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within oxygenators [ 7 ]. 39 people from the survey said they do not use arterial filters and 1 said they do not use it 80 % of the time. Thus, from a total of 66 people from the survey 60 people often do not use some sort of arterial filter whether incorporated or separate.
Central and mixed venous oxygen saturation monitoring has been known for guiding hemodynamic management in major surgeries. In paediatric cardiac surgery, perioperative goal-directed therapy with continuous ScVO 2 monitoring is associated with excellent early survival and a low incidence of organ failure.
Low values of venous oxygen saturation during CPB are generally interpreted as an increased peripheral oxygen-extraction rate due to an oxygen delivery( DO 2) inadequate to sustain the oxygen consumption( VO 2). If DO 2 falls below a critical value, settled at around 260 mL / min / m. a progressive increase of blood lactate is found, a marker of anaerobic energy production.
Rannucietaldidastudylookingat256patientsinpaediatric cardiac surgery and their venous saturations and lactate levels. They found for ScVO 2 values below 68 %, with a significant increase of peak lactate during CPB predicted postoperative major morbidity. Patients who did not experience low values of ScVO 2 and / or high values of peak lactate had an outcome free from adverse events in the great majority of the cases. This demonstrates the importance of measuring venous saturations during CPB. Only a quarter of survey respondents use venous saturation monitor in their centres. Venous Saturation monitoring measures the balance between oxygen delivery and demand of the patient. A statistically significant association between the S v O 2 levels during CPB and 3-year survival after cardiac surgery has been seen demonstrating the potential benefits from such monitoring as it can flag up oxygen imbalances which may arise in surgery [ 8, 9 ].
Similarly, cerebral saturation monitoring is essential as it directly monitors the brains saturation. There was limited use of cerebral saturation monitoring found in this survey’ s population 23.1 % people. Monitoring is crucial for preventing neurological complications during CPB. It has been shown that maintaining an intact autoregulatory activity during CPB collectively with monitoring regional cerebral oxygen saturation will collectively contribute to optimization of patient care during CPB [ 10 ].
In recent years, near-infrared spectroscopy( NIRS) has been proposed as a surrogate of venous saturations in the setting of pediatric cardiac surgery. The main advantages are the continuous monitoring during and after the operation. The preoperative NIRS-derived regional oxygen saturation( rSO 2) levels of < 50 % have been associated with an increased mortality in children undergoing congenital heart surgery. Demonstrating its usefulness [ 9 ].
The report from AmSECT’ s International Consortium highlights essential minimum standards for perfusion practice. It recommends the routine use of safety devices like bubble detectors, level sensors, and arterial filters with audible and visual alarms to enhance patient safety. Continuous monitoring of key parameters, including arterial and venous pressures, SvO 2, hematocrit, and blood gases, is crucial for maintaining perfusion quality. The report also emphasizes the importance of standardized institutional protocols, comprehensive procedural documentation, active participation in quality assurance programs, and regular maintenance of equipment to ensure reliability and safety in clinical practice [ 11 ].
According to the EACTS / EACTA / EBCP guidelines on cardiopulmonary bypass in adult cardiac surgery, it is strongly recommended to incorporate several key monitoring and safety features during CPB to enhance patient outcomes. A bubble detector should be used on all inflow lines to prevent air embolism, classified as Class I, Level C evidence. Continuous monitoring of mixed venous oxygen saturation( SvO 2) and hematocrit( HCT) levels are essential to ensure adequate oxygen delivery and perfusion, supported by Class I, Level B evidence. The use of a level sensor is also recommended during procedures utilizing a( hard-shell) reservoir to monitor reservoir levels and prevent air from entering the circuit, classified as Class I, Level C evidence. Additionally, cerebral monitoring using near-infrared spectroscopy( NIRS) is advised, particularly in high-risk cases, to assess cerebral perfusion and oxygenation, classified as Class IIb, Level B evidence. Implementing these measures aligns with international guidelines and represents best practices for safety and quality in perfusion care [ 12 ].
A survey article by Anyasius Rutto et al. also highlights similarcritical challenges in Kenya and and provides recommendations for improving perfusion practices. It identifies a limited use of essential safety devices such as bubble detectors, level sensors, and arterial filters, raising concerns about patient safety during CPB procedures. The survey emphasizes a significant gap in formal training and certification for perfusionists, recommending the implementation of standardized education programs. It also underscores the absence of national guidelines and protocols, advocating for the development and adoption of comprehensive standards to ensure uniform safety practices. Resource constraints, including limited funding and availability of equipment, were noted as key barriers, with a call for increased collaboration between stakeholders and advocacy for resource allocation. These findings provide a roadmap for addressing safety, education, and resource challenges in perfusion practices, particularly in low-resource settings [ 13 ].
The barriers to consistent use of safety equipment, such as the availability of disposables and equipment, need to be addressed to ensure that all patients receive the highest standard of care. The survey results provide a nuanced view of the adherence to safety standards among perfusionists in Pakistan, revealing a landscape of mixed practices during cardiopulmonary bypass( CPB). Notably, the majority of respondents adhere to certain safety protocols, such as the routine use of bubble detectors and the monitoring of continuous venous saturation. These measures are critical for detecting air in the circuit and assessing the adequacy of oxygen delivery to the body, respectively, thus playing vital roles in ensuring patient safety during CPB. However, the survey highlights concerning gaps in the adoption of other safety technologies. A significant number of perfusionists reported not consistently using level detectors or cerebral saturation monitoring. while cerebral saturation monitors provide real-time data on brain oxygenation, serving as a crucial indicator of cerebral perfusion adequacy. The inconsistent use of these technologies suggests a potential risk area that could impact patient outcomes during Cardiac surgery in Pakistan.