Rate of Decline in Oxygen Saturation at Various Pulse Oximetry Values with Prehospital Rapid Sequence Intubation

A Descriptive Analysis of Air Medical Pediatric Rapid Sequence Intubation: Successes and Opportunities

OBJECTIVE

Advanced airway management, including the use of rapid sequence intubation (RSI), is fundamental in resuscitation. However, the reported experience with pediatric airway management is limited because of the relatively low number of emergency RSI procedures in children. The aim of this study was to document the experience with pediatric RSI in a large air medical database and explore opportunities for improvement.

METHODS

All pediatric patients (age < 18 years) undergoing RSI by air medical crews between 2015 and 2019 were included in this analysis. Subjects were divided a priori into 3 age subgroups (0-2 years, 3-8 years, and 9-17 years). The primary variables of interest included overall intubation success, first-attempt intubation success, and first-attempt intubation success without desaturation. The rates of positive-pressure ventilation (PPV) use for preoxygenation and oxygen desaturation were also explored.

RESULTS

A total of 1,091 pediatric RSI patients were included. The overall intubation success rate was 98% (0-2 years = 96%, 3-8 years = 97%, and 9-17 years = 98%), with 91% intubated on the first attempt (0-2 years = 86%, 3-8 years = 90%, and 9-17 years = 92%) and 87% intubated on the first attempt without oxygen desaturation (0-2 years = 80%, 3-8 years = 88%, and 9-17 years = 90%). A sharp decline in intubation success was observed with preoxygenation SpO2 values < 97% across all patients. Younger patients (0-2 years) had lower initial SpO2 values and decreased first-attempt success rates with and without desaturation. These patients were less likely to receive PPV during preoxygenation attempts and had lower use of video laryngoscopy or a bougie on the initial intubation attempt.

CONCLUSION

In this study, we documented high success rates for air medical pediatric RSI. Higher target SpO2 values may be justified during preoxygenation. Intubation success, PPV use for preoxygenation, video laryngoscopy, and the use of a bougie were lower for younger patients.

Oxygenation during the apnoeic phase preceding intubation in adults in prehospital, emergency department, intensive care and operating theatre environments

BACKGROUND

Apnoeic oxygenation is the delivery of oxygen during the apnoeic phase preceding intubation. It is used to prevent respiratory complications of endotracheal intubation that have the potential to lead to significant adverse events including dysrhythmia, haemodynamic decompensation, hypoxic brain injury and death. Oxygen delivered by nasal cannulae during the apnoeic phase of intubation (apnoeic oxygenation) may serve as a non-invasive adjunct to endotracheal intubation to decrease the incidence of hypoxaemia, morbidity and mortality.

OBJECTIVES

To evaluate the benefits and harms of apnoeic oxygenation before intubation in adults in the prehospital, emergency department, intensive care unit and operating theatre environments compared to no apnoeic oxygenation during intubation.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 4 November 2022.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and quasi-RCTs that compared the use of any form of apnoeic oxygenation including high flow and low flow nasal cannulae versus no apnoeic oxygenation during intubation. We defined quasi-randomization as participant allocation to each arm by means that were not truly random, such as alternation, case record number or date of birth. We excluded comparative prospective cohort and comparative retrospective cohort studies, physiological modelling studies and case reports.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were 1. hospital stay and 2. incidence of severe hypoxaemia. Our secondary outcomes were 3. incidence of hypoxaemia, 4. lowest recorded saturation of pulse oximetry (SpO2), 5. intensive care unit (ICU) stay, 6. first pass success rate, 7. adverse events and 8.

MORTALITY

We used GRADE to assess certainty of evidence.

MAIN RESULTS

We included 23 RCTs (2264 participants) in our analyses. Eight studies (729 participants) investigated the use of low-flow (15 L/minute or less), and 15 studies (1535 participants) investigated the use of high-flow (greater than 15 L/minute) oxygen. Settings were varied and included the emergency department (2 studies, 327 participants), ICU (7 studies, 913 participants) and operating theatre (14 studies, 1024 participants). We considered two studies to be at low risk of bias across all domains. None of the studies reported on hospital length of stay. In predominately critically ill people, there may be little to no difference in the incidence of severe hypoxaemia (SpO2 less than 80%) when using apnoeic oxygenation at any flow rate from the start of apnoea until successful intubation (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.66 to 1.11; P = 0.25, I² = 0%; 15 studies, 1802 participants; low-certainty evidence). There was insufficient evidence of any effect on the incidence of hypoxaemia (SpO2 less than 93%) (RR 0.58, 95% CI 0.23 to 1.46; P = 0.25, I² = 36%; 3 studies, 489 participants; low-certainty evidence). There may be an improvement in the lowest recorded oxygen saturation, with a mean increase of 1.9% (95% CI 0.75% to 3.05%; P < 0.001, I² = 86%; 15 studies, 1525 participants; low-certainty evidence). There may be a reduction in the duration of ICU stay with the use of apnoeic oxygenation during intubation (mean difference (MD) ‒1.13 days, 95% CI ‒1.51 to ‒0.74; P < 0.0001, I² = 46%; 5 studies, 815 participants; low-certainty evidence). There may be little to no difference in first pass success rate (RR 1.00, 95% CI 0.93 to 1.08; P = 0.79, I² = 0%; 8 studies, 826 participants; moderate-certainty evidence). There may be little to no difference in incidence of adverse events including oral trauma, arrhythmia, aspiration, hypotension, pneumonia and cardiac arrest when apnoeic oxygenation is used. There was insufficient evidence about any effect on mortality (RR 0.84, 95% CI 0.70 to 1.00; P = 0.06, I² = 0%; 6 studies, 1015 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

There was some evidence that oxygenation during the apnoeic phase of intubation may improve the lowest recorded oxygen saturation. However, the differences in oxygen saturation were unlikely to be clinically significant. This did not translate into any measurable effect on the incidence of hypoxaemia or severe hypoxaemia in a group of predominately critically ill people. We were unable to assess the influence on hospital length of stay; however, there was a reduction in ICU stay in the apnoeic oxygenation group. The mechanism for this is unclear as there was little to no difference in first pass success or adverse event rates.

Pharmacotherapy optimization for rapid sequence intubation in the emergency department

PURPOSE

Rapid-sequence intubation (RSI) is the process of administering a sedative and neuromuscular blocking agent (NMBA) in rapid succession to facilitate endotracheal intubation. It is the most common and preferred method for intubation of patients presenting to the emergency department (ED). The selection and use of medications to facilitate RSI is critical for success. The purpose of this review is to describe pharmacotherapies used during the RSI process, discuss current clinical controversies in RSI medication selection, and review pharmacotherapy considerations for alternative intubation methods.

SUMMARY

There are several steps to the intubation process requiring medication considerations, including pretreatment, induction, paralysis, and post-intubation sedation and analgesia. Pretreatment medications include atropine, lidocaine, and fentanyl; but use of these agents in clinical practice has fallen out of favor as there is limited evidence for their use outside of select clinical scenarios. There are several options for induction agents, though etomidate and ketamine are the most used due to their more favorable hemodynamic profiles. Currently there is retrospective evidence that etomidate may produce less hypotension than ketamine in patients presenting with shock or sepsis. Succinylcholine and rocuronium are the preferred neuromuscular blocking agents, and the literature suggests minimal differences between succinylcholine and high dose rocuronium in first-pass success rates. Selection between the two is based on patient specific factors, half-life and adverse effect profiles. Finally, medication-assisted preoxygenation and awake intubation are less common methods for intubation in the ED but require different considerations for medication use.

AREAS FOR FUTURE RESEARCH

The optimal selection, dosing, and administration of RSI medications is complicated, and further research is needed in several areas. Additional prospective studies are needed to determine optimal induction agent selection and dosing in patients presenting with shock or sepsis. Controversy exists over optimal medication administration order (paralytic first vs induction first) and medication dosing in obese patients, but there is insufficient evidence to significantly alter current practices regarding medication dosing and administration. Further research examining awareness with paralysis during RSI is needed before definitive and widespread practice changes to medication use during RSI can be made.

Airway registries in primarily adult, emergent endotracheal intubation: a scoping review

BACKGROUND

Emergency Department (ED) airway registries are formalized methods to collect and document airway practices and outcomes. Airway registries have become increasingly common in EDs globally; yet there is no consensus of airway registry methodology or intended utility. This review builds on previous literature and aims to provide a thorough description of international ED airway registries and discuss how airway registry data is utilized.

METHODS

A search of Medline, Embase, Scopus, Cochrane Libraries, Web of Science, and Google Scholar was performed with no date limitations applied. English language full-text publications and grey literature from centres implementing an ongoing airway registry to monitor intubations performed in mainly adult patients in an ED setting were included. Non-English publications and publications describing airway registries to monitor intubation practices in predominantly paediatric patients or settings outside of the ED were excluded. Study screening for eligibility was performed by two team members individually, with any disagreements resolved by a third team member. Data was charted using a standardized data charting tool created for this review.

RESULTS

Our review identified 124 eligible studies from 22 airway registries with a global distribution. We found that airway registry data is used for quality assurance, quality improvement, and clinical research regarding intubation practices and contextual factors. This review also demonstrates that there is a great deal of heterogeneity in definitions of first-pass success and adverse events in the peri-intubation period.

CONCLUSIONS

Airway registries are used as a crucial tool to monitor and improve intubation performance and patient care. ED airway registries inform and document the efficacy of quality improvement initiatives to improve intubation performance in EDs globally. Standardized definitions of first-pass success and peri-intubation adverse events, such as hypotension and hypoxia, may allow for airway management performance to be compared on a more equivalent basis and allow for the development of more reliable international benchmarks for first-pass success and rates of adverse events in the future.

Non-invasive ventilation for preoxygenation before general anesthesia: a systematic review and meta-analysis of randomized controlled trials

Background and objectives

Preoxygenation is crucial for providing sufficient oxygen reservoir to a patient before intubation and enables the extension of the period between breathing termination and critical desaturation (safe apnoea time). Conventionally, face mask ventilation is used for preoxygenation. Non-invasive ventilation is a new preoxygenation method. The study objective was to compare the outcomes of non-invasive ventilation and face mask ventilation for preoxygenation.

Method

PubMed, Embase, Cochrane Library, and the ClinicalTrials.gov registry were searched for eligible studies published from database inception to September 2021. Individual effect sizes were standardized, and a meta-analysis was conducted using random effects models to calculate the pooled effect size. Inclusion criteria were randomised controlled trials of comparing the outcomes of non-invasive ventilation or face mask ventilation for preoxygenation in patients scheduled for surgeries. The primary outcome was safe apnea time, and the secondary outcomes were post-operative complications, number of patients who achieved the expired O₂ fraction (FeO₂) after 3 min of preoxygenation, minimal SpO₂ during tracheal intubation, partial pressure of oxygen in the arterial blood (PaO₂) and partial pressure of carbon dioxide (PaCO₂) after preoxygenation, and PaO₂ and PaCO₂ after tracheal intubation.

Results

13 trials were eligible for inclusion in this study. Significant differences were observed in safe apnoea time, number of patients who achieved FeO₂ 90% after preoxygenation for 3 min, and PaO₂ and PaCO₂ after preoxygenation and tracheal intubation. Only in the non-obese subgroup, no significant difference was observed in safe apnoea time (mean difference: 125.38, 95% confidence interval: − 12.26 to 263.03).

Conclusion

Non-invasive ventilation appeared to be more effective than conventional methods for preoxygenation. We recommend non-invasive ventilation based on our results.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01842-y.

Awake craniotomy using a high-flow nasal cannula with oxygen reserve index monitoring - A report of two cases

BACKGROUND

Awake craniotomy is a well-tolerated procedure for the resection of brain tumors residing within or close to the eloquent cortical areas. Monitored anesthesia care (MAC) is a dominant anesthetic approach for awake craniotomy; however, it is associated with inherent challenges such as desaturation and hypercapnia, which may lead to various complications. The prevention of respiratory insufficiency is important for successful awake craniotomy. As measures to avoid respiratory depression, the use of high-flow nasal cannula (HFNC) can improve patient oxygenation and monitor the monitoring the oxygen reserve index (ORi) can detect hypoxia earlier.

CASE

We report two cases of awake craniotomy with MAC using HFNC and ORi. We adjusted the fraction of inspired oxygen of the HFNC according to the ORi level. The patient underwent successful awake craniotomy without a desaturation event or additional airway intervention.

CONCLUSIONS

Combined HFNC and ORi monitoring may provide adequate oxygen reserves in patients undergoing awake craniotomy.

Optimizing Physiology During Prehospital Airway Management: An NAEMSP Position Statement and Resource Document

Airway management is a critical component of resuscitation but also carries the potential to disrupt perfusion, oxygenation, and ventilation as a consequence of airway insertion efforts, the use of medications, and the conversion to positive-pressure ventilation. NAEMSP recommends:Airway management should be approached as an organized system of care, incorporating principles of teamwork and operational awareness.EMS clinicians should prevent or correct hypoxemia and hypotension prior to advanced airway insertion attempts.Continuous physiological monitoring must be used during airway management to guide the timing of, limit the duration of, and inform decision making during advanced airway insertion attempts.Initial and ongoing confirmation of advanced airway placement must be performed using waveform capnography. Airway devices must be secured using a reliable method.Perfusion, oxygenation, and ventilation should be optimized before, during, and after advanced airway insertion.To mitigate aspiration after advanced airway insertion, EMS clinicians should consider placing a patient in a semi-upright position.When appropriate, patients undergoing advanced airway placement should receive suitable pharmacologic anxiolysis, amnesia, and analgesia. In select cases, the use of neuromuscular blocking agents may be appropriate.

Oxygen Reserve Index: Utility as an Early Warning for Desaturation in High-Risk Surgical Patients

BACKGROUND

Perioperative pulse oximetry hemoglobin saturation (Spo2) measurement is associated with fewer desaturation and hypoxia episodes. However, the sigmoidal nature of oxygen-hemoglobin dissociation limits the accuracy of estimation of the partial pressure of oxygen (Pao2) >80 mm Hg and correspondingly limits the ability to identify when Pao2 >80 mm Hg but falling. We hypothesized that a proxy measurement for oxygen saturation (Oxygen Reserve Index [ORI]) derived from multiwavelength pulse oximetry may allow additional warning time before critical desaturation or hypoxia. To test our hypothesis, we used a Masimo multiwavelength pulse oximeter to compare ORI and Spo2 warning times during apnea in high-risk surgical patients undergoing cardiac surgery.

METHODS

This institutional review board-approved prospective study (NCT03021473) enrolled American Society of Anesthesiologists physical status III or IV patients scheduled for elective surgery with planned preinduction arterial catheter placement. In addition to standard monitors, an ORI sensor was placed and patients were monitored with a pulse oximeter displaying the ORI, a nondimensional parameter that ranges from 0 to 1. Patients were then preoxygenated until ORI plateaued. Following induction of anesthesia, mask ventilation with 100% oxygen was performed until neuromuscular blockade was established. Endotracheal intubation was accomplished using videolaryngoscopy to confirm placement. The endotracheal tube was not connected to the breathing circuit, and patients were allowed to be apneic. Ventilation was resumed when Spo2 reached 94%. We defined ORI warning time as the time from when the ORI alarm registered (based on the absolute value and the rate of change) until the Spo2 decreased to 94%. We defined the Spo2 warning time as the time for Spo2 to decrease from 97% to 94%. The added warning time provided by ORI was defined as the difference between ORI warning time and Spo2 warning time.

RESULTS

Forty subjects were enrolled. Complete data for analysis were available from 37 patients. The ORI alarm registered before Spo2 decreasing to 97% in all patients. Median (interquartile range [IQR]) ORI warning time was 80.4 seconds (59.7-105.9 seconds). Median (IQR) Spo2 warning time was 29.0 seconds (20.5-41.0 seconds). The added warning time provided by ORI was 48.4 seconds (95% confidence interval [CI], 40.4-62.0 seconds; P < .0001).

CONCLUSIONS

In adult high-risk surgical patients, ORI provided clinically relevant added warning time of impending desaturation compared to Spo2. This additional time may allow modification of airway management, earlier calls for help, or assistance from other providers. The potential patient safety impact of such monitoring requires further study.

Oxygenation strategies prior to and during prehospital emergency anaesthesia in UK HEMS practice (PREOXY survey)

Background

Maintaining effective oxygenation throughout the process of Pre-Hospital Emergency Anaesthesia (PHEA) is critical. There are multiple strategies available to clinicians to oxygenate patients both prior to and during PHEA. The optimal pre-oxygenation technique remains unclear, and it is unknown what techniques are being used by United Kingdom Helicopter Emergency Medical Services (HEMS). This study aimed to determine the current pre- and peri-PHEA oxygenation strategies used by UK HEMS services.

Methods

An electronic questionnaire survey was delivered to all UK HEMS services between 05 July and 26 December 2019. Questions investigated service standard operating procedures (SOPs) and individual clinician practice regarding oxygenation strategies prior to airway instrumentation (pre-oxygenation) and oxygenation strategies during airway instrumentation (apnoeic oxygenation). Service SOPs were obtained to corroborate questionnaire replies.

Results

Replies were received from all UK HEMS services (n = 21) and 40 individual clinicians. All services specified oxygenation strategies within their PHEA/RSI SOP and most referred to pre-oxygenation as mandatory (81%), whilst apnoeic oxygenation was mandatory in eight (38%) SOPs. The most commonly identified pre-oxygenation strategies were bag-valve-mask without PEEP (95%), non-rebreathable face mask (81%), and nasal cannula at high flow (81%). Seven (33%) services used Mapleson C circuits, whilst there were eight services (38%) that did not carry bag-valve-masks with PEEP valve nor Mapleson C circuits. All clinicians frequently used pre-oxygenation, however there was variability in clinician use of apnoeic oxygenation by nasal cannula. Nearly all clinicians (95%) reported manually ventilating patients during the apnoeic phase, with over half (58%) stating this was their routine practice. Differences in clinician pre-hospital and in-hospital practice related to availability of humidified high flow nasal oxygenation and Mapleson C circuits.

Conclusions

Pre-oxygenation is universal amongst UK HEMS services and is most frequently delivered by bag-valve-mask without PEEP or non-rebreathable face masks, whereas apnoeic oxygenation by nasal cannula is highly variable. Multiple services carry Mapleson C circuits, however many services are unable to deliver PEEP due to the equipment they carry. Clinicians are regularly manually ventilating patients during the apnoeic phase of PHEA. The identified variability in clinical practice may indicate uncertainty and further research is warranted to assess the impact of different strategies on clinical outcomes.

Oxygen reserve index, a new method of monitoring oxygenation status: what do we need to know?

The oxygen reserve index (ORI) is a new technology that provides real-time, non-invasive, and continuous monitoring of patients’ oxygenation status. This review aimed to discuss its clinical utility, prospect and limitations. A systematic literature search of PubMed, MEDLINE, Google Scholar, and ScienceDirect was performed with the keywords of “oxygen reserve index,” “ORI,” “oxygenation,” “pulse oximetry,” “monitoring,” and “hyperoxia.” Original articles, reviews, case reports, and other relevant articles were reviewed. All articles on ORI were selected. ORI can provide an early warning before saturation begins to decrease and expands the ability to monitor the human body's oxygenation status noninvasively and continuously with the combination of pulse oximetry so as to avoid unnecessary hyperoxia or unanticipated hypoxia. Although the technology is so new that it is rarely known and has not been applied to routine practices in hospitals, it shows good prospects for critical care, oxygen therapy, and intraoperative monitoring.

Study of early warning for desaturation provided by Oxygen Reserve Index in obese patients

Acute hemoglobin desaturation can reflect rapidly decreasing PaO₂. Pulse oximetry saturation (SpO₂) facilitates hypoxia detection but may not significantly decrease until PaO₂ < 80 mmHg. The Oxygen Reserve Index (ORI) is a unitless index that correlates with moderately hyperoxic PaO₂. This study evaluated whether ORI provides added arterial desaturation warning in obese patients. This IRB approved, prospective, observational study obtained written informed consent from Obese (body mass index (BMI) kg m^-2; 30 < BMI < 40) and Normal BMI (19 < BMI < 25) adult patients scheduled for elective surgery requiring general endotracheal anesthesia. Standard monitors and an ORI sensor were placed. Patient's lungs were pre-oxygenated with 100% FiO₂. After ORI plateaued, general anesthesia was induced, and endotracheal intubation accomplished using a videolaryngoscope. Patients remained apneic until SpO₂reached 94%. ORI and SpO₂ were recorded continuously. Added warning time was defined as the difference between the time to SpO₂ 94% from ORI alarm start or from SpO₂ 97%. Data are reported as median; 95% confidence interval. Complete data were collected in 36 Obese and 36 Normal BMI patients. ORI warning time was always longer than SpO₂ warning time. Added warning time provided by ORI was 46.5 (36.0-59.0) seconds in Obese and 87.0 (77.0-109.0) seconds in Normal BMI patients, and was shorter in Obese than Normal BMI patients difference 54.0 (38.0-74.0) seconds (p < 0.0001). ORI provided what was felt to be clinically significant added warning time of arterial desaturation compared to SpO₂. This added time might allow earlier calls for help, assistance from other providers, or modifications of airway management.Trial registration ClinicalTrials.gov NCT03021551.

Apneic Oxygenation for Emergency Intubations in the Pediatric Emergency Department-A Quality Improvement Initiative

Introduction

Emergency airway management of critically ill children in the Emergency Department (ED) is associated with the risk of intubation-related desaturation, which can be minimized by apneic oxygenation. We evaluated the use of apneic oxygenation in the pediatric ED and reported a quality improvement initiative to incorporate apneic oxygenation as a routine standard of care during rapid sequence intubations (RSIs).

Methods

A baseline period from June 2016 to April 2017 highlighted the practice gaps. Quality improvement interventions were subsequently developed and implemented as a care bundle consisting of a pre-intubation checklist, placing reminders and additional oxygen source in resuscitation bays, incorporating into the responsibilities of the airway doctor and the airway nurse (copiloting), education during airway workshops and simulation training for doctors and nurses, as well as enhancing documentation of the intubation process. We monitored a post-intervention observation period from May 2017 to April 2018 for the effectiveness of the care bundle.

Results

Apneic oxygenation was not performed in all 22 RSIs during the baseline period. Among 25 RSIs in the post-intervention observation period, providers performed apneic oxygenation in 17 (68%) cases. There was no significant difference in the utilization of apneic oxygenation among emergency physicians and pediatric anesthetists performing RSIs in the pediatric ED.

Conclusions

We successfully implemented a care bundle targeted at incorporating apneic oxygenation as a routine standard of care during emergency intubations performed in ED. This method could be adopted by other pediatric EDs to improve airway management in critically ill children.

Acute Severe Asthma in Adolescent and Adult Patients: Current Perspectives on Assessment and Management

Asthma is a chronic airway inflammatory disease that is associated with variable expiratory flow, variable respiratory symptoms, and exacerbations which sometimes require hospitalization or may be fatal. It is not only patients with severe and poorly controlled asthma that are at risk for an acute severe exacerbation, but this has also been observed in patients with otherwise mild or moderate asthma. This review discusses current aspects on the pathogenesis and pathophysiology of acute severe asthma exacerbations and provides the current perspectives on the management of acute severe asthma attacks in the emergency department and the intensive care unit.

The HEAVEN criteria predict laryngoscopic view and intubation success for both direct and video laryngoscopy: a cohort analysis

Background

Existing difficult airway prediction tools are not practical for emergency intubation and do not incorporate physiological data. The HEAVEN criteria (Hypoxaemia, Extremes of size, Anatomic challenges, Vomit/blood/fluid, Exsanguination, Neck mobility) may be more relevant for emergency rapid sequence intubation (RSI).

Methods

A retrospective analysis included air medical RSI patients. A checklist was used to assess HEAVEN criteria prior to RSI, and Cormack-Lehane (CL) laryngoscopic view was recorded for the first intubation attempt. The incidence of a difficult (CL III/IV) laryngoscopic view as well as failure to intubate on first attempt with and without oxygen desaturation were determined for each of the HEAVEN criteria and total number of HEAVEN criteria. In addition, the association between HEAVEN criteria and both laryngoscopic view and intubation performance were quantified using multivariate logistic regression for direct laryngoscopy (DL) and video laryngoscopy (VL) configured with a Macintosh #4 non-hyperangulated blade.

Results

A total of 5137 RSI patients over 24 months were included. Overall intubation success was 97%. A CL III/IV laryngoscopic view was reported in 25% of DL attempts and 15% of VL attempts. Each of the HEAVEN criteria and total number of HEAVEN criteria were associated with both CL III/IV laryngoscopic view and failure to intubate on the first attempt with and without oxygen desaturation for both DL and VL. These associations persisted after adjustment for multiple co-variables including the other HEAVEN criteria.

Conclusion

The HEAVEN criteria may be useful to predict laryngoscopic view and intubation performance for DL and VL during emergency RSI.

Electronic supplementary material

The online version of this article (10.1186/s13049-019-0614-6) contains supplementary material, which is available to authorized users.

Characteristics of Desaturation and Respiratory Rate in Postoperative Patients Breathing Room Air Versus Supplemental Oxygen: Are They Different?

BACKGROUND

Routine monitoring of postoperative patients with pulse oximetry-based surveillance monitoring has been shown to reduce adverse events. However, there is some concern that pulse oximetry is limited in its ability to detect deterioration quickly enough to allow for intervention in patients receiving supplemental oxygen. To address such concerns, this study expands on the current limited knowledge of differences in desaturation and respiratory rate characteristics between patients breathing room air and those receiving supplemental oxygen.

METHODS

Pulse oximetry-derived data and patient characteristics were used to examine overnight desaturation patterns of 67 postoperative patients who were receiving either supplemental oxygen or breathing room air. The 2 modalities with respect to the speed of desaturation, in addition to magnitude and duration of desaturation events, are compared. Night-time pulse rate, oxygen saturation, respiratory rate, and the transition times from normal oxygen saturation levels to desaturated states are also compared. The behavior of respiratory rate in proximity to desaturation events is described. Statistical methods included multivariable regression and inverse probability of treatment weighted to adjust for any imbalance in patient characteristics between the oxygen and room air patients and linear mixed effect models to account for clustering by patient.

RESULTS

The study included 33 patients on room air and 34 receiving supplemental oxygen. The speed of desaturation was not different for room air versus oxygen for 2 types of desaturation (adjusted % difference, 95% confidence interval [CI]: type I; 22.4%, -51.5% to 209%; P = .67, type II; -17.3%, -53.8% to 47.6%; P = .52). Patients receiving supplemental oxygen had a higher mean oxygen saturation (adjusted difference, 95% CI, 2.4 [0.7-4.0]; P = .006). No differences were found for the average overnight respiratory or pulse rate, or proportion of time in desaturation states between the 2 groups.The time to transition from a normal oxygen saturation (92%) to 88% or below was not longer for supplemental oxygen patients (P = .42, adjusted difference 26.1%: 95% CI, -28.1% to 121%). Respiratory rates did not differ between the overall mean and desaturation or recovery phases or between the oxygen and room air group.

CONCLUSIONS

In this study, desaturation characteristics did not differ between patients receiving supplemental oxygen and breathing room air with regard to speed, depth, or duration of desaturation. Transition time for desaturations to reach low oxygen saturation alarms was not different, while respiratory rate remained in the normal range during these events. These findings suggest that pulse oximetry-based surveillance monitoring for deterioration detection can be used equally effectively for patients on supplemental oxygen and for those on room air.

Use of supplemental oxygen in emergency patients: a systematic review and recommendations for military clinical practice

INTRODUCTION

Supplemental oxygen is a key element of emergency treatment algorithms. However, in the operational environment, oxygen supply poses a challenge. The lack of high-quality evidence alongside emerging technologies provides the opportunity to challenge current guidelines. The aim of this review was to appraise the evidence for the administration of oxygen in emergency patients and give recommendations for its use in clinical practice.

METHODS

A critical review of the literature was undertaken to determine the evidence for emergency supplemental oxygen use.

RESULTS

Based on interpretation of the limited available evidence, five key recommendations are made: pulse oximetry should be continuous and initiated as early as possible; oxygen should be available to all trauma and medical patients in the forward operating environment; if peripheral oxygen saturations (SpO₂) are greater than or equal to 92%, supplemental oxygen is not routinely required; if SpO₂ is less than 92%, supplemental oxygen should be titrated to achieve an SpO₂ of greater than 92%; and if flow rates of greater than 5 L/min are required, then urgent evacuation and critical care support should be requested.

CONCLUSION

Oxygen is not universally required for all patients. Current guidelines aim to prevent hypoxia but with potentially conservative limits. Oxygen should be administered to maintain SpO₂ at 92% or above. New areas for research, highlighted in this review, may provide a future approach for oxygen use from point of injury to definitive care.

Airway management in pre-hospital critical care: a review of the evidence for a 'top five' research priority

The conduct and benefit of pre-hospital advanced airway management and pre-hospital emergency anaesthesia have been widely debated for many years. In 2011, prehospital advanced airway management was identified as a ‘top five’ in physician-provided pre-hospital critical care. This article summarises the evidence for and against this intervention since 2011 and attempts to address some of the more controversial areas of this topic.

Changing the Emergency Department's Practice of Rapid Sequence Intubation to Reduce the Incidence of Hypoxia

Rapid sequence intubation (RSI) is an advanced procedure performed by nurse practitioners in the emergency department (ED). Hypoxia is one of the most common complications associated with RSI, which may lead to serious sequela, including death. Hypoxia may result from medications that are given to facilitate the procedure or the underlying disease process. Without preventive measures, oxygen levels may fall rapidly when patients are no longer actively breathing. The incidence of RSI-induced hypoxia may be mitigated with proper education, preoxygenation, positioning, and the utilization of passive (apneic) oxygenation. The purpose of this project was to determine whether RSI practice could be changed through education and implementation of an evidence-based protocol in the ED of a hospital in south central United States. Baseline practice was determined by chart audits and compared with practice after educational sessions and protocol implementation. Change occurred as evidenced by an increase in the utilization of all 3 hypoxia prevention interventions included in the protocol. Staff education and utilization of a protocol changed the care provided, which can influence patient outcomes and decrease the incidence of RSI-induced hypoxia.

Development and Testing of a Novel Anaesthesia Induction/Ventilation Protocol for Patients With Cardiogenic Shock Complicating Acute Myocardial Infarction

BACKGROUND

Cardiogenic shock is a life-threatening condition and patients might require rapid sequence induction (RSI) and mechanical ventilation. In this study, we evaluated a new RSI/mechanical ventilation protocol in patients with acute myocardial infarction complicated by cardiogenic shock.

METHODS

We included consecutive adult patients who were transferred to the emergency department. The RSI protocol included 5 phases: preoxygenation, pretreatment, induction/paralysis, intubation, and mechanical ventilation (PPIIM). A posteriori, we selected historical patients managed with standard RSI as a control group. The primary outcome was hemodynamic derangement or hypoxemia from enrollment until intensive care unit (ICU) admission.

RESULTS

We studied 31 consecutive patients who were intubated using the PPIIM protocol and 22 historical controls. We found significant differences in systolic (85.32 ± 4.23 vs 71.72 ± 7.98 mm Hg; P < 0.0001), diastolic (58.84 ± 5.84 vs 39.05 ± 5.63 mm Hg; P < 0.0001), and mean arterial pressure (67.71 ± 4.90 vs 49.90 ± 5.66 mm Hg; P < 0.0001), as well as in partial pressure of oxygen (85.80 ± 19.82 vs 164.73 ± 43.07 mm Hg; P < 0.0001) between the PPIIM and control group at 5 minutes of automated ventilation. Also, statistically significant differences were observed in diastolic (59.74 ± 4.93 vs 47.86 ± 11.47 mm Hg; P < 0.0001) and mean arterial pressure (68.65 ± 4.10 vs 60.23 ± 11.67 mm Hg; P < 0.0001), as well as in partial pressure of oxygen (119.84 ± 50.57 vs 179.50 ± 42.17 mm Hg; P < 0.0001), and partial pressure of carbon dioxide (39.81 ± 10.60 vs 31.00 ± 9.30 mm Hg; P = 0.003) between the 2 groups at ICU admission. Compared with the control group, with PPIIM more patients survived to ICU admission (100% vs 77%) and hospital discharge (71% vs 31.8%), as well as at 90 days (51.6% vs 18.2%), and at 180 days (38.7% vs 13.6%).

CONCLUSIONS

The PPIIM protocol allows safe intubation of acute myocardial infarction patients with cardiogenic shock and improves hemodynamic and oxygenation parameters.

Implementation of a Clinical Bundle to Reduce Out-of-Hospital Peri-intubation Hypoxia

STUDY OBJECTIVE

Peri-intubation hypoxia is an important adverse event of out-of-hospital rapid sequence intubation. The aim of this project is to determine whether a clinical bundle encompassing positioning, apneic oxygenation, delayed sequence intubation, and goal-directed preoxygenation is associated with decreased peri-intubation hypoxia compared with standard out-of-hospital rapid sequence intubation.

METHODS

We conducted a retrospective, before-after study using data from a suburban emergency medical services (EMS) system in central Texas. The study population included all adults undergoing out-of-hospital intubation efforts, excluding those in cardiac arrest. The before-period intervention was standard rapid sequence intubation using apneic oxygenation at flush flow, ketamine, and a paralytic. The after-period intervention was a care bundle including patient positioning (elevated head, sniffing position), apneic oxygenation, delayed sequence intubation (administration of ketamine to facilitate patient relaxation and preoxygenation with a delayed administration of paralytics), and goal-directed preoxygenation. The primary outcome was the rate of peri-intubation hypoxia, defined as the percentage of patients with a saturation less than 90% during the intubation attempt.

RESULTS

The before group (October 2, 2013, to December 13, 2015) included 104 patients and the after group (August 8, 2015, to July 14, 2017) included 87 patients. The 2 groups were similar in regard to sex, age, weight, ethnicity, rate of trauma, initial oxygen saturation, rates of initial hypoxia, peri-intubation peak SpO₂, preintubation pulse rate and systolic blood pressure, peri-intubation cardiac arrest, and first-pass and overall success rates. Compared with the before group, the after group experienced less peri-intubation hypoxia (44.2% versus 3.5%; difference -40.7% [95% confidence interval -49.5% to -32.1%]) and higher peri-intubation nadir SpO₂ values (100% versus 93%; difference 5% [95% confidence interval 2% to 10%]).

CONCLUSION

In this single EMS system, a care bundle encompassing patient positioning, apneic oxygenation, delayed sequence intubation, and goal-directed preoxygenation was associated with lower rates of peri-intubation hypoxia than standard out-of-hospital rapid sequence intubation.

Systolic Blood Pressure Threshold for HEMS-Witnessed Arrests

OBJECTIVE

Defining vital sign thresholds has focused on mortality, which may be delayed for hours, days, or weeks after injury. This limits the immediate clinical significance in guiding therapy to avoid arrest. The aim of this study was to identify a systolic blood pressure (SBP) threshold indicating imminent cardiopulmonary arrest.

METHODS

This was a retrospective, observational study analyzing physiological data from air medical patients suffering witnessed arrest. We limited the analysis to a subgroup of adult (> 14 years) patients with hypoperfusion-related arrest. Prearrest SBP values were plotted over time, with arrest defined as "time zero." Multiple linear regression was used to define a best fit curve to identify an inflection point beyond which arrest was imminent.

RESULTS

A total of 53 eligible patients were identified; 33 (62%) were trauma victims. A fifth-degree equation showed appropriate goodness of fit (r = -.66, P < .0001). An inflection point was identified at an SBP of 78 mm Hg, with arrest occurring approximately 3 minutes later.

CONCLUSION

An inflection point below SBP 80 mm Hg was identified, suggesting a predictable physiological pattern for perfusion-related deterioration. This may help guide therapy to reverse deterioration and prevent arrest.

Delayed Sequence Intubation by Intensive Care Flight Paramedics in Victoria, Australia

OBJECTIVE

Delayed sequence intubation (DSI) involves the administration of ketamine to facilitate adequate preoxygenation in the agitated patient. DSI was introduced into the Clinical Practice Guideline for Intensive Care Flight Paramedics in Victoria in late 2013. We aimed to describe the clinical characteristics of patients receiving DSI.

METHODS

A retrospective analysis was undertaken of patients who received DSI between January 1, 2014, and December 31, 2016, during both primary response and retrieval missions. Patients' clinical characteristics, DSI success rates, and complications were determined from electronic patient care records.

RESULTS

Forty patients received DSI during the study period. Of these, 32 were intubated to manage traumatic injury and the remaining 8 were intubated for medical reasons. On arrival of the first road ambulance, median oxygen saturation was 96.5%, and immediately prior to DSI the median was 98.0%. One patient had a period of self-limiting apnea (< 15 seconds) following ketamine administration. Oxygen saturation was either maintained or increased prior to laryngoscopy in all patients. Post-intubation, one patient experienced bradycardia (heart rate < 60 beats per minute), two patients had a systolic blood pressure drop of > 20 mm Hg, one patient experienced an increase in heart rate of > 20 beats per minute, and two patients had transient oxygen desaturation (< 85%). No patients experienced cardiac arrest or required surgical airway intervention. All patients were successfully intubated. After DSI, the median oxygen saturation was 100%.

CONCLUSIONS

DSI provides a reasonably safe and effective approach for intensive care flight paramedics in the preoxygenation of agitated, hypoxic patients in order to decrease the risk of peri-intubation desaturation and related hypoxic injury.

Student paramedic rapid sequence intubation in Johannesburg, South Africa: A case series

Introduction

Pre-hospital rapid sequence intubation was introduced within paramedic scope of practice in South Africa seven years ago. Since then, little data has been published on this high-risk intervention as practiced operationally or by students learning rapid sequence intubation in the pre-hospital environment. The objective of this study was to describe a series of pre-hospital rapid sequence intubation cases, including those that South African University paramedic students had participated in.

Methods

A University clinical learning database was searched for all endotracheal intubation cases involving the use of neuromuscular blockers between 1 January 2011 and 31 December 2015. Data from selected cases were extracted and analysed descriptively.

Results

Data indicated that most patients were young adult trauma victims with a dominant injury mechanism of vehicle-related accidents. The majority of cases utilised ketamine and suxamethonium, with a low rate of additional paralytic medication administration. 63% and 72% of patients received post-intubation sedation and analgesia, respectively. The overall intubation success rate from complete records was 99.6%, with a first pass success rate of 87.9%. Students were successful in 92.4% of attempts with a first-pass success rate of 85.2%. Five percent of patients experienced cardiac arrest between rapid sequence intubation and hospital arrival.

Discussion

Students demonstrated a good intubation success and first pass-success rate. However, newly qualified paramedics require strict protocols, clinical governance, and support to gain experience and perform pre-hospital rapid sequence intubation at an acceptable level in operational practice. More research is needed to understand the low rate of post-intubation paralysis, along with non-uniform administration of post-intubation sedation and analgesia, and the 5% prevalence of cardiac arrest.

Implementation of NAP4 emergency airway management recommendations in a quaternary-level pediatric hospital

Emergency airway management, particularly outside of the operating room, is associated with a high incidence of life-threatening adverse events. Based on the recommendations of the 4th National Audit Project, we aimed to develop hospital-wide systems changes to improve the safety of emergency airway management. We describe a framework for governance in the form of a hospital airway special interest group. We describe the development and implementation of the following systems changes: 1. A local intubation algorithm modified from the Difficult Airway Society's plan A-B-C-D approach, including clear pathways for airway escalation, and emphasizing the concepts of resuscitation prior to intubation, planning for failure, and avoidance of fixation error. 2. Simplified and standardized airway equipment located in identical airway carts in all critical care areas. 3. A preintubation checklist and equipment template to standardize preparation for airway management. 4. Availability of continuous waveform endtidal capnography in all critical care areas for confirmation of correct endotracheal tube placement. 5. Multidisciplinary team training to address the technical and nontechnical aspects of nonoperating room intubation. In addition, we describe methodology for ongoing monitoring of performance through a quality assurance framework. In conclusion, changes in the process of emergency airway management at a hospital level are feasible through collaboration. Their impact on patient-based outcomes requires further study.

Apneic oxygenation is associated with a reduction in the incidence of hypoxemia during the RSI of patients with intracranial hemorrhage in the emergency department

Critically ill patients undergoing emergent intubation are at risk of oxygen desaturation during the management of their airway. Patients with intracranial hemorrhage (ICH) are particularly susceptible to the detrimental effects of hypoxemia. Apneic oxygenation (AP OX) may be able to reduce the occurrence of oxygen desaturation during the emergent intubation of these patients. We sought to assess the effect AP OX on oxygen desaturation during the rapid sequence intubation (RSI) of patients with ICH in the emergency department (ED). We prospectively collected data on all patients intubated in an urban academic ED over the 2-year period from July 1, 2013 to June 30, 2015. Following each intubation, the operator completed a standardized continuous quality improvement (CQI) data form, which included information on patient, operator and intubation characteristics. Operators recorded data on the use of AP OX, the oxygen flow rate used for AP OX, and the starting and lowest saturations during intubation. Adult patients with ICH who underwent RSI by emergency medicine (EM) residents were included in the analyses. The primary outcome variable was any oxygen saturation <90 % during the intubation. We performed a backward stepwise multivariate logistic regression analysis to identify variables associated with oxygen desaturation. The primary independent variable of interest was the use of AP OX during the intubation. Inclusion criteria for the study was met by 127 patients. AP OX was used in 72 patients (AP OX group) and was not used in 55 patients (NO AP OX group). The incidence of desaturation was 5/72 (7 %) in the AP OX group and was 16/55 (29 %) in the NO AP OX group. In the multivariate logistic regression analysis the use of AP OX was associated with a reduced odds of desaturation (aOR 0.13; 95 % CI 0.03-0.53). Patients with ICH who received AP OX during RSI in the ED were seven times less likely to have an oxygen saturation of <90 % during the intubation compared to patients who did not receive AP OX. AP OX is a simple intervention that may minimize the risk of oxygen desaturation during the RSI of patients with ICH.

Apneic Oxygenation May Not Prevent Severe Hypoxemia During Rapid Sequence Intubation: A Retrospective Helicopter Emergency Medical Service Study

OBJECTIVE

This study sought to determine the effectiveness of apneic oxygenation in preventing hypoxemia during prehospital rapid sequence intubation (RSI).

METHODS

We performed a case-cohort study using a pre-existing database looking at intubation management by a single helicopter emergency medical service between July 2013 and June 2015. Apneic oxygenation using high-flow nasal cannula (15 L/min) was introduced to the standard RSI protocol in July 2014. Severe hypoxemia was defined as an incidence of oxygen saturation less than 90%. We compared patients who received apneic oxygenation during RSI with patients who did not using the Fisher exact test.

RESULTS

Ninety-three patients were identified from the database; 29 (31.2%) received apneic oxygenation. Nineteen patients had an incidence of severe hypoxemia during RSI (20.43%; 95% confidence interval, 12.77%-30.05%). There was no statistically significant difference between the rate of severe hypoxemia between patients in the apneic oxygenation group versus the control group (17.2% vs. 21.9%, P = .78).

CONCLUSION

In this study, patients who received apneic oxygenation did not show a statistically significant difference in severe hypoxemia during RSI.

First Pass Success Without Hypoxemia Is Increased With the Use of Apneic Oxygenation During Rapid Sequence Intubation in the Emergency Department

OBJECTIVES

The objective was to determine the effect of apneic oxygenation (AP OX) on first pass success without hypoxemia (FPS-H) in adult patients undergoing rapid sequence intubation (RSI) in the emergency department (ED).

METHODS

Continuous quality improvement data were prospectively collected on all patients intubated in an academic ED from July 1, 2013, to June 30, 2015. During this period the use of AP OX was introduced and encouraged for all patients undergoing RSI in the ED. Following each intubation, the operator completed a standardized data form that included information on patient, operator, and intubation characteristics. Adult patients 18 years of age or greater who underwent RSI in the ED by emergency medicine residents were included in the analysis. The primary outcome was FPS-H, which was defined as successful tracheal intubation on a single laryngoscope insertion without oxygen saturation falling below 90%. A multivariate logistic regression analysis was performed to determine the effect of AP OX on FPS-H.

RESULTS

During the 2-year study period, 635 patients met inclusion criteria. Of these, 380 (59.8%) had AP OX utilized and 255 (40.2%) had no AP OX utilized. In the AP OX cohort the FPS-H was 312/380 (82.1%) and in the no AP OX cohort the FPS-H was 176/255 (69.0%) (difference = 13.1%, 95% confidence interval [CI] = 6.2% to 19.9%). In the multivariate logistic regression analysis, the use of AP OX was associated with an increased odds of FPS-H (adjusted odds ratio = 2.2, 95% CI = 1.5 to 3.3).

CONCLUSIONS

The use of AP OX during the RSI of adult patients in the ED was associated with a significant increase in FPS-H. These results suggest that the use of AP OX has the potential to increase the safety of RSI in the ED by reducing the number of intubation attempts and the incidence of hypoxemia.

Advanced airway management for pre-hospital trauma patients

The need for timely and appropriate airway management for trauma patients is widely recognised. There are a small number of severely injured patients who cannot be adequately supported with basic airway manoeuvres, and require early advanced airway management. The way in which this care is provided remains highly controversial. Whilst it is clear that effective airway management remains a priority for all patients and poorly performed pre-hospital anaesthesia may be detrimental to patient outcome, debate remains over exactly which patients will benefit from early advanced airway interventions, and how it should be provided. The evidence base is small and inconsistent, with significant heterogeneity in the reported data, making it impossible to draw meaningful conclusions. Current practice is not standardised, and care is delivered by providers of different abilities using a range of equipment and techniques. Standards of care provided during in-hospital practice relating to these issues of provider competence, equipment, and monitoring should be directly translated into delivery of care outside the hospital, but this is not always the case. The aim of this review is to evaluate the current evidence surrounding pre-hospital advanced airway management.

Apneic Oxygenation during Rapid Sequence Intubation in Critically Ill Children

This prospective case series documented hypoxemia and potential complications associated with apneic oxygenation in critically ill pediatric patients during rapid sequence intubation. Forty-four patients received apneic oxygenation via nasal cannula at rates of 5, 10, and 15 L/min for ages <4, 4 to 12, and 12 to 18 years, respectively. Pre- and postintubation attempt mean Spo ₂ were 98.9 ± 2.95 and 90.7 ± 1.95%, respectively. Postintubation Spo ₂ < 80% were significantly less with one intubation attempt, compared with multiple attempts (p < 0.001). No serious complications were noted. Apneic oxygenation was well tolerated in critically ill children.

Incidence and Duration of Continuously Measured Oxygen Desaturation During Emergency Department Intubation

STUDY OBJECTIVE

Desaturation during intubation has been associated with serious complications, including dysrhythmias, hemodynamic decompensation, hypoxic brain injury, and cardiac arrest. We seek to determine the incidence and duration of oxygen desaturation during emergency department (ED) rapid sequence intubation.

METHODS

This study included adult rapid sequence intubation cases conducted between September 2011 and July 2012 in an urban, academic, Level I trauma center ED. We obtained continuous vital signs with BedMasterEX data acquisition software. Start and completion times of rapid sequence intubation originated from nursing records. We defined oxygen desaturation as (1) cases exhibiting SpO2 reduction to less than 90% if the starting SpO2 was greater than or equal to 90%, or (2) a further reduction in SpO2 in cases in which starting SpO2 was less than 90%. We used multivariable logistic regression to predict oxygen desaturation during rapid sequence intubation.

RESULTS

During the study period, there were 265 rapid sequence intubation cases. The study excluded 99 cases for failure of electronic data acquisition, inadequate documentation, or poor SpO2 waveform during rapid sequence intubation, and excluded cases managed by anesthesia providers, leaving 166 patients in the analysis. After preoxygenation, starting SpO2 was greater than 93% in 124 of 166 cases (75%) and SpO2 was less than 93% in the remaining 46 cases. Oxygen desaturation occurred in 59 patients (35.5%). The median duration of desaturation was 80 seconds (interquartile range 40, 155). Multivariable analysis demonstrated that oxygen desaturation was associated with preintubation SpO2 less than 93% (odds ratio [OR] 5.1; 95% confidence interval (CI) 2.3 to 11.0), multiple intubation attempts (>1 attempt) (OR 3.4; 95% CI 1.4 to 6.1), and rapid sequence intubation duration greater than 3 minutes (OR 2.7; 95% CI 1.2 to 6.1).

CONCLUSION

In this series, 1 in 3 patients undergoing ED rapid sequence intubation experienced oxygen desaturation for a median duration of 80 seconds. Preintubation saturation less than 93%, multiple intubation attempts, and prolonged intubation time are independently associated with oxygen desaturation. Clinicians should use strategies to prevent oxygen desaturation during ED rapid sequence intubation.

Preoxygenation reduces desaturation events and improves intubation success

OBJECTIVE

Oxygen desaturation occurs frequently in the course of prehospital rapid sequence intubation (RSI) and is associated with increased morbidity and mortality. Preoxygenation with positive pressure ventilation by bag valve mask may delay the onset of desaturation. The purpose of this study was to evaluate implementation of a targeted preoxygenation protocol including the use of positive pressure ventilation on desaturation events and intubation success during air medical RSI.

METHODS

The RSI air medical program airway training model was modified to target an oxygen saturation as measured by pulse oximetry value of ≥ 93% before initial laryngoscopy. A review of oxygen saturation as measured by pulse oximetry tracings was performed for 2 years before and 2 years after implementation of this protocol. The incidence of desaturation events and overall intubation success rates were compared before and after the intervention.

RESULTS

One hundred fifty-five RSI procedures were evaluated over the study period. Desaturation events decreased from 58% in the 2 years before algorithm changes to 28% in the first year and 14% in the second year after implementation (P < .01). Intubation success rates increased from 89% to 98% (P < .01). There were no self-reports of aspiration events during the study period.

CONCLUSION

A preoxygenation protocol dramatically reduced the incidence of desaturation events and increased intubation success without an increase in the number of reported aspiration events.

The incidence of oxygen desaturation during rapid sequence induction and intubation

BACKGROUND

Rapid sequence induction and intubation (RSII) is an emergency airway management technique for patients with a risk of pulmonary aspiration. It involves preoxygenation, administration of predetermined doses of induction and paralytic drugs, avoidance of mask ventilation, and laryngoscopy followed by tracheal intubation and keeping cricoid pressure applied till endotracheal tube cuff be inflated. Oxygen desaturation has been seen during RSII. We assessed the incidence of oxygen desaturation during RSII.

METHODS

An institution-based observational study was conducted from March 3 to May 4, 2014 in our hospital. All patients who were operated upon under general anesthesia with RSII during the study period were included. A checklist was prepared for data collection.

RESULTS

A total of 153 patients were included in this study with a response rate of 91.6%. Appropriate drugs for RSII, equipments for RSII, equipments for difficult intubation, suction machine with a catheter, a monitor and an oxygen backup such as ambu bag were not prepared for 41 (26.8%), 50 (32.7%), 51 (33.3%), 38 (24.8%) and 25 (16.3%) patients respectively. Cricoid pressure was not applied at all for 17 (11.1%) patients and 53 (34.6%) patients were ventilated after induction of anesthesia but before intubation and endotracheal cuff inflation. A total of 55 (35.9%) patients desaturated during RSII (SPO2<95%). The minimum, maximum and mean oxygen desaturations were 26%, 94% and 70.9% respectively. The oxygen desaturation was in the range of <50%, 50%-64%, 65%-74%, 75%-84%, 85%-89 % and 90%-94% for 6 (3.9%), 7 (4.6%), 5 (3.3%), 10 (6.5%), 13 (8.5%) and 14 (9.2%) patients respectively.

CONCLUSION

The incidence of oxygen desaturation during RSII was high in our hospital. Preoperative patient optimization and training about the techniques of RSII should be emphasized.