[Treatment strategy of congenital tracheal stenosis associated with non-vascular ring cardiac malformations].

Objective: To examine the treatment strategy of congenital tracheal stenosis associated with non-vascular ring cardiac malformations. Methods: This is a retrospective case series. Clinic data from 24 children with tracheal stenosis who underwent surgical treatment in the Department of Cardiac Surgery, Children's Hospital Affiliated to Shandong University from February 2017 to March 2023 were retrospectively collected. There were 16 males and 8 females, aged (M(IQR)) 6.5 (19.6) months (range: 2.2 to 66.3 months) and weighted 5.95 (4.76) kg (range: 3.2 to 20.0 kg). All patients had obvious respiratory symptoms. Eighteen patients underwent cardiac malformation correction and tracheoplasty at the same time (simultaneous group). Six patients in the staged operation group were treated with cardiac malformation correction in the first stage operation and tracheoplasty in the second stage operation due to missed diagnosis or delayed diagnosis of tracheal stenosis or no condition for tracheoplasty. Slide tracheoplasty was used to correct tracheal stenosis in both groups. The recovery of the children was followed. Wilcoxon sign rank test was used for comparison between the two groups. Results: There was no death during the perioperative period and hospitalization. In the simultaneous group, 1 case with delayed chest closure underwent bedside chest closure after 52 hours, 2 cases were intubated again after operation, and 1 case was implanted with an endotracheal stent. The duration of mechanical ventilation was 40.5 (39.6) hours (range: 19.0 to 438.8 hours). In the staged group, there was 1 case of re-intubation after operation, combined with left vocal cord paralysis and respiratory multidrug-resistant bacterial infection (Acinetobacter baumanii). One patient underwent 3 times of bronchoscopic balloon dilatation of the right middle bronchus, and heart rate returned to normal range. The duration of mechanical ventilation was 19.0 (21.4) hours (range: 17.1 to 96.7 hours). During follow-up, a patient in the simultaneous group was prone to respiratory infection and had good exercise tolerance, 1 patient in the staged group still had sputum stridor in the throat 3 months after the operation, and symptoms improved significantly 6 months after the operation. The other children didn't have obvious respiratory symptoms. Conclusions: The diagnosis of tracheal stenosis may be delayed or missed when tracheal stenosis is complicated by non-vascular ring cardiac malformations. One-stage correction of tracheal stenosis and cardiac malformation can achieve a good outcome.

[Surgical treatment strategy of pulmonary artery sling: a series of 110 cases].

Objective: To examine the effect of surgical treatment in children with pulmonary artery sling and the surgical treatment strategy. Methods: Relevant data of 110 children with pulmonary artery sling admitted to the Department of Cardiac Surgery, Children's Hospital Affiliated to Shandong University from February 2017 to July 2022 were retrospectively analyzed. There were 55 males and 55 females, aging (M(IQR)) 9.0 (10.6) months (range: 1 to 96 months). The weight was 7.8 (3.5) kg (range: 2.5 to 25.0 kg). Of the 110 patients, 108 had different degrees of tracheal stenosis and 2 had normal trachea. Left pulmonary artery transplantation and tracheoplasty were performed in 78 patients. Left pulmonary artery transplantation was performed in 30 patients (11 in our hospital and 19 in other hospitals) due to the lack of an early tracheoplasty technique, in which 24 patients needed stage Ⅱ tracheoplasty due to obvious respiratory symptoms and limited activity endurance, and 6 cases did not intervene. Two children with normal trachea only underwent left pulmonary artery transplantation. Results: Among the 78 children who underwent surgery in the same period, 70 cases recovered smoothly after surgery, of whom respiratory symptoms were significantly reduced or disappeared during the 1 to 65 months follow-up, with similar activity endurance to normal children of the same age. Eight cases died, including 4 cases of postoperative multi-drug resistant bacteria infection, died from tracheal anastomotic opening or septic shock, 1 cases with severe congenital heart disease died from postoperative low cardiac output syndrome difficult to correct, 1 case died from blood pressure could not be maintained due to the compressed left pulmonary artery after transplantation, 2 cases of postoperative digestive system diseases (adhesive intestinal obstruction, gastrointestinal bleeding, etc.). The 24 patients in the staging group were followed for 1 to 84 months. All patients needed stage Ⅱ tracheoplasty due to respiratory symptoms and decreased endurance to activity. Eight cases of the non-intervention tracheal group were successfully separated from the ventilator, cured and discharged in a short period of time. Conclusions: Most children with pulmonary artery sling have tracheal stenosis. Children with low degree of tracheal stenosis and inconspicuous respiratory symptoms can only undergo left pulmonary artery transplantation by lateral thoracotomy. For patients combined with severe tracheal stenosis or obvious respiratory symptoms, a simultaneous left pulmonary artery transplantat and tracheoplasty is recommended.

Comparison of Aortobifemoral Bypass and Endovascular Treatment for Chronic Infrarenal Abdominal Aortic Occlusion From the CHAOS (CHronic Abdominal Aortic Occlusion, ASian Multicenter) Registry.

PURPOSE: To directly compare the clinical outcomes of aortobifemoral bypass surgery (ABF) and endovascular treatment (EVT) for chronic total occlusion (CTO) of the infrarenal abdominal aorta (IAA). MATERIALS AND METHODS: In this retrospective, multicenter study, we used an international database of 436 patients who underwent revascularization for CTO of the IAA between 2007 and 2017 at 30 Asian cardiovascular centers. After excluding 52 patients who underwent axillobifemoral bypass surgery, 384 patients (139 ABFs and 245 EVTs) were included in the analysis. Propensity score-matched analysis was performed to compare clinical results in the periprocedural period and the long-term. RESULTS: Propensity score matching extracted 88 pairs. Procedure time (ABF; 288 [240-345] minutes vs EVT; 159 [100-205] minutes, p<0.001) and length of hospital stay (17 [12-23] days vs 5 [4-13] days, p<0.001) were significantly shorter in the EVT group than in the ABF group, while the proportions of procedural success (98.9% versus 96.6%, p=0.620), complications (9.1% versus 12.3%, p=0.550), and mortality (2.3% versus 3.8%, p=1.000) were not different between the groups. At 1 months, ABI significantly increased more in the ABF group for both in a limb with the lower (0.56 versus 0.50, p=0.018) and the higher (0.49 versus 0.34, p=0.001) baseline ABI, while the change of the Rutherford category was not significantly different between the groups (p=0.590). At 5 years, compared with the EVT group, the ABF group had significantly better primary patency (89.4±4.3% versus 74.8±4.3%, p=0.035) and survival rates (86.9±4.5% versus 66.2±7.5%, p=0.007). However, there was no significant difference between the groups for secondary patency (100.0%±0.0% versus 93.5%±3.9%, p=0.160) and freedom from target lesion revascularization (TLR) (89.3±4.3% vs 77.3±7.3%, p=0.096). CONCLUSION: Even with recent advancements in EVT, primary patency was still significantly better for ABF in CTO of the IAA. However, there was no difference between the groups in terms of secondary patency and freedom from TLR at 5 years. Furthermore, there was no difference in procedural success, complications, mortality, and improvement in the Rutherford classification during the periprocedural period, with significantly shorter procedure time and hospital stay in the EVT group.

Uptake and distribution of halothane in dog blood.

The uptake and distribution of halothane in dog blood were studied by analysing the whole blood and plasma concentrations of halothane in samples of arterial and mixed venous blood at different times after the induction of anesthesia with constant inspired halothane levels of 1.0, 1.5, 2.0, and 2.5%, respectively. In general a steady state was reached 2-3 h after induction. Comparison of the arterial blood concentration calculated from end-tidal halothane partial pressure with that determined by direct analysis of the blood indicated that halothane in the alveoli and halothane in arterial blood are not in thermodynamic equilibrium. The arterial halothane concentrations calculated from the end-tidal halothane partial pressure assuming equilibrium is much higher than those found experimentally; thus end-tidal halothane partial pressure is not a true measure of blood halothane concentration. The distribution of halothane between the plasma and cells in blood appeared to be sufficiently rapid to be independent of the approach to the steady state.

Solubility and distribution of halothane in human blood.

The interactions of halothane with five major constituents of human blood were studied by equilibrium dialysis. Haemoglobin, albumin, red cell membranes and triglycerides were found to contribute significantly to the solubility, and thus the transport, of halothane in whole blood. At physiological concentrations, gamma-globulin had no detectable effect on the solubility of halothane. Absorption isotherms of halothane binding to haemoglobin and albumin suggest a possible positive co-operative effect, but complete saturation of the binding sites was not observed even when the aqueous phase was saturated with halothane. The number of halothane molecules bound per albumin molecule was not significantly affected by the presence of oleic acid. For red cell ghosts and triglyceride-rich micelles (chylomicrons and very low density lipoprotein), the adsorption isotherms suggested that halothane is solubilized within the hydrophobic regions. The distribution of halothane between cells and plasma calculated from the above equilibrium dialysis results was in reasonable agreement with the distribution in whole blood determined by an independent method.

Routine direct injection gas--liquid chromatographic procedure for the analysis of volatile halogenated anaesthetics in whole blood using a new external injection port.

This communication describes the design and construction of a new external injection port for the direct gas--liquid chromatographic analysis of volatile compounds in whole blood. Aliquots (4--40 microliter) of EDTA anti-coagulated blood containing the volatile compound and a weighed quantity of the internal standard, isobutanol, were injected into the disposable glass wool filter of the carrier gas stream directly onto the chromatographic column. Typical data are presented from chromatography performed with dual 6 ft. x 2 mm I.D. glass columns containing Chromosorb 101 programmed from 110--180 degrees at 6 degrees/min and the external injection port maintained at 180 degrees. The method eliminated the problems usually associated with direct injection methods and permitted the accurate analysis of halothane, methoxyflurane, diethyl ether and ethanol over the approximate range 1--100 mg%. Using this analytical procedure the distribution of halothane between the cells and plasma of human blood at 4 degrees was found to be 2.0 +/- 0.2.