Operational aspects of bednet impregnation for community-based malaria control in Nicaragua, Ecuador, Peru and Colombia

OBJECTIVES: The authors tested the ability of International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes in discharge abstracts to identify medical inpatients who experienced an in-hospital complication, using complications identified through chart review as the gold standard. METHODS: Two sets of ICD-9-CM codes were used: an inclusive set including many medical diagnoses that may also be coexistent complicating conditions on admission rather than complications and an exclusive set consisting primarily of ICD-9-CM-specified complication and adverse drug event codes. RESULTS: Neither set performed well as a diagnostic test for complication occurrence according to receiver operating characteristic analysis (ROC areas were 0.61 for the inclusive set and 0.55 for the exclusive set). Sensitivities of the ICD-9-CM codes for complications were 0.34 for the inclusive set and 0.14 for the exclusive set. Corresponding positive predictive values were 0.32 and 0.37, respectively. Sensitivities of code definitions for individual complications were generally poor, less than 0.5 in most cases. CONCLUSIONS: The authors conclude that ICD-9-CM codes in discharge abstracts are poor measures of complication occurrence.     

Accuracy of ICD-9-CM coding for the identification of patients with acute ischemic stroke: effect of modifier codes

BACKGROUND AND PURPOSE: Discharge ICD-9-CM (International Classification of Diseases, 9th Revision, Clinical Modification) codes have been used to identify patients with acute stroke for epidemiological, quality of care, and cost studies. The aim of this study was to determine if the accuracy of the primary ICD-9-CM codes for ischemic stroke is improved by modifier codes and how specific codes reflect stroke subtype diagnoses. METHODS: Available hospital charts for all patients discharged from a single hospital between May 1995 and June 1997 with ICD-9-CM codes 433 (occlusion and stenosis of precerebral arteries), 434 (occlusion of cerebral arteries), or 436 (acute but ill-defined cerebrovascular disease) listed in the first position were reviewed. The primary discharge diagnosis was verified, and a presumed stroke subtype was assigned on the basis of information provided in the medical record. RESULTS: Charts were available for 175 of the 198 identified patients (88%). Of these, 61% had an acute ischemic stroke (code 433, 4%; 434, 82%; 436, 79%) with the remaining patients having other conditions. Of the 130 patients with a modifier code indicating cerebral infarction, 79% had an acute stroke; of the 45 patients with a modifier code indicating an absence of cerebral infarction, 7% had acute stroke (sensitivity, 0.97; specificity, 0.60). The codes with the highest proportions of ischemic stroke cases were 434.11 (embolic occlusion of cerebral arteries with infarction, 85%), 434.91 (unspecified occlusion of precerebral arteries with infarction, 82%), and 436 (79%), with a combined sensitivity of 0.81 and specificity of 0.90. On review, 73% of patients with code 434.11 had embolic strokes, and 47% of those with code 436 had an identified stroke cause. Of patients with code 434.91, 39% had stroke of uncertain cause, 25% "lacunar," 17% atherothrombosis, and 15% embolism. CONCLUSIONS: Despite the use of modifier codes, 15% to 20% of patients with the indicated primary ICD-9-CM codes have conditions other than acute ischemic stroke. Although the proportion of patients with acute stroke increased from 61% to 79% with the use of modifier codes, the inclusion of modifier codes did not have an appreciable effect on the accuracy of the coding if patients with code 433 are excluded. Assignment of presumed ischemic stroke subtype is particularly inaccurate.     

Accuracy of ICD-9-CM codes in detecting community-acquired pneumococcal pneumonia for incidence and vaccine efficacy studies

Studies have used medical record discharge data as coded by the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) to estimate pneumococcal pneumonia incidence and vaccine efficacy. However, the accuracy of coding data to identify laboratory-confirmed pneumococcal pneumonia is not known. With the use of information collected in Ohio for a community-based pneumonia incidence study, the authors calculated the sensitivities, specificities, positive predictive values (PPV), and negative predictive values (NPV) of specific codes for pneumococcal pneumonia among hospitalized patients with community-acquired pneumonia. Sensitivities of the most common ICD-9-CM codes listed in the first five positions for patients with laboratory-confirmed pneumococcal pneumonia were 58.3% (code 481.0, pneumococcal pneumonia), 20.4% (38.0, streptococcal septicemia), 19.2% (38.2, pneumococcal septicemia), 15.0% (518.81, respiratory failure), 14.2% (486.0, pneumonia, organism unspecified), and 11.3% (482.3, streptococcal pneumonia). Using the first five listed ICD-9-CM codes rather than just the first listed code increased sensitivity without causing substantial change in specificity, PPV, and NPV. Sensitivity, PPV, and NPV of individual and groups of codes varied with different case definitions of pneumococcal pneumonia. Incidence and vaccine efficacy studies with the ability to validate diagnoses by medical chart review can use a combination of many ICD-9-CM codes to maximize sensitivity. However, without the ability to review medical charts, researchers must carefully decide which codes would best suit their studies.     

Validation of relative value scale for congenital heart operations

BACKGROUND: To determine the validity of the newly assigned work relative value unit (RVU) scale for surgical procedures for congenital heart disease, we measured its relationship to length of hospital stay, total hospital charges, and mortality. METHODS: We identified cases by the presence of ICD-9-CM codes in nine statewide, administrative hospital discharge abstract databases for 1992. Computer algorithms were generated to assign RVUs to individual cases. Spearman correlation coefficients between work and practice expense RVUs and median length of hospital stay, total hospital charges, and in-hospital mortality were determined, as well as parameter estimates from linear and logistic regression. RESULTS: Using data from 5,192 cases involving 34 surgical procedures for congenital heart disease, higher work RVUs were associated with longer lengths of hospital stay (rs = 0.72, p < 0.0001), higher total hospital charges (rs = 0.81, p < 0.0001), and higher in-hospital mortality (rs = 0.45, p = 0.01). A 5-point increase in the relative value scale was associated with an increase in the length of stay by a multiplicative factor of 1.3 (p < 0.0001); total hospital charges by 1.5 (p < 0.0001); and the odds of in-hospital death by 1.9 (p < 0.0001). Findings were similar for practice expense RVUs, as work and practice expense RVUs were highly correlated (rs = 0.93, p < 0.0001). CONCLUSIONS: The group of work RVUs for surgical procedures for congenital heart defects are reasonable relative measures, on average, of physician work for these procedures, thus supporting the use of this scale to determine physician reimbursement. Practice expense RVUs may not be an independent measure for these procedures.     

Accuracy of injury coding in Victorian hospital morbidity data

In Victoria injury surveillance data are drawn from hospital morbidity data. The accuracy and reliability of these data are often questioned. We aimed to ascertain the reliability of injury data in the Victorian inpatient minimum database. A random sample of 546 public hospital separations with principal diagnosis ICD-9-CM codes 800-999 was selected from four metropolitan hospitals. Medical records were reviewed, and the hospital coding was compared with the record content. The frequency of error in any coding field was 73 per cent (349/480); of diagnosis error, 61 per cent (292/480); of procedure error, 45 per cent (168/370); of error in the principal diagnosis, 19 per cent (93/480); and of error in external-cause codes (E-codes), 16 per cent (75/480). Ninety-four per cent of errors (87/93) in the principal diagnosis involved recoding within the same group of codes. Only 6 per cent (6/93) were recoded to principal diagnoses other than injury. Sixty-two per cent (181/292) were errors of omission of codes for comorbid conditions. Nearly half the errors in the principal diagnosis were minor, involving the last two digits. E-codes were more complete than diagnosis codes. The best predictors of error in the principal diagnosis were greater length of stay, type of injury code (poisonings and toxic effects were associated with lower error rates) and death as the outcome. While selection of data from secondary diagnosis fields may not provide complete data, the use of the principal-diagnosis code and E-codes for injury surveillance is feasible and reliable. The database is a valuable source of injury surveillance data, bearing in mind the limitations of coded hospital morbidity data.     

The surgical treatment of low back pain

If nonoperative management fails to relieve a clearly identifiable and surgically treatable cause of lumbar pain, then surgery may be beneficial. Certain "red flags" indicate the need for urgent or emergent surgical intervention. Low back pain is associated with several degenerative conditions in the lumbar spine, including degenerative disc disease, spinal stenosis, spondylolisthesis, degenerative scoliosis, facet joint syndrome, and disc herniation.     

Computer-assisted measurement of lumbar spine radiographs

RATIONALE AND OBJECTIVES: The authors evaluated a method for obtaining reproducible, reliable measurements from standard lumbar spine radiographs for determining the degree of spondylolisthesis, vertebral body height, intervertebral disk space height, disk space angle, and degree of vertebral body wedging. MATERIALS AND METHODS: Four to six easily defined points were identified on each vertebral body on anteroposterior and lateral plain radiographs of the lumbosacral spine of patients. From these points, the degree of spondylolisthesis, the vertebral body height, the intervertebral disk space height, the disk space angle, and the degree of vertebral body wedging were easily calculated by using well-known geometric relationships. This method requires the use of a personal computer and a standard spreadsheet program but does not require the use of any other specialized radiographic equipment, computer hardware, or custom software. RESULTS: Calculations of intra- and interobserver variability for the measurement of spondylolisthesis, disk space height, disk space angle, and vertebral body height measurement showed that the technique is extremely reproducible. CONCLUSION: This technique may prove useful in the prospective evaluation of potential candidates for lumbar spinal stenosis surgery.     

Evaluation of specific stabilizing exercise in the treatment of chronic low back pain with radiologic diagnosis of spondylolysis or spondylolisthesis

STUDY DESIGN: A randomized, controlled trial, test--retest design, with a 3-, 6-, and 30-month postal questionnaire follow-up. OBJECTIVE: To determine the efficacy of a specific exercise intervention in the treatment of patients with chronic low back pain and a radiologic diagnosis of spondylolysis or spondylolisthesis. SUMMARY OF BACKGROUND DATA: A recent focus in the physiotherapy management of patients with back pain has been the specific training of muscles surrounding the spine (deep abdominal muscles and lumbar multifidus), considered to provide dynamic stability and fine control to the lumbar spine. In no study have researchers evaluated the efficacy of this intervention in a population with chronic low back pain where the anatomic stability of the spine was compromised. METHODS: Forty-four patients with this condition were assigned randomly to two treatment groups. The first group underwent a 10-week specific exercise treatment program involving the specific training of the deep abdominal muscles, with co-activation of the lumbar multifidus proximal to the pars defects. The activation of these muscles was incorporated into previously aggravating static postures and functional tasks. The control group underwent treatment as directed by their treating practitioner. RESULTS: After intervention, the specific exercise group showed a statistically significant reduction in pain intensity and functional disability levels, which was maintained at a 30-month follow-up. The control group showed no significant change in these parameters after intervention or at follow-up. SUMMARY: A "specific exercise" treatment approach appears more effective than other commonly prescribed conservative treatment programs in patients with chronically symptomatic spondylolysis or spondylolisthesis.     

Transcutaneous or transconjunctival peribulbar anesthesia?

The complications of 648 consecutively inserted Universal AO pedicle screws (140 in the thoracic spine and 508 in the lumbar spine) performed by one surgical team to treat 91 patients with spinal problems, were reviewed. The spinal pathology consisted of: scoliosis (34 patients), degenerative lower lumbar spinal disease (25 patients), neoplastic spinal disease (11 patients), thoracic kyphosis (8 patients), spinal fractures (7 patients), lumbo-sacral spondylolisthesis (3 patients), and osteomyelitis (3 patients). Intraoperative complications were: screw misplacement (n = 3), nerve root impingement (n = 1), cerebrospinal fluid leak (n = 2) and pedicle fracture (n = 2). Postoperative complications were; deep wound infection (n = 4), screw loosening (n = 2) and rod-screw disconnection (n = 1). The conclusion was that pedicle screw fixation has an acceptable complication rate and neurological injury during this procedure is unlikely.     

Parity as a risk factor for cancer cervix

PURPOSE: To analyze the likelihood of perioperative transfusion using the data of the abstracted patient discharge records. MATERIAL AND METHODS: It was studied the data of the records of the pediatric patients in whom were done surgical procedures for 1996. The abstracted patient discharge records are codified according the ICD-9-CM codes. RESULTS: 1,166 pediatric patients were operated, of whom were transfused 25 (2.1%). The transfusion rate was higher in patients less than 3 years old, who were operated with three o more surgical procedures simultaneously, who were admitted newly after the admittance here studied, and patients operated of spine, dorsolumbar spine, pharynx, thorax and mediastinum, central nervous system, colon, vessels and hip. CONCLUSIONS: Given the variability of the transfusion rate, to know it will allow a better planning of the surgical transfusions, the policy of the hospital blood bank and to increase the information to patient about the risk of the elective surgery.     

Molecular genetics of alpha-L-fucosyltransferase genes (H, Se, Le, FUT4, FUT5 and FUT6)

The records of 1018 patients with low back pain in a tertiary spine referral practice were reviewed. One hundred thirty-nine out of 1018 (13.6%) underwent technetium-99m planar bone scanning as part of their investigation. Seventy-three out of 139 scans (52%) showed increased uptake in some area, but only 27 out of 139 (19.4%) showed increased uptake specifically in the low back. Scans consistently yielded no findings with reference to the back when the prescan diagnosis was spinal stenosis, lumbar pain syndrome, herniated nucleus pulposus, or postlaminectomy syndrome. Some scans gave positive findings in patients with a diagnosis of degenerative disc disease, pseudarthrosis, spondylolisthesis, fracture, infection, metabolic disorder, or tumor. Positive scans were generally obtained early after presentation (within 3 months) and negative scans obtained later (after 6 months), suggesting that clinical suspicion is still the main indication for early scanning. Planar bone scanning was helpful in both diagnosis and therapeutic decision-making in many conditions.     

Defects of pars interarticularis in athletes: a protocol for nonoperative treatment

The purpose of this study was to report the results of a specific treatment protocol for athletes with spondylolysis or spondylolisthesis of the lumbar spine. A retrospective study with recent follow-up was performed on 82 patients treated with restriction of activity, bracing, and physical therapy. All of the patients were involved in sports at first onset of symptoms. Sixty-six patients were boys and 16 were girls. Activities involving repetitive hyperextension and/or extension rotation of the lumbar spine were described as painful in 98% of the patients. Of the 62 patients with spondylolysis, 53 (85%) had an L5 defect and nine (15%) an L4 defect (90% of these 62 patients' defects were located in the most caudad mobile vertebra). Thirty-seven patients had bilateral pars defects, and 25 had unilateral defects. Eight patients had normal roentgenograms, but these eight had abnormal bone scans. Nine patients with spondylolysis underwent posterolateral fusion. Average follow-up was 4.2 years. Fifty-two (84%) had excellent results, eight had good results, and two had fair results. Twenty patients had a spondylolisthesis: 12 were grade I, six were grade II, and two were grade III. Twelve patients (60%) required surgery; 9 had excellent results, one had good results, one had a fair result, and one had a poor result. Pars defects must be suspected in the differential of low back pain in young athletes. Oblique radiographs are frequently diagnostic; however, if the history and examination are suggestive despite normal plain films, a bone scan should be obtained. Nonoperative management of pars defects is frequently successful.(ABSTRACT TRUNCATED AT 250 WORDS)     

Gynaecological examination: a teaching package integrating assessment with learning (693)

Race and gender are important determinants of certain clinical outcomes in cardiovascular disease. To examine the influence of race and gender on care process, resource use, and hospital-based case outcomes for patients with congestive heart failure (CHF), we obtained administrative records on all 1995 New York State hospital discharges assigned ICD-9-CM codes indicative of this diagnosis. The following were compared among black and white women and men: demographics, comorbid illness, care processes, length of stay (LOS), hospital charges, mortality rate, and CHF readmission rate. We identified 45,894 patients (black women, 4,750; black men, 3,370; white women, 21,165; white men, 16,609). Blacks underwent noninvasive cardiac procedures more often than whites; procedure and specialty use rates were lower among women than among men. After adjusting for other patient characteristics and hospital type and location, we found race to be an important determinant of LOS (black, 10.4 days; white, 9.3 days; p = 0.0001), hospital charges (black, $13,711; white, $11,074; p = 0.0001), mortality (black-to-white odds ratio = 0.832; p = 0.003), and readmission (black-to-white odds ratio = 1.301; p = 0.0001). Gender was an important determinant of LOS (women, 9.8 days; men, 9.2 days; p = 0.0001), hospital charges (women, $11,690; men, $11,348; p = 0.02), and mortality (women-to-men odds ratio = 0.878; p = 0.0008). We conclude that race and gender influence care process and hospital-based case outcomes for patients with CHF.     

Internal fixation of the thoracic and lumbar spine using Roy-Camille plates

Thirty patients underwent fixation of the thoracic and lumbar spine from 1986 to 1990 using the Roy-Camille pedicular screw fixation system. The spine was stabilized for a variety of pathologic entities including fracture, tumor, spondylolisthesis, postlaminectomy instability, and pseudarthrosis. All but one patient obtained solid fusion based on radiographic and clinical criteria with an average follow up of 19.5 months. All patients reported subjective improvement in preoperative pain levels. There were no neurologic complications associated with the surgical procedure. Roy-Camille plate fixation appears to offer a stable surgical construct in the treatment of thoracic and lumbar spine instability.     

Spinal problems in mucopolysaccharidosis I (Hurler syndrome)

Bone-marrow transplantation has increased the survival of patients with mucopolysaccharidosis-I. We describe the spinal problems and their management in 12 patients with this disorder who have been followed up for a mean of 4.5 years since transplantation. High lumbar kyphosis was seen in ten patients which was associated with thoracic scoliosis in one. Isolated thoracic scoliosis was seen in another. One patient did not have any significant problems in the thoracic or lumbar spine but had odontoid hypoplasia, which was also seen in three other children. Four of the eight patients in whom MRI of the cervical spine had been performed had abnormal soft tissue around the tip of the odontoid. Neurological problems were seen in two patients. In one it was caused by cord compression in the lower dorsal spine 9.5 years after posterior spinal fusion for progressive kyphosis, and in the other by angular kyphosis with thecal indentation in the high thoracic spine associated with symptoms of spinal claudication.     

Formal descriptions and adaptive mechanisms for changes in controlled medical vocabularies

Standard controlled medical vocabularies are typically based on a coding scheme, while medical informatics applications tend to have a more formal conceptual foundation. When such applications attempt to use data coded with standard vocabularies, problems can arise when the standard vocabulary changes over time. A formal taxonomy is presented for describing the semantic changes which can occur in a vocabulary, such as simple addition, refinement, precoordination, disambiguation, redundancy, obsolescence, discovered redundancy, major name changes, minor name changes, code reuse, and changed codes. The taxonomy is described that used to effect change in one concept-based vocabulary (the Medical Entities Dictionary), and the utility of the approach is demonstrated by applying it to the changes appearing in the 1994 release of the International Classification of Diseases, Ninth Edition, with Clinical Modifications (ICD-9-CM).     

Dural tears secondary to operations on the lumbar spine. Management and results after a two-year-minimum follow-up of eighty-eight patients

We reviewed the results of acute management of patients who had sustained a dural tear during an operation on the lumbar spine, and we attempted to determine the long-term sequelae of this complication. In the five years from July 1989 to July 1994, 641 consecutive patients had a decompression of the lumbar spine, performed by the senior one of us; of these patients, eighty-eight (14 percent) sustained a dural tear, which was repaired during the operation. The duration of follow-up ranged from two to eight years (average, 4.3 years). Postoperative management consisted of closed suction wound drainage for an average of 2.1 days and bed rest for an average of 2.9 days. Of the eighty-eight procedures that resulted in a dural tear, forty-five were revisions; these revisions were performed after an average of 2.2 previous operations on the lumbar spine, all of which resulted in a scar adherent to the dura. Only eight patients had headaches related to the spinal procedure and photophobia in the postoperative period; these symptoms resolved in all but two patients, both of whom had had a revision operation. Each of the two patients had symptoms of a persistent leak of spinal fluid and needed a reoperation for repair. Overall, seventy-six patients had a good or excellent result and twelve had a poor or satisfactory result with some residual back pain. One patient had arachnoiditis, and another had symptoms of viral meningitis one month postoperatively. A dural tear that occurs during an operation on the lumbar spine can be treated successfully with primary repair followed by bed rest. Such a tear does not appear to have any long-term deleterious effects or to increase the risk of postoperative infection, neural damage, or arachnoiditis. Closed suction wound drainage does not seem to aggravate the leak and can be used safely in the presence of a dural repair.     

Observer variation in plain radiography of the lumbosacral spine

In this study, interobserver and intraobserver variations in the interpretation of plain radiographs of the lumbosacral spine were evaluated. Three radiologists independently interpreted the radiographs from 200 consecutive outpatients, aged 13-93 years, mostly referred from general practitioners. Interobserver agreement was best for vertebral fractures, osteopenia, spondylolisthesis at L5-S1, lumbosacral junctional vertebra, reduced disc height at L4-S1 and osteophytes at L2-S1 (kappa 0.61-0.95), and poorest for spina bifida of S1, degenerative spondylolisthesis and facet joint arthrosis at T12-L4, sacroiliac joint arthrosis, narrow central spinal canal, film quality, and for decisions concerning evaluation of facet joints and spinal canal (kappa < 0.34). For several diagnoses, the number of abnormal findings differed significantly between observers (p < 0.05, McNemar's test), indicating different diagnostic thresholds. Intraobserver agreement in 36 reevaluated patients was fair to excellent for almost all variables (kappa > 0.46). Although some diagnoses related to low back pain were quite consistently evaluated, the substantial disagreement on many findings should alert clinicians and radiologists against overestimating the validity and usefulness of the examinations. To improve diagnostic consistency, it is important to reduce variation caused by different thresholds for abnormality.     

Microdecompression and uninstrumented single-level fusion for spinal canal stenosis with degenerative spondylolisthesis

STUDY DESIGN: A retrospective review was completed on 21 patients who had a "least invasive" (one or two level) microdecompression and uninstrumented single-segment lumbar fusion for spinal canal stenosis with degenerative spondylolisthesis. OBJECTIVE: To determine whether a "least invasive" approach to lumbar spinal canal stenosis and degenerative spondylolisthesis would yield acceptable results. SUMMARY OF BACKGROUND DATA: The prevailing surgical technique for symptomatic spinal canal stenosis with degenerative spondylolisthesis is a wide midline decompression and instrumented fusion. METHODS: On an average of 38 months postoperatively, 21 patients were personally assessed on four scores: 1) their overall satisfaction with the outcome of surgery, 2) an analog back and leg pain scale, 3) a functional evaluation scale, and 4) Ferguson (upshot) anterior-posterior lumbosacral and lateral flexion-extension radiographs. RESULTS: The overall satisfactory outcome on all four scales was 16 (76%) of 21. Twenty of twenty-one patients had relief of their claudicant leg pain; the overall fusion rate was 18 (86%) of 21. Two of three patients with a pseudarthrosis had a successful outcome on the patient-oriented outcome (1, 2, and 3) scales (excluding the radiograph scale), and one was a failure. One patient with a solid fusion was a failure because of continuing back pain. One patient with a solid fusion was a failure because of continuing leg pain. The overall satisfactory outcome on the nonradiographic scales was 18 of 21, for an 86% patient satisfaction rate. CONCLUSIONS: In this retrospective study, a "least invasive" surgical approach to lumbar degenerative spondylolisthesis with spinal canal stenosis causing claudicant leg pain produced acceptable results.     

Complications of CT-guided biopsy of the spine and sacrum

This study reviews the results of 94 computed tomography (CT)-guided Craig needle biopsies of the spine and sacrum performed at one center. An indication for biopsy in this study was prompted by abnormal findings identified by one or more of the following diagnostic modalities: radiography, CT, magnetic resonance imaging (MRI), or bone scanning. These patients then underwent CT-guided Craig needle biopsy of the spine and sacrum for further evaluation. There were 1 biopsy of the cervical spine, 19 of the thoracic spine, 66 of the lumbar spine, and 8 of the sacrum. Biopsy sensitivity was 94.5% and specificity was 96.8%. This accuracy compared with other diagnostic modalities showed biopsy to be the gold standard for diagnosis of spine or sacral lesions. Of the 94 cases reviewed, 6 complications were noted. All complications were acute in nature and included 1 aortic puncture, 2 psoas punctures with associated psoas hematomas, 1 biopsy of an incorrect level, and 2 aborted procedures secondary to patient discomfort. No infections or neurological sequelae were seen. Although the benefits of CT-guided biopsy over open biopsy have been shown previously, this review demonstrates it is not without significant risk.