2025 Acute Complications of Central Line Placement in Profoundly Thrombocytopenic Cancer Patients Rafael Barrera, M.D.' Bushra Mina, M.D.' Ying Huang, Ph.D.2 Jeffrey S. Groeger, M.D.' ' Critical Care Medicine Service, Department of Anesthesiology and Critical Care Medicine, Memorial Sloan-Kettering Cancer Center Cornell University Medical College, New York, New York. * Biostatistics Service, Department of Epidemiology and Biostatistics, Memorial Sloan-Ketteriiig Cancer Center, Cornell University Medical College, New York, New York. BACKGROUND. Morbidities associated with the insertion of central venous catheters in severely thrombocytopenic cancer patients were analyzed in this prospective observational study. One hundred fifteen consecutive thrombocytopenic patients requiring central venous access (internal jugular or subclavian vein cannulation by a modified Seldinger technique) were evaluated. METHODS. One hundred fifteen catheters were inserted. For each patient, the following factors were documented: age; sex; diagnosis; previous catheterization; prior neck, chest, breast, or axillary surgery or radiation therapy; presence of other lines prior to venipuncture; site and indication for line insertion; complications; PT and PTT; platelet counts; and hematocrit. RESULTS. Of the total number of catheters inserted, 63 (55%) were subclavian and 52 (45%) were internal jugular. Successful cannulations with no complications (n = 91; 79% of the total) were achieved with 1.2 5 0.5 attempts. Twenty-four major and minor complications (20%) occurred with an average of 1.6 i 1 attempts ( P = 0.003). The mean preprocedure platelet counts were 14.8 5 4.5 x 10y/Lfor the subclavian group and 14.3 t 4.8 x 109/L for the internal jugular group. With platelet transfusion, the mean postprocedure platelet counts for the subclavian and internal jugular groups were 23.9 2 12.8 x 109/L and 24.6 2 15 x 10"/L, respectively. In the subclavian group, seven patients (6%)experienced minor complications. There were 17 minor complications (15%)and 1 pneumothorax in the internal jugular group. Patients experiencing more than one attempt at cannulation had more complications ( P = 0.003). CONCLUSIONS. With the appropriate precautions and platelet transfusions, central venous catheters can be inserted safely with minimal complications into thrombocytopenic cancer patients. Fewer attempts are associated with fewer complications. High risk procedures should be attempted only by experienced personnel or under their direct and strict supervision. Cancer 1996; 782025-30. 0 1996 American Cancer Society. KEYWORDS: central line, thrombocytopenia, complications, catheterization. T Address for reprints: Jeffrey S. Groeger, M.D., Medical Director, Special Care Unit, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021. Received July 15, 1996; revision received August 1, 1996; accepted August 1, 1996. 0 1996 American Cancer Society he nature and the magnitude of complications associated with central venous catheterization are related to the invasiveness of the procedure, the operator's experience, and the patient's clinical condition. Common complications are bleeding and hematoma.',2 Reports of mechanical complications after initial insertion vary from 1.3%to 11%,and may include pneumothorax, hemothorax, and injury to great vessel^.^-'^ A quantitative relationship between the platelet count and the occurrence of spontaneous hemorrhage exists. The incidence of spontaneous hemorrhage is greater than 50% with platelet counts < 20 x 109/Lin patients with acute leukemia,15whereas in patients with solid 2026 CANCER November 1, 1996 / Volume 78 / Number 9 tumors, the incidence is below 12% with platelet counts > 10 x io9/L.l6 Thrombocytopenic cancer patients present a dilemma for central venous access. Some investigators consider the safest sites, with the least potential for bleeding complications, to be a percutaneous approach into the external jugular vein or the antecubital fossa, or via a cutdown. Although a cutdown offers advantages for prevention and control of hemorrhage, in neutropenic patients it presents a significant risk for infe~tion.'~ Insertion of a femoral vein line is reasonably safe, particularly if a low femoral approach is used. However, the incidence of contamination is frequent.' Some investigators have demonstrated that central venous catheterization can be performed safely in the thrombocytopenic patient without an increase in complications.'4"8Although it is impossible to specify an absolute platelet count below which the risk of hemorrhage contraindicates a surgical or invasive procedure, a platelet count > 50 x 109/L is recommended during any inter~ention.'~ The aim of this study was to evaluate the incidence of complications related to venous cannulation in severely thrombocytopenic patients described as having a platelet count 5 20 x i09/L. MATERIALS AND METHODS A prospective quality assurance project from July 1990 to September 1993, evaluating the incidence of complications related to cannulation of the internal jugular and subclavian veins in profoundly thrombocytopenic patients, was performed. As per hospital policy, central line insertion in thrombocytopenic patients is performed, upon request, by the Critical Care Medicine Service. Profound thrombocytopenia in the current study was defined as platelet count of 520 x 109/L before platelet transfusion. In the current study institution, the level of expertise for venous cannulation varied among the Critical Care fellows; however, all fellows performed between 25 to more than 100 central line cannulations in their primary training program and were certified to perform these high risk procedures after direct observation by a Critical Care Medicine Service attending physician. Only central line placements performed by the Critical Care staff were evaluated during that period. Critical care house staff recorded each patient's age, sex, diagnosis, previous catheter placement, neck surgery, or radiation therapy. Site of line, complications, attempts, line tip, transfusions, prothrombin time (PT) and partial thromboplastin time (PTT), pre- and postprocedure platelet count, and hematocrit were also obtained by observation and chart review. Indications for the line were specified for each patient. There were eight dif- ferent inserters and their level of experience in line placement was not recorded. The central venous catheters were inserted in patients in the combined medical-surgical intensive care unit or on the regular wards of Memorial Sloan-Kettering Cancer Center. Catheters were inserted by the Critical Care fellows; all insertion attempts were observed and self-reported. Patients with an initial platelet count 5 20 x 109/L required platelet transfusion in an attempt to raise the platelet count 2 20 x 109/L. The number of platelet units transfused prior to the cannulization varied according to the initial platelet count and the clinical setting. The number of platelet units transfused was recorded, as was the posttransfusion platelet count. Patients with prolonged PT and PTT received two units of fresh frozen plasma in an attempt to correct coagulopathies. No posttransfusion PT and PTT were done. The site of the venipuncture that would provide the least morbidity to the patient was selected. There was no systematic algorithm for venipuncture site selection. The site was selected according to the patient's or the inserter's preference, viability of the site, history of previous unsuccessful or difficult attempts, and distortion of the anatomic landmarks either due to neck/truncal obesity or prior neck/chest/breast/axillary radiation or surgery. The procedures were performed under local anesthesia, without utilization of fluoroscopic or sonographic visualization. Venipuncture was performed either during or immediately after platelet transfusion. Triple lumen central venous catheters (7 French) or Introducer Sheaths (8 French) were inserted aseptically using a modified Seldinger technique with a 18gauge (6.35 cm) needle. After the catheter had been successfully inserted, the site was inspected for any evidence of bleeding, oozing, or hematoma. The puncture site and the surrounding skin were cleansed with povidone-iodine and alcohol swabs, and sterile Tegaderm transparent dressings (3M, Medical-SurgicalDivision, St. Paul, MN) were applied. Any complications encountered during the procedure were evaluated. The number of attempts, defined as skin puncture and any interventions taken, were self-recorded. Postprocedure chest radiographs were obtained for verification of the catheter's position and to evaluate the possibility of complications related to the procedure. After 24 hours, the patients were interviewed, the sites inspected, and the nurse's notes reviewed for any evidence of late complications. Major complications were defined as bleeding from the site requiring blood transfusion, malposition of the catheter, hydro/pneumothorax, or mediastinal hematomas. Minor complications were defined as oozing of blood and/or small hematomas < 5 cm at the cannulation site not requiring therapy. Late occurring complications such as Central Line Placement in Profoundly Thrornbocytopenic PatientdBarrera et al. TiLBLE 1 Comparison of Selected Clinical Characteristics of Subclavian and Internal JugularVein Cannulations 2027 TABLE 2 Complications bv Site Observed complications (N = 24) No. Platelets, preprocedure (1O''iL) Platelets, postprocedure (lO'/L) Hematocrit, preprocedure (%) Hematocrit, postprocedure (%) Prothrombin time (seconds) Partial thromboplastin time (seconds) No. complications ( P = 0.005) Diagnosis Solid tumor Lymphoma Myeloma Leukemia Subclavian vein Internal jugular vein 63 (55%) 14.8 t- 4.5 23.9 t- 12.8 24.8 t- 4.7 23.8 ? 3.6 12.5 % 1 34.3 t 8.2 7 (6%) 52 (45%) 14.3 ? 4.8 24.6 t- 15 23.8 ? 4.7 23.9 t 5.6 12.6 .c 1.1 32.9 ? 5.1 17 (15%) 5 8 1 43 7 8 2 41 pneumothoraces, hydromediastinum, or air embolism were also evaluated. Infection and catheter-related sepsis were not evaluated. Statistical analysis performed included chisquared and Student's t tests and logistic regression with P < 0.05 considered significant. All data are presented as mean 2 standard deviation. RESULTS 12 total of 115 catheters were inserted in 115 consecutive patients, 60 males (52%), and 55 females (48%). In five patients, catheters were unable to be placed. ,411 of the failed attempts were internal jugular sites. Four of these patients subsequently received a femoral and one a right subclavian line. Only the subclavian site was included in the final statistical analysis. Sixtythree (55%) subclaviar and 52 (45%) internal jugular catheters were placed. The internal jugular placement sites were divided as follows: right internal jugular vein, 40 (35%)and left internal jugular vein, 12 (10%). The subclavian sites were right subclavian vein, 52 (45%) and left subclavian vein, 11 (10%). The mean age of the patients was 49 -+ 16 years (range, 18- 100 years), 47 +- 14 years for the subclavian site cannulation and 52 t 19 years for the internal jugular site. All patients had a history of malignancy; 12 (10%) had a solid tumor, 16 (14%) lymphoma, 3 (2%) myeloma, and 84 (73%)leukemia (Table 1).Five (4%) had a previous history of neck surgery, 2 (1%) had chest surgery, and 1 (1%)patient had breast and axillary dissection. Three (2%) had previous neck radiation. Thirty-six of the patients had previously received a central line and 39 of the patients had other lines at the time of placement: 12 (31%)a right internal Subclavian Internal jugular Major Minor 0 7 16 1 jugular, 3 (8%) a left internal jugular, 12 (31%)a right subclavian, 11 (29%)a left subclavian, and 1 patient an external jugular line. Only 14 patients had a pulmonary catheter placed simultaneously. Thirty-six (31%)of the lines were placed for antibiotic therapy, 12 (10%)for chemotherapy, 45 (39%)for chemo/ antibiotic therapy, 14 (12%)for hemodynamic monitoring, and 8 (7%)for fluid administration. The pretransfusion platelet count was 14.6 -+ 4.7 x I09/L (range, 3-20 x 10g/L),with a posttransfusion platelet count of 24.3 -C 13.8 x log/ L (range, 2-73 x 109/L). The posttransfusion platelet count was considered as the procedure count. A median of 6 units of platelets were transfused for 107 catheterizations resulting in an increase in the platelet count of 9.61 i 13.2 x 109/L.Eight patients did not receive transfusions for the procedure. There were no reported complications related to platelet transfusions. Prolonged PT and PTT were observed in 8 patients (7%)' 4 of whom (3%) received fresh frozen plasma transfusions prior to venipuncture. In these four selected cases, the decision to attempt to reverse the underlying coagulopathy by means of a fresh frozen plasma transfusion was based on the antecedent clinical evidence of increased bleeding tendency. Posttransfusion PT and PTT were not reported. Total major and minor complications numbered 24 (21%) (Table 2 ) . Twenty-three patients had minor complications and only 1pneumothorax was reported. Failed attempts were not included as a complication but follow-up chest X-rays were done and the patients were evaluated at 24 hours. Seven of the minor complications (6%) occurred in association with subclavian cannulation (4 oozing, 2 hematomas, and 1 oozing and hematoma). Cannulation of internal jugular veins was associated with a higher incidence of minor complications (n = 17; 15%) ( P = 0.005). Sixteen instances of oozing/hematoma and 1 pneumothorax occurred. Seven patients with minor complications were transfused a mean of 8 i 4.8 (range, 4-18) additional units of platelets. Oozing was minimal and was relieved with local pressure, and small hematomas resolved within 24 hours, neither necessitating blood transfusions. The 24 patients with complications had platelet transfusions. Among the 23 patients with oozing and/or he- 2028 CANCER November 1,1996 / Volume 78 / Number 9 matoma, 19 had a normal coagulation pattern, whereas the remaining 4 patients had elevated PT and PTT. Those four patients experienced minor complications: one in the internal jugular vein and three in the subclavian vein. The other four patients with abnormal coagulopathy had no complications and required no fresh frozen plasma transfusions. The mean pretransfusion platelet count associated with oozing and/ or hematoma was 14.8 ? 4.9 x 109/L (range, 6-20 x 109/L), and was 14.6 2 4.6 x 109/L (range, 3-20 x 109/L) in patients with no complications. The mean posttransfusion platelet count in patients with no complications was 23.9 c 13.2 x 109/L (range, 2-73 x 109/L).The mean posttransfusion platelet count in patients with complications was 25.5 2 15.9 x 109/L (range, 2-59 x 109/L).There were only 3 patients with a platelet count above 50 x 109/L in the group with complications and 4 in the group without complications. In patients with no complications (n = 91; 79%), successful cannulation was achieved with 1.2 2 0.5 attempts, whereas in patients experiencing complications (n = 24; 21%), 1.6 -c_ 1 attempts occurred. Patients experiencing more than one attempt had more complications ( P = 0.003). There was no correlation between site and number of attempts. The catheter tip was reported in the superior vena cava in 82 of the cases (73%), in the right atrium in 6 (5%), and in the junction of the superior vena cava and right atrium in 13 (12%).There was no statistical difference between the site, history of previous venous cannulation, or concomitant presence of other lines and the number of attempts. In the eight patients with a prior history of neck surgery or radiation, there was no impact on outcome. The relationship between the complications and prognostic factors site, and attempt was analyzed by a logistic regression model. A relative risk of 4 (95% confidence interval [CI], 1.46- 10.31) of minor complications for internal jugular versus subclavian sites was found, i.e., the internal jugular site was 4 times more likely to cause complications than the subclavian site. Similarly, a relative risk of 4.3 (95% CI, 1.57-11.67) was found for > 1 versus 1 attempt. After adjusting for attempts, a relative risk of 4.6 (95% CI, 1.62-13.42) was found for internal jugular versus subclavian sites. Controlling for site, a relative risk of 5.5 (95%CI, 1.7615.69) was found for 2 1 attempts versus 1 attempt. Age and malignancy were not found to be significantly associated with the outcome variable (Table 3). DISCUSSION Approximately 3 million central venous catheters are inserted annually in the U.S.*O These procedures are associated with significant complications that are re- TABLE 3 Logistic Regression Analysis and Odds Ratio of Internal Jugular Compared with Subclavian Line Odds ratio (95% CI) IJ vs. SC Number of attempts Univariate (unadjusted) Multivariate (adjusted] 4 (1.46-10.31) 4.3 (1.57-11.67) 4.6 (1.62-13.42) 5.5 (1.76-15.69) CI:confidence interval: IT: internal iurmlar: S C subclavian lated to physiologic, anatomic, or pathologic factors, device malfunction or failure, or the experience of the health care professional. Scott” reported that 52% of complications and 62% of deaths were related to the experience of the health care professional, whereas device failure contributed to 12% of complications. Various reports have estimated that complications occur in 5-20% of procedures.’2,21,22 Boyd et a1.’ reported that hematomas (small to moderate) were present in 2.8%of cases. In 1989, the Food and Drug Administration task force issued recommendations to minimize such complications, stating that central venous catheterization should be performed only when the benefits appear to outweigh the inherent risks of the procedure, and must be performed only by trained personnel well versed with the anatomic landmarks, safe techniques, and potential complications.20 Thrombocytopenia is associated with an increased risk of bleeding complications and can be a life-threatening condition. Thrombocytopenia is a common occurrence in intensive care units and in cancer patients, usually due to underlying disease, sepsis, and antineoplastic chemotherapy as independent risk factors, and is associated with an increased mortality.23Management of thrombocytopenia must be individualized, with a platelet count of <20 x lo9/ L commonly used as the level at which to consider t r a n s f ~ s i o n sThrombocytopenic .~~ patients with platelet counts < 20 x 109/L are at an increased risk for bleeding, complicating invasive or surgical manipulations. Some investigators have reported a low rate of bleeding with line placement ranging from 0.22%.1,22,23 A study in coagulopathic liver transplant patients showed there was no bleeding complications with line placement despite the lack of attempts to correct hemostatic disorders.25 Bleeding complications occurred after central line placement in 0.5%of dialysis patients, after femoral insertion, the complication rate was 6% in patients with platelet counts > 20 x 109/L (4%).5-28In the current series of patients the surprising finding was that after platelet transfusions Central Line Placement in Profoundly Thrombocytopenic PatientslBarrera et al. there was little difference in posttransfusion platelet counts between those patients with complications and those without. The rate of complications in patients not receiving platelet transfusions was zero. At Memorial Sloan-Kettering Cancer Center, a comprehensive cancer treatment center, the etiology of thrombocytopenia is most commonly due to antineoplastic chemotherapeutic regimens, underlying neoplastic disorders, andlor sepsis. Adequate vascular access is essential for the administration of various therapeutic regimens. The indications for percutaneous short term central venous catheterization were mostly for the administration of multiple antibiotics, (chemotherapy, parenteral nutrition, and fluid management. The incidence of hemorrhagic complications ,are reported to be minimal with a near absence of severe or fatal hemorrhage at platelet counts > 10-20 x 109/L.15-16 Platelets were transfused for 107 procedures, resulting in an increase in the platelet count of 9.61 ? 13 x 109/L,which provided a posttransfusion platelet count of 24.25 2 13.79 X 109/L.A total of 24 complications (21%) occurred. A higher incidence of minor complications occurred during cannulation of the internal jugular vein (17) compared with the subclavian vein (7) (15%vs. 6%;P = 0.005). Minor complications occurred 50% more often with internal jugular vein cannulation, probably because it is a more observable site. Four patients requiring fresh frozen plasma transfusions had bleeding complications. Bleeding complications occurred only in 4 of 8 patients with abnormal coagulopathy, and a normal coagulation profile was evident in 19 of 23 patients with bleeding complications. One major complication, pneumothorax, was associated with an internal jugular venipuncture. Both internal jugular and subclavian veins are associated with the same success in cannulation rate. Thrombocytopenia is not an absolute contraindication for any procedure. Investigators had demonstrated the safety of bronchoscopy and thoracentesis in the presence of t h r o r n b o ~ y t o p e n i a .Even ~ ~ ~ ~in~ skilled hands, internal jugular catheterization is associated with a 2% risk for carotid artery perforation. Subclavian catheterization is associated with increased risks for pneumothorax of 2-5%,31-35and subclavian artery puncture of 0-3.8%.14Advantages of the subclavian site include relatively constant anatomy (with respect to the clavicle), greater physical stability of the catheter, and less tendency toward contamination than the internal jugular site. The detection of more complications at the internal jugular site could be due to its easier visualization in comparison with the subclavian site. The greater relative risk can be 2029 explained because the internal jugular site is less stable than the subclavian site due to soft tissue in the neck. In patients with no complications (91) cannulation was performed successfully with fewer attempts, in comparison with those with complications (79% vs. 21%). Successful cannulation with no complications was achieved with 1.2 i 0.5 attempts, which is equal to the number of punctures reported by Koski et a1?* None of the lines in the current study were placed using the ultrasound technique. The level of training and experience in line catheterization varied among the different inserters in the current study study, but due to extensive exposure at the study institution, they were considered qualified for line insertion of high risk procedures. Complications are minor if catheterization is performed or supervised by experienced personnel. CONCLUSION Central venous catheterization can be performed safely in thrombocytopenic patients with minimal complications if certain precautions are taken. The procedure should be performed by experienced personnel familiar with the anatomic landmarks. 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