Induction-intubation response--smokers vs non-smokers--

Tobacco smoking has been established to be a hazardous activity. Changing social attitude is bringing a decline in tobacco consumption but a significant proportion of patients presenting for surgery still continues to smoke, putting themselves at risk of perioperative complications. We evaluated induction-intubation response in 40 male patients (ASA-I) divided into two groups of 20, each consisting of smokers and non-smokers.

All patients received standard premedication and general anesthesia. Heart rate, blood pressure and rate-pressure product were measured prior to induction, just before intubation and at 1, 3, 5 and 10 minutes after intubation. Continuous electrocardiography (EKG lead II) monitoring was done. Carboxyhemoglobin and total hemoglobin were estimated at the time of securing venous access. Arterial blood gases were analysed 5 minutes before and after the tracheal intubation.

Incidence of arrhythymias (30%) was higher in smokers compared to non-smokers (10%). Mean carboxyhemoglobin (COHb) level in smokers was 3.81 +/- 2.17 gdL(-1) as compared to 2.95 +/- 1.33 gdL(-1) in non-smokers. Four patients who continued to smoke till the day of surgery had higher COHb levels (8.2, 5.9, 6, 8.8 gdL(-1)). PaO2 and PaCO2 levels were comparable in both groups.

During induction-intubation period, heart rate; systolic, diastolic and mean arterial pressure and rate-pressure product showed more pronounced fluctuations in smokers than in non-smokers (p < 0.05).