Conundrums in Ambulatory Anesthesia I

Girish P. Joshi, MBBS, MD, FFARCSI Professor of Anesthesiology and Pain Management

Director of Perioperative Medicine and Ambulatory Anesthesia

THE UNIVERSITY OF TEXAS

SOUTHWESTERN MEDICAL CENTER

DALLAS

Parkland Hospital, Dallas, Texas

One of the Busiest Trauma Centers in US

Parkland Hospital, Dallas, Texas Conflict Of Interests Research Grants and/or Honoraria

•  Pfizer Inc.

•  Baxter Pharmaceuticals

•  Cadence Pharmaceuticals

•  Pacira Pharmaceuticals

•  Edward Life Sciences

Objectives

•  Describe identification of preoperative risk factors in the obese including sleep apnea

•  Illustrate the importance of appropriate selection of adult obese and sleep apnea patients scheduled for ambulatory surgery

•  Discuss anesthetic risks including difficult airway in this patient population

•  Specify criteria for discharge of these outpatients

Are patients with OSA suitable for

ambulatory surgery?

•  Scientific literature on safety and perioperative management of OSA patients is sparse and of limited quality

ASA-Scoring System For OSA Patients

A.  Severity of OSA (0-3 pts) B.  Invasiveness of surgery/anesthesia (0-3 pts) C.  Requirements for postoperative opioids (0-3 pts) •  Overall score (0-6): A + greater of B or C

–  Score > 4 increased risk from OSA –  Score ≥ 5 significantly increased risk from OSA - Not

suitable for ambulatory surgery •  Intra-abdominal and upper airway surgery are not

suitable for ambulatory surgery ASA Practice Guidelines: Anesthesiology 2006; 104: 1081-93

Joshi GP et al: Anesth Analg 2012; 115: 1060–8

SAMBA-OSA Systematic Review

•  No difference in complications between OSA and non-OSA patients undergoing ambulatory surgery

•  Emphasis on preoperative diagnosis

•  Emphasis on use of non-opioid analgesics to minimize opioid use

•  Emphasis on postoperative care particularly use of CPAP after discharge Joshi GP et al: Anesth Analg 2012

OSA Patients NOT Suitable For Ambulatory Surgery

•  Patients with OSA without optimized comorbid conditions

•  Opioid dose cannot be limited by using non-opioid analgesics and/or regional/local anesth

•  Patients’ inability to follow post-discharge instructions including compliance with CPAP

Joshi GP et al: Anesth Analg 2012

Clinical Diagnosis of OSA: STOP-BANG Questionnaire

Chung et al: Anesthesiology 2008; 108: 812-21

•  Loud snoring •  Daytime somnolence •  Observed apnea •  Hypertension •  BMI>35 kg/m2 •  Age > 50 yrs •  Neck circumference >40cm •  Male •  ≥3 yes =high risk of OSA

Positive Predictive Value (%)

STOP-Bang Score and AHI

Farney et al: J Clin Sleep Med 2011; 7: 459-65

Chung F et al. Br. J. Anaesth. 2012;108:768-75

Predicted Probabilities For AHI and STOP-Bang Score

Should Patients Suspected Of OSA Undergo a Sleep Study?

•  No evidence preop CPAP improves outcome

•  Optimal duration of preop CPAP unknown

•  Poor compliance with CPAP

•  Proceed with a presumed OSA diagnosis

•  Sleep study only if severe OSA and significant comorbidities (CHF, pulm HTN, metabolic synd)

Preoperative Selection of a OSA Patient For Ambulatory Surgery

Patient With Known OSA Patient With Presumptive

Diagnosis of OSA

Optimized Comorbid Conditions

AND Able to use CPAP after

discharge

Patients With Non-optimized

Comorbid Conditions

Optimized Co-morbid Conditions

AND Postoperative opioids can be limited by using non-

opioid analgesic techniques

Not Suitable For Ambulatory Surgery,

may benefit from diagnosis and treatment

Proceed With Ambulatory Surgery

Proceed With Ambulatory Surgery

Joshi GP et al: Anesth Analg 2012; 115: 1060-8

No guidance can be provided for airway surgery

Perioperative Complications in OSA Patients

All patients (n=2370)

Severe OSA (n=746)

BMI 43 ± 8 45 ± 8

ASA Physical Status 1 & 2 65% 41%

ASA Physical Status 3 & 4 35% 59%

Transient desaturation SaO2 <93% 30% 40%

Postop stay (phase 1 & 2) 127 ± 31 126 ± 31

Deaths 0 0

Resp failure/reintubation 0 0

Readmission/Transfer within 30 days 20 (0.08%) 5 (0.5%)

Kurrek et al: Obes Surg 2011

Unplanned Admission After Ambulatory Surgery in OSA Patients •  Preop screening for OSA

•  OSA patients observed for 4 h postop

•  Discharge home if no episodes of apnea, airway obstruction, and SaO2<90%

•  Patient admitted if unwilling or unable to wear CPAP, airway procedure, inadequate analgesia with increasing and unpredictable use of parenteral opioids

Bryson GL et al: Can J Anaesth 2012; 59: 842-51

OSA Does Not Increase Unplanned Admission After Ambulatory Surgery

•  Severity of OSA not associated with increased unplanned admission

OSA

(n=191)

No OSA

(n=204)

Duration of postop stay (median, CI) h 7 (5-8) 6 (5-8)

Unplanned admission (median, CI) % 7 (5.1-8.9) 5.6 (4.1-7.1)

Bryson GL et al: Can J Anaesth 2012; 59: 842-51

Postoperative Sleep Patterns and OSA

Location and invasiveness of the surgical procedure Degree of pain and need for opioids

Surgical Stress, Anxiety, and Pain

Sleep deprivation and fragmentation (reduce REM sleep)

Rebound REM sleep (lasts for several days after surgery)

Airway obstruction and Life threatening apnea

Rosenberg et al: J Clin Anesth 1994; 6: 212-6

Sleep Disturbances After Fast-Track Hip and Knee Arthroplasty

Krenk L et al. Br. J. Anaesth 2012;109:769-75

•  Patients undergoing fast-track THR & TKR

•  Procedure performed under SA and postop analgesia with multimodal non-opioids

•  No REM sleep on POD1 •  REM returned to preop

levels on POD4 •  No association between

opioid use, pain scores, inflammatory response and sleep disturbance

Postoperative Apnea-Hypopnea Index (AHI) in OSA Patients

Chung F et al: Anesthesiology 2009; 111: A255

Advice Patient, Family, Caregiver: Patients on Preoperative CPAP

•  Bring CPAP device to the facility, unless one is available at the facility

•  Use CPAP while sleeping, even during the daytime

•  Use CPAP for several days postop

Joshi GP et al: Anesth Analg 2012

Advice Patient, Family, Caregiver: Patients With Presumptive Diagnosis of OSA

•  Avoid sleeping in supine position, if possible

•  Limit opioid use, emphasize deleterious effects of opioids

•  Follow-up with their primary physician for possible sleep study

Joshi GP et al: Anesth Analg 2012

S u m m a r y

•  OSA patients are at high risk of periop complications

•  Unrecognized OSA, is more likely to cause problems

•  Discuss with surgeon and patients/family regarding concerns with opioid use

•  OSA patients may be at risk for several days postop

•  Patients on CPAP must use it at home

•  Admit patient when in doubt

Is there a weight

limit for ambulatory

surgery?

PRISMA Diagram Showing Identification of Included References

Excluded by title review: 17,426 Papers considered for abstract and/or full-text review: 138

Exclusions = 118 - Irrelevant papers- excluded by abstract/ full-text review: 101 - Reviews: 14 - Case reports and correspondence: 3

Studies included in qualitative analysis: 24 Systematic review: 1 Prospective observational trials: 13 Retrospective chart review: 10

Primary search results: 17,564 records

Additions Hand search and cross reference: 4

Results

•  Studies included in the systematic review not included in this review (no duplication)

•  106,119 patients (prospective cohort trials = 62,476 and retrospective trials = 43,643)

•  Bariatric surgery population = 39,548, does not include systematic review patients (n=2549)

•  Obese had increased respiratory events –  O2 desaturation, need for O2 supplementation

–  Stridor/laryngospasm, airway obstruction

Results

•  No differences in unanticipated admission rate

–  Obese and non-obese cohorts

–  Studies of bariatric and non-bariatric surgery

•  BMI in non-bariatric surgery studies around 30

•  BMI in bariatric surgery studies was around 40 –  Rigorous preoperative preparation

•  Super obese (BMI>50) higher risk of complications

Is there a weight limit for ambulatory surgery?

•  BMI>50 may increase perioperative risks •  Determinants of perioperative outcome

–  Comorbid conditions (OSA, obesity-related hypoventilation syndrome, pulmonary hypertension, resistant systemic hypertension, significant CAD, resistant CHF, h/o DVT or PE, h/o bleeding disorder, chronic renal failure on dialysis)

–  Invasiveness of surgical procedure –  Surgeons’ experience –  Facility capability

Difficult Airway Management

Difficult Airway: Facial Trauma

Difficult Airway: Angioedema

Kissing Tonsils

Difficult Airway: Complications

•  Despite introduction of supraglottic devices and videolaryngoscopes

•  New guidelines from ASA and ESA

•  Airway disasters still a major source of brain damage and death

Cook TM, et al: Br J Anaesth 2011; 106: 617-31 ASA Difficult airway guidelines: Anesthesiology 2013; 118: 251-70

ASA Difficult Airway Algorithm

Anesthesiology 2013; 118: 251-70

Airway Management Algorithm

Brambrink AM, Hagberg CA: Airway Management Principles and Practice. St. Louis, Mosby-Year Book

Difficult Airway Algorithm

Brambrink AM, Hagberg CA: Airway Management Principles and Practice. St. Louis, Mosby-Year Book,

Mask Ventilation Prior to NMB

•  Unlikely that patients could woken up to restore spontaneous ventilation before significant hypoxia

•  Could ‘safe practice’ be compromising safe practice? –  Calder I et al. Anaesthesia 2008; 63: 113–5;

Priebe H-J. Anaesthesia 2008; 63: 671-2

NMB Facilitates Tracheal Intubation

•  Analysis of a Danish Anesthesia Database of 103,812 planned tracheal intubations by direct laryngoscopy found that avoiding NMB was associated with difficult tracheal intubation –  Lundstrøm LH, et al. Br J Anaesth 2009; 103: 283–90

•  Most patients with difficult MV receive NMB –  Kheterpal S, et al. Anesthesiology 2009; 110: 891–7 –  Langeron O, et al. Anesthesiology 2000; 92: 1229–36 –  Kheterpal S, et al. Anesthesiology 2006; 105: 885–91

Effect of NMB on Mask Ventilation

•  Double-blind, placebo-controlled trial (n=90)

•  After induction with propofol 2 mg/kg and fentanyl 1 µg/kg

•  Randomly received saline or rocuronium

•  Mask ventilation performed, graded at 2 min

•  Roc significantly improved mask ventilation –  Greater improvement in patients with difficult mask

ventilation (Warters Scale ≥ 3) Warters RD et al: Anaesthesia 2011, 66: 163–7

UK: Fourth National Audit Project

•  “Where facemask or laryngeal mask anaesthesia is complicated by failed ventilation and increasing hypoxia the anaesthetist should consider early administration of further anaesthetic agent and or a muscle relaxant to exclude and treat laryngospasm.”

•  “No anaesthetist should allow airway obstruction and hypoxia to develop to the stage where an emergency surgical airway is necessary without having administered a muscle relaxant.” Cook TM, et al: Br J Anaesth 2011; 106: 617-31

Induction of Anesthesia

•  Head up position – 20-30º –  airway collapse, lung volume -  Tagaito Y et al: Anesthesiology 2010;113:812-8

•  “Stacking” –  Chin higher than chest

•  Preinduction CPAP –  Improves pharyngeal airway patency -  Isono et al: Anesthesiology 2005;103:489-94

•  Preoxygenation –  End-tidal oxygen >90% –  Tanoubi I et al: Can J Anaesth 2009;56:449-66

Difficult

Airway Management: Mask Ventilation

Tracheal intubation

•  Optimize head position •  Two hand ventilation •  Oral/nasal airway

MV before muscle relaxants

Preprocedure Preparation

Success

Induction of GA Mask Ventilation

NO NO

Difficult Tracheal Intubation

Obtain videolaryngoscope/fiberscope

Airway Management: Tracheal Intubation

Limit number of attempts

Invasive Airway Access •  Transtracheal jet ventilation •  Cricothyroidotomy

•  Optimize position •  Bougie •  Change blades •  Supraglottic Device •  Videolaryngoscope •  Fiberscope Consider return to spont resp

Consider awakening

Call for help

Difficult Airway Management: Common Pitfalls

•  Airway difficulty not recognized –  Inadequate assessment –  Overconfident –  Impulsive decisions

•  Risk of aspiration not recognized •  Repeated attempts at intubation •  When in doubt, err on side of caution

–  Choose most conservative option

Difficult Mask Ventilation

•  Male gender

•  Presence of beard

•  Mallampati 3 or 4

•  Sleep apnea

•  Neck radiation

Kheterpal, et al. Anesthesiology 2009; 110:891-7

•  Limited mouth opening (<25 cm) •  Inability to protrude mandible •  Mallampati score ≥3 •  Thyromental distance <65 cm •  Neck circumference >40cm •  Range of motion of head and neck (cannot touch

tip of chin to chest or cannot extend neck)

Difficult Direct Laryngoscopy: No Single Factor Predicts

Awake Tracheal Intubation

•  H/o previous difficult intubation

•  Mouth opening <25mm

•  Severe fixed flexion deformity of cervical spine –  Neck radiation, ankylosing spondylitis, rheumatoid

•  Pharyngeal and/or laryngeal pathology –  Abscess, hematoma, edema, tissue disruption, tumor

Awake tracheal intubation

Awake look with videolaryngoscope

Known or Anticipated Difficult Airway

GA with spontaneous breathing • Inhalation induction • Propofol ± remifentanil • Dexmedetomidine + ketamine

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No Single Factor Predicts Difficult Airway

Videolaryngoscopes: Difficult Laryngoscopy and Failed Direct Laryngoscopy

Healy DW, et al: BMC Anesthesiology 2012; 12: 32

Videolaryngoscopes

Healy DW, et al: BMC Anesthesiology 2012; 12: 32

S u m m a r y

•  Identify difficult airway –  Mask ventilation –  Supraglottic device placement –  Videolaryngoscope –  Tracheal intubation

•  Identify risk of aspiration •  Determine need for awake intubation •  Determine choice of muscle relaxant

–  Rocuronium vs. succinylcholine •  Prepare for plans B and C

–  Extra help and equipment

Thank You. Questions

The Art of Anesthesia