The number of comorbidities as an important cofactor to ASA class in predicting postoperative outcome: An international multicentre cohort study.

BACKGROUND: Multimorbidity is a growing burden in our ageing society and is associated with perioperative morbidity and mortality. Despite several modifications to the ASA physical status classification, multimorbidity as such is still not considered. Thus, the aim of this study was to quantify the burden of comorbidities in perioperative patients and to assess, independent of ASA class, its potential influence on perioperative outcome. METHODS: In a subpopulation of the prospective ClassIntra® validation study from eight international centres, type and severity of anaesthesia-relevant comorbidities were additionally extracted from electronic medical records for the current study. Patients from the validation study were of all ages, undergoing any type of in-hospital surgery and were followed up until 30 days postoperatively to assess perioperative outcomes. Primary endpoint was the number of comorbidities across ASA classes. The associated postoperative length of hospital stay (pLOS) and Comprehensive Complication Index (CCI®) were secondary endpoints. On a scale from 0 (no complication) to 100 (death) the CCI® measures the severity of postoperative morbidity as a weighted sum of all postoperative complications. RESULTS: Of 1421 enrolled patients, the mean number of comorbidities significantly increased from 1.5 in ASA I (95% CI, 1.1-1.9) to 10.5 in ASA IV (95% CI, 8.3-12.7) patients. Furthermore, independent of ASA class, postoperative complications measured by the CCI® increased per each comorbidity by 0.81 (95% CI, 0.40-1.23) and so did pLOS (geometric mean ratio, 1.03; 95% CI, 1.01-1.06). CONCLUSIONS: These data quantify the high prevalence of multimorbidity in the surgical population and show that the number of comorbidities is predictive of negative postoperative outcomes, independent of ASA class.

Clinical adhesion score (CLAS): development of a novel clinical score for adhesion-related complications in abdominal and pelvic surgery.

BACKGROUND: Adhesions are a major cause of long-term postsurgical complications in abdominal and pelvic surgery. Existing adhesion scores primarily measure morphological characteristics of adhesions that do not necessarily correlate with morbidity. The aim of this study was to develop a clinical adhesion score (CLAS) measuring overall clinical morbidity of adhesion-related complications in abdominal and pelvic surgery. METHODS: An international Delphi study was performed to identify relevant score items for adhesion-related complications, including small bowel obstruction, female infertility, chronic abdominal or pelvic pain, and difficulties at reoperation. The CLAS includes clinical outcomes, related to morbidity of adhesions, and weight factors, to correct the outcome scores for the likelihood that symptoms are truly caused by adhesions. In a pilot study, two independent researchers retrospectively scored the CLAS in 51 patients to evaluate inter-observer reliability, by calculating the Intraclass correlation coefficient. During a feasibility assessment, we evaluated whether the CLAS completely covered different clinical scenarios of adhesion-related morbidity. RESULTS: Three Delphi rounds were performed. 43 experts agreed to participate, 38(88%) completed the first round, and 32 (74%) the third round. Consensus was reached on 83.4% of items. Inter-observer reliability for the CLAS was 0.95 (95% CI 0.91-0.97). During feasibility assessment, six items were included. As a result, the CLAS includes 22 outcomes and 23 weight factors. CONCLUSION: The CLAS represents a promising scoring system to measure and monitor the clinical morbidity of adhesion-related complications. Further studies are needed to confirm its utility in clinical practice.

Appraisal of Intraoperative Adverse Events to Improve Postoperative Care.

BACKGROUND: Intraoperative adverse events (iAEs) are associated with adverse postoperative outcomes and cause a significant healthcare burden. However, a critical appraisal of iAEs is lacking. Considering the details of iAEs could benefit postoperative care. We comprehensively analyzed iAEs in a large series including all types of operations and their relation to postoperative complications. METHODS: All patients enrolled in the multicenter ClassIntra® validation study (NCT03009929) were included in this analysis. The surgical and anesthesia team prospectively recorded all iAEs. Two researchers, blinded to each other's ratings, appraised all recorded iAEs according to their origin into four categories: surgery, anesthesia, organization, or other, including subcategories such as organ injury, arrhythmia, or instrument failure. They further descriptively analyzed subcategories of all iAEs. Postoperative complications were assessed using the Comprehensive Complication Index (CCI®), a weighted sum of all postoperative complications according to the Clavien-Dindo classification. The association of iAE origins in addition to the severity grade of ClassIntra® on CCI® was assessed with a multivariable mixed-effects generalized linear regression analysis. RESULTS: Of 2520 included patients, 778 iAEs were recorded in 610 patients. The origin was surgical in 420 (54%), anesthesia in 283 (36%), organizational in 34 (4%), and other in 41 (5%) events. Bleeding (n = 217, 28%), hypotension (n = 118, 15%), and organ injury (n = 98, 13%) were the three most frequent subcategories in surgery and anesthesia, respectively. In the multivariable mixed-effect analysis, no significant association between the origin and CCI® was observed. CONCLUSION: Analyzing the type and origin of an iAE offers individualized and contextualized information. This detailed descriptive information can be used for targeted surveillance of intra- and postoperative care, even though the overall predictive value for postoperative events was not improved by adding the origin in addition to the severity grade.

Classification of intraoperative adverse events in visceral surgery.

BACKGROUND: Intraoperative adverse events (iAEs) are frequent in visceral surgery, but severity and related postoperative outcome are poorly investigated. A novel classification of intraoperative adverse events, ClassIntra, includes surgical and anesthesiologic intraoperative adverse events using 5 severity grades and showed a high criterion and construct validity across all surgical disciplines. ClassIntra was studied for reproducibility in a prespecified group of patients undergoing visceral surgery. METHODS: iAEs were recorded in all patients enrolled in the ClassIntra validation study (NCT03009929). Postoperative complications were assessed daily according to the Clavien-Dindo classification. Results of the visceral group were compared with those of the non-visceral group and the full cohort. The risk-adjusted association between most severe intra and postoperative complications was investigated in a multivariable proportional odds model. Second, risk-adjusted association between ClassIntra grade and Comprehensive Complication Index, and postoperative length of stay was investigated. RESULTS: In total, 1,270 out of 2,520 patients (50%) underwent visceral surgery. Compared with the nonvisceral group and full cohort, more intraoperative (337/1270 [27%] vs 273/1250 [22%] vs 610/2520 [24%] patients) and postoperative complications (457/1270 [36%] vs 381/1250 [30%] vs 838/2520 [33%] patients) occurred. The risk for a more severe postoperative complication increased with each ClassIntra grade (odds ratio [95% confidence interval] I vs 0 1.10 [0.73 to 1.66], II vs 0 1.69 [1.10 to 2.60], III vs 0 2.31 [1.21 to 4.41], IV vs 0 2.35 [0.69 to 8.06]). Accordingly, CCI and postoperative length of stay increased with each ClassIntra grade in the visceral group, comparable with the nonvisceral and full cohort. CONCLUSION: Consistent results for the association of intraoperative adverse events and patient outcomes render ClassIntra a valuable instrument in visceral surgery.

Prospective validation of classification of intraoperative adverse events (ClassIntra): international, multicentre cohort study.

OBJECTIVE: To prospectively assess the construct and criterion validity of ClassIntra version 1.0, a newly developed classification for assessing intraoperative adverse events. DESIGN: International, multicentre cohort study. SETTING: 18 secondary and tertiary centres from 12 countries in Europe, Oceania, and North America. PARTICIPANTS: The cohort study included a representative sample of 2520 patients in hospital having any type of surgery, followed up until discharge. A follow-up to assess mortality at 30 days was performed in 2372 patients (94%). A survey was sent to a representative sample of 163 surgeons and anaesthetists from participating centres. MAIN OUTCOME MEASURES: Intraoperative complications were assessed according to ClassIntra. Postoperative complications were assessed daily until discharge from hospital with the Clavien-Dindo classification. The primary endpoint was construct validity by investigating the risk adjusted association between the most severe intraoperative and postoperative complications, measured in a multivariable hierarchical proportional odds model. For criterion validity, inter-rater reliability was evaluated in a survey of 10 fictitious case scenarios describing intraoperative complications. RESULTS: Of 2520 patients enrolled, 610 (24%) experienced at least one intraoperative adverse event and 838 (33%) at least one postoperative complication. Multivariable analysis showed a gradual increase in risk for a more severe postoperative complication with increasing grade of ClassIntra: ClassIntra grade I versus grade 0, odds ratio 0.99 (95% confidence interval 0.69 to 1.42); grade II versus grade 0, 1.39 (0.97 to 2.00); grade III versus grade 0, 2.62 (1.31 to 5.26); and grade IV versus grade 0, 3.81 (1.19 to 12.2). ClassIntra showed high criterion validity with an intraclass correlation coefficient of 0.76 (95% confidence interval 0.59 to 0.91) in the survey (response rate 83%). CONCLUSIONS: ClassIntra is the first prospectively validated classification for assessing intraoperative adverse events in a standardised way, linking them to postoperative complications with the well established Clavien-Dindo classification. ClassIntra can be incorporated into routine practice in perioperative surgical safety checklists, or used as a monitoring and outcome reporting tool for different surgical disciplines. Future studies should investigate whether the tool is useful to stratify patients to the appropriate postoperative care, to enhance the quality of surgical interventions, and to improve long term outcomes of surgical patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT03009929.