Welcome back to the journal review — this month we're in Dermatologic Surgery's September 2026 issue, and I've got four pieces worth your time: a quick clinical innovation, a major practice-guideline update, and two reconstructive conundrums that hit the kind of defects that actually make you pause in clinic. Let's get into it.

First up is a Point piece — essentially a brief clinical innovation report — on a calculator for maximum local anesthetic dosing in dermatologic surgery. The clinical problem here is one you already know intuitively: local anesthetic systemic toxicity is rare but catastrophic, and while we all have the per-agent maximum dose numbers roughly memorized — the five-hundred-milligram ceiling for lidocaine with epinephrine, for instance — the existing online tools are surprisingly bad at handling the scenarios we actually encounter. The authors point out that popular calculators like MDCalc and the Johns Hopkins SafeLocal app don't account for combining two different agents, don't adjust for bicarbonate buffering, and honestly weren't built with dermatologists in mind. That gap matters most in exactly the cases we do all the time — long multistage Mohs cases, or hidradenitis excisions and deroofings — where you might be running lidocaine with epinephrine for immediate anesthesia and then layering in bupivacaine with epinephrine for extended postoperative pain control, and the cumulative volume can genuinely creep toward the ceiling.

So what they built is not a new clinical study but a tool. They took published maximum-dose guidelines and a separate recommendation that when combining agents, the combined dose shouldn't exceed the maximum of any single agent — meaning if you've used half the max of drug A, you get at most half the max of drug B. They fed those rules into ChatGPT-4o, had it generate a web app, and then had the authors and three dermatologists validate the output for accuracy before publishing it as supplemental content. The calculator lets you pick two agents, adjust for epinephrine and bicarbonate, and it spits out both the individual maximums and the adjusted combined maximum, plus a graph showing safe combination zones. Worth flagging explicitly what the authors themselves flag: there isn't actually robust evidence for true safe maximum dosing when agents are combined, so this is a reasonable-consensus tool, not a validated safety threshold, and it still needs to be filtered through the patient's comorbidities and medication list.

Practically, this is a nice-to-have, not practice-changing in the sense of altering your technique — but it's a genuinely useful bedside or pre-op reference, especially for anyone doing high-volume HS surgery or long multistage Mohs days where you're mentally tracking two anesthetic running totals. Worth downloading and keeping on your phone; not worth restructuring your anesthesia protocol around.

Now to the substantial piece this month — the updated Antibiotic Prophylaxis in Dermatologic Surgery Advisory Statement, APDSAS 2025, from Campbell, Otley, and colleagues at Mayo, updating their foundational 2008 statement. This is best thought of as a guideline update article rather than a primary study, built on a structured literature review feeding a multidisciplinary consensus process — they ran two PubMed search strings, one pairing dermatologic surgery and Mohs with antibiotic prophylaxis, another pairing SSI with dermatologic surgery, netting roughly two hundred and two hundred fifty articles respectively, screened by title and abstract and then reviewed in depth. There's no statistical modeling here to teach — this is evidence synthesis and expert consensus, so the methodological lesson is more about guideline construction than biostatistics: note how they explicitly structure recommendations around three distinct clinical questions — infective endocarditis prophylaxis, prosthetic joint infection prophylaxis, and surgical site infection prophylaxis — because the risk calculus and evidence base differ substantially across those three.

On infective endocarditis, nothing has changed. The AHA's 2020 guidance mirrors its 2007 predecessor, so their recommendation stands exactly as it did in 2008 — prophylaxis only when the procedure breaches oral mucosa or is performed on infected skin, and only in patients with defined high-risk cardiac conditions, things like prior endocarditis, prosthetic valves, unrepaired cyanotic congenital heart disease, or a repaired congenital defect with prosthetic material within the past six months.

Prosthetic joint infection prophylaxis is where it gets more nuanced, though the bottom-line threshold hasn't moved — prophylaxis is still only for mucosal or infected-skin procedures. What's changed is the underlying decision algorithm, now aligned with the newer American Academy of Orthopaedic Surgeons and American Dental Association appropriate-use criteria. Instead of a single risk factor triggering prophylaxis, it's now a multivariable decision incorporating immunosuppression status, diabetes control, and history of prior PJI requiring reoperation. The authors offer a genuinely useful heuristic for daily practice: if a patient has none of three red flags — prior PJI needing reoperation, immunosuppression, or poorly controlled diabetes — you don't need to consult the full algorithm at all, prophylaxis isn't warranted regardless of surgical site. If any of those three are present and you're working on mucosal or infected skin, that's your cue to pull up the full decision tree. And critically, they note there's insufficient evidence to skip oral prophylaxis just because you're using intraincisional clindamycin in your local anesthetic — those are treated as independent, non-interchangeable strategies.

The SSI section is where the real texture is, and where the evidence is messier. They cite a systematic review showing meaningfully elevated SSI risk with local flap repairs and skin grafts compared to simpler closures — roughly a three-fold increase for flaps and nearly three-fold for grafts, which is a clinically real signal, not noise. Immunosuppression as an SSI risk factor is murkier — one study found roughly a doubling of risk in solid organ transplant patients, but several others failed to replicate that, though a more recent meta-analysis did find a significant association overall, so the weight of evidence is tilting toward immunosuppression mattering. Second-intention healing and SSI risk remains genuinely unsettled — one study found increased risk, particularly on the lower extremity approaching ten percent, while another found no correlation at all. And useful for anyone doing lower-extremity work: a recent study found no benefit whatsoever from preoperative prophylactic antibiotics for lower-extremity dermatologic surgery specifically, despite that site carrying the highest infection rates in the literature.

There's also a grab-bag of practice-pattern shifts worth knowing even though they're not the antibiotic-prophylaxis question per se — a move away from sterile gloves toward clean gloves given evidence of no benefit and lower cost, emerging interest in preoperative nasal decontamination, and real support for chlorhexidine decolonization before lower-extremity surgery. And on intraincisional clindamycin specifically — the data show it reduces SSI risk, but the authors flag emerging bacterial resistance among skin pathogens as a real limitation on how much you should lean on it going forward, and they explicitly state there's no consensus yet on whether it should ever replace systemic prophylaxis.

The authors' own stated limitation is important: the evidence base underlying essentially all of these SSI recommendations remains predominantly retrospective, so what you're getting is a best-available-evidence synthesis, not randomized-trial-level certainty.

Practically, this one is close to practice-changing, particularly the PJI algorithm — if you've been using a simpler single-risk-factor mental model for prosthetic joints, it's worth actually sitting down with the full decision tree they provide, because the appropriate-use criteria have genuinely shifted toward multivariable assessment. The endocarditis recommendations require no change at all. And the lower-extremity finding — no benefit from preoperative prophylactic antibiotics despite that site's higher infection rates — is worth internalizing directly, since it's the kind of counterintuitive, exact-figure-driven finding that should change reflexive prescribing habits on shin and pretibial cases.

Now to two Reconstructive Conundrum case reports — no statistics here, just technique and clinical reasoning, so we'll walk through the defect, the options considered, and the chosen solution for each.

The first is a large medial cheek defect after Mohs. A seventy-five-year-old woman with a thin lentigo maligna melanoma, Breslow depth of point-three millimeters, underwent six stages of Mohs with melanocytic immunohistochemistry to clear margins, leaving a five-by-five-centimeter defect on the right medial cheek. The complicating factors were the defect's sheer size plus patient-specific anatomy working against the surgeon — a voluminous cheek, minimal baseline rhytids, and unusually limited surrounding laxity, which knocks out several of your usual go-to options. They talk through the differential: a Pac-Man flap can circumferentially recruit tissue but tends to leave long curvilinear scars crossing aesthetic boundaries and may simply not reach far enough in a full cheek with minimal laxity; transposition flaps like a bilobed pivot across intact skin, which shortens your effective advancement vector and risks distorting adjacent subunits. They ultimately chose an anterior-based cervicofacial rotation-advancement flap, designed with a superior incision along the palpebromalar groove to the temple specifically to eliminate vertical tension vectors and reduce ectropion risk, extended down through the preauricular crease avoiding hair-bearing skin, and carried inferiorly behind the neck for a broad, vascularity-preserving pedicle. Dissection stayed in the subcutaneous plane superficial to SMAS and platysma to protect the facial and marginal mandibular nerves. Worth noting technically: they describe a "Stamp-n-tack" technique — serial load-bearing tacking sutures placed from the flap underside to progressively drape and inset the flap while distributing tension and closing dead space — plus periosteal anchoring at the inferior orbit, both aimed squarely at ectropion prevention. A Burow's triangle was repurposed as a temporary full-thickness graft for the secondary infra-auricular defect. At one year, outcome was excellent, with only two sessions of intralesional triamcinolone needed for a small area of hypertrophic scarring below the lobule. The authors cite comparative literature showing superficial and deep-plane cervicofacial flaps have similarly low rates of necrosis, ectropion, and hematoma — so the superficial-to-SMAS plane they chose isn't sacrificing outcome for safety, it's genuinely the lower-risk option for nerve injury without a described trade-off in flap survival. For your own practice, the actionable takeaway is the algorithm itself: when you hit a wide medial cheek defect with an unfavorably tight, voluminous cheek, cervicofacial rotation-advancement should move up your list ahead of Pac-Man or transposition options, and the "Stamp-n-tack" tacking-suture concept is a transferable technical pearl for any large rotation-advancement flap where you're worried about ectropion or dead space.

The second conundrum is a small but anatomically tricky defect spanning the alar base and upper cutaneous lip. An eighty-year-old woman with a morpheaform basal cell carcinoma resected in a single Mohs stage left a ten-by-ten-millimeter defect straddling the right alar base and upper cutaneous hemilabium. Small defect, but the subunit-crossing nature is the whole problem: a straightforward lip advancement flap would have been the obvious move for a pure lip subunit defect, but the authors show explicitly why that fails here — elevating the lip subunit alone would distort the alar base anatomy and function, essentially borrowing tissue from the wrong place to patch the wrong problem. Instead they used a myocutaneous island transposition flap taken from the upper edge of the nasal ala itself, undermining the hemilabium with incisions along the lateral nasolabial fold, then rotating the island flap superomedially through an arc in the sixty-to-hundred-twenty-degree range to reconstruct the three-dimensional thickness of the alar base directly, rather than trying to borrow contour from adjacent lip tissue. Secured with deep absorbable anchoring sutures and fine nonabsorbable sutures superficially. They're transparent about alternative options they didn't use — a Burow's graft for structural support, a V-Y advancement re-establishing alar rim curvature, or a tunneled cheek island flap along the melolabial crease — and even offer a bit of self-critique, noting the lip rotation component might have been positioned slightly higher within the apical triangle to sharpen the definition between the alar base, lip, and melolabial fold. Result at two to three months was described as good functionally and cosmetically, with the closure lying along the nasolabial fold so the scar blends into an existing natural crease. The teaching point that generalizes well beyond this single case: for defects straddling the alar base and lip, matching tissue to its subunit of origin — pulling thickness for the ala from ala-adjacent tissue rather than recruiting the lip to do double duty — is what preserves the boundary and avoids blurring the aesthetic junction, and it's a genuinely useful option to add to your mental toolkit alongside the Burow's graft and V-Y approaches for this specific junctional defect type.

That wraps the September issue. To summarize where your attention is best spent: the antibiotic prophylaxis advisory statement is the one worth sitting down with in full, especially the revised prosthetic joint algorithm and the lower-extremity antibiotic non-benefit finding; the anesthetic calculator is a handy pocket tool for your bigger cases; and both reconstructive conundrums offer transferable technical reasoning — cervicofacial rotation-advancement with the Stamp-n-tack tacking method for large, tight medial cheek defects, and subunit-matched myocutaneous island transposition for alar-base-and-lip junctional defects. Thanks for listening, and I'll see you next month.