A. N. Thomas

The prognostic value of serial measurements of serum albumin concentration in patients admitted to an intensive care unit.

The prognostic value of serial measurements of serum albumin concentration during the first 72 h after admission to a general adult intensive care unit was retrospectively reviewed in 348 consecutive critically ill patients over a one year period. The accuracy of the admission APACHE II (Acute Physiology And Chronic Health Evaluation) score in correctly predicting patient outcome was compared with the serum albumin concentration measured at different times after intensive care unit admission. Multiple logistical regression analyses were performed to evaluate whether combining APACHE II and serum albumin into a unified risk index improved prognostic accuracy. Serum albumin concentration on admission was lower in non‐survivors than in survivors and decreased more rapidly in non‐survivors (p < 0.001). The admission serum albumin concentration was found to be an insensitive prognostic indicator. However, serum albumin measured after 24 h was as accurate as the admission APACHE II score in correctly classifying patients according to outcome. There was a good correlation between the admission APACHE II score and serum albumin measured after 24 h but not between the admission APACHE II and the admission serum albumin. Combining the APACHE II score and serial albumin concentrations into a unified risk of death equation did not improve the accuracy of outcome prediction.

Review of patient safety incidents submitted from Critical Care Units in England & Wales to the UK National Patient Safety Agency*

We reviewed and classified all patient safety incidents submitted from critical care units in England and Wales to the National Patient Safety Agency for the first quarter of 2008. A total of 6649 incidents were submitted from 141 organisations (median (range) 23 (1–268 incidents)); 786 were unrelated to the critical care episode and 248 were repeat entries. Of the remaining 5615 incidents, 1726 occurred in neonates or babies, 1298 were associated with temporary harm, 15 with permanent harm and 59 required interventions to maintain life or may have contributed to the patient’s death. The most common main incident groups were medication (1450 incidents), infrastructure and staffing (1289 incidents) and implementation of care (1047 incidents). There were 2789 incidents classified to more than one main group. The incident analysis highlights ways to improve patient safety and to improve the classification of incidents.

Cardiopulmonary resuscitation: a retrospective review

The outcome of patients admitted to intensive care after a cardiac arrest was determined by reviewing intensive care unit records at four hospitals for 1993 and 1994. Of the 112 patients identified, 49 survived intensive care of whom 28 were discharged from hospital. In January 1996, 26 of the 28 patients could be traced; 22 of these were still alive. Seven factors were significantly different between survivors and nonsurvivors. At the cardiac arrest these were the number of direct current shocks (p < 0.05) and adrenaline doses (p < 0.01) given. In intensive care the factors were the presence of reactive pupils (p < 0.01), Glasgow Coma Score (p < 0.001), APACHE II score (p < 0.05), arterial standard bicarbonate (p < 0.05) and the use of inotropes (p < 0.05). It was not possible to use individual variables to predict outcome at the time of intensive care unit admission. The results suggest that neurological function is an important determinant of outcome and more sensitive neurophysiological testing might be a useful prognostic tool.

The use of a blood conservation pressure transducer system in critically ill patients

We tried to determine if a blood conservation pressure transducer system reduced blood transfusions, increased haemoglobin concentration or reduced line infections in critically ill patients. One hundred patients were randomly allocated to conventional or blood conserving systems attached to systemic and pulmonary arterial catheters. Intravascular lines were cultured after removal. There were no significant differences in transfusions or haemoglobin concentration. Blood conservation: median units transfused, 2 (range 0–19); mean haemoglobin at 7 days, 11.2 g.dl−1 (SD, 1.0). Conventional: median units, 2 (range 0–34); mean haemoglobin at 7 days, 11.1 g.dl−1 (SD 1.0). Thirty‐seven of 99 arterial lines were colonised in the controls compared with 29 of 96 in the blood conservation group. Patients who required haemofiltration in both groups had significantly increased transfusion requirements. Haemofiltration: median 6 units (range 0–34) vs. non‐haemofiltered: median 1 (range 0–14; p < 0.001). There were no significant differences in transfusions, haemoglobin concentration or line colonisation with the blood conservation system. There is considerable potential for blood conservation during haemofiltration.

The wrong arterial line flush solution

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Interchangeable oxygen and carbon dioxide in oxygen cylinders

Many longer procedures are now performed using a laryngeal mask airway and artificial ventilation as a first choice for management of the airway. In some cases, such as reconstructive surgery involving free flap techniques, cardiac output monitoring is desirable to optimise graft perfusion. Non-invasive cardiac output monitoring is gaining popularity as a safe and reliable option, with one of the most popular techniques being the use of oesophageal Doppler. The use of this method potentially removes the need for a central line, with its associated risks. With a conventional laryngeal mask airway in place, insertion of an oesophageal Doppler probe is very difficult and may cause problems with the airway seal. During a recent long plastic surgery procedure we placed a ProSeal Laryngeal Mask Airway (Intavent Orthofix, Maidenhead, UK) and then proceeded to use the gastric drainage channel for placement of an oesophageal Doppler probe. After lubrication, the probe was easily placed and functioned well throughout the 8 h procedure. No problems were encountered with airway management, and inflation pressures and tidal volumes remained constant before and after probe placement.

Creatinine and urea clearance during continuous veno‐venous haemofiltration in critically ill patients

Urea and creatinine clearances achieved using continuous veno‐venous haemofiltration were calculated in 16 critically ill patients, during 50 episodes of filtration. The effects of filter life and the volume of ultrafiltrate on these clearances were also evaluated. Clearances were calculated from urea and creatinine concentrations in blood and ultrafiltrate and the volume of ultrafiltrate produced. The overall mean (SD) urea clearance was 26.6 (6.0) ml.min‐1 and the overall creatinine clearance was 30.1 (6.3) ml.min‐1. The mean (SD) ultrafiltrate production was 29.6 (5.9)ml.min‐1. Creatinine clearance was significantly lower in, filters that failed within 24 h (filters < 24h 27.5 (6.3) ml. min 1, filters > 24 h 32.2 (5.5) ml.min‐1). The clerance of both solutes increased with increasing ulfrafiltrate volume (p < 0.001). We conclude that satisfactory clearance of urea and creatinine can be achieved using continuous two‐venous haemofiltration. Increases in ultrafiltrate production lead to similar increases in urea and creatinine clearance. Prolongation of filter life may improve creatinine clearance.