UBP 4.7 (Long Form): ENT – UPPP/Obstructive Sleep Apnea Flashcards Preview

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Flashcards in UBP 4.7 (Long Form): ENT – UPPP/Obstructive Sleep Apnea Deck (19)
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1

Intra-operative Management:

Which monitors would you place for this case?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

In addition to the standard ASA monitors, I would utilize a Foley catheter to monitor end-organ perfusion and fluid status, and a peripheral nerve stimulator to monitor neuromuscular function (assuming a neuromuscular blocking agent was administered).

Since his history of uncontrolled hypertension, dyspnea on exertion, and signs of right heart failure on echocardiography (i.e. right ventricular enlargement, elevated right ventricular systolic pressure) are suggestive of pulmonary hypertension and right heart failure,

I would also place an arterial line, pulmonary artery catheter, and a 5-lead EKG.

Recognizing that this patient with chronic hypertension is at increased risk of experiencing unstable hemodynamics during induction and intubation (hypotension and/or hypertension),

I would place the arterial line and pulmonary artery catheter prior to induction, if possible.

2

Intra-operative Management:

What is your plan for intubation?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

Given the risk of difficult ventilation and/or intubation associated with his obesity, severe OSA, short neck, micrognathia, and Mallampati III airway,

I would plan to perform an awake intubation,

recognizing that this may prove challenging with this very anxious patient.

Considering his high-risk airway and the extreme sensitivity of OSA patients to central nervous system depressant drugs, I would avoid any sedation, if possible.

My plan for intubation would include:

  1. administring metoclopramide and glycopyrrolate to facilitate gastric emptying and dry the upper airway, respectively;
  2. place the appropriate monitors, including an arterial line and pulmonary artery catheter;
  3. ensure the presence of difficult airway equipment;
  4. provide adequate airway analgesia, including --
    • nebulized lidocaine and peripheral blockade of the superior laryngeal and lingual nerves;
  5. place the patient in 30 degree reverse Trendelenburg position
    • (beneficial effects on pharyngeal tissue and pulmonary mechanics);
  6. perform a fiberoptic intubation and confirm proper endotracheal tube placement; and
  7. proceed with induction.

3

Intra-operative Management:

The patient, who would rather be asleep for intubation, tells you that he was successfully intubated under general anesthesia two years ago, without any problems. What would you say to him?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

I would tell him that, although his history of successful intubation is somewhat reassuring, it does not necessarily diminish his risk.

I would explain that I remain concerned because he has experienced significant weight gain and worsening symptoms of airway obstruction since being successfully intubated 2 years ago.

Given these concerns, I would tell him that an awake intubation without sedation remains the safest method of securing his airway, and I would reassure him that I would make every effort to make him comfortable during the procedure.

If he refused to undergo an awake intubation without sedation, or did not tolerate the procedure, I would cautiously sedate him using dexmedetomidine, with the goal of maintaining patient cooperation, spontaneous ventilation, and intact airway reflexes.

Other options for sedation would include -- benzodiazepines and opioid agonists.

Whatever the chosen agent, I would avoid polypharmacy and ensure the presence of appropriate reversal agents (i.e. flumazenil and/or narcan).

4

Intra-operative Management:

What type of endotracheal tube would you place? What does UPPP surgery involve?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

In deciding which type of endotracheal tube to use for the case,

I would discuss the planned surgical procedure, patient positioning, and endotracheal tube preference with the surgeon.

Usually, a standard or oral rae polyvinyl chloride (PVC) endotracheal tube is utilized.

However, if the surgeon was planning a laser-assisted uvulopalatopharyngoplasty (LAUPPP), a procedure where laser energy is used to eliminate pharyngeal tissue, I would consider using -- a laser resistance endotracheal tube.

Other procedures employed to treat severe obstructive sleep apnea, such as genioglossal advancement and maxillofacial procedures, may require other specialized airway devices.

For instance, a cuffed armored nasotracheal tube is often preferred for both mandibular and maxillomandibular surgery to allow for intra-operative occlusion of the mouth.

Surgery on the base of the tongue, on the other hand, requires the placement of a tracheostomy tube.

5

Intra-operative Management:

After successful awake intubation, the surgery begins.

How would you maintain anesthesia for this case?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

Given this patient's obesity and severe OSA,

the ideal anesthesia agents for maintenance of anesthesia would be -- short acting, without active or toxic metabolites, lack depressive effects on ventilation, and allow for a rapid return of airway reflexes.

Therefore, I would maintain anesthesia using a balanced technique including --

  • desflurane
    • (insoluble, lowest hepatometabolism of the volatile agents -- 0.02%, fastest wake-up and return of airway reflexes),
  • remifentanil
    • (rapid onset/offset, rapid metabolism by nonspecific esterases, inactive metabolites), and
  • cisatracurium
    • (Hoffman elimination -- morbidly obese patients often demonstrate liver dysfunction).

6

Intra-operative Management:

Assuming the surgeon is planning on using a laser for the procedure, woud you use an oxygen/nitrous oxide mixture?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

While the use of nitrous oxide provides some advantages, such as short duration of action and low blood-gas solubility coefficient,

I would NOT use it in this case due to the patient's apparent pulmonary hypertension (enlarged right ventricle and right ventricular systolic pressure > 40  mmHg).

Therefore, rather than nitrous oxide, I would use air to reduce the Fio2 as much as possible during laser use.

In reducing the Fio2, I would be balancing the risk of airway fire against the risk of hypoxia in this obese patient with increased oxygen demand and signs of right heart strain/failure.

7

Intra-operative Management:

Does the dosing of intravenous anesthetic agents need to be adjusted due to the patient's obesity?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

Theoretically, lipophilic drugs (benzodiazepines, opioids, barbiturates, etc.) have a larger volume of distribution in obese patients secondary to increased deposition into body fat, making an initial loading dose based on total body weight (TBW) reasonable.

By the same reasoning, a larger volume of distribution increases clearance time of lipophilic drugs, making reduced doses during maintenance a reasonable strategy.

---

The volume of distribution of hydrophilic drugs, on the other hand, is less affected by increased fat stores.

Therefore, these drugs (e.g. NMBAs) should, theoretically, be dosed based on ideal body weight (IBW).

In practice, however, the pharmacologic effects of obesity on anesthetic drugs are extremely complicated and do not always mirror expectations.

Therefore, a reasonable approach is to calculate your initial dose based on IBW and titrate additional dosing to clinical effect.

-----

Clinical Note:

  • Specific Drugs:
    • Propofol -- Induction: Ideal BW; Maintenance: Total BW
    • Pentothal -- Induction: Total BW; Maintenance: Total BW
    • Midazolam -- Loading Dose: Total BW; Maintenance: Total BW
    • Succinylcholine -- Induction: Total BW; Maintenance: Total BW
    • Vecuronium/Rocuronium -- Induction: Ideal BW; Maintenance: Ideal BW
    • Atracurium/Cisatracurium -- Induction: Total BW; Maintenance: Total BW
    • Fentanyl/Sufentanil -- Loading Dose: Total BW; Maintenance: Ideal BW
    • Remifentanil -- Induction: Ideal BW; Maintenance: Ideal BW

8

Intra-operative Management:

Suddenly the airway pressure alarm goes off and the bellows do not fill in between breaths. What do you think is going on?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

Low airway pressures and inadequate gas flow to fill the ventilation bellows is consistent with -- an anesthesia circuit leak.

While the most likely locations for a significant leak include the circle system, Y-piece, endotracheal tube connection, or the endotracheal tube cuff, I would also consider -- the gas flow meters, CO2 absorber, scavenging system, and ventilation bellows.

While attempting to locate the leak, I would switch to hand ventilation, increase my fresh gas flows, and deliver a Fio2 of 100%.

If hand ventilation via the current circuit proved inadequate, and I was unable to quickly identify the leak, I would attempt to ventilate the patient using an AMBU bag with 100% oxygen.

If ventilation remained inadequate, I would consider the possibility of a ruptured ETT cuff and prepare for replacement of the damaged ETT over a tube exchanger.

9

Intra-operative Management:

The surgeon reports that he has accidentally cut a hole in the endotracheal tube and there is a large leak in the oropharynx. What would you do?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

I would --

  • immediately call for help,
  • increase my fresh gas flows,
  • ensure the delivery of 100% oxygen, and
  • hand ventilate the patient.

If ventilation and oxygenation proved inadequate despite high gas flows, I would --

  • advance the ETT under fiberoptic visualization until the leak was past the vocal cords.

If that failed to improve oxygenation, I would --

  • ask the surgeon to prepare for a possible emergency tracheostomy,
  • have the operating room personnel prep and drape the patient's neck, and
  • attempt to exchange the ETT over an exchange catheter adapted for oxygen insufflation.

10

Intra-operative Management:

After a brief episode of hypoxia, you successfully exchange the ETT over an exchange catheter. The hypoxia resolves, but the blood pressure is now 66/31 mmHg.

What is your differential diagnosis?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

The timing of his hypotension, immediately following an episode of hypoxia, suggests the possibility that the patient is experiencing --

  • myocardial ischemia, myocardial infarction, a cardiac arrhythmia, and/or acute heart failure.

Other potential causes of hypotension include --

  • excessive anesthesia, tension pneumothorax (central line was placed), and anaphylactic reaction.

In addressing this hypotension, I would --

  • quickly evaluate the EKG, arterial blood pressure, PA pressure, cardiac output, systemic vascular resistance, SaO2, and end-tidal CO2.

Depending on my findings, I would --

  • discontinue any volatile agent to attenuate the reduced systemic vascular resistance associated with volatile agents;
  • place the patient in the trendelenburg position to improve preload (increased venous return to the heart);
  • start a fluid bolus; and
  • consider administering an inotrope and/or an appropriate vasoactive drug.

11

Intra-operative Management:

The patient's ECG tracing shows the following: (see picture)

What would you do?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

This ECG tracing demonstrating an irregularly irregular rhythm with narrow QRS complexes and absent P waves is representative of atrial fibrillation.

Since this appears to be new onset atrial fibrillation, associated with hemodynamic instability, I would --

  • call a code,
  • start chest compressions, and
  • perform synchronized cardioversion using 100 joules and progressing to 200 joules, 300 joules, and 360 joules as necessary to convert the patient to a sinus rhythm.

--- ??????? --- Review ACLS protocol of this...

12

Intra-operative Management:

Could you administer Amiodarone for pharmacologic cardioversion?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

This patient with significant hemodynamic instability may not tolerate the administration of antiarrhythmic drugs, which may lead to bradycardia and worsening hypotension.

However, if it were determined that the benefits of pharmacologic cardioversion outweighed the risks, I would administer a 150 mg intravenous bolus of Amiodarone over 10 minutes (preferred drug with significant heart disease), followed by a 1 mg/minute infusion for 6 hours, and a 0.5 mg/minute infusion for 18 hours (maximum dose: 2.2 g/24 hours).

At the same time, I would prepare to quickly address any subsequent deterioration in hemodynamics.

13

Post-operative Management:

How would you manage post-operative pain in this patient?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

My goal is to achieve adequate analgesia while minimizing the risk of post-operative respiratory depression.

Recognizing that patients with OSA are extremely sensitive to the respiratory depressant effects of opioids, I would -- utilize non-narcotic options, such as -- local anesthetics (i.e. regional anesthesia and local wound infiltration), NSAIDs, and ice as much as possible.

If I believed that intravenous narcotics were necessary, I would use a short acting agent such as fentanyl, administered via PCA without a basal infusion (continuous background infusions should be avoided or used with extreme caution secondary to an increased risk of respiratory depression).

Regardless of the chosen method of post-operative pain control, I would provide -- supplemental oxygen, head-up positioning, and continuous positive airway pressure (CPAP) or non-invasive positive pressure ventilation (NIPPV) to further reduce the risk of respiratory compromise.

-----

Clinical Notes:

  • The 2005 ASA Practice Guidelines for the Perioperative Management of Patient with OSA recommend -- post-operative CPAP and NIPPV for all patients being treated pre-operatively with these modalities.
  • The surveyed consultants were equivocal regarding the use of post-operative CPAP or NIPPV in patients who had NOT been previously treated with these same modalities.

14

Post-operative Management:

After successful extubation the patient is taken to the PACU.

How would you monitor this patient's respiratory status post-operatively and when would you consider it safe to discharge him home?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

The 2005 ASA Practice Guidelines for the Perioperative Management of Patients with OSA recommends that -- patients with OSA should be monitored post-operatively with continuous pulse oximetry until they can maintain room air oxygen saturation above 90% while asleep.

The panel also recommends that -- these patients be monitored for a median of 3 hours longer than non-OSA patients, and

for at least 7 hours after the last episode of airway obstruction or hypoxemia while breathing room air in an unstimulating environment.

----

Therefore, I would NOT recommend this patient be discharged home until his pain was controlled without narcotics, airway swelling had decreased, and baseline oxygen saturation was maintained during sleep while breathing room air.

15

Post-operative Management:

30 minutes later you are called stat to the PACU where you find the staff attempting to mask ventilate your patient. He is hypoxic with a Sao2 of 78%. What would you do?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

I would immediately call for help, the emergency airway cart, and the ENT surgeon.

I would then ensure the patient was in the head-up position (to improve respiratory mechanics), take over mask ventilation, place an oral or nasal airway, provide a two handed jaw thrust, and attempt to mask ventilate with 100% oxygen.

If ventilation were still inadequate, I would place an LMA and consider re-intubation.

At the same time, I would continuously monitor the patient for signs of cardiovascular deterioration.

16

Post-operative Management:

Bag mask ventilation is ineffective, intubation attempts are unsuccessful, and he has become bradycardic. What would you do?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

I would ask the ENT surgeon to proceed with an emergency surgical airway while I continued to attempt to ventilate the patient.

If a surgeon were not available, I would perform a cricothyroidotomy by placing a needle through the cricothyroid membrane until air was aspirated, passing a wire through the needle, making a skin incision next to the wire, and advancing a tracheostomy or endotracheal tube over the wire.

Once the airway was in place, I would confirm ventilation by auscultation of all lung fields and observation of adequate chest rise and consistent end-tidal CO2.

17

Post-operative Management:

After successful tracheostomy and resuscitation, the patient remains mildly hypoxic with a SaO2 of 89% while breathing 100% oxygen. What do you think is going on?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

There are several possible explanations for this obese patient's continued hypoxia following an emergency surgical airway, such as --

  • aspiration of blood and/or gastric contents during resuscitation,
  • bronchospasm,
  • pulmonary edema
    • (heart failure or negative pressure pulmonary edema),
  • atelectasis,
  • hypoventilation,
  • pneumothorax,
  • malpositioned cricothyroidotomy tube,
  • pulmonary embolism, and
  • acute heart failure.

In addressing his hypoxia, I would auscultate the lungs; confirm proper cricothyroidotomy tube placement and adequate ventilation; evaluate his PA pressure and cardiac output; and order a CXR.

Depending on my findings, I would -- administer a bronchodilator, adjust the cricothyroidotomy tube, place a chest tube, optimize his hemodynamics, and/or adjust ventilator settings.

18

Post-operative Management:

Physical exam reveals diffuse pulmonary crackles and CXR shows generalized pulmonary edema that was not present preoperatively.

What could have caused this?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

GIven his OSA, HTN, and recent hypoxic event,

his pulmonary edema most likely represents --

either negative pressure pulmonary edema or left heart failure.

In the case of upper airway obstruction, sustained ventilatory effort against a closed glottis could have resulted in high negative intrapleural pressure with subsequent movement of fluid from the pulmonary capillary bed into the alveoli.

On the other hand, hypoxia-induced ischemia, dysrhythmias, and/or hypertension may have led to left heart failure with subsequent pulmonary edema.

Other potential causes or contributing factors would include -- fluid overload, aspiration, and anaphylaxis.

19

Post-operative Management:

Assuming this were negative pressure pulmonary edema, how would you manage his condition?

(A 48-year-old obese male is scheduled for elective uvulopalatopharyngoplasty (UPPP).

The patient has a history of 12 months progressive weight gain (85 pounds) and excessive daytime somnolence. His wife reports extremely loud snoring at night with agitation and confusion upon waking. He lives a sedentary lifestyle and has significant dyspnea with exertion.

PMHx: HTN, Hypothyroidism, Hiatal hernia, Depression

Meds: HCTZ, lisinopril, synthroid, prevacid, and zoloft

Allergies: Sulfa

PE: Vital Signs: Wt = 104 kg, height = 172 cm, BP = 165/90 mmHg, HR = 86 bpm

Airway: Mallampati III, short neck, micrognathia, full cervical range of motion

CV: Loud second heart sound (P2)

Lungs: Decreased breath sounds bilaterally, no wheezing

Labs: Hgb = 19 gm/dL; K = 3.8 mEq/L

EKG: Right axis deviation, possible LVH

Echo: Enlarged right ventricle, right ventricular systolic pressure > 40 mmH

Polysomnography: 280 episodes of apnea or hypopnea lasting greater than 10 seconds, recorded over an eight hour period of sleep.)

Recognizing that the treatment of negative pressure pulmonary edema (NPPE) is supportive,

I would -- ensure a patent upper airway, provide supplemental oxygen, and positive pressure ventilation.

If his oxygenation did not improve, I would consider the addition of positive end-expiratory pressure (PEEP) to promote alveolar expansion.

While diuretics are sometimes utilized in the treatment of this condition, their use is controversial, and I would not administer these drugs unless hemodynamic data indicated hypervolemia.