Rapid sequence induction (RSI) Dr. S. Parthasarathy MD., DA., DNB, Dip. Diab. DCA, Dip. Software based statistics- PhD ( physiology), IDRA
Rapid sequence induction (RSI) is a method of achieving rapid control of the airway whilst minimising the risk of regurgitation and aspiration of gastric contents. What is the concept ?
Time between loss of protective airway reflexes to insertion of cuffed endotracheal tube to be kept minimum The scenario ?? Especially Unprepared patient with a risk of aspiration
What is the difference Sedate Mask ventilation sufficient – check Make them apneic Intubate Take that risk
What is the risk of aspiration ?? 1 in 2000 to 1 in 14000 It varies But the mortality – 1 in 72000 Obtunded patients – no RSI ?? Intubate
History Stept and Safar in 1970 Conscious or unconscious patient with full stomach Intracranial pathology and trauma 15 step process for two years
Seven P s of RSI Evolved now as Preparation Pre oxygenation Pretreatment Paralyses Positioning Prove placement Post intubation management
Preparation Equipment Drugs and support staff SOAPME Suction oxygen airway evaluation pharmacology, monitors , equipment for difficult airway
Preoxygenation 100 % oxygen for 3-5 minutes 4 vital capacity breaths Pregnancy , obesity, cardio respiratory disease Elderly and children desaturate earlier
Pretreatment Atropine - ? Use. Only the second dose of succinyl choline Opioids – the original drugs were long acting – but after fentanyl and analogues – OK One tenth the dose of NDPs – but the dose of scoline – 2 mg/kg minimal – penetrating eye injury – distressing few seconds because 3 minutes is the ideal pre time – for not that emergent cases Lignocaine 1 – 2 mg/kg – used prior to the advent of newer opioids
Paralyses with induction Safar started with predetermined dose of thio and scoline 150 and 100 respectively for a 70 kg patient Intravenous induction facilitates loss of consciousness in one arm–brain circulation time, minimizing the time from loss of consciousness to intubation. Ideally, the chosen induction agent should provide a rapid onset and a rapid recovery from anaesthesia with minimal cardiovascular and systemic side effects.
Paralyses - continued Thiopentone 3- 5 mg / kg – fast Propofol 1 mg/ kg but depression of reflexes better Midaz and ketamine for shocked patients and Etomidate for hemodynamic stability Acidic relaxants and alkaline thio – precipitate – loss of IV lines
1 is ok in non precurarized patients Dose of scoline 0.6 1 1.5 to 2 1 is ok in non precurarized patients
Non depolarizers Rocuronium comes nearer Crush injury , raised ICP or IOP , hyperkalemia 0.6 mg / kg – ok intubating conditions in 1 minute But 0.9 – 1.2 means – excellent – long acting but want to reverse in CICV, suggamadex
Priming and timing One tenth of the nondepolarizer is given prior three minutes to original dose Partial weakness problem Timing – means give the full dose just prior to thiopentone
Positioning Sniffing position
Sellick maneuver Separate slides in website From the internet for closed academic purpose only
Prove Confirm and prove placement of endotracheal tube in the correct position Visual Stethoscope Capnograph
Post intubation managemant Need for mechanical ventilation Monitoring Vital signs
Modified rapid sequence induction Trial of mask ventilation Use of nondepolarizers Proseal LMA Rapid sequence induction (RSI) or Rapid sequence airway
Name Rapid sequence induction (RSI) ? Actually Rapid sequence intubation ? !
Clinical implications Emergency surgical procedures Special – peritonitis Abdominal distension Opioids Trauma alcohol Pain Ryles tube insertion may not eliminate the risks
Pregnancy Physical and physiological changes – prone Elective LSCS is RSI ( 95 % anesthesiologists prefer) Thio and scoline obvious choice Rocuronium, difficult cricoid pressure , possible proseal ??
Morbid obesity and RSI Weight and drug dosage CVS and RS changes Fatty neck Comorbidities Prone for aspiration And go ahead with RSI
Neonates Inhalational agents or without it also Prone for arrhythmias , desaturation, intra ventricular hemorhage, vocal cord injuries and a longer time ?? RSI is acceptable when there are no facial or airway anomalies
So many !! inadvertent esophageal intubation, esophageal perforation, and trauma to the lips, gums, or tongue. Vocal folds edema, ulcerations of the arytenoids, ulcerations of the posterior glottis, and ulcerations of the main stem bronchus have been described in the literature
Thiopentone 3 -7 mg / kg but slow Succinyl choline 1.5 mg/ kg Atropine 0.1 mg Fentanyl – 1- 2 mic/kg Thiopentone 3 -7 mg / kg but slow Succinyl choline 1.5 mg/ kg IM RSI also described Lot of modifications No propofol
Outside the operation theatre – ER Can be done by non anesthesiologists also Can be done by technicians also Urgent – no 100 % oxygen also Only with sedatives Sedative facilitated intubation (SFI) – midaz and ketamine with atropine is used for that purpose
ICU Hypoxic acidotic and collapsed stage RSI decreased the morbidity by 50% Two operators Experienced staff
Preoxygenation – must 500 ml crystalloids – vasopressors Minimum diastolic – 35 mmHg preferable Newer short acting opioids Etomidate Scoline
Prehospital RSI Arrest Trauma Hypoxic Unstable patients Gagging , uncooperative patients made failure common Hence RSI
Extubation also important In patients for whom an RSI was indicated due to aspiration risk, emergence remains a high-risk time for further aspiration events. Awake patient with intact reflexes Left lateral head-down positioning may further reduce the chance of aspiration, at the expense of reduced access to the airway.
Complications of RSI Drugs Cricoid pressure Due to intubation or due to “cant do it”
CICV Release CP Insert LMA Keep CP again Try to ventilate Still no – means – take out CP and try
Difficult airway 2 % Hypoxia – 2% Hypotension – 0.7 % Hypertension - ? Arrhythmias -? Scoline and arrhythmias !!
Rupture of esophagus Clear cut vomiting during RSI, relax CP and suck 20 or 30 40 N pressure Possible but rare cricoid fractures Awareness – worst may be upto 50 % Think of high doses of Thio – 7 mg/kg in fit individuals
Summary What is it ? And the concept – name ? Preparation ,Pre oxygenation ,Pretreatment Paralyses, Positioning ,Prove placement Post intubation management Outside the OR Neonates Complications