JOURNAL PRESENTATION Al Jadidi Bin Sulaiman Moderator : Dr Abdul Karim
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 suxbcoz 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 RSII Onset time of rocuronium 1mg/kg is around 60s Its 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.
Methodology Patients were randomised 1:1 according to computer-generated list Patients 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 awareness Assessment of generalised muscle ache
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
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 ptsie 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 unremarkable Airway 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 fade An 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 anaesthetics1 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 reassessed Repeated 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.