The Role of Drains in Lumbar Spine Fusion

Transcription

1 The Role of Drains in Lumbar Spine Fusion Mohammad Sami Walid 1, Moataz Abbara 2, Abdullah Tolaymat 2, James R. Davis 3, Kevin D. Waits 3, Joe Sam Robinson III 3, Joe Sam Robinson Jr. 2 Key words Blood transfusion Drain Lumbar fusion Posthemorrhagic anemia Postoperative fever Wound infection Abbreviations and Acronyms ICD-9: International Classification of Diseases, 9th Edition IVPB: Intravenous piggyback LDF: Lumbar decompression and fusion From the 1 Georgia NeuroCenter, Medical Center of Central Georgia, Macon, Georgia; 2 Georgia Neurosurgical Institute, Macon, Georgia; and 3 Mercer University School of Medicine, Macon, Georgia, USA To whom correspondence should be addressed: Mohammad Sami Walid, Ph.D. [ mswalid@yahoo.com] Citation: World Neurosurg. (2012) 77, 3/4: DOI: /j.wneu Journal homepage: Available online: /$ - see front matter 2012 Elsevier Inc. All rights reserved. INTRODUCTION Postoperative surgical site infections (wound infections) can be quite complicated and a challenge to the treating physician. The literature reports the incidence of such infections ranging from 0.7% 16% of spinal surgery patients, with more occurring in instrumented fusions (3, 6). Reducing the number of such infections would help prevent extended hospital stay and reoperation and ultimately reduce the overall surgical stress. The U.S. Centers for Disease Control and Prevention estimated that 22% of all health care associated infections are surgical site infections and result in $1 10 billion annually in direct and indirect medical costs (1). Fever is also common in postoperative patients and does not always indicate infection (8). Although drains serve a valuable role to the patient, they are essentially foreign bodies that can promote infections at the wound site afterasurgicalprocedure. Theinsertionofthe OBJECTIVE: To study the role of drains in lumbar spine fusions. METHODS: The charts of 402 patients who underwent lumbar decompression and fusion (LDF) were retrospectively reviewed. Patients were classified per International Classification of Diseases, 9th Edition (ICD-9) procedure code as (lateral fusion, 74.9%) and (posterior fusion, 25.1%). The investigators studied the prevalence of drain use in lumbar fusion procedures and the impact of drain use on postoperative fever, wound infection, posthemorrhagic anemia, blood transfusion, and hospital cost. RESULTS: No significant differences in wound infection rates were noted between patients with and without drains (3.5% vs 2.6%, P 0.627). The difference in postoperative fever rates between patients with and without drains (63.2% vs 52.6%, P 0.05) was of borderline significance. Posthemorrhagic anemia was statistically more common in patients with drains (23.5% vs 7.7%, P 0.000). Allogeneic blood transfusion was also statistically more common in the drained group (23.9% vs 6.8%, P 0.000). Postoperative hemoglobin levels were lower in patients with drains who underwent one-level (9.5 g/dl vs 11.3 g/dl) or two-level (9.3 g/dl vs 10.2 g/dl) spine fusions. In this series in which drains were liberally used, no patient had to return to the operating room because of postoperative hematoma. An increased rate of allogeneic blood transfusion was noticed with posthemorrhagic anemia and drain use. The rate of allogeneic blood transfusion increased from 5.6% in patients without drains or posthemorrhagic anemia to 38.8% in patients with drains and posthemorrhagic anemia as a secondary diagnosis. The use of drains was associated with statistically insignificant increases in length of stay and cost in posterior procedures. Drain use was associated with shorter length of stay and hospital charges in lateral fusions of three or more levels. CONCLUSIONS: Drain use did not increase the risk of wound infection in patients undergoing LDF, but it had some impact on the prevalence of postoperative fever. Drain use was significantly associated with posthemorrhagic anemia and allogeneic blood transfusion. Drain use did not have a significant economic impact on hospital length of stay and charges except in lateral procedures involving three or more levels. drain incites a local inflammatory response, which leads to activation of neutrophils and other cells of the host defense system, and can act to spread infections inadvertently to neighboring sites of sterile tissue (5). The debate on whether to use drains in surgical patients continues (1). Many surgeons and infectious disease specialists believe that the use of a drain increases the risk of infection, which outweighs the purpose of using it (ie, decreasing hematoma risk and postoperative neurologic difficulties). In this study, a cohort of postoperative spinal surgery patients was analyzed to investigate the relationship between the use of a drain and the risk of fever, wound infection, or hematoma formation in patients undergoing lumbar fusion. METHODS In our institution, lumbar decompression and fusion (LDF) procedures are usually WORLD NEUROSURGERY, DOI: /j.wneu

2 Table 1. Classification of Studied Variables Clinical Variables Stratifying Variables Cost Variables Drain (yes/no) Lateral or posterior fusion Length of stay (days) Postoperative fever 100 F (yes/no) No. levels (1, 2, 3) Hospital charges ($) Wound infection (yes/no) Posthemorrhagic anemia as a second diagnosis per ICD-9 code (yes/no) Postoperative blood transfusion Postoperative hemoglobin (scale variable) Return to OR because of hematoma (yes/no) ICD-9, International Classification of Diseases, 9th Edition; OR, operating room. performed by a neurosurgeon and an orthopedic surgeon, and a Jackson-Pratt closedsuction drain is habitually installed at the end of the procedure to decrease the risk of hematoma formation and neurologic compromise. In this study, the charts of 402 patients undergoing LDF operated between October 2007 and September 2009 were retrospectively reviewed. Patients were classified per International Classification of Diseases, 9th Edition (ICD-9) procedure code as (lateral fusion, 74.9%) and (posterior fusion, 25.1%): y Lateral transverse process technique y Arthrodesis of lumbar or lumbosacral region a. Posterior (interbody) technique b. Posterolateral technique 2. Posterior lumbar interbody fusion 3. Transforaminal lumbar interbody fusion Postoperative temperature threshold was 100 F (37.7 C). Wound infection was determined by hospital course and follow-up. Posthemorrhagic anemia was extracted from the ICD-9 secondary diagnosis codes. Hospital charges were used as reflective of hospital cost. 2, Student t, and Wilcoxon- Mann-Whitney tests were used in statistical analysis of studied variables (Table 1). All patients received infection prophylaxis using the following protocol: y Patients weighing 80 kg: cefazolin 1 g intravenous piggyback (IVPB) y Patients weighing 80 kg: cefazolin 2 g IVPB y Patients with cefazolin allergy: vancomycin 15 mg/kg IVPB over 1 hour Postoperative fever and pain management protocol was as follows: y For temperature 101 F (38.3 C), incentive spirometry 10 times per hour y For temperature F (38.6 C), acetaminophen (Tylenol) 650 mg every 4 hours orally or per rectum y For temperature 102 F ( 38.9 C), draw blood for culture 2, sputum culture, Gram stain, urinalysis and culture and stain, cooling blanket if not brought down by acetaminophen y For pain, patient-controlled analgesia or oral narcotic analgesic (Lortab 5/500) as needed Limitations This study is based on hospital administrative data, which are coded using the ICD-9 system. These codes may not differentiate minimally invasive from open lumbar fusion cases. Estimated blood loss, recorded in anesthesia or surgery records, was not collected in thisstudy; instead, postoperativehemoglobin and secondary ICD-9 diagnosis of posthemorrhagic anemia were used. This choice may have caused a selection bias. RESULTS Demographic Characteristics and Comorbidities The patient cohort comprised 57.0% women and 43% men. The mean age was 57.3 years Table 2. Cross-Tabulation of Diagnosis Codes versus Procedure Codes and Number of Levels Principal Procedure Lumbar/Lumbosacral Fusion Lateral Lumbar/Lumbosacral Fusion Posterior Principal Diagnosis 1 Level 2 Levels >3 Levels 1 Level 2 Levels >3 Levels Lumbosacral spondylosis Lumbar disc displacement Lumbar/lumbosacral disc degeneration Lumbar disc disease with myelopathy Spinal stenosis lumbar Acquired spondylolisthesis Spondylolisthesis WORLD NEUROSURGERY 77 [3/4]: , MARCH/APRIL

3 y 0.0% returned to operating room because of hematoma Figure 1. Rates of postoperative (PostOp) fever, wound infection, posthemorrhagic (PostHem) anemia, and allogeneic blood transfusion per drain use. (standard deviation 11.5 years), and the mean body mass index was 31.3 kg/m 2 (standard deviation 6.8 kg/m 2 ). Diabetes mellitus was present in 29.1% of patients. Diagnosis Codes, Procedure Codes, and Number of Levels One-level (n 37) and two-level (n 48) lumbar/lumbosacral lateral fusions performed for lumbar disk displacement were the most common cases (Table 2). Prevalence of Outcome Variables The prevalence of outcome variables was as follows: y 70.9% of patient had drains y 60.1% had postoperative fever y 3.2% had wound infection y 18.9% had posthemorrhagic anemia y 18.9% had allogeneic blood transfusion No significant differences in wound infection rates were noted between patients with and without drains (3.5% vs 2.6%, P 0.627, Figure 1). The difference in postoperative fever rates between patients with and without drains (63.2% vs 52.6%, P 0.05) was of borderline significance. In diabetic patients, drains were associated with a statistically insignificant increase in infection rate (7.1% vs 3.0%, P 0.05). Posthemorrhagic anemia was statistically more common in the group with drains (23.5% vs 7.7%, P 0.000). Allogeneic blood transfusion was also statistically more common in the drained group (23.9% vs 6.8%, P 0.000), especially with fewer operated levels (Figure 2). Postoperative hemoglobin levels were lower in patients with drains who underwent one-level (9.5 g/dl vs 11.3 g/dl) or two-level (9.3 g/dl vs 10.2 g/dl) spine fusions. In a model including obesity, type of procedure, age, gender, number of levels, drain use, and blood transfusion, drain use and number of levels were significant predictors (P 0.01) of posthemorrhagic anemia and allogeneic blood transfusion. Drain use was not a significant predictor of postoperative fever or wound infection. An increased rate of allogeneic blood transfusion was noticed with posthemorrhagic anemia and drain Figure 2. Rates of posthemorrhagic (PostHem) anemia and allogeneic blood transfusion per type of procedure, number of levels, and drain use WORLD NEUROSURGERY, DOI: /j.wneu

4 in lateral fusions involving three or more levels (Figure 4). Figure 3. Rates of blood transfusion (Cell Saver or allogeneic [Allo Blood]). PH, posthemorrhagic. use. The rate of allogeneic blood transfusion increased from 5.6% in patients without drains or posthemorrhagic anemia to 38.8% in patients with drains and posthemorrhagic anemia as a secondary diagnosis (Figure 3). Economic Impact of Drain Use The use of drains was associated with a statistically insignificant increase in length of stay and cost in posterior procedures. In contrast, drain use was associated with shorter length of stay and hospital charges DISCUSSION Our study has several limitations inherent to anyretrospectivestudy. Notallvariablescould be normalized in regard to intraoperative factors and comorbidities other than obesity and diabetes (3, 6). Nevertheless, this investigation generated several useful findings. On the positive side of drain use, there was no return to the operating room because of neurologic compromise related to postoperative bleeding, a finding that supports the use of drains in lumbar fusions. Also, the liberal use of drains was not associated with an increased risk of wound infection. This finding seems to be consistent with the findings of other researchers such as Payne et al. (4), who conducted a study on closed suction drainage after single-level lumbar laminectomy and found no significant difference in the rate of infection or wound healing between patients with and without drainage, and no patient developed postoperative neurologic deficit. Scuderi et al. (7) studied drain use after lumbar fusions at a single level for degenerative disease and concluded that drains do not appear to increase the risks of wound related complications. More recently, Kanayama et al. (2) showed that the risk of wound infection and hematomas in single-level lumbar decompression surgery was not influenced by use of a drain. From an economic point of view, drain use did not significantly increase hospital charges or length of stay. On the negative side of drain use, we found an increased prevalence of postoperative fever associated with drain use, which could be a reaction to the invasiveness of surgery and the nature of drains as a foreign body. Drain use was associated with a significant increase in blood transfusion requirements. There was no way to know if drains have a role in impairing the coagulation cascade and preventing wound tamponade or whether drains are more willingly used in cases with excessive intraoperative bleeding. Because our study was retrospective, the rationale behind the decision to use a drain in each case was unknown. Figure 4. Length of stay and hospital charges per drain use in lateral and posterior single-level and multiple-level fusion procedures. CONCLUSIONS To resolve these contradictory results, we recommend larger prospective controlled WORLD NEUROSURGERY 77 [3/4]: , MARCH/APRIL

5 studies in which drains are employed in a random fashion with the caveat that a surgeon may opt to remove a patient from the study and insert a drain if the surgeon believes the hemostatic status of the patient warrants this maneuver. Until such data become available, the use of drains will be based on individual surgical judgment. REFERENCES 1. American Academy of Orthopaedic Surgeons Patient Safety Committee, Evans RP, Huddleston PM, Clyburn TA, Evans RP, Moucha CS, Prokuski LJ, Joseph J, Sale K: Surgical site infection prevention and control: an emerging paradigm. J Bone Joint Surg Am 91(Suppl 6):2-9, Kanayama M, Oha F, Togawa D, Shigenobu K, Hashimoto T: Is closed-suction drainage necessary for single-level lumbar decompression? Review of 560 cases. Clin Orthop Relat Res 468: , O Toole JE, Eichholz KM, Fessler RG: Surgical site infection rates after minimally invasive spinal surgery. J Neurosurg 11: , Payne DH, Fischgrund JS, Herkowitz HN, Barry RL, Kurz LT, Montgomery DM: Efficacy of closed wound suction drainage after single-level lumbar laminectomy. J Spinal Disord 9: , Rotstein OD, Brisseau GF: (1995). The microenvironment of infection: adjuvants in surgical infection. In: Fry DE, ed. Surgical Infections. Boston: Little Brown; 1995: Schimmel JJ, Horsting PP, de Kleuver M, Wonders G, van Limbeek J: Risk factors for deep surgical site infections after spinal fusion. Eur Spine J 19: , Scuderi GJ, Brusovanik GV, Fitzhenry LN, Vaccaro AR: Is wound drainage necessary after lumbar spinal fusion surgery? Med Sci Monit 11:CR64-CR66, Walid MS, Woodall MN, Nutter JP, Ajjan M, Robinson JS Jr: Causes and risk factors for postoperative fever in spine surgery patients. South Med J 102: , Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. received 08 December 2010; accepted 27 May 2011 Citation: World Neurosurg. (2012) 77, 3/4: DOI: /j.wneu Journal homepage: Available online: /$ - see front matter 2012 Elsevier Inc. All rights reserved WORLD NEUROSURGERY, DOI: /j.wneu