Clinical-Physiological Considerations in Patients Undergoing Staged Palliation for a Functionally Single Ventricle

Assessment of Phenobarbital Administration to Reduce Opioid and Benzodiazepine Use in the Immediate Postoperative Period Following Stage 2 Single-Ventricle Palliation

OBJECTIVE

The Glenn procedure may lead to the development of elevated cerebral venous pressures, which is believed to result in "Glenn headaches." This manifests as excessive irritability, often requiring significant use of opioids and benzodiazepines. This study was designed to report our experience with the use of phenobarbital in the postoperative phase after the Glenn procedure.

METHODS

We performed a retrospective chart review to compare Glenn patients before and after implementation of a sedation protocol using phenobarbital. The 2 groups were compared for demographics, surgical characteristics, and cumulative sedation usage. Correlation coefficients between the preoperative catheterization variables and sedation usage were also calculated.

RESULTS

Groups A (pre-phenobarbital; n = 8) and B (post-phenobarbital; n = 11) were comparable in terms of demographics, cardiac anatomy, preoperative catheterization data, and hemodynamics. Patients in Group B received a median dose of 21.8 mg/kg of phenobarbital during their ICU stay. Although there was a decreased administration of morphine equivalents (2.60 mg/kg vs 2.25 mg/kg, p = 0.38), benzodiazepine (0.1 mg/kg vs 0.074 mg/kg, p = 0.43), and dexmedetomidine (47 mcg/kg vs 37.2 mcg/kg, p = 0.53) in Group B, the differences were not statistically significant. There was also no strong correlation between preoperative hemodynamic variables and the postoperative sedation requirement, and there was no statistically significant difference in overall outcomes between the 2 groups.

CONCLUSIONS

While phenobarbital may have mitigated the use of opioids, benzodiazepines, and alpha-agonist agents in some postoperative Glenn patients, the overall findings for all patients were not statistically significant. Further prospective studies are needed to ascertain the role of phenobarbital in these patients.

Heart failure in single right ventricle congenital heart disease: physiological and molecular considerations

Because of remarkable surgical and medical advances over the past several decades, there are growing numbers of infants and children living with single ventricle congenital heart disease (SV), where there is only one functional cardiac pumping chamber. Nevertheless, cardiac dysfunction (and ultimately heart failure) is a common complication in the SV population, and pharmacological heart failure therapies have largely been ineffective in mitigating the need for heart transplantation. Given that there are several inherent risk factors for ventricular dysfunction in the setting of SV in addition to probable differences in molecular adaptations to heart failure between children and adults, it is perhaps not surprising that extrapolated adult heart failure medications have had limited benefit in children with SV heart failure. Further investigations into the molecular mechanisms involved in pediatric SV heart failure may assist with risk stratification as well as development of targeted, efficacious therapies specific to this patient population. In this review, we present a brief overview of SV anatomy and physiology, with a focus on patients with a single morphological right ventricle requiring staged surgical palliation. Additionally, we discuss outcomes in the current era, risk factors associated with the progression to heart failure, present state of knowledge regarding molecular alterations in end-stage SV heart failure, and current therapeutic interventions. Potential avenues for improving SV outcomes, including identification of biomarkers of heart failure progression, implications of personalized medicine and stem cell-derived therapies, and applications of novel models of SV disease, are proposed as future directions.

Health-related quality of life in paediatric patients with congenital heart defects: association with the type of heart defect and the surgical technique

The aim of the study was to investigate the impact of a number of surgical interventions for a various congenital cardiac defects (CHDs) on self-reported HRQoL.

METHODS

Patients who had received corrective surgery of several congenital heart defects (surgical VSD closure, Fallot, TGA after atrial or arterial switch or Fontan-type circulation for univentricular AV-connection) were interviewed in the office of their home peadiatric cardiologist. HRQoL in children along 7 dimensions was assessed using a standardised questionnaire (PEDQoL); information on the medical case history of each respondent was also collected.

STATISTICS

HRQoL was assessed in the questionnaire by asking about the frequency (never, rarely, often, always) of specific negative experiences; more frequent experiences indicate a lower quality of life. Frequency expressions were transformed into numerical values (25, 50, 75, 100%), and mean values for HRQoL were calculated for each patient and for each domain. Differences in HRQoL among patients with different types of interventions were analysed using the Mann-Whitney Test or the Kruskal-Wallis Test as appropriate; p values <0.05 were considered to indicate significant differences, while p values <0.1 were considered to indicate notable trends.

RESULTS

Patients: 169 patients (60% male, 40% female) were part of the study. The mean age was 11.6 years; 50 patients had surgical VSD closure, 52 surgeries for Tetralogy of Fallot (22 transannular patch, 18 no transannular patch, 12 inaccurate description), 40 had complete transposition of the great arteries (28 atrial switch, 12 arterial switch), 22 had a Fontan-type procedure for univentricular AV-connection. HRQoL differed little among patients with different CHDs for the items "relation to friends," "interactions in the affected families", and "own body image". For other items, notable differences emerged: patients with univentricular hearts rated their physical capacity worse and showed a tendency towards negative ratings in other domains. On the other hand, patients after Fallot or TGA correction tended to rate their HRQoL in several domains as relatively high. Focusing on the mode of surgery for Fallot repair, respectively, TGA correction the only significant difference was found for "physical capacity" in TGA (atrial vs. arterial repair). Mustard patients tended to rate most items worse. Physical capacity was rated worst by patients with a Fontan circulation. Repeated surgery led to lower ratings for all domains except "physical capacity" and "body image".

CONCLUSIONS

Different surgical techniques for CHD do not affect children's and adolescents' self-reported HRQoL to the extent that one would expect. This observation is in line with observations in groups of children with different chronic diseases. Specialised psychosocial support is necessary in order to maintain this positive self-evaluation and to ensure patients are able to lead autonomous personal and professional lives.