For each study we extracted the number of postoperative complications for both continuing smokers and recent quitters. We also extracted data on the study period, duration of abstinence in recent quitters, whether their smoking status was biochemically validated, study design, the type of surgery, and the postoperative complications that were assessed Table.
Where a study collected relevant data but did not report them in a form usable for our analysis, we contacted the authors. The quality of the included articles 1 , 2 , 5 , 11 , 22 - 26 was assessed according to national guidelines for undertaking systematic reviews 27 and using indicators of susceptibility to bias specific for the purpose of the review. The key issue for our purpose concerns the reliability of classifying patients as recent quitters. Misclassification of smoking status presents by far the most serious risk of bias.
Real differences could be diluted or even masked if the classification of abstinence was inaccurate. Studies that validated self-reported abstinence biochemically thus present the best evidence available. This consideration is included in the Table.
It reflects the reliability of data of interest to the present review rather than the overall quality of the studies, which had mostly different purposes and priorities. The included studies differed in a number of other ways, but we are not aware of any other feature that would exaggerate or diminish the difference between the 2 study groups in a systematic manner.
The included studies used a range of study designs, but the key comparison of postsurgical complications in patients who stopped smoking shortly before surgery and those who continued to smoke is largely independent of study design and not affected by it. For example, while 2 studies randomized smokers to either a stop-smoking intervention or a control procedure, some smokers in the control group stopped smoking and many in the intervention group did not.
For our purpose, the comparison of the randomized groups is less informative than the comparison of quitters and continuing smokers across both conditions both studies provide the necessary information. For these reasons, no quality points were assigned to study designs.
The different designs would not be expected to differ in accuracy of detecting postsurgical complications or produce any systematic bias in reporting complications in continuing smokers and recent quitters. Similarly, as the subanalysis of interest to us was not the main focus of the included studies, publication bias was unlikely: there was no obvious reason that would lead researchers or publishers to prefer one result over another. Data extracted from the included studies were entered into the RevMan Review Manager program version 5.
We assessed statistical heterogeneity using the I 2 statistic. Where there was significant heterogeneity, a random-effects model was used. The first meta-analysis included all available studies to check for any effects of recent quitting, beneficial or detrimental.
We repeated this analysis using only studies with validated self-reported abstinence and least risk of bias. Finally, we analyzed separately studies that focused specifically on pulmonary complications to assess possible detrimental effects in this particular area.
A total of patients participated in the relevant studies. The characteristics of the 9 studies that met the inclusion criteria are listed in the Table. Two additional studies were close to meeting the inclusion criteria.
One of these reported data separately for patients who stopped smoking 2 to 4 weeks prior to the operation and those who quit earlier. However, the analysis included a comparison of smokers who stopped smoking within 2 weeks before the operation with continuing smokers.
This makes the interpretation of the findings difficult, and the study is not included in the meta-analyses results reported herein. However, including this study in the relevant meta-analyses did not alter the results. The second study concerned pulmonary complications following resection of lung cancer. The incidence of complications was not significantly different in recent quitters and continuing smokers 6. The study is not included in the meta-analysis, but its inclusion does not affect the results.
Two other excluded studies require a special mention because they have been cited as demonstrating risks of recent quitting and an explanation of such risks. Self-reported smoking reduction may not reflect any real change in the inhaled volume of smoke. Even when there is a genuine reduction in the number of cigarettes, the reduction is usually undermined by compensatory smoking 31 , 32 ; this finding is therefore difficult to interpret. Yamashita et al 33 compared intraoperative sputum production among recent quitters, continuing smokers, and nonsmokers.
Patients were categorized into having or not having a high sputum volume. Only 1 of the 9 included studies reported a significant result, and this was in favor of recent abstainers.
Because there is substantial heterogeneity between these studies, the result needs to be interpreted with caution. Figure 3 presents the results of the 3 reports that validated self-reported abstinence and had the highest quality scores. The results again show no significant benefit or detrimental effect of recent quitting compared with continued smoking, but there is once more substantial heterogeneity in the data.
The effect of smoking cessation on postoperative pulmonary complications is shown in Figure 4. The results are homogeneous, and they show no significant increase in risk in those who stopped smoking less than 8 weeks prior to surgery compared with those who continued smoking. The present analysis does not support the suggestion that quitting smoking less than 8 weeks before surgery has a negative impact on surgical outcomes.
A hypothetical explanation of the presumed risks of quitting before surgery, as suggested by Warner et al 11 and repeated by others, 13 is based on an assumption that stopping smoking leads to a decrease in coughing and an increase in sputum production. Both of these claims remain unconfirmed. Smoking seems to suppress rather than enhance cough reflex sensitivity. The investigation found no difference between recent quitters and continuing smokers. There are several limitations to this systematic review.
The results are based on observational data. Quitting behavior may be determined by the same factors that determine postoperative outcomes. For example, patients who stop smoking may be more likely to access postoperative care, perhaps masking a detrimental effect of recent quitting.
Conversely, those with more serious illness may be more likely to stop smoking, possibly obscuring beneficial effects of recent quitting. Another potential limitation is that our search covered only studies in English. Our meta-analyses combined different types of surgical procedures and various definitions of postoperative complications.
The chance of anesthetic gas impairing macrophage function—possible even in patients with healthy lungs—is far greater for smokers. This has spurred the ASA to action.
Did you know that you can get reimbursed for counseling qualified Medicare patients on smoking cessation? G —Smoking and tobacco use cessation counseling visit: intermediate, minutes. For more on the ASA program to help physicians help their patients stop smoking,.
Clearing the smoke: the scientific rationale for tobacco abstention with plastic surgery [review]. Plast Reconstr Surg. The outcome of perioperative wound infection after total hip and knee arthroplasty.
Int Orthop. Abstinence from smoking reduces incisional wound infection: a randomized controlled trial. Ann Surg. Theadom A, Cropley M. Effects of preoperative smoking cessation on the incidence and risk of intraoperative and postoperative complications in adult smokers: a systematic review. Tob Control. Effect of smoking on early complications after elective orthopaedic surgery. J Bone Joint Surg Br. Rodrigo C. The effects of cigarette smoking on anesthesia [review].
As a result, your body becomes deprived of the oxygen it needs to repair wounds and build healthy new tissue. Smoking also causes narrowing of the blood vessels, which can prevent blood, oxygen nutrients from reaching your healing wound.
Smoking thickens your blood. That makes it more difficult for blood to travel through your blood vessels—especially if they. If you are a smoker, your thickened blood raises your risk of developing a blood clot in your legs.
If a blood clot travels from your legs to another part of your body, it could cause a heart attack, stroke, or pulmonary embolism a blood clot in your lungs. Your blood contains cells called neutrophils that help fight infection. Smoking causes these cells to lose some of their infection-fighting power, which can double your chances of getting an infection after surgery compared to a non-smoker.
If you develop , it will not only slow your recovery, but you may need to take antibiotics, have another surgery, or spend more time in the hospital. The chemicals found in cigarettes can increase the amount of inflammation, or swelling, throughout your body. After surgery, this extra swelling can cause smokers to experience more pain than non-smokers.
If your surgeon thinks you may be at risk for smoking-related complications during or after surgery, he or she will can refer you to a Surgery Optimization Clinic. There, you will meet with a skilled nurse practitioner. They will perform a complete exam to find out more about your overall health. In addition to a head-to-toe exam, you will get pre-surgery education about lowering your risk for problems. Together, you and your nurse practitioner will make a step-by-step plan to help you achieve your goal of quitting smoking.
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