Perfusion index versus non-invasive hemodynamic parameters during insertion of i-gel, classic laryngeal mask airway and endotracheal tube

HEMORRHAGIC SHOCK ASSESSED BY TISSUE MICROCIRCULATORY MONITORING: A NARRATIVE REVIEW

ABSTRACT

Hemorrhagic shock (HS) is a common complication after traumatic injury. Early identification of HS can reduce patients' risk of death. Currently, the identification of HS relies on macrocirculation indicators such as systolic blood pressure and heart rate, which are easily affected by the body's compensatory functions. Recently, the independence of the body's overall macrocirculation from microcirculation has been demonstrated, and microcirculation indicators have been widely used in the evaluation of HS. In this study, we reviewed the progress of research in the literature on the use of microcirculation metrics to monitor shock. We analyzed the strengths and weaknesses of each metric and found that microcirculation monitoring could not only indicate changes in tissue perfusion before changes in macrocirculation occurred but also correct tissue perfusion and cell oxygenation after the macrocirculation index returned to normal following fluid resuscitation, which is conducive to the early prediction and prognosis of HS. However, microcirculation monitoring is greatly affected by individual differences and environmental factors. Therefore, the current limitations of microcirculation assessments mean that they should be incorporated as part of an overall assessment of HS patients. Future research should explore how to better combine microcirculation and macrocirculation monitoring for the early identification and prognosis of HS patients.

Assessment of stress response due to C-Mac D-blade guided videolaryngoscopic endotracheal intubation and docking of da Vinci surgical robot using perfusion index in patients undergoing transoral robotic oncosurgery

Clinical utility of perfusion index (PI) has entered a new realm as a non-invasive, quantitative index of stress response to endotracheal intubation. Transoral robotic surgery (TORS) involves F-K retractor aided docking of the surgical robot producing haemodynamic and stress responses akin to laryngoscopy. We compared the stress response to videolaryngoscopy with that due to docking of da Vinci surgical robot using PI, heart rate and mean arterial pressure evaluated at specific time points post-laryngoscopy and post-docking. Twenty-six adult patients, scheduled for TORS under general endotracheal anaesthesia were included in this prospective, observational, single-centric cohort study. Statistical analysis included paired samples t-test, dotted box-whisker plots, trendlines and correlograms for comparative analysis of two stressors, laryngoscopy and docking. Baseline PI was 4.14. PI values increased post-midazolam (4.23), 1 min (5.69) and 3 min (6.25) post anaesthetic-induction, plummeted at laryngoscopy (3.24), remained low at 1 min (3.68), 3 min (4.69) thereafter, and were highest at 10 min (6.17) post-laryngoscopy and predocking (6.84). Docking witnessed a fall in PI (4.1), which remained low at 1 min (4.02), 3 min (4.31) and 10 min (4.79) post-docking. PI was significantly higher at laryngoscopy compared with PI at docking (p = 0.0044). At 1 min and 3 min post-laryngoscopy and post-docking, respectively, the differences in PI were statistically insignificant. PI at 10 min post-laryngoscopy was significantly lower than PI at 10 min post-docking (p < 0.0001). As non-invasively quantified by PI, videolaryngoscopic stress response is more intense but shorter-lived versus that due to docking. PI displays a negative correlation with haemodynamic variables. PI at laryngoscopy is a good predictor of PI at docking, enabling pre-emptive measures (fentanyl bolus; deepening of volatile anaesthesia from MAC-maintenance to MAC-intubation) anticipating the docking-induced stress response.Trial registration http://ctri.nic.in ; Identifier: CTRI/2019/11/022091.

Perfusion index during endotracheal intubation and extubation: A prospective observational study

Introduction

Perfusion index (PI) can be detected using a pulse oximeter. Its value decreases in response to noxious stimuli. Here, we investigated its efficacy in detecting hemodynamic responses during endotracheal intubation and extubation.

Methods

An approval from the institutional ethics committee was obtained along with a written informed consent from the patients involved in this study. A sample size of 30 was calculated. Reading of PI, heart rate, and blood pressures (systolic, diastolic, and mean arterial) were recorded at pre-intubation, post-intubation, during neuromuscular block reversal, pre-extubation and at extubation. Clinically significant heart rate, blood pressure (systolic, diastolic, and mean) and PI was defined as increase by >10 bpm, rise by ≥15 bpm and a decrease by ≥10%, respectively, from pre-intubation value.

Results

Clinically significant change in PI was seen at all intervals with maximum decrease in PI occurring during neuromuscular block reversal (42.6% at the start and 56.7% at the end of neuromuscular block reversal). A negative correlation was noted between PI and the other non-invasive hemodynamic parameters.

Conclusion

PI decreases on noxious stimuli and correlates negatively with the other non-invasive hemodynamic parameters. Hemodynamic response at neuromuscular block reversal is maximum.

Evaluation of perfusion index as an objective tool to assess analgesia during laparoscopic surgeries under general anaesthesia

Background and Aims:

Methods:

Results:

Conclusion:

Assessment of Tissue Perfusion Using the Peripheral Perfusion Index and Lactate Clearance in Shock in Pediatric Patients

BACKGROUND

Pediatric shock has a high mortality rate because many of the early clinical signs are subtle and have poor sensitivity and specificity. Pediatric shock was categorized either: compensated with normal blood pressure, poor skin perfusion (CRT >2 s, mottled, cool peripheries, peripheral cyanosis), weak peripheral pulse, age specific tachycardia, tachypnoea, and oliguria or decompensated with hypotension (SBP < 70 + (2× age in years) mm Hg and decreased mental status. The perfusion index is a non-invasive method for assessing peripheral perfusion and may be a useful marker for identifying shock early in pediatric patients.

OBJECTIVE

This prospective cohort study (November 2019 to August 2020) evaluated whether the perfusion index, lactate, and/or lactate clearance could predict mortality among pediatric shock patients.

METHODS

Fifty children (68% male) with shock underwent assessments at presentation to the emergency room to evaluate their heart rate, blood pressure, capillary refill time, central venous pressure, perfusion index, cardiac index, systemic vascular resistance, central venous oxygen saturation, and lactate clearance.

RESULTS

The perfusion index range was 0.03 to 2.2 and ≤0.18 as the cut-off for mortality prediction providing 74% sensitivity and 78% specificity. The serum lactate concentration range was 0 to 16 mmol/L and >5.7 mmol/L as the cut-off for mortality prediction provided 70% sensitivity and 96% specificity at presentation to the emergency room. The lactate clearance range was 3% to 75% and >10% as the cut-off for survival prediction after resuscitation and at 6 h later.

CONCLUSION

Perfusion index (PI), lactate, and lactate clearance provided comparable sensitivity and specificity for predicting outcomes among pediatric patients with shock Therefore, we suggest that the PI is an inexpensive, rapid, and non-invasive tool that can be used to predict illness severity and mortality in busy pediatric intensive care units and emergency departments. This tool may guide better patient triage and an earlier diagnosis of shock in this setting.

Comparative study of the Ambu® AuraOnce™ laryngeal mask and endotracheal intubation in anesthesia airway management during neurosurgery

Objective

To investigate the feasibility and efficacy of the Ambu® AuraOnce™ laryngeal mask (LMA) compared with endotracheal intubation (ETI) during supratentorial tumor resection in the right lateral decubitus position.

Methods

This was a randomized controlled trial of LMA compared with ETI in patients who were scheduled to undergo supratentorial tumor resection in the right lateral decubitus position. The patients were randomized to the LMA (n = 40) and ETI groups (n = 40). The hemodynamic parameters (primary outcome) and mechanical ventilation parameters, anesthetic dose, and complications as well as quality of anesthesia recovery (secondary outcomes) were compared.

Results

Patients in the LMA group exhibited lower mean arterial pressure (MAP) and heart rate (HR) compared with ETI. Nine and two patients received esmolol during intubation and extubation, respectively. The airway pressure (AP) in the LMA group was higher compared with the ETI group 60 minutes after the start of surgery. Compared with the ETI group, the sufentanil dose was lower by 24% and the anesthesia recovery rate was better in the LMA group.

Conclusions

LMA can improve hemodynamic stability in patients undergoing supratentorial tumor resection in the right lateral decubitus position. If there is a clinical need and no contraindication, LMA could replace ETI.

Prediction of Shock by Peripheral Perfusion Index

OBJECTIVE

To detect occurrence of clinical shock and impending shock by monitoring Peripheral Perfusion Index (PI).

METHODS

In this study, 100 children aged 1 mo to 12 y of age who needed hemodynamic monitoring were included and categorized into five age groups. Demographic data, nutritional status, vital parameters, perfusion index and laboratory parameters were recorded. Hemodynamic monitoring was done for 48 h. In total, 65 and 35 children were admitted with and without features of shock respectively. Nine hundred thirty six hemodynamic measurements were taken and analyzed. Correlation between perfusion index, blood pressures and clinically assessed shock were done.

RESULTS

Clinical shock can be reasonably detected when perfusion index value is less than 1.15 in children less than 3 y of age, less than 1.25 in 3 to 10 y of age and less than 1.55 in 10 to 12 y of age. These values had high sensitivity and low false positivity in detecting clinically assessed shock in that particular age group. PI had good correlation with pulse pressure and systolic blood pressure in all age groups and weak correlation with mean arterial blood pressure and diastolic blood pressure. A 57% reduction in PI value from the baseline value may predict impending shock in children.

CONCLUSION

Perfusion index can be used as a non-invasive, continuous parameter to monitor peripheral perfusion in children and to detect impending shock.

A Comparison between the i-gel® and air-Q® Supraglottic Airway Devices Used for the Patients Undergoing General Anesthesia with Muscle Relaxation

OBJECTIVES

The aim of the present study was to compare two supraglottic airway (SGA) devices (i.e., the i-gel® © Intersurgical Ltd and air-Q® (Reusable) Cookgas company) in terms of the insertion time, amount of leak during ventilation with maximum positive pressure, and postoperative complications in patients referring to Modarres Hospital in Tehran.

METHOD

The present double-blind clinical trial was performed on 60 patients undergoing elective surgeries that required general anesthesia with muscle relaxation. Patients were randomly assigned to either i-gel® (n = 30) or Air-Q® (n = 30) groups.

RESULTS

The mean age, body mass index, duration of surgery, duration of anesthesia, and gender ratio were not significantly different between the two groups. Mean ± SD values of the SGA devices' insertion time (in seconds) in the air-Q® and i-gel® groups were 4.87 ± 1.6 and 6.80 ± 1.2, respectively (P < 0.001). The mean OLP in the Air-Q® group was significantly higher than that of the i-gel® group (35.9 ± 9.6 versus 24.8 ± 3.7, p < 0.001). The frequency of complications occurred after the supraglottic airway insertion was higher in the i-gel® group. However, only in terms of sore throat, the difference between the two groups was statistically significant: 6 (20%) had sore throat (P = 0.024) in the i-gel groups, but in in the Air-Q® groups no one had this side effect after surgery.

CONCLUSION

It was concluded that the Air-Q® supraglottic airway was placed faster and easier with fewer complications than the i-gel in general anesthesia with muscle relaxation. The frequency of the occurrence of all three complications, cough, sore throat, and blood, on the cuff (6 (20%) was higher in the i-gel group than that in the air-Q® group (cough3 (10%), sore throat 0 (0%), and blood on the cuff 3 (10%) (P < 0.05).

Evaluation of perfusion index as a tool for pain assessment in critically ill patients

Pain is a common and undertreated problem in critically ill patients. Pain assessment in critically ill patients is challenging and relies on complex scoring systems. The aim of this work was to find out the possible role of the perfusion index (PI) measured by a pulse oximeter (Masimo Radical 7; Masimo Corp., Irvine, CA, USA) in pain assessment in critically ill patients. A prospective observational study was carried out on 87 sedated non-intubated patients in a surgical intensive care unit. In addition to routine monitoring, a Masimo pulse oximeter probe was used for PI measurement. The sedation level of the patients was assessed by using the Richmond Agitation-Sedation Scale (RASS). The pain intensity was determined by applying the behavioral pain scale for non-intubated (BPS-NI) patients. The PI, arterial blood pressure, heart rate, RASS, and BPS-NI values before and after the application of a standard painful stimulus (changing the patient position) were reported. Correlation between the PI and other variables was carried out at the two measurements. Correlation between changes in the PI (delta PI) and in the hemodynamic variables, RASS, and BPS-NI was also done. Changing the patient position resulted in a significant increase in SBP (128 ± 20 vs 120.4 ± 20.6, P = 0.009), DBP (71.3 ± 11.2 vs 68.7 ± 11.3, P = 0.021), heart rate (99.5 ± 19 vs 92.7 ± 18.2, P = 0.013), and BPS-NI (7[6-8] vs 3[3-3], P < 0.001) values and a significant decrease in the PI (1[0.5-1.9] vs 2.2[0.97-3.6], P < 0.001) value compared to the baseline readings. There was no correlation between the values of the PI and the ABP, BPS-NI, and RASS at the two measurements. A good correlation was found between the delta PI and delta BPS-NI (r = -0.616, P < 0.001). A weak correlation was observed between the PI and heart rate after the patient positioning (r = -0.249, P < 0.02). In surgical critically ill non-intubated patients, the application of a painful stimulus was associated with decreased PI. There was a good correlation between the change in the PI and the change in BPS-NI values after the application of painful stimulus.

Comparison of i-gel™ and laryngeal mask airway Classic™ in terms of ease of insertion and hemodynamic response: A randomized observational study

Context:

Laryngeal mask airway (LMA) Classic™ has an inflatable cuff while i-gel™ has a noninflatable cuff made of thermoplastic elastomer.

Aims:

To compare ease of insertion, number, and duration of insertion attempts among the two device. Secondary objectives were to evaluate the hemodynamic response and SpO₂ during device insertion and during maintenance of general anesthesia.

Settings and Design:

This study was conducted as randomized observational study in a teaching hospital.

Subjects and Methods:

One hundred American Society of Anesthesiologists I and II, patients posted for surgery under general anesthesia were divided in two groups of fifty each. LMA Classic™ and i-gel™. Ease of insertion, duration of insertion, hemodynamic data, and episodes of hypoxia during insertion, 1, 3 and 5 min for 30 min, during removal and 1 min after removal.

Statistical Analysis Used:

Descriptive analyses were expressed as a mean ± standard deviation. Independent t-test used for parametric data, Chi-square test for nonparametric data and hemodynamic data were analyzed using repeated measures ANOVA to find statistical difference within the groups.

Results:

Devices were easy to insert, the mean duration of insertion attempts was 15.92 ± 1.62 s in the i-gel™ group, while it was 26.06 ± 5.12 s in the LMA Classic™ group, was statistically significant (P = 0.0001).

Conclusions:

Successful and shorter duration of insertion, with less hemodynamic response makes i-gel™ a suitable alternative to LMA Classic™ during general anesthesia.

Better Hemodynamic Profile of Laryngeal Mask Airway Insertion Compared to Laryngoscopy and Tracheal Intubation

Background:

Laryngoscopy and tracheal intubation can cause serious cardiovascular responses in patients such as hypertension, tachycardia, and arrhythmias. Alternative airway maintenance techniques may attenuate these hemodynamic stress responses.

Objectives:

This study aimed to compare the immediate hemodynamic effects of the insertion of laryngeal mask airway supreme (LMA-S) and classic (LMA-C) with laryngoscopy and Endotracheal Intubation (ETT).

Patients and Methods:

This study was a prospective, double-blind, and randomized clinical trial conducted on 150 patients aged 18 to 50 years with ASA I (American Society of Anesthesiologists), in the general operating room of Shahid Mohammadi hospital, Hormozgan university of medical sciences, Bandar Abbas, Iran. In the ETT group, endotracheal intubation was performed using the Macintosh laryngoscope; while for the LMA-C and LMA-S groups, LMA Classic and LMA Supreme were inserted, respectively. The induction and maintenance of anesthesia were similar in all patients. The hemodynamic parameters such as heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were measured before (baseline) and after induction of anesthesia at 4 different time points. The statistical analysis was done and P value less than 0.05 was considered significant.

Results:

Participants in all groups were similar in terms of gender, age, weight, height, and Mallampati class. The mean ± SD of SBPs (105.62 ± 12.12, 112.90 ± 12.2, and 112.48 ± 15.14 mm Hg, respectively for ETT, LMA-C, and LMA-S) and DBPs (64.64 ± 10.23, 73.78 ± 9.70, and 71.20 ± 12.27 mm Hg, respectively for ETT, LMA-C, and LMA-S) were significantly lower in the ETT group compared to LMA groups 5 minutes after device insertion (P < 0.01 for SBPs and P < 0.001 for DBPs); however these values were lower than the baseline values in all groups. There were no differences in the mean SBP and DBPs between the three groups at the other time points. The mean ± SD heart rates in the ETT group, compared to the LMA-C and LMA-S groups, were considerably higher in the first minute (100.06 ± 18.27, 82.50 ± 10.52, and 82.00 ± 13.60 bpm, respectively for ETT, LMA-C, and LMA-S), third minute (91.04 ± 17.12, 78.84 ± 11.23, and 78.90 ± 13.41 bpm, respectively for ETT, LMA-C, and LMA-S) and fifth minute (85.82 ± 16.01, 75.78 ± 11.73, and 75.04 ± 13.90 bpm, respectively for ETT, LMA-C, and LMA-S) after intubation (P < 0.001). There were no significant differences between the LMA-C and LMA-S groups in terms of hemodynamic parameters.

Conclusions:

Maintaining the airway using laryngeal mask airway is associated with less cardiovascular responses compared to direct laryngoscopy and tracheal intubation.

Perfusion index derived from a pulse oximeter can detect changes in peripheral microcirculation during uretero-renal-scopy stone manipulation (URS-SM)

Background

The objective of this study was to test the effect of removal of a ureteral obstruction (renal calculus) from anesthetized patients on the perfusion index (PI), as measured by a pulse oximeter, and on the estimated glomerular filtration rate (eGFR).

Patients and Methods

This prospective study enrolled 113 patients with unilateral ureteral obstructions (kidney stones) who were scheduled for ureteroscopy (URS) laser lithotripsy. One urologist graded patient hydronephrosis before surgery. A pulse oximeter was affixed to each patient's index finger ipsilateral to the intravenous catheter, and a non-invasive blood pressure cuff was placed on the contralateral side. Ipsilateral double J stents and Foley catheters were inserted and left indwelling for 24 h. PI and mean arterial pressure (MAP) were determined at baseline, 5 min after anesthesia, and 10 min after surgery; eGFR was determined at admission, 1 day after surgery, and 14 days after surgery.

Results

Patients with different grades of hydronephrosis had similar age, eGFR, PI, mean arterial pressure (MAP), and heart rate (HR). PI increased significantly in each hydronephrosis group after ureteral stone disintegration. None of the groups had significant post-URS changes in eGFR, although eGFR increased in the grade I hydronephrosis group after 14 days. The percent change of PI correlates significantly with the percent change of MAP, but not with that of eGFR.

Conclusion

Our results demonstrate that release of a ureteral obstruction leads to a concurrent increase of PI during anesthesia. Measurement of PI may be a valuable tool to monitor the successful release of ureteral obstructions and changes of microcirculation during surgery. There were also increases in eGFR after 14 days, but not immediately after surgery.