Hemodynamic monitoring in the intensive care unit

Distal radial approach for arterial pressure monitoring with a long catheter provides safe and stable monitoring in the intensive care unit: A single-center retrospective study

BACKGROUND

To compare the distal radial artery approach (DRA) with a longer catheter to DRA with a shorter catheter in arterial catheter (AC) placement in the intensive care unit (ICU).

METHODS

This was a single-center retrospective cohort study of DRA with a long catheter (60 mm) for arterial catheterization in the ICU. DRA with a short catheter (25-30 mm) was used in the control group, and the groups were compared using multivariate regression analysis. The primary study endpoint was the incidence of unplanned AC removal. The secondary endpoint was the incidence of other inappropriate events, namely loss of arterial pressure waveforms, bleeding, catheter-related infection, pressure ulcer, and other complications associated with the AC.

RESULTS

In this study, the DRA with a long catheter was used in 50 patients. No unplanned AC removals or other inappropriate events occurred, and there were no complications associated with the DRA. The DRA procedural success rate was 100%. There was no significant difference in hemostasis times between the groups. Loss of arterial waveforms was an early predictor of unplanned AC removal.

CONCLUSIONS

The DRA with a long catheter provided stable monitoring and was associated with a low unplanned removal rate. This method has the advantages of fewer complications and shorter hemostasis time compared with the DRA with a short catheter, and may become a new AC option in the ICU.

Safety during interhospital helicopter transfer of ventilated COVID-19 patients. No clinical relevant changes in vital signs including non-invasive cardiac output

Background

During the COVID-19 pandemic in The Netherlands, critically ill ventilated COVID-19 patients were transferred not only between hospitals by ambulance but also by the Helicopter Emergency Medical Service (HEMS). To date, little is known about the physiological impact of helicopter transport on critically ill patients and COVID-19 patients in particular. This study was conducted to explore the impact of inter-hospital helicopter transfer on vital signs of mechanically ventilated patients with severe COVID-19, with special focus on take-off, midflight, and landing.

Methods

All ventilated critically ill COVID-19 patients who were transported between April 2020 and June 2021 by the Dutch ‘Lifeliner 5’ HEMS team and who were fully monitored, including noninvasive cardiac output, were included in this study. Three 10-min timeframes (take-off, midflight and landing) were defined for analysis. Continuous data on the vital parameters heart rate, peripheral oxygen saturation, arterial blood pressure, end-tidal CO₂ and noninvasive cardiac output using electrical cardiometry were collected and stored at 1-min intervals. Data were analyzed for differences over time within the timeframes using one-way analysis of variance. Significant differences were checked for clinical relevance.

Results

Ninety-eight patients were included in the analysis. During take-off, an increase was noticed in cardiac output (from 6.7 to 8.2 L min⁻¹; P < 0.0001), which was determined by a decrease in systemic vascular resistance (from 1071 to 739 dyne·s·cm⁻⁵, P < 0.0001) accompanied by an increase in stroke volume (from 88.8 to 113.7 mL, P < 0.0001). Other parameters were unchanged during take-off and mid-flight. During landing, cardiac output and stroke volume slightly decreased (from 8.0 to 6.8 L min⁻¹, P < 0.0001 and from 110.1 to 84.4 mL, P < 0.0001, respectively), and total systemic vascular resistance increased (P < 0.0001). Though statistically significant, the found changes were small and not clinically relevant to the medical status of the patients as judged by the attending physicians.

Conclusions

Interhospital helicopter transfer of ventilated intensive care patients with COVID-19 can be performed safely and does not result in clinically relevant changes in vital signs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02177-5.

Arterial insertion method: A new method for systematic evaluation of ultrasound-guided radial arterial catheterization

Introduction:

Peripheral arterial catheter insertion is a common procedure for critically ill patients requiring frequent blood gas sampling and continuous blood pressure monitoring. There are clear advantages of ultrasound-guided arterial cannulation, which have shown to be more effective in reducing complications, time to successful cannulation, number of attempts, and overall first-time success rates. Evidence suggests that using palpation alone has a first-time success rate of less than 70% yet is still a widely performed technique. A systematic evaluation may be required to reduce variations in arterial catheterization practices.

Design:

The arterial insertion method is a systematic evaluation to aid in arterial catheter insertion with ultrasound guidance, intended to improve the procedural approach. The process of arterial insertion method ensures appropriate choice of zone selection to optimize catheter longevity and performance in patients requiring arterial access. Moving the insertion site proximally 4 cm from the red zone into the green zone may reduce mechanical complications and preserve catheter performance and dwell time.

Conclusion:

The standardization of ultrasound guidance in arterial catheterization promotes vessel health and patient safety through device and site optimization. The arterial insertion method systematic evaluation may be utilized to reduce variation in practice and promote the use of ultrasound as a standard for the insertion of radial arterial catheters.

Radial artery cannulation in intensive care unit patients: Does distance from wrist joint increase catheter durability and functionality?

INTRODUCTION

Radial artery cannulation (RAC) is a common procedure in Intensive Care Units (ICU); radial catheters for ICU patients require increased durability to collect blood samples and to guarantee continuous hemodynamic monitoring. Failure in catheter functionality needs catheter replacement, impacting on staff workload, costs, and patient safety and discomfort.

METHODS

prospective non-randomised cohort study on adult ICU patients describing intensivists and critical care nurses' approach in radial artery catheterization.

RESULTS

A sample of 103 radial artery cannulations was observed. Catheterization was performed blind in 71 patients (68.9%) and with ultrasound guidance (USG) in 32 (31.1%); majority of blind inserted RAC were at a distance between 0 and 3.9 cm from wrist joint (77.5%) while catheters inserted from 4 to 10 cm were mainly positioned with USG (84.4%). Radial catheters inserted with USG at a distance of 4 to 10 cm from wrist joint had an in-situ time double than those inserted blind (8.2 ± 7.5 vs 4.8 ± 7.3, p < 0.038).

CONCLUSIONS

As recommended by current evidence and guidelines, USG represents a valuable support during arterial catheterization and is recommended in adult patients with clinical signs of shock, obese, swelling, and in the paediatric population. RAC in the forearm proximally, at a distance of at least 4 cm from wrist, could increase catheter durability and functionality for ICU patients. USG for cannulation in this forearm area is mandatory because of the deeper course of the radial artery.

Reliability of Continuous Non-Invasive Assessment of Hemoglobin and Fluid Responsiveness: Impact of Obesity and Abdominal Insufflation Pressures

BACKGROUND

During surgery, proper fluid resuscitation and hemostatic control is critical. Pleth variability index (PVI) is advocated as a reliable way of optimizing intraoperative fluid resuscitation. PVI is a measure of dynamic change in perfusion index during a complete respiratory cycle. Non-invasive monitoring of total hemoglobin could provide a reliable means to determine need for transfusion. We analyzed the impact of insufflation and obesity on non-invasive measurements of hemoglobin and PVI in laparoscopic procedures to validate reliability of fluid responsiveness and hemoglobin levels.

METHODS

A non-invasive hemoglobin and PVI monitoring device was prospectively analyzed in patients undergoing abdominal operations. Patients were stratified by open and laparoscopic approach and obesity (body mass index (BMI) ≥35). PVI and hemoglobin values were assessed before, during, and after insufflation and compared to control patients undergoing open surgery.

RESULTS

Sixty-three patients were enrolled (mean age 42 years; 71 % male; mean BMI 36) with 24 patients laparoscopic non-obese (LNO), 20 laparoscopic obese (LO), and 19 undergoing open operations. There was no significant blood loss. Hemoglobin did not change significantly before or after insufflation. There was false elevation of PVI with insufflation and more pronounced in obese patients.

CONCLUSIONS

Insufflation or obesity was not associated with significant variations in hemoglobin. Non-invasive monitoring of hemoglobin is useful in laparoscopic procedures in obese and non-obese patients. PVI values should be used cautiously during laparoscopic procedures, particularly in obese patients.