Medical Emergencies and Cardiopulmonary Arrests in Interventional Radiology

Development and Validation of an Electronic Adverse Event Model for Patient Safety Surveillance in Interventional Radiology

BACKGROUND

Comprehensive adverse event (AE) surveillance programs in interventional radiology (IR) are rare. Our aim was to develop and validate a retrospective electronic surveillance model to identify outpatient IR procedures that are likely to have an AE, to support patient safety and quality improvement.

METHODS

We identified outpatient IR procedures performed in the period from October 2017 to September 2019 from the Veterans Health Administration (n = 135,283) and applied electronic triggers based on posyprocedure care to flag cases with a potential AE. From the trigger-flagged cases, we randomly sampled n = 1,500 for chart review to identify AEs. We also randomly sampled n = 600 from the unflagged cases. Chart-reviewed cases were merged with patient, procedure, and facility factors to estimate a mixed-effects logistic regression model designed to predict whether an AE occurred. Using model fit and criterion validity, we determined the best predicted probability threshold to identify cases with a likely AE. We reviewed a random sample of 200 cases above the threshold and 100 cases from below the threshold from October 2019 to March 2020 (n = 20,849) for model validation.

RESULTS

In our development sample of mostly trigger-flagged cases, 444 of 2,096 cases (21.8%) had an AE. The optimal predicted probability threshold for a likely AE from our surveillance model was >50%, with positive predictive value of 68.9%, sensitivity of 38.3%, and specificity of 95.3%. In validation, chart-reviewed cases with AE probability >50% had a positive predictive value of 63% (n = 203). For the period from October 2017 to March 2020, the model identified approximately 70 IR cases per month that were likely to have an AE.

CONCLUSIONS

This electronic trigger-based approach to AE surveillance could be used for patient-safety reporting and quality review.

Brachial plexus block using only 1% lidocaine to reduce pain during the endovascular treatment of dysfunctional arteriovenous access

BACKGROUND

Interventional endovascular treatments of dysfunctional arteriovenous (AV) access for hemodialysis can cause pain and discomfort to the patients. Ultrasound-guided brachial plexus block (BPB) is an alternative regional anesthesia method, but conventional BPB using ropivacaine or bupivacaine may cause long-lasting motor power loss, significantly reducing patient satisfaction. This study aimed to introduce BPB using only 1% lidocaine, which induces sensory loss while minimizing motor block, and evaluate the efficacy and safety of this procedure.

METHODS

This retrospective study was conducted on 277 consecutive patients with dysfunctional AV access requiring percutaneous transluminal angioplasty (PTA). Of these, 174 patients underwent the BPB procedure using 1% lidocaine. Time data were recorded, and the motor strength grade (MRC scale, grade 0-5) was evaluated. Numeric rating pain score (NRPS, grade 0-10) was asked during every PTA, and overall NRPS and satisfaction scores (scale 1-3) were asked after the procedure was completed.

RESULTS

Of the 174 patients who received BPB, the success rate was 100%, and there were no significant complications related to BPB. The MRC scale measured at the time when the complete sensory loss was achieved was 1.99 ± 0.63, and that at the point of sensory recovery when the block effect expired was 3.93 ± 0.62, indicating a good grade of motor strength. The average NRPS during PTA in the BPB group was significantly lower than that of the control group without BPB (1.04 ± 2.04vs 6.30 ± 2.71, p < 0.001). The overall satisfaction score was significantly higher in the BPB group than in the control group (2.79 ± 0.50vs 2.00 ± 0.81, p < 0.001).

CONCLUSIONS

BPB using only 1% lidocaine can induce a sensory block while minimizing the effect on motor function. It can be applied safely in an outpatient clinic setting with relatively higher satisfaction.

Development of a Periprocedure Trigger for Outpatient Interventional Radiology Procedures in the Veterans Health Administration

OBJECTIVES

Interventional radiology (IR) is the newest medical specialty. However, it lacks robust quality assurance metrics, including adverse event (AE) surveillance tools. Considering the high frequency of outpatient care provided by IR, automated electronic triggers offer a potential catalyst to support accurate retrospective AE detection.

METHODS

We programmed previously validated AE triggers (admission, emergency visit, or death up to 14 days after procedure) for elective, outpatient IR procedures performed in Veterans Health Administration surgical facilities between fiscal years 2017 and 2019. We then developed a text-based algorithm to detect AEs that explicitly occurred in the periprocedure time frame: before, during, and shortly after the IR procedure. Guided by the literature and clinical expertise, we generated clinical note keywords and text strings to flag cases with high potential for periprocedure AEs. Flagged cases underwent targeted chart review to measure criterion validity (i.e., the positive predictive value), to confirm AE occurrence, and to characterize the event.

RESULTS

Among 135,285 elective outpatient IR procedures, the periprocedure algorithm flagged 245 cases (0.18%); 138 of these had ≥1 AE, yielding a positive predictive value of 56% (95% confidence interval, 50%-62%). The previously developed triggers for admission, emergency visit, or death in 14 days flagged 119 of the 138 procedures with AEs (73%). Among the 43 AEs detected exclusively by the periprocedure trigger were allergic reactions, adverse drug events, ischemic events, bleeding events requiring blood transfusions, and cardiac arrest requiring cardiopulmonary resuscitation.

CONCLUSIONS

The periprocedure trigger performed well on IR outpatient procedures and offers a complement to other electronic triggers developed for outpatient AE surveillance.

Infectious Recidivism in Tunneled Dialysis Catheters Removed for Bloodstream Infection in the Intensive Care Unit

PURPOSE

To determine the rate of recurrent infection of ICU patients who underwent tunneled dialysis catheter (TDC) exchange or removal for bloodstream infection.

MATERIALS AND METHODS

Forty seven patients, with a total of 61 TDCs removed for bloodstream infection while admitted in an ICU from 2017-2020, were identified. TDCs were exchanged over a wire or removed and replaced. Thirteen patients (21%) were managed with non-tunneled dialysis catheters (NTDCs) until delayed TDC replacement at ICU departure. Forty seven TDCs were removed for bacteremia (77%), 13 for fungemia (21%), and 1 for both (2%). Thirty TDCs (49%) were exchanged over-the-wire (ICU-exchanged TDCs), and 31 (51%) were removed. Of the patients who underwent TDC removal, 9 had a new TDC placed while still admitted in the ICU (ICU-replaced TDCs), and 7 underwent delayed TDC replacement at ICU departure. Data regarding infection, removal technique, catheter replacement, and patient outcomes were analyzed.

RESULTS

There were 10 instances of recurrent bloodstream infection (infectious recidivism), occurring in 7 ICU-exchanged TDCs (7/30, 23%) and 3 ICU-replaced TDCs (3/9, 33%). Bloodstream infection complicated 22% of NTDCs used in patients undergoing delayed TDC replacement. No cases of TDC infectious recidivism were observed in patients who underwent delayed TDC replacement (0/7, 0%) after ICU departure.

CONCLUSIONS

High rates of infectious recidivism exist in the ICU, meriting further investigation into how to optimally manage these patients. In those in whom TDCs are removed, withholding TDC replacement until ICU departure may help to minimize the rate of recurrent infection.

Efficacy and Safety of Ultrasound-Guided Supraclavicular Brachial Plexus Block during Angioplasty of Dysfunctional Arteriovenous Access: A Prospective, Randomized Single-Center Clinical Trial

PURPOSE

To evaluate the efficacy and safety of the ultrasound-guided supraclavicular brachial plexus block (BPB) during angioplasty of dysfunctional arteriovenous access.

MATERIALS AND METHODS

Eighty study participants with dysfunctional arteriovenous access were enrolled in this prospective, randomized clinical trial between November 2016 and February 2018. Eighty patients were randomized to either the ultrasound-guided supraclavicular BPB group (mean age ± standard deviation [SD], 65.1 ± 12.4; male:female = 17:23) or the no regional anesthesia group (mean age ± SD, 64.0 ± 11.7; male:female = 25:15). Pain was assessed on the 10-point Visual Analogue Scale. Participant satisfaction was examined. Six-month clinical follow-up was done to evaluate arteriovenous access patency and long-term complications.

RESULTS

The BPB group showed a lower average pain score than the control group (mean ± SD, 0.9 ± 1.9 vs 6.4 ± 2.5; P < .001). Participant satisfaction (mean ± SD, 2.8 ± 0.5 vs 2.1±0.8; P < .001) was also higher in the BPB group. Six-month patency was 65% (26/40) in the BPB group and 59% (23/39) in the control group, with no significant difference between the 2 groups (P = .59). No major immediate or delayed complications were observed.

CONCLUSIONS

Ultrasound-guided BPB is highly effective in reducing pain during angioplasty of dysfunctional arteriovenous access with an acceptable safety profile.

Complications in Percutaneous Dialysis Interventions: How to Avoid Them, and How to Treat Them When They do Occur

Because of the increasing prevalence of end-stage renal disease, more percutaneous interventions are being performed. They serve an important role, allowing for restoration of access function, which is achieved with high level of technical success. However, complications are inevitable during any types of procedure, and percutaneous dialysis interventions are no exception. To provide safe and effective care these patients need, anyone performing endovascular dialysis interventions needs to understand the possible complications, how they can be avoided, and how they can be addressed if they are to occur. Topics in this article include complications seen while intervening on the thrombosed access, complications of angioplasty, potentially devastating complications of central venous interventions, and complications of dialysis catheter placement. Further, patients with end-stage renal disease are generally sicker than the average patient, usually afflicted by multiple comorbidities and are therefore more complicated from a medical perspective. This places them at higher risk for acute cardiopulmonary decompensation or arrest than any other interventional radiology patient subset. As result, we also briefly review general medical complications in this population.

Role of interventional nephrology in the multidisciplinary approach to hemodialysis vascular access care

Dialysis vascular access planning, creation, and management is of critical importance to the dialysis patient population. It requires a multidisciplinary approach involving patients and their families, dialysis facility staff, the nephrologist, the surgeon, and the interventionalist. With the emergence of interventional nephrology as a subspecialty of nephrology, the nephrologist is increasingly providing both the nephrology and interventional aspects of care, and in some areas, the surgical functions as well. Most of these interventional nephrologists work in freestanding outpatient dialysis access centers (DACs). Large clinical studies published over the past 10 years demonstrate that the interventional nephrologist can manage the problems associated with dialysis access dysfunction effectively, safely, and economically. A recently published study based upon United States Medicare claims data in which a DAC patient group (n = 27,613) and a hospital outpatient department patient group (HOPD group; n = 27,613) were compared using propensity score matching techniques showed that patients treated in the DACs had significantly better clinical outcomes (P<0.001). This included fewer vascular access-related infections (0.18 vs. 0.29), fewer septicemia-related hospitalizations (0.15 vs. 0.18), and a lower mortality rate (47.9% vs. 53.5%).

Management of anesthetic emergencies and complications outside the operating room

PURPOSE OF REVIEW

Anesthesia outside the operating room is commonly uncomfortable and risky. In this setting, anesthetic emergencies or complications may occur. This review aims to report the most recent updates regarding the management of prehospital anesthesia, anesthesia in the trauma and emergency rooms, and anesthesia for endoscopy and interventional radiology.

RECENT FINDINGS

After tracheal intubation failure, airway control of outpatients could be achieved by pharmacologically assisted laryngeal mask insertion. Management of traumatic injured patients is best guided in the frame of checklists. Monitoring sedation in this setting is challenging notably because of the threat of haemodynamic instability. Unfortunately, BIS monitoring cannot be recommended to guide sedation in this setting. Ketamine can be used to prevent hypotension during prehospital anesthesia or procedural sedation, especially as its neuroprotective effects have been recently best understood. Target-controlled infusion propofol administration with small concentration increments is adapted to prevent hypotension and hypoxaemia during sedation for gastrointestinal endoscopy and interventional radiology. Target-controlled infusion remifentanil administration is also adapted to many procedures.

SUMMARY

Anesthesia outside the operating room requires careful monitoring to avoid side-effects and education of nonanaesthetists when they are involved. A useful tool is to continuously improve the protocols and checklists to make anesthesia in this setting safer.