Mythbusters in Microsurgery: Evaluating Evidence and Debunking Dogma—A Practical Review: Part I

Abstract

Background:

Reconstructive microsurgery has become a cornerstone in the management of complex tissue defects, yet many perioperative practices remain rooted in tradition rather than robust evidence. Persistent complications and variable protocols necessitate systematic evaluation of these dogmas to guide best practices.

Methods:

We conducted a comprehensive literature review of all major databases to identify all studies addressing techniques, perioperative care, monitoring, patient selection, and recovery in reconstructive microsurgery. Relevant studies were assessed and graded using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) system. When available, meta-analyses and updated systematic reviews were prioritized; individual studies within such analyses were not separately reported to avoid redundancy.

Results:

Eight commonly held perioperative myths were critically appraised. Evidence demonstrates that judicious intraoperative vasopressor use does not increase flap compromise or loss. Perioperative nonsteroidal anti-inflammatory drugs, including cyclo-oxygenase-2 inhibitors, do not raise the risk of hematoma or thrombosis. Routine therapeutic anticoagulation or dextran use provides no benefit in flap survival and increases bleeding risk. High-dose perioperative steroids are associated with greater flap and wound complications. Extended antibiotic prophylaxis beyond 24 hours postoperatively does not reduce surgical site infections. Negative-pressure wound therapy is safe for free flaps. Most vascular compromises occur within 48–72 hours, supporting step-down monitoring thereafter. Finally, advanced age, diabetes, obesity, or immunosuppression due to solid organ transplantation or other reasons should not preclude patients from getting microsurgical reconstruction.

Conclusions:

Many entrenched perioperative practices in microsurgery lack contemporary evidence. Evidence-based adoption of updated protocols can minimize complications, standardize care, and improve outcomes in reconstructive microsurgery.

Takeaways

Question: Are common perioperative practices in reconstructive microsurgery evidence-based?

Findings: Current evidence supports judicious vasopressor use; nonsteroidal anti-inflammatory drugs, including cyclo-oxygenase-2 inhibitors, do not raise hematoma or thrombosis risk; routine therapeutic anticoagulation/dextran offers no flap survival benefit and increases bleeding risks; high-dose steroids are linked to more complications; antibiotics beyond 24 hours do not reduce surgical site infections; negative-pressure wound therapy is safe on free flaps; most vascular events occur within 48–72 hours, supporting step-down monitoring thereafter; and advanced age, diabetes, or obesity alone are not contraindications to reconstructive microsurgery.

Meaning: Dogmas need to be replaced with evidence-based protocols to improve outcomes in microsurgical reconstruction.

INTRODUCTION

Reconstructive microsurgery has evolved dramatically since its inception in the 1960s, transforming the landscape of complex tissue reconstruction. The first successful free flap using microvascular anastomosis was reported by Daniel and Taylor¹ in 1973, laying the groundwork for modern microsurgical techniques. In the ensuing decades, advancements in surgical instruments, microscope technology, and flap design enabled increasingly sophisticated reconstructions, including perforator flaps and composite tissue transfers.² Today, reconstructive microsurgery is a cornerstone of multidisciplinary care in trauma, cancer, and congenital anomalies.

Despite these advancements, major complications persist, leading to suboptimal outcomes and increased healthcare costs.^3–8 Historical practices in intraoperative techniques, perioperative care, monitoring, patient selection, and recovery are often rooted in tradition rather than contemporary evidence. This 2-part practical review aimed to evaluate the 17 most frequently cited such practices listed in Table 1. In part I, we focused on 8 practices related to perioperative care, monitoring, and patient selection, and provided an evidence-based foundation for revising clinical protocols. By synthesizing high-quality studies and grading their evidence levels, this practical review aimed to dispel outdated practices and promote standardized, evidence-based approaches in reconstructive microsurgery.

Table 1.

List of All Practices

Category	Myth/Practice
Intraoperative technique	Vein grafts in free flap reconstruction have an unacceptably high failure rate
	Always perform 2 venous anastomoses; 1 is not enough
	Artery-first anastomosis is superior to vein-first.
	Papaverine is indispensable to prevent vasospasm
	Muscle flaps are inherently superior for osteomyelitis coverage
	Recipient vessels must avoid the “zone of injury”
Perioperative care	Intraoperative vasopressors harm free flaps
	NSAIDs (eg, ketorolac/ibuprofen/celecoxib) cause hematoma or thrombosis
	Routine therapeutic anticoagulation improves microvascular patency; dextran is beneficial
	High-dose perioperative steroids improve free flap outcomes
	Prolonged postoperative antibiotics reduce SSI after free flaps
	NPWT is unsafe on free flaps
Monitoring	Free flaps require 5–7 d of ICU-level hourly monitoring
Patient selection	Older/diabetic/obese patients are poor candidates for microsurgery
Recovery	Caffeine consumption compromises free flaps
	Strict postoperative bed rest is necessary to prevent flap failure
	Showering with a drain in place is associated with a higher risk of SSI

METHODS

A comprehensive literature review was conducted using PubMed, Embase, Scopus, and Web of Science. Search terms included relevant keywords and medical subject headings tailored to intraoperative techniques, perioperative care, monitoring, patient selection, and recovery in reconstructive microsurgery. (See appendix, Supplemental Digital Content 1, which displays the application of the GRADE [Grading of Recommendations Assessment, Development, and Evaluation] framework and A–C recommendation grades, https://links.lww.com/PRSGO/E805.) Studies were evaluated and graded using the GRADE system for evidence quality (Supplemental Digital Content 1, https://links.lww.com/PRSGO/E805).⁹ To avoid redundancy, individual studies included in existing meta-analyses or systematic reviews were excluded from reporting, prioritizing meta-analyses and updated follow-up studies in the evidence synthesis.

INTRAOPERATIVE VASOPRESSORS

To improve intraoperative hypotension during microvascular flap reconstruction, several vasopressors are used.¹ However, there remains concern about the theoretically increased risk of flap ischemia due to vasoconstriction.^10,11 In response, some surgeons manage intraoperative hypotension with fluid resuscitation rather than vasopressor support.¹¹

Current evidence debunks this dogma. Large retrospective series have found no difference in flap compromise or loss between vasopressor-treated patients and controls.¹² For example, a 10-year review of 5671 flaps at Massachusetts General Hospital showed equivalent flap success rates with vasopressors and lower venous congestion than in no-pressor cases, and another series noted ephedrine use correlated with fewer flap complications, whereas phenylephrine had no negative effect.¹³ Furthermore, 2 meta-analyses confirmed that vasopressors do not increase flap failure or thrombosis; in fact, vasopressor use was associated with slightly higher flap success rates, consistent with findings in head and neck free flap reviews.^11,14 Current guidelines (including enhanced recovery after surgery protocols) encourage judicious vasopressor use to maintain blood pressure without fear of compromising the flap.

The notion that vasopressors cause free flap failure has been refuted by strong clinical data. Although most available studies are observational (level II–III evidence), consistent findings across high-volume cohorts and meta-analyses provide strong support for this conclusion.^11,14 In the absence of randomized trials, this evidence is considered sufficient to establish that careful vasopressor use is safe in free flap surgery. Overall, the quality of evidence supporting this consensus is high (level II), and this myth is now debunked.

Recommendation

Judicious intraoperative vasopressor use is safe in microsurgery (Evidence Level—Moderate; Strength of Recommendation—B).

NONSTEROIDAL ANTI-INFLAMMATORY DRUGS AND HEMATOMA

Nonsteroidal anti-inflammatory drugs (NSAIDs) have traditionally been avoided in the perioperative period of microsurgery due to concerns that their platelet-inhibiting effects could lead to bleeding, hematoma formation, or even anastomotic thrombosis.¹⁵ This cautious approach was based on general surgical experiences, where NSAIDs were linked to increased bleeding risk, and on the pharmacological fact that NSAIDs reduce platelet aggregation.^15,16

Many plastic surgeons feared that using an NSAID (such as ketorolac) after a free flap could cause a hematoma under the flap or at the anastomosis, which in turn might compress the pedicle or necessitate a reexploration.¹⁶ As a result, postoperative pain control often relied solely on opioids, avoiding NSAIDs to mitigate this theoretical bleeding risk.¹⁷

Recent studies have not borne out a significant increase in bleeding due to perioperative NSAID use in patients undergoing free flap reconstruction. A 2019 systematic review and meta-analysis (15 studies, 3064 patients) compared flap outcomes with and without NSAIDs and found no statistically significant difference in postoperative hematoma or bleeding complications between the NSAID groups and controls.¹⁷ There were no differences in bleeding or hematoma rates between patients who received ketorolac, ibuprofen, or the cyclo-oxygenase-2 (COX-2) inhibitor celecoxib and patients who received no NSAIDs. Multiple clinical series in breast reconstruction have also examined NSAID use. Notably, studies evaluating COX-2 selective NSAIDs (such as celecoxib) in microsurgical breast reconstruction reported no higher flap loss rates (and even lower hematoma rates) in patients who received a COX-2 inhibitor compared with those who received a nonselective NSAID (eg, ketorolac) or no NSAID at all.¹⁸

Importantly, nonselective NSAIDs have also shown safe profiles in patients undergoing microsurgery.¹⁹ Likewise, in head and neck free flap surgery, protocols incorporating routine ketorolac have demonstrated no increase in flap thrombosis, failure, or hematoma, while actually improving pain control and reducing opioid requirements.¹⁶ These consistent clinical findings have debunked the historical assumption that NSAIDs inevitably cause bleeding or microvascular thrombosis in free flaps.

Recommendation

NSAID/COX-2 inhibitor use is safe following microvascular reconstruction (does not increase hematoma or thrombosis risk) (Evidence Level—Moderate; Strength of Recommendation—B).

PERIOPERATIVE ANTICOAGULATION USE

Traditionally, many microsurgeons routinely administered systemic anticoagulants after microvascular free flap surgery such as intravenous heparin infusions, antiplatelet agents such as aspirin, or even low-molecular-weight dextran, aiming to prevent thrombosis of the anastomosed vessels.¹¹ By the 1980s and 1990s, aggressive anticoagulation beyond standard deep vein thrombosis (DVT) prophylaxis had become dogma at many centers despite limited evidence of benefit.^20–22 In fact, even some early studies hinted that heavier anticoagulation might do more harm than good. For example, a 1995 review of 517 free flaps found that high-dose heparin infusions were associated with an approximately 20% hematoma rate (versus ~5% with no anticoagulation), without any statistically significant improvement in flap survival.²³

More recent comparative studies and meta-analyses have confirmed that routine therapeutic-level anticoagulation does not improve free flap success rates and may instead introduce harm. A 2022 comprehensive meta-analysis of patients undergoing head and neck free flap surgery found no significant reduction in microvascular thrombosis or flap failures in those who received postoperative systemic anticoagulants (heparin drips, warfarin, high-dose enoxaparin, etc.) compared with those who received only standard prophylaxis.²⁴ Flap survival outcomes were statistically equivalent regardless of adding intensive anticoagulation.²¹ On the contrary, the patients receiving anticoagulation experienced substantially more bleeding issues. Furthermore, there was a nearly 3-fold increase in hematomas and bleeding complications requiring intervention among patients given additional systemic anticoagulation.²⁴ Similarly, a 2018 systematic review (analyzing >2000 head and neck free flaps) concluded that postoperative anticoagulation “barely decreases” the risk of flap loss or thrombosis, yet it significantly increases the risk of hematoma formation (approximately double the risk of hematoma compared with no anticoagulation, P = 0.03).²¹ In sum, more aggressive anticoagulation has not proven to yield better anastomotic patency, but it clearly raises the risk of bleeding-related complications.

Low-molecular-weight dextran, an antithrombotic plasma expander, was once popular in free flap protocols, but evidence showed it provided no outcome benefit and carried significant risks. Studies in the 1980s–2000s demonstrated that dextran did not meaningfully improve microvascular patency or flap survival, whereas it significantly increased systemic complications. A prospective trial of 100 patients undergoing head and neck free flap reconstruction at Memorial Sloan Kettering Cancer Center compared postoperative prophylaxis with dextran versus aspirin; the flap outcomes were the same across groups, yet the incidence of serious complications in the dextran-treated patients was strikingly high.²⁰ Notably, dextran has been linked to adverse reactions such as anaphylactoid responses, adult respiratory distress syndrome, cardiac overload, hemorrhage, and renal failure.²⁵ Therefore, the routine use of dextran in microsurgery has been largely abandoned.

Regarding aspirin, multiple studies have found no clear difference in free flap thrombosis or success rates with versus without aspirin in elective microsurgery. For instance, a 2013 retrospective study of 390 microvascular free flaps showed that flap failure rates were statistically unchanged by the use of aspirin prophylaxis; the flap survival was 97%–98% in both aspirin-treated and non–aspirin-treated groups.²⁶ In that series, using aspirin did not reduce bleeding or flap loss rates, and in fact, the aspirin group had a slightly higher overall complication rate (38% versus 27%) and more take-back procedures compared with the control group, which received neither aspirin nor other anticoagulants.

Importantly, standard DVT prophylaxis is still recommended for all free flap patients as part of perioperative management. Free flap patients (often cancer or trauma patients undergoing long operations) are at risk for venous thromboembolism; thus, prophylactic measures such as subcutaneous heparin or enoxaparin and pneumatic compression devices are routinely applied to mitigate against DVT and pulmonary embolism.²⁷ This basic venous thromboembolism (VTE) chemo- and mechano-prophylaxis is distinct from the idea of improving the flap’s microvascular patency. The key is that escalating beyond prophylactic doses (ie, using full therapeutic anticoagulation or multiagent regimens in every case) in an attempt to improve the flap’s own patency is not supported by evidence.²⁸ Contemporary best practice is to provide VTE chemoprophylaxis for all patients and reserve any therapeutic-intensity anticoagulation for specific high-risk scenarios.²⁹

Recommendation

The use of therapeutic-level anticoagulation should be avoided for routine flap protection. Dextran use is unsafe. Standard DVT prophylaxis is sufficient for flap protection, if needed (Evidence Level—Moderate; Strength of Recommendation—A).

HIGH-DOSE STEROIDS USE

In reconstructive microsurgery, it was believed that administering high-dose perioperative steroids (eg, intravenous dexamethasone or methylprednisolone) could limit ischemia-reperfusion injury to the flap and decrease postoperative swelling, thereby improving flap perfusion and overall outcomes. Early support for this idea came from animal studies suggesting that steroids might mitigate reperfusion.^30,31

Despite the plausible rationale, clinical evidence does not support routine high-dose steroid use for free flaps (and some studies indicate it may be detrimental). A large 2025 retrospective study of 711 head and neck free flap cases found that patients who received high-dose perioperative steroids had significantly higher complication rates than those who did not (53.1% versus 20.1%, P < 0.0001).³² Steroid use was associated with more than a 4-fold increase in flap-related complications, including a higher incidence of partial flap necrosis, venous congestion or crisis, and flap infections, as well as more wound healing problems.

In conclusion, routine steroid use in free flap surgery is not evidence-based and may be harmful. Current practice trends discourage high-dose steroids for edema control, emphasizing that their risks (poor wound healing, infection, hyperglycemia) outweigh any theoretical benefit.

Recommendation

Perioperative high-dose steroid use may be associated with a high risk of flap complications (Evidence Level—Low–Moderate; Strength of Recommendation—C).

PROLONGED ANTIBIOTICS USE

In microsurgical free flap reconstructions (especially head and neck), many surgeons have traditionally given prophylactic antibiotics for 5–7 days or until drains are removed, fearing that communication with oral or enteric flora will cause surgical site infections (SSIs). However, standard guidelines do not support this. In fact, the Centers for Disease Control and Prevention and other surgical guidelines recommend stopping prophylactic antibiotics within 24 hours (or at wound closure) for clean or clean-contaminated cases.³³

In head and neck free flap surgery, a 2003 prospective trial of 74 patients reported no difference in infection rates between short-course (3 doses) and long-course (15 doses) clindamycin prophylaxis.³⁴ A 2016 multicenter cohort of 147 head and neck flaps found that extended antibiotics (>2 d) did not lower SSI compared with regimens of 2 days or less; in fact, longer courses were linked to higher pneumonia rates.³⁵ Even for clean free flaps (such as autologous breast reconstruction), a 2023 systematic review (3 studies, ~1400 patients) showed no significant difference in SSI rates whether antibiotics were continued beyond 24 hours or not (SSI rate for ≤24 h versus >24 h: 6.6% versus 8.1%; P = 0.124).³⁶

Together, these findings consistently show no added infection prevention from extended antibiotic prophylaxis. By contrast, prolonged antibiotic use can alter patient flora and drive resistant organisms or Clostridioides difficile infections.³³ Thus, best practice protocols advise limiting prophylaxis to 24 hours after incision closure, even in complex free flap cases.³⁷

Recommendation

Administration of perioperative antibiotics beyond 24 hours following microvascular reconstruction does not confer added benefits (Evidence Level—Moderate; Strength of Recommendation—A).

NEGATIVE-PRESSURE WOUND THERAPY USE

Traditionally, surgeons were wary of placing negative-pressure wound therapy (NPWT) directly on a free flap for fear that the suction might collapse its tiny vessels, compress the pedicle, or hinder monitoring.³⁸ Early anecdotal cases of flap congestion or loss under NPWT dressings led many to believe it was contraindicated in microsurgical flaps.

Recent perfusion studies have shown that subatmospheric dressings actually increase microvascular flow, instead of diminishing it.³⁸ In 1 study of free latissimus dorsi muscle flaps, continuous laser Doppler monitoring found significantly higher blood flow values at 12 hours postoperatively in the NPWT group compared with controls.³⁸ Modern clinical series echo these laboratory findings. Published reports consistently find no increase in flap failure when NPWT is used properly. In a comparative cohort of 54 free or perforator flaps (27 managed with NPWT, 27 with standard dressings), flap survival was statistically identical between groups (P = 0.91).³⁹ In practice, many centers now use NPWT on muscle and fasciocutaneous flaps (especially in the leg or heavily exudative wounds) without increased complications.⁴⁰ Several authors have also noted that NPWT effectively resolves early venous congestion in flaps and grafts, improving overall outcomes.⁴¹

Recommendation

NPWT use is safe in properly inset flaps (Evidence Level—Moderate; Strength of Recommendation—B).

FLAP MONITORING

Traditional practice held that free flaps required vigilant hourly checks for 5–7 days postoperatively to observe for early vascular compromise. For example, Kroll et al⁴² reported monitoring flaps hourly for 72 hours, then every 2–4 hours up to 7 days. This “week-long” intensive care unit (ICU) stay became dogma under the assumption that a flap needs constant surveillance until it is “out of the woods.” This approach was time- and resource-intensive but thought necessary to maximize success rates.

More recent studies strongly support intensive monitoring only for the first few days. In multiple series, more than 80%–96% of vascular compromises (arterial or venous thromboses) were detected within the first 48–72 hours. For instance, Chen et al⁴³ found that 82.3% of compromised flaps presented within 24 hours and 95.6% within 72 hours. Similarly, Kroll et al⁴² reported that 80% of flap problems arose in the first 2 days and only approximately 5% after postoperative day 3. Consistently, modern data show that flap salvage success plummets after the early period; the systematic review by Shen et al⁴⁴ reported salvage rates of 93.8% in 24 hours, 83.3% by day 2, 12.1% on day 3, and 0% thereafter. In 1 high-volume DIEP flap series using continuous monitoring, all microvascular take-backs happened within 23 hours (flap failure rate only 0.66%).⁴⁵ Likewise, Cornejo et al⁴⁶ emphasized that most thrombotic events occur in the first 24–48 hours, leading them to recommend monitoring every 1–2 hours for the first 72 hours. When late thromboses occur, they are usually detected too late for salvage. In fact, 1 analysis found no successful salvages for events occurring after the third postoperative day.⁴²

Multiple studies find that de-escalating monitoring after 2–3 days is safe. A 2021 meta-analysis showed no increase in flap failure or complications when stable patients were managed on the ward.⁴⁷ A 2024 quality-improvement study similarly found that shifting patients undergoing head and neck flap reconstruction to a general ward (with less-frequent checks) did not raise the flap loss rate (2.9% pre versus 2.6% post, P > 0.9) and actually shortened ICU stays.⁴⁸ Fracol et al⁴⁹ also reported 188 DIEP flaps with a 99.5% success rate despite discharging most patients by postoperative day 2. Likewise, Hanick et al⁵⁰ found that carefully selected patients undergoing head and neck free flap reconstruction discharged by day 3 had no increase in flap failures or readmissions.

Consensus is that intense monitoring beyond 2–3 days is generally unnecessary. Guidelines explicitly defining a 5- to 7-day protocol do not exist, and practices are largely institution- or surgeon-dependent. Authors agree that intensive surveillance (often ICU level) is vital in the first 48–72 hours. Importantly, the evidence base is low level (mostly retrospective cohorts and reviews). No randomized controlled trials compare hourly versus less-frequent monitoring schedules. In other words, no level I evidence dictates the optimal duration or interval. Thus, current “guidelines” reflect expert consensus: essentially grade C recommendations drawn from observational data.

Recommendation

ICU-level monitoring of flaps beyond 72 hours may not be associated with any added benefit (Evidence Level—Moderate; Strength of Recommendation—C).

CERTAIN PATIENTS (older, DIABETIC, OBESE, OR IMMUNOCOMPROMISED) ARE NOT CANDIDATES FOR MICROSURGERY

Historically, surgeons often avoided free flap reconstruction in older, diabetic, obese, or immunocompromised patients due to concerns about fragile vessels, poor healing, microvascular disease, and wound problems.⁵¹ An increasing number of patients requiring reconstructive microsurgery are immunocompromised due to organ transplants, autoimmune diseases, hematologic malignancies, or long-term immunosuppressive therapies. Improved survival after solid organ transplantation (eg, ~70% 10-y survival for liver recipients) means that more such patients now present for elective reconstruction, making it crucial for microsurgeons to understand and manage the associated risks.⁵²

In practice, alternative, simpler procedures (pedicled flaps or skin grafts) were offered instead of free tissue transfer. However, numerous contemporary studies have debunked this cautionary approach. Large reviews and meta-analyses consistently show that age, diabetes, or obesity alone do not significantly increase free flap failure rates when patients are otherwise optimized.^53,54

A 2017 meta-analysis of more than 1000 free flaps in patients 70 years or older found no significant difference in flap survival compared with younger cohorts (flap loss rates were statistically equivalent).⁵³ In fact, free flap survival rates in older patients are typically in the mid-90% range, comparable to overall rates. Even in a study of 838 flaps among octogenarians (47 patients ≥80 y), the “very old” group had a similar flap failure rate compared with younger patients (8.5% versus 5.4%, respectively; P = 0.328).⁵⁵ Similarly, large database studies have found no increase in flap failure attributable to diabetes when compared with patients without diabetes.⁵⁶ In a 2019 review of more than 6000 free flap cases, diabetes was not associated with higher rates of flap loss.⁵⁶ Patients with diabetes did have more wound complications (eg, SSIs, dehiscence) and slightly longer hospital stays; however, with good perioperative glucose control and close monitoring, the vast majority of flaps survived.⁵⁶

Shin et al⁵⁴ reported that outside of breast reconstruction, obese patients have essentially the same free flap survival as nonobese patients. Consistently, pooled data show no significant difference in partial flap loss, total flap loss, or overall complications for obese versus normal-weight patients undergoing head and neck or extremity free flaps.

Early reports cautioned that immunosuppressed patients have higher risks of wound complications and adrenal crises, but also demonstrated that major reconstructive procedures can succeed with meticulous care.⁵⁷ A 2008 multicenter series of 19 organ‐transplant patients requiring free flaps found no flap losses and infrequent delayed healing, concluding that free tissue transfer can be safely performed in well-selected immunosuppressed patients.⁵⁸ Similarly, other studies have reported high flap success rates: a series of 28 head-and-neck free flaps in transplant recipients had a 0% flap failure with careful multidisciplinary management, and a cohort of 17 transplant patients in China had no flap complications.^59,60

However, immunosuppression does correlate with a higher overall incidence of wound and surgical complications.^52,61 Nonetheless, nearly all wounds ultimately heal with an appropriate, disciplined multidisciplinary approach, including optimized timing, adequate infection prophylaxis, and meticulous technique.⁶²

In summary, instead of excluding these groups of patients, surgeons now focus on perioperative optimization (eg, stabilizing glucose, improving nutrition, ensuring adequate infection prophylaxis, optimizing perioperative cardiovascular status, and titrating immunosuppressive agents) and proceed with indicated free flaps if the benefits outweigh the risks.^57,59 It is very important, however, to acknowledge a potential selection bias in the available published reports, as even within these groups of patients, those with relatively lower cumulative comorbidity burden may be preferentially selected for microsurgical reconstructions.

Recommendation

Older age, obesity, diabetes, solid organ transplantation, or other forms of immunosuppression are not contraindications to microvascular reconstructions (Evidence Level—Moderate; Strength of Recommendation—B).

The summary of all evidence is presented in Table 2.

Table 2.

Evidence Summary

Myth/Practice	Recommendation (A–D)*	GRADE Certainty†
Intraoperative vasopressors harm free flaps	B: Judicious vasopressors are safe and guideline-concordant for BP targets	Moderate (consistent cohorts + meta-analyses; mostly observational)
NSAIDs cause hematoma or thrombosis	B: Incorporate NSAIDs/COX-2 to enable opioid-sparing without higher flap loss/hematoma	Moderate (multiple procedure types; consistent effect)
Routine therapeutic anticoagulation (and dextran) improves patency	A: Avoid therapeutic-intensity anticoagulation/dextran routinely; provide standard VTE prophylaxis only	Moderate (consistent lack of benefit; bleeding risk ↑; 1 RCT for dextran)
High-dose perioperative steroids improve outcomes	C: Do not use routinely; potential harms outweigh theoretical benefits	Low–moderate (limited clinical data; signal of harm)
Prolonged postoperative antibiotics reduce SSI	A: Limit prophylaxis to ≤24 h in clean/clean-contaminated cases	Moderate (1 RCT + concordant studies/guidelines)
NPWT is unsafe on free flaps	B: NPWT is acceptable on properly inset flaps with appropriate settings	Moderate (physiology + concordant clinical series)
Flaps require 5–7 d of ICU-level hourly monitoring	B: Focus intensive checks in the first 48–72 h; step down thereafter in stable patients	Moderate (strong temporal signal; observational + meta-analytic)
Older/diabetic/obese are poor microsurgical candidates	B, Do not exclude solely on age/diabetes/obesity; optimize risks and proceed	Moderate (large datasets; consistent)

^*Recommendation grades (A–D): A, strong recommendation (clear benefit/harms balance, consistent evidence or authoritative guideline); B, moderate recommendation (benefits outweigh harms with consistent evidence, often observational or mixed); C, conditional/weak (context-dependent, heterogeneity or limited data); D, insufficient evidence/expert opinion only.

^†GRADE approach: Randomized trials and high-quality meta-analyses start as high; observational studies start as low and may be upgraded for consistency, size, or dose-response; ratings may be downgraded for bias, imprecision, or heterogeneity. Final grades reflect aggregate certainty supporting the stated conclusions.

BP, blood pressure; RCT, randomized controlled trials.

CONCLUSIONS

In summary, our practical review of 8 long-standing perioperative practices in reconstructive microsurgery reveals that many are unsupported by high-quality evidence and should be reconsidered in modern clinical protocols. Adoption of these updated practices promotes standardized care, reduces unnecessary interventions, and optimizes outcomes for patients undergoing microsurgical reconstruction.

DISCLOSURES

Dr. Janis receives royalties from Thieme Medical Publishers and Springer Publishing. The other authors have no financial interest to declare in relation to the content of this article.