Murat Yilmaz - Academia.edu (original) (raw)

Papers by Murat Yilmaz

Research paper thumbnail of Risk factors for the development of acute lung injury in patients with septic shock: An observational cohort study

Critical Care Medicine, 2008

all 10 cities including the rural areas of the province of Kerman. All data were finally analyzed... more all 10 cities including the rural areas of the province of Kerman. All data were finally analyzed by SPSS software (version 11.5). Results On the basis of recorded statistical analysis, the mortality cases of human rabies in the province of Kerman during one decade was 10 persons (eight males and two females). One-half of them (50%) were bitten by dogs and the others (50%) by foxes. Among the reported deaths, 40% were from Kahnooj county (Jiroft region). The reported data indicated that 21,546 persons were bitten by animals during 10 years in the province of Kerman. The mean of age of the people who were bitten by dogs was 24.80 years (SD = ±14.6), while the mean age of the people who were bitten by foxes was 57.25 years (SD = ±1.50). There was a significant difference between the mean age of these two groups of the people (P < 0.05). The most frequent rate of injured people was reported in the age group 10-19 years old and the frequency rate of males (76.00%) was more than females (24.00%). Therefore, there was a statistically significant difference between males and females in this study (P < 0.01). About 60% of all persons that were bitten by animals were from rural areas and 40% of them were from urban areas (P < 0.05). Among the people who were bitten and injured by animals during one decade in the province of Kerman, 85.70% of them were not treated by the rabies prophylaxis treatment regimen. Among all of them who were bitten by animals, 50% were injured through hands and feet, 40%

Research paper thumbnail of Bedside quantification of dead-space fraction using routine clinical data in patients with acute lung injury: secondary analysis of two prospective trials

Critical Care, 2010

Introduction Dead-space fraction (Vd/Vt) has been shown to be a powerful predictor of mortality i... more Introduction Dead-space fraction (Vd/Vt) has been shown to be a powerful predictor of mortality in acute lung injury (ALI) patients. The measurement of Vd/Vt is based on the analysis of expired CO2 which is not a part of standard practice thus limiting widespread clinical application of this method. The objective of this study was to determine prognostic value of Vd/Vt estimated from routinely collected pulmonary variables. Methods Secondary analysis of the original data from two prospective studies of ALI patients. Estimated Vd/Vt was calculated using the rearranged alveolar gas equation: where is the estimated CO2 production calculated from the Harris Benedict equation, minute ventilation (VE) is obtained from the ventilator rate and expired tidal volume and PaCO2 from arterial gas analysis. Logistic regression models were created to determine the prognostic value of estimated Vd/Vt. Results One hundred and nine patients in Mayo Clinic validation cohort and 1896 patients in ARDS-net cohort demonstrated an increase in percent mortality for every 10% increase in Vd/Vt in a dose response fashion. After adjustment for non-pulmonary and pulmonary prognostic variables, both day 1 (adjusted odds ratio-OR = 1.07, 95%CI 1.03 to 1.13) and day 3 (OR = 1.12, 95% CI 1.06 to 1.18) estimated dead-space fraction predicted hospital mortality. Conclusions Elevated estimated Vd/Vt predicts mortality in ALI patients in a dose response manner. A modified alveolar gas equation may be of clinical value for a rapid bedside estimation of Vd/Vt, utilizing routinely collected clinical data.

Research paper thumbnail of Transfusion from male-only versus female donors in critically ill recipients of high plasma volume components

Critical Care Medicine, 2007

Hydrogen sulfide is produced endogenously by a variety of enzymes involved in cysteine metabolism... more Hydrogen sulfide is produced endogenously by a variety of enzymes involved in cysteine metabolism. Clinical data indicate that endogenous levels of hydrogen sulfide are diminished in various forms of cardiovascular diseases. The aim of the current study was to investigate the effects of hydrogen sulfide supplementation on cardiac function during reperfusion in a clinically relevant experimental model of cardiopulmonary bypass. Twelve anesthetized dogs underwent hypothermic cardiopulmonary bypass. After 60 minutes of hypothermic cardiac arrest, reperfusion was started after application of either saline vehicle (control, n = 6), or the sodium sulfide infusion (1 mg/kg/hour, n = 6). Biventricular hemodynamic variables were measured by combined pressure-volume-conductance catheters. Coronary and pulmonary blood flow, vasodilator responses to acetylcholine and sodiumnitroprusside and pulmonary function were also determined. Administration of sodium sulfide led to a significantly better recovery of left and right ventricular systolic function (P < 0.05) after 60 minutes of reperfusion. Coronary blood flow was also significantly higher in the sodium sulfide-treated group (P < 0.05). Sodium sulfide treatment improved coronary blood flow, and preserved the acetylcholine-induced increases in coronary and pulmonary blood (P < 0.05). Myocardial ATP levels were markedly improved in the sulfide-treated group. Thus, supplementation of sulfide improves the recovery of myocardial and endothelial function and energetic status after hypothermic cardiac arrest during cardiopulmonary bypass. These beneficial effects occurred without any detectable adverse hemodynamic or cardiovascular effects of sulfide at the dose used in the current study.

Research paper thumbnail of The Stability and Workload Index for Transfer score predicts unplanned intensive care unit patient readmission: Initial development and validation

Critical Care Medicine, 2008

Unplanned readmission of hospitalized patients to an intensive care unit (ICU) is associated with... more Unplanned readmission of hospitalized patients to an intensive care unit (ICU) is associated with a worse outcome, but our ability to identify who is likely to deteriorate after ICU dismissal is limited. The objective of this study is to develop and validate a numerical index, named the Stability and Workload Index for Transfer, to predict ICU readmission. In this prospective cohort study, risk factors for ICU readmission were identified from a broad range of patients&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; admission and discharge characteristics, specific ICU interventions, and in-patient workload measurements. The prediction score was validated in two independent ICUs. One medical and one mixed medical-surgical ICU in two tertiary centers. Consecutive patients requiring &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;24 hrs of ICU care. None. Unplanned ICU readmission or unexpected death following ICU dismissal. In a derivation cohort of 1,131 medical ICU patients, 100 patients had unplanned readmissions, and five died unexpectedly in the hospital following ICU discharge. Predictors of readmission/unexpected death identified in a logistic regression analysis were ICU admission source, ICU length of stay, and day of discharge neurologic (Glasgow Coma Scale) and respiratory (hypoxemia, hypercapnia, or nursing requirements for complex respiratory care) impairment. The Stability and Workload Index for Transfer score predicted readmission more precisely (area under the curve [AUC], 0.75; 95% confidence interval [CI], 0.70-0.80) than the day of discharge Acute Physiology and Chronic Health Evaluation III score (AUC, 0.62; 95% CI, 0.56-0.68). In the two validation cohorts, the Stability and Workload Index for Transfer score predicted readmission similarly in a North American medical ICU (AUC, 0.74; 95% CI, 0.67-0.80) and a European medical-surgical ICU (AUC, 0.70; 95% CI, 0.64-0.76), but was less well calibrated in the medical-surgical ICU. The Stability and Workload Index for Transfer score is derived from information readily available at the time of ICU dismissal and acceptably predicts ICU readmission. It is not known if discharge decisions based on this prediction score will decrease the number of ICU readmissions and/or improve outcome.

Research paper thumbnail of Toward the prevention of acute lung injury: Protocol-guided limitation of large tidal volume ventilation and inappropriate transfusion

Critical Care Medicine, 2007

We evaluated the effect of two quality improvement interventions (low tidal volume ventilation an... more We evaluated the effect of two quality improvement interventions (low tidal volume ventilation and restrictive transfusion) on the development of acute lung injury in mechanically ventilated patients. Observational cohort study. Three intensive care units in a tertiary academic center. We included patients who were mechanically ventilated for &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or =48 hrs excluding those who refused research authorization or had preexisting acute lung injury or pneumonectomy. Multifaceted interdisciplinary intervention consisting of Web-based teaching, respiratory therapy protocol, and decision support within computerized order entry. Of 375 patients who met the inclusion and exclusion criteria, 212 were ventilated before and 163 after the interventions. Baseline characteristics were similar between the two groups except for a lower frequency of sepsis (27% vs. 17%, p = .030), trend toward lower median glucose level (140 mg/dL, interquartile range 118-168 vs. 132 mg/dL, interquartile range 113-156, p = .096), and lower frequency of pneumonia (27% vs. 20%, p = .130) during the second period. We observed a large decrease in tidal volume (10.6-7.7 mL/kg predicted body weight, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001), in peak airway pressure (31-25 cm H2O, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001), and in the percentage of transfused patients (63% to 38%, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001) after the intervention. The frequency of acute lung injury decreased from 28% to 10% (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001). The duration of mechanical ventilation decreased from a median of 5 (interquartile range 4-9) to 4 (interquartile range 4-8) days (p = .030). When adjusted for baseline characteristics in a multivariate logistic regression analysis, protocol intervention was associated with a reduction in the frequency of new acute lung injury (odds ratio 0.21, 95% confidence interval 0.10-0.40). Interdisciplinary intervention effectively decreased large tidal volumes and unnecessary transfusion in mechanically ventilated patients and was associated with a decreased frequency of new acute lung injury.

Research paper thumbnail of Transfusion related acute lung injury in the critically ill: prospective nested case-control study

Rationale: Acute lung injury (ALI) that develops six hours after transfusion (TRALI) is the leadi... more Rationale: Acute lung injury (ALI) that develops six hours after transfusion (TRALI) is the leading cause of transfusion-related mortality. Several transfusion characteristics have been postulated as risk factors for TRALI, but the evidence is limited to retrospective studies.

Research paper thumbnail of Utility of transcranial doppler ultrasonography for confirmatory diagnosis of brain death: two sides of the coin

Transplantation, 2004

Although the clinical examination and documentation of the clinical signs of brain death are very... more Although the clinical examination and documentation of the clinical signs of brain death are very uniform, there are significant differences in the guidelines for using technical confirmatory tests to corroborate the clinical signs. The current study examined the utility of transcranial Doppler ultrasonography (TCD) for confirmation of brain death. After 19 patients were excluded from the study because of lack of bone window or because an apnea test could not be performed because of desaturation, 100 patients (61 patients with clinical brain death, and 39 control patients with Glasgow Coma Score&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;5) were included in the study. The following TCD findings were accepted as confirmatory of brain death when they were found bilaterally or in at least three different arteries for at least 3 minutes within the same examination: (1) brief systolic forward flow or systolic spikes and diastolic reverse flow, (2) brief systolic forward flow or systolic spikes and no diastolic flow, or (3) no demonstrable flow in a patient in whom flow had been clearly documented in a previous TCD examination. The sensitivity and specificity of the first TCD examination for confirmation of brain death were 70.5% and 97.4%, respectively. Eighteen patients with clinical brain death required repeat TCD examinations because of detection of forward systolo-diastolic flow or a diastolic to-and-fro flow pattern, which were not confirmatory for the diagnosis of brain death. Brain death was confirmed ultrasonographically in 12 of 18 patients in a second examination after 12.6 +/- 8.3 hours of clinical brain death, in 2 patients in a third TCD examination, and in 1 patient in a fourth examination. Three clinically brain-dead patients had died before the diagnosis was confirmed by repeat TCD examinations. The sensitivity of TCD reached 100% in our study population after the fourth examination. The sensitivity of TCD is increased with repeat examinations and should be repeated in cases in which systolo-diastolic forward flow is demonstrated after the first TCD. TCD may prolong or shorten the time to declaration of brain death. The necessity of demonstrating cerebral circulatory arrest in patients with clinical brain death is debatable.

Research paper thumbnail of Validation of an electronic surveillance system for acute lung injury

Intensive Care Medicine, 2009

Objective Early detection of acute lung injury (ALI) is essential for timely implementation of ev... more Objective Early detection of acute lung injury (ALI) is essential for timely implementation of evidence-based therapies and enrollment into clinical trials. We aimed to determine the accuracy of computerized syndrome surveillance for detection of ALI in hospitalized patients and compare it with routine clinical assessment. Design Using a near-real time copy of the electronic medical records, we developed and validated a custom ALI electronic alert (ALI “sniffer”) based on the European-American Consensus Conference Definition and compared its performance against provider-derived documentation. Patients and setting A total of 3,795 consecutive critically ill patients admitted to nine multidisciplinary intensive care units (ICUs) of a tertiary care teaching institution were included. Measurements and main results ALI developed in 325 patients and was recognized by bedside clinicians in only 86 (26.5%). Under-recognition of ALI was associated with not implementing protective mechanical ventilation (median tidal volumes of 9.2 vs. 8.0 ml/kg predicted body weight, P < 0.001). ALI “sniffer” demonstrated excellent sensitivity of 96% (95% CI 94–98) and moderate specificity of 89% (95% CI 88–90) with a positive predictive value ranging from 24% (95% CI 13–40) in the heart–lung transplant ICU to 64% (95% CI 55–71) in the medical ICU. Conclusions The computerized surveillance system accurately identifies critically ill patients who develop ALI syndrome. Since the lack of ALI recognition is a barrier to the timely implementation of best practices and enrollment into research studies, computerized syndrome surveillance could be a useful tool to enhance patient safety and clinical research.

Research paper thumbnail of Repeat Percutaneous Tracheostomy in the Neurocritically Ill Patient

Neurocritical Care, 2006

Introduction Percutaneous tracheostomy is a widely used and accepted method for long-term mechani... more Introduction Percutaneous tracheostomy is a widely used and accepted method for long-term mechanical ventilation and airway protection. Neurocritically ill patients sometimes require repeat tracheostomy, which is traditionally considered a relative contraindication for percutaneous procedure. The aim of this study was to determine the safety of repeat percutaneous tracheostomy in neurocritically ill patients with a history of previous tracheostomy. Methods In the 16-bed academic neurointensive care unit, we prospectively enrolled patients who needed new tracheostomy placement for airway protection or prolonged mechanical ventilation and had previously undergone percutaneous tracheostomy placement. We collected data on indications, procedure, periprocedural complications, and outcome of repeated tracheostomy. Results Between January 2001 and October 2005, we enrolled 12 consecutive patients (mean age 35.4±7.0 years) who underwent repeat percutaneous tracheostomy. Head injury was the most common underlying diagnosis (seven patients, 58%). Tracheostomy tube placement was easy and successful in all patients, and none of the patients needed conversion to surgical tracheostomy. In three patients, ultrasound-guided needle aspiration was used before the procedure to confirm the position of the trachea. No patients died or experienced serious complication related to the procedure. Two patients (17%) had a minor periprocedura bleeding, which was controlled with local compression. Long-term outcome was poor, with only two patients alive and off the ventilator at hospital discharge, both with serious disability. Conclusion Repeat percutaneous tracheostomy can be performed safely in neurocritically ill patients who have undergone previous tracheostomy.

Research paper thumbnail of The use of the laryngeal mask airway as an alternative to the endotracheal tube during percutaneous dilatational tracheostomy

Intensive Care Medicine, 2002

Objective: To evaluate the safety and efficiency of the use of the laryngeal mask airway (LMA) du... more Objective: To evaluate the safety and efficiency of the use of the laryngeal mask airway (LMA) during percutaneous dilatational tracheostomy under bronchoscopic guidance comparing with the ventilation via endotracheal tube (ET). Design and setting: Prospective, randomized clinical trial in the eight-bed general intensive care unit of a university hospital. Patients: 60 consecutive adult critically ill patients who required elective tracheostomy for a period of 12 months. Interventions: Patients were randomly assigned to ventilated via LMA (n=30 patients), and to ventilated via ET (n=30). Measurements and results: Blood samples for arterial blood gas analyses were taken before the procedure (first value) and just before the insertion of tracheostomy tube (second value). There was no significant difference in pH, PaO2, or PaCO2 between groups before the procedure. The operating time was significantly shorter in LMA group (4.5±0.8 min versus 5.9±1.4 min). Although the second PaCO2 values were higher than the first in both groups, the rise in was significantly higher in ET group (6.8±3.5 mmHg vs. 4.5±2.4 mmHg). Hypercarbia was noted in 10 patients (38.5%) in the LMA group and 17 (56.7%) in the ET group. The decrease in pH related to hypercarbia was noted in both groups, but it was more significant in the ET group (p<0.05). Conclusion: LMA is an effective and successful ventilatory device during percutaneous dilatational tracheostomy. It improves visualization of the trachea and larynx during fiberoptic-assisted percutaneous dilatational tracheostomy and prevents the difficulties associated with the use of ET such as cuff puncture, tube transection by the needle, and accidental extubation. The use of a bronchoscope and the puncture of the ET cuff cause major increases in PaCO2.

Research paper thumbnail of Device‐Associated Nosocomial Infection Rates in Turkish Medical‐Surgical Intensive Care Units

Infection Control and Hospital Epidemiology, 2006

Background: Routine surveillance of nosocomial infections has become an integral part of infectio... more Background: Routine surveillance of nosocomial infections has become an integral part of infection control and quality assurance in US hospitals. Methods: As part of the International Nosocomial Infection Control Consortium, we performed a prospective nosocomial infection surveillance cohort study in 5 adult intensive care units of 4 Mexican public hospitals using the Centers for Disease Control and Prevention National Nosocomial Infections Surveillance system definitions. Site-specific nosocomial infection rates were calculated. Results: The overall nosocomial infection rate was 24.4% (257/1055) and 39.0 (257/6590) per 1000 patient days. The most common infection was catheter-associated bloodstream infection, 57.98% (149/257), followed by ventilator-associated pneumonia, 20.23% (52/257), and catheter-associated urinary tract infection, 21.79% (56/257). The overall rate of catheter-associated bloodstream infections was 23.1 per 1000 device-days (149/6450); ventilator-associated pneumonia rate was 21.8 per 1000 device-days (52/2390); and catheter-associated urinary tract infection rate was 13.4 per 1000 device-days (56/4184).

Research paper thumbnail of The routine use of pediatric airway exchange catheter after extubation of adult patients who have undergone maxillofacial or major neck surgery: a clinical observational study

Critical Care, 2004

We conducted the present study to determine the usefulness of routinely inserting a pediatric air... more We conducted the present study to determine the usefulness of routinely inserting a pediatric airway exchange catheter (PAEC) before tracheal extubation of adult patients who had undergone maxillofacial or major neck surgery and have risk factors for difficult reintubation. Methods A prospective, observational and clinical study was performed in the 25-bed general intensive care unit of a university hospital. Thirty-six adult patients who underwent maxillofacial or major neck surgery and had risk factors for difficult reintubation were extubated after insertion of the PAEC. Results Four of 36 (11.1%) patients required emergency reintubation after 2, 4, 6 and 18 hours after tracheal extubation, respectively. Reintubation of these patients, which was thought to be nearly impossible by direct laryngoscopy, was easily achieved over the PAEC. Conclusion The PAEC can be a life-saving device during reintubation of patients with risk factors for difficult reintubation such as laryngeo-pharyngeal oedema due to surgical manipulation or airway obstruction resulting from haematoma and anatomic changes. We therefore suggest the routine use of the PAEC in patients undergoing major maxillofacial or major neck surgery.

Research paper thumbnail of Drama

Research paper thumbnail of Risk factors for the development of acute lung injury in patients with septic shock: An observational cohort study

Critical Care Medicine, 2008

all 10 cities including the rural areas of the province of Kerman. All data were finally analyzed... more all 10 cities including the rural areas of the province of Kerman. All data were finally analyzed by SPSS software (version 11.5). Results On the basis of recorded statistical analysis, the mortality cases of human rabies in the province of Kerman during one decade was 10 persons (eight males and two females). One-half of them (50%) were bitten by dogs and the others (50%) by foxes. Among the reported deaths, 40% were from Kahnooj county (Jiroft region). The reported data indicated that 21,546 persons were bitten by animals during 10 years in the province of Kerman. The mean of age of the people who were bitten by dogs was 24.80 years (SD = ±14.6), while the mean age of the people who were bitten by foxes was 57.25 years (SD = ±1.50). There was a significant difference between the mean age of these two groups of the people (P < 0.05). The most frequent rate of injured people was reported in the age group 10-19 years old and the frequency rate of males (76.00%) was more than females (24.00%). Therefore, there was a statistically significant difference between males and females in this study (P < 0.01). About 60% of all persons that were bitten by animals were from rural areas and 40% of them were from urban areas (P < 0.05). Among the people who were bitten and injured by animals during one decade in the province of Kerman, 85.70% of them were not treated by the rabies prophylaxis treatment regimen. Among all of them who were bitten by animals, 50% were injured through hands and feet, 40%

Research paper thumbnail of Bedside quantification of dead-space fraction using routine clinical data in patients with acute lung injury: secondary analysis of two prospective trials

Critical Care, 2010

Introduction Dead-space fraction (Vd/Vt) has been shown to be a powerful predictor of mortality i... more Introduction Dead-space fraction (Vd/Vt) has been shown to be a powerful predictor of mortality in acute lung injury (ALI) patients. The measurement of Vd/Vt is based on the analysis of expired CO2 which is not a part of standard practice thus limiting widespread clinical application of this method. The objective of this study was to determine prognostic value of Vd/Vt estimated from routinely collected pulmonary variables. Methods Secondary analysis of the original data from two prospective studies of ALI patients. Estimated Vd/Vt was calculated using the rearranged alveolar gas equation: where is the estimated CO2 production calculated from the Harris Benedict equation, minute ventilation (VE) is obtained from the ventilator rate and expired tidal volume and PaCO2 from arterial gas analysis. Logistic regression models were created to determine the prognostic value of estimated Vd/Vt. Results One hundred and nine patients in Mayo Clinic validation cohort and 1896 patients in ARDS-net cohort demonstrated an increase in percent mortality for every 10% increase in Vd/Vt in a dose response fashion. After adjustment for non-pulmonary and pulmonary prognostic variables, both day 1 (adjusted odds ratio-OR = 1.07, 95%CI 1.03 to 1.13) and day 3 (OR = 1.12, 95% CI 1.06 to 1.18) estimated dead-space fraction predicted hospital mortality. Conclusions Elevated estimated Vd/Vt predicts mortality in ALI patients in a dose response manner. A modified alveolar gas equation may be of clinical value for a rapid bedside estimation of Vd/Vt, utilizing routinely collected clinical data.

Research paper thumbnail of Transfusion from male-only versus female donors in critically ill recipients of high plasma volume components

Critical Care Medicine, 2007

Hydrogen sulfide is produced endogenously by a variety of enzymes involved in cysteine metabolism... more Hydrogen sulfide is produced endogenously by a variety of enzymes involved in cysteine metabolism. Clinical data indicate that endogenous levels of hydrogen sulfide are diminished in various forms of cardiovascular diseases. The aim of the current study was to investigate the effects of hydrogen sulfide supplementation on cardiac function during reperfusion in a clinically relevant experimental model of cardiopulmonary bypass. Twelve anesthetized dogs underwent hypothermic cardiopulmonary bypass. After 60 minutes of hypothermic cardiac arrest, reperfusion was started after application of either saline vehicle (control, n = 6), or the sodium sulfide infusion (1 mg/kg/hour, n = 6). Biventricular hemodynamic variables were measured by combined pressure-volume-conductance catheters. Coronary and pulmonary blood flow, vasodilator responses to acetylcholine and sodiumnitroprusside and pulmonary function were also determined. Administration of sodium sulfide led to a significantly better recovery of left and right ventricular systolic function (P < 0.05) after 60 minutes of reperfusion. Coronary blood flow was also significantly higher in the sodium sulfide-treated group (P < 0.05). Sodium sulfide treatment improved coronary blood flow, and preserved the acetylcholine-induced increases in coronary and pulmonary blood (P < 0.05). Myocardial ATP levels were markedly improved in the sulfide-treated group. Thus, supplementation of sulfide improves the recovery of myocardial and endothelial function and energetic status after hypothermic cardiac arrest during cardiopulmonary bypass. These beneficial effects occurred without any detectable adverse hemodynamic or cardiovascular effects of sulfide at the dose used in the current study.

Research paper thumbnail of The Stability and Workload Index for Transfer score predicts unplanned intensive care unit patient readmission: Initial development and validation

Critical Care Medicine, 2008

Unplanned readmission of hospitalized patients to an intensive care unit (ICU) is associated with... more Unplanned readmission of hospitalized patients to an intensive care unit (ICU) is associated with a worse outcome, but our ability to identify who is likely to deteriorate after ICU dismissal is limited. The objective of this study is to develop and validate a numerical index, named the Stability and Workload Index for Transfer, to predict ICU readmission. In this prospective cohort study, risk factors for ICU readmission were identified from a broad range of patients&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; admission and discharge characteristics, specific ICU interventions, and in-patient workload measurements. The prediction score was validated in two independent ICUs. One medical and one mixed medical-surgical ICU in two tertiary centers. Consecutive patients requiring &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;24 hrs of ICU care. None. Unplanned ICU readmission or unexpected death following ICU dismissal. In a derivation cohort of 1,131 medical ICU patients, 100 patients had unplanned readmissions, and five died unexpectedly in the hospital following ICU discharge. Predictors of readmission/unexpected death identified in a logistic regression analysis were ICU admission source, ICU length of stay, and day of discharge neurologic (Glasgow Coma Scale) and respiratory (hypoxemia, hypercapnia, or nursing requirements for complex respiratory care) impairment. The Stability and Workload Index for Transfer score predicted readmission more precisely (area under the curve [AUC], 0.75; 95% confidence interval [CI], 0.70-0.80) than the day of discharge Acute Physiology and Chronic Health Evaluation III score (AUC, 0.62; 95% CI, 0.56-0.68). In the two validation cohorts, the Stability and Workload Index for Transfer score predicted readmission similarly in a North American medical ICU (AUC, 0.74; 95% CI, 0.67-0.80) and a European medical-surgical ICU (AUC, 0.70; 95% CI, 0.64-0.76), but was less well calibrated in the medical-surgical ICU. The Stability and Workload Index for Transfer score is derived from information readily available at the time of ICU dismissal and acceptably predicts ICU readmission. It is not known if discharge decisions based on this prediction score will decrease the number of ICU readmissions and/or improve outcome.

Research paper thumbnail of Toward the prevention of acute lung injury: Protocol-guided limitation of large tidal volume ventilation and inappropriate transfusion

Critical Care Medicine, 2007

We evaluated the effect of two quality improvement interventions (low tidal volume ventilation an... more We evaluated the effect of two quality improvement interventions (low tidal volume ventilation and restrictive transfusion) on the development of acute lung injury in mechanically ventilated patients. Observational cohort study. Three intensive care units in a tertiary academic center. We included patients who were mechanically ventilated for &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or =48 hrs excluding those who refused research authorization or had preexisting acute lung injury or pneumonectomy. Multifaceted interdisciplinary intervention consisting of Web-based teaching, respiratory therapy protocol, and decision support within computerized order entry. Of 375 patients who met the inclusion and exclusion criteria, 212 were ventilated before and 163 after the interventions. Baseline characteristics were similar between the two groups except for a lower frequency of sepsis (27% vs. 17%, p = .030), trend toward lower median glucose level (140 mg/dL, interquartile range 118-168 vs. 132 mg/dL, interquartile range 113-156, p = .096), and lower frequency of pneumonia (27% vs. 20%, p = .130) during the second period. We observed a large decrease in tidal volume (10.6-7.7 mL/kg predicted body weight, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001), in peak airway pressure (31-25 cm H2O, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001), and in the percentage of transfused patients (63% to 38%, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001) after the intervention. The frequency of acute lung injury decreased from 28% to 10% (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001). The duration of mechanical ventilation decreased from a median of 5 (interquartile range 4-9) to 4 (interquartile range 4-8) days (p = .030). When adjusted for baseline characteristics in a multivariate logistic regression analysis, protocol intervention was associated with a reduction in the frequency of new acute lung injury (odds ratio 0.21, 95% confidence interval 0.10-0.40). Interdisciplinary intervention effectively decreased large tidal volumes and unnecessary transfusion in mechanically ventilated patients and was associated with a decreased frequency of new acute lung injury.

Research paper thumbnail of Transfusion related acute lung injury in the critically ill: prospective nested case-control study

Rationale: Acute lung injury (ALI) that develops six hours after transfusion (TRALI) is the leadi... more Rationale: Acute lung injury (ALI) that develops six hours after transfusion (TRALI) is the leading cause of transfusion-related mortality. Several transfusion characteristics have been postulated as risk factors for TRALI, but the evidence is limited to retrospective studies.

Research paper thumbnail of Utility of transcranial doppler ultrasonography for confirmatory diagnosis of brain death: two sides of the coin

Transplantation, 2004

Although the clinical examination and documentation of the clinical signs of brain death are very... more Although the clinical examination and documentation of the clinical signs of brain death are very uniform, there are significant differences in the guidelines for using technical confirmatory tests to corroborate the clinical signs. The current study examined the utility of transcranial Doppler ultrasonography (TCD) for confirmation of brain death. After 19 patients were excluded from the study because of lack of bone window or because an apnea test could not be performed because of desaturation, 100 patients (61 patients with clinical brain death, and 39 control patients with Glasgow Coma Score&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;5) were included in the study. The following TCD findings were accepted as confirmatory of brain death when they were found bilaterally or in at least three different arteries for at least 3 minutes within the same examination: (1) brief systolic forward flow or systolic spikes and diastolic reverse flow, (2) brief systolic forward flow or systolic spikes and no diastolic flow, or (3) no demonstrable flow in a patient in whom flow had been clearly documented in a previous TCD examination. The sensitivity and specificity of the first TCD examination for confirmation of brain death were 70.5% and 97.4%, respectively. Eighteen patients with clinical brain death required repeat TCD examinations because of detection of forward systolo-diastolic flow or a diastolic to-and-fro flow pattern, which were not confirmatory for the diagnosis of brain death. Brain death was confirmed ultrasonographically in 12 of 18 patients in a second examination after 12.6 +/- 8.3 hours of clinical brain death, in 2 patients in a third TCD examination, and in 1 patient in a fourth examination. Three clinically brain-dead patients had died before the diagnosis was confirmed by repeat TCD examinations. The sensitivity of TCD reached 100% in our study population after the fourth examination. The sensitivity of TCD is increased with repeat examinations and should be repeated in cases in which systolo-diastolic forward flow is demonstrated after the first TCD. TCD may prolong or shorten the time to declaration of brain death. The necessity of demonstrating cerebral circulatory arrest in patients with clinical brain death is debatable.

Research paper thumbnail of Validation of an electronic surveillance system for acute lung injury

Intensive Care Medicine, 2009

Objective Early detection of acute lung injury (ALI) is essential for timely implementation of ev... more Objective Early detection of acute lung injury (ALI) is essential for timely implementation of evidence-based therapies and enrollment into clinical trials. We aimed to determine the accuracy of computerized syndrome surveillance for detection of ALI in hospitalized patients and compare it with routine clinical assessment. Design Using a near-real time copy of the electronic medical records, we developed and validated a custom ALI electronic alert (ALI “sniffer”) based on the European-American Consensus Conference Definition and compared its performance against provider-derived documentation. Patients and setting A total of 3,795 consecutive critically ill patients admitted to nine multidisciplinary intensive care units (ICUs) of a tertiary care teaching institution were included. Measurements and main results ALI developed in 325 patients and was recognized by bedside clinicians in only 86 (26.5%). Under-recognition of ALI was associated with not implementing protective mechanical ventilation (median tidal volumes of 9.2 vs. 8.0 ml/kg predicted body weight, P < 0.001). ALI “sniffer” demonstrated excellent sensitivity of 96% (95% CI 94–98) and moderate specificity of 89% (95% CI 88–90) with a positive predictive value ranging from 24% (95% CI 13–40) in the heart–lung transplant ICU to 64% (95% CI 55–71) in the medical ICU. Conclusions The computerized surveillance system accurately identifies critically ill patients who develop ALI syndrome. Since the lack of ALI recognition is a barrier to the timely implementation of best practices and enrollment into research studies, computerized syndrome surveillance could be a useful tool to enhance patient safety and clinical research.

Research paper thumbnail of Repeat Percutaneous Tracheostomy in the Neurocritically Ill Patient

Neurocritical Care, 2006

Introduction Percutaneous tracheostomy is a widely used and accepted method for long-term mechani... more Introduction Percutaneous tracheostomy is a widely used and accepted method for long-term mechanical ventilation and airway protection. Neurocritically ill patients sometimes require repeat tracheostomy, which is traditionally considered a relative contraindication for percutaneous procedure. The aim of this study was to determine the safety of repeat percutaneous tracheostomy in neurocritically ill patients with a history of previous tracheostomy. Methods In the 16-bed academic neurointensive care unit, we prospectively enrolled patients who needed new tracheostomy placement for airway protection or prolonged mechanical ventilation and had previously undergone percutaneous tracheostomy placement. We collected data on indications, procedure, periprocedural complications, and outcome of repeated tracheostomy. Results Between January 2001 and October 2005, we enrolled 12 consecutive patients (mean age 35.4±7.0 years) who underwent repeat percutaneous tracheostomy. Head injury was the most common underlying diagnosis (seven patients, 58%). Tracheostomy tube placement was easy and successful in all patients, and none of the patients needed conversion to surgical tracheostomy. In three patients, ultrasound-guided needle aspiration was used before the procedure to confirm the position of the trachea. No patients died or experienced serious complication related to the procedure. Two patients (17%) had a minor periprocedura bleeding, which was controlled with local compression. Long-term outcome was poor, with only two patients alive and off the ventilator at hospital discharge, both with serious disability. Conclusion Repeat percutaneous tracheostomy can be performed safely in neurocritically ill patients who have undergone previous tracheostomy.

Research paper thumbnail of The use of the laryngeal mask airway as an alternative to the endotracheal tube during percutaneous dilatational tracheostomy

Intensive Care Medicine, 2002

Objective: To evaluate the safety and efficiency of the use of the laryngeal mask airway (LMA) du... more Objective: To evaluate the safety and efficiency of the use of the laryngeal mask airway (LMA) during percutaneous dilatational tracheostomy under bronchoscopic guidance comparing with the ventilation via endotracheal tube (ET). Design and setting: Prospective, randomized clinical trial in the eight-bed general intensive care unit of a university hospital. Patients: 60 consecutive adult critically ill patients who required elective tracheostomy for a period of 12 months. Interventions: Patients were randomly assigned to ventilated via LMA (n=30 patients), and to ventilated via ET (n=30). Measurements and results: Blood samples for arterial blood gas analyses were taken before the procedure (first value) and just before the insertion of tracheostomy tube (second value). There was no significant difference in pH, PaO2, or PaCO2 between groups before the procedure. The operating time was significantly shorter in LMA group (4.5±0.8 min versus 5.9±1.4 min). Although the second PaCO2 values were higher than the first in both groups, the rise in was significantly higher in ET group (6.8±3.5 mmHg vs. 4.5±2.4 mmHg). Hypercarbia was noted in 10 patients (38.5%) in the LMA group and 17 (56.7%) in the ET group. The decrease in pH related to hypercarbia was noted in both groups, but it was more significant in the ET group (p<0.05). Conclusion: LMA is an effective and successful ventilatory device during percutaneous dilatational tracheostomy. It improves visualization of the trachea and larynx during fiberoptic-assisted percutaneous dilatational tracheostomy and prevents the difficulties associated with the use of ET such as cuff puncture, tube transection by the needle, and accidental extubation. The use of a bronchoscope and the puncture of the ET cuff cause major increases in PaCO2.

Research paper thumbnail of Device‐Associated Nosocomial Infection Rates in Turkish Medical‐Surgical Intensive Care Units

Infection Control and Hospital Epidemiology, 2006

Background: Routine surveillance of nosocomial infections has become an integral part of infectio... more Background: Routine surveillance of nosocomial infections has become an integral part of infection control and quality assurance in US hospitals. Methods: As part of the International Nosocomial Infection Control Consortium, we performed a prospective nosocomial infection surveillance cohort study in 5 adult intensive care units of 4 Mexican public hospitals using the Centers for Disease Control and Prevention National Nosocomial Infections Surveillance system definitions. Site-specific nosocomial infection rates were calculated. Results: The overall nosocomial infection rate was 24.4% (257/1055) and 39.0 (257/6590) per 1000 patient days. The most common infection was catheter-associated bloodstream infection, 57.98% (149/257), followed by ventilator-associated pneumonia, 20.23% (52/257), and catheter-associated urinary tract infection, 21.79% (56/257). The overall rate of catheter-associated bloodstream infections was 23.1 per 1000 device-days (149/6450); ventilator-associated pneumonia rate was 21.8 per 1000 device-days (52/2390); and catheter-associated urinary tract infection rate was 13.4 per 1000 device-days (56/4184).

Research paper thumbnail of The routine use of pediatric airway exchange catheter after extubation of adult patients who have undergone maxillofacial or major neck surgery: a clinical observational study

Critical Care, 2004

We conducted the present study to determine the usefulness of routinely inserting a pediatric air... more We conducted the present study to determine the usefulness of routinely inserting a pediatric airway exchange catheter (PAEC) before tracheal extubation of adult patients who had undergone maxillofacial or major neck surgery and have risk factors for difficult reintubation. Methods A prospective, observational and clinical study was performed in the 25-bed general intensive care unit of a university hospital. Thirty-six adult patients who underwent maxillofacial or major neck surgery and had risk factors for difficult reintubation were extubated after insertion of the PAEC. Results Four of 36 (11.1%) patients required emergency reintubation after 2, 4, 6 and 18 hours after tracheal extubation, respectively. Reintubation of these patients, which was thought to be nearly impossible by direct laryngoscopy, was easily achieved over the PAEC. Conclusion The PAEC can be a life-saving device during reintubation of patients with risk factors for difficult reintubation such as laryngeo-pharyngeal oedema due to surgical manipulation or airway obstruction resulting from haematoma and anatomic changes. We therefore suggest the routine use of the PAEC in patients undergoing major maxillofacial or major neck surgery.

Research paper thumbnail of Drama