OBJETIVOS: Avaliar o conhecimento médico sobre as técnicas de intubação e identificar as práticas mais realizadas. MÉTODOS: Estudo prospectivo, envolvendo três diferentes unidades de terapia intensiva de um hospital universitário: da anestesiologia (ANEST), da pneumologia (PNEUMO) e do pronto socorro (PS). Todos os médicos que trabalham nessas unidades e que concordaram em participar do estudo, responderam um questionário contendo dados demográficos e questões sobre intubação orotraqueal. RESULTADOS: Foram obtidos 85 questionários (90,42% dos médicos). ANEST teve maior média de idade (p = 0,001), com 43,5% sendo intensivistas. Foi referido uso da associação hipnótico e opióide (97,6%) e pré oxigenação (91,8%), mas apenas 44,6% referiram utilização de coxim suboccipital, sem diferença entre as UTIs. Na ANEST, referiu-se maior uso de bloqueador neuromuscular (p < 0,000) e maior cuidado com estômago cheio (p = 0,002). O conhecimento sobre sequência rápida foi restrito (nota média - 2,20 ± 0,89, com p = 0,6 entre as unidades de terapia intensiva. A manobra de Sellick era conhecida por (97,6%), mas 72% usaram-na inapropriadamente. CONCLUSÕES: O conhecimento médico sobre intubação orotraqueal em terapia intensiva não é satisfatório, mesmo entre profissionais qualificados para tal procedimento. É necessário avaliar se há concordância entre as respostas dos questionários e as práticas clínicas efetivamente adotadas.
Intubação orotraqueal; Conhecimento; Terapia intensiva
OBJECTIVES: To assess the physician’s knowledge on intubation techniques and to identify the common practices. METHODS: This was a prospective study, involving three different intensive care units within a University hospital: Anesthesiology (ANEST), Pulmonology (PULMO) and Emergency Department (ED). All physicians working in these units and consenting to participate in the study completed a questionnaire with their demographic data and questions on orotracheal intubation. RESULTS: 85 completed questionnaires were retrieved (90.42% of the physicians). ANEST had the higher mean age (p=0.001), being 43.5% of them intensivists. The use of hypnotic and opioid association was reported by 97.6%, and pre-oxygenation by 91.8%, but only 44.6% reported sub-occipital pad use, with no difference between the ICUs. On ANEST an increased neuromuscular blockade use was reported (p<0.000) as well as increased caution with full stomach (p=0.002). The rapid sequence knowledge was restricted (mean 2.20 ± 0.89), p=0.06 between the different units. The Sellick maneuver was known by 97.6%, but 72% used it inappropriately. CONCLUSIONS: Physicians knowledge on orotracheal intubation in the intensive care unit is unsatisfactory, even among qualified professionals. It is necessary to check if the responses to the questionnaire and actual clinical practices agree.
Orotracheal, intubation; Knowledge; Intensive care
Orotracheal intubation: physician's knowledge assessment and clinical practices in intensive care units
IMedical Graduation Student of Escola Paulista de Medicina da Universidade Federal de São Paulo UNIFESP São Paulo (SP), Brazil
IIPhD, Physician of Disciplina de Emergências Clinicas da Universidade Federal de São Paulo UNIFESP São Paulo (SP), Brazil
IIIPhysician of Disciplina de Pneumologia da Universidade Federal de São Paulo UNIFESP São Paulo (SP), Brazil
IVNurse of the Intensive Care Unit of Disciplina de Anestesiologia, Dor e Terapia Intensiva da Universidade Federal de São Paulo UNIFESP São Paulo (SP), Brazil
VNurse of the Intensive Care Unit of Disciplina de Emergências Clínicas da Universidade Federal de São Paulo UNIFESP São Paulo (SP), Brazil
VINurse of the Intensive Care Unit of Disciplina de Pneumologia da Universidade Federal de São Paulo UNIFESP São Paulo (SP), Brazil
VIIMSc, Physician of the Intensive Care Sector of Disciplina de Anestesiologia, Dor e Terapia Intensiva da Universidade Federal de São Paulo UNIFESP São Paulo (SP), Brazil
VIIIPhD, Adjunct Professor to Disciplina de Anestesiologia, Dor e Terapia Intensiva da Universidade Federal de São Paulo UNIFESP São Paulo (SP), Brazil.Received from the Universidade Federal de São Paulo UNIFESP São Paulo (SP), Brazil
Author for correspondence
OBJECTIVES: To assess the physician's knowledge on intubation techniques and to identify the common practices.
METHODS: This was a prospective study, involving three different intensive care units within a University hospital: Anesthesiology (ANEST), Pulmonology (PULMO) and Emergency Department (ED). All physicians working in these units and consenting to participate in the study completed a questionnaire with their demographic data and questions on orotracheal intubation.
RESULTS: 85 completed questionnaires were retrieved (90.42% of the physicians). ANEST had the higher mean age (p=0.001), being 43.5% of them intensivists. The use of hypnotic and opioid association was reported by 97.6%, and pre-oxygenation by 91.8%, but only 44.6% reported sub-occipital pad use, with no difference between the ICUs. On ANEST an increased neuromuscular blockade use was reported (p<0.000) as well as increased caution with full stomach (p=0.002). The rapid sequence knowledge was restricted (mean 2.20 ± 0.89), p=0.06 between the different units. The Sellick maneuver was known by 97.6%, but 72% used it inappropriately.
CONCLUSIONS: Physicians knowledge on orotracheal intubation in the intensive care unit is unsatisfactory, even among qualified professionals. It is necessary to check if the responses to the questionnaire and actual clinical practices agree.
Keywords: Orotracheal, intubation; Knowledge; Intensive care
Orotracheal intubation (OTI) is considered one of the most important potential life savers procedures. Its main indication is for situations with impaired airways patency. As with any other procedure, OTI may have risks and complications,(1-5) preventable if performed with correct technique. Among the main complications, esophageal intubation may cause hypoxemia, hypercapnia, and death; selective intubation, may cause the non-ventilated lung atelectasis, or barotraumas; and trauma involving upper airways, cervical spine, teeth, heart arrhythmias and others. OTI is a routine procedure in intensive care units (ICUs), being evident the need for correct technique intubations. For this, it is important to know the intubation techniques, which should strictly comply with a protocol attending to all its steps.
In order to minimize risks, the physician should perform a patient's initial evaluation regarding consciousness level, pulmonary aspiration risk factors and difficult airway. It is important to highlight that all ICU patients, as a matter of principle, should be considered as in danger of aspiration, and thus undergo rapid sequence intubation.(6-9) In this, the procedure is made with more agility than classically, with an opioid administration together with an hypnotic, followed by a fast acting neuromuscular blocker (NMB), mandatory Sellick maneuver, and no assisted ventilation use.(10-12)
Several studies on medical OTI practices evaluated how intubations are conducted, showing lack of OTI techniques standardization, wide inter-individual variability on emergency(13), anesthesiology(14,15) and intensive care(1) practice settings. Regarding the intensive care intubation practice, some articles specifically evaluating intubation complications were also found.(1,16,17) In addition to this practical procedure evaluation, some authors also evaluated the physician's knowledge, using questionnaires.(18-20) Morris et al.(18) and Thwaites et al.(19) showed a considerable range of practices for rapid sequence intubation among anesthesiologists. The same was seen for anesthesiology residents.(20) Other articles showed the correct Sellick maneuver knowledge to be scarce.(21-23) In the reviewed literature, no articles were found on intensive care theoretical knowledge.
This study was proposed aiming to evaluate the physicians' knowledge on intubation techniques, and to identify the most common procedures used in ICUs.
After approval by the Hospital São Paulo's Ethics Committee, a prospective study was conducted involving physicians who worked in the intensive care units of Anesthesiology [Disciplina de Anestesiologia, Dor e Terapia Intensiva] (ANEST); Pulmonology (PULMO) and Emergency Department (ED) of Hospital São Paulo from September to December 2008. These units have fixed clinical teams, in addition to several specialties residents rotating in monthly training periods. In this study, only the fixed physicians and intensive care, internal medicine and pulmonology residents in apprenticeship in ANEST, ED and PULMO, respectively, were included. Anesthesiology residents were excluded from ANEST analysis in order to prevent a selection bias, as these doctors have a different background on this subject.
The study was conducted by means of a questionnaire completion. Considering the need to maintain the subjects' confidentiality, and that the signature of an informed consent form would render the study conduction unfeasible, we opted to inform the subjects, in the questionnaire heading, that completing it would mean consenting to participate in the study.
The questionnaire, in addition to the subject's demographics and medical activity information, had questions to evaluate the physicians' routine during intubation and their knowledge on the subject. For the sake of validation, the questionnaire was completed by a difficult airways expert anesthesiologist. Later, five specialists certified by the Associação de Medicina Intensiva Brasileira [Brazilian Intensive Medicine Association] completed the validation, marking all correct answers within 30 minutes.
The physicians who agreed to participate completed the questionnaire during their work shift. After completion, the questionnaire was inserted in an envelope and sealed. In addition, it was verified with each ICU head the existence of a proper airways management protocol, including practices for difficult airway.
The results are presented descriptively, with percents for each alternative response. The erased responses were cancelled. Regarding the differences between rapid sequence and classical intubation, each correct response was attributed one point, and the total points was named grade.
Comparisons were conducted between the different units regarding the percentages and mean grade, as well as the physicians' characteristics. The categorical variables were analyzed with the Pearson's Chi-square test. The continuous variables, after submitted to the Shapiro-Wilk normality test, were expressed as mean plus/minus standard deviation, and compared using the t Student test. Regarding the categorical variables, when a significant difference was found, the bipartite Chi square test was conducted, to indicate the units which effectively differed from each other. The Epi Info™ 3.4.1 statistical package was used, and p < 0.05 values were considered statistically significant.
In the ANEST group, 46 out of 48 physicians were included (95.83%); from these, 12 were residents not linked to Anesthesiology (26.1%). In the ED group, 22 physicians were included (96.65% of the total doctors), being 15 residents (68.2%), and in the PULMO group 17 physicians (77.27% of the total) were included, being 16 residents (94.11%). Thus, 90.42% of the physicians working in the ICUs were included.
The ANEST physicians are significantly older than those in other ICUs (mean age: 36.6±4.6, 29.2±6.3 and 29.6±5.0 for ANEST, PULMO and ED, respectively, p=0.001). Similarly, a significant difference was observed for the time since graduation (9.5±4.5, 4.7±6.6 and 4.6±5.5 for ANEST, PULMO and ED, respectively, p=0.003), reflecting the larger residents ratio in other ICUs (26.1%, 94.1% and 68.2% for ANEST, PULMO and ED, respectively, p<0.000). Additionally, 43.5% of the ANEST physicians were certified intensive care specialists (4.9% and 9.1% for PULMO and ED, respectively, p<0.000). They have more ICU weekly working hours (41.3% of the ANEST physicians work longer than 60 hours, while 11.8% of the PULMO physicians and 15.0% of the ED ones have this workload; p=0.002); which was different for emergency department practice (ANEST 34.8%, PULMO 81.3% and ED 86.4%, p<0.000). The data on the population characteristics and multiple comparison p values are shown on table 1.
ANEST and ED have their own airway protocols, and 97.8% and 22.7%of their physicians, respectively, are aware of these. Among those aware of the protocol, it was considered easily assessable by 70.5% of the ANEST and 20% of the ED physicians. Additionally, in the ANEST group most of the professionals are aware of available devices for difficult airway in the unit (95.6%), different from the other units, which haven't these devices or whose doctors are unaware of their availability.
Some of the currently recommended OTI clinical practices were mentioned by most of the ICUs physicians, as the hypnotic and opioid association use (97.6%) and pre-oxygenation (91.8%). Midazolam was the preferred hypnotic (61.2%), however etomidate had its use more mentioned by ANEST physicians (40%, 5.9% and 27.3% for ANEST, PULMO and ED, respectively, p=0.01). The initial use of opioids followed by hypnotic and then NMB was the order mentioned by 75% of the ANEST physicians versus 35.3% for PULMO and 68.2% for ED. Non-use of other drugs such as lidocaine, beta-blocker, ,metoclopramide and ranitidine was mentioned by 73% of the professionals.
The sub-occipital pad was used for 44.6% of the OTIs, with no ICUs differences (p=0.1). Some difficult airway protocol practices, however, are more largely used by the ANEST physicians, such as considering all ICU patients as full stomach (34.8%, 11.8% and 9.5% for ANEST, PULMO and ED, respectively, p=0.002) and use of NMB for OTIs (65.2%, 17.6% and 27.3% for ANEST, PULMO and ED, respectively, p<0.000).
Although most of the physicians reported to know the differences between the rapid sequence and classical intubation (93.3%, 70.6% and 90.9% for ANEST, PULMO and ED, respectively, p=0.042), they weren't able to correctly indicate these differences (mean 2.28±0.92, 2.08±0.90 and 2.10±0.85 for ANEST, PULMO and ED, respectively, p=0.6). Non use of assisted ventilation before the first attempt in the rapid sequence was reported as a difference by only 20.3% of the physicians. Shortening the inter-drugs interval was marked as a difference by 51.3% of the doctors; 57.1% of them indicated a mandatory Sellick maneuver as being a difference between the rapid sequence and classical intubation. Fast acting NMB use was also marked by most of the physicians (83.8%) as a difference between the intubation modes, and this could explain why succinylcholine was the professionals' first choice (76.9%).
Almost 100% of the physicians are aware of the Sellick maneuver, however only 15.4% of them reported its timely use, and only 28.0% until the OTI is appropriately checked. Other data regarding the physicians' knowledge and OTI practices in the different ICUs, as well as the p values for multiple comparison analysis, can be found on tables 2 to 5.
In this study we could identify disagreement between the physicians' reported intubation techniques and the literature recommended procedures. Some unsatisfactory results were identified regarding a number of basic intubation procedures, such as fasting, sub-occipital pad use, rapid sequence and the timely use of the Sellick maneuver. Additionally, the responses to questions regarding the neuromuscular blocker chosen and the drugs administration order were shown to be different from the current recommendations.(8,24-27) These findings were more relevant in units missing their own OTI protocols or where the physicians are unaware of the existing protocols.
The results may be considered unsatisfactory even in the unit that have the most experienced intensive care physicians. The PULMO and ED results, where 50.5% of the participants are residents or non boarded-certified intensivists (41.2% of the total), could be attributable to the shorter professional experience and less qualification. However, the results in ANEST suggest that this matter is not considered priority in the intensivist formation, even in those who, theoretically, had specific airways training in some continued medical education method. These findings illustrate these education process limitations, as the retention of information was unappropriate. Comparing this study findings with the literature,(13-20) it can be noticed that this study was broader, analyzing a larger number of variables. Regarding initial OTI practices, pre-oxygenation was mentioned as usual practice by most of the physicians, as in the Morris et al.(18) and Thwaites et al.(19) studies. The use of a pad in all OTIs was overall low, however no discussions on this were found in the literature. To consider patients as having full stomach didn't reach a satisfactory rate either. In addition, the use of antiemetic, prokinetic or H2 antagonists drugs were reported only by 12.34%, different of the Thwaites et al.(19) findings, where 95% of the physicians reported using antiacids. This study, however, analyzed anesthesiology patients, where this practice relevance is well established. Despite this, even in anesthesiology, its frequency looks variable, as Morris et al.(18) documented this practice by only 4% of the respondents.
The associated use of opioid and hypnotic was reported by most of the physicians, with a preference for midazolam. In the Morris et al. study, 75% used opioid, however 51% avoided using Midazolam, being thiopental preferred by 88%, and propophol by 58%.(18) Thwaites et al. documented routine opioid use by 3%, thiopental by 96%, and etomidate by 21%.(19) These studies were developed in anesthesiology settings. Yet, in intensive therapy, Jaber et al. reported opioid use in 30%, etomidate in 50% and propophol in 14% of the OTIs.(1)
The use of NMB was relatively low, differently from other studies where most of the physicians reported its use.(16,17) In the Jaber et al. study, the use of NMB was documented in 62% of the OTIs, a rate very close to the ANEST group.(1) This may be related to the fact that this study documented OTIs performed in the ICU, and in the others only anesthesiologists were evaluated. On the other hand in the Schwartz et al.(16) study, the overall NMB use was 80%, and 22% in the Le Tacon et al.(17) study, again showing a variability of the OTI techniques used by intensivist physicians. In this study, succinylcholine was the first choice, with a higher frequency than in the Jaber et al.(1) (69%), Schwartz et al.(16) (57%), and Le Tacon et al.(17) (41%) studies. On the other hand, in the Morris et al. study this rate was 99%.(18)
The knowledge on rapid sequence intubation was unsatisfactory. However, in this context it is important to have in mind the current argument on this maneuver, not being clear if the rapid sequence should be used for all critical patients or just for specific potentially benefited groups.(6,25-26) Despite this, such a lack of knowledge could compromize its eventual benefit, as some studies have already shown high success rates with reduced complications in rapid sequence OTIs.(25,27-30)
Most of the physicians reported to use the Sellick maneuver, as in the two previous studies.(18,19) However, only a small portion of them timely perform it, differently from the observed in the Thwaites et al.(19) (78% by the induction time) and Morris et al.(18) (71% before conscious loss) studies. The actual relevance of this disputed efficacy maneuver is currently under discussion(20,31) as aspiration deaths were seen even though the maneuver use.(32,33) Schwartz and Cohen, however, argument that, of the patients who didn't aspirate during the intubation, 90% were underwent the Sellick maneuver.(34) In addition, studies in cadavers have shown the maneuver effectiveness(35) and Lawes EG et al.(36) have shown the reduced gastric insufflation during ventilation while on Sellick maneuver. No maneuver effectiveness was shown in prospective studies due to possible ethical issues involved. Thus, as previously said, the health care professionals training on correct maneuver use appears to be appropriate, in order to prevent mistakes and complications.
This study have some strengths. Although being a single center study that can't be considered representative of the actual medical knowledge, the majority of three different ICUs physicians were evaluated. Additionally, this was a broad and validated questionnaire, used in a fashion that protected the participants' confidentiality. The questions should be answered in the presented sequence, not being allowed to go back to previous questions. This was particularly relevant for the question regarding knowledge on rapid sequence intubation.
On the other hand, there were limitations. A questionnaire is not necessarily a good way to evaluate knowledge, although it was long, having varied and validated questions. Additionally, due to the proximity of the ANEST with the Anesthesiology, perhaps the findings were better than what would be found in other ICUs with similar proportion of intensive medicine physicians. The fact of being an University hospital may also have overestimated the real national physicians' knowledge.
The physicians' knowledge on intensive therapy OTI is unsatisfactory, even among the most qualified professionals. It is necessary to evaluate if there is an agreement between the responses to the questionnaire and the actual clinical practice. It would be then possible to prevent iatrogenias and complications entailed by poor compliance to the good practices.
We would like to thank doctors Úrsula Guirro and Claudia Lutke for their support on preparation of the questionnaire used in this study.
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Publication in this collection
26 July 2010
Date of issue
14 Apr 2010
23 Feb 2010