Accuracy of implanted port placement with the use of the electromagnetic CathTrack catheter locator system

PURPOSE

To test whether an electromagnetic guidance system such as CathTrack would allow long-term central venous access devices to be reliably placed at a decreased cost and without radiation exposure to patients and staff. The following study was undertaken to verify accuracy of the CathTrack system for catheter placement and to develop guidelines for its use.

METHODS

Twenty-nine consecutive patients were prospectively enrolled in the study and taken to the operating room for implantation of a permanent central venous access port. By protocol, the CathTrack system was used to guide initial catheter positioning using the center of the third intercostal space along the right sternal border as the desired external target. Fluoroscopy was then used to visualize tip position and relocate the catheter tip to the exact position desired by the surgeon.

RESULTS

Catheter placement using the CathTrack system was successfully accomplished in 27 out of 29 patients. In two instances CathTrack was abandoned and fluoroscopy utilized because of difficulty in threading the initial guidewire into the superior vena cava.

CONCLUSION

The CathTrack electromagnetic locator system can be used to reliably position catheters for the establishment of long-term central venous access. Decreased cost and elimination of radiation exposure are distinct advantages of this system over fluoroscopy.

Alternatives to HIV-1 RNA concentration and CD4 count to predict mortality in HIV-1-infected children in resource-poor settings

Cheaper, simpler alternatives to CD4 lymphocyte count and HIV-1 RNA detection for assessing the prognosis of HIV-1 infection are needed for resource-poor settings. However, little is known about the predictive value of alternative assays, in particular in children. We assessed the prognostic value of total lymphocyte count, immune complex-dissociated p24 antigen, white blood cell count, packed-cell volume (haematocrit), and serum albumin for mortality in 376 HIV-1-infected, mainly African-American or Hispanic children enrolled during March, 1988 to January, 1991. In a Cox proportional hazards model, including all assay-alternatives to CD4 and RNA, total lymphocyte count (p<0.0001) and serum albumin (p=0.0107) independently predicted mortality. Further assessment of these markers is warranted in resource-poor settings.

Efficacy of zidovudine and human immunodeficiency virus (HIV) hyperimmune immunoglobulin for reducing perinatal HIV transmission from HIV-infected women with advanced disease: results of Pediatric AIDS Clinical Trials Group protocol 185

Pediatric AIDS Clinical Trials Group protocol 185 evaluated whether zidovudine combined with human immunodeficiency virus (HIV) hyperimmune immunoglobulin (HIVIG) infusions administered monthly during pregnancy and to the neonate at birth would significantly lower perinatal HIV transmission compared with treatment with zidovudine and intravenous immunoglobulin (IVIG) without HIV antibody. Subjects had baseline CD4 cell counts </=500/microL (22% had counts <200/microL) and required zidovudine for maternal health (24% received zidovudine before pregnancy). Transmission was associated with lower maternal baseline CD4 cell count (odds ratio, 1.58 per 100-cell decrement; P=.005; 10.0% vs. 3.6% transmission for count <200 vs. >/=200/microL) but not with time of zidovudine initiation (5.6% vs. 4.8% if started before vs. during pregnancy; P=. 75). The Kaplan-Meier transmission rate for HIVIG recipients was 4. 1% (95% confidence interval, 1.5%-6.7%) and for IVIG recipients was 6.0% (2.8%-9.1%) (P=.36). The unexpectedly low transmission confirmed that zidovudine prophylaxis is highly effective, even for women with advanced HIV disease and prior zidovudine therapy, although it limited the study's ability to address whether passive immunization diminishes perinatal transmission.

Serum vitamin A concentrations in a North American cohort of human immunodeficiency virus type 1-infected children. National Institute of Child Health and Human Development Intravenous Immunoglobulin Clinical Trial Study Group

BACKGROUND

Vitamin A deficiency is associated with increased risks of vertical transmission of HIV-1 (HIV) and of disease progression and mortality among HIV-infected adults. The objectives of the study were to describe serum vitamin A concentrations among HIV-infected children in the National Institute of Child Health and Human Development IVIG Clinical Trial, to examine changes in vitamin A concentrations and to investigate the relationships between vitamin A concentrations and morbidity and mortality.

METHODS

Blood was collected from children at baseline and at 3-month intervals throughout the study. Serum samples were stored at -70 degrees C at a central repository until retrieved for vitamin A assay. Samples were hexane-extracted and assayed by high performance liquid chromatography. The rate of change in vitamin A concentrations, calculated by fitting a linear regression model, was expressed as micrograms/dl/year.

RESULTS

The median vitamin A concentration at baseline (n = 207 children) was 31.0 microg/dl [range, undetectable (< 10 microg/dl) to 98 microg/dl]. The rate of change in vitamin A concentrations (n = 180 children) did not vary significantly by any factor other than baseline vitamin A concentration. Baseline vitamin A concentration was not associated with morbidity (incidence of infections, growth failure, CD4+ percent decline below 15%, increases in serum HIV RNA concentrations above either 10(5) or 10(6) copies/ml or acute care hospitalization). Neither baseline vitamin A concentration nor the rate of change of vitamin A concentrations was associated with mortality.

CONCLUSIONS

Among these North American children with relatively normal vitamin A concentrations, vitamin A was not observed to be associated with morbidity or mortality.

Serum HIV-1 p24 antibody, HIV-1 RNA copy number and CD4 lymphocyte percentage are independently associated with risk of mortality in HIV-1-infected children. National Institute of Child Health and Human Development Intravenous Immunoglobulin Clinical Trial Study Group

OBJECTIVE

The role of HIV-1 antibody in modulating disease progression must be assessed in the context of other immune and viral load markers. We evaluated the association between HIV-1 p24 antibody, HIV-1 RNA, immune complex-dissociated (ICD) p24 antigen, CD4 cell percentage, and mortality in a cohort of 218 HIV-infected children enrolled in a trial of intravenous immunoglobulin prophylaxis of bacterial infections.

METHODS

CD4 cell percentage was measured and sera collected and stored at baseline and every 3 months on study (1988-1991). Stored sera were assayed for HIV-1 p24 antibody, HIV-1 RNA, and ICD p24 antigen. Mortality was recorded during the trial and updated through 1996 (mean total follow-up, 6.3 years).

RESULTS

Eighty-one (37%) children died; probability of mortality for children with baseline HIV-1 p24 antibody concentrations of undetectable (< 1), 1-4, 5-124, and > or = 125 reciprocal titer units (RTU) was 61, 50, 24, and 10%, respectively. A 3.5-fold increase in the relative risk (RR) of death [95% confidence interval (CI), 2.2-5.5] was observed among children with baseline HIV-1 p24 antibody concentration < 5 RTU compared with > or = 5 RTU. In multivariate analyses, p24 antibody, HIV-1 RNA, and CD4 cell percentage but not ICD p24 antigen were independently associated with mortality; the RR of death increased by 1.7 (95% CI, 1.3-2.1) for each log10 decrement in baseline HIV-1 p24 antibody.

CONCLUSIONS

HIV-1 p24 antibody, HIV-1 RNA and CD4 cell percentage independently predict mortality amongst infected children. Whereas CD4 cell percentage provides an estimate of the general degree of immune suppression, HIV-1 p24 antibody could provide an easily obtained, inexpensive assessment of CD4 cell function and could augment prognostic information provided by CD4 cell count and viral load for clinical management of infected children.

Characteristics of acute pneumonia in human immunodeficiency virus-infected children and association with long term mortality risk. National Institute of Child Health and Human Development Intravenous Immunoglobulin Clinical Trial Study Group

OBJECTIVE

To describe the epidemiologic, clinical, radiologic, laboratory and treatment characteristics of acute pneumonia and its association with mortality in HIV-infected children.

METHODS

Data were collected during a trial of intravenous immunoglobulin (IVIG) for infection prophylaxis (1988 to 1991); CD4+ percentage was measured and HIV RNA was assessed on stored sera collected at baseline and every 3 months. Mortality was recorded during the trial and updated through 1996. All reported physician-diagnosed pneumonia episodes underwent blinded review for trial endpoint classification as acute (new radiologic findings and presence of clinical symptoms) or nonacute.

RESULTS

On blinded clinical trial endpoint review of all reported pneumonia episodes (n = 281), only 47% were classified as acute. One hundred thirty-one episodes of acute pneumonia were reported in 93 children (47 in 31 IVIG and 84 in 62 placebo patients, P < 0.01). The incidence of acute pneumonia was 24 episodes per 100 patient years. Findings associated with an acute bacterial process were uncommon (leukocytosis > or =15000/mm3 in 21% and fever > or =103 degrees F in 32% of episodes). Multiple acute episodes occurred in 34% of the children and were associated with increased risk of mortality in a univariate analysis (risk ratio, 2.1; 95% confidence interval, 1.3 to 3.4, P = 0.002), but in a multivariate model only baseline HIV RNA copy number and CD4+ percentage remained independently associated with mortality (relative risk, 2.0 and 1.4, respectively, P < 0.001).

CONCLUSION

Acute pneumonia was a common occurrence in HIV-infected children and was associated with long term mortality risk. Multiple episodes of acute pneumonia likely represent a marker of progressive disease and immunologic dysfunction rather than being causally associated with increased long term mortality.

The relationship between serum human immunodeficiency virus type 1 (HIV-1) RNA level, CD4 lymphocyte percent, and long-term mortality risk in HIV-1-infected children. National Institute of Child Health and Human Development Intravenous Immunoglobulin Clinical Trial Study Group

Association of human immunodeficiency virus type 1 (HIV-1) RNA level, CD4 cell percent, and mortality was examined in stored sera from 254 infected children in an intravenous immunoglobulin infection prophylaxis trial. Ninety-two children (36.2%) died (41 during the study, 51 during long-term follow-up). The geometric mean baseline HIV-1 RNA level was 104,626 copies/mL, and the mean CD4 cell percent was 25%. Relative risk of death (RR) was 2.1 if the baseline RNA level was >100,000 copies/mL (95% confidence interval [CI], 1.4-3.0) and was 3.0 if the baseline CD4 cell percent was <15% (95% CI, 2.2-4.0). If RNA levels increased after baseline, the RR was 1.8 (95% CI, 1.3-2.6), and if the CD4 cell percent dropped to <15%, the RR was 2.8 (95% CI, 1.6-4.9). In a multivariate model, both baseline RNA level and CD4 cell percent were independently associated with mortality risk. In a time-dependent model, the RR per log10 increase in HIV-1 RNA copy numbers was 2.8 (95% CI, 2.1-3.6) and per 5 percentage point decrement in CD4 cell percent was 1.3 (95% CI, 1.2-1.5). Both variables should be considered for in decision-making regarding therapy and evaluation of antiretroviral response.

Changes in CD4+ and CD8+ cell levels during pregnancy and post partum in women seropositive and seronegative for human immunodeficiency virus-1

OBJECTIVE

Our objective was to examine changes in CD4+ and CD8+ cell levels during pregnancy and post partum and to determine whether they differ for human immunodeficiency virus-1-seropositive and seronegative women.

STUDY DESIGN

A total of 192 human immunodeficiency virus-1-seropositive and 148 seronegative women enrolled in a study of mother-to-child transmission of human immunodeficiency virus-1 who had at least two lymphocyte subset measurements performed during pregnancy or post partum were included in this analysis. Mixed effects repeated-measures models were developed to examine changes in CD4+ and CD8+ cell levels during this period.

RESULTS

Consistent with prior reports that CD4+ cell levels decline during pregnancy and return to normal post partum, percent levels increased between the third trimester and 12 months post partum among human immunodeficiency virus-seronegative women (1.98%, p = 0.04). However, CD4+ levels declined steadily during pregnancy and post partum among seropositive women (-1.57%, p = 0.02 between the third trimester and 12 months post partum; =2.65%, p = 0.0004 between 2 and 24 months post partum). The percent CD8+ cell levels increased at or near delivery and declined to baseline between 2 and 6 months post partum in both seronegative and seropositive women, although only the declines were statistically significant in both groups (-2.66%, p = 0.004; and -2.02%, p = 0.02, respectively).

CONCLUSIONS

The percent CD4+ cell levels declined steadily during pregnancy and post partum among human immunodeficiency virus-seropositive women, indicating that human immunodeficiency virus disease continues to progress during this period. The percent CD8+ cell levels increased at or near delivery and declined to baseline post partum in both seronegative and seropositive women. These findings may have important clinical implications for both human immunodeficiency virus-infected and uninfected pregnant women.

Sinusitis in children infected with human immunodeficiency virus: clinical characteristics, risk factors, and prophylaxis. National Institute of Child Health and Human Development Intravenous Immunoglobulin Clinical Trial Study Group

The clinical presentation, radiological and laboratory evaluation, treatment, and risk factors of sinusitis in a cohort of 376 human immunodeficiency virus (HIV)-infected children from a placebo-controlled clinical trial of intravenous immunoglobulin (IVIG) as prophylaxis for infections were examined. Ninety-five episodes of sinusitis were described in 60 patients; one-third of the patients had two or more episodes. Sinusitis episodes were commonly associated with nonspecific, chronic symptoms (67.4%, persistent nasal discharge; 54.7%, nocturnal or persistent cough), whereas symptoms more specific to acute sinusitis were less frequent (17.9%, headache or facial pain; 9.5%, periorbital swelling; 25.3%, temperature of > or = 102 degrees F; 9%, total white blood cell count of > or = 15,000/mm3). The sinuses primarily involved were the maxillary sinus (85.9%) and the ethmoidal sinus (42.3%); 36% of episodes involved two or more sinuses. Preceding respiratory infections did not appear to increase the risk of sinusitis, and CD4+ lymphocyte counts in children with and without sinusitis did not differ. Neither monthly IVIG prophylaxis nor three times weekly trimethoprimsulfamethoxazole prophylaxis for Pneumocystis carinii pneumonia decreased the risk of sinusitis. Sinusitis in HIV-infected children is most often subacute and recurrent. Evaluations of new modalities for prophylaxis for sinusitis are needed.

Crossover of placebo patients to intravenous immunoglobulin confirms efficacy for prophylaxis of bacterial infections and reduction of hospitalizations in human immunodeficiency virus-infected children. The National Institute of Child Health and Human Development Intravenous Immunoglobulin Clinical Trial Study Group

After completion of a placebo-controlled trial of intravenous immunoglobulin (IVIG) infection prophylaxis, patients were offered open label IVIG and optional participation in a follow-up study. The purpose of the follow-up study was to evaluate the IVIG effect in original placebo recipients and longevity of IVIG benefit in original IVIG recipients. Of 212 human immunodeficiency virus-infected children on study at trial closure, 148 (67 of 98 (68%) placebo and 81 of 114 (71%) IVIG patients) received open label IVIG for a mean of 16 months. When open label IVIG was begun, 45% were receiving trimethoprim-sulfamethoxazole prophylaxis for Pneumocystis carinii pneumonia (43% of placebo and 47% of IVIG patients) and 54% were receiving zidovudine (55% of placebo and 53% of IVIG patients). In patients who received placebo during the original study, the rate of serious bacterial infections was significantly lower after change to open label IVIG (estimated 15.8 fewer episodes/100 patient years; 95% confidence interval, 3.2 to 28.5; P = 0.014). Similar findings were observed for minor bacterial infections (estimated 61.2 fewer/100 patient years; 95% confidence interval, 29.2 to 93.3; P < 0.001) and hospitalizations (estimated 43.7 fewer/100 patient years; 95% confidence interval, 27.7 to 59.6; P < 0.001). Decreases were observed whether or not trimethoprim-sulfamethoxazole prophylaxis was being given at the time open label IVIG was begun. In patients who received IVIG during the original study, no significant difference was seen in infections or hospitalizations after change to open label IVIG.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevention of wound infections. A case for closed suction drainage to remove wound fluids deficient in opsonic proteins

Fluids collecting in surgical wounds in both dogs and man have been shown to lose progressively the ability to opsonize bacteria for phagocytosis and killing of bacteria by normal neutrophils. Since the collection of fluids in potentially contaminated wounds also interferes with access of phagocytic cells to contaminating bacteria and provides a pablum for growth, their removal seems to be indicated to minimize the risk of infection. This can be accomplished easily and safely with the use of closed suction drainage as demonstrated in 100 patients undergoing bilateral nephrectomy, splenectomy, and renal transplantation.