Does Secondhand Smoke Contribute To Delayed Post-Op Healing?
Doctors in various professions have noted the deleterious effects of smoking on post-op healing. A new study says smokers take almost twice as long to heal as nonsmokers and also sheds light on another aspect of smoking: the delayed effects of healing in those exposed to secondhand smoke. Conducted at the Oakwood Hospital System in Michigan, the study, presented as a poster at the American College of Foot and Ankle Surgeons Annual Scientific Meeting, tracked 46 patients who had undergone Austin bunionectomies. The group was comprised of 17 smokers, 17 nonsmokers and 12 people exposed to secondhand smoke. The patients underwent a modified Fagerstrom test for nicotine dependency and also underwent urine tests to measure nicotine levels, according to the study. Authors say the average time of post-op healing was 69 days in non-smokers, 78 days in people exposed to secondhand smoke and 120 days in smokers. “Our study results were not a surprise except for the effects of secondhand smoke,” notes study co-author Lawrence Fallat, DPM, a Clinical Assistant Professor within the Department of Family Medicine at the Wayne State University School of Medicine in Detroit. “There are many studies in the orthopedic literature that indicate delayed healing and nonunion are much higher in smokers. The surprise is that secondhand smoke also delays bone healing just as if the patients were primary smokers.”
Keys To Patient Education
How can one best communicate to patients the effects of smoking on postoperative healing? When patients with fractures seek elective bone surgery, Dr. Fallat explains to them that if they smoke, they will take longer to heal and may experience nonunions. Peter Wilusz, DPM, explains to patients that smoking has an adverse effect on healing as carbon monoxide binds to red blood cells so oxygen cannot bind and reach the tissues, making it difficult for tissues to heal. “Taking a little extra time to explain the details of postoperative complications (wound dehiscence, infection, amputation, etc.) associated with smoking may open the eyes of a few reasonable patients,” says Dr. Wilusz, a Diplomate of the American College of Foot and Ankle Surgeons. Furthermore, if the procedure is elective, Dr. Wilusz advises telling patients that they must quit smoking 10 weeks before surgery and also advises DPMs to measure pre-op nicotine levels prior to proceeding with surgery.
What About Future Directions For Research?
Where is further research headed? Dr. Fallat is currently conducting a retrospective study on the effects of smoking on the diabetic foot. He notes that he expects to discover a higher incidence of ulcers and amputations in diabetic smokers due to the vasoconstrictive effects of nicotine. Dr. Wilusz says research has shown that patients with diabetes who smoke have a risk of cardiovascular complications that is 40 times greater than that of nonsmoking patients with diabetes. He notes one can likewise expect more post-op complications in diabetic smokers. Dr. Wilusz does not perform elective procedures on patients with diabetes who smoke. “I feel there needs to be evidence-based research showing definitive facts that the risk of elective surgery outweighs the benefit of proceeding with surgery in the diabetic smoking population,” maintains Dr. Wilusz. “We as physicians need to take on a greater responsibility to recognize, educate and intervene on behalf of this group of individuals.”
Study: Patients With ESRD And PAD Have Poor Prognosis
By Brian McCurdy, Senior Editor A recent study in Angiology concludes that end-stage renal disease implies a poor prognosis for patients with stage IV peripheral arterial disease (PAD). Researchers compared 16 patients with ESRD who were hospitalized with foot gangrene to 24 patients with normal creatininemia who were hospitalized for foot gangrene due to PAD. The study found those with ESRD had more frequent extensive arterial calcifications due to a higher level of the calcium phosphorus product and impaired microcirculatory perfusion. Kazu Suzuki, DPM, CWS, notes the “vast majority” of ESRD patients in his practice have PAD (defined as skin perfusion pressure (SPP) values below 50 mmHg) in one or both lower limbs. As he notes, the question is usually focused on the severity of the PAD as opposed to whether the patients have it. Dr. Suzuki cites Okamoto’s PAD study of hemodialysis patients in the American Journal of Kidney Disease in 2006 that demonstrated that 46 of 72 legs screened with a CT-angiogram showed significant PAD, which was defined as the leg artery stenosis of more than 75 percent vascular lumen. When one considers the natural disease progression of arthrosclerosis, Dr. Suzuki says “it makes a lot of sense” that the incidence of polyvascular diseases like PAD coincides with ESRD.
Why ABI Tests Are Not Enough When It Comes To PAD And ESRD
“In my opinion, PAD has been often overlooked and under-diagnosed because we used to rely on ABI tests that are often falsely negative in diagnosing PAD in diabetes and/or ESRD patients,” says Dr. Suzuki, the Medical Director of the Tower Wound Care Center at Cedars-Sinai Medical Towers in Los Angeles. He notes the Okamoto study determined the ABI test was only 29.9 percent sensitive for PAD. David E. Allie, MD, concurs, noting that traditional ABIs and duplex ultrasounds “are often unreliable” because of heavy vascular calcifications, making PAD screening poor in the ESRD patient population. He has found new multichannel CTA very helpful in identifying ESRD patients who are at risk for developing critical limb ischemia (CLI), saying CTA provides excellent information that facilitates revascularization.
Emphasizing Aggressive Treatment
When patients with ESRD present in Dr. Suzuki’s clinic, he pursues a thorough workup with a SPP/PVR monitor, works closely with vascular specialists to facilitate surgical revascularization of ischemic limbs, and aggressively pursues limb salvage. “The key for the conscientious clinician is to identify high-risk patients, and to advocate the prevention of ESRD with intensive medical treatment, by controlling body weight, blood glucose, cholesterol, hypertension, and also advocating smoking cessation,” comments Dr. Suzuki. Dr. Allie agrees about the importance of aggressive treatment. While ESRD patients are more challenging to treat and their results are always “somewhat poorer” than patients without ESRD, Dr. Allie points out that many studies have shown that one can and should treat ESRD patients aggressively. Dr. Allie says patients with ESRD are part of an overall “hypercoagulable” patient population compared to patients with only PAD, and treating physicians need to adopt appropriate strategies that take this factor into account. The fact that many ESRD patients also have diabetes complicates the picture, according to Dr. Allie, the Director of Cardiothoracic and Endovascular Surgery at Cardiovascular Institute of the South in Lafayette, La. “Overall, our personal experience in this patient population is positive but they will require much more expertise and commitment. Wounds can be closed and limbs can be saved that would overall be lost,” maintains Dr. Allie. “Remember, once an amputation occurs in this patient population, less than 50 percent will be alive in two years and one in three will require a contralateral amputation so a limb saved is a life extended.” As Dr. Allie notes, treatment strategies for ESRD patients versus non-ESRD patients have little variation once patients present with CLI, except those with ESRD have more vascular calcifications that one must address. Dr. Allie emphasizes the need for more aggressive treatment for revascularization and wound closure since ESRD patients tend to be slow healers, even with revascularization, given the possible immunosuppression due to baseline renal disease, anemia, diabetes, etc. “If there was ever a patient population in which early diagnosis and prevention should be mandatory, it is the ESRD patient,” says Dr. Allie. “It is my opinion that each ESRD patient should have at least a yearly evaluation by a podiatrist and peripheral vascular specialist.”
Study Offers Insights On Failed Limb Salvage Attempts
By Brian McCurdy, Senior Editor When it comes to limb salvage surgery for dysvascular diabetic patients, failures occasionally occur, leading to multiple returns to the operating room before a definitive amputation is ultimately performed at the transtibial or higher level. One recent study has attempted to refine the criteria used to select candidates for aggressive limb salvage interventions who are most likely to benefit from such care. The study, presented as a poster at the American College of Foot and Ankle Surgeons Annual Scientific Meeting, evaluated the records of 40 patients who had undergone amputations between 1995 and 2005. One group had partial amputations that healed while the second group had failed partial amputations and needed more proximal amputations. Researchers note the amputations were due to complications of diabetes as well as peripheral arterial disease (PAD). They noted the most common site of the first surgery was at the digital level with a Wagner 2 wound classification. In the proximal amputation group, 75 percent had no pedal pulses, according to the study. Study authors also say all patients had diabetes and they detected neuropathy and peripheral vascular disease in both groups. Furthermore, the study found evidence of renal disease in 50 percent of the patients with proximal amputations. Due to the disproportionate number of patients in the two groups, researchers concluded that there was no significant statistical data. However, they did note a trend toward impaired renal function and an absence of pedal pulses in those with proximal amputations. When it comes to patients with renal failure, study co-author Ronald Sage, DPM, cites the importance of glucose control, protein restriction and medical management with ACE inhibitors and diuretics, which are best supervised by a nephrologist. However, even when these patients are treated, Dr. Sage maintains that renal failure tends to be slowly progressive and will eventually require dialysis or a renal transplant. Preventing renal failure requires optimized glucose control from the onset of diabetes, according to Dr. Sage, a Professor and Chief of the Section of Podiatry at the Department of Orthopaedic Surgery and Rehabilitation at the Loyola University Stritch School of Medicine. To manage vascular disease in those with an absence of pulses, Dr. Sage suggests smoking cessation, aspirin, clopidrogrel and statins. As he notes, surgical interventions include angioplasty, atherectomy and bypass surgery. “Although glucose control is important, prevention requires elimination of tobacco use, exercise, control of hypertension and lipid management with diet or medication,” says Dr. Sage. Researchers are attempting to measure the effects of multiple comorbidities in this patient population in order to refine the patient selection criteria for limb salvage intervention, according to Dr. Sage. However, he notes that greater numbers of patients are necessary before researchers can report any definitive data analysis.
In Brief
Schwarz Pharma says its phase III trial with lacosamide for the treatment of diabetic neuropathy showed statistically significant superiority in comparison to placebo. The study, involving 106 patients, showed lacosamide was well tolerated, according to the company. Schwarz Pharma says the drug’s dual mode of action is the selective enhancement of sodium channel slow inactivation and the modulation of CRMP-2 (collapsing response mediator protein 2). MacroChem Corporation recently announced the start of a 40-patient, multicenter, phase II study of EcoNail, a topical antifungal treatment for onychomycosis. The company notes that the topical combines econazole and MacroChem’s enhancer SEPA.
