disease with CO in inhalation injury from an enclosed fire, but may be the predominant toxin. It acts synergistically with CO to effectively lower the lethal doses of both cyanide and CO. Diagnosis is best made in the presence of high lactate levels, carboxyhemoglobin concentrations greater than 10%, injury history of smoke inhalation from an enclosed fire, and alterations in consciousness. While treatment with hydroxocobalamin is the standard of care and has the effect of reducing concomitant CO toxicity, data indicate cyanide may also be displaced by HBO2.Carbon monoxide and cyanide poisoning presents potential complications impacting care. This review addresses the mechanism of action, presentation, diagnosis, and treatment of CO and cyanide poisonings in the burned pregnant patient and the use of HBO2 therapy.

Enmeshed in Controversy: Use of Vaginal Mesh in the Current Medicolegal Environment.

UNLABELLED: Vaginal mesh has been a valuable tool in the treatment of stress urinary incontinence and pelvic organ prolapse. As our knowledge of the long-term outcomes and complications of this product has evolved, however, vaginal mesh has become the subject of legal scrutiny. Therefore, it is imperative that physicians understand pertinent litigation techniques to optimize their informed consent and documentation processes and protect themselves. OBJECTIVES: Our objective is to familiarize physicians who use vaginal mesh with how law suits involving transvaginal mesh are construed. We also describe the current medicolegal environment surrounding the use of these products. METHODS: The food and drug administration public safety communications, food and drug administration Manufacturer and User Facility Device Experience database, and LexisNexis legal search engine were used to review data relevant to current vaginal mesh litigation. This information was used to create a medicolegal review. RESULTS: Litigation involving transvaginal mesh follows 3 paths. The first consists of claims against the manufacture of transvaginal mesh with allegations, such as design defects, failure to warn, and misrepresentation. The second is a defensive legal strategy called the learned intermediary doctrine, used by manufacturers to shift liability from themselves to surgeons. The manufacturers claim that the duty to inform patients of potential complications lies with the surgeon. The third involves claims by patients against surgeons for lack of informed consent, alleging that they were not sufficiently informed of potential complications associated with transvaginal mesh before insertion. CONCLUSIONS: To lessen the liability, a surgeon using transvaginal mesh should inform patients of potential complications associated with the products and document informed consent in their medical records.