Correlation of the "Preliminary Universal Surgical Invasiveness Score" (pUSIS) With Short Term Post-operative Clinical Outcome Parameters. An Observational Study

a number of 60 day-care as well as 100 in-hospital patients undergoing elective surgery in general anesthesia have been enrolled into this observational study. The recruitment of cases happened randomly on a daily basis according to the available operations in the surgical unit where the main investigator (NN) was performing her/his anesthesiological services. Thus there was no selection of specific surgeries or surgical disciplines.

Inclusion criteria: adult patients (>18 y) undergoing surgery in general anesthesia.

Exclusion criteria: emergency cases, patients aged \< 18 years, pregnant women, inability to give informed consent.

The data acquisition consisted of calculation of the individual pUSIS for the selected cases by end of surgery, and by collecting in the follow up period the following set of short term parameters:

In-hospital patients

• time duration from end of surgery till discharge from PACU
• time duration from end of surgery till discharge from IMCU
• time duration from end of surgery till discharge from ICU
• time duration from end of surgery till discharge from hospital up to 30 days
• Occurrence and severity of complications the during hospital stay or up to 30 days according to a predefined list

Day-care patients

• time duration from end of surgery till discharge from PACU
• time duration from end of surgery till discharge from hospital
• Occurrence and severity of complications the during hospital stay according to a predefined list
• Occurrence of readmission due to complications within a period of 10 days after surgery

The predefined list of complications that could be observed during the follow up period consists of:

• Occurrence of postoperative pain that needed medical intervention, duration of this state, average severity level (according an ordinal scale with the levels: mild, moderate, severe)
• Occurrence of hemodynamic instability, duration of this state, average severity level (according an ordinal scale with the levels: mild, moderate, severe)
• Occurrence of postoperative hemorrhage, quantification in total ml of estimated blood loss
• Occurrence of respiratory support, duration of this state
• Occurrence of thrombo-embolic complications
• Occurrence of hepato-renal complications
• Occurrence of cerebral/neurological complications
• Occurrence of infectiological/inflamatory complications
• Average level of self-assessed subjective wellbeing (according an ordinal scale with the levels: excellent, rather good, moderate, bad, extremely bad)

The obtained follow up results were subjected to correlation analyzis with the pUSIS values in order to determine their association and if possible to recognize threshold values that may indicate a suitable type/intensity of postoperative surveillance.