Oxygen Reserve Index and Arterial Partial Pressure of Oxygen: Relationship in Open Heart Surgery.

BACKGROUND: Mild to moderate hyperoxia is potentially beneficial to patients undergoing open heart surgery. Oxygen Reserve Index (ORI) is a novel parameter that correlates to arterial oxygen tension (PaO2) in the hyperoxic range. This prospective study aimed to assess whether the relationship between ORI and PaO2 remains intact in the setting of open-heart surgery. METHODS: This study included patients undergoing valve, aortic arch and coronary artery bypass grafting (CABG) surgeries, on and off pump, between September 1st 2019 and August 31st 2021. Enrolled patients had arterial blood gas samples collected and analyzed after induction of anesthesia and increases in FiO2 in steps of 0.08 with ORI being recorded at the time of sample collection for cross reference and analysis. RESULTS: ORI values showed a statistically significant correlation with PaO2 values in the 100-200 mmHg range (r = 0.8193, p < 0.001). Additionally, there was a significant correlation between ORI and SpO2 values in the range of 95% and 100% (r = 0.529, p < 0.05). CONCLUSIONS: The preserved relationship between ORI and PaO2 in the mild and moderate hyperoxic range can allow more precise titration of oxygen therapy to guide therapy targeting normoxia, mildly and moderately hyperoxia. Additionally, it could have a potential use as an early warning system for impeding hypoxia.

Upper mini sternotomy approach for pulmonary artery banding: A single centre experience.

BACKGROUND: Pulmonary artery banding (PAB) remains a crucial technique in modern cardiac surgery. Left lateral thoracotomy, median sternotomy, and left anterior thoracotomy are well-known approaches. With significant scarce reports addressing the application of the upper mini sternotomy approach for PAB, this study aims to share experience and report outcomes of patients operated upon using this approach and its impact on facilitating the redo surgery. PATIENTS AND METHODS: Since 2015, we practiced the use upper mini sternotomy approach for PAB in the study center where we conducted this retrospective study of 22 patients who underwent banding through the upper mini sternotomy approach. Indications varied between complete atrioventricular septal defect, multiple muscular ventricular septal defects, and univentricular heart with increased pulmonary blood flow. RESULTS: At the time of PAB, the medians of age 2.0 (1-4.5) months and bodyweight of 3.1 (1.9-4.2) kg were reported against a surgery time range of 75- 135 min and peak gradient across the band of 54-78 mmHg. There was one unrelated mortality case (4.5%) due to a severe attack of pulmonary hypertensive crisis. Fifteen patients underwent the redo surgery. No mortality or sternotomy-related complications were reported following the second stage surgery while the reopening time ranged between 17 and 32 min. CONCLUSIONS: The upper mini sternotomy approach for PAB is safe and facilitates the subsequent redo surgery and could be a valuable alternative to other surgical approaches.

Three-dimensional transesophageal echocardiography incremental value in a rare case of a bileaflet tricuspid valve.

Detailed assessment of the tricuspid valve using two-dimensional echocardiography is always challenging, as only two of three leaflets can be seen at a time. Three-dimensional echocardiography can provide the enface view of the tricuspid valve that allows simultaneous visualization of all of the three leaflets. In a 42-year-old male patient scheduled for pulmonary endarterectomy, 3DTEE showed that the tricuspid valve is bileaflet, with one septal and another lateral leaflet. There were two commissures, one of them is anteriorly positioned and the other one is posterior. Our findings were confirmed intra-operatively by direct surgical visualization of the tricuspid valve.