Biomedical subjects

Morley A Herbert

Publications and source records attributed to Morley A Herbert.

At least 19 recordsLinked to original sources

PubMed2006

Trinion meniscal screw.

All-inside meniscal repair devices require no accessory incisions, allow faster repairs, and are widely used. The purpose of this study was to determine the in vitro load to failure strength of one new recently released meniscal repair device. Using an established protocol, a vertical longitudinal tear 3 mm from the meniscus periphery was created in 15 porcine menisci and each tear repaired by a single 10-mm Trinion meniscal screw. This repair was pulled apart with loads parallel to the repair axis. Loads to failure and modes of failure were evaluated. The mean load to failure was 38.9 N (SD +/- 9.04) (range, 23.1 to 55.2 N). Two modes of failure were observed: puling out of the inner piece (6 of 15) and of the outer (peripheral) rim (9 of 15). No devices broke. The Trinion meniscal screw is a dual-head design made of trimethylene carbonate, poly L-lactic acid, and poly D, L lactic acid. Its load to failure is similar to other tested devices. The mechanisms of failure were consistent with other all-inside meniscal repair devices. The material properties of a repair device are only one indication of device performance and may not correlate with clinical results.

Animals↗

PubMed2006

Tendon augmentation grafts: biomechanical failure loads and failure patterns.

PURPOSE: The purpose of this study was to determine the load to failure strengths and modes of failure of various commercially available tendon augmentation xenografts and allografts. TYPE OF STUDY: Experimental laboratory study. METHODS: GraftJacket (Wright Medical Technology, Arlington, TN), CuffPatch (Arthrotek, Warsaw, IN), Restore (Depuy, Warsaw, IN), Permacol (Tissue Science Laboratories, Covington, GA; licensed to Zimmer, Warsaw, IN), and TissueMend (TEI Biosciences, Boston, MA; licensed to Stryker Howmedica Osteonics, Kalamazoo, MI) measuring 2 x 5 cm were hydrated according to manufacturers guidelines, a horizontal mattress stitch 5-mm wide was placed 5 mm from the narrow edge of the graft. Tensile loads to failure were applied on the suture while an Instron machine held the graft material and mean loads to failure of the suture graft construct were obtained and modes of graft failure noted. RESULTS: The mean loads to failure were obtained: GraftJacket thin (157 N), GraftJacket MaxForce (182 N), GraftJacket Extreme (229 N), CuffPatch (32 N), Restore (38 N), Permacol (128 N), and TissueMend (70 to 76 N). Failure occurred principally by suture pull-through in all specimens and patterns tended to vary by implant type. CuffPatch and TissueMend tended to fail by isthmus pullout, whereas Restore and Graft jacket failed by end pullout. The tissues were statistically stratified into four groups depending on the material. Human skin (GraftJacket) was the strongest followed by porcine skin (Permacol) and bovine skin (TissueMend). Both in turn were stronger than the porcine small intestine submucosa (Restore and CuffPatch) (P < 0.001). CONCLUSIONS: Suture retention can be reliably tested with a narrow range of standard error utilizing this testing methodology. Skin has higher loads to failure than intestine submucosa. Failure modes differed significantly among the implant types, suggesting that suturing methods for each implant should be considered independently before use. These data cannot be interpreted to suggest that one graft material is clinically superior to another. Rather, each has different properties that the surgeon should recognize when considering their use. CLINICAL RELEVANCE: These grafts have been used as augmentations and substitutions in tendon repairs and as a material for interpositional arthroplasty. These data show that the successful use of these materials requires adequate separation of the fixation sutures and provides an understanding of how each material will fail if subjected to excessive loading during the rehabilitation period.

Bioprosthesis↗

PubMed2006

Sutures and suture anchors--update 2006.

PURPOSE: To evaluate recently introduced sutures and suture anchors for single pull load to failure strength and failure mode. METHODS: Suture anchors were tested in fresh porcine metaphyseal cortex and cancellous troughs with the use of an established protocol. An Instron machine applied tensile loads parallel to the axis of insertion at a rate of 12.5 mm/sec until failure, and mean anchor failure strengths were calculated. The mode of failure (anchor pull-out, suture eyelet cut-out, or suture failure) was recorded. Anchors tested included the BioRaptor 2.9, BioZip, Super Revo, Impact, Allograft cortical anchor, SpiraLok, Herculon, AxyaLoop titanium anchors 3, 5, and 6.5 mm, AxyaLoop bioabsorbable anchors 3, 5, and 6.5, ParaFix titanium anchors 3, 5, and 6.5, ParaSorb BioAnchors 3, 5.5, and 6.5, and Bio-Corkscrew FT. Sutures were also tested through an established protocol for load to failure. Sutures tested consisted of Orthocord, Ultrabraid (White and CoBraid), ForceFiber, Hi-Fi, MagnumWire, and Maxbraid Polyethylene Plus. RESULTS: Mean failure loads were as follows: BioRaptor 238 N, BioZip 366 N, double-loaded Super Revo 486 N, triple-loaded Super Revo 362 N, Impact 202 N, Allograft cortical anchor 240 N, SpiraLok 289 N, Herculon 819 N, AxyaLoop titanium anchors 3.0 (335 N), 5.0 (485 N), and 6.5 mm (465 N), AxyaLoop bioabsorbable anchors 3 (143 N), 5 (395 N), and 6.5 (369 N), ParaFix titanium anchors 3 (335 N), 5 (485 N), and 6.5 (465 N), ParaSorb BioAnchors 3 (143 N), 5.5 (395 N), and 6.5 (369 N), and Bio-Corkscrew FT (260 N). The sutures all broke at the mid point of their tested strands away from the grips. Mean suture strength for No. 2 Orthocord was 92 N; for No. 2 Ultrabraid CoBraid and White, strengths were 265 N and 280 N, respectively; strength for No. 2 Force Fiber was 289 N, for No. 2 Hi-Fi 250 N, for No. 2 MagnumWire 303 N, and for No. 2 Maxbraid Polyethylene Plus 256 N. CONCLUSIONS: Newer suture products showed significant improvements in load to failure values when compared with braided polyester sutures. Higher load to failure values continue to be seen in metal versus biodegradable anchors and in screw-type versus nonscrew designs. CLINICAL RELEVANCE: Surgeons who prefer stronger sutures now have several high-strength suture options from which to choose. Most of the new anchors tested performed very well.

Animals↗

PubMed2006

Does coronary artery bypass graft surgery improve survival among patients with end-stage renal disease?

BACKGROUND: Cardiovascular disease remains the most frequent cause of death for patients with end-stage renal disease. To determine the long-term benefit of surgical revascularization in this high-risk population, we studied our patients with ESRD having coronary artery bypass graft surgery (CABG), comparing the results of off-pump to on-pump revascularization. As a baseline reference group, we used dialysis patients with a diagnosis of coronary artery disease who did not have surgical revascularization or percutaneous coronary interventions. The control group data set was obtained from the United States Renal Data System. METHODS: From January 1995 through July 2003, 158 patients with end-stage renal disease who were on hemodialysis (excluding those in cardiogenic shock, needing resuscitation, and with emergent or salvage status) underwent CABG. Fifty-nine patients (37.3%) had off-pump revascularization, and 99 patients (62.7%) had bypass grafting utilizing extracorporeal circulation. Preoperative risk factors and operative results were analyzed, and longitudinal survival data obtained. RESULTS: The mean follow-up time was 39.1 months (median, 33.1) for the on-pump patients and 18.3 months (median, 14.7) for off-pump. The total number of anastomoses per off-pump patient was 2.4 +/- 1.0, and with cardiopulmonary bypass (CPB), it was 3.3 +/- 0.9 (p < 0.001). Patients revascularized off-pump had an operative mortality rate of 1.7%, whereas patients grafted using CPB had an operative mortality of 17.2% (p = 0.003). The predicted risk of mortality for the off-pump group (9.3% +/- 7.4%) was not statistically different from the on-pump cohort (9.1% +/- 7.7%, p = not significant). Logistic regression analysis indicates that CPB use was an independent risk factor for early death (p = 0.01, odds ratio = 13.6, 95% confidence interval: 1.7 to 110). Long-term follow-up demonstrated that the patients revascularized using CPB had improved survival compared with the off-pump patients and the control population. CONCLUSIONS: Off-pump CABG improves early mortality rate when compared with conventional revascularization. Despite a greater operative mortality, however, long-term survival is improved in the patients revascularized with CPB as compared with the off-pump cohort, suggesting possible advantages from a more complete revascularization in this population.

Aged↗

PubMed2006

One-year follow-up after thoracoscopic sympathectomy for hyperhidrosis: outcomes and consequences.

BACKGROUND: Thoracic sympathectomy is recognized as an effective treatment for patients with severe hyperhidrosis. While good early results have been documented, continuing efficacy and patient satisfaction has not been well-defined. We reviewed our results in patients who were at least one year out from surgery. METHODS: All procedures were performed thoracoscopically using bilateral 3 mm ports and excision of a segment of the sympathetic chain by electrocautery. The level of sympathectomy depended upon clinical symptoms: T2 for face/scalp, T3 for palmar hyperhidrosis, and T4 for axillary hyperhidrosis, or a combination of levels for multiarea sweating. All patients were followed-up at least 1 year postprocedure by mail questionnaire and/or telephone. RESULTS: Two hundred twenty-two patients had undergone thoracoscopic sympathectomy for essential hyperhidrosis between Jan 1, 2002 and Nov 30, 2003, with 170 patients having at least one-year follow-up. The patients' preoperative assessment of the severity of sweating in the affected areas was compared with their one-year evaluation in order to determine the durability of the procedure. All affected areas continued to show significant improvement in sweating as compared with preoperative symptoms. Compensatory sweating was reported in 85% of our patients at one-year follow-up. Patients with a T2 lesion were significantly more likely to have severe compensatory sweating than those with other levels; 48.8% vs 16.1% (p < 0.001). Patients with levels other than T2 reported high degrees of satisfaction unrelated to their postoperative compensatory symptoms. CONCLUSIONS: Patient satisfaction and perceived effectiveness with sympathectomy for palmar or axillary hyperhidrosis remain high even one year after the procedure. Inclusion of the T2 lesion results in significantly more severe compensatory sweating and reduced satisfaction than other levels.

Adolescent↗

PubMed2006

Reduced atrial fibrillation in patients immediately extubated after off-pump coronary artery bypass grafting.

BACKGROUND: We analyzed data from patients undergoing off-pump isolated coronary artery bypass grafting surgery (OPCABG) to determine if immediate extubation in the operating room affected the incidence of postoperative atrial fibrillation. METHODS: The study group comprised 2,376 consecutive OPCABG patients operated on between January 1, 2000, and December 31, 2004, by 22 surgeons at 18 hospitals. The data were subjected to univariate, multivariate analysis of variance, and logistic analysis. Logistic regression of matched groups was used to eliminate the effect of some confounding variables. RESULTS: Patients immediately extubated after surgery had a reduced incidence of atrial fibrillation (10.6% versus 18.5%; p < 0.001), shorter length of stay (4.8 +/- 3.5 versus 6.3 +/- 5.2 days; p < 0.001), and also reduced mortality (1.1% versus 2.4%; p = 0.04). Logistic analysis identified as significant factors for postoperative atrial fibrillation, postoperative ventilator usage (p < 0.001; odds ratio [OR] = 1.63; 95% confidence interval [CI]: 1.24 to 2.14), male sex (p = 0.002; OR = 1.51; 95% CI: 1.17 to 1.96), previous CABG (p = 0.005; OR = 0.43; 95% CI: 0.24 to 0.78). Congestive heart failure may also be a contributing factor. In patient groups matched for their risk of mortality, postoperative ventilator use (p < 0.001; OR = 1.80; 95% CI: 1.31 to 2.47), increasing age, and male sex were all statistically significant risk factors. When patient groups were matched on a combination of factors including preoperative beta-blocker usage, pulmonary disease, and smoking, postoperative ventilator use (p = 0.005; OR = 1.66; 95% CI: 1.16 to 2.38), along with increasing age, male sex, and previous CABG (reduced odds of atrial fibrillation developing) were statistically significant. CONCLUSIONS: Immediate extubation after OPCABG appears to reduce the incidence of postoperative atrial fibrillation independent of comorbidities.

Adrenergic beta-Antagonists↗

PubMed2006

The occurrence of postoperative pulmonary homograft stenosis in adult patients undergoing the Ross procedure.

BACKGROUND AND AIM OF THE STUDY: The Ross procedure employs an autologous pulmonary valve to replace the aortic valve, but requires pulmonary homograft replacement. Concerns regarding long-term homograft function may limit the adoption of this technique. Herein, the incidence of, and factors leading to, stenosis of the homograft were examined. METHODS: Data were collected from 131 patients (32 females, 99 males) who underwent a Ross procedure between July 1994 and December 2003. Complete follow up data were collected from 113 of 125 (90.4%) living patients. Donor valve information, including storage time, was supplied by the graft manufacturers. Data were analyzed using chi-square tests, t-test and logistic regression. RESULTS: The mean patient follow up was 703 +/- 574 days (median 599 days; range: 2 to 2,408 days). Echocardiographic stenosis had occurred in 14 patients (12.4%). Four patients (3.2%) required homograft replacement, and two required balloon valvuloplasty. There was no significant difference in graft vendor, recipient, donor age or blood type match between stenotic and non-stenotic recipients. Donor valve size was appropriate for the recipients, and greater than predicted by recipient body surface area (BSA). Donor valves that developed stenosis had a shorter storage time after processing (160 +/- 100 versus 249 +/- 223 days; p = 0.03). Male donor valves became stenotic in 9.9% (7/71) of male recipients, but in none of 20 females. Female donor valves became stenotic in 27.3% (3/11) of male recipients, and in 28.6% (2/7) females. Logistic regression showed donor gender to be a significant predictor for stenosis (p = 0.007; odds ratio 14.1 for female/male donors; 95% CI 2.1-96.4). CONCLUSION: Donor valves which developed stenosis had a shorter mean cryopreservation time than those that did not develop stenosis. In addition, female donor homografts appeared to develop stenosis at a greater rate, independent of patient age, graft size to BSA match, and blood type.

Adolescent↗

PubMed2005

Compressive loads in longitudinal lateral meniscus tears: a biomechanical study in porcine knees.

PURPOSE: To determine the displacement forces across a lateral meniscal tear during motion. TYPE OF STUDY: Experimental laboratory biomechanical study. METHODS: A middle third longitudinal lateral meniscal cut was created arthroscopically at the "red-white" junction in 5 intact porcine knees. With a pressure transducer in the tear, the knees were repeatedly cycled through a full range of motion. Pressure data were gathered with the knees held at neutral, internal rotation (IRot), and external rotation (ERot) and matched to the specific flexion angle measured by electronic goniometer. Averaged pressure measurements were calculated at each 5 degrees interval. RESULTS: The highest pressures were seen at full extension (neutral, 589 mm Hg; IRot, 1,110 mm Hg; ERot, 337 mm Hg) and declined to a low at 90 degrees of flexion (neutral, 133 mm Hg; IRot, 314 mm Hg; ERot, 187 mm Hg). Then the pressures increased steadily after 100 degrees as the knees were further flexed. The highest pressure was always seen with IRot. IRot during flexion resulted in higher lateral meniscus compressive loads than ERot. CONCLUSIONS: This model demonstrated that a middle third longitudinal lateral meniscal cut is compressed throughout the full range of knee motion. At no time were negative intrameniscal tear pressures registered that would suggest meniscal cut separation. CLINICAL RELEVANCE: These data suggest that meniscal compressive loads, not distractive loads, occur throughout knee flexion and extension. The absence of distractive loads across a meniscal cut suggests that the ability of a repair to align the meniscal fragment may be more important than a high load to failure strength.

Animals↗

PubMed2005

Invited commentary.

Explore the source record for details and available documents.

Coronary Artery Bypass↗

PubMed2005

Routine immediate extubation after off-pump coronary artery bypass surgery: 514 consecutive patients.

OBJECTIVE: The purpose of this study was to evaluate the feasibility of routine immediate extubation in patients undergoing off-pump coronary artery bypass surgery. DESIGN: Case series. SETTING: Private hospital. PARTICIPANTS: Five hundred forty-eight consecutive patients undergoing off-pump coronary bypass surgery, representing 5 years of a single anesthesiologist's practice, were evaluated for routine immediate extubation. Thirty-four patients were excluded because they were already intubated, in preoperative cardiogenic shock, or converted to on-pump during the procedure. INTERVENTION: Patients received general anesthesia or general anesthesia plus thoracic epidural analgesia (25%) and underwent off-pump coronary bypass surgery. MEASUREMENTS AND MAIN RESULTS: All 514 patients who were intended to be immediately extubated were expeditiously extubated in the operating room. The numbers of reintubations, morbidity, and mortality were low. CONCLUSIONS: Routine immediate extubation of most off-pump coronary artery bypass patients appears feasible and most probably safe.

Aged↗

PubMed2005

Mitral valve surgery using the classical 'heartport' technique.

BACKGROUND AND AIM OF THE STUDY: Mitral surgery in selected patients using femoral cannulation, percutaneous retrograde cardioplegia and endoballoon aortic occlusion with a 4-5 cm thoracotomy is felt to carry a higher operative risk than sternotomy with conventional cannulation. Herein, the authors compared their experience of the first 117 'Heartport' (HP) patients with a computer-matched group of sternotomy approach surgical patients (SP) to assess operative risk and 30-day outcome. METHODS: Data were extracted from the authors' STS certified, audited database on 117 patients based on an intention to treat. Between December 1997 and December 2004, a total of 92 isolated mitral valve (MV) repair (HP-MVRpr) and 25 isolated MV replacement (HP-MVR) procedures was conducted using Heartport. The patients were matched 1:1 (by age +/-7 years, cerebrovascular disease, inotrope use, and ejection fraction +/- 5%) to a control SP group. Operative and 30-day outcomes were measured. RESULTS: No parameter showed any significant difference in 30-day outcome between the HP and SP groups, except for an increase in cross-clamp and perfusion times. Two patients in the HP-MVRpr group required conversion to sternotomy for repair of coronary sinus perforation, and one patient was repaired without conversion. Surgery in one HP-MVRpr patient was aborted due to limited aortic dissection, but successful repair was carried out later with a conventional approach. No patient required conversion to sternotomy for improved exposure of the operative site. CONCLUSION: Despite a longer cross-clamp time, 'classical' HP MV surgery can be performed with no increased risk compared to conventional MV surgery. Catheter and endoballoon complications were rare even in the early experience, and conversion to sternotomy was unusual and safely performed with this approach.

Adult↗

PubMed2004

Experience with various surgical options for the treatment of atrial fibrillation.

BACKGROUND: New alternatives exist using various energy sources and lesion lines for the surgical treatment of atrial fibrillation (AF). The efficacy of these options compared to the cut-and-sew maze III procedure is unknown. METHODS: From August 1996 to August 2003, 79 patients have undergone a procedure for AF, with 70 patients currently more than 3 months postsurgery. The patients (58 continuous, 12 paroxysmal) underwent a surgical procedure for AF, lone AF (12) and with concomitant procedures (58). Techniques included cut and sew (23), bipolar radiofrequency (RF) (28) and unipolar-RF (10), and cryothermy (9). Lesions included maze III (46), pulmonary vein isolation (16), and pulmonary vein isolation plus mitral annular connecting line only (8). RESULTS: Follow-up was complete in 58 (83%) of 70 patients at a mean time of 595 +/- 750 days (range, 24-2530 days). The operative mortality was 0% in lone AF patients and 7.1% (5/70) in patients undergoing concomitant procedures. Need for perioperative pacemaker was 22.9%. Overall, normal sinus rhythm (NSR) was restored in 82.7% of patients, with success in 83.3% (10/12) lone procedures and 82.6% (38/46) concomitant procedures ( P = NS); the rate of continuous AF was 85.1% (40/47) and SR with paroxysmal fibrillation was 72.7% (8/11) ( P = NS). Traditional maze was successful in 80.6% (29/36) patients, pulmonary vein isolation was successful 93.3% (14/15), and left-sided maze in 71.4% (5/7) ( P = NS). Cut and sew procedures were successful in 88.2% (15/17), RF-bipolar in 84.0% (21/25), RFunipolar in 77.8% (7/9), and cryothermy in 71.4% (5/7) ( P = NS). Energy source, lesion set, AF duration, and lone/concomitant procedure were the factors subjected to logistic regression analysis. No factors were predictive of achieving postoperative NSR. CONCLUSIONS: Our early experience with newer surgical techniques employing different energy sources and fewer incision lines suggests that the success rate may approach the results obtained with traditional cut-and-sew Cox-maze III procedures.

Atrial Fibrillation↗

PubMed2004

Load to failure testing of new meniscal repair devices.

PURPOSE: New all-inside meniscal repair devices include those combining sutures with anchors and that allow for an "adjustable" repair. This study's purpose was to compare the failure strength of new meniscal repair devices with suture repairs. TYPE OF STUDY: Experimental laboratory biomechanical study. METHODS: A single repair was placed in a vertical longitudinal peripheral tear made in fresh adult porcine menisci. Group 1 had a vertically oriented suture using the FasT-Fix (Smith & Nephew Endoscopy, Andover, MA) device. Group 2 had a horizontally oriented mattress suture using the FasT-Fix device. Group 3 had a repair using 2 Arthrex (Naples, FL) meniscal darts. The Group 4 repair used a RapidLoc (Mitek Surgical Products, Westwood, MA) device. The Group 5 repair used the Arthrotek meniscal screw (Biomet, Warsaw, IN). Group 6 had a single vertical suture, and group 7 a single horizontal suture, both of 2-0 Mersilene (Ethicon, Somerville, NJ). Load to failure testing was performed. RESULTS: The vertical FasT-Fix suture had a mean load to failure of 70.9 N (1 SD +/- 33). The horizontal FasT-Fix suture had a mean load to failure of 72.1 N (+/- 23.5). The double Dart repair had a mean load to failure of 61.7 N (+/- 19). The RapidLoc repair had a mean load to failure of 43.28 N (+/- 3.98). The Arthrotek meniscal screw repair had a mean load to failure of 28.09 N (+/- 7.93). Failure occurred with device pullout of the inner rim (9 of 10) for the Darts, device pullout of the inner rim (6 of 10) and pullout of the outer rim (4 of 10) for the Arthrotek screw, and suture breakage for the FasT-Fix and the RapidLoc devices. The vertical sutures' mean load to failure was 80.43 N (+/- 8.5), and all 13 failed by suture breaking. The horizontal sutures' mean failure load was 55.9 N (+/- 18.8), and failure was by both suture breaking (6 of 10) and pulling through the meniscal tissue (4 of 10). CONCLUSIONS: Some of the newer meniscal repair devices show improved loads to failure over earlier generations.

Animals↗

PubMed2004

First-year outcomes of beating heart coronary artery bypass grafting using proximal mechanical connectors.

BACKGROUND: To determine the extended results of mechanical connectors we compared the 1-year outcomes of patients having beating heart coronary artery bypass surgery with at least one sutured or mechanically connected proximal vein graft anastomosis. METHODS: From May 2001 to December 2001, 166 patients were identified as having undergone off-pump bypass grafting utilizing at least one St. Jude symmetry aortic connector (St Jude Medical Anastomotic Technology Group, St. Paul, MN). Follow-up for major adverse cardiac events (MACEs), which is defined as cardiac mortality, myocardial infarction, or revascularization of a previous target vessel, was obtained on 162 patients (97.6%). A control group of 159 patients was identified from a cohort of patients having beating heart surgery with one or more sutured proximal vein graft anastomosis in the preceding year. The MACE follow-ups were obtained in 136 patients (85.6%) by direct telephone contact. RESULTS: Patients with connectors showed an accelerated number of MACEs beginning approximately 180 days from the time of surgery and stabilizing at approximately 300 days. Logistic regression analysis identified the presence of diabetes as a significant preoperative risk factor predisposing patients to earlier onset of MACEs (p = 0.03) with an odds ratio of 2.9 (95% confidence interval, 1.1 to 7.6). Insulin dependent diabetics showed no differences between connector and control patients in the frequency or timing of MACEs. Connector patients using oral hypoglycemic agents demonstrated a significant deviation (p = 0.01) from a similar control population in the prevalence and timing of MACEs. CONCLUSIONS: Connector patients showed an increased incidence of early MACEs. These events were characterized by an increased requirement for early target vessel revascularization and were predominantly in noninsulin-dependent diabetics.

Aged↗

PubMed2004

Are unaudited records from an outcomes registry database accurate?

BACKGROUND: Data from outcomes registry databases are being increasingly used for peer review and public reporting. However, administrative and clinical databases are mostly unaudited; thus, their accuracy has not been verified. METHODS: Outcomes data from all coronary artery bypass operations from a single cardiac surgery practice were entered into The Society of Thoracic Surgeons (STS) National Cardiac Database. From our practice of 18 surgeons, we audited 247 (10%) of the clinical records of patients undergoing surgery in 2001 and correlated them with all 315 elements of the STS National Cardiac Database for verification of accuracy. Inaccuracies were defined as a disagreement with a nominal or categorical variable or, for continuous variables, as the value not being within a predetermined window. When discrepancies existed, the hospital clinical record was assumed to be accurate. Outcomes discrepancies were then analyzed by four major categories: components of the preoperative risk algorithm, operative mortality, major complications, and other outcomes. RESULTS: Discrepancies were noted in 5% (16) or fewer of the audited fields for 98.8% of the records. Of the 32 variables in the mortality risk algorithms, discrepancies were present in fewer than 10% of the audits on 30 of the 32 variables. More than 95% of the audited charts had zero or one discrepancy in the seven most important variables in the mortality risk models. Operative mortality was determined to be completely accurate with no discrepancies between the database and the audited clinical record. Among major complications, the error rate was less than 1% for all complications except prolonged ventilation (4.0%). A higher rate of discrepancies did exist in some of the other variables, including discharge medications (14.1%) and ventilator time (36.4%). CONCLUSIONS: A detailed audit of a clinical outcomes registry database demonstrated that the major fields within this specific database including operative mortality, major complications, and the significant factors in the risk algorithm were highly accurate. Process improvement factors were identified to further increase the accuracy of data collection.

Cardiac Surgical Procedures↗

PubMed2004

Port-access aortic valve surgery: a technique in evolution.

BACKGROUND: Innovative minimally invasive surgical techniques have been developed for treating many cardiac diseases. We reviewed our experience with port-access aortic valve replacement (PAVR) surgery. METHODS: We retrospectively reviewed the charts of patients with aortic valve disease who underwent surgical correction using the Heartport System and minithoracotomy (PAVR) from January 1998 to December 2002 (n = 58) and matched them 1:1 with a cohort of patients who underwent AVR with conventional sternotomy. RESULTS: No preoperative statistical differences existed between the groups, including age, sex, New York Heart Association class, and ejection fraction. Perioperatively, there was a statistically significant difference between the AVR and PAVR groups with regard to aortic cross-clamp time (74.0 +/- 22.9 minutes versus 92.7 +/- 20.4 minutes, P < .01). Average operative times improved in the PAVR group by almost 83 minutes from the first 10 patients to patients 21 to 31 (P = .05). PAVR patients also averaged shorter stays in the intensive care unit (ICU) (1.5 days less) and hospital (1.8 days less) and were extubated sooner (4.9 hours). Mortality (1/58, 1.7%) and morbidity (reoperation for bleeding, infection, and stroke) were similar for both groups. CONCLUSIONS: This minimally invasive approach to aortic valve surgery allows patients to be extubated earlier and promotes shorter stays in the ICU and hospital. These data suggest that the PA approach is an attractive alternative for patients requiring aortic valve surgery. There also appears to be a rapid surgeon learning curve.

Aged↗

PubMed2003

Sutures and suture anchors: update 2003.

PURPOSE: The purpose of this study was to evaluate recently introduced sutures and suture anchors for single-pull load-to-failure strength and failure mode. TYPE OF STUDY: Experimental laboratory biomechanical study. METHODS: Using an established protocol in fresh porcine femurs, anchors were tested in diaphyseal cortex, metaphyseal cortex, and cancellous troughs after threading them with either steel sutures or strong synthetic material to reduce the likelihood of suture breakage as a mode of failure. An Instron machine (Instron, Canton, MA) applied tensile loads parallel to the axis of insertion at a rate of 12.5 mm/second until failure, and mean anchor failure strengths were calculated. Mode of failure was recorded (anchor pullout, suture eyelet cutout, or wire breakage). Anchors tested included the RotorloC (Smith & Nephew Endoscopy, Andover, MA), TwinFix Ti 3.5, TwinFix Ti 5.0, and TwinFix AB (Smith & Nephew Endoscopy), Super Revo and UltraSorb (Linvatec, Largo, FL), Duet (Bionx Implants, Blue Bell, PA), AlloAnchor RC (Regeneration Technologies, Alachua, FL), Opus Magnum anchor (Opus Medical, San Juan Capistrano, CA), and the BioCorkscrew 5.0 and BioCorkscrew 6.5 (Arthrex, Naples, FL). Sutures tested were No.2 and No. 5 Ethibond (Ethicon, Somerville, NJ), No. 2 Panacryl (Mitek, a division of Ethicon, Somerville, NJ), and Nos. 2, 5, and 2-0 Fiberwire (Arthrex, Naples, FL). RESULTS: The sutures all broke in the midpoint of their tested strand away from the grips. The No. 2 Ethibond failed at a mean of 21 lb (92 N); No. 5 Ethibond failed at a mean of 44 lb (193 N); No. 2, No. 5, and No. 2-0 Fiberwire at means of 44 lb (188 N), 112 lb (483N), and 19 lb (82 N), respectively; and No. 2 Panacryl at a mean of 22 lb (99 N). The suture anchors all failed at levels higher than the associated sutures. CONCLUSIONS: Screw anchors showed higher load to failure values than nonscrew designs, and the new biodegradable anchors showed failure loads lower than the anchors. All anchors were stronger than the suture for which they are designed.

Animals↗

PubMed2003

Conversion in off-pump coronary artery bypass grafting: an analysis of predictors and outcomes.

BACKGROUND: The incidence, predictive factors, and outcomes related to conversion from off-pump coronary artery bypass (OPCAB) to on-pump coronary artery bypass grafting (ONCAB) have not been well defined. We sought to determine the incidence of conversion, predictive factors, and any associated adverse consequences. METHODS: From January 2000 through June 2002, 1,644 patients underwent nonemergent OPCAB with 61 patients requiring conversion from OPCAB to ONCAB. These groups were retrospectively compared by univariate and multivariate regression analysis. The converted group was then computer matched 1:3, to a cohort of ONCAB patients to determine differences in outcomes. RESULTS: The overall conversion rate was 3.71%. Converted patients compared with a computer-matched ONCAB patients had a higher incidence of operative mortality (18.0% versus 2.7%, p < 0.001). Urgently converted patients had a higher incidence of postoperative cardiac arrest (25% versus 1.1%, p < 0.001), multisystem organ failure (10.7% versus 0.6%, p < 0.001), vascular complications (7.1% versus 1.1%, p = 0.03), and perioperative myocardial infarction (10.7% versus 1.1%, p = 0.02). Predictive factors for conversion were surgeon early in OPCAB experience (odds ratio [OR] 4.4), previous CABG (OR 2.8), and congestive heart failure (OR 2.0). The need for urgent-emergent conversion was highly predictive for operative mortality (OR 7.3) compared with elective conversion. CONCLUSIONS: Patients undergoing urgent-emergent but not elective conversion from OPCAB to ONCAB had a significantly higher risk of mortality and morbidity compared with patients whose procedure was initially ONCAB. Variables predictive of conversion included previous CABG, congestive heart failure, and surgeons early in OPCAB experience.

Cardiopulmonary Bypass↗