Minimally invasive approaches, facilitated with advanced technology such as augmented reality, mixed reality, and robotics, as well as artificial intelligence (AI), novel imaging, innovative navigation systems, and 3D printing, will extend the capabilities of surgeons and proceduralists. Next-generation surgical robotics will be more versatile, portable, and cheaper, as well as more autonomous. A novel robot that allows insertion of two robotic arms and a camera through a 1.5 cm incision is being evaluated. Advanced visualization capabilities and AI-supported ultra-precise 3D images will replace large, heavy microscopes with wearable mixed-reality devices (i.e., devices that merge augmented reality and virtual reality). Non-robotics for diagnosis and drug delivery may become a reality. These innovative technological platforms should improve procedural precision, safety, and efficiency, as well as lead to development of innovative procedures. Furthermore, these technological advances should reduce variability in surgical performance, decrease surgical stress response, reduce periprocedure complications, and allow rapid recovery. Consequently, there will be growth in the procedures performed outside the OR and freestanding ambulatory surgery centers (ASCs) (Anesth Analg 2020;131:695-8; Anesth Analg 2021;133:1387-90).

Implementation of enhanced recovery after surgery (ERAS) protocols that shorten hospital length of stay has further facilitated the migration of surgical procedures from the inpatient to the outpatient setting (Anesth Analg 2019;128:5-7; Best Pract Res Clin Anaesthesiol 2021;35:479-89; Curr Opin Anaesthesiol 2020;33:711-7). Also, the COVID-19 pandemic that overwhelmed hospitals forced migration of some essential (urgent and emergent) surgical procedures to freestanding ASCs (Anesth Analg 2020;131:31-6). Importantly, the high efficiency and productivity of ASCs combined with improved outcomes compared to the inpatient setting explains the expansion of ambulatory surgery in this era of value-based purchasing (Curr Opin Anaesthesiol 2008;21:695-8; Anesth Analg 2021;133:1402-5; Ann Surg 2021;273:909-16; Anesth Analg 2021;132:1215-22). ASCs provide more personal and intimate care, with emphasis on patient-related outcomes (Curr Opin Anaesthesiol 2021;34:667-71). Also, avoidance of hospitalization prevents hospital-associated complications (e.g., sleep deprivation, immobilization, nosocomial infections, and medication errors). This allows us to achieve the triple aim of health care – patient satisfaction, population health, and value (Health Aff [Millwood] 2008;27:759-69).

Application of ERAS principles is crucial for safe and efficient ambulatory care (Curr Opin Anaesthesiol 2020;33:711-7). Appropriate procedure-specific patient selection can influence patient safety and outcomes and thus is key to success of ambulatory care (Anesth Analg 2021;133:1415-30; Anesth Analg 2021;133:1431-6). In addition, preoperative identification and optimization of comorbid conditions would further improve patient safety and perioperative outcomes. Preoperative patient education and engagement are critical and can be improved using new technologies and tools (e.g., telemedicine) (Curr Opin Anaesthesiol 2021;34:672-7). Patients should receive specific instructions regarding perioperative care, including minimization of duration of fasting while encouraging hydration during the fasting period (Anesth Analg 2019;128:5-7). Patients and their caregivers must have realistic expectations regarding post-discharge care. They should understand that they must be active participants in their postoperative care and rehabilitation process and thus should be prepared to assume this responsibility (Curr Opin Anaesthesiol 2021;34:667-71).

Regional anesthesia and sedation-analgesia are preferred as they facilitate recovery and because residual effects of drugs used to provide general anesthesia (i.e., hypnotic-sedatives, neuromuscular blocking agents, and opioids) can influence postoperative recovery and complications (Anesth Analg 2019;128:5-7). However, neuraxial anesthesia (i.e., spinal anesthesia) can delay recovery and discharge home (Curr Opin Anaesthesiol 2020;33:746-52). An optimal general anesthetic technique would include a minimal number of short-acting drug combinations administered at the lowest possible doses (Best Pract Res Clin Anaesthesiol 2021;35:531-41; Anesth Analg 2020;131:738-40; Best Pract Res Clin Anaesthesiol 2019;33:341-51; Anesthesiology 2021;134:645-59). In addition, opioid-sparing multimodal analgesic techniques should include acetaminophen combined with non-steroidal anti-inflammatory drugs (NSAIDs) or cyclooxygenase (COX-2)-specific inhibitors administered either preoperatively or intraoperatively and continued postoperatively (Best Pract Res Clin Anaesthesiol 2019;33:259-67). Regional analgesic techniques (e.g., peripheral nerve blocks, interfascial plane blocks, or surgical site infiltration) should also be administered (Best Pract Res Clin Anaesthesiol 2019;33:303-15; Best Pract Res Clin Anaesthesiol 2019;33:317-24). Furthermore, all patients should receive prophylaxis with at least two antiemetics (typically dexamethasone 8 mg, ondansetron 4 mg) irrespective of their risk status. High-risk populations (patients with a history of motion sickness, history of previous PONV, high opioid requirements after surgery) should receive three to four antiemetics (Curr Opin Anaesthesiol 2021;34:695-702).

After the procedure, there is emphasis on discharge home (rather than extended care facilities) because it is associated with cost savings (Anesth Analg 2021;133:1375-8). One of the concerns of ambulatory surgery is the potential for delayed diagnosis and management of potential complications (Anesth Analg 2020;131:494-6; Best Pract Res Clin Anaesthesiol 2021;35:575-89). Therefore, it is imperative to measure outcomes by implementing a comprehensive, continuous quality improvement program using appropriate metrics (e.g., adherence to guidelines, perioperative morbidity and mortality, duration of stay in the ambulatory facility, unplanned hospital transfers, and acute care visits and hospital readmission after discharge home as well as patient-reported outcomes).

With the world of health care becoming global, it is necessary to promote high-quality and safe ambulatory surgery and non-operating room procedures worldwide. This goal is achieved through education and training for surgeons, anesthesiologists, and nurses practicing in the ambulatory setting as well as education for patients. The International Association for Ambulatory Surgery (IAAS), a conglomerate of ambulatory surgery associations from numerous countries (, facilitates worldwide, multidisciplinary international exchange of knowledge and experience in ambulatory surgery. With the depth and breadth of United States-based experience, the Society for Ambulatory Anesthesia (SAMBA), one of the founding members of IAAS, and ASA can influence international ambulatory surgical practice.

In summary, freestanding ASCs and hospital-based outpatient non-operating room settings will continue to evolve. This places the burden on anesthesiologists to provide safe, high-quality, efficient, and cost-effective care in these challenging settings. Expansion of extensive procedures in medically complex patients to the ambulatory setting will require additional resources such as personnel, advanced equipment, and ancillary services like laboratory, blood bank, and respiratory therapy. Delivery of patient-centered care will require modification of the current approach to perioperative care. Furthermore, future payment models will need to be modified to reflect the increased burden on outpatient settings. Finally, it is necessary to eliminate health care inequalities in the use of freestanding ASCs (JAMA Surg 2020;155:1123-31).