Dorsal Metatarsal Artery Research Articles

Accuracy of Indirect Measurement of Blood Pressure in Neonatal Foals

The objectives of this study were to assess, in anesthetized neonatal foals, the accuracy of 2 automated indirect oscillometric monitors for measurement of mean arterial pressure (MAP), to determine the optimal site of cuff placement for MAP monitoring, and to determine the relationship between arterial blood pressure and cardiac output. Ten neonatal foals were anesthetized and instrumented with a catheter in the metatarsal artery for direct MAP monitoring and measurement of cardiac output by lithium dilution. Concurrent MAP measurements were obtained with Cardell and Dinamap oscillometric monitors with cuffs placed at 3 different sites (coccygeal, metatarsal, and median arteries). Blood pressure was manipulated by varying the depth of anesthesia and by administration of dobutamine or phenylephrine. A statistically significant (P = .025) interaction was found between the type of monitor and cuff placement site. With the Cardell monitor, placement of the cuff over the coccygeal artery resulted in a significantly lower bias than placement over the median or dorsal metatarsal artery (P < .0001 and P = .0149, respectively). No significant difference in bias was found with cuff placement site when using the Dinamap monitor. The correlation coefficient (r) between MAP and cardiac output was 0.47. Indirect oscillometry with a cuff placed over the coccygeal artery or dorsal metatarsal artery is an acceptable method for measuring MAP in foals. Blood pressure does not correlate well with cardiac output in anesthetized foals.

Isolated Third-Toe Transfer: Indications, Technique, and Reliability

Isolated third-toe transfer is a versatile and safe technique when indicated. Between January of 1984 and January of 2003, 37 isolated third-toe transfers were performed in 31 patients. Only one partial loss was noted among 37 transfers. There were 24 male and seven female patients, with an average age of 27.4 years (range, 7 to 43 years). Twenty-five patients received additional toe transfers. Secondary surgery was performed in 17 toes of 15 patients to improve the functional and cosmetic results. Patients were followed for 2 to 180 months (average, 36 months) and no significant donor-site morbidity was seen. Basically, the indications for isolated third-toe transfer are evaluated in two groups. Third-toe transfer is absolutely indicated when it is necessary for restoring basic hand functions in multiple-finger amputations. It is indicated because both second toes are transferred or the remaining second toe is adjacent to the previously transferred great toe. The other absolute indication is the unavailability of second toes because of trauma or deformity. Third-toe transfer is indicated relatively if it is used for additional reconstruction when basic hand functions are regained or already exist. Another relative indication is its better size match for proposed reconstruction. Second and third dorsal and plantar metatarsal arteries can be used as the pedicle artery for third toe-transfer; however, if second-toe transfer has already been performed or is planned, the third plantar or dorsal metatarsal artery should be used. Isolated third-toe transfer is a useful and reliable technique, especially in multiple-finger amputation reconstruction.

Destructive Lesions of the Proximal Sesamoid Bones as a Complication of Dorsal Metatarsal Artery Catheterization in Three Horses

To describe focal destructive lesions of the proximal sesamoid bones (PSBs) as a complication of dorsal metatarsal artery catheterization performed for direct blood pressure monitoring during equine general anesthesia. Retrospective study. Three client-owned horses. A dorsal metatarsal artery was catheterized in each of 3 horses for direct blood pressure monitoring during anesthesia. Radiography, ultrasonography, synoviocentesis, and arthroscopy were used to diagnose postoperative lameness that occurred in the limb used for blood pressure monitoring. Horses developed severe lameness, localized to the fetlock region of the catheterized limb within 21 days of surgery. Antibiotic therapy was administered. Surgical debridement was possible in 1 horse. Two horses that had lesions that were inaccessible, failed to respond to medical management and were euthanatized. The 3rd horse that had surgical debridement of affected bone, survived. Changes in hospital protocol, by improving aseptic technique during catheter insertion and use of new manometer tubing and heparinized saline for each arterial catheter inserted in the dorsal metatarsal artery, have eliminated this complication. Diagnosis and treatment of destructive lesions of the PSB were difficult. Strict aseptic technique should be followed during insertion of arterial catheters. Focal destructive lesions of the PSB subsequent to dorsal metatarsal arterial catheterization is a rare but serious complication of equine anesthesia.

Salvage of free second toe with venous thrombosis by shunting retrograde arterial flow of second dorsal metatarsal artery

Although there are case reports about salvaging amputated digits without venous return by shunting retrograde blood flow from a distal digital artery to a proximal vein (Smith et al., Plast Reconstr Surg 71:52, 1983), successful salvage of a congested free toe with efferent arteriovenous (AV) shunting retrograde arterial flow from the second dorsal metatarsal artery (SDMA) has never been reported. In this paper, we describe the possible factors for venous thrombosis, the errors we committed in the operation, and how the free toe can survive without venous drainage.

Distally based first web flap for coverage reconstruction of the great toe

Resurfacing the distal part of the foot is still difficult. Distally based fascio-cutaneous first web flap has a sufficient arc of rotation to reach the toes. This flap is reverse-flow vascularised by the distal communicating artery, which is the distal connection between the plantar and the dorsal first metatarsal arteries. The authors describe its application for the coverage of a dorsal defect of the great toe.

Blood pressure and electrocardiographic effects of acepromazine in anaesthetized horses

Acepromazine, a phenothiazine tranquilizer, causes hypotension in standing horses (Parry et al. 1982). However, a retrospective study (Taylor & Young 1993) showed that acepromazine pre-anesthetic medication did not affect arterial blood pressure (MAP) in anaesthetized horses. This study examined the effects of acepromazine on MAP during romifidine–ketamine–halothane anaesthesia in horses anaesthetized for various surgical procedures. Forty-four horses were allocated by block randomization to groups A and B. Group A received acepromazine 0.05 mg kg−1 IM 30 minutes before induction of anaesthesia, group B did not. All horses received romifidine 0.1 mg kg−1 IV 5 minutes before anaesthesia was induced with diazepam 0.05 mg kg−1 and 2.2 mg kg−1 ketamine IV. The horses' trachea were intubated and horses breathed 50% oxygen and 50% nitrous oxide plus halothane (concentration adjusted as required clinically) from a circle breathing system. Nitrous oxide was discontinued after 10 minutes and analgesics, flunixin 1.1 mg kg−1 and either morphine 0.1 mg kg−1 or butorphanol 0.05 mg kg−1 (matched for horses undergoing the same procedure) administered IV. The facial or dorsal metatarsal artery was catheterized for direct measurement of MAP (every 10 min) and withdrawal of blood for gas analysis (every 30 min). The electrocardiogram (ECG) was monitored continuously with a 10 seconds printout obtained every 10 minutes. Intermittent positive pressure ventilation (IPPV) was instigated if PaCO2 exceeded 9.3 kPa (70 mm Hg). Dobutamine was infused (1.0–5.0 kg−1minute−1) if MAP 70 mm Hg. Mean age, weight and duration of anaesthesia were compared between the groups using a t-test for independent samples. Gender distribution and numbers of horses requiring IPPV or dobutamine were compared between groups using a chi-squared test (with Yates correction). To compare MAP over time, the area under the curve (MAPAUC) was calculated and compared between groups using a t-test. Horses receiving dobutamine were excluded from MAPAUC and MAP comparisons. The ECG printouts were examined for arrhythmias. There were no significant differences between groups (p > 0.05). Group A contained three stallions, 10 geldings and nine mares, aged 6.3 years (range 0.75–18). Group B comprised eight stallions, 11 geldings and three mares aged 7.3(1–16) years. Duration of anaesthesia was group A 97 (50–140) minutes, group B 99 (50–160) minutes. Eight horses in group A and three in group B required IPPV. Nine horses in group A and four in group B received dobutamine. Mean arterial pressure ranged from 60 to 128 mm Hg in group A and 58–96 mm Hg in group B. Mean MAPAUC was 5941 mm Hg minute−1 in group A, in B 6000 mm Hg minute−1. Atrial pre-mature complexes were recorded from one horse in group B. No other arrhythmias were detected. Although MAP was lower in the acepromazine group, this appeared unlikely to cause a clinical problem. The incidence of arrhythmias was too low to determine the influence of acepromazine in this study.

Reconstruction of Diabetic Foot Ulcers by Regional Flap Surgery

Purpose : The purpose of this study was to evaluate the value of regional flap surgery for diabetic foot ulcers combined with infection or bone and tendon exposure. Materials and Methods : We reviewed eight patients, nine cases of diabetic foot ulcers, which were treated by regional flap surgery. There were two Wagner’s grade 2 ulcers and six Wagner's grade 3 ulcers. We performed four reversed sural artery neurocutaneous flaps, two lateral supramalleolar flaps, two medial plantar artery flaps and one first dorsal metatarsal artery flap. Results : Seven of nine flaps completely survived after regional flap surgery. One partial and one complete flap necrosis occurred. One partially necrotized flap needed an additional skin graft. One completely necrotized flap needed free rectus abdominis myocutaneous flap surgery. There were two new ulcers, which were treated by free flap surgery. No patient needed amputation above the ankle joint. Conclusion : Satisfactory results were obtained by regional flap surgery for diabetic foot ulcers. Regional flap surgery is regarded as an effective treatment modality for diabetic foot ulcer combined with bone and tendon exposure with infection.

The arterial supply of the lesser metatarsal heads: a vascular injection study in human cadavers.

The possibility of avascular changes of the metatarsal heads following forefoot surgery has been previously documented. The aim of this study was to investigate the arterial supply of the lesser metatarsal heads with regard to osteotomies of these bones. We used epoxy resin injections and a modified Spalteholz technique in human cadaveric specimens to demonstrate the intraosseous and extraosseous blood supply of the lesser metatarsals. The metatarsal heads had two arterial sources: 1. The dorsal metatarsal arteries, which arose from the dorsalis pedis artery, and 2. The plantar metatarsal arteries, which are branches of the posterior tibial artery. These two vessels typically anastomosed at two sites about the metatarsal heads, forming a vascular ring and provided an extensive extraosseous arterial network around the metatarsal heads. Small arterial branches of this network run distally on the metatarsal cortex to enter the bone of the metatarsal head. The nutrient arteries traversed the cortex of the metaphysis close to the capsular and ligamentous insertions to provide multiple branches for the supply of the subchondral bone. Extensive capsular stripping during metatarsal head osteotomies results in damage to the medial and lateral head vessels.

Postoperative arterial blood gases in spay/castration dogs: a comparison of butorphanol versus hydromorphone

This study compared the frequency and severity of postoperative (postop) hypoxemia and hypercarbia in healthy dogs receiving butorphanol (BU) versus hydromorphone (HY). All dogs were admitted for neutering and proved normal on physical examination, CBC, creatinine, and preoperative (preop) arterial blood gas (ABG). Dogs received 0.02 mg kg−1 acepromazine and 0.01 mg kg−1 glycopyrrolate, with 0.4 mg kg−1 BU (BU dogs, n= 10) or 0.2 mg kg−1 HY (HY dogs, n = 10) IM preop. Despite BU and HY being equipotent on a per weight basis, they are not necessarily equianalgesic. Therefore, clinically accepted dosages of BU and HY were used. Anesthesia was induced with 2–4 mg kg−1 thiopental boluses IV to effect, and maintained with isoflurane (ISO) and O2. A catheter was placed in the dorsal metatarsal artery. The POET agent monitor with proximal endotracheal side-stream sampling measured end-tidal Fe′ISO and CO2. The Fe′ISO was targeted between 0.9 and 1.5% and the ETCO2 between 30 and 45 mm Hg using PPV or IPPV. An intraoperative (intraop) ABG was obtained during stage III anesthesia 10–30 minutes prior to extubation. The BU dogs received 0.4 mg kg−1 BU and HY dogs 0.1 mg kg−1 HY IM prior to extubation. Post-extubation, an ABG, HR, RR, temperature, pulse quality, MM color, CRT, and nonblinded pain/sedation scores were obtained by the primary investigator at 10 minutes, 30 minutes, 1, 2, 3, and 4 hours. Anesthesia time, age, and weight for BU dogs were 119 ± 36.3 minutes, 1.9 ± 2.7 years, and 24.1 ± 8.4 kg and for HY dogs 170 ± 64.7 minutes, 0.93 ± 0.77 years, and 21.5 ± 10.3 kg, respectively. Student's t-test was used for statistical analysis on normally distributed data and the sign rank test on the A-a gradient data. Statistical significance was assigned for values of p < 0.05. Data are reported as mean ± SEM. In the HY dogs, PaCO2 was significantly higher compared to preop (preop PaCO2 = 36.9 ± 2.6 mm Hg) at 10 minutes, 30 minutes, 1, 2, and 3 hours (mean PaCO2 range = 41.0–44.3 mm Hg). No differences were found in PaCO2 of the BU dogs compared to preop. PaCO2 was significantly higher at 1 and 2 hours in the HY dogs (44.6 ± 3.1 and 42.8 ± 3.1 mm Hg, respectively) compared to the BU dogs (39.8 ± 4.2 and 39.4 ± 2.0 mm Hg, respectively). The PaO2 was significantly lower at 30 minutes compared to preop for the BU dogs (96.7 ± 7.6 mm Hg versus 100.2 ± 8.1 mm Hg) and at 1 hour compared to preop in the HY dogs (90.9 ± 10.4 mm Hg versus 101.4 ± 4.0 mm Hg). The A-a gradient was significantly higher at 30 minutes compared to preop for the BU dogs (9.5 ± 7.4 versus 5.5 ± 6.2). No differences in all other measured parameters were seen. Although HY caused more hypoventilation postop than BU and transient decreases in PaO2 occurred in both groups, mean PaCO2, PaO2, and A-a gradients remained clinically acceptable. The changes are statistically, but not clinically, significant. Future studies in compromised dogs should be performed.

THE ARTERIAL SYSTEM OF THE FIRST INTERMETATARSAL SPACE AND ITS INFLUENCE IN TOE-TO-HAND TRANSFER: A REPORT OF 53 LONG-PEDICLE TRANSFERS

A study of the arterial system in the first intermetatarsal space was performed during 53 toe-to-hand or vascularized tissue of the toe transfers with long arterial pedicles. The first dorsal metatarsal artery was used as a single pedicle in 25 transfers and the first plantar metatarsal artery in 21: both arteries were taken simultaneously in seven transfers. In 11 transfers, the dorsalis pedis artery and the perforating branch were absent, although this did not exclude the presence of a first dorsal metatarsal artery which arose from the plantar system by means of an ascending vascular branch in seven cases.

Origins of the dorsal metatarsal arteries in humans.

The foot is indispensable for man's daily activities and the integrity of its structure depends on its irrigation. The number of bypass operations for its arteries therefore increases as well as the use of vascularised flaps to cover defects in its dorsal region. To find out more details about the irrigation of the dorsum of foot, the formation of dorsal metatarsal arteries (DMA) was examined in 50 feet of 25 fixed cadavers of Brazilian adults of both sexes. The feet arteries were injected with neoprene latex dyed red, and then dissected. The first DMA originated from the dorsalis pedis artery in 86%, from the plantar network in 10% and the origin was mixed in 4%. The second DMA originated from the arcuate artery exclusively in 10%, the third DMA in 6%, and the fourth DMA in 10%. In its absence (48%), the lateral tarsal arteries and the proximal perforating branches were responsible for the formation of the second DMA in 52%, of the third DMA in 54%, and of the fourth DMA in 72%. The proximal perforating branches made an important contribution to the formation of such arteries, contributing partially or totally to the second DMA in 90%, to the third DMA in 92%, and to the fourth DMA in 86%.

The prevalence of the arcuate artery: a cadaveric study of 72 feet.

The purpose of this study was to quantify the occurrence of the arcuate artery. The arcuate artery was defined as that artery branching off the dorsalis pedis artery at or below the level of the tarsometatarsal joint, tending laterally across the bases of metatarsals 2 through 4, and supplying dorsal metatarsal arteries 2 through 4. The arcuate artery was present in 16.7% of 72 cadaver feet that were dissected and examined, suggesting that the arcuate artery is not the primary blood supply to dorsal metatarsal arteries 2 through 4 as is commonly described. It was determined that the lateral tarsal artery supplied dorsal metatarsal arteries 2 through 4 more frequently (47.2%) than the arcuate artery. The proximal perforating arteries as well as various combinations of all three sources were also found to contribute complete blood supply to dorsal metatarsal arteries 2 through 4. Therefore, a consistent dorsal arterial network, which differentiates throughout development, better explains the blood supply of the dorsal forefoot than the arcuate artery.

The endothelin ET(B) receptor agonist [125I]BQ-3020 binds predominantly to nerves in the bovine retractor penis muscle and penile artery.

Preliminary pharmacological experiments have suggested that in the bovine retractor penis muscle there are relaxation-mediating endothelin ET(B) receptors, at least part of which are located on the inhibitory nitrergic nerves. The present work was undertaken to test this hypothesis by means of receptor autoradiography and additional pharmacological experiments. In the retractor penis muscle and the penile artery, specific binding of the ETB receptor-selective agonist [125I]BQ-3020 took place predominantly to nerve trunks and minor nerve branches. The situation was the same in the dorsal metatarsal artery, that was included as a reference because of its different innervation. Throughout the nerves the silver grains were evenly distributed over the nuclei of Schwann cells and the spaces between them. In the retractor penis there was also a small amount of specific binding to smooth muscle. No specific endothelial binding was observed in any of the tissues examined. The pharmacological studies confirmed that the relaxation of the retractor penis muscle induced by the ET(B) receptor-selective agonist, sarafotoxin S6c, is susceptible to tetrodotoxin as well as to inhibition of nitric oxide synthase. The relaxation was also characterized by inconsistency, weakness and tachyphylaxis. The electrical field stimulation-induced submaximal relaxation of the retractor penis was unaffected by stimulation or blockade of ET(B) receptors. The autoradiography suggests that in all the three bovine tissues studied there are ET(B) receptors located on nerves independently of the type of efferent nerve. The pharmacological experiments do not support the concept that in the bovine retractor penis muscle neuronal ET(B) receptors exert important immediate effects on the functioning of the penile erection-mediating nitrergic nerves.

The Endothelin ETB Receptor Agonist [125I]BQ‐3020 Binds Predominantly to Nerves in the Bovine Retractor Penis Muscle and Penile Artery

Abstract:Preliminary pharmacological experiments have suggested that in the bovine retractor penis muscle there are relaxation‐mediating endothelin ETB receptors, at least part of which are located on the inhibitory nitrergic nerves. The present work was undertaken to test this hypothesis by means of receptor autoradiography and additional pharmacological experiments. In the retractor penis muscle and the penile artery, specific binding of the ETB receptor‐selective agonist [125I]BQ‐3020 took place predominantly to nerve trunks and minor nerve branches. The situation was the same in the dorsal metatarsal artery, that was included as a reference because of its different innervation. Throughout the nerves the silver grains were evenly distributed over the nuclei of Schwann cells and the spaces between them. In the retractor penis there was also a small amount of specific binding to smooth muscle. No specific endothelial binding was observed in any of the tissues examined. The pharmacological studies confirmed that the relaxation of the retractor penis muscle induced by the ETB receptor‐selective agonist, sarafotoxin S6c, is susceptible to tetrodotoxin as well as to inhibition of nitric oxide synthase. The relaxation was also characterized by inconsistency, weakness and tachyphylaxis. The electrical field stimulation‐induced submaximal relaxation of the retractor penis was unaffected by stimulation or blockade of ETB receptors. The autoradiography suggests that in all the three bovine tissues studied there are ETB receptors located on nerves independently of the type of efferent nerve. The pharmacological experiments do not support the concept that in the bovine retractor penis muscle neuronal ETB receptors exert important immediate effects on the functioning of the penile erection‐mediating nitrergic nerves.

Salvage of Free Second Toe with Venous Thrombosis by Shunting Backflow of Second Dorsal Metatarsal Artery-A Case Report

A 26-year-old Thai man underwent free toe transfer for reconstruction of his left band after multi-digit amputation. Unfortunately we encountered a problem of disseminated venous thrombosis. We dissected the thrombotic veins and found that the venous network was occluded by thrombi. Surprisingly, there was a retrograde arterial blood flow in the second dorsal metatarsal artery which immediately relieved the congestion. We shunted the backflow of the SDMA (second dorsal metatarsal artery) with a vein graft and successfully salvaged the free toe.

Extensor Digitorum Brevis Free Flap: Anatomic Study and Further Clinical Applications

The extensor digitorum brevis muscle flap is reliable, safe, and can be used either as a pedicle or as a free flap with minimal donor site morbidity. To increase the existing knowledge of this flap and to establish further anatomic basis for the design and elevation of the extensor digitorum brevis flap, 26 specimens from 13 fresh cadavers were dissected under 3.5 × loupes. The lateral tarsal artery was found to be the main blood supply to the muscle. It has an average diameter of 1.83 ± 0.35 mm and a length of 1.89 ± 0.69 cm. The dorsalis pedis artery has, at the level of the lateral tarsal artery takeoff, a diameter of 3.25 ± 0.62 mm. From this point to the origin of the deep plantar branch, the dorsalis pedis artery has minimal branching, and the surgeon has available an artery homogeneous in diameter that is 6.77 ± 0.99 cm in length. Related neurovascular structures (anterior tibial artery and the venae comitantes, dorsalis pedis and first dorsal metatarsal artery, and deep peroneal nerve) were also studied. A safe and reliable harvesting technique and the “T interposed extensor digitorum brevis” technique for sparing the anterior tibial artery are presented, as are clinical case examples on the use of this flap as a flow-through, extensor digitorum brevis-vascularized nerve graft, a combined extensor digitorum brevis-deep peroneal nerve graft, and a bilobed extensor digitorum brevis-dorsalis pedis fasciosubcutaneous free flap. (Plast. Reconstr. Surg. 105: 1347, 2000.)

Vascular anatomic variations in second toe transfers

To devise a new classification of vascular variations in second toe transfer we analyzed the anatomic details of the first dorsal metatarsal artery in 304 cases of second toe transplantation and the venous structure in 200 cases. According to location, the arterial vascularity was classified as superficial (18% of cases), intramuscular (54%), inframuscular (23%), and absent (5%). According to diameter, it was classified into large (16%), medium (64%), and small (20%). Based on branching pattern, the artery was classified into ramifying type (88%), main trunk (4%), and fine branch type (8%). The venous drainage of the second toe was categorized as greater saphenous vein main trunk type, greater saphenous vein fine branch type, dorsal digital vein main trunk type, and dorsal digital vein fine branch type. Variations of the first dorsal metatarsal artery are common. Classification should be done according to its location, diameter, and branching pattern at the toe web. Regardless of location, big vessels entering the second toe are the most important attribute for successful outcome.

A new technique for the correction of syndactyly of the toes

A new technique is described for the correction of complete syndactyly of the toes. In this technique, a distally-based dorsal metatarsal artery flap is used to cover one side of the released toes. The other side of the toe is covered with a laterally based dorsal toe flap. A case of complete syndactyly between the second toe and and the third toe is presented.

Cardiopulmonary measurements in dogs undergoing gastropexy without gastrectomy for correction of gastric dilatation-volvulus

Objective To measure cardiopulmonary variables, including cardiac index, in dogs with naturally acquired gastric dilatation-volvulus (GDV). Design Prospective clinical study. Animals 6 dogs with GDV. Procedure In addition to typical medical and surgical management of GDV, the dorsal metatarsal and pulmonary arteries and right atrium of the dogs were catheterized to obtain cardiopulmonary measurements before and during anesthesia and surgery. Results All dogs underwent gastropexy but none required gastrectomy. Mean cardiac index and mean arterial blood pressure for this small population of dogs with GDV were not significantly different from those reported for clinically normal awake or anesthetized dogs. Conclusions and Clinical Relevance Dogs with naturally acquired GDV without gastric necrosis may not have the classic characteristics, including decreased cardiac index and hypotension, of hypovolemic circulatory shock. (J Am Vet Med Assoc 1999;215:484—488).

Transmetatarsal amputation of the toe: an analytic study of ischemic complications.

Transmetatarsal amputations of the toes are very common procedures, particularly involving patients with diabetes mellitus and peripheral vascular disease. A complication of these operations is the onset of gangrene of an adjoining toe, which is usually ascribed to the underlying disease. It is suggested that another explanation may be responsible for this occurrence, namely, a combination of the variability of the bifurcation of the dorsal metatarsal arteries and the operative technique. The former is either not described or has different levels in different texts. The operation in nearly all texts is a classic racquet incision, without mention of the width of the racket. The combination of an incision widely diverging from the handle of the racket is in danger of severing the dorsal metatarsal artery, its bifurcation, or the digital branch to the adjacent toe. A patient with a good blood supply may be able to salvage the situation by way of the plantar vessels, but when the vascular status is parlous, which is the case in many amputations, the adjacent digit is at considerable risk. Clinical, radiological, and anatomic evidence is presented to support this contention. Based on the above, a safer operative technique is suggested to avoid possible complications.