Administrative Policy and Procedure Policy Number:

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1 Administrative Policy and Procedure Policy Number: Subject: Sedation Page: 1 of 7 Effective: March 3, 1997 Revised: September 18, 2009 Approved: Signed by Kathy Guyette, VP and Chief Nursing Offcier on 9/18/2009 and orginal filed in Adminsitration. PURPOSE: Signed by Alan Baumgarten, MD., Chief of Staff on 9/18/2009 This policy seeks to establish minimum requirements for administering and monitoring sedation for all patients throughout Mission Hospitals. This Administrative Policy of Mission Health System, Inc. ("Mission") is applicable to Mission Hospitals, Memorial and St. Joseph campuses, the Asheville Surgery Center and other locations where services of the hospital are being provided. Site specific sedation guidelines may be more, but not less restrictive than the hospital guidelines, and must conform to requirements that patients with the same health status receive a comparable level of care throughout Mission Hospitals. These standards are intended for patients undergoing a diagnostic or therapeutic procedure. This policy is applicable to all patients undergoing procedures with the intent to receive sedation. DEFINITIONS: 1. Anxiolysis A drug-induced state using medications administered by oral and IM routes during which patients respond normally to verbal commands. The guidelines for Sedation outlined in this policy do not apply to anxiolysis. 2. Moderate Sedation/Analgesia (Conscious Sedation) A drug-induced depression of consciousness during which patients respond purposefully to verbal commands, either alone or accompanied by light tactile stimulation. No interventions are required to maintain a patent airway, and spontaneous ventilation is adequate. Cardiovascular function is usually maintained. 3. Deep Sedation/Analgesia A drug induced depression of consciousness during which patients cannot be easily aroused but respond purposefully after repeated or painful stimulation. The ability to independently maintain ventilatory function may be impaired. Patients may require assistance in maintaining a patent airway and spontaneous ventilation may be inadequate. Cardiovascular function

2 Policy # SEDATION Page 2 of 7 is usually maintained. 4. Anesthesia Consists of general anesthesia and spinal or major regional anesthesia. It does not include local anesthesia. General anesthesia is a drug induced loss of consciousness during which patients are not arousable, even by painful stimulation. The ability to independently maintain ventilatory function is often impaired. Patients often require assistance in maintaining a patent airway, and positive pressure ventilation may be required because of depressed spontaneous ventilation or drug induced depression of neuromuscular function. Cardiovascular function may be impaired. 5. Proceduralist The person qualified to perform the procedure. This person may be a physician, midlevel provider, or others privileged to perform an invasive procedure or may be a technologist or other personnel qualified to perform the procedure for noninvasive procedures such as chest radiographs, nuclear medicine scans, ultrasound examinations, or MRI s. 6. Sedationist The physician or advanced practitioner privileged to perform the sedation. 7. Monitor A person qualified to monitor and respond appropriately to the patient's response to medication and assist in any supportive or resuscitative measures required. The monitor will not engage in any tasks that would compromise continuous patient monitoring. EXCLUSIONS: 1. This policy is not intended to address situations in which an anesthesiologist or nurse anesthetist is engaged in the administration of anesthesia/sedation. 2. This policy does not apply to sedation used to secure an airway, for ventilatory management, for pain control, or when sedation is used as chemical restraint in the psychiatric patient. LOCATION: Moderate Sedation may be administered in the following primary locations: Emergency Department, Intensive Care Units, Operating Rooms, Asheville Surgery Center, Radiology Department, Cardiac Cath Lab, Echo Lab, Endoscopy Department including mobile endoscopy, and Pediatrics, Pediatric Outpatient, Pediatric Adolescent Unit, Pediatric Intensive Care Unit, Neonatal Intensive Care Unit and Trauma Care Unit. Secondary locations may be used when the personnel and equipment needed to perform moderate sedation (as outlined in this policy) are present. Deep Sedation may be administered in adult and pediatric Intensive Care Units, Neonatal Intensive Care Unit, Pediatric Outpatient, Trauma Care Unit, Cardiac Cath Lab, Radiology, and in the

3 Policy # SEDATION Page 3 of 7 Emergency Department. PRIVILEGING AND SKILL COMPETENCY: Practitioners responsible for the administration of moderate and deep sedation will be privileged through the Medical Staff Credentials Committee. This committee, in consultation with Anesthesiology Clinical Services, establishes the credentialing process and criteria. The RN monitoring the patient during procedures requiring moderate sedation will have BLS certification and will demonstrate satisfactory completion of the sedation learning module. The RN monitoring the patient during procedures requiring deep sedation will have ACLS certification and will demonstrate satisfactory completion of the sedation learning module. The person monitoring the pediatric patients during procedures requiring moderate or deep sedation will be a Pediatric Advanced Life Support (PALS) and/or Emergency Nurse Pediatric Course (ENPC) certified RN and will demonstrate successful completion of the pediatric sedation learning module. PATIENT SELECTION: 1. The need for any short term, therapeutic, diagnostic, or surgical procedure and subsequent use of sedation will remain under the individual practitioner's practice direction. 2. There must be a documented pre-procedure evaluation of the patient prior to any short term therapeutic, diagnostic, or surgical procedure requiring sedation. A. A medical history and physical must be performed and documented in the medical record prior to procedure or sedation. Minimal content required includes: Examination specific to procedure being performed. Indications/symptoms for procedure. Auscultation of heart and lungs. Airway assessment Previous anesthesia/sedation history. Components of airway assessment include: Look for large incisors, large tongue, beard or facial trauma Evaluate 3 finger mouth opening, 3 finger from chest to neck and 2 fingers thyroid to floor of mouth Mallampati classification Obstruction Neck Mobility B. There is to be a reevaluation immediately prior to administration of intravenous medications to determine that the patient is at this time an appropriate candidate for

4 Policy # SEDATION Page 4 of 7 sedation. 3. Practitioners are encouraged to consult with a member of the Anesthesiology Clinical Service when there is a question regarding the appropriate delivery of sedation. INFORMED CONSENT: Informed consent for any short term therapeutic, diagnostic or surgical procedure in which moderate or deep sedation is to be employed will be signed, dated, and timed and will include the risks/benefits/alternatives of sedation as appropriate. The informed consent should read "(Procedure) with sedation". MANAGEMENT: Moderate Sedation 1. The minimum number of personnel for employing moderate sedation shall be two. The Proceduralist is the person qualified to perform the procedure. The Sedationist is the physician or advanced practitioner privileged to perform moderate sedation. The Sedationist selects and orders the medications to produce sedation. If the Proceduralist is also the Sedationist, then a monitor is needed. If the Sedationist is not the Proceduralist, then a monitor is not necessary. The monitor is the person qualified to monitor and respond appropriately to the patient s response to medication and assist in any supportive or resuscitative measures required. The monitor will not engage in any tasks that would compromise continuous patient monitoring. The Sedationist and the monitor will be available to the patient from the time of administration of sedation until recovery or until the care of the patient is transferred to personnel performing recovery care. 2. The following minimum equipment must be present and ready for use in the room where moderate sedation is being administered. A. Oxygen. B. Suction. C. Emergency airway equipment. D. Cardiac monitor if indicated by practitioner. E. Noninvasive blood pressure monitor or manual blood pressure cuff applied. F. Pulse oximeter applied with audible variable pitch pulse tone and low threshold alarm. G. Code cart with defibrillator must be located in close proximity to the procedure/sedation area. H. Reversal agents. 3. All patients receiving IV moderate sedation must have a patent IV with continuous administration of IV fluids per practitioner order. Patent saline or heparin locks (INTs) are acceptable for patients with contraindications to IV fluids. IV fluid for resuscitation should be readily available. The need for IV access in patients receiving sedation by any other route of administration shall be determined by the practitioner.

5 Policy # SEDATION Page 5 of 7 4. The patient's NPO status will be assessed. The recommended guidelines for nonurgent/non emergent procedures is the patient be NPO for a minimum of two (2) hours for clear liquids, six (6) hours for light meal (nonfat, nonmeat, example: toast), and eight (8) hours for other solid food. Infants may have breast milk up to four (4) hours or infant formula up to six (6) hours prior to procedure. Deep Sedation. 1. The minimum number of personnel for employing deep sedation shall be two. The Proceduralist is the person qualified to perform the procedure. The Sedationist is the physician privileged to perform deep sedation. The Sedationist selects and orders the medications required for deep sedation. If the Proceduralist is also the Sedationist, then a monitor must be present. If the Sedationist is not the Proceduralist, then no monitor is required. The monitor is the person competent to monitor and respond appropriately to the patient s response to medication and assist in any supportive or resuscitative measures required. The monitor will not engage in any tasks that would compromise continuous patient monitoring. The Sedationist and the monitor will be available to the patient from the time of administration of sedation until recovery or until the care of the patient is transferred to personnel performing recovery care. When Propofol is being administered for deep sedation, the minimum number of personnel shall be three. If the Sedationist is not the Proceduralist, then one additional monitor is required. The monitor is the person competent to monitor and respond appropriately to the patient s response to medication and assist in any supportive or resuscitative measures required. The monitor will not engage in any tasks that would compromise continuous patient monitoring. If the Sedationist is also the Proceduralist, then two additional persons are required. One monitor is the person competent to monitor and respond appropriately to the patient s response to medication and assist in any supportive or resuscitative measures required. The monitor will not engage in any tasks that would compromise continuous patient monitoring. A second monitor capable of assistance in maintaining a patent airway and supporting respirations in case ventilatory function is impaired. The second monitor may be another physician or may be a respiratory therapist. 2. The following minimum equipment must be available for use where deep sedation is being administered. A. Oxygen. B. Suction. C. Emergency airway equipment. D. Cardiac monitor applied. E. Noninvasive blood pressure monitor or manual blood pressure cuff applied. F. Pulse oximeter applied with audible variable pitch pulse tone and low threshold alarm. G. Code cart with defibrillator must be located in close proximity to the

6 Policy # SEDATION Page 6 of 7 procedure/sedation area. H. Reversal agents. 3. All patients receiving IV deep sedation must have a patent IV with continuous administration of IV fluids per practitioner order. Patent saline or heparin locks (INTs) are acceptable for patients with contraindications to IV fluids. IV fluid for resuscitation should be readily available. The need for IV access in patients receiving sedation by any other route of administration shall be determined by the practitioner. 4. The patient's NPO status will be assessed. The recommended guidelines for nonurgent/non emergent procedures is the patient be NPO for a minimum of two (2) hours for clear liquids, six (6) hours for light meal (nonfat, nonmeat, example: toast), and eight (8) hours for other solid food. Infants may have breast milk up to four (4) hours or infant formula up to six (6) hours prior to procedure. PROCEDURE MANAGEMENT: 1. A standardized sedation flow sheet will be completed by the monitor for all patients receiving moderate or deep sedation. 2. Documentation on the sedation flow sheet must include: A. Verification that informed consent is signed. B. Weight. C. NPO status. D. Prior adverse drug reactions including allergies. E. Premedication. F. Beginning and end time of procedure. G. Baseline blood pressure, pulse, respiratory rate, oxygen saturation on room air (unless the patient is receiving oxygen preprocedure), level of consciousness. H. Name, dose, route, and time of all drugs given. I. Patient response to all medications given. J. Oxygen delivery. K. Type and amount of IV fluids (if administered). L. Any adverse drug reactions or significant responses; management and outcome of these events. 3. Minimum monitoring will include: blood pressure, pulse, respiratory rate, oxygen saturation, level of consciousness (cardiac monitoring required for deep sedation). Minimum monitoring must be documented on the flow sheet at least every ten minutes during the procedure for the adult patient; document on the flow sheet at least every five minutes during the procedure for the pediatric patient. When frequent monitoring of blood pressure and pulse interrupt the procedure, those measures will be waived intraprocedure. POST PROCEDURE MANAGEMENT FOR MODERATE OR DEEP SEDATION: 1. Patients who receive sedation will be monitored post procedure. They will be considered recovered when monitoring shows a return to safe physiological and psychological levels. An equivalent to the Aldrete Scoring System will be used.

7 Policy # SEDATION Page 7 of 7 2. Any person receiving a reversal agent must be observed for one hour after the last dose of reversal agent. 3. Inpatient monitoring and documentation: A. Blood pressure, pulse, respirations, oxygen saturation, and level of consciousness at least every fifteen minutes. B. Observation of any post procedure complications, management of those events, and patient response. C. Name, dose, time, route and response of any medications given in the post procedure period. C. Discharge summary and verbal report to nurse caring for patient on patient care unit. Include pre-procedure vital signs and level of consciousness, any problems encountered during or post procedure, total medications given, IV fluid total, and status of IV. 4. Outpatient monitoring and documentation: A. Blood pressure, pulse, respiration, oxygen saturation, and level of consciousness at least every fifteen minutes. B. Observation of any post procedure complications, management of those events and patient response. C. Name, dose, time, route and response of any medications given in the post procedure period. D. Verbal and written discharge instructions to patient and responsible adult accompanying patient and driving them home to include restrictions following sedation. PERFORMANCE IMPROVEMENT: The Chairperson or designee of the Anesthesiology Clinical Service is responsible to oversee the monitoring and evaluation of sedation use. The following data is gathered for review following the administration of sedation: > Unplanned intubation > Unplanned admission or transfer to higher level of care > Administration of reversal agent > Drop in oxygen saturation to less than 92% not responsive rapidly to oxygen therapy > Nausea and vomiting > Unable to complete procedure > Achieved sedation level deeper than intent > Failure to comply with documentation requirements

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9 Physician: Procedure: Date/Time: Practitioner Intent: Minimal/Moderate Sedation Deep Sedation DO NOT WRITE IN MARGIN This section must be completed by Practitioner Performing Procedure H & P documented No history of complications with previous anesthetics/sedation Indications for Procedure documented Auscultation of Heart and Lungs No history of sleep apnea Airway assessment: Look for large incisors, large tongue, beard/moustache, or facial trauma None found Specify findings *Evaluate 3 finger mouth opening, 3 fingers from chin to neck, 2 fingers thyroid to floor of mouth Normal Specify findings * Mallampati classification 1 or 2 3 or 4 Obstruction None visible Specify findings Neck mobility Normal Specify findings * Not applicable for patients < 50 kg or 14 years of age DO NOT WRITE IN MARGIN Re-evaluation by Practitioner prior to administration of medications I have determined this patient is an appropriate candidate for sedation. Practitioner Signature DO NOT WRITE IN MARGIN MSJ Mission Hospital, Inc. Asheville, NC Sedation Evaluation Sheet DRAFT/PROOF DATE: REVISIONS needed APPROVED by: Owner Sponsoring Phys(Required) Pharmacy CDCChairman (if Appl.) Nurse Council (if Appl.) PLEASE Interoffice REVISIONS or APPROVAL to Forms Coordinator - HIM Dept. Thanks.

10 The LEMON examination of the airway has been validated (1) as a specific and sensitive predictor of a difficult intubation. The four characteristics of the Look exam are large incisors, large tongue, beard or moustache, and facial trauma with large incisors being the most predictive of difficult intubation. The exam is summarized below. (Fig 1 taken from reference 1) The exam is scored with one point for presence of each of the four Look criteria, one for each of the rule measurements not reaching the minimum required, one for a Mallampati score of 3 or 4, one for presence of obstruction and one for limited neck mobility. Zero is scored if the component is absent or

11 cannot be evaluated. The maximum score is 10, the minimum, zero. Any score above 3 is highly predictive of a difficult intubation. With respect to pediatric airway examination - E: evaluate the rule is not valid in children; nor is M: the Mallampati classification. The LON version of the LEMON is still pertinent and should be documented. Scoring has not been validated in the pediatric patient. 1. Can an airway assessment score predict difficulty at intubation in the emergency department? M J Reed 1, M J G Dunn 1, D W McKeown, Emergency Medicine Journal 2005;22:99-102

12 Downloaded from emj.bmj.com on 22 October 2009 Can an airway assessment score predict difficulty at intubation in the emergency department? M J Reed, M J G Dunn and D W McKeown Emerg. Med. J. 2005;22; doi: /emj Updated information and services can be found at: References Rapid responses alerting service These include: This article cites 14 articles, 7 of which can be accessed free at: 2 online articles that cite this article can be accessed at: 4 rapid responses have been posted to this article, which you can access for free at: You can respond to this article at: Receive free alerts when new articles cite this article - sign up in the box at the top right corner of the article Topic collections Articles on similar topics can be found in the following collections Surgical diagnostic tests Dentistry and oral medicine Resuscitation (6048 articles) (7111 articles) (2452 articles) Notes To order reprints of this article go to: To subscribe to Emergency Medicine Journal go to:

13 Downloaded from emj.bmj.com on 22 October ORIGINAL ARTICLE Can an airway assessment score predict difficulty at intubation in the emergency department? M J Reed, M J G Dunn, D W McKeown... Emerg Med J 2005;22: doi: /emj See end of article for authors affiliations... Correspondence to: Dr M J Reed, Emergency Department, Royal Infirmary of Edinburgh, 51 Little France Crescent, Edinburgh EH16 4SA, UK; mattreed1@hotmail.com Accepted for publication 9 December Aim: To assess whether an airway assessment score based on the LEMON method is able to predict difficulty at intubation in the emergency department. Methods: Patients requiring endotracheal intubation in the resuscitation room of a UK teaching hospital between June 2002 and September 2003 were assessed on criteria based on the LEMON method. At laryngoscopy, the Cormack and Lehane grade was recorded. An airway assessment score was devised and assessed. Results: 156 patients were intubated during the study period. There were 114 Cormack and Lehane grade 1 intubations, 29 grade 2 intubations, 11 grade 3 intubations, and 2 grade 4 intubations. Patients with large incisors (p,0.001), a reduced inter-incisor distance (p,0.05), or a reduced thyroid to floor of mouth distance (p,0.05) were all more likely to have a poor laryngoscopic view (grade 2, 3, or 4). Patients with a high airway assessment score were more likely to have a poor laryngoscopic view compared with those patients with a low airway assessment score (p,0.05). Conclusions: An airway assessment score based on criteria of the LEMON method is able to successfully stratify the risk of intubation difficulty in the emergency department. Patients with a poor laryngoscopic view (grades 2, 3, or 4) were more likely to have large incisors, a reduced inter-incisor distance, and a reduced thyroid to floor of mouth distance. They were also more likely to have a higher airway assessment score than those patients with a good laryngoscopic view. T here is a growing trend in the UK for advanced airway management to be performed in the emergency department (ED) resuscitation room by ED clinicians, rather than anaesthetists. The need for tracheal intubation in the ED may be unpredictable and is often promptly required. When compared with the same procedure performed in the operating room, a higher incidence of airway management failure has been suggested. 1 Some 0.01% of patients intubated electively will have an airway management failure compared with an ED rescue cricothyrotomy rate of 1% in the pilot phase of the National Emergency Airway Registry (NEAR) studies. 1 It is suggested that patients intubated in the ED have poorer views on laryngoscopy measured by higher Cormack and Lehane scores. 2 3 The historical information, physical examination findings, and radiological features associated with a difficult airway are well established. Proposed airway assessment scales vary from the simple, which often fail to address the many factors associated with a difficult airway, to the complex, which are impractical as a clinical tool. None have been shown to be accurate in predicting airway management problems, and none have been assessed in the ED setting. The physical characteristics associated with difficult intubation include obesity, head and neck movement, jaw movement, 4 6 receding mandible, buck teeth (long upper incisors), Mallampatti scores, maxillary incisor characteristics, 7 male sex, 8 age 40 59, 8 decreased mouth opening, shortened thyromental distance, and short neck. 7 Multivariate analysis has been used to quantify the relative role of each of these physical characteristics An assessment system that objectively measures factors associated with a difficult intubation in the resuscitation room needs to be simple to perform, suitable to perform on obtunded and/or non-compliant patients, and easily remembered. All of the above systems fail to be suitable when applied in an ED setting. The US National Emergency Airway Management Course has addressed this issue by devising the LEMON method (fig 1). 1 This assessment system includes most of the characteristics discussed above and has been adapted for use in a resuscitation room setting. The LEMON method has not however been validated as a reflection of difficult intubation in the ED. The aim of this study was therefore to assess whether an airway assessment score based on the LEMON method is able to predict difficulty at intubation in the ED. METHOD This was a prospective observational study conducted in the ED of a UK teaching hospital between June 2002 and September All patients who entered one of the department s resuscitation rooms underwent an airway assessment according to the LEMON method (fig 1). They were assessed on four look criteria, three evaluate criteria, the presence of airway obstruction, and neck mobility. Mallampatti class 13 was also recorded if possible. Only four of the seven look characteristics originally described in the LEMON method were assessed: abnormal facial shape was thought to be too subjective, protruding teeth is duplicated by the large incisor characteristic, and false teeth is often difficult to assess adequately. If intubation was performed as part of the patient s routine clinical management, the grade of intubation was recorded according to Cormack and Lehane scores. 14 For the purposes of this study, an easy intubation was defined as a Cormack and Lehane laryngoscopy grade 1 view, and a difficult intubation was defined as a Cormack and Lehane laryngoscopy grade 2, 3, or 4 view (see Discussion). If an initial intubation attempt was unsuccessful, the grade of laryngoscopy on the eventual successful attempt was used to define the difficulty of intubation.

14 Downloaded from emj.bmj.com on 22 October Reed, Dunn, McKeown L Look externally Look at the patient externally for characteristics that are known to cause difficult laryngoscopy, intubation or ventilation. E Evaluate the rule In order to allow alignment of the pharyngeal, laryngeal and oral axes and therefore simple intubation, the following relationships should be observed. The distance between the patient's incisor teeth should be at least 3 finger breadths (3), the distance between the hyoid bone and the chin should be at least 3 finger breadths (3), and the distance between the thyroid notch and the floor of the mouth should be at least 2 finger breadths (2) = Inter-incisor distance in fingers. 3 2 = Hyoid mental distance in fingers. 3 = Thyroid to floor of mouth in fingers. Figure 1 The LEMON airway assessment method. M Mallampati The hypopharynx should be visualized adequately. This has been done traditionally by assessing the Mallampati classification. The patient is sat upright, told to open the mouth fully and protrude the tongue as far as possible. The examiner then looks into the mouth with a light torch to assess the degree of hypopharynx visible. In the case of a supine patient, Mallampati score can be estimated by getting the patient to open the mouth fully and protrude the tongue and a laryngoscopy light can be shone into the hypopharynx from above. Class I: soft palate, uvula, fauces, pillars visible Class II: soft palate, uvula, fauces visible Class III: soft palate, base of uvula visible Class IV: hard palate only visible O Obstruction? Any condition that can cause obstruction of the airway will make laryngoscopy and ventilation difficult. Such conditions are epiglottis, peritonsillar abscesses and trauma. N Neck mobility This is a vital requirement for successful intubation. It can be assessed easily by getting the patient to place their chin down onto their chest and then to extend their neck so they are looking towards the ceiling. Patients in hard collar neck immobilization obviously have no neck movement are therefore harder to intubate. An airway assessment score was calculated as follows. The number of positive look criteria was calculated. One point was added for each unfavourable evaluate criteria (mouth opening less than three finger breadths, hyo-mental distance less than three finger breadths, or a thyro-hyoid distance less than two finger breadths). One point was also added for a Mallampatti score of 3 or more, for an obstructed airway, and for poor neck mobility. If a test could not be performed the patient received a score of zero for that criterion. The maximum airway assessment score possible was therefore 10 and the minimum zero. All data were entered on a form and completed forms were collected for data entry and analysis using Microsoft Excel. Fisher s exact test was used to compare categorical variables and Student s t test for parametric data. Spearman s rank sum test was used to assess correlation between categorical variables. Significance was defined as p,0.05. RESULTS Between June 2002 and September 2003, 156 patients who were intubated in the ED were entered into the study. This comprised 88% of the 177 patients undergoing intubation in the department during this period. Patients who were lost from the study did not have a formal airway assessment performed at the time of intubation. All 156 patients were successfully intubated in the ED. Altogether 114 patients were characterised as Cormack and Lehane grade 1 and 42 were classed as Cormack and Lehane grades 2, 3, or 4 (grade 2 = 29, grade 3 = 11, and grade 4 = 2). Table 1 compares the characteristics of patients with an easy intubation (grade 1) compared with those with a difficult intubation (grades 2, 3, and 4). There was no significant difference in the sex ratios (M/F) between the two groups (75/39 compared with 32/10, p = 0.25, NS). There was also no difference in mean age between the two groups (53.8 years compared with 55.7 years, p = 0.86, NS). Of the three look criteria of the LEMON method, only patients with large incisors (p,0.001) were more likely to have a difficult intubation (grade 2, 3, or 4). There was no difference in intubation grade in patients with facial trauma (p = 1.0, NS), a beard or moustache (p = 0.49, NS), or a large tongue (p = 0.49, NS). Of the three evaluate criteria, both a reduced inter-incisor distance (p,0.05) and a reduced thyroid to floor of mouth distance (p,0.05) were associated with a difficult intubation. There was no significant difference in intubation grade in patients with a reduced hyoid to chin distance (p = 0.34, NS) however 45.8% of patients in the

15 Downloaded from emj.bmj.com on 22 October 2009 Can an airway assessment score predict difficulty at intubation? 101 Table 1 Summary of results Characteristic Easy intubation group Number Difficult intubation group Number p Value Number of patients Sex ratio (M/F) 75/ / NSÀ Male percentage Mean (SD) Mean (SD) Age 53.8 (23.2) (18.7) NS` Look % % Facial trauma NSÀ Large incisors ,0.001 *À Beard or moustache NSÀ Large tongue NSÀ Evaluate % % Incisor distance ,0.05 *À Incisor distance, Hyoid / mental dist NSÀ Hyoid / mental dist, Thyroid to mouth ,0.05*À Thyroid to mouth, Mallampatti % % Grade 1 or NSÀ Grade 3 or Obstruction % % Obstructed airway NSÀ Neck mobility % % In collar/limited NSÀ Full and free *Significance accepted at the level of 0.05 = 5%; NS, non-significant. ÀFisher s exact test (two tailed); `Student s t test (two tailed). difficult intubation group had a reduced hyoid to chin distance compared with only 34.2% in the easy intubation group. There was also no significant association between an increased Mallampatti score, the presence of airway obstruction, or the presence of limited neck mobility and a difficult intubation. Patients with a difficult intubation were more likely to have an obstructed airway (14.3% versus 6.5%) and reduced neck mobility (28.6% versus 16.2%) although this did not reach significance. Table 2 and figure 2 compare the airway assessment scores for the two intubation difficulty groups. Patients in the difficult intubation group had a significantly greater airway assessment score compared with patients in the easy intubation group (p,0.05). There was also a positive correlation between airway assessment score and intubation grade Number of patients Airway score Easy intubation Difficult intubation Figure 2 Graph showing number of patients with each airway assessment score in both intubation difficulty groups. 6 7 Table 2 Airway assessment scores for the two intubation difficulty groups Easy intubation group Airway assessment score Difficult intubation group Number % Number % p Value Total Median IQ range p,0.05 *À *Significance accepted at the level of 0.05 = 5%. ÀFisher s exact test (two tailed). (r = 0.38, p,0.001). Median airway assessment score for the easy intubation groups was 1.0 (interquartile range 0 2.0) compared with 2.0 (interquartile range ) in the difficult intubation group. DISCUSSION This is the first published study that has attempted to validate the LEMON method in the ED population. We have shown that an airway assessment score based on the LEMON method is able to stratify the risk of intubation difficulty in this population. We have also shown that ED patients with certain airway characteristics are also more likely to have a poor laryngoscopic view. Patients with large incisors, a reduced mouth opening, and a reduced thyroid to floor of mouth distance are all more likely to have a poor view at laryngoscopy. Patients with a reduced hyoid to chin distance, airway obstruction, and reduced neck mobility all have a trend towards poor views, however these factors did not

16 Downloaded from emj.bmj.com on 22 October Reed, Dunn, McKeown Table 3 Proposed revised LEMON based airway assessment score Airway assessment score Points Number of positive unfavourable 0 4 points look criteria Mouth opening less than three finger 1 point breadths Hyo-mental distance less than three 1 point finger breadths Thyro-hyoid distance less than two 1 point finger breadths Presence of an obstructed airway 1 point Presence of poor neck mobility 1 point Total:maximum airway assessment score = 9, minimum = zero reach significance in this study. A study looking at a larger population may show that these factors are also associated with poor laryngoscopic views. This study has several limitations. The airway manager performing the LEMON assessment also performed the intubation procedure. This may have led to bias in the subsequent recording of the LEMON characteristics or intubation grade. To assess a large number of intubations, the study aimed to include all intubations carried out in the ED. This could have led to interobserver variability when recording the LEMON characteristics. For example, an inter-incisor distance is measured in finger breadths, which are in turn dependent on the person conducting the test. Other characteristics prone to subjectivity are those of the look assessment. Clearly the assessment of a rather vague term such as large incisors is highly subjective and is prone to significant interobserver variability. We do not deny that this is the case, however the LEMON method includes the assessment of such characteristics and is designed to be a quick and easy assessment tool. To include complex definitions for such characteristics would defeat the purpose of such a simple, easily remembered ED airway assessment tool. Three look characteristics originally described in the LEMON method were removed for this study (see Methods) for similar reasons. We have defined intubation difficulty based on scores at laryngoscopy. We recognise that laryngoscopic view may be a separate issue to intubation difficulty. Other factors such as the number of separate laryngoscopy attempts made, the length of laryngoscopy attempts, and the number and seniority of airway managers involved have also been described as markers of a difficult intubation. 12 We chose not to look at these other markers because of their many confounding factors (for example, operator experience), however they could be assessed in future studies. We have already shown in a previous study that the look, obstruction, and neck mobility components of the LEMON method are easily assessed in the resuscitation room population. 15 Evaluate criteria could only be fully assessed in 90% of the resuscitation room population and Mallampatti was even less easily assessed being possible in only 57% of patients. As we have shown that Mallampatti is both difficult to assess and a poor predictor of intubation grade in the ED, it probably has little place in an ED airway assessment score. Evaluate criteria are more easily assessed and seem to be predictive of a difficult intubation in the ED population. We suggest that a LEMON method based airway assessment score (table 3) based on four of the five criteria of the LEMON method (all except Mallampatti ), should be routinely used in the ED to highlight a potentially difficult airway. Use of this score would encourage airway managers to conduct a thorough systematic evaluation of the airway and to readily anticipate problems in its management. If difficulty was predicted early, then more senior help with advanced airway management could be sought. In conclusion, an airway assessment score based on criteria of the LEMON method is able to successfully stratify the risk of difficult intubation in the emergency department. Patients with a poor laryngoscopic view (grades 2, 3, or 4) were more likely to have large incisors, a reduced inter-incisor distance, and a reduced thyroid to floor of mouth distance. They were also more likely to have a higher airway assessment score than those patients with a good larygoscopic view. CONTRIBUTORS Matthew Reed: literature search, study design, interpretation of results, principal investigator, data entry, analysis and reporting of data, writing the paper. Mark Dunn: data collection, data entry, and revision of paper. Dermot McKeown: original idea, literature search, study design, project supervision, and revision of paper.... Authors affiliations M J Reed, M J G Dunn, Emergency Department, Royal Infirmary of Edinburgh, Edinburgh, UK D W McKeown, Anaesthetic Department, Royal Infirmary of Edinburgh Funding: none. Conflicts of interest: none declared. REFERENCES 1 Murphy MF, Walls RM. The difficult and failed airway. In: Manual of emergency airway management. Chicago: Lippincott Williams and Wilkins, 2000: MacKay CA, Terris J, Coats TJ. Prehospital rapid sequence induction by emergency physicians: is it safe? Emerg Med J 2001;18: Graham CA, Beard D, Oglesby AJ, et al. Rapid sequence intubation in Scottish urban emergency departments. Emerg Med J 2003;20: Wilson ME, Spiegelhalter D, Robertson JA, et al. Predicting difficult intubation. Br J Anaesth 1988;61: Frerk CM. Predicting difficult intubation. Anaesthesia 1991;46: Oates JDL, Macleod AD, Oates PD, et al. Comparison of two methods of predicting intubation difficulty. Br J Anaesth 1991;66: Rocke DA, Murray WB, Rout CC, et al. Relative risk analysis of factors associated with difficult intubation in obstetric anesthesia. Anesthesiology 1992;77: Rose DK, Cohen MM. The airway. Problems and prediction in patients. Can J Anaesth 1994;41: Tse JC. Rimm EB. Hussain A. Predicting difficult endotracheal intubation in surgical patients scheduled for general anesthesia: a prospective blind study, Anesth Analg 1995;81: el-ganzouri AR, McCarthy RJ, Tuman KJ, et al. Preoperative airway assessment: predictive value of a multivariate risk index. Anesth Analg 1996;82: Arne J, Descoins P, Fusciardi J, et al. Preoperative assessment for difficult intubation in general and ENT surgery: predictive value of a clinical multivariate risk index. Br J Anaesth 1998;80: Saghaei M, Safavi MR. Prediction of prolonged laryngoscopy. Anaesthesia 2001;56: Mallampatti SR, Gatt SP, Gugino LD, et al. A clinical sign to predict difficult intubation: a prospective study. Can Anaesth Soc J 1985;32: Cormack RS, Lehane J. Difficult intubation in obstetrics. Anaesthesia 1984;39: Reed MJ, Rennie LM, Dunn MJG, et al. Is the LEMON method an easily applied emergency airway assessment tool? European Journal of Emergency Medicine 2004;11:

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26 PPB-NCBH-86 Reviewed 7/1/05 Page 1 of 17 NORTH CAROLINA BAPTIST HOSPITALS POLICY AND PROCEDURE BULLETN PREPARED BY: CONTACT PERSON: SUBJECT: Dr. Jeff Kelly Dr. Raymond C. Roy Director of Surgical Services Administration of Sedatives and Analgesics by Non-Anesthesiologist Attending Physicians During Diagnostic and Therapeutic Procedures I. POLICY This policy refers to the administration of sedatives and/or analgesics under the medical direction of non-anesthesiologist attending physicians to patients undergoing invasive, constraining, or manipulative procedures in patient care areas outside of the Operating Room. II. PURPOSE The purpose of this policy is to ensure a comparable level of care for all patients receiving sedation and analgesia during procedure performance in patient care areas not routinely staffed by members of the Department of Anesthesiology and to improve patient outcomes in such areas. III. DEFINITIONS A. Minimal sedation (anxiolysis) a drug-induced state during which patients respond normally to verbal commands. Although cognitive function and coordination may be impaired, ventilatory and cardiovascular functions are unaffected. B. Moderate sedation/analgesia ( conscious sedation ) a drug-induced depression of consciousness during which patients respond purposefully to verbal commands, either alone or accompanied by light tactile stimulation. No interventions are required to maintain a patent airway, and spontaneous ventilation is adequate. Cardiovascular function is usually maintained. C. Deep sedation/analgesia a drug-induced depression of consciousness during which patients cannot be easily aroused, but respond purposefully following repeated or painful stimulation. The ability to independently maintain ventilatory function may be impaired. Patients may require assistance in maintaining a patent airway, and spontaneous ventilation may be inadequate. Cardiovascular function is usually maintained.

27 PPB-NCBH-86 Reviewed 7/1/05 Page 2 of 17 D. General anesthesia a drug-induced depression of consciousness during which patients are not arousable, even by painful stimulation. The ability to independently maintain ventilatory function is often impaired. Patients often require assistance in maintaining a patent airway, and positive pressure ventilation may be required because of depressed spontaneous ventilation or drug-induced depression of neuromuscular function. Cardiovascular function may be impaired. General anesthetic care is not covered by the terms of this policy and should only be administered by trained individuals with appropriate anesthesia credentials. While this policy is intended to be widely applicable, broad in scope, and fulfill the needs of most affected clinical areas, it may not be completely appropriate for some areas due to variables such as patient population, specific procedure demands, and/or attending physician experience/preference. In such circumstances, affected areas must develop an individual area-specific sedation/analgesia policy using this policy as their guide for minimal acceptable standards. Any area-specific policies so developed must contain strong evidence-based literature support justifying any deviations from this policy including, but not limited to (1) policy statements and/or practice guidelines independently developed by the appropriate national specialty organization and/or (2) satisfactory outcome data published in the appropriate specialty s national journal. Approval of such area-specific policies by both the Conscious Sedation Committee (which includes the Chairman of the Department of Anesthesiology) and the Chief of Professional Services will be required prior to their implementation. IV. POLICY APPLICABILITY This policy is applicable to the following areas and/or circumstances: A. Location: Sedation and analgesia is practiced in various areas within the Institution including, but not limited to the (1) Emergency Department, (2) Radiology Department, (3) MRI suite, (4) Bronchoscopy/Endoscopy suite, (5) Electrophysiology Laboratory, (6) Cardiac Catheterization suite, and (7) Clinical Ultrasound. B. Medications and dosages: Implementation of and compliance with the terms of this policy is mandatory whenever: (1) hourly dosages of a single sedative or analgesic agent exceed the age-specific thresholds summarized in Appendix 1 of this policy. (2) any combination of sedatives and analgesics in any dosage are administered. (3) nitrous oxide in concentrations up to 40% and mixed with oxygen is combined with another sedative and/or analgesic by another route of administration. This policy is not applicable to the following areas and/or circumstances: A. credentialed members of the Department of Anesthesiology; B. all areas designated by the institution as critical care areas; C. use of intravenous benzodiazepines for the acute treatment/control of tonic-clonic seizures; D. use of clinically appropriate doses of narcotics for analgesia in the setting of painful underlying medical conditions and/or perioperative surgical pain;

28 PPB-NCBH-86 Reviewed 7/1/05 Page 3 of 17 E. use of clinically appropriate doses of oral benzodiazepines for indications such as minimal sedation/anxiolysis, claustrophobia, seizure prophylaxis, delirium tremens treatment/prophylaxis, and/or hypnotic to aid sleep; F. use of nitrous oxide inhalation analgesia in concentrations up to 40% and mixed with oxygen in the absence of concurrent sedative and/or analgesic use by another route of administration; and G. general inpatient pediatric units covered by the Pediatric Sedation Service of the Department of Anesthesiology. Intravenous anesthetic induction agents (such as thiopental, methohexital, etomidate, ketamine, and propofol) and concentrations of nitrous oxide above 40% have such an extremely narrow margin of safety and/or unique side effect profile that this policy expressly forbids their administration for sedation and analgesia except as follows: A. use for rapid sequence intubation under the medical direction of Emergency Department attending physicians in a manner consistent with that area s policies and procedures; B. use of intravenous methohexital in the Electrophysiology Laboratory under the medical direction of Section on Cardiology attending physicians in a manner consistent with that area s policies and procedures; or C. ketamine administration in children as detailed in Appendix 1. V. PROCEDURE A. Facilities and equipment: Each clinical area where sedation and analgesia is administered, or where the recovery from sedation and analgesia occurs, must have at least the following minimal equipment present and in working order: (1) cardiac monitor with alarm capabilities. (2) pulse oximeter with alarm capabilities. (3) blood pressure measurement (oscillometric or auscultatory). (4) suction capabilities with appropriate devices, attachments, and tubing. (5) an oxygen source (either a 50 psi wall outlet or an E cylinder capable of delivering a 15 1/min inspiratory flow rate for at least 30 minutes). (6) a self-inflating reservoir bag-valve-mask system capable of both supporting ventilation as well as delivering > 90% oxygen concentration at the above inspiratory flow rates. An emergency cart containing basic/advanced airway equipment, a full complement of population-appropriate resuscitation drugs (including the reversal agents naloxone and flumazenil), and a monitor-defibrillator-pacemaker must be immediately available to resuscitate any patient suffering clinically significant cardiorespiratory compromise from sedative and/or analgesic administration. All areas must document that such resuscitation equipment has been checked and maintained on a regularly scheduled basis to ensure proper performance consistent with the current Medical Center Code Blue Plan. Each area should also have (a) current, ageappropriate resuscitation algorithms (ACLS and/or PALS), (b) a summary of age-appropriate naloxone and flumazenil doses, and (c) a mechanism to emergently mobilize either the

29 PPB-NCBH-86 Reviewed 7/1/05 Page 4 of 17 Department of Anesthesiology and/or the Medical Center code team to assist with resuscitative efforts (appendices 2 and 3). B. Personnel: The minimum number of health care providers attending the patient receiving sedation and analgesia shall be two, i.e., the licensed independent practitioner (LIP) (defined as the attending physician of record performing the procedure/diagnostic study) and a second designated, properly trained monitoring provider who is not involved in procedure performance. The LIP is responsible for the overall management of the patient receiving sedation and analgesia as a component of the planned procedure as well as for supervising the monitoring provider simultaneously attending the patient. The LIP will be credentialed in the appropriate administration of sedation and analgesia under the terms of Medical Center Policy PPB-MSS-01, Credentialing and Recredentialing of Non-Anesthesiologist Attending Physicians for Use of Sedation and Analgesia During Painful, Constraining, or Manipulative Procedures. The monitoring provider attending the patient during the procedure under sedation and analgesia is responsible for continuously monitoring and documenting at frequent intervals the patient s clinical and physiologic status. Such monitoring providers should fulfill no additional functions during procedure performance except for brief, minor, interruptible tasks in patients with stable sedation/analgesia levels and vital signs. Monitoring providers will be credentialed in the appropriate care of patients receiving sedation and analgesia using the North Carolina Baptist Hospital s Competency Assessment for Nurses Delivering Conscious Sedation credentialing tool. A licensed practical nurse (LPN) who satisfactorily fulfills the terms of this competency assessment may serve as the monitoring provider when directly supervised by an appropriately credentialed registered nurse (RN) who is in close physical proximity to the procedure/diagnostic study. C. Preprocedure history and physical examination: In compliance with medical staff rules and regulations, all patients undergoing procedures under sedation and analgesia must receive a preprocedure evaluation focusing on major organ systems to assess their current overall medical condition and determine if they are a suitable sedation/analgesia candidate. While components of this required preassessment may be delegated to appropriately trained lower level health care providers, the LIP is ultimately responsible for confirming the accuracy of all information so collected. Such responsibility must be documented by the LIP s signature in the preassessment area on page 1 of form , Sedative/Analgesic Administration for Diagnostic and Therapeutic Procedures. The preassessment history should include at least: (1) a review of any pertinent medical records as appropriate. (2) a brief past medical history and review of systems, with specific emphasis on the cardiovascular, respiratory, airway, and central nervous systems. (3) current medications (prescription, nonprescription, herbal supplements ).