The Swedish Perioperative Register: Description, validation of data mapping and utility

Total intravenous or inhalational volatile anaesthesia and survival after colorectal cancer surgery: a Swedish national registry study

INTRODUCTION

Retrospective studies suggest that inhalational volatile anaesthetic agents may contribute to an increased risk of metastasis and reduction in survival rates when used during cancer surgery. This relationship may vary between cancer types due to different tumour biology and differences in surgical procedures. This study aimed to investigate the relationship between the type of anaesthetic used for maintenance of anaesthesia (propofol or inhalational volatile anaesthetic agent) and survival in patients with stage 1-3 colorectal cancer who underwent resection surgery under general anaesthesia in Sweden between 2014 and 2019.

METHODS

We identified patients from the Swedish Colorectal Cancer Registry. Their data, including cancer characteristics and adjuvant treatment, were then merged with information from the Swedish Peri-operative Registry. The primary outcome was overall survival, with disease-free survival as a secondary outcome.

RESULTS

Of the 11,598 patients included, 8161 had colon cancer and 3437 had rectal cancer. General anaesthesia was maintained with propofol in 2346 (20%) patients, while 9252 (80%) received an inhalational volatile anaesthetic agent. In the unmatched cohort, patients who had general anaesthesia maintained with propofol for colon cancer surgery showed improved survival compared with those receiving an inhalational volatile anaesthetic agent (hazard ratio 0.83, 95%CI 0.72-0.95, p = 0.008). After 1:2 propensity score matching, we observed no significant difference in survival rates in this group (hazard ratio 0.89, 95%CI 0.76-1.04, p = 0.127). In the rectal cancer group, there was no difference in survival in either the unmatched cohort (hazard ratio 0.83, 95%CI 0.65-1.08, p = 0.166) or after propensity score matching (hazard ratio 0.95, 95%CI 0.71-1.25, p = 0.702). There was no significant difference in disease-free survival in either type of cancer.

DISCUSSION

We found no association between the choice of agent for maintenance of anaesthesia and long-term survival outcomes in patients with colorectal cancer.

Effect of Plasma Air Purifiers on Infection Rates in Orthopedic Surgery

BACKGROUND

Surgical site infection (SSI) following orthopedic surgery impacts patient outcomes. Airborne transmission is one potential route of infection. Despite their high cost and resource demands, modern ventilation systems have shown limited efficacy in reducing SSI rates. This trial investigated the effectiveness of a low-cost air purifier in reducing SSI rates after orthopedic surgery.

METHODS

In a nationwide, multicenter, double-blind, cluster-randomized crossover, placebo-controlled superiority trial, we included all patients undergoing orthopedic surgery during the trial period. The intervention group underwent surgery in operating rooms with active Novaerus NV800 air purifiers, while the control group underwent surgery in operating rooms with the same air purifiers that were inactive. The primary end point was SSI within 12 weeks post surgery, defined as a postsurgery infection marker (PSIM), a custom composite outcome based on registry codes for prescribed antibiotics, diagnoses, and surgical procedures. Logistic regression was performed to evaluate the primary outcome.

RESULTS

Of the 40,547 patients analyzed, 19,869 were in the intervention group and 20,678 in the control group. The PSIM rate was 9.2% in the invention group, and 9.4% in the control group, with an odds ratio of 0.98 (95% confidence interval, 0.91 to 1.05) for the intervention group. This finding remained consistent across various subgroups based on diagnoses, hospital levels, and ventilation types.

CONCLUSIONS

In modern operating rooms equipped with standard, midrange airflow ventilation systems, the addition of wall-mounted plasma air purifiers did not reduce the PSIM rate after orthopedic surgery. (Funded by the Swedish Research Council; grant number, 2017-00198; ClinicalTrials.gov number, NCT02695368.).

Surgery in patients aged ≥ 80 years: mortality and recovery in a nationwide cohort study

INTRODUCTION

As the global population ages, the demand for surgical interventions in older adults is rising. Older patients face increased risks due to age-related physiological changes and comorbidities, making surgery and postoperative care challenging. This study aimed to assess short- and long-term mortality, as well as patient-centred outcomes such as days alive and at home 30 and 90 days after surgery, in patients aged ≥ 80 y undergoing surgical procedures.

METHODS

This nationwide cohort study utilised data from the Swedish Perioperative Register, including surgeries in patients aged ≥ 80 y in Sweden from January 2019 to March 2023. We linked peri-operative data with the National Patient Register for comorbidities and with the National Cause of Death Register. The primary outcome was all-cause 30-day mortality, with secondary outcomes of 365-day mortality and days alive and at home 30 and 90 days after surgery.

RESULTS

A total of 118,359 patients were included, with 54,320 undergoing elective and 64,039 acute surgeries. Thirty-day mortality was 1.2% for elective and 9.9% for acute surgeries. Mortality increased significantly with age, particularly for patients aged ≥ 90 y compared with those aged 80-84 y. Days alive and at home 30 and 90 days after surgery were significantly lower for acute surgery patients, indicating longer recovery times and more postoperative complications.

DISCUSSION

Older adults, especially those aged ≥ 90 y, experience high mortality and significant challenges in postoperative recovery after acute surgeries. Elective surgeries are associated with lower short-term mortality, suggesting that age alone should not preclude surgical interventions. Tailored peri-operative care and patient-centred decision-making are essential to improve outcomes in this vulnerable population.

Surgery for primary ventral hernias and risk of postoperative pain, nausea: a population-based register study

PURPOSE

The aim of this study was to evaluate risk factors for postoperative pain and nausea after open repair for primary ventral hernias.

METHOD

A population-based registry study was conducted based on data assembled from the Swedish national ventral hernia repair register between January 2016 and December 2021and cross-matched with the Swedish perioperative register.

RESULTS

Altogether 2064 open ventral hernia repairs were registered, including 816 (39.5%) performed on women. Of these, 91 (4.4%) were registered to suffer postoperative nausea or vomiting (PONV) and 403 (19.5%) postoperative pain (PP). In both univariable and multivariable logistic regression analyses, significant predictors of postoperative nausea and pain included male gender, which was associated with lower odds of both postoperative nausea (multivariable OR: 0.30, 95% CI: 0.18-0.49, P < 0.001) and postoperative pain (multivariable OR: 0.60, 95% CI: 0.44-0.83, P = 0.002). Additional predictors of postoperative nausea included emergency surgery (multivariable OR: 4.08, 95% CI: 1.10-15.08, P = 0.035), operative time > 40 min (multivariable OR: 4.15, 95% CI: 2.24-7.69, P < 0.001). Conversely total intravenous anesthesia was associated with lower incidence of PONV (multivariable OR: 0.40, 95% CI: 0.22-0.74, P = 0.003). Other factors, such as age, BMI, smoking status, ASA classification, hernia size, surgery type, operative time, and anesthesia type, were not significantly associated with postoperative pain after adjusting for other variables.

CONCLUSION

Postoperative nausea and vomiting (PONV) are significantly reduced with total intravenous anesthesia (TIVA) compared to inhalation anesthesia, with no notable difference in postoperative pain between the two methods.

Adherence to evidence-based guidelines for prevention of urinary retention in hip surgery patients: a multicentre observational study

Urinary retention is a healthcare complication putting patients at risk of unnecessary suffering and harm. Orthopaedic patients are known to face an increased such risk, calling for evidence-based preoperative assessment and corresponding measures to prevent bladder problems. The aim of this study was to evaluate healthcare professionals' adherence to risk assessment guidelines for urinary retention in hip surgery patients. This was an observational study from January 2021 to April 2021 with a descriptive and comparative design, triangulating three data sources: (I) Medical records for 1382 hip surgery patients across 17 hospitals in Sweden were reviewed for preoperative risk assessments for urinary retention and voiding-related variables at discharge; (II) The patients completed a survey regarding postoperative lower urinary tract symptoms, and; (III) data were extracted from a national quality registry regarding type of surgery, preoperative physical status, and perioperative urinary complications. Group differences were analysed with Chi-square/Fisher's exact test, t-test, Wilcoxon rank-sum test, or Mann-Whitney U-test. Logistic regression was used to analyse variables associated with completed risk assessments for urinary retention. Of all study participants, 23.4% (n = 323) had a preoperative documented risk assessment of urinary retention. Whether a risk assessment was performed was significantly associated with acute surgery [odds ratio (OR) 3.56, 95% confidence interval (CI) 2.48-5.12] and undergoing surgery at an academic hospital (OR 4.59, 95% CI 2.68-7.85). Acute patients were more often affected by urinary retention and had bladder issues and/or an indwelling catheter at discharge. More than every tenth patient (11. 9%, n = 53) completing the survey experienced intensified bladder problems after their hip surgery. The study shows a lack of adherence to risk assessment for urinary retention according to evidence-based guidelines, which negatively affects quality of care and patient safety.

Long-term Survival after Volatile or Propofol General Anesthesia for Bladder Cancer Surgery: A Retrospective National Registry Cohort Study

BACKGROUND

Prospective interventional trials and retrospective observational analyses provide conflicting evidence regarding the relationship between propofol versus inhaled volatile general anesthesia and long-term survival after cancer surgery. Specifically, bladder cancer surgery lacks prospective clinical trial evidence.

METHODS

Data on bladder cancer surgery performed under general anesthesia between 2014 and 2021 from the National Quality Registry for Urinary Tract and Bladder Cancer and the Swedish Perioperative Registry were record-linked. Overall survival was compared between patients receiving propofol or inhaled volatile for anesthesia maintenance. The minimum clinically important difference was defined as a 5-percentage point difference in 5-yr survival.

RESULTS

Of 7,571 subjects, 4,519 (59.7%) received an inhaled volatile anesthetic, and 3,052 (40.3%) received propofol for general anesthesia maintenance. The two groups were quite similar in most respects but differed in American Society of Anesthesiologists Physical Status and tumor stage. Propensity score matching was used to address treatment bias. Survival did not differ during follow-up (median, 45 months [interquartile range, 33 to 62 months]) in the full unmatched cohort nor after 1:1 propensity score matching (3,052 matched pairs). The Kaplan-Meier adjusted 5-yr survival rates in the matched cohort were 898 of 3,052, 67.5% (65.6 to 69.3%) for propofol and 852 of 3,052, 68.5% (66.7 to 70.4%) for inhaled volatile general anesthesia, respectively (hazard ratio, 1.05 [95% CI, 0.96 to 1.15]; P = 0.332). A sensitivity analysis restricted to 1,766 propensity score-matched pairs of patients who received only one general anesthetic during the study period did not demonstrate a difference in survival; Kaplan-Meier adjusted 5-yr survival rates were 521 of 1,766, 67.1% (64.7 to 69.7%) and 482 of 1,766, 68.9% (66.5 to 71.4%) for propofol and inhaled volatile general anesthesia, respectively (hazard ratio, 1.09 [95% CI, 0.97 to 1.23]; P = 0.139).

CONCLUSIONS

Among patients undergoing bladder cancer surgery under general anesthesia, there was no statistically significant difference in long-term overall survival associated with the choice of propofol or an inhaled volatile maintenance.

EDITOR’S PERSPECTIVE

Difference in early all-cause mortality among patients having hip arthroplasty a Swedish perioperative registry study 2013-2022

INTRODUCTION

Hip arthroplasty is a common orthopaedic procedure worldwide. There is an ongoing debate related to the fixation and anaesthesia impact on the 30-day mortality, particularly in the aging population with higher American Society of Anaesthesiology (ASA) Physical-Status.

AIM

To study the 30-day all-cause mortality in patients undergoing primary hip arthroplasty, with regards to the impact of age, ASA-class, anaesthesia techniques, indication for surgery and fixation techniques.

MATERIALS AND METHODS

Perioperative data for primary hip arthroplasty procedures for osteoarthritis and hip fractures registered in the Swedish Perioperative Registry (SPOR) between 2013 and June 2022 were collected. Binary logistic regressions were performed to assess the impact of age, ASA-class, anaesthetic technique, indication for surgery and fixation on odds ratio for 30-day mortality in Sweden.

RESULTS

In total, 79,114 patients, 49,565 with osteoarthritis and 29,549 with hip fractures were included in the main study cohort. Mortality was significantly higher among hip fracture patients compared with osteoarthritis, cumulative 8.2% versus 0.1% at 30-days respectively (p < 0.001). Age above 80 years (OR3.7), ASA 3-5 (OR3.3) and surgery for hip fracture (OR 21.5) were associated with significantly higher odds ratio, while hybrid fixation was associated with a significantly lower odds ratio (OR0.4) of 30-day mortality. In the same model, for the subgroups of osteoarthritis and hip fracture, only age (OR 3.7) and ASA-class (OR 3.3) had significant impact, increasing the odds ratio for 30-day mortality. Hemi arthroplasty was commonly used among the hip fracture patients 20.453 (69.2%), and associated with a significantly higher odds ratio for all-cause 30-day mortality as compared to total hip arthroplasty when adjusting for age and ASA-class and fixation 2.3 (95%CI 1.9-2.3, p < 0.001).

CONCLUSIONS

All-cause 30-day mortality associated with arthroplasty differed significantly between the two cohorts, hip fracture, and osteoarthritis (8.2% and 0.1% respectively) and mortality expectedly increased with age and higher ASA-class. Anaesthetic method and cement-fixation did not impact the odds ratio for all-cause 30-day mortality after adjustment for age and ASA-class.

Anaesthesia practice, quality indices including all-cause 30-day mortality associate to wrist fracture repositioning and surgery in Sweden: A perioperative register-based study 2018-2021

BACKGROUND

Wrist fracture is one of most common fractures frequently requiring surgical anaesthesia. There is limited information related to the anaesthetic practice and quality including 30-day mortality associated with wrist fracture in Sweden in recent years.

AIM

The aim of the present register-based study was to investigate the anaesthesia techniques used and quality indices including 30-day mortality associated with wrist fracture surgery in Sweden during the period 2018-2021.

MATERIALS AND METHODS

All fracture repositions, and surgical interventions related to wrist fracture requiring anaesthesia in patients aged >18 years registered in the Swedish Perioperative Register (SPOR) between 2018 and 2021 were included in the analysis. Information on age, ASA class, anaesthesia technique, severe operative events, most reported side-effects during recovery room stay and all-cause 30-day mortality was collected.

RESULTS

The data set included 25,147 procedures split into 14,796 females and 10,252 males (missing information n = 99) with a mean age of 52.9 ± 18.7 years and a significant age difference between females and males, 60.3 ± 15.4 and 42.2 ± 17.7 years, respectively. Mean age and ASA class increased during the study period (2018-2021), from 52.8 ± 18.6 to 54.0 ± 18.4 and ASA class 3-5 from 8.1% to 9.4% (p < .001 and p < .041, respectively). General anaesthesia (GA), GA combined with regional anaesthesia (RA), RA with or without sedation and sedation only was used in 41%, 13%, 40% and 6% of procedures, respectively, with minor changes over the study period. Pain at arrival in the recovery room (RR), (3.4%), severe pain during RR stay (2.1%), hypothermia (1.4%), postoperative nausea and vomiting (PONV) (1.2%) and urinary retention (0.5%) were the most reported side-effects during the RR stay. (RA) was associated with significantly lower occurrence of pain and PONV, and shorter RR stay, compared with GA (p < .001). The all-cause 30-day mortality was low (19 of 25,147 (0.08%)) with no differences over the period studied or anaesthetic technique.

CONCLUSION

General anaesthesia or general anaesthesia combined with regional anaesthesia are the most used anaesthetic techniques for wrist fracture procedures in Sweden. Recovery room pain, PONV, hypothermia and urinary retention is reported in overall low frequencies, with no change over the period studied, but in lower frequencies for regional anaesthesia. All-cause 30-day mortality was low; 0.08% with no change over time or between anaesthetic techniques. Thus, the present quality review based on SPOR data supports high quality of perioperative anaesthesia care.

Swedish registry study showed that 50% of paediatric operations were performed in university hospitals and mortality was low

AIM

To investigate the distribution of paediatric surgery in various hospitals and to study postoperative risk factors of mortality.

METHODS

Retrospective registry-based cohort study of children aged 0-14 years undergoing surgery from 2017 to 2021. Data were extracted from the Swedish Perioperative Registry. A mixed logistic regression was applied for the all-risk mortality analysis.

RESULTS

A total of 126 539 cases were identified, 50% in university, 36% in county and 14% in district hospitals. The dominating operations were appendectomy in 6667, orchidopexy in 5287, inguinal hernia repair in 4200 and gastrostomy in 1152 children. Among children under 1 year of age or American Society of Anesthesiologists Physical Status classification (ASA-PS-Class) 3-5, the majority underwent surgery in university hospitals. The 30-day mortality in university hospitals was 0.5% and in county hospitals 0%. The proportion of emergency surgery was similar in university and county hospitals. Independent risk factors of mortality were being under 1 year of age, ASA-PS-class 4-5, emergency surgery and surgery at university hospitals.

CONCLUSION

Half of all operations in children were performed in university hospitals, with low postoperative mortality despite effective centralisation of high risk patients <1 year of age or ASA-PS-Class 3-5.

Incidence and case ascertainment of treated in-hospital cardiac arrest events in a national quality registry - A comparison of reported and non-reported events

BACKGROUND

Approximately 2500 in-hospital cardiac arrest (IHCA) events are reported annually to the Swedish Registry of Cardiopulmonary Resuscitation (SRCR) with an estimated incidence of 1.7/1000 hospital admissions. The aim of this study was to evaluate the compliance in reporting IHCA events to the SRCR and to compare reported IHCA events with possible non-reported events, and to estimate IHCA incidence.

METHODS

Fifteen diagnose codes, eight Classification of Care Measure codes, and two perioperative complication codes were used to find all treated IHCAs in 2018-2019 at six hospitals of varying sizes and resources. All identified IHCA events were cross-checked against the SRCR using personal identity numbers. All non-reported IHCA events were retrospectively reported and compared with the prospectively reported events.

RESULTS

A total of 3638 hospital medical records were reviewed and 1109 IHCA events in 999 patients were identified, with 254 of the events not found in the SRCR. The case completeness was 77% (range 55-94%). IHCA incidence was 2.9/1000 hospital admissions and 12.4/1000 admissions to intensive care units. The retrospectively reported events were more often found on monitored wards, involved patients who were younger, had less comorbidity, were often found in shockable rhythm and more often achieved sustained spontaneous circulation, compared with in prospectively reported events.

CONCLUSION

IHCA case completeness in the SRCR was 77% and IHCA incidence was 2.9/1000 hospital admissions. The retrospectively reported IHCA events were found in monitored areas where the rapid response team was not alerted, which might have affected regular reporting procedures.

Big data in anaesthesia: a narrative, nonsystematic review

Data generation is growing with the use of 'anaesthesia information management systems' (AIMS), but the appropriate use of data for scientific purposes is often wasted by a lack of integration. This narrative review aims to describe the use of routinely collected data and its potential usefulness to improve the quality of care, first by defining the six levels of integration of electronic health records as proposed by the National Health Service (NHS) illustrated by examples in anaesthesia practice. Secondly, by explaining what measures can be taken to profit from those data on the micro-system level (for the patient), the meso-system (for the department and the hospital institution) and the macro-system (for healthcare and public health). We will next describe a homemade AIMS solution and the opportunities which result from his integration on the different levels and the research prospects implied. Opportunities outside of high-income countries will also be presented. All lead to the conclusion that a core dataset for peri-operative global research may facilitate a framework for the integration of large volumes of data from electronic health records. It will allow a constant re-evaluation of our practice as anaesthesiologists to offer the best care for patients. In this regard, the training of some anaesthesiologists in data science and artificial intelligence is of paramount importance. We must also take into account the ecological footprint of data centres as these are energy-consuming. It is essential to prepare for these changes and turn the speciality of anaesthesia, collaborating with data scientists, into a more prominent role of peri-operative medicine.

The effect of COVID-19 pandemic on perioperative factors: data from the Swedish Perioperative Register

BACKGROUND

The COVID-19 pandemic has affected healthcare organizations in many areas. The aim of this study was to describe surgical interventions, anesthesia, and postoperative outcomes in adult patients during the first wave and 1 year into the COVID-19 pandemic in Sweden, and to compare these outcomes with outcomes during the same period the year before the pandemic.

METHODS

Data were collected from the Swedish PeriOperative Register, and included 417, 233 perioperative registration of patients ≥ 18 years old between period 1 (March-June 2019), period 2 (March-June 2020), and period 3 (March-June 2021).

RESULTS

Compared with pre-pandemic (period 1), the number of surgical interventions decreased by 28% in the first wave (period 2); 1 year into the pandemic (period 3), the number of interventions was still 7.5% lower than pre-pandemic. The largest drops between periods 1 and 2 were noted in the specialties of ear, nose, and larynx surgery, - 55.6%; teeth, jaws, mouth, and pharynx surgery, - 45.0%; endocrine system surgery, - 38.8%. The number of acute surgeries remained stable during all three periods. Volatiles were more frequently used for the maintenance of general anesthesia in period 2 than in either period 1 or 3 (p < 0.001). Minor differences were noted throughout the periods in postoperative nausea and vomiting as well as postoperative pain.

CONCLUSIONS

The COVID-19 pandemic has had an impact on perioperative care in Sweden. During the first wave of the pandemic, the number of surgical interventions decreased, but the number of acute surgeries remained stable compared with pre-pandemic numbers. Perioperative organizations have had and will continue to have challenges handling the increased number of patients needing perioperative care.

The Nordic perioperative and intensive care registries-Collaboration and research possibilities

BACKGROUND

The Nordic perioperative and intensive care registries have been built up during the last 25 years to improve quality in intensive and perioperative care. We aimed to describe the Nordic perioperative and intensive care registries and to highlight possibilities and challenges in future research collaboration between these registries.

MATERIAL AND METHOD

We present an overview of the following Nordic registries: Swedish Perioperative Registry (SPOR), the Danish Anesthesia Database (DAD), the Finnish Perioperative Database (FIN-AN), the Icelandic Anesthesia Database (IS-AN), the Danish Intensive Care Database (DID), the Swedish Intensive Care Registry (SIR), the Finnish Intensive Care Consortium, the Norwegian Intensive Care and Pandemic Registry (NIPaR), and the Icelandic Intensive Care Registry (IS-ICU).

RESULTS

Health care systems and patient populations are similar in the Nordic countries. Despite certain differences in data structure and clinical variables, the perioperative and intensive care registries have enough in common to enable research collaboration. In the future, even a common Nordic registry could be possible.

CONCLUSION

Collaboration between the Nordic perioperative and intensive care registries is both possible and likely to produce research of high quality. Research collaboration between registries may have several add-on effects and stimulate international standardization regarding definitions, scoring systems, and benchmarks, thereby improving overall quality of care.