ORIGINAL CONTRIBUTION cricothyrotomy, prehospital
Can Nurses Perform Surgical Cricothyrotomy With Acceptable Success and Complication Rates? Study objective: This study was undertaken to determine whether flight nurses can perform surgical cricothyrotomies with acceptable success and complication rates. Methods: This case series examined the survival, success, and complication rates of surgical cricothyrotomy. A specially trained flight nurse retrospectively reviewed all prehospital, emergency department, inpatient, autopsy; and outpatient follow-up records. Results: Fifty-five consecutive patients in whom surgical cricothyrotom y was attempted by a flight nurse during a two-and-one-half-year period were studied. Patients ranged in age from 9 to 76 years. The airway was not cannulated successfully by a flight nurse in two patients. In two patients, the tube was not in the cricothyroid space (one in the upper tracheal rings, and the other in the larynx). In three patients, packing was insufficient to stop bleeding from around the operative site; and in three the tube became occluded by blood in the emergency department. Finally, two patients developed subglottic stenosis. Conclusion: Surgical cricothyrotomy in the field can be performed reliably by specially trained nurses. Because only the most critically ill or injured patients with unmanageable airways are subjected to this procedure, a significant complication rate can be anticipated. [Nugent WL, Rhee KJ, Wisner DH: Can nurses perform cricothyrotomy with acceptable success and complication rates? Ann Emerg Med April 1991;20:367-370.] INTRODUCTION Establishing a definitive airway in patients in the field is of vital importance to patient outcome. ~-3 Special difficulties arise when oral or nasal intubation is impossible or contraindicated. Recent reports suggest that surgical cricothyrotomy may be useful in this situation.4, s The purpose of this study was to examine the survival, success, and complication rates experienced by patients in whom surgical cricothyrotomy was performed by specially trained nurses.
Wendy L Nugent, RN* Kenneth J Rhee, MDt David H Wisher, MD:~ Sacramento, California From the Department of Nursing Administration;* Division of Emergency Medicine, Department of Internal Medicine;t and the Department of Surgery,t University of California, Davis Medical Center, Sacramento. Received for publication May 3, 1990. Revision received September 10, 1990. Accepted for publication October 1, 1990. Partial funding for this research was provided by a grant from Aerospatiale Helicopter Corporation. Address for reprints: Kenneth J Rhee, MD, Division of Emergency Medicine/Trailer 1219, University of California, Davis Medical Center, 2315 Stockton Boulevard, Sacramento, California 95817.
MATERIALS A N D M E T H O D S This retrospective study examined all patients in w h o m a cricothyrotomy was attempted by Life Flight, the University of California, Davis helicopter service, between May 1987 and November 1989. Patients who were discharged from the hospital were considered survivors. Success was defined as placement of an appropriate tube into the trachea. The immediate complications specifically sought were 1) bleeding from around the operative site that was uncontrolled by the application of direct pressure and required surgical intervention, 2) tube malfunction (ie, any event in the emergency department or operating room that required replacement of the tube), 3) incorrect site of tube placement (ie, in the airway but not in the cricothyroid space), and 4) laryngeal fracture. The late complications specifically sought were subglottic stenosis (by autopsy or endoscopic report) and dysphonia (a significant voice change documented in the medical record or by patient complaint during the telephone follow-up interview). Complication rates were calculated in two ways: all immediate complications divided by all patients in w h o m a tube was successfully placed, or immediate and late complications divided by all pa-
60/367
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SURGGAL CRICOTHYROTOMY Nugent, Rhee & Wisher
dents not undergoing CPR in whom a tube was placed successfully. The flight nurses received special didactic instruction and animal laboratory training (a total of approximately six hours) before they were certified to perform surgical cricothyr0tomy. T h e y w o r k e d u n d e r the guidance of an algorithm that directed airway m a n e u v e r s (oro tracheal, nasotracheal, or surgical cricothyrotomy) on a p p r o p r i a t e patients. The algorithm defined a minimum level of airway m a n a g e m e n t that was expected and was based on anatomical injury, respiratory effort, and Glasgow Coma Score. 6 The flight nurse was always allowed the option of being more aggressive (attempting endotracheal intubation or cricothyrotomy), even if it was not prescribed in the algorithm. The procedure of surgical cricothyrotomy called for stabilization of the thyroid cartilage, a horizontal skin incision over the cricothyroid membrane with a s u b s e q u e n t incision through the membrane, introduction of either a f i n g e r or a t r a c h e a l spreader, and, finally, introduction of the tube. In the first six patients, a 6.5 endotracheal tube was used, but all subsequent patients were intubated with a low pressure cuffed tracheostomy tube (no. 6 Shiley). A flight nurse reviewed all records pertaining to prehospital, ED, inpatient, and outpatient follow-up care. In addition, autopsies were reviewed if the patient died; when possible, patients who survived were contacted by telephone.
RESULTS During the study period, 1,863 patients w e r e t r a n s p o r t e d by Life Flight. Of these, 16.2% (302) had airway m a n e u v e r s performed. There were 56 patients on w h o m surgical cricothyrotomy was attempted by a flight nurse. One of these patients was excluded from the study because he was transported to another hospital and the record was unavailable. Of the 55 patients in the study group, 43 were male and 12 were female. The age range was 9 to 76 years. All but one cricothyrotomy occurred in the field; one was performed in the transferring hospital's ED. Almost all of the patients were victims of either blunt or penetrating trauma (Table 1). During the study period, however, there was a change 20:4 April 1991
TABLE 1. Diagnostic groups No. of Patients (%)
Group
Respiratory arrest in a medical patient 1 (1.8) Burns 1 (1,8) Penetrating trauma 3 (5.5) Penetrating trauma and cardiac arrest 3 (5.5) Blunt trauma 28 (50.9) Blunt trauma and cardiac arrest 14 (25.5) Blunt and penetrating trauma 1 (1.8) Nontrauma and cardiac arrest 2 (3.6) Near-drowning 2 (3.6) Total 55 (100)
TABLE 2. Patients undergoing CPR by year Year
No. of Patieuls Undergoing CPR (%)
1987 1988 1989
6/10 (60) 8/22 (34.4) 5/23 (21.7)
in the type of patient on whom the procedure was performed. In the first year of the study, most patients were unlikely to survive (undergoing CPR on arrival of the flight crew), whereas in the second and third years, those undergoing CPR constituted a minority of the patients (Table 2). In 39 patients (70.9%), cricothyrotomy was performed because other techniques failed. In 16 patients, cricothyrotomy was the initial procedure performed by the flight nurse (Table 3). There were two patients in whom the trachea could not be cannulated successfully by a flight nurse (two of 55, or 3.6%) Both were female. In the first patient, the trachea had been avulsed from the thyroid cartilage, and the proximal end of the trachea could not be located. In the second, the airway was located, but the no. 6 t r a c h e o s t o m y t u b e could not be passed. T h e p r o c e d u r e was completed successfully by a physician after the helicopter landed. Fifteen patients survived to hospital discharge (Table 4). Of these 15, two were discharged in a chronic vegetative state and subsequently died. Ten p a t i e n t s h a d c o m p l i c a t i o n s ; eight immediate and two late (Figure). The i m m e d i a t e complication rate for all patients was 15.1% (eight Annals of Emergency Medicine
TABLE 3. Indication for cHcothyrotomy No Prior Life Flight Airway Intervention Massive hemorrhageand vomit Midface smash Esophageal intubation on Life Flight arrival Failed Nasal Intuhations Unable to perform and clenched Massive hemorrhageand vomit Became apneic during attempt and clenched Failed Oral Intubations Midface smash, massive hemorrhage, and vomit obscuring cord visualization Failed Oral and Nasal Intubation Massive hemorrhageand vomit Miscellaneous Unable to confirm tube placement Physician at other facility started, and Lile Flight completed Needle cricothyrotomy in place on Life Flight arrival and clenched Respiratory arrest in flight Laryngeal fracture Laryngospasms No other equipment available
No. o! Patients (%) 3 (5.5) 5 (9.1) 1 (1.8) 14 (25.5) 5 (9.1) 2 (3.6)
14 (25,5) 4 (7.3) 1 (1.8) 1 (1.8) 1 (1.8) 1 (1.8) 1 (1,8) 1 (1.8) 1 (1.8)
TABLE 4. Patient outcomes Outcome Died in ED Died in operating room or postanesthetic recovery room Died in inpatient units Discharged
No. of Patients (%) 21 (38) 7 (13) 12 (22) 15 (27)*
*Length ol stay lor survivors: Five to 54 days (average, 24 days).
of 53). If all complications (immediate and late) and only patients not undergoing CPR are considered, then the complication rate was 28.6% (ten
of 35). DISCUSSION Results from this study suggest that properly trained nurses can perform surgical cricothyrotomy in the field with a high success rate (96.4%) but a significant complication rate. Three patients in this series had their tube replaced because the lumen became occluded by blood. This problem has not been reported in 368/61
SURGICAL CRICOTHYROTOMY Nugent, R h e e & W i s n e r
TABLE 5. Emergency cricothyrotomy studies Reference
Location
Personnel
McGill et al 7 Erlandson et al8 Boyd and Conlan 9 Miklus et al4 Spaite and Joseph s Present study
Hospital Hospital Hospital Field Field Field
Physicians Physicians Physicians Physicians Paramedics Nurses
Survivors (%) 12/38 5/39 17/19 7/20 2/16 15/54
(31.6) (12.8) (89.5) (35:0) (12.5) (27.7)
Success Rate (%) 35/38 39/39 19/19 20/20 14/16 53/55
(92.1) (100) (100) (100) (87.5) (96.4)
ComplicationRate (%)* 7/35 7/39 2/19 0/20 2/14 8/53
(20.0) (17.9) (10.5) (0.0) (14.3) (15.1)
*Denominalor includes only patients in whom a tube was placed successfully in the airway Numerator includes lhe following complications: hemorrhage, occlusion of the tube, laryngeal fracture, or placement in lhe airway but nol in the cricothyroid space (excludes failed attempts, procedure times, and late complications).
Clinical
Complications
50-year-old man with knife wound to larynx; discharged alive; Glasgow Coma Score (GCS) at ED = 3; knife wound extended the larynx
Extensive bleeding from neck; impossible to exclude bleeding from incision Endotracheal tube became occluded by blood and required replacement in surgery; dysphonia eventually developed Endotracheal tube became occluded by blood and required replacement in ED Subglottic stenosis and dysphonia developed
18-year-old man with massive head trauma; died in ED; GCS at ED 3 22-year-old woman with blunt head trauma and neck impaled by a stick; prolonged oral intubation eventually leading to a tracheostomy; discharged alive; GCS at ED = 3 9-year-old girl; blunt trauma CPR; died in ED 30-year-old man with head trauma; discharged alive; three nasotracheal attempts in the field; GCS at ED = 8 40-year-old man with head trauma; chronic vegetative state; GCS at ED = 3 17-year-old boy with blunt trauma; died after three days in ICU; initial incision made by a physician in another hospital; procedure completed by flight nurse; GCS at ED - 3 35-year-old man with head injury; discharged alive; GCS at ED - 4 17-year-old girl with blunt trauma; discharged alive; GCS at ED = 8
16-year-old girl with head injury; discharged alive; orally intubated on arrival and eventually had tracheostomy; GCS at ED - 5
Airway not cannulated; complete tracheolaryngeal disjunction Shiley tracheostomy tube became occluded by blood in surgery and required replacement Placement through right side of laryngeal cartilage Postprocedure bleeding that required surgical revision to stop hemorrhage
Placement through upper tracheal rings; bleeding that required surgical revision Cricothyroid space incised but Shiley tracheostomy tube could not be placed by nurse; completed by physician after arrival Subglottic stenosis
FIGURE. Patients w i t h complications. severity of patient condition has varied tremendously. It is obvious that a series with a high immediate mortality rate may have a lower complication rate because certain complications cannot be expressed (eg, hemorrhage, dysphonia, subglottic stenosis). To most clearly present the data from this study, the complication rate was calculated twice; the first calculation included all patients in the denominator. (This is similar to t h e m e t h o d s u s e d in p r e v i o u s studies; therefore, this complication rate was used when comparing these data with results of other research.) The second calculation included only patients who could have had complications (ie, some signs of life on arrival of the flight crew). Complication rates for all studies were calculated using as the denominator only patients in whom an app r o p r i a t e tube was s u c c e s s f u l l y placed in the airway. Only immediate complications (eg, hemorrhage, tube occlusion, laryngeal fracture, or placement in the airway but not in the cricothyroid space) were used to calculate the numerator. Procedure times and late complications were not used to calculate complication rates.
o t h e r series.4,5, 7-9 W h e t h e r these complications occurred because of the procedure, because of excessive bleeding from the face and upper airway, because a n endotracheal tube rather than a tracheostomy tube was used (in two cases), or because of ina t t e n t i o n to p o s t c r i c o t h y r o t o m y nursing (eg, suctioning) cannot be determined. However, the fact that packing was insufficient to stop the 62/369
hemorrhage in three additional patients suggests that hemostatis was not optimal. C o m p a r i s o n of the success and complication rates in this series to those reported previously is difficult. All studies, including this one, have been retrospective and uncontrolled and have used slightly different definitions to calculate c o m p l i c a t i o n rates (Table 5).¢5,7-9 Furthermore, the Annals of Emergency Medicine
The rate of successful cannulation of the airway appears to be high. Paramedics without special training (other than the training required for certification) achieved an 87.5% success rate. 5 Physicians with limited experience (surgical and emergency medicine residents in their second year of postgraduate training without 2 4 - h o u r a t t e n d i n g staff support) achieved a 92.1% success rate. 7 Specially trained flight nurses in this se20:4 April 1991
SURGICAL CRICOTHYROTOMY Nugent, Rhee &Wisner
ries achieved a 96.4% success rate, including one patient with an injury that probably precluded any kind of tracheal intubation (complete tracheolaryngeal disjunction). Physicians with more experience have had even higher success rates.4,8, 9 The complication rate for surgical cricothyrotomy appears to be significant; only one series had a complication rate of less than 10%. In that program, cricothyrotomy was conducted by physicians in their third postgraduate year or later. 4 In the two series with 100% success rates but significant complication rates, the personnel were "junior staff ''9 or residents in their second postgraduate year of training. 8 When calculated in a similar way, the complication rate in the present study is similar to those of these earlier reportsl The data from this series suggest, however, that the actual complication rate (early and late complica-
20:4 April 1991
tions using as the denominator only patients who might display complications) is much higher. This significant complication rate should not be unexpected. Only critically ill patients with severely compromised airways in whom other maneuvers had failed or were impossi: ble had s u r g i c a l c r i c o t h y r o t o m y performed. The extremis of the patients also explains why cricothyrotomy must still be used in some situations. The a l t e r n a t i v e - airway compromise with little or no ventilation - is unacceptable.
able given the potentially lifesaving nature of surgical cricothyrotomy.
CONCLUSION Surgical c r i c o t h y r o t o m y in the field Can be performed reliably by specially trained nurses. Because only the most critically ill or injured patients with unmanageable airways are subjected to this procedure, a significant complication rate can be anticipated. We believe this is accept-
6. Rhee K, O'Malley R: The effect of an airway algorithm on flight nurse behavior. J Air Med Transport 1990;9:6-8.
Annals of Emergency Medicine
REFERENCES 1. Subcommittee on Advanced Trauma Life Support: Advanced Trauma Life Support Program Instructor Manual. Chicago, American College of Surgeons, 1989. 2. Baxt W, Moody P: The impact of a physician as a part of the aeromedical prehospitaI team in patients with blunt trauma. JAMA 1987;Z57:3246-3250. 3. Pepe P, Copass M, Joyce T: Prehospital endotracheaI intubation: Rationale for training emergency medical personnel. Ann Emerg Med 1985~14:1085. 4. Miklus R, Elliott C, Snow N: Surgical cricothyrotomy in the field: Experience of a helicopter transport team. ] Trauma 1989;29:506-508. 5. Spaite D, Joseph M: Prehospital cricothyrotomy: An investigation of indications, technique, complications, and patient outcome. Ann Emerg Med 1990;19:279-285.
7. McGill J, Clinton J, Ruiz E: Cricothyrotomy in the e m e r g e n c y d e p a r t m e n t . A n n Emerg M e d 1982;11: 361-364. 8. Erlandson M, Clinton J, Rniz E, et al: Cricothyroto my in the emergency department revisited, f Emerg Med 1989;7:115-118. 9. Boyd A, Conlan A: Emergency cricothyrotomy: Is its use justified? Surg Rounds 1979;2:19-23.
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Can Nurses Perform Surgical Cricothyrotomy With Acceptable Success and Complication Rates? Study objective: This study was undertaken to determine whether flight nurses can perform surgical cricothyrotomies with acceptable success and complication rates. Methods: This case series examined the survival, success, and complication rates of surgical cricothyrotomy. A specially trained flight nurse retrospectively reviewed all prehospital, emergency department, inpatient, autopsy; and outpatient follow-up records. Results: Fifty-five consecutive patients in whom surgical cricothyrotom y was attempted by a flight nurse during a two-and-one-half-year period were studied. Patients ranged in age from 9 to 76 years. The airway was not cannulated successfully by a flight nurse in two patients. In two patients, the tube was not in the cricothyroid space (one in the upper tracheal rings, and the other in the larynx). In three patients, packing was insufficient to stop bleeding from around the operative site; and in three the tube became occluded by blood in the emergency department. Finally, two patients developed subglottic stenosis. Conclusion: Surgical cricothyrotomy in the field can be performed reliably by specially trained nurses. Because only the most critically ill or injured patients with unmanageable airways are subjected to this procedure, a significant complication rate can be anticipated. [Nugent WL, Rhee KJ, Wisner DH: Can nurses perform cricothyrotomy with acceptable success and complication rates? Ann Emerg Med April 1991;20:367-370.] INTRODUCTION Establishing a definitive airway in patients in the field is of vital importance to patient outcome. ~-3 Special difficulties arise when oral or nasal intubation is impossible or contraindicated. Recent reports suggest that surgical cricothyrotomy may be useful in this situation.4, s The purpose of this study was to examine the survival, success, and complication rates experienced by patients in whom surgical cricothyrotomy was performed by specially trained nurses.
Wendy L Nugent, RN* Kenneth J Rhee, MDt David H Wisher, MD:~ Sacramento, California From the Department of Nursing Administration;* Division of Emergency Medicine, Department of Internal Medicine;t and the Department of Surgery,t University of California, Davis Medical Center, Sacramento. Received for publication May 3, 1990. Revision received September 10, 1990. Accepted for publication October 1, 1990. Partial funding for this research was provided by a grant from Aerospatiale Helicopter Corporation. Address for reprints: Kenneth J Rhee, MD, Division of Emergency Medicine/Trailer 1219, University of California, Davis Medical Center, 2315 Stockton Boulevard, Sacramento, California 95817.
MATERIALS A N D M E T H O D S This retrospective study examined all patients in w h o m a cricothyrotomy was attempted by Life Flight, the University of California, Davis helicopter service, between May 1987 and November 1989. Patients who were discharged from the hospital were considered survivors. Success was defined as placement of an appropriate tube into the trachea. The immediate complications specifically sought were 1) bleeding from around the operative site that was uncontrolled by the application of direct pressure and required surgical intervention, 2) tube malfunction (ie, any event in the emergency department or operating room that required replacement of the tube), 3) incorrect site of tube placement (ie, in the airway but not in the cricothyroid space), and 4) laryngeal fracture. The late complications specifically sought were subglottic stenosis (by autopsy or endoscopic report) and dysphonia (a significant voice change documented in the medical record or by patient complaint during the telephone follow-up interview). Complication rates were calculated in two ways: all immediate complications divided by all patients in w h o m a tube was successfully placed, or immediate and late complications divided by all pa-
60/367
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SURGGAL CRICOTHYROTOMY Nugent, Rhee & Wisher
dents not undergoing CPR in whom a tube was placed successfully. The flight nurses received special didactic instruction and animal laboratory training (a total of approximately six hours) before they were certified to perform surgical cricothyr0tomy. T h e y w o r k e d u n d e r the guidance of an algorithm that directed airway m a n e u v e r s (oro tracheal, nasotracheal, or surgical cricothyrotomy) on a p p r o p r i a t e patients. The algorithm defined a minimum level of airway m a n a g e m e n t that was expected and was based on anatomical injury, respiratory effort, and Glasgow Coma Score. 6 The flight nurse was always allowed the option of being more aggressive (attempting endotracheal intubation or cricothyrotomy), even if it was not prescribed in the algorithm. The procedure of surgical cricothyrotomy called for stabilization of the thyroid cartilage, a horizontal skin incision over the cricothyroid membrane with a s u b s e q u e n t incision through the membrane, introduction of either a f i n g e r or a t r a c h e a l spreader, and, finally, introduction of the tube. In the first six patients, a 6.5 endotracheal tube was used, but all subsequent patients were intubated with a low pressure cuffed tracheostomy tube (no. 6 Shiley). A flight nurse reviewed all records pertaining to prehospital, ED, inpatient, and outpatient follow-up care. In addition, autopsies were reviewed if the patient died; when possible, patients who survived were contacted by telephone.
RESULTS During the study period, 1,863 patients w e r e t r a n s p o r t e d by Life Flight. Of these, 16.2% (302) had airway m a n e u v e r s performed. There were 56 patients on w h o m surgical cricothyrotomy was attempted by a flight nurse. One of these patients was excluded from the study because he was transported to another hospital and the record was unavailable. Of the 55 patients in the study group, 43 were male and 12 were female. The age range was 9 to 76 years. All but one cricothyrotomy occurred in the field; one was performed in the transferring hospital's ED. Almost all of the patients were victims of either blunt or penetrating trauma (Table 1). During the study period, however, there was a change 20:4 April 1991
TABLE 1. Diagnostic groups No. of Patients (%)
Group
Respiratory arrest in a medical patient 1 (1.8) Burns 1 (1,8) Penetrating trauma 3 (5.5) Penetrating trauma and cardiac arrest 3 (5.5) Blunt trauma 28 (50.9) Blunt trauma and cardiac arrest 14 (25.5) Blunt and penetrating trauma 1 (1.8) Nontrauma and cardiac arrest 2 (3.6) Near-drowning 2 (3.6) Total 55 (100)
TABLE 2. Patients undergoing CPR by year Year
No. of Patieuls Undergoing CPR (%)
1987 1988 1989
6/10 (60) 8/22 (34.4) 5/23 (21.7)
in the type of patient on whom the procedure was performed. In the first year of the study, most patients were unlikely to survive (undergoing CPR on arrival of the flight crew), whereas in the second and third years, those undergoing CPR constituted a minority of the patients (Table 2). In 39 patients (70.9%), cricothyrotomy was performed because other techniques failed. In 16 patients, cricothyrotomy was the initial procedure performed by the flight nurse (Table 3). There were two patients in whom the trachea could not be cannulated successfully by a flight nurse (two of 55, or 3.6%) Both were female. In the first patient, the trachea had been avulsed from the thyroid cartilage, and the proximal end of the trachea could not be located. In the second, the airway was located, but the no. 6 t r a c h e o s t o m y t u b e could not be passed. T h e p r o c e d u r e was completed successfully by a physician after the helicopter landed. Fifteen patients survived to hospital discharge (Table 4). Of these 15, two were discharged in a chronic vegetative state and subsequently died. Ten p a t i e n t s h a d c o m p l i c a t i o n s ; eight immediate and two late (Figure). The i m m e d i a t e complication rate for all patients was 15.1% (eight Annals of Emergency Medicine
TABLE 3. Indication for cHcothyrotomy No Prior Life Flight Airway Intervention Massive hemorrhageand vomit Midface smash Esophageal intubation on Life Flight arrival Failed Nasal Intuhations Unable to perform and clenched Massive hemorrhageand vomit Became apneic during attempt and clenched Failed Oral Intubations Midface smash, massive hemorrhage, and vomit obscuring cord visualization Failed Oral and Nasal Intubation Massive hemorrhageand vomit Miscellaneous Unable to confirm tube placement Physician at other facility started, and Lile Flight completed Needle cricothyrotomy in place on Life Flight arrival and clenched Respiratory arrest in flight Laryngeal fracture Laryngospasms No other equipment available
No. o! Patients (%) 3 (5.5) 5 (9.1) 1 (1.8) 14 (25.5) 5 (9.1) 2 (3.6)
14 (25,5) 4 (7.3) 1 (1.8) 1 (1.8) 1 (1.8) 1 (1.8) 1 (1,8) 1 (1.8) 1 (1.8)
TABLE 4. Patient outcomes Outcome Died in ED Died in operating room or postanesthetic recovery room Died in inpatient units Discharged
No. of Patients (%) 21 (38) 7 (13) 12 (22) 15 (27)*
*Length ol stay lor survivors: Five to 54 days (average, 24 days).
of 53). If all complications (immediate and late) and only patients not undergoing CPR are considered, then the complication rate was 28.6% (ten
of 35). DISCUSSION Results from this study suggest that properly trained nurses can perform surgical cricothyrotomy in the field with a high success rate (96.4%) but a significant complication rate. Three patients in this series had their tube replaced because the lumen became occluded by blood. This problem has not been reported in 368/61
SURGICAL CRICOTHYROTOMY Nugent, R h e e & W i s n e r
TABLE 5. Emergency cricothyrotomy studies Reference
Location
Personnel
McGill et al 7 Erlandson et al8 Boyd and Conlan 9 Miklus et al4 Spaite and Joseph s Present study
Hospital Hospital Hospital Field Field Field
Physicians Physicians Physicians Physicians Paramedics Nurses
Survivors (%) 12/38 5/39 17/19 7/20 2/16 15/54
(31.6) (12.8) (89.5) (35:0) (12.5) (27.7)
Success Rate (%) 35/38 39/39 19/19 20/20 14/16 53/55
(92.1) (100) (100) (100) (87.5) (96.4)
ComplicationRate (%)* 7/35 7/39 2/19 0/20 2/14 8/53
(20.0) (17.9) (10.5) (0.0) (14.3) (15.1)
*Denominalor includes only patients in whom a tube was placed successfully in the airway Numerator includes lhe following complications: hemorrhage, occlusion of the tube, laryngeal fracture, or placement in lhe airway but nol in the cricothyroid space (excludes failed attempts, procedure times, and late complications).
Clinical
Complications
50-year-old man with knife wound to larynx; discharged alive; Glasgow Coma Score (GCS) at ED = 3; knife wound extended the larynx
Extensive bleeding from neck; impossible to exclude bleeding from incision Endotracheal tube became occluded by blood and required replacement in surgery; dysphonia eventually developed Endotracheal tube became occluded by blood and required replacement in ED Subglottic stenosis and dysphonia developed
18-year-old man with massive head trauma; died in ED; GCS at ED 3 22-year-old woman with blunt head trauma and neck impaled by a stick; prolonged oral intubation eventually leading to a tracheostomy; discharged alive; GCS at ED = 3 9-year-old girl; blunt trauma CPR; died in ED 30-year-old man with head trauma; discharged alive; three nasotracheal attempts in the field; GCS at ED = 8 40-year-old man with head trauma; chronic vegetative state; GCS at ED = 3 17-year-old boy with blunt trauma; died after three days in ICU; initial incision made by a physician in another hospital; procedure completed by flight nurse; GCS at ED - 3 35-year-old man with head injury; discharged alive; GCS at ED - 4 17-year-old girl with blunt trauma; discharged alive; GCS at ED = 8
16-year-old girl with head injury; discharged alive; orally intubated on arrival and eventually had tracheostomy; GCS at ED - 5
Airway not cannulated; complete tracheolaryngeal disjunction Shiley tracheostomy tube became occluded by blood in surgery and required replacement Placement through right side of laryngeal cartilage Postprocedure bleeding that required surgical revision to stop hemorrhage
Placement through upper tracheal rings; bleeding that required surgical revision Cricothyroid space incised but Shiley tracheostomy tube could not be placed by nurse; completed by physician after arrival Subglottic stenosis
FIGURE. Patients w i t h complications. severity of patient condition has varied tremendously. It is obvious that a series with a high immediate mortality rate may have a lower complication rate because certain complications cannot be expressed (eg, hemorrhage, dysphonia, subglottic stenosis). To most clearly present the data from this study, the complication rate was calculated twice; the first calculation included all patients in the denominator. (This is similar to t h e m e t h o d s u s e d in p r e v i o u s studies; therefore, this complication rate was used when comparing these data with results of other research.) The second calculation included only patients who could have had complications (ie, some signs of life on arrival of the flight crew). Complication rates for all studies were calculated using as the denominator only patients in whom an app r o p r i a t e tube was s u c c e s s f u l l y placed in the airway. Only immediate complications (eg, hemorrhage, tube occlusion, laryngeal fracture, or placement in the airway but not in the cricothyroid space) were used to calculate the numerator. Procedure times and late complications were not used to calculate complication rates.
o t h e r series.4,5, 7-9 W h e t h e r these complications occurred because of the procedure, because of excessive bleeding from the face and upper airway, because a n endotracheal tube rather than a tracheostomy tube was used (in two cases), or because of ina t t e n t i o n to p o s t c r i c o t h y r o t o m y nursing (eg, suctioning) cannot be determined. However, the fact that packing was insufficient to stop the 62/369
hemorrhage in three additional patients suggests that hemostatis was not optimal. C o m p a r i s o n of the success and complication rates in this series to those reported previously is difficult. All studies, including this one, have been retrospective and uncontrolled and have used slightly different definitions to calculate c o m p l i c a t i o n rates (Table 5).¢5,7-9 Furthermore, the Annals of Emergency Medicine
The rate of successful cannulation of the airway appears to be high. Paramedics without special training (other than the training required for certification) achieved an 87.5% success rate. 5 Physicians with limited experience (surgical and emergency medicine residents in their second year of postgraduate training without 2 4 - h o u r a t t e n d i n g staff support) achieved a 92.1% success rate. 7 Specially trained flight nurses in this se20:4 April 1991
SURGICAL CRICOTHYROTOMY Nugent, Rhee &Wisner
ries achieved a 96.4% success rate, including one patient with an injury that probably precluded any kind of tracheal intubation (complete tracheolaryngeal disjunction). Physicians with more experience have had even higher success rates.4,8, 9 The complication rate for surgical cricothyrotomy appears to be significant; only one series had a complication rate of less than 10%. In that program, cricothyrotomy was conducted by physicians in their third postgraduate year or later. 4 In the two series with 100% success rates but significant complication rates, the personnel were "junior staff ''9 or residents in their second postgraduate year of training. 8 When calculated in a similar way, the complication rate in the present study is similar to those of these earlier reportsl The data from this series suggest, however, that the actual complication rate (early and late complica-
20:4 April 1991
tions using as the denominator only patients who might display complications) is much higher. This significant complication rate should not be unexpected. Only critically ill patients with severely compromised airways in whom other maneuvers had failed or were impossi: ble had s u r g i c a l c r i c o t h y r o t o m y performed. The extremis of the patients also explains why cricothyrotomy must still be used in some situations. The a l t e r n a t i v e - airway compromise with little or no ventilation - is unacceptable.
able given the potentially lifesaving nature of surgical cricothyrotomy.
CONCLUSION Surgical c r i c o t h y r o t o m y in the field Can be performed reliably by specially trained nurses. Because only the most critically ill or injured patients with unmanageable airways are subjected to this procedure, a significant complication rate can be anticipated. We believe this is accept-
6. Rhee K, O'Malley R: The effect of an airway algorithm on flight nurse behavior. J Air Med Transport 1990;9:6-8.
Annals of Emergency Medicine
REFERENCES 1. Subcommittee on Advanced Trauma Life Support: Advanced Trauma Life Support Program Instructor Manual. Chicago, American College of Surgeons, 1989. 2. Baxt W, Moody P: The impact of a physician as a part of the aeromedical prehospitaI team in patients with blunt trauma. JAMA 1987;Z57:3246-3250. 3. Pepe P, Copass M, Joyce T: Prehospital endotracheaI intubation: Rationale for training emergency medical personnel. Ann Emerg Med 1985~14:1085. 4. Miklus R, Elliott C, Snow N: Surgical cricothyrotomy in the field: Experience of a helicopter transport team. ] Trauma 1989;29:506-508. 5. Spaite D, Joseph M: Prehospital cricothyrotomy: An investigation of indications, technique, complications, and patient outcome. Ann Emerg Med 1990;19:279-285.
7. McGill J, Clinton J, Ruiz E: Cricothyrotomy in the e m e r g e n c y d e p a r t m e n t . A n n Emerg M e d 1982;11: 361-364. 8. Erlandson M, Clinton J, Rniz E, et al: Cricothyroto my in the emergency department revisited, f Emerg Med 1989;7:115-118. 9. Boyd A, Conlan A: Emergency cricothyrotomy: Is its use justified? Surg Rounds 1979;2:19-23.
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