AL JADIDI BIN SULAIMANMODERATOR : DR ABDUL

KARIM

JOURNAL PRESENTATION

Introduction

Rapid sequence induction and intubation (RSII) is performed when there is an increased risk of pulmonary aspiration of gastric contents

Consists of following:-optimal positioning of the patient, pre-oxygenation, injection of opioid & hypnotic agent, injection of fast acting NMBA, cricoid pressure & tracheal intubation

Succinylcholine has been for a long time the NMBA of choice for RSII, because of quick onset, with excellent intubating conditions.

However it is desirable to identify an alternative to sux bcoz of its s/e & risk of delayed recovery of neuromuscular function

Spontaneous recovery of a succinylcholine-induced neuromuscular block may take too long to avoid desaturation in a ‘cannot intubate, cannot ventilate’ (CICV) situation

In some patients, the hydrolysis of succinylcholine may be severely impaired as a result of genetic or acquired low cholinesterase activity

Rocuronium..

Can be used for RSIIOnset time of rocuronium 1mg/kg is around

60sIts duration of action however, 122 (33) min

(from injection to recovery of 1st twitch of TOF to 75% of baseline) for single bolus of 0.9mg/kg

Sugammadex; binds the rocuronium molecules in a 1:1 ratio without having an effect on the plasma cholinesterase or on any receptor systems in the human body

Even profound neuromuscular block with rocuronium can be quickly antagonised with sugammadex

Aim of this trial..To assess the time from verified correct

tracheal tube placement after RSII until regular and spontaneous ventilation was re-established

Assess the intubating conditions and the duration of action of NMBA; using acceleromyography

Hypothesized that the time from correct tracheal tube placement to spontaneous ventilation would be shorter with rocuronium followed by sugammadex, than with succinylcholine

Pts were eligible if they were between 18 to 60 y/o and undergoing RSII

Exclusion criteria:- Known allergic to propofol, alfentanil, succinylcholine, rocuronium, sugammadex, pt undergoing emmergency surgery (op scheduled <24H), BMI>35 kg/m2, severe renal disease, NYHA >2, K+ >5.0 mmol/L, untreated glaucoma, neuromuscular disease, a known disposition for MH, female pts of child-bearing potential, & breastfeeding women.

MethodologyPatients were randomised 1:1 according to

computer-generated listPatients either receive either

succinylcholine (1mg/kg) or rocuronium (1mg/kg) followed by sugammadex (16mg/kg)

The patients were monitored with a 3 lead ECG, NIBP, and pulse oximetry. Hypnotic depth was assessed using BIS.

Neuromuscular monitoring was performed using TOF connected to a computer

After induction of anesthesia, supramaximal stimulation was ensured, every 15s, a TOF pattern was delivered

This is done in order to get stable plateu

Primary outcome

Time from correct placement of the tracheal tube (confirmed by auscultation after intubation) until re-establishmentof spontaneous ventilation

RR 8bpm, Vt >3ml/kg, SpO2 >90% for 30s.Vt was measured using built-in spirometer in

the anesthetic machine

Secondary outcome

Duration of action of NMBA measured with TOF from start of injection of NMBA to recovery of T1 in TOF to above 90% (T190%),

& from tracheal intubation to recovery of T1 to 90%

Other parameters..

Intubation difficulty scale (IDS) and intubation condition were also assessed.

Adverse event reported by a non blinded investigator

Possibility of awarenessAssessment of generalised muscle ache

RESULTS

In the succinylcholine group,-desaturation to 80% (n=1), bronchospasm (n=1), severe generalised muscle ache (n=2),and unanticipated difficult intubation, defined by IDS value above 5

Adverse events of importance during induction in the rocuronium-sugammadex group were: urticaria in surgical zone after chlorhexidine application (n=1) & tachycardia to above 100bpm (n=3)

Recall was not suspected in any of the patients within 24H after operation

Discussion

Spontaneous ventilation was re-established significantly earlier using rocuronium-sugammadex for RSI

The difference in median values was around 3 minutes, even greater diference was found in the recovery

Only elective patients included. This was done for practical and research ethical reason

It would be difficult to strictly standardize the anesthetic procedure in emergency pts ie unstable haemodynamic and fluid deficit

Findings are not applicable to obese, because the intubating dose of rocuronium should not be 1mg/kg according to total body weight

In the rocuronium group, intubation condition tend to be better and a lower IDS was observed

This tendency is in contradiction with the conclusion of systematic Cochrane review reporting succinylcholine to be superior to rocuronium (all doses) in creating optimal intubation conditions.

Possible reasons:- 1mg/kg rocuronium used, intubation was done

as late as 60sec.- All pts receive 2mg/kg propofol, likely improved

intubation conditions when compared with a smaller dose or a different hypnotic.

The most serious adverse effects of succinylcholine are bradycardia, asystole, elevation of plasma K+, and MH.

Sugammadex has a low incidence of adverse effects and the profile of adverse events has so far not been serious

The genotype of the butyrylcholinesterase is known to be importance for the ability to metabolise succinylcholine, explain the variability in time to recover from succinylcholine –induced block.

DIBUCAINE NUMBER..

Studies have shown that succinylcholine is a/w more rapid desaturation than rocuronium during RSII

Pt with BMI 25-30 kg/m2 had a 46s difference in time to desaturation to 92% between succinylcholine and rocuronium

RSII using rocuronium seems to be a/w later onset of desaturation and better intubation conditions due to the prolonged duration of action.

The safety of RSII can be enhanced when using rocuronium if sugammadex is available as an escape drug

Recommend a strict RSII protocol, where the sugammadex dose is calculated, drug readily available in OT although not drawn up, syringes are prepared for emergency draw up before initiation of RSII.

#Manikin study stated that in CICV scenario, the time to calculate the correct dose of drug and draw up is 6.7min..

In conclusion, RSII with rocuronium followed by sugammadex allowed earlier re-establishment of spontaneous ventilation than with succinylcholine

A 78-year old woman with 4 months h/o dysphonia & dysphagia presented for an elective panendoscopy and left-sided tonsillectomy

Her medical hx was unremarkableAirway assessment: mallapati 3, 4cm mouth

opening, tyromental distance 7cm, full dentition.

Nasoendoscopy 2 weeks previously revealed a swelling in the left tonsil with oedematous uvula which partially obscured the view of pharynx, VC and larynx appear normal

CT scan performed the day before surgery reported a large enhancing mass lesion in the region of the left palatine tonsil with significant bilateral cervical lymph node and narrowed airway at the level of hyoid.

Intubation was anticipated to be difficult, mask ventilation was anticipated to be possible

Intubation plan;- Induction of GA with direct laryngoscopy, - Secondary plan; use alternative blade /

glidescope- Tertiary plan; wake the pt up, reverse with

sugammadex

Pt was preO2 for 4 min, then iv fentanyl 75mcg, propofol 160mg given

This was followed immediately with rocuronium bromide 40mg (0.61mg/kg)

Bag mask-ventilation was easily achieved and lungs were ventilated with fio2 of 1.0 and sevoflurane at end-tidal concentration of 1.9%.

After 2 min, gentle DL was performed with a Mac size 3.

On laryngoscopy, the anatomy was unidentifiable because of a large, rigid, fungating mass in the oropharynx and obliterating any view of the larynx or epiglottis

Direct laryngoscopy was abandoned and bag-mask ventilation successfully recommenced

Glidescope was attempted but contact bleeding had commenced

2nd consultant anesthetist performed DL with a size 4 Mac blade but was also unsuccessful

Bag-mask ventilation had now become increasingly difficult, despite the use of Guedel airway and 2 person mask ventilation

Size 3 LMA also inserted but ventilation was not possible, thus it was removed

CICV scenario was now recognised & the decision made to awaken the patient

SpO2 level remained 98%The volatile agent was turned off, and

sugammadex 1g (15.4 mg/kg) within 30sec of the decision to awaken the patient being made

This was ~6min after the administration of rocuronium

A nerve stimulator was attached to the patient

After 60sec, spontaneous chest wall movement was observed

TOF stimulation showed no evidence of fadeAn obstructed pattern of breathing was

witnessed with no capnography trace or movement of reservoir bag

Spo2 had now decreased to 92%, so an adult Ravussin cannula was inserted through the cricothyroid membrane to achieve rescue oxygenation

This was followed by oxygenation with the Manujet, initial pressure 0.5bar, rate 5bpm

The driving pressure was increased to 1bar to achieve adequate Vt & SpO2 increased to 98%

What can we discuss..

CICV situations are an anaesthetic emergency requiring rapid and decisive management

Rare, incidence during all anaesthetics 1 in 50000.

Incidence is higher in pts with head and neck pathology

Both the ASA & Difficult Airway Society (DAS) have published guidelines on the mx of CICV situations

Introduction of sugammadex, with its rapid reversal of even profound neuromuscular block, lead to the suggestion that it is a potential rescue strategy in CICV situations.

4th National audit project (NAP4) of the Royal College of Anesthetists and DAS report found that in head & neck pathology, repeated attempts at laryngoscopy were a common cause of airway deterioration and morbidity

The use of sugammadex in this case reverse rocuronium neuromuscular block, shown by the presence of TOF with no fade, although this may not be a/w a restoration of a patent upper airway

Sugammadex may have a role in the mx of CICV situations of different aetiology; however rescue oxygenation techniques should be used in timely fashioned if required.

If sugammadex is a part of rescue mx plan, then it should be used early in the mx of difficult airway situation, before repeated airway manipulations

Airway mx plan needs to be reassessedRepeated nasoendoscopy may be appropriate

to Ix the discrepancy between the previous nasoendoscopy and the CT scan

Likely lead to consideration of awake fibreoptic intubation (may have failed otherwise) or a prophylactic cricithyroid cannula

Finally, it is important that all members of the operative team are briefed in advance of any

potential difficulties and are aware of a stepwise plan in order to allow adequate preparation and effective management of

such emergencies.

Thank you for listening…