What are the effects of smoking cessation on patients undergoing anesthesia, specifically with Miller's anesthesia?

Smoking Cessation Effects in Perioperative Anesthesia

Smokers undergoing anesthesia and surgery should quit smoking at least 4-8 weeks preoperatively to significantly reduce respiratory complications, wound infections, and mortality, though immediate cessation is still beneficial and surgery should not be delayed for smoking cessation in urgent cases. 1

Perioperative Risks of Continued Smoking

Smoking substantially increases perioperative morbidity and mortality through multiple mechanisms:

Pulmonary complications:

• Increased risk of postoperative respiratory complications including pneumonia, atelectasis requiring bronchoscopy, prolonged ventilation (>48 hours), and need for reintubation 2
• Higher rates of pulmonary complications and prolonged postoperative intubation with longer ICU stays 2
• Interference with oxygen uptake, transport, and delivery during anesthesia 3

Cardiovascular effects:

• Elevated blood pressure, heart rate, and systemic vascular resistance 3
• Increased risk of myocardial ischemia during anesthesia, particularly with acute smoking within 12-48 hours of surgery 4
• Higher cardiovascular-related mortality in specific surgical populations 2

Wound healing complications:

• Delayed surgical wound healing and increased wound infection rates 2
• Impaired microcirculation affecting reconstructive procedures 2
• Higher rates of anastomotic leakage in colorectal surgery 2

Optimal Timing for Smoking Cessation

The evidence clearly demonstrates a time-dependent benefit:

• 4-8 weeks of preoperative abstinence is necessary to significantly reduce respiratory and wound-healing complications 2, 1
• Longer cessation periods confer progressively better surgical outcomes 2
• For elective reconstructive procedures (e.g., plastic surgery), delaying surgery 60-90 days after cessation provides optimal benefit 2

Important caveat: Short-term cessation (<4 weeks) has unclear or potentially paradoxical effects on respiratory complications due to temporarily increased mucous production 2. However, even brief cessation (24 hours) reduces carbon monoxide levels and improves oxygen delivery 3.

Approach to Smoking Cessation in Surgical Patients

For elective surgery:

• Identify all smokers at initial surgical consultation 1
• Recommend complete cessation at least 4 weeks before surgery 1
• Provide intensive interventions combining counseling and pharmacotherapy (nicotine replacement therapy or varenicline) 2, 5
• Weekly counseling sessions are most effective when started 4-8 weeks preoperatively 2

For urgent/cancer surgery:

• Encourage immediate cessation but do not delay necessary surgery for smoking cessation 2
• The limitations of evidence make it impossible to justify delaying urgent lung cancer surgery solely to pursue cessation 1
• Access to cancer surgery should not be restricted for smokers 2
• Cessation shortly before thoracic surgery is still associated with improved long-term survival 2

Role of Anesthesiologists

Anesthesiologists are uniquely positioned to lead smoking cessation efforts:

The perioperative period represents a "teachable moment" when patients are highly motivated to quit 6. Anesthesiologists should implement the "Ask, Advise, Connect" strategy 6:

• Ask all patients about smoking status at every preoperative visit 6
• Advise smokers strongly about health risks and benefits of quitting 6
• Connect patients directly to counseling resources (quitlines, pharmacists) via fax or electronic referrals 6

Critical gap in practice: While 85% of anesthesiologists ask about smoking status, only 31% advise about health risks, 23% advise quitting before surgery, and only 3% provide assistance to quit 7. This represents a significant missed opportunity.

Intraoperative Anesthetic Considerations

Monitoring challenges:

• Pulse oximeters may give incorrect readings in smokers 3
• Higher arterial to end-tidal CO2 differences complicate monitoring 3

Anesthetic management:

• Provide anxiolytic premedication with smooth, deep anesthesia to prevent complications 3
• Plan for increased oxygen therapy requirements in recovery 3
• Anticipate higher analgesic requirements postoperatively 3

Postoperative Management and Long-term Benefits

Immediate postoperative period:

• Smokers require more intensive respiratory support and oxygen therapy 3
• Higher rates of postoperative infections and sepsis-specific complications 2

Long-term outcomes:

• Smoking cessation after surgery substantially reduces subsequent major adverse cardiac events, MI, and death 2
• Benefits of cessation are durable even 30 years postoperatively 2
• Smoking cessation reduces mortality more than any other post-surgical intervention 2

Optimal cessation support: Counseling that begins during hospitalization and includes supportive contacts for at least 1 month after discharge increases long-term abstinence rates (OR: 1.65) 2. Intensive programs with 12-month follow-up achieve 62% abstinence rates versus 46% with minimal intervention 2.