Effects of protocol-based management on the post-operative outcome after systemic to pulmonary shunt

Pulmonary reperfusion injury in post-palliative intervention of oligaemic cyanotic CHD: a new catastrophic consequence or just revisiting the same old story?

Pulmonary reperfusion injury is a well-recognised clinical entity in the setting pulmonary artery angioplasty for pulmonary artery stenosis or chronic thromboembolic disease, but not much is known about this complication in post-palliative intervention of oligaemic cyanotic CHD. The pathophysiology of pulmonary reperfusion injury in this population consists of both ischaemic and reperfusion injury, mainly resulting in oxidative stress from reactive oxygen species generation, followed by endothelial dysfunction, and cytokine storm that may induce multiple organ dysfunction. Other mechanisms of pulmonary reperfusion injury are "no-reflow" phenomenon, overcirculation from high pressure in pulmonary artery, and increased left ventricular end-diastolic pressure. Chronic hypoxia in cyanotic CHD eventually depletes endogenous antioxidant and increased the risk of pulmonary reperfusion injury, thus becoming a concern for palliative interventions in the oligaemic subgroup. The incidence of pulmonary reperfusion injury varies depending on multifactors. Despite its inconsistence occurrence, pulmonary reperfusion injury does occur and may lead to morbidity and mortality in this population. The current management of pulmonary reperfusion injury is supportive therapy to prevent deterioration of lung injury. Therefore, a general consensus on pulmonary reperfusion injury is necessary for the diagnosis and management of this complication as well as further studies to establish the use of novel and potential therapies for pulmonary reperfusion injury.

Outcomes of Infants Undergoing Modified Blalock-Taussig Shunt Procedures in Oman: A retrospective study

Objectives

A modified Blalock-Taussig (mBT) shunt procedure is a common palliative surgery used to treat infants and children with cyanotic congenital heart disease (CCHD). This study aimed to report the outcomes of infants and children undergoing mBT shunt procedures in Oman. In addition, risk factors associated with early mortality, inter-stage mortality and reintervention were assessed.

Methods

This retrospective cohort study was conducted from January 2016 to December 2018 at the National Heart Centre, Muscat, Oman. All paediatric patients with CCHD undergoing mBT shunt procedures as a primary palliative procedure during this period were included. Data were retrieved from electronic hospital records. Kaplan-Meier survival curves were used to describe overall survival.

Results

A total of 50 infants and children were included in this study. The in-hospital mortality and interstage mortality rates were 10% and 6.7%, respectively. Preoperative mechanical ventilation (odds ratio [OR] = 3.00, 95% confidence interval [CI]: 1.98–4.76; P = 0.007) and cardiopulmonary bypass (OR = 4.09, 95% CI: 2.44–6.85; P = 0.002) were significant risk factors for early mortality. In-hospital and interval surgical reintervention rates were 12% and 13.3%, respectively. Following the primary shunt procedure, the median time to second-stage surgery was 15.5 months (range: 5.0–34.0 months).

Conclusion

The findings of this study support those reported in international research regarding the risks associated with mBT shunt surgeries. In particular, preoperative mechanical ventilation and cardiopulmonary bypass were significant risk factors for early mortality.