Case 112 The Glidescope is a video laryngoscope with a TV camera built into the blade. The views obtained can be quite striking, as with the case shown below. Microminiature TV camera and dual LED light source integrated into the laryngoscope blade
Description: This technique utilizes a wire passed retrograde from a puncture in the cricothyroid membrane to the mouth to allow passage of an endotracheal tube into the trachea. Advantages: Placement of the wire through the cricothyroid membrane should ensure passage of the endotracheal tube into the trachea. Does not require visualization of the larynx. May be performed rapidly by skilled practitioner. Disadvantages: May cause bleeding in the airway. The endotracheal tube may not pass easily into the larynx, even when the wire is correctly passed. This may occur when the endotracheal tube engages the epiglottis or the glottic cartilaginous structures. It may also occur if the wire kinks or bends during attempted passage of the endotracheal tube. http://www.gasnet.org/airway/opt10.htm
Sanchez, Tony F. Retrograde intubation. Anesthesiology Clinics of North America 1995 Jun; 13(2):439-450. Waters DJ. Guided blind endotracheal intubation for patients with deformities of the upper airway." Anaesthesia 1963;18:158-62 (Original description from Nigeria).
Synopsis of Retrograde Intubation www.metrohealthanesthesia.com/edu/airway/retrograde.htm www.biodigital.org/voz2/W3M.htm
Retrograde Nasal Intubation In A Case Of Subdural Hematoma With Mandible Fracture: A Case Report The Internet Journal of Anesthesiology. 2006 Volume 10 Number 2
The Parker Flex-Tip TM tubes are available in sizes 6.5, 7.0, 7.5, and 8.0mm ID. The tapered, centered, flexible tip of the Parker Flex-Tip TM Endotracheal Tube is designed for: Better tip visibility Gentle sliding off of delicate anatomical structures in the airway Easier insertion through narrow glottic openings Snag-free "railroading" along fiberoptic scopes Gentle "skiing" down tracheal walls
28 yr old male, motorcycle collision, fall over pieces of wood. The patient was haemodynamically normal, conscious, just demanding the removal of the stick. Nevertheless, he was submitted to an emergent left thoracotomy, and left laparotomy. The piece of wood was just located behind the sternum and in front of the heart with no major vascular or cardiac injury found, only a perforation of the diaphragm. Intraabdominally, the piece passed between the left lobe of the liver and the spleen with no further injury. We found this almost unbelievable! Luis Filipe Pinheiro, Viseu, Portugal Trauma Image Bank Case 4
Refuses Awake Intubation A snarly and demanding 80 year old lady issues an endless stream of demands to her care givers. She is accustomed to getting what she wants, coming from a large family which she was the matriarch. Case 10
Refuses Awake Intubation She presented with recurrent bowel obstructions following a messy appendectomy complicated by peritonitis. On most occasions an N/G tube would do the trick, but twice a laparotomy became necessary.
Refuses Awake Intubation The first time in, she was difficult to intubate because her larynx was just too anterior- despite a “BURP” maneuver seemed to push things into position. However, in the end a colleague got the tube in using a Gum Elastic Bougie he kept nearby for just this situation.
Refuses Awake Intubation The next time around the anesthesia team decided on awake fiberoptic intubation, but it required quite a bit of coaxing, and the experience was a terrible one for the patient, remembering that awful choking feeling whenever the scope was introduced.
Refuses Awake Intubation The old chart put the picture differently: “Awake FOB intubation L nostril with 2% lidocaine gel, midazolam 1 mg IV and glycopyrrolate 0.2 mg IV. Difficult procedure because of excessive secretions with some bleeding, as well as frequent swallowing and gagging”.
Refuses Awake Intubation Now it is your turn to give the anesthetic to allow the surgeons to unwrap her bowels once again. You explain about the awake intubation business, but she’s not biting. She views the whole process as barbaric and she simply will not allow herself to be subjected to awake intubation.
Refuses Awake Intubation Just as firmly, she refuses to have any kind of needle put into her back! What should you do after you give up trying to coax her?
Refuses Awake Intubation Discussion Options to consider include: 1. Stun her with just a little ketamine (or other agent) and get on with the job of an “awake” intubation, holding her down if necessary. 2. Get a psychiatrist to declare her incompetent. If s/he agrees, go to 1. If s/he disagrees, go to 3, 4 or 5.
Refuses Awake Intubation Discussion 3. Try your usual rapid sequence induction and if you can’t get the airway, proceed as per the ASA airway management algorithm. 4. Try your usual rapid sequence induction and if you can’t get the airway, insert an LMA, while continuing cricoid pressure throughout the case. 5. Refuse to be her anesthetist.
Fetal Distress, Emergency C/Section, Difficult Airway A 19 year old woman 38 weeks pregnant has had 4 previous operations for a complex congenital cranio-facial syndrome, all requiring fiberoptic intubation. You are now asked to provide an emergency anesthetic for a C/Section for fetal distress (profound bradycardia) for a suspected prolapsed cord. Case 11
Fetal Distress, Emergency C/Section, Difficult Airway What if a "stale" epidural (in need of a top up) were in place? What if there was no epidural in place at the time? Would you have agreed to an epidural in this lady for routine labour and delivery? What is the role of the LMA?
Fetal Distress, Emergency C/Section, Difficult Airway Your objective in this case is to get the baby out in as short a time as possible. If an epidural is already in place with a block adequate for surgery, the problem is largely solved. If the epidural had been unsatisfactory, would you consider a spinal?
Fetal Distress, Emergency C/Section, Difficult Airway If the epidural is in need of a top-up, many clinicians would choose to top up the epidural while arrangements to transfer her to the OR are being made.
Other clinicians may not be comfortable giving a lot of epidural drugs under such volatile conditions, or would worry about what to do if the block didn't end up high enough or was patchy. Fetal Distress, Emergency C/Section, Difficult Airway
If no epidural were in place the situation is more complicated: there is no "right answer". Clinicians with a lot of experience with spinals for c/sections point out how quickly a spinal can be done, but is not a great option if your experience with spinals for C/Sections is limited. Fetal Distress, Emergency C/Section, Difficult Airway
Other options local anesthesia (prepare two 50 ml syringes of 0.5% lidocaine with epi (= 5 mg/ml) and give up to 7 mg/kg [= 500 mg (100 ml) in a 70 kg parturient] quick awake FO intubation quick blind nasal intubation None of those options is especially satisfactory ! Fetal Distress, Emergency C/Section, Difficult Airway
High Dose Fentanyl and Pancuronium Induction An otherwise healthy 67 year old man with unstable angina underwent an uneventful induction with fentanyl 5000 g and pancuronium 10 mg for a planned 3-vessel CABG. Case 12
High Dose Fentanyl and Pancuronium Induction At laryngoscopy the view is terrible - only the epiglottis is visible. (Grade III) Three attempts at intubation are unsuccessful, despite use of a stylet, “BURP” and careful head positioning - the larynx is just too anterior. The ETT ends up in the esophagus with each attempt. What now?
High Dose Fentanyl and Pancuronium Induction The use of high-doses of a narcotic with high doses of long-acting muscle relaxant remains a common anesthetic technique for cardiac surgery. The technique is valued because of its hemodynamic stability.
The key disadvantage of this technique is that neither the narcotic component nor the relaxant component of the anesthetic is readily reversible. High Dose Fentanyl and Pancuronium Induction
“Waking” the patient using naloxone and neostigmine is not a particularly viable option (although I have heard of it being done after a long period of ventilation by face mask). High Dose Fentanyl and Pancuronium Induction
Probably the best thing to do is to maintain positive pressure ventilation by mask, while calling for a fiberoptic bronchoscope and another pair of skilled hands. Use of a mask designed for bronchoscopy (Patil-Syracuse mask) allows BVM ventilation to continue.
The intubating laryngeal mask airway (ILMA) is also potentially useful in this setting. In many cases it is easier to ventilate a patient with an LMA than with a face mask. High Dose Fentanyl and Pancuronium Induction
Laryngospasm Under Mask Anesthesia A 22 year old woman undergoes a fentanyl/nitrous oxide/sevoflurane anesthetic for a D&C. She is breathing well until the dilator is introduced - then she develops laryngospasm that won't break with sustained airway pressure. The pulse oximeter reading has dropped to 92% from 98%.
Laryngospasm Under Mask Anesthesia What would you do now? How would you treat persistent laryngospasm in a patient believed to be MH susceptible?
Definition Laryngospasm is closing of the larynx via contracture of the intrinsic muscles of the larnyx. It commonly occurs in anesthesia when the larnyx is stimulated by secretions or airway instrumentation, especially in combination with light anesthesia.
Laryngospasm Notch The laryngospasm notch is located just behind the earlobe. It is bordered by the base of the skull superiorly, the mastoid process posteriorly, and the ramus of the mandible anteriorly. Stimulation of laryngospasm notch can break a laryngospasm and also assist the anesthetist in initiating spontaneous respirations in the sedated patient. When performed properly, the index or middle fingers should be placed in the notch with pressure applied in a medial and cephalad direction. This opens the airway by sliding the mandible forward and produces an extremely painful stimulus, usually resulting in a deep breath. [From Wikipedia] See also Larson. Anesthesiology. 89(5):1293-1294, November 1998.
Treatment consists of applying pressure on both sides of the head, simultaneously, on the depression located behind the ear lobes, which is limited anteriorly by the ascending ramus of the mandible adjacent to the condilus, posteriorly by the mastoid process of the temporal bone, and superiorly by the base of the skull, while at the same time dislocating the mandible anteriorly. An essential component of the treatment is the severe pain that the patient experiences because of the firm pressure that is applied to the ramus of the mandible, the facial nerve, and perhaps the deep lobe of the parotid gland. [Larson]
Laryngospasm Under Mask Anesthesia There are several ways to break laryngospasm, but succinylcholine (in my experience) is the most effective agent (usually 10 mg will do the trick)
Laryngospasm Under Mask Anesthesia Obviously, if the patient is MH susceptible, don’t attempt to break the laryngospasm with succinylcholine unless all other maneuvers fail and the patient is in extremis. Consider deepening the patient with IV propofol or using rocuronium.
Imagine that the laryngospasm in Case 13 was so bad that it lasted quite a while, so that intubation was necessary. What if following intubation, pink froth is seen to be collecting in the ETT?
“To our knowledge, this condition is previously unreported in English literature. We presume that the pathogenesis is related to alveolar and capillary damage, induced by the severe negative pressure generated by attempting to inspire against the closed upper airway.”
Post Obstructive Pulmonary Edema Postobstructive pulmonary edema is a well-recognized complication of upper airway obstruction. The mechanisms of edema formation are unclear and may be due to increased hydrostatic forces generated by high negative inspiratory pressure or (less likely) by increased permeability of the alveolar capillary membrane.
Laryngospasm has been reported to be the cause in > 50% of cases of postobstructive pulmonary edema. Other reported causes of postobstructive pulmonary edema include the following: strangulation; epiglottitis; foreign-body aspiration; hypothyroidism; inspissated tracheal secretions; hiccups; croup; thyroid goiter ; temporomandibular joint arthroscopy; difficult intubation; hematoma; upper airway tumor; oropharyngeal surgery; Ludwig angina; obesity; acromegaly; obstructive sleep apnea; mediastinal tumor; and biting the endotracheal tube or laryngeal mask.
Patients in whom postobstructive pulmonary edema develops generally have an uncomplicated hospital course followed by the rapid resolution of the pulmonary edema and short hospital stays.
Pathophysiology of the development of postobstructive pulmonary edema
58-year old female patient Recurrent head and neck cancer Limited mouth opening Very difficult to intubate using a fiberoptic bronchoscope (even ENT had considerable trouble). Stridor on extubation Patient starting to get agitated
The stridor was treated by two doses of 8 mg dexamethasone (one administered pre extubation), two doses of nebulized racemic epinephrine (0.5 ml of 2.25% epinephrine added to 2.5 ml saline), and assisted mask ventilation with the patient sitting up at 60 degrees.
On standby we had available almost every airway gadget ever manufactured, an experienced ENT surgeon, a variety of experienced anesthesiologists, and everything needed for a surgical airway.
Unfortunately, the patient did not improve and was starting to tire. Reintubation would have been even more difficult than it had been earlier. A surgical airway was starting to look like our only way out.
Treatment What saved us was a mixture of Helium (70%) and Oxygen (30%) delivered using a nonrebreathing face mask at 10 lpm. Within 5 to 10 breaths the stridor vanished and the patient’s work of breathing became manageable.
Treatment The patient was then brought to the recovery room with a large Heliox tank in tow and with full monitoring. She was then weaned off the Heliox over several hours.
Discussion Airway obstructing conditions such as epiglottitis or tracheal stenosis may be viewed as breathing through an orifice (defined as involving flow through a tube whose length is smaller than its radius).
Discussion Gas flow through an orifice is always somewhat turbulent. Under such conditions, the approximate flow across the orifice varies inversely with the square root of the gas density. This is in contrast to laminar flow conditions, where gas flow varies inversely with gas viscosity.
Discussion Note that while the viscosity values for helium and oxygen are similar, their densities are very different. GasDensity @ 20° C Air1.293 g/L Nitrogen1.250 g/L N20N201.965 g/L Helium0.178 g/L Oxygen1.429 g/L
Take Home Message Heliox for delivery with a nonrebreathing face mask should be readily available in every operating room suite.
What is Stridor? Stridor is noisy inspiration from turbulent gas flow in the upper airway; it is often seen in upper airway obstruction. Stridor is potentially serious and always commands attention.
Causes of Stridor “Stridor is a symptom, not a diagnosis or disease, and the underlying cause must be determined.” emedicine.com
Causes of Stridor Photograph of an electrical wire stuck in the larynx of infant at the level of the vocal cords. The wire was removed at laryngoscopy. Interestingly, the child presented with minimal stridor. From the University of Bristol’s Foreign Body Hall of Fame.
Causes of Stridor Subglottic stenosis in a child. Treatment options include watchful waiting, tracheotomy, anterior cricoid split, laryngotracheal reconstruction, and cricotracheal resection. From http://www.meei.harvard.edu/shared/oto/pedi2.php
Causes of Stridor The triangular aperture of the normal infant larynx is about 7 mm x 4 mm, an area of 14 mm2. When intubation or an upper respiratory tract infection causes one millimeter of edema, the cross-sectional area is reduced to 5 mm 2, only 35% of normal. From www.childsdoc.org/spring98/stridor/ stridor.asp
Intubation The first issue is stridor whether or not intubation is immediately necessary. If intubation can be delayed a number of potential options can be considered, depending on the severity of the situation and other clinical details.
Nonintubation Options I Expectant management with full monitoring, oxygen by face mask, and positioning the head of the bed for optimum conditions (e.g., 45 - 90 degrees)
Nonintubation Options II Use of nebulized racemic epinephrine (0.5 to 0.75 ml of 2.25% racemic epinephrine added to 2.5 to 3 ml of normal saline) in cases where airway edema may be the cause of the stridor. (Cocaine in a dose not exceeding 3 mg/kg may also be used, but not together with racemic epinephrine.)
Nonintubation Options III Use of dexamethasone (Decadron ) 4 - 8 mg IV q 8 - 12 h in cases where airway edema may be the cause of the stridor; note that some time (in the range of hours) may be need for dexamethasone to work fully.
Nonintubation Options IV Use of Heliox (70% helium, 30% oxygen) The effect is almost instantaneous
Causes of Stridor Wherever possible, attempts should be made to immediately establish the cause of the stridor (e.g., foreign body, vocal cord edema, tracheal compression by tumor, functional laryngeal dyskinesia, etc.)
Diagnosis Stridor is usually diagnosed on the basis of history and physical examination, with a view to revealing the underlying problem or condition. Chest and neck x-rays, CT-scans, and / or MRIs may reveal structural pathology. Epiglottis with “thumb shaped” epiglottis
Diagnosis Flexible fiberoptic bronchoscopy can also be very helpful, especially in assessing vocal cord function of in looking for signs of compression or infection. http://www.tracheostomy.com
Diagnosis http://www.rale.ca The respirosonogram provides a visual representation of the content of the respiratory sound recording. Time is shown on the horizontal and frequency on the vertical axis. Sound intensity is indicated on a color scale, ranging from red (loud) over yellow and light green (medium) to dark green and gray (low). The breathing signal from Respitrace shows the rib cage [RC] movement at the top and the abdominal [AB] movement at the bottom (inspiration = up, expiration = down). Note: there is asynchronous movement of chest and abdomen during inspiration, clinically apparent as "indrawing". This stridor was recorded over the trachea of a 15 month old girl with croup.
http://www.trauma.org/imagebank/imagebank.html Case 17
“I had a great one a few years back. The patient had been stabbed in the back - 6 inch blade solidly embedded in his spine - spinal cord transected. We intubated him on his side because it was impossible to put him on his back. “ “ …The same goes for prone inductions. Although when I did it recently at the academic hospital spine unit I got the impression it hadn't been seen there....” Sandy Hancock, Adelaide, Australia Wisdom from GASNet 19 Jan 2004 Sandy Hancock
We had a guy come in with a big kitchen knife sticking out of his back (apparently he had complained about her cooking and the missus didn't take kindly to his criticism).... Surgeon insisted that we intubate (rapid sequence) in the lateral position.which we did most readily... THEN the surgeon says: "Bring in another OR table... I can't operate with him on his side!" He then places the tables side by side, patient supine with the knife handle sticking down between the tables! (and during the case he climbs under the OR tables and pulls the knife out from below!).... I just laughed...(and wished I had thought of that) Just another day at the office... WM J LOSKOTA, PhD, MD Wisdom from GASNet 19 Jan 2004 William Loskota
“Inducing prone and inserting an LMA is counter-intuitive, and it took me some time before I convinced myself it might be worth trying. I don't do it often, but it is easy, elegant and completely removes the risks of rolling an unconscious patient into the prone position. In addition, a paralyzed, intubated prone patient is arguably at more risk if the airway is lost than a spontaneously breathing one with an LMA. There are pros and cons for most techniques in anesthesia. It's all about finding your own balance.” Sandy Hancock, Adelaide, Australia Wisdom from GASNet 21 Jan 2004 Sandy Hancock
A 22 year old 980 pound (445kg) Caucasian male, 65 inches, BMI 163 Admitted to the ICU for respiratory failure. A tight-fitting CPAP / BIPAP system set for 20 cm H20. PaCO2 76 mm Hg → 107 mm Hg (pH 7.13), requiring 100% oxygen. Urgent tracheostomy
Technique IV access was established in the forehead –ultrasound image guided searches were unsuccessful to assist in central line placement Unsuccessful oral fiberoptic and nasal intubations LMA ProSeal placed without IV drugs. Anesthetized with Sevoflurane End-tidal CO2 levels 100 → 70 mmHg
Technique con’t Aintree stylette placed over fiberoptic bronchoscope, both placed through the LMA FOB was removed, followed by the LMA Parker size 7.5 ETT placed over the Aintree catheter Chin debulking procedure prior to tracheotomy 7.5 mm ID armored ETT placed in trachea