Does Down syndrome influence the outcomes of congenital cardiac surgery? A systematic review and meta-analysis

BACKGROUND

Congenital cardiac surgery for individuals with Down syndrome (DS) has historically occurred at a reduced frequency. Little data are available regarding long-term post-congenital cardiac surgical outcomes. Limited sample sizes and clinical heterogeneity require a pooled analysis approach.

AIMS

To compare long-term outcomes post-congenital heart surgery between adults with and without DS.

METHODS

Databases (Medline, Embase, and PubMed) were searched utilizing terms related to DS and congenital heart disease.Studies that enrolled adults (>18 years) with operated congenital heart disease and compared long-term outcomes with respect to DS presence were included. All study designs were included, but those with limited/peri-operative follow-up, non-English texts, case studies, and literature reviews were excluded.Blinded screening, data extraction, and quality assessment were independently conducted by two reviewers. QUIPS criteria were used for risk of bias analysis. Both random- and fixed-effects models were used for meta-analysis.

RESULTS

A total of 23 studies (n = 10 466) were included. Risk of bias was frequently high due to unblinded retrospective study designs and analyses limited in adjustment for other prognostic factors.Meta-analysis demonstrated no effect of DS on long-term mortality [hazard ratio (HR) 0.86, 95% confidence interval (95% CI) 0.6-1.23], to a maximum described follow-up of 38 years. Lower cardiac reoperation risk (HR 0.6, 95% CI 0.46-0.78) for individuals with DS was found on pooled analysis. Meta-analysis was limited by between-study variation.

CONCLUSION

DS does not affect post-congenital cardiac surgical survival in adulthood. Reduced reoperation may reflect challenges in assessing functional and symptomatic status and/or concerns regarding perceived reoperation difficulties or likely benefits.

Impact of mechanical stress on flexible tubing used for biomedical applications: Characterization of the damages and impact on the patient's health

Flexible tubing is a key part of a lot of medical devices used in hospital, but may be subjected to a lot of various mechanical stresses that can led to the failure or to complications for the patients. The nature and causes of these mechanical stresses were listed for peristaltic pump tubing, infusion set tubing and catheters. Their consequences in term of tubing damages and particular contamination were reported. The impact of the chemical nature of the tubing, of its size and also the impact of various parameters of the clinical acts were reviewed. Last the consequences for the patient's health were discussed.

Multicenter International Survey on Cardiopulmonary Bypass Perfusion Practices in Adult Cardiac Surgery

OBJECTIVES

To assess current practice in adult cardiac surgery during cardiopulmonary bypass (CPB) across European and non-European countries.

DESIGN

International, multicenter, web-based survey including 28 multiple choice questions addressing hemodynamic and tissue oxygenation parameters, organ protection measures, and the monitoring and usage of anesthetic drugs as part of the anesthetic and perfusion practice during CPB.

SETTING

Online survey endorsed by the European Association of Cardiothoracic Anesthesiologists.

PARTICIPANTS

Representatives of anesthesiology departments in European and non-European adult cardiac surgical centers.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The survey was distributed via e-mail to European Association of Cardiothoracic Anesthesiologists members (n = 797) and kept open for 1 month. The response rate was 34% (n = 271). After exclusion of responses from the same centers and of incomplete answers, data from 202 cardiac centers in 56 countries, of which 67% of centers were university hospitals, were analyzed. Optimization of pump flows and tissue oxygenation parameters during CPB were applied by the majority of centers, with target flow rates of >2.2 L/min/m² in 93% (n = 187) of centers and mean arterial blood pressures between 51 and 90 mmHg in 85% (n = 172). Hemoglobin transfusion triggers were either individualized or between 7 and 8 g/dL in 92% (n = 186) of centers. Mixed venous oxyhemoglobin saturations were assessed routinely in 59% (n = 120) and lactate in 88% (n = 178) of cardiac surgery units. Noninvasive cerebral saturation monitoring was used in a subgroup of patients or routinely in 84% (n = 169) of sites, and depth-of-anesthesia monitoring was used routinely in 53% (n = 106). Transesophageal echocardiography and pulmonary artery catheters were used routinely or in subgroups of patients in 97% (n = 195) and 71% (n = 153) of centers, respectively. The preferred site for temperature monitoring was the nasopharynx in 66% (n = 134) of centers. Anesthetic techniques were variable, with 26% of centers (n = 52) using low-tidal-volume ventilation and 28% (n = 57) using continuous positive airway pressure during CPB. Volatile agents were used routinely as the only agent during CPB in 36% sites (n = 73) and propofol in 47% (n = 95). Other drugs routinely administered included magnesium in 45% (n = 91), steroids in 18% (n = 37), tranexamic acid in 88% (n = 177), and aprotinin in 15% (n = 30) of the centers.

CONCLUSION

This international CPB survey revealed that techniques for optimization of pump flow and oxygenation during CPB usually were applied. Furthermore, cerebral and hemodynamic monitoring devices were frequently used during CPB. However, most CPB-related anesthetic techniques and medications were more variable. More high-quality randomized controlled trials are needed to assess anesthetic techniques and organ protection.

Pulsatile Versus Nonpulsatile Flow During Cardiopulmonary Bypass: Extent of Hemolysis and Clinical Significance

Pulsatile flow has been used during cardiopulmonary bypass (CPB) for decades and its use is increasing with advancing extracorporeal technology. Pulsatile flow generates higher circuit pressures and shear forces than nonpulsatile flow at comparable pump flow and patient mean arterial pressure. Very little is known about the effect this has on erythrocytes. We included 62 adult patients (32 in the pulsatile group and 30 in the nonpulsatile group) undergoing elective coronary artery bypass grafting in this prospective observational study. Blood samples were collected at routine sampling times throughout surgery and were analyzed for the presence of free heme and globin using mass spectroscopy. Patient characteristics, CPB, and aortic cross-clamp times, pump flow as well as patient mean arterial pressure were similar in both groups. Maximum circuit pressure in the pulsatile flow group was statistically significantly higher than that in the nonpulsatile flow group (257.12 vs. 190.64 mmHg, p < 0.0001). Both heme and globin levels were higher in the pulsatile flow group. This reached statistical significance with globin at 30 minutes of CPB and with heme after aortic unclamping. We conclude that pulsatile CPB using roller pumps results in a greater extent of hemolysis. The clinical significance, however, is not yet known.

Endotoxemia related to cardiopulmonary bypass is associated with increased risk of infection after cardiac surgery: a prospective observational study

Introduction

Previous studies have documented a high frequency of endotoxemia associated with cardiopulmonary bypass (CPB). Endotoxemia may be responsible for some of the complications associated with cardiac surgery. The purpose of the study was to examine the prevalence of endotoxemia during cardiopulmonary bypass supported aortocoronary bypass grafting surgery (ACB) using a new assay, the Endotoxin Activity Assay (EAA), and explore the association between endotoxemia and post-operative infection.

Methods

The study was a single center prospective observational study measuring EAA during the perioperative period for elective ACB. Blood samples were drawn at induction of anesthesia (T1), immediately prior to release of the aortic cross-clamp (T2), and on the first post-operative morning (T3). The primary outcome was the prevalence of endotoxemia. Secondary outcomes assessed included infection rates, intensive care unit (ICU) and hospital length of stay. An EAA of < 0.40 units was interpreted as "low", 0.41 to 0.59 units as "intermediate", and ≥0.60 units as "high".

Results

A total of 57 patients were enrolled and 54 patients were analyzable. The mean EAA at T1 was 0.38 +/- 0.14, at T2 0.39 +/- 0.18, and at T3 0.33 +/- 0.18. At T2 only 13.5% (7/52) of patients had an EAA in the high range. There was a positive correlation between EAA and duration of surgery (P = 0.02). In patients with EAA ≥0.40 at T2, 26.1% (6/23) of patients developed post-operative infections compared to 3.5% (1/29) of those that had a normal EAA (P = 0.0354). Maximum EAA over the first 24 hours was also strongly correlated with risk of post-operative infection (P = 0.0276).

Conclusions

High levels of endotoxin occur less frequently during ACB than previously documented. However, endotoxemia is associated with a significantly increased risk of the development of post-operative infection. Measuring endotoxin levels during ACB may provide a mechanism to identify and target a high risk patient population.