Intracardiac surgery in infants under age 3 months: Incremental risk factors for hospital mortality

During the 13 year period from January 1967 to July 1980, the hospital mortality rate for open intracardiac operations in infants in the first 3 months of life was 43 percent (75 deaths among 194 patients), higher than the 22 percent mortality rate (35 deaths in 161 patients) for closed operations in the same age group. The mortality rate was lower late in the experience (p = 0.0001). Poor preoperative condition of the patient increased the mortality rate 87 percent in patients preoperatively acidotic or in shock [preoperative class V]and 22 percent in patients with moderate or severe symptoms but without recent hemodynamic deterioration (preoperative class II or III). The presence of major associated cardiac lesions increased hospital mortality (p < 0.0001). The hospital mortality rate was highest (59 per cent) in infants less than age 1 month, possibly in part because of their sensitivity to the damaging effects of cardiopulmonary bypass. This hypothesis is supported by the association of a long period of cardiopulmonary bypass with increased hospital mortality (p = 0.05) and of total circulatory arrest during profound hypothermia with decreased mortality (p = 0.05). Most deaths (72 percent) occurred in association with acute postoperative cardiac failure. The length of cardiac ischemia (aortic cross-clamping time) was directly related to the probability of cardiac death, unless cold cardioplegia was used. Thirteen percent of the hospital deaths were associated with acute postoperative respiratory failure. Current mortality rates in typical cases without acute hemodynamic deterioration is estimated from these data to be 7 percent (70 percent confidence limits 4 to 12 percent), as a result of the scientific advances made over this period of time. Research into mechanisms of the damaging effects of cardiopulmonary bypass should further improve results in these very young patients.     

Infection and rejection risk after cardiac transplantation with induction vs. no induction: a multi‐institutional study

Data from Cardiac Transplant Research Database (CTRD) were analyzed from 1999 to 2006 to examine the effects of different induction strategies at the time of cardiac transplantation. A total of 2090 primary heart transplants were categorized by induction with interleukin‐2 receptor blocker (IL‐2RB), antithymocyte globulin (ATG), or no induction (NI). Probabilities for rejection and infection were estimated with parametric time‐related models. Using these models, hazard was calculated for two theoretical patient profiles, one at lower risk for rejection and higher risk of infection (Profile 1) and higher risk for rejection and lower risk of infection (Profile 2). Of the 2090 transplants, 49.8% (1095) did not receive induction, 27.3% (599) received IL‐2RB, and 18.0% (396) received ATG. Profile 1 patients had lower hazard for rejection with IL‐2RB compared to ATG and NI (p < 0.01), but at the cost of increased risk of infection (5.0 vs. 1.8 vs. 1.6, respectively, at four wk, p < 0.01). Profile 2 patients experienced a fivefold decreased hazard for rejection when treated with IL‐2RB compared with ATG and NI (p < 0.01). In patients at high risk of infection, IL‐2RB reduced risk of rejection but at the expense of increased hazard for infection.     

Fixation of the annulus of the mitral valve with a rigid ring Hemodynamic studies

Currently available prostheses used for replacement of the mitral valve feature a rigid ring for fixation to the annulus of the mitral valve. The effect on the hemodynamics of the left heart of fixation of the annulus of the mitral valve bysuturing a ring from a 1M or a 2M Starr-Edwards valve under cardiopulmonary bypass, leaving the valve leaflets and chordae tendineae intact, was studied in 6 dogs.

Intracardiac and intravascular pressures, cardiac output, and the size of the left ventricle were measured in these animals and a control group of 5 normal dogs in the “resting state” and during induced changes in peripheral vascular resistance (intra-aortic administration of angiotensin II and acetylcholine). Small diastolic pressure differences were detected between the left atrium and the left ventricle in the dogs operated on during the control resting state. These atrial-to-ventricular pressure gradients were greatly increased with the high flow and tachycardia associated with vasodilatation. This increased resistance to flow across the mitral valve constituted the major hemodynamic difference between the two animal groups under the conditions of the study.     

Determination of optimal cryoprotectants and procedures for their addition and removal from human spermatozoa

The objective was to test the hypothesis that the optimal cryoprotective agent for cryopreservation of human spermatozoa would be a solute for which cells have the highest plasma membrane permeability, resulting in the least amount of volume excursion during its addition and removal. To test this hypothesis, theoretical simulations were performed using membrane permeability coefficients to predict optimal procedures for the addition and removal of a cryoprotectant. Simulations were performed using data from four different cryoprotectants: (i) glycerol, (ii) dimethyl sulphoxide, (iii) propylene glycol and (iv) ethylene glycol. Thermodynamic formulations were applied to determine approaches for the addition and removal of 1 M and 2 M final concentrations of cryoprotectant, allowing the spermatozoa to maintain a cell volume within their osmotic tolerance limits. Based on these data, ethylene glycol was predicted to be optimal for minimizing volume excursions among the solutes evaluated. These predictions were then experimentally tested using glycerol as the control cryoprotectant and ethylene glycol as the experimental cryoprotectant. The results indicate that there was a higher (P < 0.05) recovery of motile spermatozoa after cryopreservation when using 1 M ethylene glycol than with 1 M glycerol, supporting the hypothesis that use of the cryoprotectant for which the cell has the highest permeability will result in higher cell survival.      

Donor insemination: Dutch parents' opinions about confidentiality and donor anonymity and the emotional adjustment of their children

Results from a comparative study investigating 38 donor insemination (DI) Dutch families with 4-8 year old children are presented. The aims of this study were to investigate parents' opinions on the issues of confidentiality and donor anonymity, to assess the emotional development of the children, and to examine in DI families the association between secrecy with regard to the use of a donor and the emotional adjustment of the children. The DI families were compared to families with a child conceived by in-vitro fertilization (IVF) and to families with a naturally conceived child. Secrecy appeared to be associated with DI and not with IVF: 74% of the DI parents intended not to inform the child about the way in which she/he was conceived, whereas none of the IVF parents intended to keep the secret. Only one set of DI parents and two sets of IVF parents had actually told the child. As to donor anonymity, a spread of opinions appeared among DI parents; 57% preferred an anonymous donor, 31% would have liked non- identifying information about the donor, 9% preferred the donor's identity to be registered and 3% remained unsure. Parents' major concern was to know more about the medical/genetic background of the donor. Mothers and fathers in the DI families differed in their opinions concerning the issues of confidentiality and donor anonymity: fathers, more often than mothers, were secretive with regard to the use of a donor and husbands, more often than their wives, were in favour of donor anonymity. With regard to the emotional development of the children, more emotional/behavioural problems were revealed among DI children than among children who were naturally conceived. No association was found between secrecy and the emotional/behavioural adjustment of the children.      

Effect of vitamin A adjunct therapy for cerebral malaria in children admitted to Mulago hospital: a randomized controlled trial

Background

Malaria is a leading cause of mortality in Uganda accounting for 25% of deaths among children. Hitherto no adjunct therapy has been identified to improve outcome of cerebral malaria. Retinol suppresses growth of P.falciparum, scavenges free radicals, and exhibits synergistic action with quinine in parasite clearance.

Objective

To determine the effect of vitamin A supplementation on treatment outcome of cerebral malaria

Methods

In this randomised double-blind placebo controlled clinical trial we studied 142 children aged 6–59 months admitted with cerebral malaria in Mulago Hospital, Kampala. Children were randomised to either vitamin A or placebo and followed for 7 days. The main outcome measures were coma recovery time, time for convulsions to stop, and parasite and fever clearance. Secondary outcomes were overall mortality and time taken to start oral feeds.

Results

There was no difference in the coma recovery time (p=0.44), resolution of convulsions (p=0.37), fever clearance (p=0.92), parasite clearance (p=0.12), and starting oral feeds between the two treatment groups. Mortality was higher (16.2%) in the placebo than in the vitamin A group (8.1%): RR 1.4; 95% CI 1.0–2.1.

Conclusions

Vitamin A as adjunct therapy did not significantly reduce coma duration but there were fewer deaths in the vitamin A arm.