This has been reposted from another blog. Quite interesting.


Clinical Case of the Month: You are in an operating room in a freestanding plastic surgery center giving general anesthesia to Patient A, and you are called by the PACU nurse because Patient B in the PACU is having stridor. The PACU Patient B is a healthy 39-year-old female, one hour status-post liposuction, and her anesthesiologist has signed out to you. Patient B is now cyanotic. You are the only anesthesiologist for miles, and both Patient A and B need you. What do you do?

Discussion: You perch the circulating R.N. from your O.R. in front of the monitors, tell her to let you know if anything changes, and you leave the O.R. to attend to the patient in the PACU. Is there any alternative? Are you going to stand there with stable Patient A while Patient B dies of airway obstruction thirty feet away from you?

When you arrive in the PACU, you see a young woman sitting up in bed making loud crowing sounds with every inspiration. Her oxygen saturation is 89% on 4 liters of nasal oxygen, and her heart rate is 110. Her husband is standing at the bedside, and his eyes are bugging out of his head watching his wife gasp for air. The PACU nurse is standing on the other side of the patient, and her eyes are bugging out almost as far as the husbandís.

You ask the nurse to open an Ambu bag and connect it to the oxygen source. You ask the husband to leave the room while you evaluate and treat his wife. A second nurse escorts him out. You listen to the patientís lungs, and her breath sounds are normal except for upper airway stridor. The exam of her mouth and neck is normal. You take additional history, and learn that she had a three hour intubation for a prone liposuction, and was extubated without complication. She received 20 mg of meperidine 45 minutes earlier, and no other medication was given in PACU. The stidor started two minutes earlier, when her oxygen saturation decreased from 100% to the high 80ís.

Your diagnosis is laryngospasm of unclear etiology. You apply an anesthesia mask over her face, deliver 100% oxygen via the Ambu bag, and attempt to apply continuous positive airway pressure (CPAP) to break her laryngospasm. You ask her to cough hard to clear secretions that may be lodged on her vocal cords. Within a minute the stridor passes, and her oxygen saturation returns to 100%. Her other vital signs are normal, and her skin is free of urticaria. You review her anesthesia record, and it is unremarkable. The patient feels significantly better, and you return to the OR to check on your patient who is still under general anesthesia. The OR circulating nurse reassures you that Patient A is fine, and nothing changed during your absence.

Two minutes later, the PACU nurse calls in a panic again, because Patient B is having stridor again. You run to the PACU, and repeat the assessment and therapeutic moves you made in the paragraphs above. Your diagnosis is post-intubation laryngospasm. You can not rule out post-intubation vocal cord paralysis. You treat with 8 mg of IV dexamethasone. There is no vaporized racemic epinephrine in the facility. The patient is moving air well, but intermittently crowing with stridor. You call 911 for an ambulance, and call the ER attending at the nearest hospital to tell him you are coming over. You place a third call to the Respiratory Therapy service at the hospital, and tell them to meet you at the ER with a racemic epinephrine treatment for the patient.

Patient Aís surgery ends in the next 10 minutes, as the ambulance crew arrives and prepares Patient B for transport. You extubate Patient A and deliver her in stable condition to the PACU just in time to join the Emergency Medical Techs as they load Patient B into the ambulance. You load your pockets with vials of propofol and succinylcholine, a laryngoscope, and two syringes, and follow her into the ambulance. The siren blares, and the ambulance drives Code 3 to the ER. The patientís intermittent stidor continues, with oxygen saturation in the low 90ís on a 100% non-rebreather mask.

In the first twenty minutes in the ER, the Respiratory Therapist arrives and gives a nebulized racemic epinephrine treatment to Patient B. Within the next twenty minutes her symptoms resolve. Her husband arrives, and he looks a lot happier than the first time you saw him, too.

You make a phone call. Minutes later, one of the nurses from the freestanding plastic surgery center drives up in their car to give you a ride back to where your automobile is parked back at the surgery center.

Sound impossible? Guess again. This entire scenario occurred three months ago, a mile or two from Stanford hospital.

The diagnosis of post-extubation stridor is more common in newborn infants after prolonged or multiple intubations, but it occurs in adults as well. In one series of 112 extubations of adults in an ICU in France, the prevalence of post-extubation stridor was 12% (Jaber S, Intensive Care Med. 2003 Jan;29(1):69-74). Occurrence after extubation post-surgery is less common. When laryngospasm occurs in the OR immediately post-intubation, we are all taught to treat the patient with 100% oxygen and CPAP by face mask. The laryngospasm usually clears as the patient awakens from anesthesia and mounts a strong cough to clear secretions from the larynx.

When stridor occurs in the PACU of a hospital, the established medical therapy is nebulized racemic epinephrine (Vaponefrin), .5 ml of a 2.25%solution q 3-4 hours given by Respiratory Therapy, and a dose of dexamethasone 4 Ė 8 mg IV (Miller, Anesthesia, 2005, pp 2817, 2538). Nebulized epinephrine acts as both an alpha and beta adrenergic agonist, and has both vasoconstrictor and bronchodilator properties.

The lack of Respiratory Therapy in freestanding surgery centers is another of the issues that differentiates them from in-hospital ambulatory surgery centers. The plastic surgery center that suffered through this episode has now purchased the equipment to deliver nebulized epinephrine post-op. It may be years, or decades, before they get an opportunity to use it. A more important lesson is that the perioperative care of surgical patients is multi-faceted, and no one is better prepared to diagnose or treat problems than an anesthesiologist. If you practice anesthesia in freestanding surgery centers long enough, you too will experience a ride in an ambulance to the ER. Hopefully your story will have a happy ending, as our Clinical Case of the Month did.

Our patient was discharged home from the ER after a stable four hour observation period, and she had no further problems at home.