The EC90 of remifentanil for inhibiting endotracheal intubation responses under anesthesia induction with ciprofol: study protocol for a dose-finding trial with the biased-coin design

BACKGROUND

Tracheal intubation may cause significant hemodynamic responses. Many drugs have been shown to be effective in modifying these cardiovascular responses, including remifentanil, fentanyl, sufentanil, and alfentanil. However, the 90% effect-site concentration (EC90) of remifentanil required to control cardiovascular responses to tracheal intubation when combined with ciprofol remains unclear. The purpose of this study was to determine the EC90 of remifentanil inhibiting cardiovascular responses to tracheal intubation during anesthesia induction with ciprofol using biased-coin design up-and-down sequential method (BC-UDM).

METHODS

This is a prospective sequential allocation dose-finding study. American Society of Anesthesiologists physical status (ASA) I-II elective surgical patients receiving target-controlled infusion (TCI) of remifentanil effect-site concentration (Ce), followed by ciprofol and rocuronium for anesthesia, were enrolled. The cardiovascular response to tracheal intubation was defined as positive when mean arterial pressure (MAP) or heart rate (HR) is 15% higher than the baseline value. Using the BC-UDM, the Ce of remifentanil was determined based on the cardiovascular response to tracheal intubation of the previous patient. The EC90 and 90% confidence intervals (90% CIs) were estimated by R-Foundation centered isotonic regression and the pooled adjacent violators algorithm with bootstrapping.

DISCUSSION

The results of this study sought to demonstrate EC90 of remifentanil blunting sympathetic responses to tracheal intubation during anesthesia index (Ai)-guided ciprofol anesthesia using BCD-UDM. It may help to minimize the cardiovascular responses to tracheal intubation.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2300078275. Registered on December 3, 2023.

Improving medication prescribing-related outcomes for vulnerable elderly in transitions on high-risk medications (IMPROVE-IT HRM): a pilot randomized trial protocol

BACKGROUND

Seniors with recurrent hospitalizations who are taking multiple medications including high-risk medications are at particular risk for serious adverse medication events. We will assess whether an expert Clinical Pharmacology and Toxicology (CPT) medication management intervention during hospitalization with follow-up post-discharge and communication with circle of care is feasible and can decrease drug therapy problems amongst this group.

METHODS

The design is a pragmatic pilot randomized trial with 1:1 patient-level concealed randomization with blinded outcome assessment and data analysis. Participants will be adults 65 years and older admitted to internal medicine services for more than 2 days, who have had at least one other hospitalization in the prior year, taking five or more chronic medications including at least one high-risk medication. The CPT intervention identifies medication targets; completes consult, including priorities for improving prescribing negotiated with the patient; starts the care plan; ensures a detailed discharge medication reconciliation and circle-of-care communication; and sees the patient at least twice after hospital discharge via virtual visits to consolidate the care plan in the community. Control group receives usual care. Primary outcomes are feasibility - recruitment, retention, costs, and clinical - number of drug therapy problems improved, with secondary outcomes examining coordination of transitions in care, quality of life, and healthcare utilization and costs. Follow-up is to 3-month posthospital discharge.

DISCUSSION

If results support feasibility of ramp-up and promising clinical outcomes, a follow-up definitive trial will be organized using a developing national platform and medication appropriateness network. Since the intervention allows a very scarce medical specialty expertise to be offered via virtual care, there is potential to improve the safety, outcomes, and cost of care widely.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov identifier: NCT04077281.

A community health worker and mobile health app intervention to improve adherence to HIV medication among persons with HIV: the CHAMPS study protocol

BACKGROUND

Persons with HIV (PWH) can now achieve a near-normal life expectancy due to antiretroviral therapy (ART). Despite widespread availability of ART in the United States (US), many of the country's approximate 1.1 million PWH are not achieving viral suppression due to poor ART adherence. Viral suppression rates are particularly low in Alabama (AL, 62%) and New York City (NYC, 67%). There is mixed evidence on the efficacy of community health workers (CHW) and mHealth interventions for improving ART adherence and viral suppression in PWH thus, we sought to combine these interventions and test the efficacy for improving health outcomes in PWH.

METHODS

The CHAMPS study is a two-arm randomized controlled trial among 300 PWH with suboptimal primary care appointment adherence (n = 150 in AL and 150 in NYC) over the course of 12 months. Participants are randomly assigned to CHAMPS (intervention) or a standard-of-care (control) arm. Participants in the intervention arm are given a CleverCap pill bottle that syncs to the WiseApp to track medication adherence, reminds users to take their medication at a set time, and enables communication with CHW. All participants complete baseline, 6-month, and 12-month follow-up visits where surveys are administered and, CD4 and HIV-1 viral load are obtained through blood draw.

DISCUSSION

Maintaining ART adherence has significant implications in HIV management and transmission. mHealth technologies have been shown to optimize the provision of health services, produce positive changes in health behavior, and significantly improve health outcomes. CHW interventions also provide personal support to PWH. The combination of these strategies may provide the necessary intensity to increase ART adherence and clinic attendance among PWH at highest risk for low engagement. Delivering care remotely enables CHW to contact, assess, and support numerous participants throughout the day, reducing burden on CHW and potentially improving intervention durability for PWH. The adoption of the WiseApp coupled with community health worker sessions in the CHAMPS study has the potential to improve HIV health outcomes, and will add to the growing knowledge of mHealth and CHW efforts to improve PWH medication adherence and viral suppression.

TRIAL REGISTRATION

This trial was registered with Clinicaltrials.gov (NCT04562649) on 9/24/20.

Coordination of Oral Anticoagulant Care at Hospital Discharge (COACHeD): protocol for a pilot randomised controlled trial

Background

Oral anticoagulants (OACs) are commonly prescribed, have well-documented benefits for important clinical outcomes but have serious harms as well. Rates of OAC-related adverse events including thromboembolic and hemorrhagic events are especially high shortly after hospital discharge. Expert OAC management involving virtual care is a research priority given its potential to reach remote communities in a more feasible, timely, and less costly way than in-person care. Our objective is to test whether a focused, expert medication management intervention using a mix of in-person consultation and virtual care follow-up, is feasible and effective in preventing anticoagulation-related adverse events, for patients transitioning from hospital to home.

Methods and analysis

A randomized, parallel, multicenter design enrolling consenting adult patients or the caregivers of cognitively impaired patients about to be discharged from medical wards with a discharge prescription for an OAC. The interdisciplinary multimodal intervention is led by a clinical pharmacologist and includes a detailed discharge medication reconciliation and management plan focused on oral anticoagulants at hospital discharge; a circle of care handover and coordination with patient, hospital team and community providers; and early post-discharge follow-up virtual medication check-up visits at 24 h, 1 week, and 1 month. The control group will receive usual care plus encouragement to use the Thrombosis Canada website.

The primary feasibility outcomes include recruitment rate, participant retention rates, trial resources management, and the secondary clinical outcomes include adverse anticoagulant safety events composite (AASE), coordination and continuity of care, medication-related problems, quality of life, and healthcare resource utilization. Follow-up is 3 months.

Discussion

This pilot RCT tests whether there is sufficient feasibility and merit in coordinating oral anticoagulant care early post-hospital discharge to warrant a full sized RCT.

Trial registration

NCT02777047.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40814-022-01130-z.

Multi-arm covariate-adaptive randomization

Simultaneously investigating multiple treatments in a single study achieves considerable efficiency in contrast to the traditional two-arm trials. Balancing treatment allocation for influential covariates has become increasingly important in today's clinical trials. The multi-arm covariate-adaptive randomized clinical trial is one of the most powerful tools to incorporate covariate information and multiple treatments in a single study. Pocock and Simon's procedure has been extended to the multi-arm case. However, the theoretical properties of multi-arm covariate-adaptive randomization have remained largely elusive for decades. In this paper, we propose a general framework for multi-arm covariate-adaptive designs which also includes the two-arm case, and establish the corresponding theory under widely satisfied conditions. The theoretical results provide new insights into the balance properties of covariate-adaptive randomization procedures and make foundations for most existing statistical inferences under two-arm covariate-adaptive randomization. Furthermore, these open a door to study the theoretical properties of statistical inferences for clinical trials based on multi-arm covariate-adaptive randomization procedures.

Generalized Efron's biased coin design and its theoretical properties

In clinical trials with two treatment arms, Efron's biased coin design, Efron (1971), sequentially assigns a patient to the underrepresented arm with probability p > ½. Under this design the proportion of patients in any arm converges to ½, and the convergence rate is n-1, as opposed to n-½ under some other popular designs. The generalization of Efron's design to K ≥ 2 arms and an unequal target allocation ratio (q1, . . ., qK) can be found in some papers, most of which determine the allocation probabilities ps in a heuristic way. Nonetheless, it has been noted that by using inappropriate ps, the proportion of patients in the K arms never converges to the target ratio. We develop a general theory to answer the question of what allocation probabilities ensure that the realized proportions under a generalized design still converge to the target ratio (q1, . . ., qK) with rate n-1.

Start-up designs for response-adaptive randomization procedures with sequential estimation

Response-adaptive randomization procedures are appropriate for clinical trials in which two or more treatments are to be compared, patients arrive sequentially and the response of each patient is recorded before the next patient arrives. However, for those procedures that involve sequential estimation of model parameters, start-up designs are commonly required in order to provide initial estimates of the parameters. In this paper, a suite of such start-up designs for two treatments and binary patient responses are considered and compared in terms of the numbers of patients required in order to give meaningful parameters estimates, the number of patients allocated to the better treatment, and the bias in the parameter estimates. It is shown that permuted block designs with blocks of size 4 are to be preferred over a wide range of parameter values. For the case of two treatments, normal responses and selected start-up procedures, a design incorporating complete randomization followed appropriately by repeats of one of the treatments yields the minimum expected number of patients and is to be preferred.

Balance and randomness in sequential clinical trials: the dominant biased coin design

Efron's biased coin design (BCD) is a well-known randomization technique that helps neutralize selection bias, while keeping the experiment fairly balanced for every sample size. Several extensions of this rule have been proposed, and their properties were analyzed from an asymptotic viewpoint and compared via simulations in a finite setup. The aim of this paper is to push forward these comparisons by taking also into account the adjustable BCD, which is never considered up to now. Firstly, we show that the adjustable BCD performs better than Efron's coin with respect to both loss of precision and randomness. Moreover, the adjustable BCD is always more balanced than the other coins and, only for some sample sizes, slightly more predictable. Therefore, we suggest the dominant BCD, namely a new and flexible class of procedures that can change the allocation rule step by step in order to ensure very good performance in terms of both balance and selection bias for any sample size. Our simulations demonstrate that the dominant BCD is more balanced and, at the same time, less or equally predictable than Atkinson's optimum BCD.

Adaptive randomization for clinical trials

In February 2010, the U.S. Food and Drug Administration (FDA, 2010 ) drafted guidance that discusses the statistical, clinical, and regulatory aspects of various adaptive designs for clinical trials. An important class of adaptive designs is adaptive randomization, which is considered very briefly in subsection VI.B of the guidance. The objective of this paper is to review several important new classes of adaptive randomization procedures and convey information on the recent developments in the literature on this topic. Much of this literature has been focused on the development of methodology to address past criticisms and concerns that have hindered the broader use of adaptive randomization. We conclude that adaptive randomization is a very broad area of experimental design that has important application in modern clinical trials.

The impact of randomization on the analysis of clinical trials

The design of a comparative clinical trial involves a method of allocating treatments to patients. Usually, this assignment is performed to achieve several objectives: to minimize selection and accidental bias, to achieve balanced treatment assignment in order to maximize the power of the comparison, and most importantly, to obtain the basis for a valid statistical inference. In this paper, we are concerned exclusively with the last point. In our investigation, we will assume that measurements can be decomposed in a patient-specific effect, a treatment effect, and a measurement error. If the patient can be considered to be randomly drawn from a population, the randomization method does not affect the analysis. In fact, under this so-called population model, randomization would be unnecessary to obtain a valid inference. However, when individuals cannot be considered randomly selected, the patient effects may become fixed but unknown constants. In this case, randomization is necessary to obtain valid statistical analyses, and it cannot be precluded that the randomization method has an impact on the results. This paper elaborates that the impact can be substantial even for a two-sample comparison when a standard t-test is used for data analysis. We provide some theoretical results as well as simulations.