Biomedical subjects

J Nanson

Publications and source records attributed to J Nanson.

11 recordsLinked to original sources

PubMed2002

A prospective randomized study to evaluate the renoprotective action of beating heart coronary surgery in low risk patients.

OBJECTIVES: Cardiopulmonary bypass (CPB) is widely regarded as an important contributor to renal failure, a well recognized complication following coronary artery surgery (coronary artery bypass grafting (CABG)). Anecdotally off-pump coronary surgery (OPCAB) is considered renoprotective. We examine the extent of renal glomerular and tubular injury in low-risk patients undergoing either OPCAB or on-pump coronary artery bypass (ONCAB). METHODS: Forty low-risk patients with normal preoperative cardiac and renal functions awaiting elective CABG were prospectively randomized into those undergoing OPCAB (n=20) and ONCAB (n=20). Glomerular and tubular injury were measured respectively by urinary excretion of microalbumin and retinol binding protein (RBP) indexed to creatinine (Cr). Daily measurements were taken from admission to postoperative day 5. Fluid balance, serum Cr and blood urea were also monitored. RESULTS: No mortality or renal complication were observed. Both groups had similar demographic makeup, Parsonnet score, functional status and extent of coronary revascularization (2.1+/-1.0 vs. 2.5+/-0.7 grafts; P=0.08). Serum Cr and blood urea remained normal in both groups throughout the study. A significant and similar rise in urinary RBP:Cr occurred in both groups peaking on day 1 (3183+/-2534 vs. 4035+/-4079; P=0.43) before reapproximating baseline levels. These trends were also observed with urinary microalbumin:Cr (5.05+/-2.66 vs. 6.77+/-5.76; P=0.22). Group B patients had a significantly more negative fluid balance on postoperative day 2 (-183+/-1118 vs. 637+/-847 ml; P=0.03). CONCLUSIONS: Although renal complication or serum markers of kidney dysfunction were absent, sensitive indicators revealed significant and similar injury to renal tubules and glomeruli following either OPCAB or ONCAB. These results suggest that avoidance of CPB does not offer additional renoprotection to patients at low risk of perioperative renal insult during CABG.

Aged↗

PubMed2001

Do physiological changes in pregnancy change defibrillation energy requirements?

Resuscitation during pregnancy is uncommon, with approximately 70 deaths occurring during pregnancy in the UK per annum. Physiological changes during pregnancy may affect transthoracic impedance (TTI), which determines transmyocardial current. Increased blood volume, cardiomegaly, haemodilution, changes in lung volume and changes in thoracic volume may alter impedance in ways that are difficult to predict. We measured TTI at term and after delivery once physiological changes had resolved. Mean (SD) TTI was 91.3 (15.8) Omega at term and 91.6 (11.8) Omega 6-8 weeks after delivery; the difference was not statistically significant. We conclude that current energy requirements for adult defibrillation are appropriate for use during pregnancy.

Adult↗

PubMed2001

Primary pulmonary hypertension in pregnancy; a role for novel vasodilators.

We describe the case of a 28-week pregnant woman presenting with severe primary pulmonary hypertension (PPH). She had an elective Caesarean section under general anaesthesia at 32 weeks gestation. Pulmonary artery pressures (PAP) measured from a pulmonary artery catheter before anaesthesia were in excess of 100 mm Hg. Intraoperative nitric oxide was used to reduce PAP. After the delivery of a healthy infant PAP was controlled with nebulized iloprost and a prostacyclin infusion. Seven days later she was discharged from intensive care taking an oral calcium antagonist and warfarin. She developed intractable right heart failure and died 14 days after delivery. Despite increasing experience in the use of drugs to reduce PAP, the clinical course of pregnancy complicated by severe PPH is usually fatal.

Adult↗

PubMed2000

Outcome at age 4 years in offspring of women with maternal phenylketonuria: the Maternal PKU Collaborative Study.

CONTEXT: Untreated maternal phenylketonuria (PKU) increases risk for developmental problems in offspring. The extent to which this risk is reduced by maternal dietary therapy at various stages of pregnancy is not known. OBJECTIVE: To determine whether dietary treatment during pregnancy of women with PKU affects developmental outcomes of offspring. DESIGN: The Maternal PKU Collaborative Study, an ongoing, longitudinal prospective study begun in 1984. SETTING: A total of 78 metabolic clinics and obstetrical offices in the United States, Canada, and Germany. PARTICIPANTS: A total of 253 children of women with PKU (n = 149), with untreated mild hyperphenylalaninemia (n = 33), or without known metabolic problems (comparison group; n = 71) were followed up to age 4 years. INTERVENTION: Women with PKU were offered a low-phenylalanine diet prior to or during pregnancy with the aim of maintaining metabolic control (plasma phenylalanine < or =10 mg/dL [< or =605 micromol/L]). Women with mild hyperphenylalaninemia, who had plasma phenylalanine levels of no more than 10 mg/dL (605 micromol/L) on a normal diet, were not treated. MAIN OUTCOME MEASURES: Children's scores on cognitive and behavioral assessments (McCarthy Scales of Children's Abilities, Test of Language Development, Achenbach Child Behavior Checklist, Vineland Adaptive Behavior Scales, and Home Observation for Measurement of the Environment), compared by maternal metabolic status at 0 to 10 weeks', 10 to 20 weeks', and after 20 weeks' gestation. RESULTS: Scores on the McCarthy General Cognitive Index decreased as weeks to metabolic control increased (r = -0.58; P<.001). Offspring of women who had metabolic control prior to pregnancy had a mean (SD) score of 99 (13). Forty-seven percent of offspring whose mothers did not have metabolic control by 20 weeks' gestation had a General Cognitive Index score 2 SDs below the norm. Overall, 30% of children born to mothers with PKU had social and behavioral problems. CONCLUSIONS: Our data suggest that delayed development in offspring of women with PKU is associated with lack of maternal metabolic control prior to or early in pregnancy. Treatment at any time during pregnancy may reduce the severity of delay.

Child Behavior↗

PubMed2000

Education and debriefing: strategies for preventing crises in crisis-line volunteers.

Telephone crisis lines offer an important service to individuals in crisis. The accessibility as well as a lack of other means of support leads many individuals to call the line. The role of the volunteer is to listen and support the caller as well as provide information and referrals to other agencies. Agencies are presented with a high turnover of volunteers and are then faced with the task of recruiting and training replacements. Volunteers are often exposed to horrific accounts of human pain and suffering which may affect their personal thoughts, feelings, beliefs and actions and influence the decision to quit. Compassion fatigue is one term used for this inherent "cost of caring." Many factors contribute to this cost including the nature of crisis calls, the repeat caller, and personal coping mechanisms. Educating and debriefing the volunteer are two strategies that may prevent the onset of compassion fatigue and volunteer resignation. Debriefing is viewed as an effective strategy for volunteers as it has been found to be successfull in assisting other helpers in many different contexts to cope and deal with the traumatic events that they experience or hear about.

Burnout, Professional↗

PubMed2000