Introduction
Intraoperative adverse events (IAE) during surgery can lead to increased mortality,
morbidity, and prolonged hospital stays. However, they are often underreported due to a
lack of standardised classification systems, particularly in major gynaecological surgery. To address this gap, colleagues from the QLD Centre for Gynaecological Cancer developed a new Classification system of intraoperative Adverse Surgical Events (CiASE) that is based on the severity and impact on patient recovery.
Methods
Expert gynaecological surgeons from 3 countries participated in developing and validating the CiASE. A workshop was conducted to create a grading system, followed by testing and refinement. Case vignettes were generated from real surgical cases for validation. Surgeons applied CiASE to these vignettes, and inter-rater reliability was assessed. Statistical analysis included calculation of accuracy, sensitivity, specificity, and Krippendorff's Alpha coefficient.
Results
Twenty-five surgeons participated in the validation process. The cohort demonstrated high accuracy in grading IAE’s, with 95.2% agreement overall. The system showed good sensitivity and specificity across all grades. Inter-rater reliability was almost perfect (α=0.95), indicating strong agreement among surgeons.
Meaning
CiASE provides a standardized method for classifying intraoperative adverse events in
gynaecological surgery, considering both severity and impact on patient outcomes. It
addresses the underreporting of IAE’s. Future research will focus on evaluating clinical
outcomes.
How to apply CiASE
The CiASE only applies to AE’s recognised intraoperatively. An AE diagnosed postoperatively that would have logically occurred intraoperatively (but was not recognised) is not regarded as an intraoperative complication and the CiASE will not be applied. The intraoperative AE is assigned intraoperatively but it’s severity can be changed up to 6 weeks post operatively.
Grade 0 – The absence of an intraoperative AE
Examples:
Routine procedure as planned
Conversion from minimally invasive surgery to laparotomy in the absence of an AE such as laparotomy for specimen retrieval or adhesions unable to be managed laparoscopically, irrespective of extended LOS.
Serosal tear (when mucosa of viscus is not breached)
Grade 1 - Minimal: Intraoperative surgical AE with no or minimal impact on post operative course or patient outcome (does not prolong LOS).
Examples:
Enterotomy (requires breach of mucosa) managed by oversew or bowel resection.
Cone bx and intraoperative opening of POD
Blood loss requiring transfusion without prolonging LOS
Splenic tear without significant consequence
Uterine perforation without other adverse event
Grade 2 – Moderate: Intraoperative surgical AE impacting on planned postoperative course or outcome for less than 6 weeks.
Examples:
Any intraoperative surgical AE requiring conversion from minimally invasive surgery to laparotomy (e.g. bleeding or viscus injury). Note: Conversion from minimally invasive surgery to open without a surgical AE does not meet criteria for inclusion
Any intraoperative surgical AE associated with prolonged length of stay and/or necessitating ICU admission (e.g. CO2 embolus)
Blood loss requiring transfusion prolonging LOS
Nerve injury requiring medication and or physiotherapy (self-limiting) for 6 weeks
Urological injury requiring repair and or stenting with planned delayed cystogram
and or delayed IDC/stent removal
Intraoperative rupture of adnexa or uterus – requiring adjuvant treatment that would have otherwise not been required
Grade 3 - Severe: Intraoperative surgical AE, requiring subsequent unplanned readmission and/or return to operating theatre and/or intervention radiology OR continued or expected disability as a consequence of treatment beyond 6 weeks from discharge from hospital
Examples:
Intraoperative AE requiring diversion of bowel (stoma)
Nerve injury (long-term) requiring rehab for 6 weeks
Any AE requiring associated treatment for longer than 6 weeks
Splenic injury requiring splenectomy and associated long-term medical treatments
Uterine perforation requiring adjuvant treatment as a consequence of the injury
(and would not have needed adjuvant treatment in the absence of the event)
Grade 4 – Death: Intraoperative or peri-operatively of any cause