The results suggest that low body weight and unplanned emergency surgery are independent risk factors for the death of neonates with CCHD. SPCT is unrelated to the survival rate of neonates with CCHD underwent surgery, but can reduce the incidence of unplanned emergency surgery.
Previous studies showed that a prenatal diagnosis improves the prognosis of infants with CCHD [12, 21, 22]. Indeed, a prenatal diagnosis of CCHD will allow time for discussion with the parents, discussion among specialists [3], and planning the surgery, and the infant will be closely monitored immediately after birth. In this study, fetal ultrasound cardiac abnormality was not independently associated with survival. Still, the available prenatal ultrasound data were not necessarily specific for heart abnormalities, and not all prenatal screenings were performed at the study hospital. In addition, even for children with a prenatal diagnosis, many other factors affect their prognosis, and not all children with a prenatal diagnosis were transferred to our center, and such children were not included in the present study. Nevertheless, some children with CHD diagnosed before delivery have not been referred to our center, especially those far away, and have been treated at a local hospital. All infants with high complexity, who were diagnosed with and treated for CCHD, were ultimately referred to our center, which probably contributed to this study’s relatively high mortality rate. In addition, a missed diagnosis of CCHD will lead to death a few days after birth [23].
In a review by Singh et al. [3], it was suggested that timely treatment with cardiotonic drugs (e.g., prostaglandin E1) and discussion with a pediatric cardiologist could be lifesaving. Wang et al. [19] recently reported an integrated approach for NICU transfer for patients with CCHD that led to shorter diagnosis and hospitalization intervals; surgery could be performed with a lower mortality risk, especially in infants with transposition of great arteries. Peterson et al. [13] and Jegatheeswaran et al. [14] reported that the prognosis of infants with CHD was better in mother and child hospitals than in general hospitals, probably owing to better access to a pediatric cardiologist and experience in CCHD surgery in specialized hospitals. It has been reported that about 20% of infants with CCHD are diagnosed after being discharged from maternity units and that 43% of these infants are in circulatory shock when admitted to a cardiology department [24]. Brown et al. [25] reported that heart failure and end-organ dysfunction were more common in infants with CCHD discharged from obstetrics units than those discharged from cardiology units. Fixler et al. [26] reported that the non-referral of infants with CCHD to cardiac specialty centers led to significant mortality rates. Accordingly, in the present study, all infants who died prior to surgery were in the non-SPCT group, but there were no significant differences after surgery. The transport of children with CCHD is very important to maintain the stability of these children, especially in the case of remote transport distance. All the children who died before the operation occurred in the non-SPCT group, which might be related to the lack of professional cardiac specialist management before or during the transport, leading to life-threatening complications and the loss of surgical opportunities. Non-SPCT transportation, inadequate evaluation of the condition before transportation, and inadequate monitoring and care measures during transportation are all risk factors that lead to the death of children. The transportation process involves the movement of the child and the handling and fixation of the required instruments and equipment, which may lead to the instability of the child’s respiratory system and circulatory system, as well as the occurrence of accidents, thus having a negative impact on the prognosis of the child, Therefore, “transfer” should be started systematically [27]. The basis for the safe development of all transport modes is to stabilize vital signs, provide a safe airway and venous access, ensure the safety of all catheters, and provide appropriate monitoring before departure. As recommended by the American College of Intensive Care Medicine, each hospital should develop its intra-hospital and inter-hospital transfer plans for critically ill patients [28]. Clinical medical staff should develop more accurate transfer strategies based on fully considering the actual clinical environmental factors and the latest evidence and establish specialized transfer teams to benefit children. In addition, SPCT referral was not independently associated with patient outcomes. This lack of association can be due to factors such as age at referral, prematurity, perinatal conditions, and screening.
The present study identified low body weight at surgery and unplanned emergent surgery as factors associated with a poor prognosis in infants with CCHD. Mehmood et al. [29] reported that infants < 2.2 kg undergoing cardiac surgery were at high risk of ICU morbidity and mortality. Oster et al. [30] reported that low birth weight was associated with higher 1-year mortality in infants with CHD and CCHD. Emergent surgery has to be performed in infants with a suddenly deteriorating condition, indicating a more severe condition and a poorer prognosis. Still, the present study showed that SPCT could reduce the incidence of unplanned emergency surgery, which can support the use of SPCT. This study shows that the transport of CCHD critically ill neonates does not affect the survival rate of neonates after surgery. However, the study showed that the safe and effective implementation of transportation could reduce preoperative mortality and emergency surgery, thus providing a reference basis for the transportation of neonates with CCHD and further improving the appropriate surgical opportunity for them.
Regarding the 16 dead neonates, the parents transferred them to our hospital alone, including 3 common Ordinary ambulance transshipment. Some patients with CCHD were in poor condition, had been in cardiogenic shock when they arrived the hospital. Some parents chose to give up DNR (do not resuscitate). Most of the neonates died after rescue and lost the surgical opportunity. The neonates with CCHD were transported by our professional pediatric cardiology specialist, and safe and effective transportation was carried out for these neonates, providing appropriate operation status and timely mechanism.
This study had some limitations. It was a retrospective study limited to the data available in the charts, introducing bias. The patients were from only one center, resulting in a relatively small sample size and possibly leading to bias due to local practices. The exact physician’s line of thought that led to an individual neonate being transferred or not to the SPCT was not always clearly indicated in the charts and could not be analyzed. Prospective multicenter studies with large sample sizes are needed to provide higher-grade evidence.