Our goal is to conduct a prospective, national, randomized-controlled, multicenter trial to investigate the effect of handover of anesthesia care on the occurrence of adverse outcomes in the perioperative period.

Intraoperative handover of anesthesia care frequently occurs in clinical routine. Communication between the two anesthesiologists plays a pivotal role for the continuation of anesthesia care. The outgoing clinician must inform the incoming clinician in a short period of time about the important pre- and intraoperative facts and about the surgery while continuing to provide patient care. Contributing factors to inadequate communication during handoffs include insufficient or misleading information, busy and distractive environment, ineffective communication methods, lack of time, lack of standardized procedures, and insufficient staffing. It is estimated that the majority of adverse events in health care involve miscommunication during the handoff between physicians and perhaps other health care practitioners (https://www.jointcommission.org/hot\_topics\_toc/).

The goal is to conduct a prospective, national, randomized-controlled, multicenter trial to investigate the effect of handover of anesthesia care on the occurrence of adverse outcomes in the perioperative period. The investigators hypothesizes that handover of anesthesia care does increase the risk for adverse outcomes. The primary outcome parameter is a combined endpoint consisting of all-cause mortality, readmission to any hospital, or major postoperative complications (including prolonged postoperative ventilation ≥ 48 h, major disruption of surgical wound, bleeding, pneumonia, atrial fibrillation, moderate or severe acute kidney injury, new onset of hemodialysis, cardiac arrest, myocardial infarction, sepsis, stroke, pulmonary embolism, deep venous thrombosis, shock, unplanned return to operating room) within 30 days of index surgery. Secondary endpoints are the individual criteria of the primary endpoint, hospital length of stay, ICU admission, and ICU length of stay. As the currently available data on handover of anesthesia care have not been obtained from prospective, randomized controlled trials, the results of the Handicap trial will bring new insights to anesthesia care to improve patients' outcome.

Inclusion Criteria:

• Age >= 18 years
• Major surgeries with a duration of at least 2 h (requirement of postoperative admission to hospital for at least 1 night)
• ASA 3-4
• Informed consent

Exclusion Criteria:

• Previous surgery within the same surgical subgroup within the last 6 months
• Pregnancy, breastfeeding
• Patients participating in another interventional trial within the last 3 months
• Persons with any kind of dependency on the investigator or employed by the investigator