Peripartum anesthetic management in patients with left ventricular noncompaction: a case series and review of the literature.

BACKGROUND: This retrospective review focuses on peripartum anesthetic management and outcome of a series of five pregnant women with left ventricular noncompaction (LVNC). METHODS: The Mayo Clinic Advanced Cohort Explorer medical database was utilized to identify women diagnosed with LVNC who had been admitted for delivery at the Mayo Clinic in Rochester, Minnesota, between January 2001 and September 2021. Echocardiograms were independently reviewed by two board-certified echocardiographers, and those determined by both to meet the Jenni criteria and/or having compatible findings on magnetic resonance imaging (MRI) were included. Electronic medical records were reviewed for information pertaining to cardiac function, labor, delivery, and postpartum management. RESULTS: We identified 44 patients whose medical record included the term "noncompaction" or "hypertrabeculation" and who had delivered at our institution during the study period. Upon detailed review of the medical records, 36 did not meet criteria for LVNC, and three additional patients did not receive the diagnosis until after delivery, leaving five patients with confirmed LVNC who had undergone six deliveries during the study interval. All five patients had a history of arrhythmias or had developed arrhythmias during pregnancy. One patient underwent emergency cesarean delivery due to sustained ventricular tachycardia requiring three intra-operative cardioversions. CONCLUSIONS: This case series adds new evidence to that already available about pregnancies among women with LVNC. Favorable obstetrical outcomes were achievable when multidisciplinary teams were prepared to manage the maternal and fetal consequences of intrapartum cardiac arrhythmias and hemodynamic instability.

Urgent cesarean delivery and prolonged ventilatory support in a parturient with Fontan circulation and undiagnosed pseudocholinesterase deficiency.

A parturient with Fontan circulation required general anesthesia for urgent cesarean delivery and subsequent prolonged postoperative ventilation for newly-diagnosed pseudocholinesterase deficiency. Anesthetic management necessitated a thorough understanding of the hemodynamic principles of the Fontan circulation and physiologic adaptations during surgical delivery and recovery in the intensive care unit.

In-utero stenting: development of a low-cost high-fidelity task trainer.

OBJECTIVE: To develop an in-utero stent placement training model. METHODS: The in-utero stent task trainer was constructed using a formalin-preserved gravid pig uterus. Altering the size of the uterine segment, changing the fluid level in the uterus and addition of a large Ziploc freezer bag variably filled with differing amounts of ultrasound gel can vary the procedural skill required. RESULTS: Thoracoamniotic and vesicoamniotic shunts can be simulated using this life-like model. The cost of eight to 10 learning stations is approximately US $ 60. Fetal position, maternal size and amniotic fluid status can be altered rapidly to increase the complexity of the procedure. CONCLUSIONS: This low-cost and realistic task trainer can provide the opportunity to practice in-utero shunt procedures in a non-clinical environment. This model should enhance learning and reinforce acquired skills.

Abacavir pharmacokinetics during chronic therapy in HIV-1-infected adolescents and young adults.

The pharmacokinetics of abacavir and its metabolites were investigated in 30 human immunodeficiency virus (HIV)-infected adolescents and young adults 13-25 years of age, equally divided into two groups: <18 years of age and >or=18 years of age. All the subjects received the recommended adult dose of 300 mg twice daily. The area under the plasma concentration-time curve (AUC) and half-life of abacavir did not differ significantly between the age groups or by gender or race, and there were only modest associations of age with apparent abacavir clearance and with volume of distribution. There were no significant correlations of carboxylate or glucuronide metabolite levels with age or gender, although glucuronide AUC was higher in Hispanic subjects than in African-American subjects. Zidovudine and lamivudine concentration profiles were also similar in the two age groups. A novel aspect of the study included an assessment of intracellular carbovir, zidovudine, and lamivudine triphosphate levels, and these were found to be similar in the two age-based groups. Overall, these findings suggest that current recommendations relating to adult dosages are appropriate for adolescents and young adults.

Successful term pregnancy following MR-guided focused ultrasound treatment of uterine leiomyoma.

OBJECTIVE: Term vaginal delivery after magnetic resonance-guided focused ultrasound therapy (MRgFU) for symptomatic uterine leiomyoma. STUDY DESIGN: A 38-year-old nulligravida underwent MRgFU treatment per study protocol for a solitary 9 x 10 x 10 cm uterine myoma and conceived 18 months following the procedure. She was counseled on the unknown implications of MRgFU during subsequent pregnancy. Myoma size increased significantly during gestation. At 39 weeks, she underwent indicated labor induction with vacuum-assisted vaginal delivery of a healthy male infant. CONCLUSION: In one pregnancy following MRgFU, there were no associated antepartum or intrapartum obstetrical complications.

Uterine prolapse associated with bladder exstrophy: surgical management and subsequent pregnancy.

Congenital bladder exstrophy affects 1 in 125,000 to 250,000 females. Consisting of absence of the anterior abdominal wall with exposure of the ureteral orifices, failure of pubic symphysis fusion, and deficient anterior pelvic diaphragm musculature, bladder exstrophy is frequently associated with genital prolapse. Pregnancy may be complicated by recurrent urinary tract infections, preterm labor, mild procidentia, and malpresentation. Due to the rarity of the condition, there is a corresponding scarcity of obstetric literature regarding management during pregnancy. We report the case of a young woman with surgically repaired bladder exstrophy who developed genital prolapse. The uterus was suspended using a sacral colpopexy utilizing a Gore-Tex graft. Subsequently, the patient became pregnant and delivered a healthy male infant at 35 weeks' gestation via cesarean section (without recurrence of the genital prolapse postpartum). Sacral colpopexy to correct genital prolapse associated with bladder exstrophy may preserve fertility in young patients.

Occurrence and magnitude of pressure waves during Er:YAG laser ablation of atherosclerotic tissue: comparison to XeCl excimer laser ablation.

BACKGROUND AND OBJECTIVE: Since excimer laser ablation has not shown advantages in comparison to conventional balloon angioplasty, the search for other laser light sources came up with the Er:YAG laser, operating at a wavelength of 2.94 microns. STUDY DESIGN/MATERIALS AND METHODS: Normal and atherosclerotic human vessel segments were irradiated in vitro, using pulsed Er:YAG laser systems. The laser beam was either focused onto the tissue in air or delivered via a fibre system onto the tissue being immersed in saline. Needle-type hydrophones were used for pressure pulse detection. RESULTS: Er:YAG laser irradiation results in effective tissue ablation of normal and calcified atherosclerotic vessel segments. In comparison to excimer lasers, ablation rates can be increased by a factor of 5 to 10 at least. Er:YAG laser ablation is also associated with a generation of pressure waves. On calcified plaque, the acoustic signals differ significantly from those on normal tissue. Histological tissue analysis reveals small zones of discoloration and tissue fissures that are found 100-200 microns lateral to the crater edge, depending on the energy density used. CONCLUSION: Er:YAG lasers generate pressure waves that are comparable to excimer laser ablation. Er:YAG lasers, however, show a markedly improved ablation efficiency, which may favour these systems as effectively cutting, less traumatic tools for removal of atherosclerotic plaque.

Comparing a high-dose dipyridamole SPECT imaging protocol with dobutamine and exercise stress testing protocols.

OBJECTIVE: To determine the safety, sensitivity, specificity, and accuracy of high-dose dipyridamole compared with treadmill and dobutamine stress imaging protocols. BACKGROUND: Nuclear imaging studies using standard dose dipyridamole provide similar results to those obtained when treadmill stress is used. Recently dobutamine tomography and planar imaging with high-dose dipyridamole have been shown no improve nuclear imaging results. METHODS: One hundred fifty-nine patients were imaged with thallium, teboroxime, or sestamibi per standard single photon emission computed tomography (SPECT) protocols. Pharmacologic stress was performed in 85 people with the remainder undergoing exercise testing by Bruce protocol. In this study, 0.852 mg dipyridamole was used per kilogram body weight and was infused over a four-minute period. Results from nuclear imaging were compared with those from coronary arteriograms. RESULTS: The sensitivity and specificity of high-dose dipyridamole was 100% and 88.9%, respectively, which is statistically greater (P < 0.005) than that achieved when patients were stressed by treadmill. Side effects with the higher dose of dipyridamole were easily reversed with aminophylline. The sensitivity and specificity of intravenous dobutamine was 100%, but it was used in a limited number of subjects. When patients were stressed by Bruce protocol the sensitivity was 92.5% and specificity was 42.8%. The differences were not attributable to inadequate exercise duration. CONCLUSIONS: High-dose dipyridamole is safe and easily reversed with intravenous aminophylline. The sensitivity and specificity of dipyridamole and dobutamine stress testing were statistically more accurate than results obtained with treadmill protocols when SPECT is used to image the heart. High-dose dipyridamole resulted in greater changes in heart rate and blood pressure response than seen with standard-dose dipyridamole. Associated side effects can be easily reversed with the administration of intravenous aminophylline without significant complications. The sensitivity, specificity, and accuracy of single photon emission computed tomography using high-dose dipyridamole are 100%, 88.9%, and 97.9%, respectively, for the overall presence or absence of disease when compared with coronary arteriography. This is significantly (P < 0.005) greater than that obtained by treadmill nuclear imaging protocols, independent imaging agent.

Epidemiology of Nematodirus species infections of sheep in a subarctic climate: development and persistence of larvae on herbage.

As part of a study on the epidemiology of Nematodirus species of sheep in subarctic Greenland, the development and persistence of eggs and larvae were investigated by experimentally contaminating plots of pasture with infected faeces and by placing tubes containing a suspension of eggs on to or into the soil. Despite low ambient temperatures, infective larvae appeared within a month during the summer. The greatest numbers of larvae were recovered from herbage in August and September. Eggs did not develop synchronously as development beyond the morula stage could be delayed for up to two years. Larvae were found on herbage for up to 37 months after faecal deposition. In the sheep rearing area of Greenland, therefore, Nematodirus species larvae can be present on herbage throughout the whole summer but peak numbers occur late in the grazing season.

Studies on Ostertagia spp. from Greenlandic sheep: arrested development and worm length.

Studies were conducted to investigate earlier observations that lambs slaughtered in Greenland in late September/early October have relatively few arrested larvae in the abomasal mucosa and that the adult Ostertagia from such lambs are abnormally large. Post mortem examination of naturally infected ewes in mid-winter demonstrated that a significant proportion of their Ostertagia population was hypobiotic at this time of year, while an experimental study showed that considerable numbers of larvae of Greenlandic origin became arrested following cold conditioning for 10 weeks. A comparison of adult Ostertagia of Greenlandic and Britain origins from lambs experimentally infected with larvae cultured under identical conditions demonstrated that the "giant" size of the arctic worms was attributed mainly to environmental rather than genetic influences.

Epidemiology of sheep nematodes in sub-arctic Greenland: sources of infection on rangeland grazing.

Sources of nematode infection on the rangelands of a southern Greenlandic sheep farm were investigated as a part of a study of the epidemiology of Ostertagia and Nematodirus infections in a sub-arctic climate. Herbage larval counts were performed on samples collected from selected localities on the rangeland and post mortem worm-counts made on tracer lambs that had grazed these areas for the latter part of the summer season. Relatively high concentrations of larvae were found in good quality native grasses at sea-level and in grasses growing beneath canopies of willow-shrub at higher altitudes. In general, however, the infectivity of the vegetation was very low and the pick-up of infection by the tracer lambs was correspondingly small.

Sheep farming in Greenland. Its history, managemental practices and disease problems.

The economy of the Greenlandic sheep industry has always operated on a thin edge, the balance being determined by long-term changes in climate and year-to-year weather fluctuations. During the last decades sheep farming has been intensified in many areas, and more rational management systems have been introduced under the guidance of agricultural and veterinary consultants. Improvements include winter feeding, strategic breeding and lambing practices and disease control programmes. Successful efforts are being made to prevent the recurrence of previous dramatic declines in the sheep population and to diminish losses of growing lambs grazing the extensive rangelands. However, the overall disease situation and the effect of environmental stresses on the breeding stock and growing lambs in this unique, subarctic region are far from being fully explored.

Studies on the helminth parasites of sheep in Southern Greenland.

The nematode population of sheep on Greenland is dominated by Ostertagia circumcincta and three Nematodirus species: N. spathiger, N. helvetianus and N. abnormalis. These results are compared with those for other Nordic countries. Great similarities exist with subarctic Norway but there is a lesser degree of correlation with Iceland and lowland Norway which tend to have a richer spectrum of species. N. helvetianus and N. abnormalis, however, have not been reported from sheep in these countries. The abomasal worm population was remarkable in that it contained specimens with an abomally large body size. The epidemiology of infection followed the pattern recognized throughout Europe with an early-season periparturient rise in the faecal egg-count of the ewe being followed by increasing levels of infection in lambs in late summer. The epidemiology of Nematodirus infections was quite distinct from that seen in most of Europe. Species differences and the cool summer climate were thought to account for this disparity and a hypothesis was advanced to explain the observed pattern of events. Levels of infection were apparently similar in undergrazed and fully-utilized grazing areas. Dosing ewes during the winter (between November to March) eliminated the periparturient egg rise. Lambs could be kept almost worm free by keeping them on clean rangeland and dosing at 3-5 week intervals. A clear weight-gain advantage over conventionally reared lambs was only recorded in one year of the study.