Jeffrey S. Groeger

Multicenter outcome study of cancer patients admitted to the intensive care unit: a probability of mortality model.

PURPOSE To develop prospectively and validate a model for probability of hospital survival at admission to the intensive care unit (ICU) of patients with malignancy. PATIENTS AND METHODS This was an inception cohort study in the setting of four ICUs of academic medical centers in the United States. Defined continuous and categorical variables were collected on consecutive patients with cancer admitted to the ICU. A preliminary model was developed from 1,483 patients and then validated on an additional 230 patients. Multiple logistic regression modeling was used to develop the models and subsequently evaluated by goodness-of-fit and receiver operating characteristic (ROC) analysis. The main outcome measure was hospital survival after ICU admission. RESULTS The observed hospital mortality rate was 42%. Continuous variables used in the ICU admission model are PaO2/FiO2 ratio, platelet count, respiratory rate, systolic blood pressure, and days of hospitalization pre-ICU. Categorical entries include presence of intracranial mass effect, allogeneic bone marrow transplantation, recurrent or progressive cancer, albumin less than 2.5 g/dL, bilirubin > or = 2 mg/dL, Glasgow Coma Score less than 6, prothrombin time greater than 15 seconds, blood urea nitrogen (BUN) greater than 50 mg/dL, intubation, performance status before hospitalization, and cardiopulmonary resuscitation (CPR). The P values for the fit of the preliminary and validation models are .939 and .314, respectively, and the areas under the ROC curves are .812 and .802. CONCLUSION We report a disease-specific multivariable logistic regression model to estimate the probability of hospital mortality in a cohort of critically ill cancer patients admitted to the ICU. The model consists of 16 unambiguous and readily available variables. This model should move the discussion regarding appropriate use of ICU resources forward. Additional validation in a community hospital setting is warranted.

T2 magnetic resonance assay for the rapid diagnosis of candidemia in whole blood: A clinical trial

BACKGROUND Microbiologic cultures, the current gold standard diagnostic method for invasive Candida infections, have low specificity and take up to 2-5 days to grow. We present the results of the first extensive multicenter clinical trial of a new nanodiagnostic approach, T2 magnetic resonance (T2MR), for diagnosis of candidemia. METHODS Blood specimens were collected from 1801 hospitalized patients who had a blood culture ordered for routine standard of care; 250 of them were manually supplemented with concentrations from <1 to 100 colony-forming units (CFUs)/mL for 5 different Candida species. RESULTS T2MR demonstrated an overall specificity per assay of 99.4% (95% confidence interval [CI], 99.1%-99.6%) with a mean time to negative result of 4.2 ± 0.9 hours. Subanalysis yielded a specificity of 98.9% (95% CI, 98.3%-99.4%) for Candida albicans/Candida tropicalis, 99.3% (95% CI, 98.7%-99.6%) for Candida parapsilosis, and 99.9% (95% CI, 99.7%-100.0%) for Candida krusei/Candida glabrata. The overall sensitivity was found to be 91.1% (95% CI, 86.9%-94.2%) with a mean time of 4.4 ± 1.0 hours for detection and species identification. The subgroup analysis showed a sensitivity of 92.3% (95% CI, 85.4%-96.6%) for C. albicans/C. tropicalis, 94.2% (95% CI, 84.1%-98.8%) for C. parapsilosis, and 88.1% (95% CI, 80.2%-93.7%) for C. krusei/C. glabrata. The limit of detection was 1 CFU/mL for C. tropicalis and C. krusei, 2 CFU/mL for C. albicans and C. glabrata, and 3 CFU/mL for C. parapsilosis. The negative predictive value was estimated to range from 99.5% to 99.0% in a study population with 5% and 10% prevalence of candidemia, respectively. CONCLUSIONS T2MR is the first fully automated technology that directly analyzes whole blood specimens to identify species without the need for prior isolation of Candida species, and represents a breakthrough shift into a new era of molecular diagnostics. CLINICAL TRIALS REGISTRATION NCT01752166.

A prospective, randomized evaluation of the effect of silver impregnated subcutaneous cuffs for preventing tunneled chronic venous access catheter infections in cancer patients.

ObjectiveThis study was performed to evaluate the effect of a silver-impregnated cuff on the incidence of catheter-related bacteremia/fungemia or tunnel tract infection in cancer patients with chronic dual-lumen tunneled venous access catheters. Summary Background DataInfection is a frequent and potentially life-threatening complication of tunneled chronic cuffed silastic central venous access catheters in cancer patients. Recent experience with antimicrobial silver-impregnated cuffs placed on nontunneled percutaneously inserted central venous catheters suggests that such a cuff may render the catheter less prone to infection. MethodsThe authors prospectively randomized 200 cancer patients to receive either a dual-lumen 10 French tunneled cuffed silastic central venous access catheter or the same catheter with a second more proximal subcutaneous silver-impregnated cuff. All patients then were followed prospectively for infectious morbidity until the device was removed or the patient died. ResultsThe hazard rate for infection/day (95% confidence limits) was 0.0022 (0.0015 to 0.0030) for standard catheters compared with 0.0027 (0.0019 to 0.0037) for catheters with silver-impregnated cuffs (p = not significant). Regression analysis of infection-free Interval of both catheter types shows no difference over the lifetime of catheter as well as the over the first 48 days after insertion. ConclusionsThe study indicated no effect of a silver-impregnated cuff in decreasing the incidence of catheter-related bacteremias/fungemias, tunnel infections, or the spectrum of causative microorganisms involved in cancer patients with tunneled chronic venous access catheters.

Transcutaneously Tunneled Central Venous Lines in Cancer Patients: An Analysis of Device-Related Morbidity Factors Based on Prospective Data Collection

AbstaractBackground: Long-term transcutaneous tunneled central venous catheters are frequently placed in cancer patients, accounting for significant costs and morbidity. Factors influencing outcome, though, are poorly studied. Methods: Between June 1991 and June 1993, 923 central venous tunneled catheters were placed in 791 patients at Memorial Sloan-Kettering Cancer Center. Placement-, device-, and patient-related parameters were charted prospectively (median follow-up: 120 days) and correlated to device-specific outcome events. Results: Median patient age was 28.5 years (range: 0.025 - 84.5). Disease distribution included hematologic malignancies (64.7%), solid tumors (30.4%), and others (4.9%). Primary indications for line access included chemotherapy (72.8%), bone marrow transplantation (18.7%), total parenteral nutrition (6.4%), and drug administration (2.1%). There were 11 insertion complications (1.2%), including insertion failure (n 5 6), hemorrhage (n 5 4), and malposition (n 5 1). Subsequent to placement, a proven or suspected device-specific complication occurred in 540 lines (58.5%). Per 10,000 catheter days, there were 17.6 infection episodes, 8.1 thrombotic complications, 6.9 instances of catheter breakage, 3.5 accidental or inadvertent cases of displacement, and 0.6 device leaks. Reasons for line removal or other termination of follow-up were patient’s death (32.1%), treatment end (28%), infection (19.6%), suspected infection (6.3%), displacement (6.8%), thrombosis (3.1%), leak (1%), and others (3.1%). Median device-specific duration was 365 days, compared with a median complication-free device-specific duration of 167 days (P,0.0001), reflecting a highly significant device salvage rate after complications. Catheter tip position emerged as the dominant independent prognostic factor for reduced device-specific duration or complication-free device-specific duration. Conclusions: Transcutaneous tunneled central venous lines can be placed safely, with a considerable incidence of subsequent device-specific complications, but a high salvage rate. Factors determining outcome are related to device placement, as well as the patient’s disease status. In this study, patients alive 90 days after catheter placement had a 37% chance for a device complication, with a 20% chance for device loss. Future analyses of intermediate-term intravenous access should employ the measurement of device-specific outcome as a reference parameter to assess clinical results.

Naloxone in septic shock.

Abstract Naloxone, 0.3 mg/kg of a 10 mg/ml solution, was administered as a single bolus to patients in septic shock if their systolic blood pressure (BP) was less than 100 mm Hg or MAP less than 70 mm Hg with evidence of renal or cerebral hypoperfusion. Patients with chronic or acute (less than 12 h) administration of narcotics were excluded. Ten patients received naloxone; 5 patients had significant increases in blood pressure; 5 had no response. Maximal response in BP occurred by 15 min, and lasted 45-165 min. Responders could not be separated by nonresponders by analysis of baseline, hemodynamics, or prior steroid therapy; nonresponders were hemodynamically compromised greater than 24 h; responders less than or equal to 8. Two patients in each group were chronically on high-dose steroids and responded to a 2nd smaller dose of naloxone when effects of initial bolus had ended. Naloxone, 0.3 mg/kg, can reverse endorphin-mediated hypotension in acute septic shock in patients who have received chronic steroid therapy.

A prospective analysis of vascular access device-related infections in children

To identify significant predictors of device-related infections, we performed a prospective, nonrandomized analysis of our experience with vascular access devices over a 2-year period in a pediatric oncology population. Variables analyzed included: (1) age at placement, (2) sex, (3) underlying disease, (4) type of device used (catheter v port), and (5) total white blood cell count at placement. Quantitative microbiologic criteria were used for diagnosis of bacteremia while clinical and microbiologic criteria were used in diagnosis of tunnel/port/site infections. During the study period a total of 351 devices, comprising 78,159 days in situ, were placed and data for univariate and multivariate analysis were available on 271 (77%). The mean age at placement was 7.2 +/- 4.7 years for catheters and 9.5 +/- 4.8 years for implantable devices (P less than or equal to .01). Significant predictors of device-related infections in univariate analysis were type of device (P less than or equal to .0001) and age (P less than or equal to .002). External catheters and age less than or equal to 7 years were associated with increased risk of infection. Underlying disease had a marginal effect on the infection rate (P = .08). In multivariate analysis, device type (P less than or equal to .0001) and age (P less than or equal to .002) continued to affect infections, whereas underlying disease demonstrated only a borderline effect (P = .14). We conclude that device type and age significantly affect the rate of device-related infections. These data support increased use of implantable devices in pediatric oncology patients.

A prospective randomized double-blind trial of bolus urokinase in the treatment of established Hickman catheter sepsis in children

BACKGROUND The incidence of Hickman catheter sepsis is 10% to 40%, with resultant catheter loss in one third of infections. Urokinase causes dissolution of colonized intracatheter fibrin thrombi and may improve salvage. STUDY AIMS To evaluate the efficacy of 12-hour-interval slow-push urokinase infusion in addition to standard antibiotic therapy in the treatment of catheter sepsis in a pediatric oncology population. METHODS A two-arm randomized double-blind trial was undertaken, with catheter salvage rate as the end point. Patients with Hickman catheter sepsis were randomized after culture data confirmed the diagnosis. The study drug was administered by a slow intravenous push and given at 12-hour intervals for a total of four doses. The catheters were aspirated after 1 hour. RESULTS AND CONCLUSIONS The trial was stopped after 41 patients were entered into the study; 18 patients received a placebo, and 23 received the urokinase. In the placebo group, six catheters were lost; in the urokinase group, eight were lost. The rate of bacterial clearance was equivalent for both. After administration of the study drug, each group had three episodes of fever and chills; two of these resulted in hypotension (one in each group). The authors conclude that slow-push urokinase infusion during established Hickman catheter sepsis does not result in improved catheter salvage or bacterial clearance. Slow intravenous push infusions in this setting may provoke hemodynamic instability even after initiation of antibiotics.

Capnography in mechanically ventilated patients

Capnography, the science of CO2 waveforms analysis, can play a role in the management of mechanically ventilated patients. Mass spectrometers are the devices most commonly used to collect sequentially and examine CO2 waveforms from multiple patients in the ICU or operating rooms. We present here a review of some clinical and technical problems, which may be resolved efficiently and expeditiously through the use of mass spectrometry and capnography. Mechanical failures, especially those that lead to rebreathing of exhaled gases, can be readily detected. The patients progress during weaning and the consequences of changes in mechanical assistance can be virtually and noninvasively determined. An expanded role of capnography in mechanically ventilated patients can increase the use of mass spectrometers in the ICU.

Indirect calorimetry in the mechanically ventilated patient

We used indirect calorimetry to measure oxygen consumption (&OV0312;o2) and carbon dioxide production in 29 mechanically ventilated patients. These data were compared to &OV0312;o2 measured simultaneously by a standard thermodilution technique. A good correlation was demonstrated between the methods, but &OV0312;o2 measured by indirect calorimetry was 15% higher than &OV0312;o2 measured by thermodilution.

Critical care for the severely ill head and neck patient

OBJECTIVE To delineate the frequency and causes of admission to a critical care environment for patients undergoing head and neck surgery at Memorial Sloan-Kettering Cancer Center. DESIGN Retrospective clinical investigation. SETTING Adult intensive care unit of a tertiary referral cancer center. PATIENTS All head and neck surgery patients admitted to the special care unit (SCU) of Memorial Sloan-Kettering Cancer Center between January 1, 1994 and December 31, 1995 were included in this study. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS The data collected included demographic, operative procedures, clinical, laboratory, and physiologic variables at time of SCU admission, at 24 hrs, as well as vital status at the time of discharge from the SCU and hospital. Other data collected were the need for mechanical ventilation and inotropic agents. During the period of January 1, 1994 through December 31, 1995, 37 (1.5%) of 2,346 patients undergoing head and neck surgical procedures required admission to the SCU. During the same period, six patients receiving medical treatment only for head and neck malignant disease were transferred to the SCU. These 43 admissions served as the basis for the study. The causes of admission to the SCU were pulmonary (15/43), cardiac (14/43), wound related (8/43), and other (15/43). The median length of stay in the SCU was 2 days, and the median hospitalization for patients requiring critical care services was 22 days. Seventy-four percent of patients requiring critical care services were eventually discharged to home. CONCLUSIONS Current preoperative evaluation, operative and anesthetic techniques, and perioperative care result in a low frequency of utilization of critical care services by patients undergoing head and neck surgery. There is no single identifiable cause of complications for patients after head and neck surgery leading to utilization of critical care services.