Optimization of procedural sedation and analgesia during atrial fibrillation ablation.

PURPOSE OF REVIEW: This mini-review is aimed to provide an overview and discuss procedural sedation and analgesia for atrial fibrillation (AF) ablation with focus at qualification of staff, patient evaluation, monitoring, medication and postprocedural care. RECENT FINDINGS: Sleep-disordered breathing is highly prevalent in patients with AF. Impact of often used STOP-BANG questionnaire to detect sleep-disordered breathing in AF patients is limited due to its restricted validity. Dexmedetomidine is a commonly used drug in sedation, but is shown not to be superior to propofol in sedation during AF-ablation. Alternatively use of remimazolam has characteristics that makes it a promising drug for minimal to moderate sedation for AF-ablation. High flow nasal oxygen (HFNO) has shown to reduce the risk of desaturation in adults receiving procedural sedation and analgesia. SUMMARY: An optimal sedation strategy during AF ablation should be based on AF patient characteristics, the level of sedation needed, the procedure (duration and type of ablation) and the education and experience of the sedation provider. Patient evaluation and post procedural care are part of sedation care. More personalized care based on use of various sedation strategies and types of drugs as related to the type of AF-ablation is the way to further optimize care.

High-flow nasal cannula versus standard low-flow nasal cannula during deep sedation in patients undergoing radiofrequency atrial fibrillation catheter ablation: a single-centre randomised controlled trial.

BACKGROUND: To our knowledge, there are few trials studying the effect of high-flow nasal cannula (HFNC) during deep sedation. Our hypothesis is that high-flow nasal cannula (HFNC) will prevent hypoxemia and desaturation as compared to low-flow nasal cannula (LFNC) during prolonged deep sedation in patients with atrial fibrillation undergoing radiofrequency catheter ablation (RFCA). METHODS: A single-centre, randomised controlled trial with HFNC as the intervention and LFNC as the control group. A total of 94 adult patients per group undergoing elective radiofrequency atrial fibrillation catheter ablation under deep sedation. will be included. The primary outcome is the lowest oxygen saturation (SpO2). Secondary outcomes are as follows: the duration of lowest SpO2, cross over from oxygen therapy in both directions, incidence of SpO2 below 90% > 60 seconds, adverse sedation events, adverse effects of HFNC, mean CO2, peak CO2 and patients experience with oxygen therapy. The study will take place during the 2-day admission period for RFCA. Patients can fill out their questionnaires in the first week after treatment. DISCUSSION: HFNC is increasingly used as a technique for oxygen delivery in procedural sedation and analgesia. We hypothesise that HFNC is superior to the standard treatment LFNC in patients under deep sedation with respect to the incidence of desaturation. To our knowledge, there are no adequately powered clinical trial studies on the effects of HFNC in prolonged deep sedation. TRIAL REGISTRATION: ClinicalTrials.gov NCT04842253. Registered on 04 April 2021.

Boundaries of the thoracic paravertebral space: potential risks and benefits of the thoracic paravertebral block from an anatomical perspective.

PURPOSE: Thoracic paravertebral block (TPVB) may be an alternative to thoracic epidural analgesia. A detailed knowledge of the anatomy of the TPV-space (TPVS), content and adnexa is essential in understanding the clinical consequences of TPVB. The exploration of the posterior TPVS accessibility in this study allows (1) determination of the anatomical boundaries, content and adnexa, (2) description of an ultrasound-guided spread of low and high viscous liquid. METHODS: In two formalin-fixed specimens, stratification of the several layers and the 3D-architecture of the TPVS were dissected, observed and photographed. In a third unembalmed specimen, ultrasound-guided posterolateral injections at several levels of the TPVS were performed with different fluids. RESULTS: TPVS communicated with all surrounding spaces including the segmental dorsal intercostal compartments (SDICs) and the prevertebral space. TPVS transitions to the SDICs were wide, whereas the SDICs showed narrowed transitions to the lateral intercostal spaces at the costal angle. Internal subdivision of the TPVS in a subendothoracic and an extra-pleural compartment by the endothoracic fascia was not observed. Caudally injected fluids spread posteriorly to the costodiaphragmatic recess, showing segmental intercostal and slight prevertebral spread. CONCLUSIONS: Our detailed anatomical study shows that TPVS is a potential space continuous with the SDICs. The separation of the TPVS in a subendothoracic and an extra-pleural compartment by the endothoracic fascia was not observed. Based on the ultrasound-guided liquid spread we conclude that the use of a more lateral approach might increase the probability of intravascular puncture or catheter position.

Functional recovery of stored platelets after transfusion.

BACKGROUND: Platelet (PLT) concentrates are prophylactically given to prevent major bleeding complications. The corrected count increment (CCI) is currently the only tool to monitor PLT transfusion efficacy. PLT function tests cannot be performed in patients with thrombocytopenia. Therefore, an optimized agonist-induced assay was used to determine PLT function, in patients with severe thrombocytopenia before and after transfusion. STUDY DESIGN AND METHODS: PLT reactivity toward adenosine diphosphate (ADP), thrombin receptor-activating peptide SFLLRN (TRAP), and convulxin (CVX) was assessed by flow cytometry. P-selectin expression was measured on PLTs from 11 patients with thrombocytopenia before and 1 hour after transfusion, on stored PLTs, and on stored PLTs incubated for 1 hour in whole blood from patients ex vivo. RESULTS: The mean (±SEM) CCI after 1 hour was 11.4 (±1.5). After transfusion, maximal agonist-induced PLT P-selectin expression was on average 29% higher for ADP (p = 0.02), 25% higher for TRAP (p = 0.007), and 24% higher for CVX (p = 0.0008). ADP-induced reactivity of stored PLTs increased with 46% after ex vivo incubation (p = 0.007). These PLTs also showed an overall higher P-selectin expression compared to PLTs 1 hour after transfusion (p = 0.005). After normalization for this background expression, a similar responsiveness was observed. CONCLUSIONS: Our study shows recovery of PLT function after transfusion in patients with thrombocytopenia. The majority of functional PLTs measured after transfusion most likely represents stored transfused PLTs that regained functionality in vivo. The difference in baseline P-selectin expression in vivo versus ex vivo suggests a rapid clearance from circulation of PLTs with increased P-selectin expression.

Continuous paravertebral block for postoperative pain compared to general anaesthesia and wound infiltration for major oncological breast surgery.

We hypothesized that improved acute postoperative pain relief will be achieved using general anaesthesia (GA) either in combination with continuous thoracic paravertebral block (GA-cPVB) or single shot (GA-sPVB) as compared to GA supplemented by local wound infiltration (GA-LWI) after unilateral major breast cancer surgery. A randomised controlled trial was conducted in 46 adult women in a day-care or short-stay hospital setting after major breast cancer surgery. Pain-intensity was measured using an 11-point visual analogue scale (VAS) until postoperative day 2. GA-sPVB was stopped due to slow inclusion. No significant difference in VAS score was noted between GA-LWI (VAS median 0.5 (interquartile range 0.18-2.00)) and GA-cPVB, (VAS 0.3 (0.00-1.55, p = 0.195)) 24 hours after surgery or at any point postoperatively until postoperative day 2. We conclude that both GA-LWI and GA-cPVB anaesthetic techniques are equally effective in treatment of acute postoperative pain after major oncological breast surgery. As GA-LWI is easily to perform with fewer complications and it is more cost-effective it should be preferred over GA-cPVB.

Reduced incidence of chronic postsurgical pain after epidural analgesia for abdominal surgery.

BACKGROUND: Chronic postsurgical pain (CPSP) is a common complication of surgery with high impact on quality of life. Peripheral and central sensitization caused by enhanced and prolonged afferent nociceptive input are considered important mechanisms for the development of CPSP. This case-control study investigated whether epidural analgesia is associated with a reduced incidence of CPSP after open abdominal surgery. METHODS: Six months after surgery, Short-Form-36 Health Survey (SF-36) pain scores, possible predictors of chronic pain, and quality of life were assessed. Patients treated with epidural analgesia in combination with general anesthesia (epidural group, N = 51) were compared to patients undergoing matched surgical procedures receiving general anesthesia alone (GA-group, N = 50). Multivariate analysis was performed by logistic regression analysis. RESULTS: Twenty-six (25.7%) patients experienced chronic pain, 9 in the epidural group (17.6%), 17 in the GA-group (34%), crude odds ratio (OR) 0.42 (95% confidence interval (CI) 0.16 to 1.05). After adjustment for the most prominent predictors of CPSP, such as age, sex, pre-operative pain, and acute postoperative pain, the OR for chronic pain in the epidural group was 0.19 (95% CI 0.05 to 0.76). Patients with CPSP reported a significantly lower quality of life compared to patients without CPSP (SF-36 total score median (IQR) 39.2 (27.2 to 56.7) vs. 84.3 (69.9 to 92.5, P < 0.001) and a lower level of long-term global perceived recovery (70.0% (50.0 to 80.0) vs. 90.0% (80.0 to 100.0), P < 0.001). CONCLUSION: Chronic postsurgical pain occurs in a significant number of patients 6 months after open abdominal surgery. Postoperative epidural analgesia is associated with a reduced incidence of CPSP after abdominal surgery.

Evaluation of a non-invasive bladder volume measurement in children.

OBJECTIVE: Postoperative urinary retention (PUR) is associated with overdistension of the bladder. The prevention of PUR by routine catheterization may increase the risk of urinary tract infection. Postoperative monitoring of the bladder volume by ultrasound to prevent PUR is reliable in adults, but has not been evaluated in children. MATERIAL AND METHODS: The BladderScan BVI 6200, an ultrasound device specifically designed for children, was assessed. Forty patients who required urinary catheter placement during surgery or during intensive care unit stay were entered into this blinded calibration study. An assessment of bladder urine volume by ultrasound was performed before and after catheterization in surgical patients. In these patients and intensive care patients 0, 2.5 or 5 ml/kg sterile normal NaCl was injected through the bladder catheter and the catheter was clamped. Volumes estimated with ultrasound were compared with measured catheter drainage or/and injected volume after the scan. RESULTS: The mean relative difference (bias) between the ultrasound estimate and the injected volume was -20% (95% confidence interval 140 to -180%). Precision, estimated using the Wilcoxon signed ranks test, showed a significant difference (Z = -3.25, p = 0.001) between the ultrasound-estimated volumes and the injected volumes. CONCLUSIONS: This study could not confirm good agreement between the ultrasound-estimated volumes and the injected volumes at volumes below 5 ml/kg. Bladder volumes were underestimated with a very broad 95% confidence interval. The ultrasound device should not replace current clinical assessment.