Advances in Knowledge In a single institution, extravasation of contrast material into the subcutaneous tissues occurred during attempted intravenous

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1 Note: This copy is for your personal non-commercial use only. To order presentation-ready copies for distribution to your colleagues or clients, contact us at ORIGINAL RESEARCH CONTRAST MEDIA Frequency, Management, and Outcome of Extravasation of Nonionic Iodinated Contrast Medium in Intravenous Injections 1 Carolyn L. Wang, MD Richard H. Cohan, MD James H. Ellis, MD Saroja Adusumilli, MD N. Reed Dunnick, MD 1 From the Department of Radiology, University of Michigan Health System, Room B1D502G, 1500 E Medical Center Dr, Ann Arbor, MI Received March 28, 2006; revision requested May 26; revision received June 5; accepted June 21; final version accepted August 25. Address correspondence to R.H.C. ( Purpose: Materials and Methods: Results: Conclusion: To determine retrospectively the frequency, management, and outcomes of extravasations of intravenously injected nonionic iodinated contrast medium. Institutional review board approval was obtained, and the requirement for informed consent was waived. The study was HIPAA compliant. For intravenous injections of nonionic iodinated contrast medium for computed tomographic examinations between January 1, 2000, and March 31, 2005, the incident reports, radiology reports, and medical records of patients in whom contrast medium extravasations occurred were reviewed. Data collected included patient age, catheter gauge, injection site, volume extravasated, patient symptoms, severity of injury, treatment, whether or not the plastic surgery service was consulted and any additional treatment that service instituted, and patient outcome. Extravasations occurred in 475 (0.7%) of patients, and follow-up information was available for 442 adults (280 women, 162 men; mean age, 57 years) and 17 children (nine girls, eight boys; mean age, 6 years). Extravasated volumes ranged from 3 to 150 ml. Symptoms usually consisted of swelling and/or pain. The plastic surgery service was consulted for 38 adults and six children and provided additional treatment in eight patients (seven adults, one child). Among adults, 432 had minimal or no adverse effects, nine had moderate adverse effects, and one had a severe complication (75 ml of contrast material extravasated into the hand, causing compartment syndrome). Only one moderate or severe complication in an adult resulted from an extravasation of less than 50 ml. Fifteen children had minimal or no adverse effects, one had moderate adverse effects, and one had a severe complication (18 ml of contrast material extravasated into the arm, causing brachial plexopathy). Extravasation of nonionic iodinated contrast medium results only rarely in moderate or severe adverse effects, and these usually occur only when large volumes of contrast medium are involved. RSNA, 2007 RSNA, Radiology: Volume 243: Number 1 April 2007

2 Advances in Knowledge In a single institution, extravasation of contrast material into the subcutaneous tissues occurred during attempted intravenous injection in less than 1% of patients (475 [0.7%] of injections), often involved large volumes of contrast material ( ml in 119 [26%] of 453 extravasations for which estimated extravasation volumes were available), and nearly always resolved with conservative management. Moderate or severe extravasation injuries developed in a small number of patients (10 [adults] and two [children] of 459 patients with sufficient follow-up data), even when large volumes of contrast medium were involved. Extravasation of iodinated radiographic contrast material is a wellknown complication of iodinated radiographic contrast material injection, occurring even when appropriate intravenous injection techniques are used. In earlier series, the rate of extravasation during computed tomography (CT) was estimated to be 0.03% 0.17% (1 3). Later reports with larger numbers of patients, published after automated mechanical injectors began to be routinely used for contrast material injection, demonstrated higher extravasation rates ranging from 0.25% to 0.9% (4 6). The majority of extravasation injuries resolve without adverse effects (7); however, severe extravasation injuries have been reported after administration of both ionic (8 12) and nonionic contrast materials (13 16), and some have resulted in tissue loss and neurovascular and musculoskeletal compromise (8 16). Multiple surgical procedures may be needed to treat these complications in some patients (8,9). Few data exist on the frequency of contrast medium extravasations and the resulting complications. For example, to our knowledge the three largest published series (4 6) on this topic to date included only 140 extravasations altogether, 66 of which involved nonionic contrast material. No severe complications from the extravasations were observed in any of these series or reported in a more recent study of 11 extravasations (17). The purpose of our study was to determine retrospectively the frequency, management, and outcome of intravenous nonionic iodinated contrast medium extravasations. Materials and Methods Injection Technique and Extravasation Management At our institution, intravenous injections for CT examinations are performed and monitored by radiologic technologists, all of whom have received training in intravenous injection technique. Injections are performed with automated injectors (Stellant; Medrad, Indianola, Pa) whenever possible, through intravenous catheters (Becton-Dickinson, Sandy, Utah) placed preferentially in the antecubital fossa. If venous access cannot be established in the antecubital fossa, veins in the forearm, hands, or, rarely, lower extremities may be used. In adults, the technologists are encouraged to use catheters that are at least 20 gauge whenever possible; 22- gauge intravenous catheters are reserved for adult patients in whom intravenous access is difficult and has to be established in small veins. Occasionally, indwelling intravenous catheters are used after the technologist establishes patency. The policy at our children s hospital is to choose 22-gauge catheters, although 20-gauge catheters are preferred in young adults and 24-gauge catheters are preferred in very young children. As in adults, in young patients, the catheters are preferentially placed in the antecubital fossa, with the hand the next most preferred site. At both hospitals, injections were not made through peripherally inserted central catheter lines, since the newer ones that permit power injection (PowerPICC power injection catheter; Bard Access Systems, Salt Lake City, Utah) were not used during the study period. However, a nurse or physician can inject contrast medium by hand through a central line, arterial line, or port. The technologists test each intravenous catheter through which contrast material is to be administered by briskly hand injecting saline through it. Once patency is established, the contrast medium injection can be started. Unless otherwise specified by the manufacturer, contrast material is warmed to body temperature before injection; this reduces viscosity. The technologist closely monitors the injection site from the commencement of injection to the beginning of scan acquisition. This allows the technologist to remain with the patient for seconds after initiation of contrast material injection. The patient is instructed to report any injection site discomfort. At completion of CT scanning, the injection site is inspected by the technologist for swelling or erythema. In November 1994, our radiology department, in conjunction with the section of plastic surgery of the department of surgery, adopted a formal policy for documentation, management, and follow-up of patients with contrast material extravasation. Initial treatment of a patient in whom an extravasation is identified consists of application of ice packs or cold compresses to the extravasation site and elevation of the affected extremity above the level of the heart. A radiology resident or attending radiologist inspects each extravasation, and the patient is then monitored in the radiology department for up to 2 4 hours. Published online /radiol Radiology 2007; 243:80 87 Abbreviation: EEV estimated extravasated volume Author contributions: Guarantors of integrity of entire study, C.L.W., R.H.C., N.R.D.; study concepts/study design or data acquisition or data analysis/interpretation, all authors; manuscript drafting or manuscript revision for important intellectual content, all authors; manuscript final version approval, all authors; literature research, C.L.W., R.H.C., N.R.D.; clinical studies, C.L.W., R.H.C., N.R.D.; and manuscript editing, all authors Authors stated no financial relationship to disclose. Radiology: Volume 243: Number 1 April

3 A consultation from the plastic surgery service is obtained if any of the following five criteria are met: (a) Extravasation volume is estimated to be 100 ml or more of nonionic contrast medium, (b) skin blistering occurs, (c) there is evidence of altered tissue perfusion, (d) pain at the extravasation site increases over time, and/or (e) there is a change in sensation at or adjacent to the extravasation site. The radiologist completes a departmental incident data form for contrast material extravasation, which includes patient identifying information, type and estimated volume of extravasated contrast material, site of extravasation, gauge of catheter used for the injection, patient signs and symptoms after extravasation, treatment instituted, and whether the plastic surgery service was consulted. These forms are filed in the radiology department for quality assurance monitoring and to facilitate follow-up. Study Group Institutional review board permission was obtained to access pertinent imaging and medical records of the patients involved in this study. The submitted institutional review board proposal was deemed to be compliant with both institutional requirements and the Health Insurance Portability and Accountability Act. Waiver of informed consent was granted. Between January 1, 2000, and March 31, 2005, there were intravenous injections of nonionic contrast medium for CT at our institution, in adults and 7741 in children. During this period, nonionic iodinated contrast material was used for all contrast material enhanced (iohexol 300 [Omnipaque 300; GE Healthcare, Waukesha, Wis]; iopromide 300 or 370 [Ultravist 300 or 370, respectively; Berlex Laboratories, Montville/Wayne, NJ]; or iodixanol 320 [Visipaque 320; GE Healthcare]) CT examinations. For this study, all of the contrast material extravasation incident data forms completed between January 1, 2000, and March 31, 2005, were reviewed by one of two authors (C.L.W. or R.H.C.). Data obtained from these forms included patient sex, patient age, type of contrast material extravasated, injection site, intravenous catheter gauge, contrast material injection rate, estimated extravasated volume (EEV), immediate symptoms (if any), initial treatment, and whether or not plastic surgery consultation was obtained. Medical records and radiology reports in the same patients were also reviewed by one of the same two authors (C.L.W. or R.H.C.) to determine the duration of symptoms, final outcome, and total duration of patient follow-up. Progress notes generated on the day of the extravasation and for at least 2 months after the extravasation were reviewed for mention of any adverse effects or treatment related to the extravasation. When adverse consequences were noted, additional progress notes were examined until patient symptoms had resolved or the instituted treatment was completed. Each extravasation was classified by consensus between two authors (C.L.W. and R.H.C.) as producing mild, moderate, or severe injury. Mild extravasation injuries were those in which signs and symptoms were absent or consisted of only pain, swelling, and/or mild erythema, which resolved with limited treatment of elevation and administration of ice packs or cold compresses. No additional treatment was administered, and there was no mention of any adverse effects on the departmental extravasation form, in the dictated radiology report, or in any follow-up progress or clinic notes. Moderate extravasation injuries were those in which more severe initial manifestations were present, such as moderate or severe erythema, blistering, or marked pain or swelling, or injuries in which additional treatment was instituted, regardless of initial manifestations. However, to be considered moderate, all signs and symptoms had to have resolved within 2 weeks of the extravasation. Severe extravasation injuries either produced long-term adverse effects (lasting more than 2 weeks), such as unremitting pain, swelling, and limitations in extremity movement, or required surgical intervention. The medical records of patients who experienced moderate or severe extravasation were reviewed to assess for the presence of any risk factors (such as a history of diabetes mellitus or upper-extremity vascular or circulatory problems) that might explain why only these patients were affected adversely. Results Contrast material extravasation forms were completed for 476 (0.7%) of nonionic contrast material injections. One patient was determined by the evaluating radiologist and clinical service not to have had contrast material extravasation but rather to have experienced transient pain at the injection site without extravasation; this patient was therefore excluded. In 16 other patients, either the follow-up was inadequate, so the severity of the extravasation injury could not be determined (n 13), or the extravasation was thought to involve only the preliminarily injected saline flush (n 3). These patients were also excluded from further consideration. Therefore, completed extravasation forms were available for 459 patients in whom there were adequate follow-up data (mean follow-up, 18 months; range, 1 day to 67 months) and in whom the extravasation was deemed to involve nonionic iodinated contrast medium. These patients included 442 adults (280 women, 162 men; age range, years; mean age, 57 years) and 17 children (nine girls, eight boys; age range, neonate to 17 years; mean age, 6 years). The type of extravasated contrast material was recorded for 454 of the 459 extravasations. Iohexol 300 was extravasated in 387 patients (85%); iopromide 300, in 44 (10%); iodixanol, in 12 (3%); and iopromide 370, in 11 (2%). This distribution reflects the fact that iohexol was used almost exclusively between January 2000 and October 2004, with iopromide used between October 2004 and March 31, Iodixanol was administered to only a small group of patients with preexisting renal insufficiency. Precise data on the number of times each type of contrast material was injected were not available. No patient experienced more than one extravasation episode. Extravasations in Adults Injection site, injection rate, catheter gauge, and volume extravasated. The 82 Radiology: Volume 243: Number 1 April 2007

4 extravasation site was not mentioned for five patients. The most common extravasation site in the remaining 437 patients was the antecubital fossa (n 196 [44.8%]). Other recorded extravasation sites were the forearm (n 99 [22.6%]), hand (n 47 [10.8%]), arm (n 41 [9.4%]), wrist (n 29 [6.6%]), upper arm (n 16 [3.7%]), shoulder (n 5 [1.1%]), foot (n 2 [0.5%]), neck (n 1 [0.2%]), and groin (n 1 [0.2%]). The injection rate was not recorded for 21 adults. Of the remaining 421 adult patients, 113 (27%) were injected at rates of less than 2 ml/sec; 212 (50%), at rates of 2 3 ml/sec; and 96 (23%), at rates exceeding 3 ml/sec. The gauge of intravenous catheter used was not specified for 16 adult patients. For the remaining 426 adults, 22-gauge catheters were used in 125 (29%) and 20-gauge catheters were used in 284 (67%) patients. The remaining patients were injected through 18-gauge (n 14), 16-gauge (n 2), or 14-gauge (n 1) catheters. The volume of contrast medium extravasated was not recorded for six patients. The EEV was less than 10 ml in 45 (10%) of the remaining 436 patients, ml in 276 (63%), ml in 54 (12%), and ml in 61 (14%). Symptoms and initial treatment (including plastic surgery consultation). The most commonly reported symptoms in the 442 adult patients were swelling (including descriptions of bump, edema, or induration) in 350 patients (79%) and pain in 106 (24%). The absence of symptoms was reported for 36 (8%) patients. One of these patients was noted to be unresponsive (due to a preexisting medical condition). For four patients the incident report sheet did not mention whether or not symptoms were present. Most patients (n 241) were treated with cold compresses or ice packs, and elevation. Some patients received ice packs or cold compresses alone (n 144) or elevation alone (n 2). Although our policy was to use ice rather than warmth, three patients were treated with warm compresses and elevation, while three others had warm compresses applied without elevation. One patient received ice packs followed by warm compresses, and another patient received ice and topical hydrogen peroxide. In 38 patients the radiology resident or staff deemed that no treatment was necessary. In nine cases, no treatment was recorded. Although our policy requires plastic surgery consultation for all patients whose extravasations involve 100 ml or more of contrast medium, the medical records documented such a consultation for only 32 (52%) of the 61 patients in this group. Plastic surgery consultations were also performed for six other patients owing to symptoms. The 38 evaluations led to additional treatment in seven patients. The additional treatment consisted of hand splints (n 3), topical silver sulfadiazine (Silvadene; King Pharmaceuticals, Bristol, Tenn) application to blisters or open arm wounds (n 2), use of a stockingette (a tubular bandage) (n 1), or surgery (n 1). In two patients, additional therapy was administered by another medical service already caring for the patient. One of the previously mentioned patients who had received a splint also received a subcutaneous injection of colchicine administered by the clinical inpatient service, as his extremity discomfort was believed to be due to aggravation of gout rather than extravasation. An additional patient (who was not evaluated by the plastic surgery service) received systemic antibiotics for presumed cellulitis. Severity of extravasation injuries. Of the extravasation injuries, 432 were considered mild. Initial symptoms in these patients, if any were present, resolved without the need for any treatment other than ice or cold compresses and elevation, and there were no short- or longterm adverse consequences. There were nine moderate extravasation injuries involving a wide range of EEVs ( ml). Symptoms that resulted in the classification of these reactions as moderate included blistering (n 3); persistent firmness, swelling, and/or pain (n 3); ulceration (n 1); discrete areas of persistent edema (n 1); numbness (n 1); suspected inflammation in the affected extremity, which was diagnosed 1 week after the extravasation (n 1); open arm wounds (n 1) (the term used in the patient s medical records); and ecchymosis (n 1). In each of these patients, symptoms had resolved completely at 2-week follow-up (Table 1). There was a single severe extravasation injury, in a 48-year-old woman who had an EEV of 75 ml of iohexol in the dorsum of her left hand. Immediately after the extravasation occurred, the patient had swelling and pain, and within 30 minutes progressive bluish discoloration and numbness had developed in her fifth digit. The affected extremity was immediately elevated, and cold compresses followed by ice packs were applied. The plastic surgery service was called to evaluate the patient and measured elevated compartment pressures. The patient subsequently underwent a left-hand dorsal fasciotomy, evacuation of subcutaneous contrast medium and fluid, and placement of a volar splint. At her 1-month follow-up, she was noted to have minimal residual injury, with a small healing scar on the dorsum of her hand (Fig 1) but no functional impairment. The frequencies of the different severities of extravasation injury were calculated for different EEVs. All but one of the moderate or severe injuries occurred with extravasations of 60 ml or more (Table 2). In one patient, an extravasation of 10 ml into the forearm led to a moderate injury consisting of firmness, pain, numbness, and blistering. When extravasations were grouped according to volume, the largest difference in the frequency of moderate or severe injuries occurred between volumes smaller than 50 ml (total frequency, 0.3%) and volumes of 50 ml or more (total frequency, 8.0%) (Table 2). There were three moderate extravasation injuries in patients injected at rates lower than 2 ml/sec, three moderate or severe injuries in patients injected at rates of 2 3 ml/sec, and four moderate injuries in patients injected at rates exceeding 3 ml/sec. Seven of the 10 patients with moderate or severe injuries were injected through 20-gauge intravenous catheters, and one was in- Radiology: Volume 243: Number 1 April

5 jected through a 22-gauge intravenous catheter. Catheter size was not recorded in the remaining two patients (including the patient with the severe injury). The distribution in injection rates and catheter sizes for patients with moderate or severe extravasation injuries was similar to that in the entire group of 442 adults with extravasations. Of the 10 patients with moderate or severe injuries, six (60%) were injected with iohexol 300; three (30%), with iopromide 300; and one (10%), with iodixanol. This distribution reflects the fact that iohexol was administered to many more patients than were the other agents during the study period. The patients with moderate or severe extravasation injuries had a large number of medical conditions, but only a few of these conditions might have placed these patients at increased risk of an adverse effect after extravasation. Two of the 10 patients had connective tissue diseases (one had rheumatoid arthritis, and the other had systemic lupus erythematosus), one had type II diabetes mellitus, and one had had a single episode of lower-extremity deep vein thrombosis 1 year earlier. Other existing medical conditions in these patients included a history of cancer (n 3), pancreatitis (n 2), chronic lymphocytic leukemia, coronary artery disease, dehydration, dementia, emphysema, hypertension, hyperthyroidism, hypothyroidism, idiopathic thrombocytopenic purpura, inflammatory bowel disease, peptic ulcer disease, pneumonia, postoperative state, pseudomembranous colitis, and/or urinary tract infection (each n 1). Extravasations in Children Injection site, injection rate, catheter gauge, and extravasated volume. A variety of extravasation sites were observed in children: the antecubital fossa (n 4), arm (n 4), hand (n 3), and six other sites (shoulder, forearm, wrist, groin, ankle, and foot; each n 1). One of these extravasations occurred from an indwelling catheter placed in the left upper arm, the tip of which was located near the shoulder. The remaining extravasations occurred from catheters placed specifically for the injection of contrast material. Eleven of the pediatric injections were performed at slow rates by hand. Automated injectors were used in five other patients, with a rate of 1.5 ml/sec used in three of these patients; 2 ml/sec, in one; and 2.5 ml/sec, in one. The injection method and rate were not recorded for the last patient. Catheters used for contrast material injection were 24 gauge (n 4), 22 gauge (n 6), 20 gauge (n 2), and 16 gauge (n 1). For four children, the catheter gauge was not recorded. EEVs ranged from 4 to 125 ml. Volumes of 0 9 ml were seen in three children; volumes of ml, in 10; volumes of ml, in one; and volumes of ml, in three. The five largest extravasation volumes (125, 100, 100, 80, and 40 ml) were in children older than 12 years. The largest extravasation volume in a young child was 24 ml into the antecubital fossa of a 1-year-old patient, which resolved without adverse effects. Symptoms and initial treatment (including plastic surgery consultation). The most commonly encountered clinical sign was swelling (13 children). Only four children reported having pain, in part because many children were too young to communicate with the health care providers. Initial treatment consisted of ice packs or cold compresses along with elevation in six patients, ice packs or cold compresses alone in six, and warm compresses in one. No treatment was mentioned for the remaining four patients. Plastic surgery consultation was documented in six instances. In two, the admitting service was notified of the extravasation and advised to consult the plastic surgery service; however, there were no notes indicating that these patients were subsequently examined by plastic surgery personnel. Table 1 Moderate and Severe Extravasation Injuries in Adults Patient No./ Age (y)/sex EEV (ml) Location of Extravasation Severity of Injury Symptoms Treatment* Follow-up Duration 1/59/M 150 Forearm Moderate Four areas of edema Silver sulfadiazine 5 mo 2/74/F 134 Antecubital Moderate Hardened mass over biceps, 1-cm area of blistering Silver sulfadiazine 11 mo 3/45/F 125 Antecubital Moderate Swelling, mild edema in biceps Splint 16 mo 4/69/F 100 Antecubital Moderate Ecchymosis, tense arm Splint 1 mo 5/40/F 80 Antecubital Moderate Tense forearm, pain with motion Stockingette 16 mo 6/70/M 80 Arm Moderate Delayed swelling at 1 week, no definite cellulitis Antibiotics 9 d 7/71/M 75 Antecubital Moderate Skin ulceration, erythema Splint, colchicine 1 mo 8/48/F 75 Hand Severe Paresthesias, numbness, blue discoloration in fifth digit Fasciotomy 49 mo 9/30/M 60 Forearm Moderate Three blisters 2 days later None 40 mo 10/41/F 10 Forearm Moderate Firmness, blisters, pain, and numbness None 36 mo Note. Patients (10 of 442 patients) are listed in order of decreasing EEV. Symptoms resolved within 2 weeks in all patients except patient 8, who had a severe injury that necessitated surgery and in whom functional impairment resolved within 1 month of the injury. * Treatment other than ice or cold compresses and elevation. 84 Radiology: Volume 243: Number 1 April 2007

6 Additional treatment was instituted by the plastic surgery service in one child. The pediatric service instituted additional treatment in one other child. Severity of extravasation injuries. Fifteen of the pediatric extravasation injuries were classified as mild; one was classified as moderate, and one was classified as severe. The moderate injury was encountered in a 16-year-old patient with traumatic brain injury in whom upper-extremity venous thrombosis developed 1 week after extravasation of 100 ml of iohexol through a 20- gauge catheter placed in the left arm. The patient was treated by the pediatric inpatient service with anticoagulants, and the thrombosis resolved without additional morbidity. While the clinical service believed that the thrombosis was very likely not due to the contrast material injection, since it developed 7 days after it, this patient was considered to have a moderate extravasation injury because a relationship between the extravasation and the thrombosis could not be excluded with certainty. The single severe injury involved a 22-month-old girl who had a history of severe reflux and had recently undergone removal of an esophageal leiomyoma. After 18 ml of iohexol was injected through an indwelling catheter placed in her upper left arm, left upperextremity movement ceased. On the CT scan, extensive extravasation was noted in the left axilla, extending over the apex of the left lung and dissecting into the left spinal canal via neural foramina at the C7, T1, and T2 vertebral levels (Fig 2). No intravascular contrast medium was seen. Magnetic resonance imaging revealed heterogeneous fluid in the left brachial plexus region. A follow-up CT scan of the brachial plexus 17 days later demonstrated reabsorption of the contrast material; however, there was infiltrative soft tissue surrounding the brachial plexus, which was presumed to represent a combination of fibrosis and residual edema. The Figure 1 Figure 1: Severe extravasation injury in an adult patient. (a) Preoperative photograph shows that the affected hand is swollen and that the fingers are dusky. Compartment syndrome was diagnosed. (b) Photograph obtained during surgery demonstrates the surgical incision. A dorsal fasciotomy was performed, and contrast medium and fluid were evacuated from the dorsum of the hand. (c) Photograph taken 1 month after surgery demonstrates only a small eschar at the fasciotomy site. Radiology: Volume 243: Number 1 April

7 Table 2 Figure 2 Distribution of EEV and Severity of Injury in 436 Adults for Whom Volume Data Were Available Severity of Injury EEV 0 9 ml ml ml ml Total Severe (2) 0 1 Moderate 0 1 (0.4) 4 (7) 4 (7) 9 Mild 45 (100) 275 (99.6) 49 (91) 57 (93) 426 Total Note. Data are numbers of patients, with percentages (based on values in Total row) for each volume group in parentheses. patient was followed up by the plastic surgery, neurosurgery, and physical medicine and rehabilitation services for her brachial plexopathy and underwent physical therapy. Electromyography performed 10 weeks later revealed damage to the ulnar and median nerves. The patient demonstrated marked improvement by the 4th month after the event, and there were no noticeable deficits at 1-year follow-up. Discussion Our observed extravasation rate of 0.7% (475 of patients) is similar to that encountered in other series in which automated mechanical injectors were used, where the extravasation rates ranged between 0.25% and 0.9% (4 6). Although the single most common extravasation site in our series was the antecubital fossa, most of our patients had extravasations elsewhere, probably because intravenous access in the antecubital fossa was difficult in these patients. In an earlier report (4) comparing 51 patients who had extravasations with 100 control patients who did not, a higher percentage of patients with extravasations were found to have been injected outside the antecubital fossa (39% for patients with extravasations vs 24% for patients without extravasations). Although the technologists are instructed to inject adults through a 20-gauge intravenous catheter (or a larger-bore catheter), over 100 adults in our series were injected through 22-gauge catheters; this factor suggests that many punctured veins were small. As in previous series, in our study many of the extravasations involved large volumes of contrast material. Although the most frequently observed range of extravasated contrast material volumes was ml (in 276 of 436 adult patients and 10 of 17 children for whom volume estimates were available), extravasation volumes of ml (in 54 adults and one child) and ml (in 61 adults and three children) were encountered fairly often. In our study, most patients were initially treated with only ice packs or cold compresses, along with elevation. Plastic surgery consultation was documented for only 44 patients (38 adults and six children), even though 64 patients (61 adults and three children) met the local criteria for such consultation because of the estimated volume of contrast material extravasated. However, only rarely did plastic surgery consultation result in additional therapy (in seven adults and one child), and even then the therapy was minimal in all but two patients. It consisted of splints, stockingette, or topical application of silver sulfadiazine in six adults, fasciotomy in one adult, and prolonged physical therapy in one child. Our results confirm the rarity of moderate or severe extravasation injuries. The majority of extravasation injuries resolved shortly after they occurred, requiring only minimal conservative treatment. Of the 459 patients with extravasations and available follow-up data, only 12 had moderate or severe injuries and only one required surgery, to which the patient responded well. The next most severe injury, brachial plexopathy, was noted in a 22- Figure 2: Severe extravasation injury in a pediatric patient. Transverse contrast-enhanced chest CT scan demonstrates extravasation of nonionic iodinated contrast medium into the left axilla, over the lung apex, and dissecting into the left spinal canal via the left T2 neural foramen. month-old child and had completely resolved 1 year later. Moderate or severe extravasation injuries were observed most commonly when larger volumes of contrast material were extravasated; however, our results did not justify our preexisting policy of requiring plastic surgery consultation when the EEV was 100 ml or more. The case of compartment syndrome developed after extravasation of 75 ml. Only five of the 10 moderate extravasation injuries involved EEVs of 100 ml or more, and, surprisingly, one moderate injury occurred after extravasation of only 10 ml of contrast medium. In fact, for adults and children combined, the extravasation volume range that was associated with the highest moderate or severe injury rate was ml (five of 55 patients [9.0%], compared with five of 64 patients [8.0%] in the mL group and two of 286 [0.7%] in the mL group). However, our results also suggest that the plastic surgery consultation resulted in very few important treatment changes. It therefore seems that only signs and symptoms should be used as criteria for plastic surgery consultation and additional treatment. Our study had a number of important limitations. First, it was a retrospective review, and, as such, was entirely depen- 86 Radiology: Volume 243: Number 1 April 2007

8 dent on the quality, accuracy, and completeness of the extravasation data forms and the medical records. It is likely that the extravasation rate was underestimated, as some small-volume extravasations may not have been documented. Also, some information (eg, injection site, intravenous catheter gauge, and patient symptoms) was not provided for a few patients. Follow-up was not complete for all of the known extravasations, but our observation that moderate or severe adverse consequences were rare is probably still justified, because if additional treatment of an extravasation had been required, this occurrence probably would have been detected and documented. Extravasation of contrast material often involves large volumes of contrast material and nearly always resolves with conservative treatment. Moderate injuries occur with a small number of extravasations, and severe injuries are even less frequent, even when large volumes of contrast medium are involved. References 1. Cohan RH, Dunnick NR, Leder RA, Baker ME. Extravasation of nonionic radiologic contrast media: efficacy of conservative treatment. Radiology 1990;176: Miles SG, Rasmussen JF, Litwiller T, Osik A. Safe use of an intravenous power injector for CT: experience and protocol. Radiology 1990;176: Sistrom CL, Gay SB, Peffley L. Extravasation of iopamidol and iohexol during contrast-enhanced CT: report of 28 cases. Radiology 1991;180: Bullard MA, Cohan RH, Ellis JH, Jan SH, Francis IR, Dunnick NR. Extravasation of intravenous contrast material: incidence, management, outcome. Acad Radiol 1997;4: Federle MP, Chang PJ, Confer S, Ozgun B. Frequency and effects of extravasation of ionic and nonionic CT contrast media during rapid bolus injection. Radiology 1998;206: Jacobs JE, Birnbaum BA, Langlotz CP. Contrast media reactions and extravasation: relationship to intravenous injection rates. Radiology 1998;209: Cohan RH, Ellis JH, Garner WM. Extravasation of radiographic contrast material: recognition, prevention, and treatment. Radiology 1996;200: Upton J, Mulliken JB, Murray JE. Major intravenous extravasation injuries. Am J Surg 1979;137: Leung PC, Cheng CY. Extensive local necrosis following the intravenous use of x-ray contrast medium in the upper extremity. Br J Radiol 1980;53: Ayre-Smith G. Tissue necrosis following extravasation of contrast material. J Can Assoc Radiol 1982;33: Burd DA, Santis G, Milward TM. Severe extravasation injury: an avoidable iatrogenic disaster? Br Med J (Clin Res Ed) 1985;290: Loth TS, Eversman WM. Extravasation injuries in the upper extremity. Clin Orthop Relat Res 1991;272: Pond GD, Dorr RT, McAleese KA. Skin ulceration from extravasation of low-osmolality contrast medium: a complication of automation. AJR Am J Roentgenol 1992;158: Memolo M, Dyer R, Zagoria RJ. Extravasation injury with nonionic contrast material. AJR Am J Roentgenol 1993;160: Young RA. Injury due to extravasation of nonionic contrast material [letter]. AJR Am J Roentgenol 1994;162: Benson LS, Sathy MJ, Port RB. Forearm compartment syndrome: forearm compartment syndrome due to automated injection of computed tomography contrast material. J Orthop Trauma 1996;10: Sinan T, Al-Khawari H, Chishti RA, Al Saeed OM, Sheikh M. Contrast media extravasation: manual versus power injector. Med Princ Pract 2005;14: Radiology: Volume 243: Number 1 April