Sigurbergur Kárason

Warning! Suctioning. A lung model evaluation of closed suctioning systems

Background: Closed system suctioning, CSS, has been advocated to avoid alveolar collapse. However, ventilator manufacturers indicate that extreme negative pressure levels can be obtained during closed system suctioning, impeding the performance of the ventilator.

Direct Measurement of Intratracheal Pressure in Pediatric Respiratory Monitoring

We describe a method based on a Fabry-Perot interferometer at the tip of an optic fiber with a diameter of 0.25 mm for direct measurement of tracheal pressure in pediatric respiratory monitoring. The response time of the pressure transducer and its influence on the resistance of pediatric endotracheal tubes (internal diameter, 2.5 to 5 mm) during constant and dynamic flow at different ventilator settings in a lung model were measured. The transducer was positioned at −1.5 (inside), 0, and +1.5 cm (outside) relative to the tip of the endotracheal tube and compared with a reference pressure inside the trachea. The clinical application of the transducer was tested in five pediatric patients. The response time of the transducer was 1.3 ms. The influence of the fiberoptic transducer on tube resistance was negligible during constant flow in inspiratory and expiratory directions for all endotracheal tubes tested. There was no difference in pressure measurements with the transducer positioned at or 1.5 cm below or above the tip of the endotracheal tube during dynamic measurements. During clinical circumstances insertion of the fiberoptic transducer was easy, recordings were stable, and the safety of the patient was not jeopardized. The fiberoptic transducer provided a reliable and promising way of monitoring tracheal pressure in intubated pediatric patients. The presence of the probe did not interfere with either pressure-flow relationship or patient care and safety. The technique is proposed for monitoring of respiratory mechanics and calculation of changes in tube resistance caused by kinking and secretions.

Evaluation of pressure/volume loops based on intratracheal pressure measurements during dynamic conditions

Background: The aim of this study was to evaluate and compare information about lung mechanics obtained by dynamic pressure/volume loops based on Y‐piece and intratracheal airway pressure.

A new method for non-invasive, manoeuvre-free determination of “static” pressure–volume curves during dynamic/therapeutic mechanical ventilation

Background: Lung mechanics are usually measured using static or quasistatic methods, abandoning normal ventilatory treatment. We have developed a method to calculate the alveolar pressure during dynamic/therapeutic conditions, “the dynostatic pressure” (Pdyn), using airway pressure (P) measured in the trachea and volume (V) and flow (V˙) at the Y‐piece.

Induced hypothermia in comatose survivors of asphyxia: a case series of 14 consecutive cases

Background: Induced hypothermia is widely used for comatose survivors of cardiac arrest. Other causes of hypoxic brain injury carry a poor prognosis when treated using traditional methods. At our hospital, hypothermia has also been used for the management of all comatose survivors of asphyxiation. The aim of the present study was to report the results of the management of these patients.

Severe sepsis and septic shock: a prospective population-based study in Icelandic intensive care units.

Background: The aims of our study were to describe the nationwide epidemiology of sepsis requiring intensive care during an entire year and to evaluate compliance with treatment guidelines.

Ventilator treatment in the Nordic countries. A multicenter survey.

Background: A 1‐day point prevalence study was performed in the Nordic countries to identify ventilator‐treatment strategies in the region.

A practice survey on vasopressor and inotropic drug therapy in Scandinavian intensive care units

Background: This practice survey was performed to analyse the indications for use of vasopressor/inotropic drugs, preferred drugs and doses as well as concomitant monitoring and desired haemodynamic target values in Scandinavian ICUs. An internet‐based reporting system was implemented.

Avoiding bladder catheterisation in total knee arthroplasty: Patient selection criteria and low‐dose spinal anaesthesia

Bladder catheterisation may be inconvenient for patients, delay mobilisation and risk complications. We hypothesised that by excluding pre‐operatively patients at high risk of post‐operative urinary retention, the majority of patients could avoid perioperative catheterisation during low‐dose spinal anaesthesia.

Electrical impedence tomography and heterogeneity of pulmonary perfusion and ventilation in porcine acute lung injury

Background: The heterogeneity of pulmonary ventilation (V), perfusion (Q) and V/Q matching impairs gas exchange in an acute lung injury (ALI). This study investigated the feasibility of electrical impedance tomography (EIT) to assess the V/Q distribution and matching during an endotoxinaemic ALI in pigs.