General data
This study included 82 children with CDH who were admitted to our hospital from 2015 to 2018. The children diagnosed with CDH were evaluated and treated with tracheal intubation ventilator support before cord clamping. Twelve patients died of severe disease before surgery. After adjusting electrolytes, acid-base balance, coagulation function and circulatory support, the other 70 cases underwent diaphragmatic herniorrhaphy. Among them, 26 cases received thoracoscopic-assisted diaphragmatic hernia repair (observation group) and 44 cases received open diaphragmatic hernia repair (control group), according to the opinions of the patient’s family and the patient’s condition. The family of each patient signed the informed consent form, and the study was approved by the Ethics Committee of Linyi Central Hospital (No. 2015013001).
Inclusion criteria: Comply with Canadian Clinical Practice Guide 2018: Diagnosis and Management of Congenital Diaphragmatic Hernia; Apgar score > 4; recover vital signs after rescue in spite of ischemia and hypoxia [10, 11].
Exclusion criteria: Newborns who failed to be rescued; children with congenital central nervous system malformation, serious digestive system malformation, severe cardiovascular malformation, such as congenital heart disease, including atrial septal defect, ventricular septal defect, patent ductus arteriosus, patent foramen ovale, and various degrees of pulmonary hypertension; children with non-cyanotic congenital heart disease with small defects; and children with more complicated, cyanotic congenital heart disease who were not suitable for thoracoscopic surgery.
Intraoperative management
General anesthesia was performed with endotracheal intubation using the trachea cannula without cuff (Xintaike, China). At birth, tracheal intubation, mechanical ventilation and nasogastric tube placement were performed before umbilical cord disconnection, and then the child was transferred to pediatric surgical intensive care unit for ventilator therapy. A series of preoperative examinations were performed, including echocardiography, arterial blood gas and electrolytes, and chest radiography. After the child entered the operating room, the trachea catheter was connected to the anesthetic machine (Bori 700D, Probe, Shenzhen) for mechanical ventilation. After confirming that the tracheal tube was placed in the trachea, pressure support mode was utilized. Inspiratory pressure and respiratory frequency were adjusted according to the end-tidal carbon dioxide (ETCO2) value and pulse oxygen saturation (SpO2). And at the same time, invasive arterial manometry and deep vein catheterization via internal jugular vein were performed. Anesthesia-inducing drugs include 0.02 mg/kg atropine (Hubei Xinrunde Chemical Co., Ltd., Hubei), 0.1 mg/kg midazolam (Jiangsu Nhwa Pharmaceutical Co., Ltd., Jiangsu), 2 mg/kg propofol (Fresenius Kabi, Beijing), 0.2 mg/kg Atracurium Cisatracurium besilate (Chongqing Saipunasi Technology Co., Ltd., Chongqing), and 1–2 μg/kg fentanyl (Yichang Humanwell Pharmaceutical Co., Ltd., Fujian). Anesthesia was maintained by inhalation of sevoflurane (2–2.5%) and intravenous pumping of remifentanil (0.1–0.3 μg/kg/min). The ventilator controlled respiration using pressure control mode. The inspiratory pressure was 15–20 cmH2O, the respiratory rate was 20–24 times / min, and the breathing ratio was 1:2. Depending on the situation, a positive end expiratory pressure of 1–4 cmH2O could be used. The intraoperative parameter was adjusted according to ETCO2 which should be maintained at 35–60 mmHg. The intraoperative artificial pneumothorax pressure was set at approximately 2–6 mmHg, and the gas flow rate was approximately 1.5–2 L/min. When SpO2 < 90% or ETCO2 > 60 mmHg, manual manipulation was performed to maintain the respiratory rate at 20–35 times / min, the peak inspiratory pressure at < 30 mmHg, and the mean airway pressure at < 6 mmHg until the conditions above were improved. Endotracheal catheters of all patients were reserved and patients were transferred to pediatric surgical intensive care unit for continued ventilator support.
Operation methods
Control group: The children were given general anesthesia, 5–8 cm transverse incision was made under the rib margin of the left upper abdomen. After opening the abdomen, the internal organs entering the thoracic cavity were repositioned, and the defect margin was sutured by intermittent mattress suture after fully exposing the defect area of the diaphragm. If there was a hernia sac, it should be resected. After the operation, according to the actual situation of the child, determine whether the drainage tube needs to be detained, close the chest and return to the intensive care unit.
Observation group: The children underwent general anesthesia with tracheal intubation. The children took the head high and feet low, the right side lying position, and the left upper arm raised to ensure the elevation of the subscapular angle to the fifth intercostal plane. Three Trocars were placed in the middle of the umbilical cord and in the left and right upper abdomen. Then, with the help of pneumothorax pressure and manipulation forceps, the hernia contents were repositioned to the abdominal cavity, and the diaphragm defect was fully exposed in order to observe the size of the diaphragm defect. If there is a hernia sac in the child, push it to the abdominal side, and then use 2–0 non-absorbable needle suture to suture the defect diaphragm intermittently. The patch uses a new type of lightweight ultrapro hernia system (UHS) device to suture the defect from both sides of the small tension to the middle. After suturing, the operating instruments were pulled out, the incision was sutured, and the tracheal intubation was removed after the patient was awake and in stable situation.
Observation indicators
Main observation indicators: Postoperative respiratory complications, incidence of pulmonary hypertension, postoperative mechanical ventilation duration, antibiotic use duration, hospital stay, postoperative survival rate and recurrence rate.
Secondary observation indicators: Number of cases of cardiac malformation combined with pulmonary hypertension, preoperative mechanical ventilation adjusted blood gas, and intraoperative manual ventilation.
Successful operation: X-ray examination showed complete repair of hernia sac; the whole lung volume and effective lung volume decreased while the residual volume increased; pulmonary artery pressure was normal.
Postoperative recurrence: Complications such as hernia sac protrusion, pulmonary volume increase, cardiovascular malformation, etc.
The lung to head ratio (LHR) is an indicator for assessing and predicting fetal prognosis. LHR = (right lung long diameter × right lung short diameter) / head circumference. If LHR > 1.4, the prognosis for the child is good; a LHR < 1.0 indicates severe CDH and poor prognosis.
An arterial blood PH < 7.3 or PaCO2 > 60 mmHg indicates hypoxia, acidic blood and severe diaphragmatic hernia.
Statistical method
SPSS 22.0 statistical software was used for analysis. The measurement data were expressed as mean ± standard deviation (\( \overline{x} \) ± sd). Two sample t test was used for inter-group comparison, and one-way ANOVA was used for intra-group comparison at different time points. Enumeration data were expressed as case / percentage (n/%) and tested by χ2 test or Fisher’s exact test. P < 0.05 was considered statistically significant.