Platform trials for anaesthesia and perioperative medicine: a narrative review

Shaping the Future of Cardiac Anesthesia: Emerging Trends and Research Directions

This article provides an overview of knowledge gaps that need to be addressed in perioperative cardiac surgery, including concomitant surgical procedures, approaches to the conduct of cardiopulmonary bypass, precision medicine, and patient-important recovery outcomes. In addition, emerging approaches to research conduct are discussed, including the use of new analytical techniques involving artificial intelligence and platform trials.

PErioperative respiratory care aNd outcomes for patients underGoing hIgh risk abdomiNal surgery (PENGUIN): a randomised international internal pilot trial

Background

Infections are a common complication of abdominal surgery in low- and middle-income countries (LMICs). The role of a high fraction of inspired oxygen (FiO2) and chlorhexidine mouthwash in preventing post-operative infections is unconfirmed.

Methods

Internal pilot phase of an international outcome assessor-blinded, 2x2 factorial randomised trial of patients aged ≥10-years undergoing midline laparotomy in LMIC hospitals. The main trial objectives are to compare the clinical effectiveness of preoperative 0.2% chlorhexidine mouthwash in preventing pneumonia versus no mouthwash, and 80-100% perioperative FiO2 to prevent surgical site infection (SSI) versus 21-35% FiO2. This 12-month internal pilot assessed feasibility of hospital site opening, patient recruitment, intervention adherence, patient follow-up and safety. Patients were randomised in a 1:1:1:1 ratio to the four intervention group combinations and followed up for 30 days.

Results

We recruited 927 patients from seven hospitals in India and South Africa over 12 months from November 2020. There were 907 adults (97.8%) and 20 children aged ten or over (2.2%): 89/927 (9.6%) patients died. Site opening reached 70% of our target (7/10) hospitals, and patient recruitment 107% (927/870). 917/927 (99%) patients in the mouthwash arm, and 840/927 (91%) patients in the oxygen arm received the allocated intervention. Lower adherence to the oxygen intervention related mainly to clinically necessary FiO2 increases in the 21-35% FiO2 arm. 30-day follow-up was completed appropriately for 924/927 (99%) patients. and was performed by a masked assessor for all patients. There were no reported safety events.

Conclusion

This pilot showed the feasibility and safety of a major phase III trial in post-operative infection prevention in LMICs.

Trial registration

ClinicalTrials.gov NCT04256798.

Systematic Review of Surgical Site Infection Prevention Guideline Recommendations for Maintenance of Homeostasis in the Perioperative Period

Surgical site infections are common, result in increased patient morbidity and mortality, and increase the economic burden to society. Anesthesiologists play a key role in perioperative infection prevention, with data suggesting that evidence-based measures can significantly reduce the incidence of these infections. This systematic review aimed to identify and compare current recommendations for the maintenance of homeostasis in surgical site infection prevention guidelines. Eight surgical site infection prevention guidelines published in the past 10 yr were identified. There was broad consensus regarding the importance of optimizing intraoperative homeostasis to reduce infections. However, there was substantial heterogeneity in both the studies cited and the specific recommendations provided regarding maintenance of oxygenation, normovolemia, normothermia and glycemic targets. High-quality randomized controlled trials are required to close existing knowledge gaps, with adaptive platform trials likely to play a key role in improving the current evidence base for preventing surgical site infection.

A critical approach to research on perioperative pain management

Optimal postoperative pain management is a prerequisite for enhancing functional recovery after surgery. However, many studies assessing analgesic interventions have limitations. Consequently, further improvements in study design are urgently needed. In this focused editorial, we critically review prevalent trial designs and outcome measures including treatment-related adverse events evaluating analgesic interventions. Novel clinical trial designs should improve efficiency and enhance the likelihood of detecting relevant treatment effects. Cohort and database studies using propensity score matching and directed acyclic graphs could provide real-world generalisable information. Procedure-specific and patient-specific trials should allow identification of subpopulations most likely to benefit from a particular intervention after a specific surgical procedure and thus ascertain optimal analgesic strategies in challenging populations.

Global collaboration between platform trials in surgery and anaesthesia

Large, randomised trials are the bedrock of evidence-based medicine, but the resources required to complete such trials greatly limit the number of important clinical questions that can be addressed within a reasonable period of time. Adaptive platform trials can identify effective, ineffective, or harmful treatments faster. These trials have been shown to deliver rapid evidence through the COVID-19 pandemic and are now being adopted across surgery and anaesthesia, with many opportunities for surgeons, anaesthetists, and other perioperative physicians to conduct and collaborate in platform trials.

Exploring the need for reconsideration of trial design in perioperative outcomes research: a narrative review

"Enhanced recovery after surgery" is a multimodal effort to control perioperative pathophysiology and improve outcome. However, despite advances in perioperative care, postoperative complications and the need for hospitalisation and prolonged recovery continue to be challenging. This is further complicated by procedure-specific and patient-associated risk factors, given the increase in the number of elderly and frail patients with multiple comorbidities undergoing surgery. This paper is a critical assessment of current methodology for trials in perioperative medicine. We make a plea to reconsider the design of future interventional trials to improve surgical outcome, based upon studies of potentially effective interventions, but often without improvements in recovery. The complexity of perioperative pathophysiology necessitates a procedure- and patient-specific approach whenever outcome is assessed or interventions are planned. With improved understanding of perioperative pathophysiology, the way to improve outcomes looks promising, provided that knowledge and established enhanced recovery programmes are integrated in trial design.

Funding

None.

Importance of sequential methods in meta-analysis: implications for postoperative mortality, delirium, and stroke management

Trial sequential analysis is an adaptation of frequentist sequential methods that can be used to improve inferences from meta-analysis. Trial sequential analysis can help preserve type I and type II error rates at desired levels for analyses conducted before the required information size. Through three case studies recently published in the British Journal of Anaesthesia, we show how trial sequential analysis can inform the interpretation of meta-analyses. Limitations of trial sequential analysis, which also include those of the meta-analysis to which it is applied, must be carefully considered alongside its benefits.