Organ donation after circulatory death: current status and future potential.

The continuing shortage of deceased donor organs for transplantation, and the limited number of potential donors after brain death, has led to a resurgence of interest in donation after circulatory death (DCD). The processes of warm and cold ischemia threaten the viability of DCD organs, but these can be minimized by well-organized DCD pathways and new techniques of in situ organ preservation and ex situ resuscitation and repair post-explantation. Transplantation survival after DCD is comparable to donation after brain death despite higher rates of primary non-function and delayed graft function. Countries with successfully implemented DCD programs have achieved this primarily through the establishment of national ethical, professional and legal frameworks to address both public and professional concerns with all aspects of the DCD pathway. It is unlikely that expanding standard DCD programs will, in isolation, be sufficient to address the worldwide shortage of donor organs for transplantation. It is therefore likely that reliance on extended criteria donors will increase, with the attendant imperative to minimize ischemic injury to candidate organs. Normothermic regional perfusion and ex situ perfusion techniques allow enhanced preservation, assessment, resuscitation and/or repair of damaged organs as a way of improving overall organ quality and preventing the unnecessary discarding of DCD organs. This review will outline exemplar controlled and uncontrolled DCD pathways, highlighting practical and logistical considerations that minimize warm and cold ischemia times while addressing potential ethical concerns. Future perspectives will also be discussed.

Organ donation protocols.

Organ transplantation improves survival and quality of life in patients with end-organ failure. Waiting lists continue to grow across the world despite remarkable advances in the transplantation process, from the creation of public engagement campaigns to the development of critical pathways for the timely identification, referral, approach, and treatment of the potential organ donor. The pathophysiology of dying triggers systemic changes that are intimately related to organ viability. The intensive care management of the potential organ donor optimizes organ function and improves the donation yield, representing a significant step in reducing the mismatch between organ supply and demand. Different beliefs and cultures reflect diverse legislations and donation practices amongst different countries, creating a challenge to standardized practices. Maintaining public trust is necessary for continued progress in organ donation and transplantation, hence the urge for a joint effort in creating uniform protocols that ensure transparent practices within the medical community.

Maternal and neonatal outcomes in obese women who lose weight during pregnancy.

OBJECTIVE: To evaluate neonatal and maternal outcomes in obese pregnant women whose weight gain differed from the Institute of Medicine (IOM) recommendations. STUDY DESIGN: Maternal and neonatal outcomes associated with weight change in pregnancy were retrospectively investigated in women with obesity (body mass index (BMI) ⩾30 kg m(-2); N=10734) who gave birth at 12 hospitals. Using a 1:1:1:1 design (n=778 matched groups), we matched women with obesity who lost, maintained, gained appropriate (IOM recommended) and gained excessive weight during pregnancy by gestational age at delivery, maternal age, race/ethnicity, prepregnancy BMI, chronic hypertension, pregestational diabetes and smoking status. Regression techniques were used to adjust for confounders and compare outcomes across weight change categories. RESULT: Compared with IOM recommendations, weight loss was associated with twofold greater odds of low birth weight infants and a mean decrease in estimated blood loss of 30 ml; excessive weight gain was associated with doubled odds of gestational hypertension or preeclampsia, fourfold greater odds of macrosomia and a mean decrease in 5-min APGAR of 0.09. From lost to excessively gained weight, the odds of cesarean delivery increased 1.4 times and mean infant birth weight increased by 197 g. In contrast, the odds of small-for-gestational age were 1.8 times greater for women who lost than gained excessive weight. CONCLUSION: Weight loss in obese pregnant women is associated with increased risk for low birth weight neonates but significantly decreased or maintained risk for other maternal and neonatal morbidities, as compared with appropriate or excessive weight gain. This study supports re-evaluation of the current IOM guidelines for women with obesity.

Multi-Center Study of Diffusion-Weighted Imaging in Coma After Cardiac Arrest.

BACKGROUND: The ability to predict outcomes in acutely comatose cardiac arrest survivors is limited. Brain diffusion-weighted magnetic resonance imaging (DWI MRI) has been shown in initial studies to be a simple and effective prognostic tool. This study aimed to determine the predictive value of previously defined DWI MRI thresholds in a multi-center cohort. METHODS: DWI MRIs of comatose post-cardiac arrest patients were analyzed in this multi-center retrospective observational study. Poor outcome was defined as failure to regain consciousness within 14 days and/or death during the hospitalization. The apparent diffusion coefficient (ADC) value of each brain voxel was determined. ADC thresholds and brain volumes below each threshold were analyzed for their correlation with outcome. RESULTS: 125 patients were included in the analysis. 33 patients (26%) had a good outcome. An ADC value of less than 650 × 10(-6) mm(2)/s in ≥10% of brain volume was highly specific [91% (95% CI 75-98)] and had a good sensitivity [72% (95% CI 61-80)] for predicting poor outcome. This threshold remained an independent predictor of poor outcome in multivariable analysis (p = 0.002). An ADC value of less than 650 × 10(-6) mm(2)/s in >22% of brain volume was needed to achieve 100% specificity for poor outcome. CONCLUSIONS: In patients who remain comatose after cardiac arrest, quantitative DWI MRI findings correlate with early recovery of consciousness. A DWI MRI threshold of 650 × 10(-6) mm(2)/s in ≥10% of brain volume can differentiate patients with good versus poor outcome, though in this patient population the threshold was not 100% specific for poor outcome.

Functional contrast-enhanced CT for evaluation of acute ischemic stroke does not increase the risk of contrast-induced nephropathy.

BACKGROUND AND PURPOSE: Concerns have recently grown regarding the safety of iodinated contrast agents used for CTA and CTP imaging. We tested whether the incidence of AN, defined by a >or=25% increase in the post-contrast scan creatinine level, was higher among patients with ischemic stroke who underwent a functional contrast-enhanced CT protocol compared with those who had no iodinated contrast administration. MATERIALS AND METHODS: The contrast-exposed group consisted of 575 patients with acute ischemic stroke who underwent CTA (n = 313), CTA/CTP (n = 224), or CTA/CTP followed by conventional angiography (n = 38) within 24 hours of stroke onset and were consecutively enrolled in a prospective cohort study. The nonexposed group consisted of 343 patients with ischemic stroke, consecutively admitted to the same institution, who did not receive iodinated contrast material. Patients were stratified by baseline eGFR. In the primary analysis, the Fisher exact test was used to compare the incidence of AN between the contrast-exposed and the nonexposed patients at 24, 48, and 72 hours and on a cumulative basis. A secondary analysis compared the incidence of AN in patients who underwent conventional angiography following CTA/CTP versus patients who underwent CTA/CTP only. RESULTS: The incidence of AN was 5% in the exposed and 10% in the nonexposed group (P = .003). Patients who underwent conventional angiography after contrast CT were at no greater risk of AN than patients who underwent CTA/CTP alone (26 patients, 5%; and 2 patients, 5%, respectively; P = .7). CONCLUSIONS: Administration of a contrast-enhanced CT protocol involving CTA/CTP and conventional angiography in selected patients does not appear to increase the incidence of CIN.

Cerebral infarction in conjunction with patent foramen ovale and May-Thurner syndrome.

Stroke patients with paradoxical embolus mandate a search for deep venous thrombosis (DVT) in the lower extremities. Iliac vein compression, or May-Thumer syndrome, places certain patients at risk for development of DVT. The authors present 3 stroke patients with patient foramen ovale and paradoxical cerebral embolism, with demonstrated iliac vein compression as the presumed source of their embolus. May-Thumer syndrome should be considered a potential source of clot, as definitive therapy of this disorder can be curative.

Unilateral temporal lobe stroke causing ischemic transient global amnesia: role for diffusion-weighted imaging in the initial evaluation.

Ischemia has been proposed as a cause of transient global amnesia (TGA), but proof has been lacking. The authors performed magnetic resonance imaging on a 77-year-old woman with classic TGA at 4 hours and at 6 days after the onset of symptoms. Her initial diffusion-weighted imaging (DWI) and apparent diffusion coefficient imaging suggested an acute infarct in the left mesial temporal lobe. Follow-up T2-weighted imaging at 6 days confirmed the lesion as an ischemic infarct, despite resolution of her symptoms. DWI permits early detection of small ischemic lesions and may identify patients with ischemic TGA who should be evaluated for potential sources of emboli.

Biodistribution and radiation dosimetry of radioiodinated-SCH 23982, a potential dopamine D-1 receptor imaging agent.

Radioiodinated-SCH 23982 is a potential agent for the imaging of dopamine D-1 receptors in the human brain. In vivo binding of [125I]SCH 23982 to D-1 receptors in rat brain was determined over 4 hr. The ratio of activity in striatum and frontal cortex to that in cerebellum increased over the first 2 hr to maximum values of 4.4:1 and 2.1:1, respectively. The percent injected dose in whole brain at 0.5 and 2 hr were 0.62 and 0.15, respectively. Administration of the antagonists propranolol (beta-1), prazosin (alpha-1), haloperidol (D-2) and ketanserin (5HT-2) did not significantly alter the striatum/cerebellum ratio; however, SCH 23390, a D-1 antagonist, totally blocked ligand uptake by striatum and frontal cortex. Biologic distribution data in the rat were determined after injection of 3 microCi of [125I]SCH 23982. 76% of the injected dose was excreted in 48 hr via the liver and kidneys. Internal radiation absorbed dose estimates to nine source organs, total body, the GI tract, gonads and red bone marrow were calculated for humans using the physical decay data for 123I. The critical organ was found to be the lower large intestine which received 1.1 rad/mCi of the administered dose. The total-body dose was 63 mrad/mCi. The data indicate that [123I]SCH 23982 should be a suitable agent for imaging the D-1 dopamine receptor in the human brain by single photon emission computed tomography.

In vivo binding in rat brain and radiopharmaceutical preparation of radioiodinated HEAT, an alpha-1 adrenoceptor ligand.

In vivo binding of [125I]-2-[beta-(3-iodo-4-hydroxyphenyl)ethylaminomethyl tetralone) ([125I]HEAT) to alpha-1 adrenoceptors in the rat brain was determined over 4 hr. Uptake in the thalamus and frontal cortex was approximately 0.1% injected dose per gram tissue. Thalamus/cerebellum ratios of 10:1 and frontal cortex/cerebellum ratios of 5:1 were found at 4 hr. Pretreatment with prazosin, an alpha-1 antagonist, completely inhibited the accumulation of [125I]HEAT in thalamus and frontal cortex; yet uptake of radioactivity was not significantly affected by antagonists and agonists for other receptors classes (propranolol, beta-1; apomorphine, D-1; spiperone, D-2). Binding of [125I]HEAT is saturable. At 4 hr, [125I]HEAT or [123I]HEAT was shown to be the only radioactive material in rat thalamus and frontal cortex. Iodine-123 HEAT and [125I]HEAT were synthesized as radiopharmaceuticals within 3 hr in 99% radiochemical purity.

Radiation dosimetry of iodine-123 HEAT, an alpha-1 receptor imaging agent.

Biologic distribution data in the rat were obtained for the alpha-1 adrenoceptor imaging agent (+/-) 2-[beta-(iodo-4-hydroxyphenyl)ethylaminomethyl]tetralone (HEAT) labeled with [125I]. The major excretory routes were through the liver (67%) and the kidney (33%). Internal radiation absorbed dose estimates to nine source organs, total body, the GI tract, gonads, and red bone marrow were calculated for the human using the physical decay data for [123I]. The critical organ was found to be the lower large intestine, receiving 1.1 rad per mCi of [123I]HEAT administered. The total-body dose was found to be 58 mrad per mCi.

Excretion of octopamine metabolites in neuroblastoma.

The urinary concentrations of o-hydroxymandelic acid, m-hydroxymandelic acid, p-hydroxymandelic acid, homovanillic acid and vanillylmandelic acid were determined in 57 healthy children and 9 patients with neuroblastoma. The concentrations of o-hydroxymandelic acid and p-hydroxymandelic were not significantly different for both groups whereas the concentrations of m-hydroxymandelic acid, homovanillic acid and vanillylmandelic acid were elevated 20- to 30-fold in the neuroblastoma patients.

CINAHL list of subject headings: a nursing thesaurus revised.

The rationale and methods for revising the thesaurus of one of the major health sciences indexing tools are discussed. Computer production of the Cumulative Index to Nursing & Allied Health Literature and the possibility of online access mandated a revision of the list of subject headings. CINAHL has maintained a policy of responding to user needs and to changes in the nursing and allied health literature, and user input was encouraged during revision of the thesaurus. The methods of structural revision are described, and major changes in the thesaurus are detailed. Modification of the thesaurus is expected to have a far-reaching impact on the retrieval of information in nursing and allied health. Nursing and Allied Health (CINAHL) is now available online through DIALOG (file 218) and BRS (access code NAHL).

Congenital scalp defect with distal limb anomalies: brachydactyly and hypoplastic toes.

A case report of a congenital scalp defect with distal limb anomalies is presented. Etiology, associated anomalies, treatment, complications, and mortality are reviewed. The presence of prominent scalp veins may be an indication to defer rotation flaps and to obtain immediate coverage with a split-thickness skin graft after excision of the eschar.

Prepuce restoration seekers: psychiatric aspects.

A new subgroup of patients within the homosexual community has been identified who are characterized by preoccupation with their absent foreskins. They associate their circumcised status with a sense of incompleteness, anger over a lack of choice, and their sense of masculinity. Four patients who sought surgical reconstruction are reported. None were Jewish or psychotic. All tolerated surgery well. Preliminary etiologic hypotheses are advanced, emphasizing psychodynamic and imprinting possibilities.

"Acupuncture anesthesia"--a clinical study.

Forty-two patients who were to undergo plastic surgical procedures were asked whether they would accept acupuncture as a substitute for local anesthesia. Eight patients agreed to acupuncture; one of these had 2 operative procedures with acupuncture. Five of the 9 procedures were successful; the remaining 4 required conversion to local anesthesia. After interviewing the patients, we felt that the success of "acupuncture anesthesia" was largely dependent on patient motivation, and that a patient may experience pain during surgical procedures without any change in facial expression or vital signs. We concluded that "acupuncture anesthesia" is of little value in our patient population at present. Its results are unpredictable; therefore, we anticipate that patient acceptance will be small.