Implementation and validation of a novel instrument for the grading of unexpected events in paediatric surgery: Clavien–Madadi classification

Background: Inconsistent definitions of complications and unexpected events have limited accurate analysis of surgical outcomes. Perioperative outcome classifications currently used for adult patients have limitations when used for children./ Methods: A multidisciplinary group of experts modified the Clavien–Dindo classification to increase its utility and accuracy in paediatric surgery cohorts. Organizational and management errors were considered in the novel Clavien–Madadi classification, which focuses on procedural invasiveness rather than anaesthetic management. Unexpected events were prospectively documented in a paediatric surgery cohort. Results of the Clavien–Dindo and Clavien–Madadi classifications were compared and correlated with procedure complexity./ Results: Unexpected events were prospectively documented in a cohort of 17 502 children undergoing surgery between 2017 and 2021. The results of both classifications were highly correlated (ρ = 0.95), although the novel Clavien–Madadi classification identified 449 additional events (organizational and management errors) over the Clavien–Dindo classification, increasing the total number of events by 38 per cent (1605 versus 1158 events). The results of the novel system correlated significantly with the complexity of procedures in children (ρ = 0.756). Furthermore, grading of events > grade III according to the Clavien–Madadi classification showed a higher correlation with procedure complexity (ρ = 0.658) than the Clavien–Dindo classification (ρ = 0.198)./ Conclusion: The Clavien–Madadi classification is a tool for the detection of surgical and non-medical errors in paediatric surgery populations. Further validation in paediatric surgery populations is required before widespread use

Effect of acute kidney injury requiring extended dialysis on 28 day and 1 year survival of patients undergoing interventional lung assist membrane ventilator treatment

<p>Abstract</p> <p>Background</p> <p>Extracorporeal lung assist devices are increasingly used in the intensive care unit setting to improve extracorporeal gas exchange mainly in patients with acute respiratory distress syndrome. ARDS is frequently accompanied by acute kidney injury; however it is so far unknown how the combination of these two conditions affects long term survival of critically ill patients.</p> <p>Methods</p> <p>In a retrospective analysis of a tertiary care hospital we evaluated all patients undergoing interventional lung assist (iLA) treatment between January 1^st2005 and December 31^st2009. Data from all 61 patients (31 F/30 M), median age 40 (28 to 52) years were obtained by chart review. Follow up data up to one year were obtained.</p> <p>Results</p> <p>Of the 61 patients undergoing iLA membrane ventilator treatment 21 patients had acute kidney injury network (AKIN) stage 3 and were treated by extended dialysis (ED). Twenty-eight day survival of all patients was 33%. While patients without ED showed a 28 day survival of 40%, the survival of patients with ED was only 19%. Patients on ED were not different in respect to age, weight, Horowitz index and underlying disease.</p> <p>Conclusions</p> <p>AKI requiring ED therapy in patients undergoing iLA treatment increases mortality in ICU patients. Patients in whom iLA was placed as a bridge to lung transplantation and that were successfully transplanted showed the best outcome. Future studies have to clarify whether it is possible to identify patients that truly benefit from the combination of these two extracorporeal treatment methods.</p

Implementation and validation of a novel instrument for the grading of unexpected events in paediatric surgery : Clavien-Madadi classification

Background Inconsistent definitions of complications and unexpected events have limited accurate analysis of surgical outcomes. Perioperative outcome classifications currently used for adult patients have limitations when used for children. Methods A multidisciplinary group of experts modified the Clavien-Dindo classification to increase its utility and accuracy in paediatric surgery cohorts. Organizational and management errors were considered in the novel Clavien-Madadi classification, which focuses on procedural invasiveness rather than anaesthetic management. Unexpected events were prospectively documented in a paediatric surgery cohort. Results of the Clavien-Dindo and Clavien-Madadi classifications were compared and correlated with procedure complexity. Results Unexpected events were prospectively documented in a cohort of 17 502 children undergoing surgery between 2017 and 2021. The results of both classifications were highly correlated (rho = 0.95), although the novel Clavien-Madadi classification identified 449 additional events (organizational and management errors) over the Clavien-Dindo classification, increasing the total number of events by 38 per cent (1605 versus 1158 events). The results of the novel system correlated significantly with the complexity of procedures in children (rho = 0.756). Furthermore, grading of events > grade III according to the Clavien-Madadi classification showed a higher correlation with procedure complexity (rho = 0.658) than the Clavien-Dindo classification (rho = 0.198). Conclusion The Clavien-Madadi classification is a tool for the detection of surgical and non-medical errors in paediatric surgery populations. Further validation in paediatric surgery populations is required before widespread use.The authors report a novel instrument for the grading of unexpected events in paediatric surgery by a multidisciplinary expert group, and based on the Clavien-Dindo classification. The Clavien-Madadi classification was tested and validated in a cohort of 17 502 children and proved to be a valuable instrument in daily paediatric surgical practice.Peer reviewe

Mean nickel levels in urine following MIRPE.

Mean nickel concentrations in urine (stainless steel group in black, TiN coated bar group in grey), error bars show standard error of the mean. Hatched area indicates values below the reference values. The postoperative concentrations in the TiN coated bar group were compared to preoperative values; the overall difference was statistically significant (p = 0.0038). Additionally, values at each time point were compared to the corresponding time point of stainless steel bars (*p<0.05; **p<0.01). Postop = postoperative, TiN = titanium-nitride, MIRPE = minimally-invasive repair of pectus excavatum.</p

Nickel and chromium levels in local tissue before MIRPE and at time of bar removal.

Mean concentrations of nickel and chromium in tissue (stainless steel group in black, TiN coated bar group in grey), error bars show standard error of the mean. Values at bar removal were compared to stainless steel bars (*p<0.05). Postop = postoperative, TiN = titanium-nitride, MIRPE = minimally-invasive repair of pectus excavatum.</p

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IntroductionPrevious studies demonstrated a release of toxic metals, e.g. nickel and chromium, from stainless steel bars used for minimally invasive repair of pectus excavatum (MIRPE). In the present study, we investigated the impact of titanium nitride coating on the metal release and exposure of MIRPE patients.Material and methodsWe analyzed the courses of nickel and chromium levels in blood, urine and local tissue in patients undergoing MIRPE with a titanium nitride coated pectus bar between 03/2017 and 10/2018. Sample collection was scheduled prior to MIRPE, at defined postoperative time points and at bar removal. Additionally, we evaluated irritative symptoms. Results were compared to a control group who received uncoated stainless steel bars in a previous time period (03/2015–02/2017).Results12 patients received coated pectus bars (mean age 15.7 years). The control group included 28 patients. After implantation of a titanium nitride coated bar, significant increase in systemic nickel and chromium levels after one, two and three years was noted. In an interim analysis one year after MIRPE, we observed patients with coated bars to have significantly elevated trace metal values compared to the control group. This elevation persisted throughout the observation period. Tissue metal values were also significantly increased. Irritative symptoms occurred significantly more often in study patients compared to controls (50.0% vs. 14.3%).ConclusionsCoating of pectus bars with titanium nitride failed to reduce metal contamination after MIRPE. Instead, it resulted in a significant increase of trace metal levels after MIRPE, compared to patients with stainless steel bars, which may be explained by wear of the coating and inter-component mobilization processes.</div

Mean chromium levels in urine following MIRPE.

Mean chromium concentrations in urine (stainless steel group in black, TiN coated bar group in grey), error bars show standard error of the mean. Hatched area indicates values below the reference values. The postoperative concentrations in the TiN coated bar group were compared to preoperative values; the overall difference was statistically significant (p.001). Additionally, values at each time point were compared to the corresponding time point of stainless steel bars (*p<0.05; **p<0.01; ***p<0.001). Postop = postoperative, TiN = titanium-nitride, MIRPE = minimally-invasive repair of pectus excavatum.</p

Mean and median metal levels at standard time points.

Mean and median metal levels at standard time points.</p

Explanted TiN coated stabilizers.

Parts of the golden TiN coating are rubbed off at the region of contact surface with the bar, uncovering the underlying stainless steel (arrowheads). TiN = titanium-nitride.</p