The primary aim of our study is to leverage lung ultrasound to assess and identify postoperative pulmonary complications following shoulder arthroscopic surgery and the implications of the used irrigation fluid.the investigators will further investigate the impact of intraoperative fluid management strategies on these Postoperative pulmonary complications and their effects on hemodynamics. By harnessing the potential of lung ultrasound in this context, we aspire to enhance both the diagnostic capabilities and overall safety of shoulder arthroscopic surgery, ultimately improving patient outcomes.

Shoulder arthroscopy, a minimally invasive surgical technique, has become a preferred method for addressing conditions like rotator cuff tears and recurrent joint instability due to its advantages, such as reduced post-operative pain and quicker rehabilitation. However, recent attention has shifted to potential complications, including issues related to irrigation fluid, patient positioning in the beach-chair posture, and anesthesia protocols. One key concern is the use of pressurized irrigation fluid, which, while essential for visualization, carries the risk of complications, including subcutaneous emphysema, pneumomediastinum, tension pneumothorax, air embolism, pulmonary edema, and atelectasis. These complications can have systemic effects, emphasizing the need for precise intraoperative fluid management.

Intraoperative fluid management strategies are a subject of continuous debate in the field of surgery, giving rise to three main strategies: 'liberal,' 'restricted,' and 'goal-directed' fluid therapy. These strategies vary in terms of the type of fluid used, timing of administration, and volume administered. While administering large volumes of fluids may improve organ perfusion, it may also increase the incidence of perioperative cardiopulmonary complications. Conversely, fluid restriction may reduce the length of hospital stay but increase the risk of postoperative acute kidney injury. Goal-directed therapy, which tailors fluid administration based on reproducible endpoints, has been associated with improved perioperative outcomes. The Bezold-Jarisch reflex is a cardiovascular reflex that can result in severe bradycardia and vasodilation when activated, especially in fasting patients with beach-chair position and other positions that lead to pooling of the blood in the lower limb and, in turn, lead to a decrease in venous return.

Understanding the intricate relationship between this reflex and intraoperative fluid management is paramount for improving patient safety and surgical outcomes. This reflex can be triggered by various factors, including rapid fluid administration and alterations in venous return, particularly in patients positioned in the beach chair posture.

Inclusion Criteria:

• Patients scheduled for elective shoulder arthroscopic surgery.
• Adults aged 18 years and above.
• Capable of providing informed consent voluntarily.
• No known allergies or sensitivities to substances commonly used in the surgical procedure or study.
• Stable baseline hemodynamics during preoperative evaluation

Exclusion Criteria:

• Patients scheduled for open shoulder surgery.

• Medical Comorbidities:

  • Pulmonary diseases, including chronic pulmonary diseases or pulmonary edema.
  • Previous cardiac diseases such as heart failure, myocardial infarction (MI), hypertension, and known types of arrhythmia.

• Severe Organ Disease: Severe liver or kidney disease.

• Body mass index (BMI) ≥ 35 kg/m².

• Abnormal coagulation function.

• Pregnancy

• Refusal to Participate or Patients who cannot provide informed consent due to cognitive impairment or other reasons.

• Previous shoulder arthroscopy.