Factors affecting wound healing after major amputation for vascular disease: a review

Indocyanine green dye and its application in gastrointestinal surgery: The future is bright green

Indocyanine green (ICG) is a water-soluble fluorescent dye that is minimally toxic and widely used in gastrointestinal surgery. ICG facilitates anatomical identification of structures (e.g., ureters), assessment of lymph nodes, biliary mapping, organ perfusion and anastomosis assessment, and aids in determining the adequacy of oncological margins. In addition, ICG can be conjugated to artificially created antibodies for tumour markers, such as carcinoembryonic antigen for colorectal, breast, lung, and gastric cancer, prostate-specific antigen for prostate cancer, and cancer antigen 125 for ovarian cancer. Although ICG has shown promising results, the optimization of patient factors, dye factors, equipment, and the method of assessing fluorescence intensity could further enhance its utility. This review summarizes the clinical application of ICG in gastrointestinal surgery and discusses the emergence of novel dyes such as ZW-800 and VM678 that have demonstrated appropriate pharmacokinetic properties and improved target-to-background ratios in animal studies. With the emergence of robotic technology and the increasing reporting of ICG utility, a comprehensive review of clinical application of ICG in gastrointestinal surgery is timely and this review serves that aim.

Measuring discomfort-An objective method for quantifying peak pressure discomfort and improved fit in adults with transtibial amputation

BACKGROUND

Prosthetic socket coupling with the residual limb should be comfortable without causing skin breakdown or excessive pressure. However, users report socket discomfort, and there is a scarcity of objective measurements available to assess this feeling of discomfort. Quantifying the specific pressure may enable clinicians and users to determine and improve comfort levels objectively.

OBJECTIVES

(1) To evaluate if a peak pressure reduction assists in resolving wounds, redness, and pain inside prosthetic sockets in people with transtibial amputation. (2) To determine if peak pressures measured inside the prosthetic socket due to external forces could be used to quantify the level of improvement in socket discomfort.

DESIGN

In this cohort study, we used a pressure sensor to quantify and facilitate adjustments to the prosthetic socket, correlating this information to the user's socket comfort.

SETTING

Outpatient clinic in a tertiary hospital in Singapore.

PARTICIPANTS

People (N = 16) with unilateral transtibial lower limb amputation using a prosthesis.

INTERVENTIONS

NA.

MAIN OUTCOME MEASURES

Peak pressure and socket comfort score (SCS).

RESULTS

The peak pressure value showed a statistically significant reduction across all participants following adjustments at a 50% delta change in pressure (p = .001). This was achieved with a mean number of 2.6 ± 1.4 adjustments per participant. Following the adjustments, the paired t-test results showed a mean increase between the first SCS and final SCS was 2.6 (p = .001).

CONCLUSION

The wound, redness, and pain resolved in 15 of 16 participants regardless of diabetic status following socket adjustments. Although the peak pressures values did not correlate to the SCS score, the reduction in peak pressure saw significant improvement to the SCS. The use of a portable sensor is a fast and efficient means to quantify adjustments inside the prosthetic socket and could potentially be considered as part of future care delivery.

Classification and Production of Polymeric Foams among the Systems for Wound Treatment

This work represents an overview on types of wounds according to their definition, classification and dressing treatments. Natural and synthetic polymeric wound dressings types have been analyzed, providing a historical overview, from ancient to modern times. Currently, there is a wide choice of materials for the treatment of wounds, such as hydrocolloids, polyurethane and alginate patches, wafers, hydrogels and semi-permeable film dressings. These systems are often loaded with drugs such as antibiotics for the simultaneous delivery of drugs to prevent or cure infections caused by the exposition of blood vessel to open air. Among the presented techniques, a focus on foams has been provided, describing the most diffused branded products and their chemical, physical, biological and mechanical properties. Conventional and high-pressure methods for the production of foams for wound dressing are also analyzed in this work, with a proposed comparison in terms of process steps, efficiency and removal of solvent residue. Case studies, in vivo tests and models have been reported to identify the real applications of the produced foams.

Tibial bypass in patients with intermittent claudication is associated with poor outcomes

OBJECTIVE

Given that intermittent claudication (IC) rarely progresses to chronic limb-threatening ischemia and limb loss, safety and durability of elective interventions for IC are essential. Whether patients with IC benefit from tibial intervention is controversial, and data supporting its utility are limited. Despite endovascular therapy expansion, surgical bypass is still commonly performed. We sought to assess outcomes of bypass to tibial arteries for IC.

METHODS

The Vascular Quality Initiative (2003-2018) was queried for infrainguinal bypasses performed for IC. Perioperative and 1-year outcomes were compared between bypasses constructed to tibial and popliteal arteries.

RESULTS

Of 5347 infrainguinal bypasses, 1173 (22%) and 4184 (78%) were tibial and popliteal bypasses, respectively. Overall, mean age was 65 ± 10 years, and patients were often men (72%) and current smokers (42%). Tibial bypasses commonly targeted posterior tibial (40%), tibioperoneal trunk (23%), and anterior tibial (19%) arteries. Great saphenous vein was more often used for tibial bypass than for popliteal bypass (78% vs 54%; P < .001). Patients undergoing tibial compared with popliteal bypass more often had impaired ambulation and prior ipsilateral bypasses and were less often taking antiplatelets and statins (all P < .05). In the perioperative period, tibial bypass patients had longer postoperative length of stay (4.5 ± 3.5 vs 3.5 ± 2.8 days), more pulmonary complications (1.3% vs 0.6%), and higher return to the operating room (7% vs 4%; all P < .05). Perioperative myocardial infarction (1.2% vs 0.8%; P = .19), stroke (0.4% vs 0.4%; P = .91), and mortality (0.3 vs 0.3%; P = .86) rates were similar between the cohorts. At 1 year, tibial compared with popliteal bypasses exhibited lower freedom from occlusion/death (81% vs 89%; P < .001), ipsilateral major amputation/death (90% vs 94%; P < .001), and reintervention/amputation/death (73% vs 80%; P < .001), but patient survival was similar (96% vs 97%; P = .07). On multivariable analysis, tibial compared with popliteal bypass was independently associated with increased occlusion/death (hazard ratio [HR], 1.65; 95% confidence interval [CI], 1.28-2.11; P < .001), major ipsilateral amputation/death (HR, 1.6; 95% CI, 1.12-2.19; P = .003), and ipsilateral reintervention/amputation/death (HR, 1.51; 95% CI, 1.28-1.79; P < .001), with similar patient survival.

CONCLUSIONS

In patients with IC, tibial bypass was associated with poor outcomes, including major amputation. Surgeons should exhaust nonoperative therapies and present realistic outcome expectations to their patients before offering such intervention.

Prediction of stump healing in lower limb amputation: a narrative review

Both types of diabetes, as well as different forms of acquired diabetes, are associated with diabetic peripheral neuropathy. Diabetic foot ulcers (DFU) is the condition most commonly related to somatic peripheral neuropathy, often leading to gangrene and limb amputation. Independent from large-vessel disease, sensory loss may result in DFU development and even amputation. The crucial part of any lower limb amputation is the stump healing process, which represents the central goal of postoperative management. Despite the importance attributed to this process, a standard set of guidelines regarding efficient healing methods is yet to be formulated. Health professionals are faced with the challenge of assessing the different risk factors and deciding which has a greater influence on the stump healing rate. There is currently an insufficient number of studies regarding factors effecting lower limb amputation. The main purpose of this review is to discuss the markers that can be helpful in the prediction of stump healing in patients who have undergone lower limb amputation.

Outcomes of knee disarticulation and the influence of surgical techniques in dysvascular patients: A systematic review

BACKGROUND

Dysvascularity is the main cause of lower limb amputations in Scotland, and there is an insignificant proportion (1.7%) of knee disarticulations, despite the benefits of amputation.

OBJECTIVES

The outcomes of knee disarticulation and its associated surgical techniques will be evaluated based on healing, reamputations, functional outcomes, prosthetic ambulation and gait biomechanics to determine whether a greater rate of knee disarticulations can be justified among dysvascular patients.

STUDY DESIGN

Systematic review.

METHODS

Key electronic databases were searched for the relevant literature based on a pre-specified eligibility criterion.

RESULTS

The 17 articles included in this review were appraised for their quality, and key findings are extracted.

CONCLUSION

Healing rates are favourable, but there is a need for appropriate amputation level selection to prevent reamputations. Knee disarticulation patients have better maintenance of independent living status than transfemoral patients, but overall prosthetic ambulation rates are inconsistent. In terms of gait biomechanics of knee disarticulation, there are some positive indications, but the evidence is insubstantial. A stronger body of evidence is required in this subject field, and recommendations are made for future research - Scottish Intercollegiate Guidelines Network Grade of Recommendation: C.

CLINICAL RELEVANCE

This review aims to inform the multidisciplinary teams involved in the rehabilitation of dysvascular amputees about evidence-based outcomes following knee disarticulation. This knowledge will be beneficial when formulating treatment pathways for this vulnerable population group.

Effects of early mobilization on unhealed dysvascular transtibial amputation stumps: a clinical trial

OBJECTIVE

To observe the effects of early mobilization on unhealed transtibial (TT) amputation stump wounds of dysvascular etiology. An "unhealed" stump was defined as having a wound greater than 1cm x 1cm at least 3 weeks after surgery.

DESIGN

An observational cohort study.

SETTING

This center receives about 250 new lower-limb amputees a year from over 50 surgeons working in 16 hospitals. Over 35% are unhealed.

PARTICIPANTS

Sixty-six consecutive new TT amputees (age 62.8+/-10.8y) of dysvascular etiology (diabetes 50%) with unhealed stumps were recruited. Sixty-one percent were current or past smokers. The mean +/- SD stump wound size was 7.7+/-2.7cm x 3.2+/-2.0cm.

INTERVENTIONS

The wound size was measured, and stump transcutaneous oxygen (TcpO(2)) and transcutaneous carbon dioxide (TcpCO(2)) were measured. Wounds were debrided and dressed by using a standard protocol. Mobilization using a Pneumatic Post-Amputation Mobility (PPAM) Aid for approximately 3 weeks was followed by provision of a TT prosthesis. A standard physiotherapy walking training program was performed.

MAIN OUTCOME MEASURES

Stump wound healing, time to achieve healing, and resting transcutaneous oxygen pressure pre- and posttherapy.

RESULTS

Of the 66 amputees, 4 did not start. Sixty-two started; 6 withdrew, and 56 completed the trial. Complete wound healing was achieved in 74% (46/62) over a mean of 141 (87-270) days. The mean +/- SD stump TcpO(2) at baseline was 41.3+/-19.8mmHg and increased significantly to 50.6+/-21.9mmHg (P<.02) after 97 (34-185) days of mobilization. Nine of 46 required revision plastic surgery. Five subjects, whose wounds were healing, became unwell, dropped out, and later deceased. Five subjects, all current smokers, did not heal and underwent higher amputation.

CONCLUSIONS

Patients with large unhealed TT stump wounds can simultaneously undergo walking training by using a prosthesis and can achieve wound healing. Seventy-four percent of subjects achieved full wound healing. The small minority of patients who did not heal were current smokers whose TcpO(2) levels did not improve throughout the trial. Rising levels of stump TcpO(2)were associated with wound healing.

An Analysis of Risk Factors Associated with Failure of Below Knee Amputations

BACKGROUND

Below knee amputation (BKA) is often required in patients with critical limb ischemia. When such a procedure fails, an above knee revision (AKA) is required. This can cause further complications in this group of patients, who already have a high incidence of medical co-morbidities.

METHODS

Case records of 47 patients (51 procedures performed) with BKA for peripheral vascular diseases during a 4-year period were reviewed. Clinical factors were analyzed using bi- and multi-variate analysis against the procedure outcome. Degree of social deprivation was evaluated with DEPCAT score in relation to amputation failure. Each arterial segment of the pre-operative arteriograms was scored based on a 3-point scoring system (0=normal, 1=stenosis, and 2=cclusion). With the assignment of an arbitrary weight for each segment, a total arterial score (TAS) was derived for each patient.

RESULTS

Eighteen percent of BKA (n=9) failed. Absence of popliteal pulse (failure vs. success: 100% vs. 63%, P=0.04), calf rest pain (67% vs. 20%, P=0.01), combination of calf rest pain and feet tissue loss (CRPFTL; 67% vs. 3%, P=0.00), postoperative stump trauma (44% vs. 10%, P=0.03), and wound infection (WI; 89% vs. 26%, P=0.00) were factors associated with the failure of a BKA in bivariate analysis. Using multiple logistic regression, WI (OR=14) and CRPFTL (OR=47) were found to be independent predictors for the outcome of BKA. No statistical significance was found between the DEPCAT score and the failure rate. TAS was significantly higher in the failure group (median=17 vs. 9; P=0.00).

CONCLUSIONS

This study suggests that CRPFTL and postoperative WI are predictor variables for the failure of a BKA. In addition, there is the potential role of arteriogram scoring in predicting the outcome of a BKA.

Stump management after trans-tibial amputation: a systematic review

In order to achieve stump healing after trans-tibial amputation, various methods are applied, such as soft dressings followed by elastic wrapping of the stump, rigid dressings, semi-rigid dressings, and more recently the application of silicon or gel-liners. A systematic literature search was performed to identify the optimal post-amputation management. The methodological quality of the studies was systematically evaluated by using a predefined list of criteria. Only 11 controlled studies were identified and evaluated for their methodological quality. From these studies, no studies were classified as A-level studies, whereas three were classified as B-level, and 8 were classified as C-level studies. Relevant literature appears heterogeneous with respect to patient selection, intervention and outcome measures. Despite the large variability of included studies, this review reveals a trend in favour of rigid and semi-rigid dressings for achieving stump healing and reduction of stump volume. No conclusions can be drawn with regard to the effect on functional outcome. The literature is not conclusive on the effects of early weight bearing on stump healing, volume reduction, and functional outcome. More research is needed for the development of evidence-based clinical practice guidelines concerning management after transtibial amputation.

Management of soft tissue deficiency of the hallux: salvage in trauma, diabetes, and following surgical complications

Loss of the hallux can lead to significant gait problems and cause difficult biomechanical problems with weight bearing. Amputation of the first ray should be avoided when possible. Soft tissue defect of the hallux can be particularly difficult to manage because of the absence of local muscle tissue for coverage. In younger patients, soft tissue loss usually is related to trauma; an understanding of the techniques that are available for coverage are important to maintain length and function of the first ray. Diabetic neuropathy and resultant ulceration of the hallux or metatarsophalangeal joint is another common cause of soft tissue deficiency that may lead to deep infection and potentially result in amputation. Certain systemic problems, such as inflammatory diseases or gout, can cause significant degeneration of the local tissues which also can be problematic. Wound dehiscence or loss of skin flaps that are created during surgery represent further difficulties that may be encountered. This article reviews the common causes of amputation of the hallux and the principles that are necessary for salvage of the digit.