Blood pressure and heart rate changes during intubation: a comparison of direct laryngoscopy and a fibreoptic method

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.

Dose and cardiopulmonary effects of propofol alone or with midazolam for induction of anesthesia in critically ill dogs

OBJECTIVE

To determine the dose and cardiopulmonary effects of propofol alone or with midazolam for induction of anesthesia in American Society of Anesthesiologists status ≥III dogs requiring emergency abdominal surgery.

STUDY DESIGN

Prospective, randomized, blinded, clinical trial.

ANIMALS

A total of 19 client-owned dogs.

METHODS

Dogs were sedated with fentanyl (2 μg kg^-1) intravenously (IV) for instrumentation for measurement of heart rate, arterial blood pressure, cardiac index, systemic vascular resistance index, arterial blood gases, respiratory rate and rectal temperature. After additional IV fentanyl (3 μg kg^-1), the quality of sedation was scored and cardiopulmonary variables recorded. Induction of anesthesia was with IV propofol (1 mg kg^-1) and saline (0.06 mL kg^-1; group PS; nine dogs) or midazolam (0.3 mg kg^-1; group PM; 10 dogs), with additional propofol (0.25 mg kg^-1) IV every 6 seconds until endotracheal intubation. Induction/intubation quality was scored, and anesthesia was maintained with isoflurane. Variables were recorded for 5 minutes with the dog in lateral recumbency, breathing spontaneously, and then in dorsal recumbency with mechanical ventilation for the next 15 minutes. A general linear mixed model was used with post hoc analysis for multiple comparisons between groups (p < 0.05).

RESULTS

There were no differences in group demographics, temperature and cardiopulmonary variables between groups or within groups before or after induction. The propofol doses for induction of anesthesia were significantly different between groups, 1.9 ± 0.5 and 1.1 ± 0.5 mg kg^-1 for groups PS and PM, respectively, and the induction/intubation score was significantly better for group PM.

CONCLUSIONS AND CLINICAL RELEVANCE

Midazolam co-induction reduced the propofol induction dose and improved the quality of induction in critically ill dogs without an improvement in cardiopulmonary variables, when compared with a higher dose of propofol alone.

Fibreoptic intubation in airway management: a review article

Since the first use of the flexible fibreoptic bronchoscope, a plethora of new airway equipment has become available. It is essential for clinicians to understand the role and limitations of the available equipment to make appropriate choices. The recent 4th National Audit Project conducted in the United Kingdom found that poor judgement with inappropriate choice of equipment was a contributory factor in airway morbidity and mortality. Given the many modern airway adjuncts that are available, we aimed to define the role of flexible fibreoptic intubation in decision-making and management of anticipated and unanticipated difficult airways. We also reviewed the recent literature regarding the role of flexible fibreoptic intubation in specific patient groups who may present with difficult intubation, and concluded that the flexible fibrescope maintains its important role in difficult airway management.

Rapid Sequence Intubation in Traumatic Brain-injured Adults

Deciding on proper medication administration for the traumatic brain injury (TBI) patient undergoing intubation can be daunting and confusing. Pretreatment with lidocaine and/or vecuronium is no longer recommended; however, high-dose fentanyl can be utilized to help blunt the sympathetic stimulation of intubation. Induction with etomidate is recommended; however, ketamine can be considered in the proper patient population, such as those with hypotension. Paralysis can be performed with either succinylcholine or rocuronium, with the caveat that rocuronium can lead to delays in proper neurological examinations due to prolonged paralysis. Recommendations for post-intubation continuous sedation medications include a combination propofol and fentanyl in the normotensive/hypertensive patient population. A combination midazolam and fentanyl or ketamine alone can be considered in the hypotensive patient.

Less postoperative sore throat after nasotracheal intubation using a fiberoptic bronchoscope than using a Macintosh laryngoscope: A double-blind, randomized, controlled study

STUDY OBJECTIVE

To evaluate whether nasotracheal intubation using a fiberoptic bronchoscope reduces postoperative sore throat.

DESIGN

Prospective, double-blinded, randomized, and controlled study.

SETTING

Postoperative areas and surgical ward of a university hospital.

PATIENTS

Seventy-four patients with American Society of Anesthesiologists physical status I-II who were scheduled for elective general anesthesia requiring nasotracheal intubation.

INTERVENTIONS

Patients were randomized to one of two intubation groups, F (fiberoptic bronchoscope-guided) and M (Macintosh laryngoscope-guided), and after induction of general anesthesia, the patients' tracheas were intubated via the nose.

MEASUREMENTS

The intensity of postoperative sore throat was evaluated using a numerical rating score (0=none, 10=severe) at 24 hours postoperatively, and the incidence of nasal mucosal trauma, time to completion of intubation, and hemodynamic responses were recorded and compared between groups.

MAIN RESULTS

The numerical rating score value was significantly lower in group F than in group M (P=.0047), but the incidence of nasal mucosal trauma was comparable between the two groups. The median time to completion of intubation was shorter for group F than group M (P<.0001). Hemodynamic responses were not significantly different.

CONCLUSIONS

Fiberoptic bronchoscope-guided intubation is associated with less sore throat after nasotracheal intubation than M intubation. The time to completion of intubation was significantly shorter using the fiberoptic bronchoscope than that using the Macintosh laryngoscope.

Effects of lidocaine and magnesium sulfate in attenuating hemodynamic response to tracheal intubation: single-center, prospective, double-blind, randomized study

BACKGROUND AND OBJECTIVES

Hemodynamic response to airway stimuli is a common phenomenon and its management is important to reduce the systemic repercussions. The objective of this study is to compare the efficacy of intravenous magnesium sulfate versus lidocaine on this reflex hemodynamics after laryngoscopy and tracheal intubation.

METHODS

This single-center, prospective, double-blind, randomized study evaluated 56 patients ASA 1 or 2, aged 18-65 years, scheduled for elective surgeries under general anesthesia with intubation. The patients were allocated into two groups: Group F received 30mg·kg^-1 of magnesium sulphate and Group L, 2mg·kg^-1 of lidocaine, continuous infusion, immediately before the anesthetic induction. Blood pressure (BP), heart rate (HR), and bispectral index (BIS) were measured in both groups at six different times related to administration of the study drugs.

RESULTS

In both groups there was an increase in HR and BP after laryngoscopy and intubation, compared to baseline. Group M showed statistically significant increase in the values of systolic and diastolic blood pressure after intubation, which was clinically unimportant. There was no difference in the BIS values between groups. Among patients receiving magnesium sulfate, three (12%) had high blood pressure versus only one among those receiving lidocaine (4%), with no statistical difference.

CONCLUSION

Magnesium sulfate and lidocaine have good efficacy and safety for hemodynamic management in laryngoscopy and intubation.

[Effects of lidocaine and magnesium sulfate in attenuating hemodynamic response to tracheal intubation: single-center, prospective, double-blind, randomized study]

BACKGROUND AND OBJECTIVES

Hemodynamic response to airway stimuli is a common phenomenon and its management is important to reduce the systemic repercussions. The objective of this study is to compare the efficacy of intravenous magnesium sulfate versus lidocaine on this reflex hemodynamics after laryngoscopy and tracheal intubation.

METHODS

This single-center, prospective, double-blind, randomized study evaluated 56 patients ASA 1 or 2, aged 18 to 65 years, scheduled for elective surgeries under general anesthesia with intubation. The patients were allocated into two groups: Group F received 30mg·kg^-1 of magnesium sulphate and Group L, 2mg·kg^-1 of lidocaine, continuous infusion, immediately before the anesthetic induction. Blood pressure (BP), heart rate (HR), and bispectral index (BIS) were measured in both groups at six different times related to administration of the study drugs.

RESULTS

In both groups there was an increase in HR and BP after laryngoscopy and intubation, compared to baseline. Group M showed statistically significant increase in the values of systolic and diastolic blood pressure after intubation, which was clinically unimportant. There was no difference in the BIS values between groups. Among patients receiving magnesium sulfate, three (12%) had high blood pressure versus only one among those receiving lidocaine (4%), with no statistical difference.

CONCLUSION

Magnesium sulfate and lidocaine have good efficacy and safety for hemodynamic management in laryngoscopy and intubation.

A study of stress response to endotracheal intubation comparing glidescope and flexible fiberoptic bronchoscope

OBJECTIVE

To compare hemodynamic stress response (HDSR) to ET intubation using Glidescope (GLS) and Flexible fiberoptic laryngoscope (FFB).

METHODS

This prospective randomized comparative study was conducted at King Khalid University Hospital, King Saud University, Riyadh, Saudi Arabia from June 2011 - November 2013. Eighty ASA 1 & 2 patients with normal airway undergoing elective surgical procedure requiring ET intubation were included in the study. Patients were randomly assigned in two groups GLS or FFB. General anesthesia was induced with propofol and fentanyl. Muscle relaxation was achieved with cisatracurium and ET intubation was performed using either GLS or FFB. Noninvasive hemodynamic data was recorded (HR, systolic, diastolic and mean blood pressure) as pre-induction, baseline and after ET intubation at one minute intervals for successive five minutes. End tidal Sevoflurane and CO2 at the time of intubation, need of external neck pressure, time to successful intubation and number of attempts were recorded; and rate pressure product was calculated.

RESULTS

Induction of anesthesia resulted in significant fall in blood pressure in both the groups. ET intubation resulted in similar rise of BP in both groups (for 3-4 minutes) from their baseline values; however the rise was not significantly different from their respective pre-induction values. Time to intubation was longer with FFB compared to GLS however, need for external neck manipulation was more with GLS.

CONCLUSION

There was no difference in HDSR due to ET intubation using either GLS or FFB in healthy adult patients with normal airway. Rate pressure product remained within the acceptable range.

Hemodynamic responses to tracheal intubation with the Glidescope videolaryngoscope: a comparison of oral and nasal routes

BACKGROUND

Although there have been numerous favorable reports on the uses of the GlideScope videolaryngoscope (GSVL) in oral and nasal intubations, no study has compared the hemodynamic responses to oral and nasal intubations with the GSVL in a single clinical trial. The purpose of this randomized clinical study was to determine whether there was a clinically relevant difference between the hemodynamic responses to oral and nasal intubations with the GSVL.

METHODS

A total of 71 patients, ASA physical status I, aged 18-50 years, scheduled for elective plastic surgery under general anesthesia, were randomly allocated to the oral intubation group (OI group) and the nasal intubation group (NI group). Noninvasive blood pressure (BP) and heart rate (HR) were recorded before (baseline values) and after anesthesia induction (postinduction values), at intubation and every minute for a further 5 minutes. Maximum values of BP and HR during the observation were noted. The product of HR and systolic blood pressure (rate pressure product, RPP), the percent changes of systolic blood pressure (SBP) and HR relative to the baseline values at every measuring point, and the areas under the SBP and HR versus time curves were calculated.

RESULTS

The intubation time was significantly longer in the NI group than in the OI group. The total incidence of difficulties encountered during laryngoscopy and intubation were higher in the OI group than in the NI group (29% vs. 6%, p < 0.05). BP at all measuring points, the maximum values of BP, the area under the SBP versus time curve, and the incidence of SBP percent increase more than 30% of baseline value did not differ significantly between the two groups. However, HR and RPP at intubation and their maximum values during the observation, the area under the HR versus time curve, and the incidence of HR percent increase more than 30% of baseline value were significantly higher in the OI group than in the NI group (p < 0.05). As compared with the NI group, the times required to reach the maximum values of SBP and HR were significantly shorter and the times required for recovery of SBP and HR to postinduction values were significantly longer in the OI group (p < 0.05).

CONCLUSION

In anesthetized adult patients, oral and nasal intubations with the GSVL can result in a similar pressor response. However, the tachycardic response to nasal intubation using a GSVL is smaller and of shorter duration than that to oral intubation using a GSVL.