Jukka Räsänen

Moffitt Cancer Center · Program in Anesthesiology

To the Editor:We thank Dr Grimwood for his interest and thoughtful comments on our concept of a ‘smart’ phone based Childhood Pneumonia Screener [1]. The comments are directed in particular to the third phase of the evaluation, an outcome study. Much development and deployment work needs to be conducted before we get to this phase, and the specific...

Acute lung injury (ALI) is known to be associated with the emergence of inspiratory crackles and enhanced transmission of artificial sounds from the airway opening to the chest wall. Recently, we described the effect of ALI on the basic flow-induced breath sounds, separated from the crackles. In this study, we investigated the effects of positive e...

Background: We evaluated an "open lung" ventilation (OV) strategy using low tidal volumes, low respiratory rate, low FiO2, and high continuous positive airway pressure in patients undergoing major lung resections. Materials and methods: In this phase I pilot study, twelve consecutive patients were anesthetized using conventional ventilator setti...

Childhood pneumonia continues to be the number one cause of death in children under five years of age in developing countries. In addition to mortality, pneumonia constitutes an enormous economic and social burden because late diagnosis is associated with high cost of treatment and often leads to chronic health problems. There are several bottlenec...

To evaluate the effect of positive end-expiratory pressure (PEEP) on sound propagation through injured lungs, we injected a multifrequency broad-band sound signal into the airway of eight anesthetized, intubated and mechanically ventilated pigs, while recording transmitted sound at three locations bilaterally on the chest wall. Oleic acid injection...

To evaluate the effect of acute lung injury on the frequency spectra of breath sounds, we made serial acoustic recordings from nondependent, mid-lung and dependent regions of both lungs in ten 35 - 45 kg anesthetized, intubated, and mechanically ventilated pigs during development of acute lung injury induced with intravenous oleic acid in prone or...

To investigate whether geographic differences exist in perioperative opioid administration to children.   To investigate whether perioperative fentanyl use for cleft lip and palate surgery varies between children of three different geographic regions. Differences have been found in perioperative opioid administration to children of differing ethnic...

To investigate the effect of altitude on perioperative opioid requirements in otherwise healthy children. To investigate whether children living and having surgery at high altitude received different doses of fentanyl than those living and having surgery at sea level. Recent studies in animals (Anesthesiology, 105, 2006 and 715) and children with o...

We evaluated the acoustic frequency response of endotracheal tubes (ETs) to assess their effect on respiratory system sound transmission studies. White noise 150-3300 Hz was introduced into 4.0-, 6.0-, and 8.0-mm ETs and recorded at their proximal and distal ends. Four tubes of each size were studied at their original and normalized lengths, in str...

To evaluate the effect of positive end-expiratory pressure on the sound filtering characteristics of injured lungs. Prospective experimental study in the animal laboratory in an academic medical center. Six 35- to 45-kg anesthetized, intubated pigs. Acute lung injury with intravenous oleic acid. We injected a multifrequency broad-band sound signal...

Rapid recovery and weaning from ventilatory support and cardiovascular stability are suggested advantages of isoflurane inhalation, in concentrations ranging from 0.1 to 0.6 vol%, for long-term sedation in mechanical ventilated patients. This study was designed to determine whether isoflurane in low concentrations impairs pulmonary gas exchange by...

To evaluate the utility of monitoring the sound-filtering characteristics of the respiratory system in the assessment of acute lung injury (ALI), we injected a multifrequency broadband sound signal into the airway of five anesthetized, intubated pigs, while recording transmitted sound over the trachea and on the chest wall. Oleic acid injections ef...

Awareness with recall is a rare but serious complication of general anaesthesia with an incidence ranging from 0.1%-0.7%. In the absence of a reliable depth-of-anaesthesia monitor, attempts have been made to predict awareness from intraoperative haemodynamic monitoring data, with little success. Artificial neural networks can sometimes detect relat...

To identify perioperative factors associated with postoperative cardiopulmonary arrest (CA) in the pediatric intensive care unit (PICU) in children undergoing cardiovascular surgery, and to report the outcome of cardiopulmonary resuscitation (CPR) in these patients. We reviewed the medical records of all patients under 16 years of age who had under...

To evaluate the pharmacokinetics of amrinone and its metabolites in neonates and infants after reconstructive surgery for congenital heart disease. Prospective study. Pediatric intensive care unit in a university hospital. Fifteen neonates aged less than 1 month with transposition of the great arteries and 14 infants aged 2 to 6 months with complet...

To report paediatric in-hospital cardiac arrest data according to Utstein style and to determine the effectiveness of cardiopulmonary resuscitation (CPR) in hospitalized children. Design: Retrospective 5-year case series. Urban, tertiary-care children's hospital. All patients who sustained cardiopulmonary arrest. Altogether 227 patients experienced...

The necessity for postoperative inhaled nitric oxide (NO) therapy and predictive factors for that need were retrospectively analysed in 457 paediatric patients at risk of pulmonary hypertensive events following open-heart surgery for congenital heart disease. Inhaled NO was given postoperatively to 46% of the study group and to 23% of all patients...

To compare measured and predicted oxygen consumption (VO2) in children with congenital heart disease. Retrospective study. The cardiac catheterisation laboratory in a university hospital. 125 children undergoing preoperative cardiac catheterisation. VO2 was measured using indirect calorimetry; the predicted values were calculated from regression eq...

To test if analysis of pressure and flow waveform patterns with an artificial intelligence neural network could distinguish between normal and injured lungs. Acute lung injury was induced in ten healthy anesthetized, mechanically ventilated dogs with repeated injections of oleic acid, until arterial blood oxyhemoglobin saturation reached 85% breath...

A study was designed to determine which paediatric trauma patients with no detectable vital signs are likely to benefit from cardiopulmonary resuscitation (CPR). A 10-year retrospective study of all pulseless patients under 16 years of age with trauma in whom CPR was initiated in a prehospital or in-hospital setting in Southern Finland. Forty-one p...

Purpose: We sought to determine whether reduction in dead space and improved V̇A/Q̇ relationships after performing the surgical procedure, bilateral reduction pneumoplasty, could be quantified by Multiple Inert Gas Elimination Technique analySIS (MIGET). Methods: Eight patients, submitted for pneumoplasty, underwent systemic and pulmonary artery an...

To test whether a neural network-based method could differentiate between tracheal and esophageal intubation in anesthetized patients by recognizing breathing circuit pressure and flow waveform patterns. Tracheal tubes were placed in the trachea and in the esophagus of adult patients undergoing elective operations. After ensuring for proper oxygena...

Objective. To test whether a neural network-based method could differentiate between tracheal and esophageal intubation in anesthetized patients by recognizing breathing circuit pressure and flow waveform patterns.Methods. Tracheal tubes were placed in the trachea and in the esophagus of adult patients undergoing elective operations. After ensuring...

The effect of interfacing between spontaneous and mechanical ventilation on ventilation-perfusion (VA/Q) distributions was determined during pressure-support ventilation (PSV) and in the presence and absence of spontaneous breathing during biphasic positive airway pressure (BIPAP) in 10 pigs with methacholine-induced bronchoconstriction. Whereas BI...

Effects of nitric oxide (NO) and aerosolized terbutaline inhalation on ventilation-perfusion (VA/Q) distributions were determined during methacholine-induced bronchoconstriction in nine mechanically ventilated pigs. Animals inhaled, in random order, zero, 20, and 80 parts per million (ppm) of NO or aerosolized terbutaline. Inhalation of either 20 p...

The objective of our study was to evaluate the precision and safety of administering nitric oxide (NO) during full and partial ventilatory support. NO was administered either using a microprocessor-controlled servo ventilator, substituting an NO-N2 mixture for the ventilator's usual air supply or by adding an NO-N2 mixture with a constant flow at t...

The increasing complexity of medicine has emphasized the need to accurately detect, even to anticipate changes in the patient’s condition, and to closely follow the effects of therapy. At the same time, the advancements of technology are enabling us to measure and monitor many physiological variables simultaneously in real time, and in some cases t...

Metabolic responses during recovery from cardiac operations for various congenital heart defects were studied in 30 mechanically ventilated pediatric patients in two groups: infants 1 year or less (group I) and children more than 1 year old (group II). Oxygen consumption (VO2) and carbon dioxide production (VCO2) were measured using a pediatric met...

The present study was designed to evaluate if continuous positive airway pressure (CPAP) augments the effect of nitric oxide (NO) inhalation on matching between ventilation and perfusion (VA/Q) during acute lung injury. Prospective, randomized study. A research laboratory at a university medical center. Ten anesthetized mongrel dogs with oleic acid...

Improved matching between ventilation and perfusion (VA/Q) has been proposed to be a major advantage of partial ventilatory support compared with controlled mechanical ventilation. This study was designed to determine whether a difference in gas exchange exists between partial ventilatory support techniques that allow unsupported spontaneous breath...

Previous investigations have shown that the ventilation-perfusion (VA/Q) mismatch caused by acute lung injury can be alleviated either by inducing vasodilation in ventilated lung units with inhaled nitric oxide (NO) or by inhibiting the synthesis of endogenous NO, which opposes hypoxic pulmonary vasoconstriction. To determine the effects of a combi...

Biphasic positive airway pressure (BIPAP) allows unrestricted spontaneous breathing throughout mechanical ventilation. Effects of spontaneous breathing during BIPAP on pulmonary gas exchange were studied on a randomized basis in 12 dogs with oleic acid-induced lung injury using the multiple inert gas elimination technique. Spontaneous breathing dur...

To evaluate the accuracy with which a patient's aortic blood pressure can be estimated upon separating from cardiopulmonary bypass (CPB), simultaneously recorded radial artery pressure, oscillometric brachial artery pressure, pressure in the CPB circuit, and the surgeon's estimate of blood pressure by aortic palpation were compared to directly meas...

Thirty patients who underwent coronary artery bypass grafting were randomized to receive 30% oxygen by mask either with an ambient airway pressure or with 7.4 mmHg (1 kPa) continuous positive airway pressure (CPAP) for 8 h after extubation. Arterial blood oxygen tension (PaO2) decreased remarkably in the control group after extubation (from 19.2 +/...

To improve the accuracy of early detection of inadvertent esophageal intubation, we designed, trained, and tested a neural network-based computer system to detect the mechanical differences between lung and esophagogastric ventilation. Ten 25 to 30-kg anesthetized swine were sequentially ventilated with tidal volumes of 9, 12, and 15 mL/kg, using t...

We present a case of pulmonary artery perforation in a patient who developed a pneumothorax after cardiac surgery. In the process of inserting a chest tube the patient became tachypnoeic, and developed haemoptysis. The trachea was intubated, and right bronchial intubation was performed with persistent bleeding. The pulmonary artery catheter was gen...

To estimate the changes in the relative amount of ventilatory assistance offered by inspiratory pressure support during changing ventilatory demand with external airway obstruction and with oleic acid-induced acute lung injury. Prospective, controlled, crossover study. Experimental laboratory in a university anesthesiology department. Eight dogs an...

We have measured oxygen consumption and carbon dioxide production by indirect calorimetry in 25 infants and children immediately before and after surgical correction of congenital cardiac malformations. Surgical correction of the cardiac defect caused a decrease in oxygen consumption towards normal. Greatly increased oxygen consumption values were...

To determine whether continuous gas flow in the breathing circuit or an airleak around the tracheal tube cuff will introduce errors into the measurement of oxygen consumption (VO2) with indirect calorimetry. Nonrandomized, controlled trial. Experimental laboratory. Ten healthy, anesthetized mongrel dogs, weighing 8 to 12 kg. Data were recorded at s...

Conclusions: An indirect calorimeter in which measurement of Vo2 is based on internal constant flow rather than spirometry can be used to accurately measure Vo2 from a continuous-flow breathing circuit, if the total circuit flow is less than the internal flow. This limitation may restrict the use of continuous flow to a level below the subject's pe...

To assess the responsiveness of mixed venous oximetry under conditions of supply-independent and supply-dependent oxygen consumption, we subjected ten pigs to graded isovolemic hemodilution while measuring cardiopulmonary variables, including oxygen consumption (VO2), oxygen delivery (DO2), and mixed venous oxyhemoglobin saturation (SvO2). Supply-d...

The effects of withdrawal of ventilatory support on cardiopulmonary function, oxygen consumption and carbon dioxide production were assessed in 25 infants and children within seven days (2.9 +/- 2.5 days; mean +/- SD) of an open heart operation, during weaning from ventilatory support. The average age of the patients was 3.4 +/- 3.5 years and weigh...

Simultaneous superior vena caval (Scvo2) and mixed venous (Svo2) oxyhemoglobin saturation values in 15 children recovering from open heart surgery were compared to assess the value of superior vena caval blood samples in monitoring systemic oxygen supply/demand balance. Samples were obtained immediately following the operation and postoperatively e...

To evaluate the feasibility of airway pressure release ventilation (APRV) in providing ventilatory support to patients with acute lung injury of diverse etiology and mild-to-moderate severity. Prospective, multicenter, nonrandomized crossover trial. ICUs in six major referral hospitals. Fifty adult patients with respiratory failure requiring mechan...

To compare cardiopulmonary function during spontaneous breathing with three continuous-flow breathing circuits. The major difference between these circuits was the degree of flow resistance offered by the exhalation valve. Randomized crossover trial. Twelve infants less than 12 months of age recovering from respiratory failure of variable etiology....

To evaluate the effects of positive airway pressure on lung mechanics and airway pressure transmission into the intrathoracic space, airway and intrathoracic pressure were recorded during stepwise lung inflation in 17 infants undergoing open heart surgery during the first year of life. Eleven of the 17 patients had cuffed tracheal tubes allowing ca...

Traditional mechanical ventilation effects inflation of the lungs by increasing airway pressure above the ambient. Positive pressure lung inflation reverses the physiological variations in airway and intrathoracic pressure that occur during a normal spontaneous respiratory cycle. Such a fundamental alteration in cardiopulmonary mechanics frequently...

With the development of critical care medicine, requirements and techniques of patient monitoring have become increasingly complex. Repeated assessment and rapid adjustment of ongoing therapy requires that variables relevant to the patient’s disease process be monitored continuously in an on-line fashion. Until recently, monitoring of pulmonary fun...

The effects of ventilation with 30% and 100% oxygen were investigated on the circulatory and electrocardiographic response to electroconvul-sive therapy (ECT) in 12 patients during 40 treatments. Administration of 30% oxygen resulted in a 25% decrease in seizure duration compared with 100% oxygen (P < 0.0125). Hypoxaemia, defined as SaO2 less than...

After operative coronary revascularization, 14 consenting adults received conventional positive pressure ventilation (PPV). When they were hemodynamically stable, data were collected during PPV and then during airway pressure release ventilation (APRV). During APRV, airway pressure (Paw) was reduced periodically at the lowest frequency which produc...

To evaluate the efficacy of our routine method of cardiopulmonary monitoring of accurate management of respiratory therapy, continuous positive airway pressure (CPAP) was titrated in 11 surgical intensive care patients within +/- 7.5 cm H2O of the clinically selected level. Cardiopulmonary data were independently and retrospectively reviewed by thr...

The hemodynamic sequelae of conventional positive pressure ventilation (CPPV), airway pressure release ventilation (APRV), and spontaneous breathing were compared with continuous positive airway pressure (CPAP) in ten anesthetized dogs who had ventilatory failure with and without parenchymal lung injury. The APRV corrected respiratory acidosis with...

Computed tomography (CT) of the chest offers improved resolution and sensitivity for evaluating chest pathologic conditions compared with other imaging techniques. Intensive care unit patients with portable chest findings that diverge from the clinical course may actually have severe intrathoracic disease that can be detected with CT. Our three pat...

Bronchial drainage, positive-pressure lung inflation, chest-wall percussion, and suctioning were performed in a patient with postoperative atelectasis, lung infection, and respiratory failure. A previously undiagnosed posterior lung abscess subsequently drained into the bronchial tree, causing dissemination of the infection and a severe deteriorati...

We designed a ventilation-perfusion index (VQI) to estimate venous admixture (Qsp/Qt) in a real-time fashion by simultaneous pulse and pulmonary artery oximetry in 17 patients with acute respiratory failure. Changes in Qsp/Qt were produced by altering the level of continuous positive airway pressure. VQI correlated well with Qsp/Qt (r = 0.78). This...

The utility of integrated pulse and pulmonary artery oximetry, known as dual oximetry, was evaluated by monitoring 10 critically ill surgical patients for a total of 208 patient hours. The ventilation-perfusion index (VQI), an estimate of venous admixture, and the oxygen extraction index (O2EI), an estimate of tissue oxygen utilization coefficient,...

Pulmonary edema secondary to acute left ventricular failure is a medical emergency in which effective measures to stablilize cardiorespiratory function are critically important to assure the best possible outcome. Pulmonary edema increases the work of breathing and effects arterial hypoxemia which may rapidly alter cardiac performance in an unfavor...

As critical care medicine has developed, patient monitoring capability has become increasingly complex. Variables relevant to the patient’s disease process preferably should be monitored continuously in an on-line fashion, to allow repeated assessment and rapid adjustments of ongoing therapy. Monitoring should not subject the patient to a significa...

We studied the theoretical basis for continuous monitoring of pulmonary gas exchange using arterial and mixed venous oximetry by examining the mathematical relationships between the calculated venous admixture (Qsp/Qt) and the ventilation-perfusion index, which is derived from oxyhemoglobin saturations. We compared this relationship with that betwe...

Total body oxygen utilization coefficient was estimated using continuous pulse and pulmonary artery oximetry (dual oximetry) in 17 patients with respiratory failure. Change in arterial and mixed venous oxygen saturations was induced by altering airway pressure. Continuous measurement of mixed venous oxygen saturation provided an accurate and linear...

The clinical utility of combined pulse and pulmonary artery oximetry (dual oximetry) in titrating continuous positive airway pressure (CPAP) therapy was tested in 17 patients with acute respiratory failure. The level of CPAP was altered in 2.5 cmH2O increments and decrements, while conventional measurements of cardiopulmonary function and continuou...

The efficacy of continuous positive airway pressure (CPAP) administered with a face mask was compared to oxygen supplementation in 40 patients with acute cardiogenic pulmonary edema. Baseline arterial blood gas values and pH, heart rate, respiratory rate, and blood pressure were recorded after patients breathed 28 percent oxygen with an ambient air...

The cardiopulmonary effects of conventional controlled mechanical ventilation (CMV), high frequency controlled mechanical ventilation (HFV), and intermittent mandatory ventilation (IMV) were compared in nine patients with ischemic left ventricular dysfunction and pulmonary edema. Ventilatory support during IMV and CMV was adjusted by changing the v...

A considerable disparity presently exists between the marketing of new modalities of positive pressure ventilation and the scientific evaluation of their utility in patient care. A ventilator that would include only features proven effective clinically would likely be considerably lighter in weight, smaller in size, and cheaper in price than most c...

Need for respiratory support in patients with heart failure is usually related to the cardiac disease and develops with sudden left ventricular (LV) decompensation. The triggering event may be coronary spasm or thrombosis that impairs myocardial oxygen delivery, or increase in cardiac work unmatched by the coronary circulation. Even a transient isc...

“Assessment” of oxygenation may entail measurement and calculation of a variety of physiologic variables. However, the oxygen tension of arterial blood (PaO2) is by far the most common measurement utilized in the determination of “adequacy” of oxygenation. Because of ease of measurement, PaO2 often is used as a guide to oxyen therapy, ventilator ad...

Patients suffering from acute lung injury (ALI) require intensive therapy which usually includes vigorous mechanical ventilatory support, often with elevated expiratory airway pressure. Originally, mechanical ventilatory support was applied to patients who had relatively normal lung function, but a neuromuscular inability to breathe adequately. The...

Acute hemodynamic effects of a routine pericardial closure after cardiopulmonary bypass was studied in 29 patients undergoing cardiac surgery. Clinically, the pericardial closure was well tolerated. Pericardial closure resulted in an 8% decrease of cardiac output (p less than 0.01) while cardiac index remained normal (2.9 l/min/m2 +/- 0.6 SD). The...

This paper discusses the respiratory therapy in patients with acute respiratory failure due to acute myocardial infarction (AMI). Several events in the course of AMI may lead to respiratory failure requiring ventilatory support. Since the lungs and the heart form a functional unit, therapy directed at one frequently affects the other. Particularly...

The therapeutic efficacy of continuous positive airway pressure (CPAP) administered by face mask was studied in 40 patients with acute cardiogenic pulmonary edema and respiratory failure. Arterial blood gas values and pH, systemic arterial pressure, heart rate and respiratory rate were measured during administration of 30% oxygen with a high-flow f...

The cardiopulmonary effects of continuous positive airway pressure (CPAP) were studied in 14 patients with acute myocardial infarction complicated by circulatory and respiratory failure. Cardiac performance, lung mechanics, and gas exchange were assessed during 50 percent mechanical ventilatory support at end-expiratory airway pressure levels of 0,...

The cardiopulmonary effects of ventilatory support were studied in 12 patients with an acute myocardial infarction complicated by respiratory failure. At constant end-expiratory pressure, controlled mechanical ventilation, intermittent mandatory ventilation with 50 percent mechanical support, and spontaneous breathing all resulted in acceptable blo...