Original Article Two Forgotten Induction Agents; Etomidate versus Thiopental Sodium with Rocuronium for Rapid Sequence Induction Syeda Asma Khalid, Syed Hamid Ali, Sadqa Aftab, Waqar H. Kazmi Abstract Objective: To assess the effect on intubating conditions and haemodynamic response on intubation of two different induction agents etomidate and thiopental sodium with rocuronium during rapid se- quence induction. Methods: This prospective quasi experimentalstudy was conducted in Department Of Anaesthesia, SICU and Pain Management, Dow Medical College, Civil Hospital Karachi and Abbasi Shaheed Hos- pital Karachi Medical and Dental College over a period of one year. Total 120 American Society of Anaesthesiologists (ASA) physical class I and II, adult patients of either gender, aged between 18 to 60 years, undergoing elective surgery were allocated randomly into two equal groups to receive either intravenous thiopental sodium (Group NTR) or etomidate(Group NER) for rapid sequence induction. Group NER was given nalbuphine 0.1mg/kg, induction agent etomidate 3 mg/kg with muscle relaxant rocuronium 1.0 mg/kg while in group NTR induction agent thiopental sodium was given in the dose of 4 mg/kg with nalbuphine and rocuronium in the same doses. After sixty seconds, laryngoscopy was done. Intubating condition was assessed using the criteria of Cooper and colleagues: ease of intubation, condition of vocal cords and response to intubation. Cardiovascular response on intuba- tion in terms of systolic and diastolic blood pressure and heart rate was evaluated at 0,1, 3 and 5 minutes. Results: Demographic data were comparable between the groups. Intubating conditions which were assessed in terms of ease of laryngoscopy, condition of vocal cords at intubation and intubation re- sponse coughing, bucking and diaphragmatic movement were significantly better in the group NER (p<0.05). Similarly, arterial blood pressure remained close to base line in NER group but there was significant fall in both systolic and diastolic blood pressure in group NTR. However, there was no sig- nificant difference in change in the heart rate in the groups. Conclusion: Etomidate-rocuronium is better than thiopental-rocuronium in terms of intubating condi- tions and haemodynamic stability during rapid sequence induction in non-septic surgical patients in emergency department. Keywords: Etomidate, thiopental sodium, nalbuphine intubation, rocuronium, laryngoscopy. (ASH & KMDC 19(2):79;2014). Introduction properties. Nothing had yet replaced succinylcholine in the scenarios of difficult intubation before but with Rapid sequence induction (RSI) is the advent of rocuronium antagonist (ORG-25969, standard anaesthetic technique and the depol- sugamedax) that chelates the drug and act as the arizing neuromuscular agent succinylcholine has reversal agent, rocuronium can also be used in been the drug of choice for RSI and anticipated difficult intubation situations in RSI. However, difficult intubations for its short and rapid acting ______________________________________________________________________________________________ rocuronium is the suitable alternative, equally rapid Department of Anaesthesia, acting muscle relaxant in the recommended doses Abbasi Shaheed Hospital, KMDC, Karachi for RSI (2or3xED95) where succinylcholine is Correspondance: Dr. Syeda Asma Khalid relatively contraindicated, like in the patients with Assistant Professor, Department of Anaesthesia, SICU and Pain Management. hyperkalemia or known family history of abnormal Abbasi Shaheed Hospital, Karachi Medical and Dental 1,2 cholinesterase enzyme activity . In addition, College, Cell # 03002411812 Email:[email protected] rocuronium being monoquatnary amino steroidal 79 Annals Abbasi Shaheed Hospital & Karachi Medical & Dental College Syeda Asma Khalid, Syed Hamid Ali, Sadqa Aftab, Waqar H. Kazmi drug, does not cross placenta therefore can safely lar dysfunction; it does not cause haemodynamic be used in obstetrical surgeries where risk of instability. The circulatory factor that determines 3-5 regurgitation requires rapid sequence induction . the intravenous anaesthetic etomidate proportionally effects the distribution of rapid acting muscle relax- The most popular hypnotic agents for RSI in ant; hence supporting the better intubating condition emergency cases in South Asia have been intrave- in shortest period of time for rapid sequence induc- nous thiopental sodium, ketamine, propofol and tion13-16 etomidate. Thiopental sodium, a short acting . thiobarbiturate, is considered a gold standard and The aim of this study is to determine the ef- has been widely used induction agent even for RSI fect on intubating conditions and haemodynamic re- in the past. However, it causes reduction in arterial sponse on intubation of two almost forgotten but blood pressure and reflex tachycardia in the pres- available and well proven different anaesthetic induc- ence of hypovolemia by abolishing the sympathetic tion agents, etomidate and thiopental sodium, with compensation with rapid induction. Regardless of a rapid acting muscle relaxant rocuronium in emer- its side effects thiopental sodium had long been gency department. used with pre-induction pharmacological optimiza- tion and intravenous fluids resuscitation. It sup- Patients and Methods presses neuronal activity, making it a useful This study was conducted in department of induction agent in haemodynamically stable pa- anaesthesia, Civil Hospital Karachi, Dow University tients with conditions that can elevate intracranial of Health Sciences and Abbasi Shaheed Hospital pressure including seizures, intracranial bleeding, or after approval from concerned ethics committee, de- trauma. However, its use as induction agent is now partmental permission and informed consents from limited due to unavailability in western part of world all the patients, from Nov 2011 to Dec 2012. This and the advent of newer hypnotics like propofol4-7, 9 . was a prospective quasi experimental study, in- Propofol, a phenol derivative, attenuates intuba- cluded 120 adult patients of either gender, aged be- tion response the most as compare to all other in- tween 18 and 80 years,having American Society of duction agents, but it can cause marked Anaesthesiologists(ASA) physical class I and II, un- hypotension and bradycardia with rapid induction in dergoing emergency surgeries, including general, compromised emergency situations4,14. Ketamine, a orthopaedic, plastic and neurosurgeries were allo- dissociative anaesthetic poorly attenuates the intu- cated randomly into two equal groups to receive ei- bation response, is favorable in situation where ther intravenous thiopental sodium (Group NTR) or marked cardiovascular decompensation is antici- etomidate (Group NER) as induction agent with pated after induction, provided the endogenous cat- muscle relaxant rocuronium for rapid sequence in- echolamine stores are not depleted as in critically duction. ill patients. On the contrary, it can cause hyperten- The patient with anticipated difficult laryngos- sion and marked tachycardia that can be deleteri- copy and intubation, allergy to any study medica- ous in hypertensive patients with left ventricular tions, receiving any other sedatives, acute upper air dysfunction2,4, 11-13 . way disease causing hyperreactive airway, pharyn- Etomidate, an imidazole compound, produces geal or laryngeal disease and having any neuromus- sedation and amnesia through α amino butyric acid cular dysfunction, severe sepsis were excluded (GABA)inhibitory neurotransmitter system. Its onset from the study. of action is rapid and comparable to propofol and The patients were randomly grouped using odd thiopental sodium that is 15-20 seconds. It has a and even method, patient with odd serial numbers superior profile in terms of cardiovascular stability were grouped to receive thiopental sodium with even when used in patients with severe left ventricu- Volume No. 19 (2), December 2014 80 Two Forgotten Induction Agents; Etomidate versus Thiopental Sodium with Rocuronium for Rapid Sequence Induction rocuronium while patient on even serial were 18 patients which had thiopental sodium as the in- grouped in to have etomidate and rocuronium for duction agent NTR (p=0.002), shown in Fig 1.The RSI. The anaesthetists, who intubated and as- vocal cords seen open in statistically significant pa- sessed the effect of drugs in terms of intubating tients on laryngoscopy, were 56 patients in NER condition and haemodynamics, were more than versus 38 patients in the other group (p=0.036) three year in experience and were blinded for the whereas in group NTR 8 and 12 patients had clos- study drugs. The primary investigator prepared the ing and moving vocal cords respectively at the time anaesthetic drugs and ensured the blinding with of intubation (Fig. 2). No patient from either group screen from intubating anaesthetist. All patients had had severe coughing and bucking. However 12 pa- standard monitoring including non-invasive blood tients in group NTR showed mild coughing versus 4 pressure, SpO2, ECG, capnography and tempera- patients in the group NER. Slight diaphragmatic ture monitoring. Baseline blood pressure, heart rate movement was also noticed in 26 patients which were noted in all the patients. was higher than found in group NER (p=0.007), (Table 2.). There was statistically significant differ- Group NTR was given intravenous analgesia In- ence in the mean of addition of all the scores i.e. jection Nalbuphine 0.1 mg/kg,