Bacterial growth on suction drain tips. Prospective study of 489 clean orthopedic operations

Examining the Efficacy of Drain Tip Cultures in Predicting Postoperative Surgical Site Infections in Hip Arthroplasty: A 15-Year Retrospective Study

Background Postoperative surgical site infections (SSIs) are a significant complication of surgical procedures, leading to increased morbidity, prolonged hospital stays, and substantial healthcare costs; however, the use of drain tip cultures to diagnose SSIs in patients is controversial. The objective of this study was to evaluate the efficacy of drain tip cultures for the prediction of postoperative SSIs in patients recovering from hip arthroplasty. Methodology The data were collected from 1204 patients who underwent hip arthroplasty procedures over 15 years, and statistical analysis was performed to evaluate the diagnostic value of drain tip culture in determining surgical site infection. We also used these data to evaluate whether preexisting conditions such as hypertension or diabetes affected the probability of a patient getting an SSI. Results Drain tip cultures were positive in 12 of 1,112 cases of primary hip arthroplasty, but only one of these 12 patients was ultimately diagnosed with an SSI (sensitivity, 12.5%; specificity, 99.0%; p = 0.0834). Results from postoperative drain tip cultures performed in patients undergoing revision arthroplasty included two false positives and three false negatives; interestingly, no true positives were detected in any of the revision arthroplasty cases we evaluated (sensitivity, 0％; specificity, 97.8％; p = 0.9355). Conclusion Our results indicate that drain tip cultures have no statistically significant predictive value for the diagnosis of postoperative SSIs and thus should not be used as a primary diagnostic or predictive tool for SSIs. We recommend exploring other diagnostic tools for the postoperative diagnosis of SSIs. Standardized guidelines should therefore be established to improve the predictive value of the different methods.

Routine Use of Closed Suction Drains Following Revision Arthroplasty May Not be Necessary

BACKGROUND

There are numerous studies demonstrating that closed suction drainage (CSD) usage after primary total joint arthroplasty (TJA) has little to no benefit. There are little data on the role of CSDs after revision TJA. The purpose of our study was to evaluate whether there is any clinical advantage to CSD usage after revision TJA.

METHODS

This retrospective study evaluated the clinical records of 2,030 patients undergoing revision TJA between 2007 and 2021. CSD was used in 472 patients and not used in 1,558 patients. Primary outcome was blood transfusion rate and secondary outcomes included total blood loss (TBL), as determined by Gross formula, wound complications (hematoma, infection, and dehiscence), and length of hospital stay. Patients undergoing revision TJA for oncologic reasons or those with incomplete datasets were excluded.

RESULTS

There were no statistically significant differences in rates of allogeneic blood transfusion, TBL, and wound complications (hematoma, infection, and dehiscence) between the two groups (P = .159, .983, .192, .334, and .548, respectively). When adjusted for demographic and surgical confounders, there was no difference in transfusion and TBL rates between groups (Odds Ratio 1.04, 95% Confidence Interval 0.78-1.38, P = .780 and estimate -105.71 mL, 95% confidence interval -333.96 to 122.55, P = .364, respectively). CSD cohort had a shorter length of stay (4.30 versus 5.82 days, P < .001).

CONCLUSION

We acknowledge that there is a role for CSD usage in a selected group of patients. Nevertheless, our study revealed that routine use of CSD after revision TJA does not provide an additional clinical benefit.

Suction drainage fluid culture during septic orthopaedic surgery, a retrospective study

We evaluated the usefulness of suction drainage fluid culture after septic orthopaedic surgery to predict early surgical reintervention. We conducted a retrospective observational study, at the Groupe Hospitalier Paris Saint-Joseph between 2014 and 2019. All the patients undergoing septic orthopaedic surgery, with perioperative samples and a postoperative suction drainage device, were enrolled. We compared the group with positive or negative postoperative drainage fluid cultures, respectively, on surgical outcome. We included 246 patients. The drainage fluid culture was positive in 42.3% of the cases. Early surgical reintervention concerned 14.6% of the cases (n = 36), including 61.1% of patients with positive drainage fluid culture (n = 22/36). The risk factors associated with positive drainage fluid cultures were the debridement of the infected site (without orthopaedic device removal), an infection located at the spine, perioperative positive cultures to Staphylococcus aureus. The complete change of the orthopaedic device, and coagulase-negative staphylococci on the preoperative samples, was associated with negative drainage fluid cultures. Positive drainage fluid culture was predictive of early surgical reintervention, and coagulase-negative staphylococci in the preoperative samples and knee infection were predictive of surgical success. Postoperative drainage fluid cultures were predictive of early surgical reintervention. Randomized multicentric studies should be further conducted.

Do tourniquet and drainage influence fast track in total knee arthroplasty? Our results on 151 cases

Background: Fast track in total knee replacement (TKR) is a widely used protocol. Tranexamic acid proved to be effective in reducing perioperative bleeding without increasing thromboembolic risk. The aim of this study was to assess if tourniquet and suction drainage might affect perioperative blood loss and post-operative functional recovery after TKR. Methods: 151 patients, who underwent to TKR, were assessed and divided into three homogeneous groups: group A (51 patients) in which both tourniquet and suction drainage have been applied (tourniquet has been release before wound closure); group B (50 patients) in which neither tourniquet nor suction drainage have been used; group C (50 patients) in which only tourniquet has been used. Perioperative intravenous tranexamic acid and post-operative low-molecular-weight heparin have been administered. Trend of haemoglobin values, transfusion rate, pain, ability to obtain 90 degrees of flexion and length of stay were analysed. Results: The average intra-operative blood loss was statistically higher in group B in comparison to other two groups. Haemoglobin values were lower in group A in comparison to group C in the third and fifth post-operative days. Patients in group A had higher transfusion rate, higher pain and had more difficulties in reaching a 90 degrees of knee flexion than the other two groups. There was one infection in group A. No differences in length of stay. Conclusion: Suction drain seems to be associated to lower haemoglobin values, higher transfusion rate, higher pain and slower functional recovery. Short-term tourniquet does not influence post-operative bleeding and rehabilitation program. (www.actabiomedica.it)

Methicillin-Resistant Staphylococcus aureus Nasal Swab and Suction Drain Tip Cultures in 4573 Spinal Surgeries: Efficacy in Management of Surgical Site Infections

STUDY DESIGN

A retrospective single-center study.

OBJECTIVE

To assess the diagnostic value of methicillin-resistant Staphylococcus aureus (MRSA) nasal swab and suction drain tip cultures.

SUMMARY OF BACKGROUND DATA

The prognostic value of MRSA nasal swab and suction drain tip cultures has not been firmly established in spinal surgery.

METHODS

This study retrospectively included 4573 consecutive patients who underwent spinal surgery between January 2008 and December 2014. Patients diagnosed with infectious disease were excluded. Prophylactic antibiotics were administered intraoperatively and postoperatively for 48 hours. MRSA nasal swab cultures were taken from all patients before surgery. Drains were removed when the volume of postoperative fluid drainage was less than 50 mL in the preceding 24 hours and cultures were made. Surgical site infection (SSI) was defined according to Centers for Disease Control and Prevention criteria.

RESULTS

SSI was identified in 94 cases (2.1%) and bacteria were isolated in 87 cases (92.6%). Positive MRSA nasal swab cultures were identified in 49 cases (1.1%). There was no significant difference in the SSI positivity rate between the MRSA nasal swab culture (+) and (-) groups. Positive drain tip cultures were found in 382 cases (8.4%), 28 of which developed SSI. There was a significant difference in the SSI positivity rate between the drain tip culture (+) and (-) groups. The sensitivity of drain tip culture was 29.8% and the specificity was 92.1%. In 16 of the 28 patients in the SSI (+) group with positive drain cultures, the same bacteria were isolated from the surgical site, giving a bacteria matching rate of 57.1%.

CONCLUSION

MRSA nasal swab and drain tip cultures were not useful for predicting SSI. However, drain tip culture had a high positivity rate in the SSI group and the coincidence rate for the causative pathogen was relatively high.

LEVEL OF EVIDENCE

4.

Prediction of surgical site infection in spine surgery from tests of nasal MRSA colonization and drain tip culture

PURPOSE

MRSA is an organism that is a possible risk factor for postoperative SSI. The purpose of the study was to examine relationships among surgical site infection (SSI) after spinal surgery, nasal methicillin-resistant staphylococcus aureus (MRSA) colonization, and wound drain culture results.

METHODS

The subjects were 132 patients who underwent spinal instrumentation surgery. A preoperative nasal swab was used to check for the presence of MRSA colonization, and a wound drain tip culture was performed for detection of SSI. Data from culture studies using nasal samples and those from the distal tip of the wound drain were used for analysis.

RESULTS

Five patients (3.8%) had nasal MRSA, 17 (13%) had positive drain tip cultures, 15 (11%) had SSIs, and 10 (8%) had SSIs with MRSA. Patients with nasal MRSA had a higher rate of detection of bacteria in the drain tip culture (40 vs. 19%, p = 0.065), and the SSI rate was significantly higher in patients with a positive drain tip culture (33 vs. 10%, p = 0.012). The total SSI rate differed significantly between patients with and without nasal MRSA (40 vs. 10%, p = 0.039); however, the SSI with MRSA rate did not differ significantly between these groups.

CONCLUSION

MRSA carriers were not necessarily associated with MRSA infection, but were related to a positive drain tip culture and SSI, which might be due to endogenous skin bacteria. Therefore, possible SSI should be considered in patients with nasal MRSA colonization or bacteria detected in a drain tip culture.

Use of closed suction drainage after primary total hip arthroplasty: a prospective randomized controlled trial

Objective

This study aimed to investigate drain use in a controlled population of patients with hip osteoarthritis undergoing primary total hip arthroplasty.

Methods

This prospective controlled trial evaluated 93 patients randomized into two groups: a group that received drains and a group that did not. The patients who were randomized to the drain group used a 3.2 mm drain placed under the fascia that was kept in place for 24 h. Postoperative evaluations were performed after 24 h and then three, six, and 12 weeks after total hip arthroplasty. The primary outcome was perioperative blood loss in both groups 24 h after total hip arthroplasty. The other parameters that were evaluated included mid-thigh circumference, the rate of blood transfusion, hematocrit, inflammatory serum levels, and the Harris Hip Score.

Results

The clinical and laboratory data revealed no differences between the study groups with respect to blood loss and need for blood transfusion, duration of hospital stay, reoperation rate, complications, inflammatory serum markers, and the Harris Hip Score. Patients without closed suction drainage reported higher pain levels after 24 h (VAS score 1 vs. 2, p < 0.01).

Conclusion

Similar clinical and laboratory outcomes were found in both cohorts.

Is a Drain Tip Culture Required After Spinal Surgery?

STUDY DESIGN

The efficacy of use of a drain tip culture for early detection of surgical-site infection (SSI) was investigated in 329 patients after spinal surgery.

OBJECTIVE

To examine the efficacy of a wound drain tip culture for detection of SSI in spinal surgery.

SUMMARY OF BACKGROUND DATA

A complication of SSI after spinal surgery has high associated morbidity and mortality, and is often difficult to treat.

MATERIALS AND METHODS

The subjects were patients who underwent spinal surgery at our institution between January 2010 and March 2013. All subjects were treated with antimicrobial prophylaxis based on evidence-based guidelines and were followed for at least 6 months after surgery. Data from culture studies using the distal tip of the wound drain were used for analysis.

RESULTS

Drain tip cultures were positive in 34 cases and there were 19 SSIs. Ten of the 34-tip culture-positive wounds developed SSI. Drain tip cultures had a sensitivity of 52%, specificity of 92%, positive predictive value (PPV) of 29%, and negative predictive value of 97% for predicting a wound infection. The association between a positive suction tip culture and wound infection was significant (P<0.05). The PPV for SSI was 60% in cases in which methicillin-resistant bacteria were detected in a drain tip, and the SSI rate in these cases differed significantly compared with those with non-methicillin-resistant bacteria (P=0.01).

CONCLUSIONS

A drain tip culture is useful for early detection of SSI caused by methicillin-resistant bacteria.

Drain Tip Culture is Not Prognostic for Surgical Site Infection in Spinal Surgery Under Prophylactic Use of Antibiotics

STUDY DESIGN

A retrospective observational study.

OBJECTIVE

We evaluated the prognostic value of drain tip culture performed for surgical site infection (SSI) after spinal surgery with a large number of subjects, and investigated whether the type of surgery or timing of drain removal correlated with positive drain culture and SSI rates.

SUMMARY OF BACKGROUND DATA

In many institutions, routine culture of suction drain tips that are placed in the surgical site of spinal surgeries has been performed to detect contamination after removal. However, few reports have evaluated whether drain tip culture is prognostic for SSI after spinal surgery.

METHODS

A total of 1240 suction drain tips that had been used in spinal surgeries were cultured after removal. Prophylactic antibiotics were administered during and after the surgery for 48 hours. We evaluated the correlation between the results of positive drain tip culture, SSI, and drain removal timing.

RESULTS

Positive drain tip cultures were found in 55 cases (4.4%). True SSI was identified in 18 cases (1.5%). The most frequently isolated microorganism in the both cases was Staphylococcus. The sensitivity of drain tip culture for SSI after spinal surgery was calculated as 0% according to the concordance rate between bacteria isolated in drain tip culture and SSI cases. There was no correlation between the duration of suction drainage and the drain tip culture results or the onset of SSI within 72 hours. The results of suction drain tip culture could not reflect those of SSI regardless of the type of surgery (primary or revision), surgical region, surgical procedure, or implant use.

CONCLUSION

Drain tip culture in spinal surgery was not prognostic for SSI or helpful in detecting pathogenic bacteria for SSI. Routine use of drain tip culture when prophylactic antibiotics are used is not supported by the results of this study.

LEVEL OF EVIDENCE

4.

Is Surgical Drain Useful for Lumbar Disc Surgery?

Objective

Surgical drains are commonly used after the spine surgeries for minimizing hematoma formation, which can delay wound healing and may become a source of fibrosis, infection, and pain. The drain, however, may provide a direct route for infection if it is contaminated. Our objective was to survey the relationship between surgical drains and infection.

Methods

The 70 patients who had undergone single-level lumbar discectomy from April 2011 to March 2012 were retrospectively analyzed. Each patient's medical chart and magnetic resonance image were thoroughly reviewed after all the patients had been divided into the drainage and the nondrainage groups. The amounts and durations of the surgical drains in the drainage group were analyzed. Additionally, the levels of C-reactive protein, rates of infection, scores of preoperative and postoperative visual analog scale (VAS), and lengths of hospital stay after operation were compared between the 2 groups.

Results

In this study, 70 patients were retrospectively analyzed; out of which, 42 and 28 patients were included in the drainage and the nondrainage groups, respectively. Two of the postoperative infection cases in the nondrainage group required to undergo repeated operations. The frequency of the postoperative infection cases was higher in the nondrainage group than in the drainage group; however, there was no significant statistical difference between the 2 groups (p=0.157).

Conclusion

Surgical drains did not elevate postoperative infection. Furthermore, drain tip cultures allowed us to detect postoperative infection at an early stage, and it led to faster initiation of antibiotics treatment.

Suction Drain Tip Culture after Spine Surgery: Can It Predict a Surgical Site Infection?

Study Design

Retrospective clinical study.

Purpose

To assess the diagnostic value of suction drain tip culture in patients undergoing primary posterior spine surgery.

Overview of Literature

To date, the diagnostic value of suction drain tip culture for predicting surgical site infection (SSI) has not been firmly established in orthopedic or spinal surgery.

Methods

In total, 133 patients who underwent primary posterior spine surgery from January 2013 to April 2015 were included in this retrospective study. Patients diagnosed with infective disease or condition was excluded. The suction drain tip was cut off approximately 5 cm from its far end. The sample was sent to the microbiological laboratory of the hospital for culture analysis. Any signs of infection, such as wound discharge or dehiscence, fever, chills, or chronic pain, were recorded. The culture outcome, identification of bacteria, and postoperative transition of the serum C-reactive protein level were also recorded in all patients. The wounds were followed up for a minimum of 3 months.

Results

A positive drain tip culture was found in 48 patients (36.1%), of whom, 6 developed SSI. The sensitivity of drain tip culture for SSI after primary posterior spine surgery was 60.0%, and the specificity was 65.9%. The association between the incidence of positive suction tip culture and SSI was not statistically significant. Among the 48 positive drain tip cultures, there was no significant association between the occurrence of SSI and virulence of isolated bacteria. There was no significant association between drain tip culture positivity and the duration of drainage, or between the rate of SSI and duration of drainage.

Conclusions

Suction drain tip culture analysis is a poor predictor of SSI after primary posterior spine surgery. Routine use of a drain tip culture is not supported by the results of this study.

Is Drain Tip Culture Prognostic of Surgical Site Infection? Results of 1380 Drain Tip Cultures in Total Hip Arthroplasty

The purpose of this study was to evaluate a prognostic value of drain tip culture for surgical site infection (SSI) after total hip arthroplasty. A total of 1380 closed suction drain tips cultured after removal in primary total hip arthroplasty were included in this study. Drains were removed in 12-72 hours after surgery. Drain tip cultures were positive in 11 cases (0.8%). SSI was found in 4 cases (0.3%), where the drain tip cultures were all negative. The sensitivity of drain tip culture for infection after surgery was 0%, and the specificity was 99.7%. We concluded that, drain tip culture cannot be prognostic for SSI after total hip arthroplasty. Routine use of drain tip culture is not supported.

Retained Surgical Drain After Total Knee Arthroplasty: An Eight-Year Follow-up: A Case Report

CASE

This report describes a patient in whom the intra-articular portion of a suction drain broke during total knee arthroplasty. The broken portion of the drain could not be removed, but the patient experienced no major complications over an eight-year follow-up period.

CONCLUSION

The presence of a retained surgical drain needs to be carefully assessed but is not an absolute indication for removal.

Risk factors of surgical site infections after supratentorial elective surgery: a focus on the efficacy of the wound-drain-tip culture

BACKGROUND

Surgical site infection (SSI) is one of the most dangerous complications after neurological surgery and is related to additional postoperative hospital days and an increased risk of death. One method for the early detection of SSI, the wound-drain-tip culture (WDC), has been widely used. However, no investigations on the relation between SSIs and wound drains after neurological surgery have been conducted. We performed this study to identify the risk factors for SSIs and to assess the relationship between SSIs and the results of WDC after elective supratentorial craniotomy.

METHODS

A total of 535 patients underwent elective primary supratentorial craniotomy, and the results of their WDC were analyzed. The mean follow-up period was 14.1 ± 12.2 months. In 347 (64.9 %) patients, the wound drain was removed within 2 days after operation.

RESULTS

Until follow-up, 14 (2.62 %) patients suffered from SSIs. Among the 21 patients with positive WDCs, 8 (38.1 %) patients experienced SSIs. The organisms cultured from the SSIs were matched with the WDC results in 7 (87.5 %) patients. In the multivariate analysis, underweight group (OR = 15.41, p = 0.002), maintenance wound drain over 3 days (OR = 4.202, p = 0.043), and positive WDC (OR = 36.67, p < 0.001) were significantly associated with postoperative SSIs. In 6 (85.7 %) of 7 patients with a positive WDC for Serratia marcescens, SSIs ultimately developed.

CONCLUSIONS

The prognostic value of the positive WDC still falls short of our expectations in the field of neurological surgery. And, the positive WDC results should be cautiously interpreted, considering the virulence of the cultured micro-organisms.

Closed suction drainage with or without re-transfusion of filtered shed blood does not offer advantages in primary non-cemented total hip replacement using a direct anterior approach

INTRODUCTION

Wondering if the use of drains allowing re-transfusion of shed blood as opposed to closed suction drains or no drains would improve quality of care to patients undergoing simple non-cemented primary total hip replacement (THR) using a direct anterior approach, a three-arm prospective randomized study was conducted.

METHOD

One hundred and twenty patients were prospectively randomized to receive no drain, closed suction drains or drains designed for re-transfusion of shed blood. Blood loss, VAS pain scores, thigh swelling, hematoma formation, number of dressings changed and hospital stay were compared and patients followed for 3 months.

RESULTS

Drains did not have any significance on postoperative haemoglobin and haematocrit levels or homologous blood transfusion rates. Patients receiving homologous blood transfusions had too small drain volumes to benefit from re-transfusion and patients, who get drained fluid re-transfused, were far away from being in need of homologous blood transfusion. Omitting drains resulted in more thigh swelling accompanied with a tendency of slightly more pain during the first postoperative day but without effect on clinical and radiological outcome at 3 months. Earlier dry operation sites resulting in simplified wound care and shorter hospital stay was encountered when no drain was used.

CONCLUSION

The possibility to re-transfuse drained blood was not an argument for using drains and, accepting more thigh swelling, we stop to use drains in simple non-cemented primary THR using the direct anterior approach.

Is there a benefit to drains with a Kocher-Langenbeck approach? A prospective randomized pilot study

BACKGROUND

Closed suction drainage is a routine part of wound management for patients undergoing surgical treatment of acetabulum fractures. This pilot study seeks to determine if there is a difference in wound healing for a Kocher-Langenbeck approach with and without the use of drains.

METHODS

We conducted a prospective, randomized study including 39 patients with acetabulum fractures treated through a Kocher-Langenbeck approach. During wound closure, patients were randomized into two groups: 20 patients (group I) received drains and 19 (group II) were closed without drains. All were followed up for drain output, quality and quantity of drainage, signs of infection, and duration of drainage. Patients were then evaluated at 2 weeks and 8 weeks for wound healing and any signs of infection.

RESULTS

By the 8-week follow-up, all wounds healed without any signs of infection. There was no difference in the average number of days of drainage between groups: 7.45 days and 7.95 days for group I and group II, respectively (p = 0.37). There were two wound complications (5.13%), with one in each group. Both complications consisted of cellulitis without signs of deep infection and had complete resolution with intravenous antibiotics. A post hoc power analysis determined that a test population of 1,264 patients would be needed to show a reduction in wound drainage time by 1 day.

CONCLUSION

With the numbers available in this pilot study, we showed no benefit to the use of drains for acetabular surgery performed through a Kocher-Langenbeck approach.

Comparison of drainage techniques on prolonged serous drainage after total hip arthroplasty

The aims of this study were to determine (1) whether the duration of closed suction drainage affects the occurrence and duration of prolonged serous drainage and (2) if closed suction drains could be omitted according to the wound and/or thigh appearance after unilateral primary total hip arthroplasty. One hundred thirty-nine patients undergoing total hip arthroplasty were randomized into 3 groups: 42 patients received no drainage, 46 patients received drainage for 24 hours, and 51 patients received drainage for 48 hours. No differences with respect to occurrence and duration of prolonged serous drainage were found between the 2 groups with drains. Although no prolonged serous drainage occurred, the swelling of the thigh was significantly greater (P < .001) and the occurrence of prolonged thigh pain was significantly higher (P = .01) in the group without drainage.

Prognostic value of suction drain tip culture in determining joint infection in primary and non-infected revision total hip arthroplasty: a prospective comparative study and review of the literature

INTRODUCTION

Closed suction drainage in joint replacement surgery has been considered to carry an obvious risk of bacteria invasion. Previous studies have shown controversial results regarding the role of suction drain culture in predicting artificial joint infection. Furthermore, the efficacy of the method has not been established in revision total hip or knee arthroplasty.

MATERIALS AND METHODS

Suction drain tips from 110 patients who underwent 73 primary and 37 revision non-infected total hip arthroplasties were prospectively cultured. The drains removed at 48 h postoperatively. The patients had an average age of 64.3 years (range 25-81 years) and followed up for 2-4 years (average 2.8 years).

RESULTS

Positive cultures were identified in two primary (2.74%) and six revision (16.22%) total hip replacements (p = 0.017). The most frequently isolated microorganisms were Staphylococcus aureus (3 cases) and S. epidermidis (2 cases). Resistance to perioperative antibiotics was found in three out of eight isolated pathogens. However, no infection was recorded in any of the eight patients whose cultures found positive.

CONCLUSION

Although suction drains are more often contaminated in revision total hip arthroplasty, the prognostic value of the method in determining joint infection is very limited and its routine use is not supported from the clinical data.

Suction drainage culture as a guide to effectively treat musculoskeletal infection

Following surgery for musculoskeletal infection, a positive suction drainage culture (SDC) is consistent with persistent sepsis. Our objective was to determine the effect of a negative SDC obtained in subsequent operations on the outcome of a musculoskeletal infection. 99 patients were prospectively enrolled, all treated surgically for musculoskeletal infection utilizing suction drainage and appropriate antimicrobial therapy. Surgery consisted of irrigation, debridement, and prosthetic exchange or implant removal. SDC was considered negative if all bottles resulted in negative cultures. Following SDC results, patients were placed into 1 of 2 treatment groups: 1) Negative SDC, and no new operation; or 2) Positive SDC, and new operation(s) until SDC was negative. Antibiotic therapy ranged from 6-12 weeks (osteomyelitis) to 10-21 d (soft tissue). Both groups were similar with regard to baseline characteristics. Cure was obtained in 91.8% of patients (56/61) in group 1 and 91.6% of patients (22/24) in group 2. Similar results were obtained in patients with an infection in the presence of an implant. In conclusion, a negative SDC following surgery for a musculoskeletal infection is a strong indication of eventual outcome.

Myths and legends in orthopaedic practice: are we all guilty?

Over years of practice, many beliefs and practices become entrenched as tried and tested, and we subconsciously believe they are based on scientific evidence. We identified nine such beliefs by interviewing orthopaedic surgeons in which studies (or lack thereof) apparently do not support such practices. These are: changing the scalpel blade after the skin incision to limit contamination; bending the patient's knee when applying a thigh tourniquet; bed rest for treatment of deep vein thrombosis; antibiotics in irrigation solution; routine use of hip precautions; routine use of antibiotics for the duration of wound drains; routine removal of hardware in children; correlation between operative time and infection; and not changing dressings on the floor before scrubbing. A survey of 186 practicing orthopaedic surgeons in academic and community settings was performed to assess their routine practice patterns. We present the results of the survey along with an in-depth literature review of these topics. Most surgeon practices are based on a combination of knowledge gained during training, reading the literature, and personal experience. The results of this survey hopefully will raise the awareness of the selected literature for common practices.

Infection associated with hematoma formation after shoulder arthroplasty

Hematoma formation requiring operative treatment after shoulder arthroplasty may be associated with higher patient morbidity. We therefore determined whether there was an association of hematoma formation requiring operative treatment with deep infection after shoulder arthroplasty. Between 1978 and 2006, we performed 4147 shoulder arthroplasties in 3643 patients. Of these, 12 shoulders (0.3%) underwent reoperation for hematoma formation. The mean time interval from arthroplasty to surgery for the hematoma was 7 days (range, 0.5-31 days). Among nine cases in which cultures were taken, six had positive cultures; the organisms included Propionibacterium acnes in three, Staphylococcus epidermidis in one, Streptococcus species in one, and Staphylococcus epidermidis with Peptostreptococcus in one. The minimum followup was 12 months (mean, 68 months; range, 12 to 294 months). Two of the 12 patients eventually underwent resection arthroplasty for deep infection. The Neer score was excellent in one, satisfactory in six, and unsatisfactory in five patients. The data suggest hematoma formation after shoulder arthroplasty is often accompanied by positive intraoperative cultures. The surgeon should be aware of the high rate of unsatisfactory results associated with this complication as well as the possibility of developing a deep infection requiring additional surgery.

LEVEL OF EVIDENCE

Level IV, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

Simplified wound care and earlier wound recovery without closed suction drainage in elective total hip arthroplasty. A prospective randomized trial in 100 operations

INTRODUCTION

Evidence to support or refute closed suction drainage (CSD) in primary total hip replacement (THR) is not conclusive. Our anecdotical experience was that persistent ooze from the drainage hole often delayed wound recovery. We hypothesized that, without CSD, wound care would be simplified without short or long term disadvantage.

MATERIALS AND METHODS

Hundred patients scheduled for primary THR were randomly assigned for CSD or non-drainage. Drains were withdrawn at day 2. Pain, wound hematoma, number of dressing changes, time of persistent discharge from the operation site (skin incision and drain hole), total blood loss and number of blood transfusions were prospectively recorded. Hip function, presence of heterotopic ossifications (HTO) and complications were recorded at a follow visit 1 year after surgery.

RESULTS

Wound sites managed without CSD needed significantly less wound dressings (P < 0.001) and were dry at an earlier time (P < 001). Despite a significant bigger subfascial hematoma in the non-drained group (P < 0.05), in terms of pain, thigh swelling, total blood loss, number of transfusions needed, hip function and HTO no difference was recorded between the groups (P = 0.2-0.82).

CONCLUSION

To omit CSD in primary THR results in simplified and more rapid wound management without any disadvantage at short and long term.

Drain clamping in knee arthroplasty, a randomized controlled trial

BACKGROUND

The purpose of this study was to determine whether repeated clamping of a suction drainage system will result in less external blood loss, blood transfusion and no increase in complications compared to a routine continuous suction drainage system. This was a randomized prospective study on patients undergoing total knee arthroplasty.

METHODS

Group A patients' drains were left clamped for all but 5 min (or 100 mL drainage) every 2 h for the first 6 h, then at 12-h and 24-h periods, when the drains were removed. Group B patients had continuous suction drainage. The amount of external blood loss, transfusion requirements and complications were compared between the two groups. The study group comprised 66 patients.

RESULTS

The mean external blood loss in the clamped drain group was 296.67 mL (standard deviation 160.28 mL) with a mean drain in situ time of 32 h, significantly less (P < 0.05) than the continuous drain group that had a mean external blood loss of 796 mL (standard deviation 250.34 mL) with a mean drain in situ time of 34 h. There was no difference in the requirements for transfusion between the two groups.

CONCLUSION

We conclude that clamping drains intermittently in hybrid total knee arthroplasty results in significantly less external blood loss with no change in morbidity or mortality. This study was a level 1 therapeutic study (i.e. with level of evidence randomized control trial with a significant difference).

High concentration and bioactivity of vancomycin and aztreonam eluted from Simplex cement spacers in two-stage revision of infected hip implants: a study of 46 patients at an average follow-up of 107 days

This study investigated the release of antibiotics in vivo, from an articulating polymethylmethacrylate (PMMA) spacer used in two-stage revision arthroplasty of infected hip implants. Forty-six patients who underwent two-stage revision hip arthroplasty for infections were managed with an interim PMMA spacer loaded with a high dose of vancomycin and aztreonam. Serum and aliquots of drainage collected after the first-stage surgery, and joint fluid obtained at the time of the second-stage surgery were analyzed for antibiotic concentrations by high performance liquid chromatography and bioactivity by tube dilution bioassay. Following implantation, the highest levels of antibiotics were measured in aliquots of drainage on the first day (vancomycin: 1538.0 +/- 243.6 microg/mL; aztreonam: 1003.5 +/- 323.5 microg/mL), decreasing to 571.9 +/- 169.4 microg/mL for vancomycin and 313.6 +/- 88.3 microg/mL for aztreonam after 7 days. Antibiotic concentrations in serum were very low (vancomycin: 0.58 +/- 0.2 microg/mL, range: 0.1-1.6 microg/mL; aztreonam: 0.46 +/- 0.3 microg/mL, range: 0.1-0.9 microg/mL at 24 h) and there was no systemic adverse effect. At a mean 107 days after the first-stage surgery, the concentrations of antibiotics in joint fluid were well above the minimal inhibitory concentration of most common microorganisms. The released antibiotics were bioactive against the test organisms. Based on the observed results, we confirmed the safety and effectiveness of in vivo drug delivery from antibiotic-impregnated PMMA hip spacers.

Diagnostic value of routine drain tip culture in primary joint arthroplasty

BACKGROUND

Closed suction drainage after joint arthroplasty is common practice in many institutions. The purpose of this study was to determine the correlation between routine drain tip culture and the diagnosis of superficial or deep postoperative wound infection after primary knee and hip replacement.

METHODS

Over a 12-month period, drain tips were retrieved and cultured in all patients who underwent unilateral primary total knee or hip replacement with the use of closed suction drainage. A total of 393 cultures was performed in 387 patients (145 hip replacements, 242 knee replacements). Patients were followed for an average of 8.9 months after surgery to assess for postoperative wound infection.

RESULTS

Three patients had a positive drain tip culture, none of which were diagnosed with superficial or deep infection. Four patients (1%) were diagnosed with deep infection, 16 (4.1%) with superficial infection. No patient with either superficial or deep infection had a positive drain tip culture after their index procedure. The sensitivity of routine drain tip culture for the diagnosis of postoperative infection in primary joint replacement was 0% and specificity was 99.2%.

CONCLUSIONS

These data do not support the practice of routine drain tip culture after primary hip or knee replacement for the diagnosis of postoperative infection.

Suction drain tip culture in orthopaedic surgery: a prospective study of 214 clean operations

We conducted a prospective cohort study in order to determine whether suction drain specimen cultures from orthopaedic surgery predicted an early wound infection. We included 218 consecutive clean orthopaedic operations requiring drains in one unit over a period of 1 year. The suction drain tip, drain fluid and wound discharge specimens were cultured, and the surgical wound was followed up for 3 months. There were six deep and two superficial wound infections. Wound infection was significantly related to positive suction tip culture but not to positive drain fluid culture. Following our methodology for culture, a positive drain tip culture predicts wound infection in 50% and a negative culture virtually excludes the possibility of a deep infection.

The value of suction drainage fluid culture during aseptic and septic orthopedic surgery: a prospective study of 901 patients

There are no guidelines on the value of suction drainage fluid culture (SDC), and it is difficult to determine whether the organisms cultured from suction drainage fluid samples are pathogenic or simply contaminants. We performed 2989 cultures of suction drainage fluid samples obtained, during a 1-year period, from 901 patients who underwent aseptic or septic orthopedic surgery (946 operations). The culture results were analyzed to evaluate their ability to detect postoperative infection after aseptic operations or to detect either a persistent or new episode of sepsis in patients known to have infection. For aseptic operations, the sensitivity of SDC was 25%, the specificity was 99%, the positive predictive value was 25%, and the negative predictive value was 99%. For septic operations, the sensitivity of SDC was 81%, the specificity was 96%, the positive predictive value was 87%, and the negative predictive value was 94%. We conclude that, for aseptic orthopedic surgery, SDC is not useful in detecting postoperative infection. However, for septic orthopedic surgery, it is of clinical importance.

Validity of cultures of fluid collected through drainage catheters versus those obtained by direct aspiration

To examine the validity of cultures of fluid collected through drainage catheters, we reviewed retrospectively fluid specimens that had been collected through catheters in place for at least 2 days. These specimens were taken from patients at a large tertiary-care hospital. A total of 974 specimens representing 620 patient episodes were received. For 554 (89%) episodes there was no reliable imaging evidence for localized infection, rendering the results uninterpretable. The remaining 66 (11%) episodes were followed within 2 days by radiologically guided or open aspiration of one or more fluid collections (predominantly in the abdomen or pelvis) near the drainage catheter, allowing comparison of culture results of 59 direct aspirates with those of prior catheter drainage. In 33 (56%) of these 59 cases, matched culture results were equivalent for therapeutic decision making. However, relying on results of catheter drainage cultures would have led to inadequate antimicrobial therapy in 13 (22%) cases, to excessive therapy in 11 (19%) cases, and to both in 2 cases (3%). We conclude that radiological imaging should be standard practice in the assessment of deep-tissue infections in patients with drainage catheters, and that direct aspiration of potentially infected fluid collections is the most reliable method of obtaining specimens for culture that should be used to guide therapy.

Autotransfusion--bacterial contamination during hip arthroplasty and efficacy of cefuroxime prophylaxis. A randomized controlled study of 40 patients

40 patients undergoing primary hip arthroplasty, given autologous processed blood transfusion, were randomized a receive no antibiotic prophylaxis (group A, n 20) or cefuroxime (1.5 g single injection; group B, n 20). Bacterial contamination at various steps in the autotransfusion procedure was assessed in liquid and solid culture media. The operation field and the wound drainage blood were never contaminated either of the groups but some of the suction tips were. Parts of the Vacufix blood collection bags of group A contained bacteria, but none in group B. Processed red blood cell concentrates in both groups showed bacterial growth. Greater blood loss did not increase the contamination rate in general. Isolated bacteria included the species Staphylococcus epidermidis, coagulase-negative staphylococci and Propionibacteria in both groups, but with different cell counts. In addition, Corynebacterium bovis et minutissimum and Moraxelle were identified in group A. In conclusion, autologous blood transfusion was a safe procedure. If contamination occurred, the bacterial count was low, and the bacteria of low pathogenicity. Antibiotic prophylaxis with cefuroxime reduced this contamination of suction tips and collection bags and limited the transfer of autologous blood products.

Efficacy of closed wound drainage after total joint arthroplasty. A prospective randomized study

The efficacy of closed suction drains following joint arthroplasty operations was prospectively evaluated in a randomized manner. All 88 patients allotted to primary knee or hip arthroplasty operations during a 6-month period were included in the study. Drains were used in 32 of 58 patients following total knee arthroplasty and in 18 of 30 total hip arthroplasties. No statistical difference was found in the hemoglobin levels measured following surgery and in the number of patients requiring blood transfusions between the two groups after total hip arthroplasty (P = .06). The power of the test to detect a difference of 2 g% in hemoglobin levels is 94%. Two patients from each group had a transient serous discharge for 3 to 4 days following surgery and none had wound infections. Significantly more blood transfusions were needed in patients with drains following total knee arthroplasty compared with patients without drains (0.7 unit per patient versus 0.2 unit per patient, P = .005) to maintain the same hemoglobin blood levels. Patients with no drains had significantly more transient sterile serous wound discharge than patients with drains (38.4% vs 12.5%, P = .02). Superficial wound infection necessitating antimicrobial medication developed in one patient with drains and in no patients in the other group. These results suggest that drains may not be needed following total hip arthroplasty. The more common serous wound discharge may be of some concern when drains are not used following total knee arthroplasty.

Preoperative bacterial colonization and its influence on postoperative wound infections in plastic surgery

During two separate periods a total of 654 patients were included in a clinical study relating preoperative bacterial colonization to occurrence of postoperative wound infection in plastic surgery. During the second period one half of the patients were randomized to receive prophylactic azithromycin. Bacteriological samples were collected from the nasal vestibulum during both periods, and additionally from the surgical field during the second period. All patients had preoperative chlorhexidine bathing. The bacteriological findings were categorized as either normal flora or potentially pathogenic bacteria, and as either having no growth. Surgical wounds were divided into four contamination classes. Postoperative follow-up was 30 days, and assessment of wound infection was based on a graded scale. We did not find any statistically significant relation between preoperative bacterial colonization and postoperative wound infection, regardless of place of sample collection, method of bacterial classification, class of contamination or use of prophylactic azithromycin.

Closed suction drainage after hip arthroplasty. Prospective study of bacterial contamination in 81 cases

In a prospective study we analyzed the volume of drainage, the contamination of the drain track, and drain tip in 81 primary total hip arthroplasties in 78 patients. The drain was removed when the drainage from midnight to the following morning was 20 mL or less. The drainage in the first 12 h and in total was reduced in cases with a drain period of 24 h, compared to cases with a drain period of 48 and 72 h. 4 cases had a positive culture from the wound before closure. 5 cases had a positive culture from the tip of the drain, and 6 from the drain track. The most frequently isolated microorganism was coagulase-negative Staphylococcus. The positive cultures from the drain track and tip were not correlated to the duration of drainage. 68 drains were removed within 48 h with no risk of developing wound complications.