Validation of cardiac output studies from the Mostcare compared to a pulmonary artery catheter in septic patients.

BACKGROUND: The Mostcare monitor is a non-invasive cardiac output monitor. It has been well validated in cardiac surgical patients but there is limited evidence on its use in patients with severe sepsis and septic shock. METHODS: The study included the first 22 consecutive patients with severe sepsis and septic shock in whom the floatation of a pulmonary artery catheter was deemed necessary to guide clinical management. Cardiac output measurements including cardiac output, cardiac index and stroke volume were simultaneously calculated and recorded from a thermodilution pulmonary artery catheter and from the Mostcare monitor respectively. The two methods of measuring cardiac output were compared by Bland-Altman statistics and linear regression analysis. A percentage error of less than 30% was defined as acceptable for this study. RESULTS: Bland-Altman analysis for cardiac output showed a Bias of 0.31 L.min-1, precision (=SD) of 1.97 L.min-1 and a percentage error of 62.54%. For Cardiac Index the bias was 0.21 L.min-1.m-2, precision of 1.10 L.min-1.m-2 and a percentage error of 64%. For stroke volume the bias was 5 mL, precision of 24.46 mL and percentage error of 70.21%. Linear regression produced a correlation coefficient r2 for cardiac output, cardiac index, and stroke volume, of 0.403, 0.306, and 0.3 respectively. CONCLUSION: Compared to thermodilution cardiac output, cardiac output studies obtained from the Mostcare monitor have an unacceptably high error rate. The Mostcare monitor demonstrated to be an unreliable monitoring device to measure cardiac output in patients with severe sepsis and septic shock on an intensive care unit.

The High-Risk Surgical Patient: Current Management Strategies to Reduce Morbidity and Mortality from Organ Dysfunction in Surgical Intensive Care.

A number of patients undergoing major surgery have an associated high morbidity leading to a long stay in the intensive care unit. This group of patients can be regarded as high risk, as their mortality rate is in the region of 20 to 30%. The high-risk patient is likely to have at least one of the characteristics listed in Table 1. Perioperative cardiac morbidity remains the leading cause of postoperative mortality. Although we can now support patients through the early phase of shock, trauma or other life-threatening illness, some will go on to develop progressive failure of one or more vital organs. In this article, we review some of the current processes of care that may improve outcomes in these surgical patients, as improving patient outcome is the purpose of medical care.

The high-risk surgical patient: current management strategies to reduce morbidity and mortality from organ dysfunction in surgical intensive care.

A number of patients undergoing major surgery have an associated high morbidity leading to a long stay in the intensive care unit. This group of patients can be regarded as high risk, as their mortality rate is in the region of 20 to 30%. The high-risk patient is likely to have at least one of the characteristics listed in Table 1. Perioperative cardiac morbidity remains the leading cause of postoperative mortality. Although we can now support patients through the early phase of shock, trauma or other life-threatening illness, some will go on to develop progressive failure of one or more vital organs. In this article, we review some of the current processes of care that may improve outcomes in these surgical patients, as improving patient outcome is the purpose of medical care.

Comparison of intra-articular fentanyl and intra-articular bupivacaine for post-operative pain relief after knee arthroscopy.

A randomized double-blinded study consisting of 107 patients was conducted to compare the effect on post-operative pain relief of intra-articular fentanyl and intra-articular bupivacaine after knee arthroscopy. The results showed that intra-articular bupivacaine produced superior analgesia in the immediate post-operative period. At 2 h post-operatively, the intra-articular bupivacaine group had a mean pain score of 2.0 (standard deviation 2.1, P < 0.05) compared with the intra-articular fentanyl group which had a mean pain score of 3.2 (standard deviation 2.3, P < 0.05). After 2 h post-operatively, intra-articular bupivacaine and intra-articular fentanyl had a similar effect on pain scores. The mean pain score 18 h post-operatively was 2.7 for the intra-articular bupivacaine group (standard deviation 2.2, P value 0.6) compared with the intra-articular fentanyl group which had a mean pain score of 2.8 (standard deviation 1.9, P value 0.6).

Comparison of the structure of human intervertebral discs in the cervical, thoracic and lumbar regions of the spine.

Posterior and anterior heights, cross-sectional area and shape were measured for all the intervertebral discs in four spines from elderly human cadavers. Disc height was a minimum at the T4-5 level; thoracic discs were less wedge-shaped than those in the cervical and lumbar regions. Cross-sectional area increased from the cranial to caudal extremity; at the L5-S1 level the nucleus pulposus occupied a high proportion of this area. Cervical discs tended to have an elliptical cross-sectional shape, thoracic discs were more circular and lumbar discs tended to have an elliptical cross-section which was flattened or re-entrant posteriorly. This shape distribution was quantified by defining a shape index which had a maximum value of 1 for a circular cross-section. Orientations of the reinforcing fibres in the outer lamellae of the anterior annulus fibrosus were measured from 27 discs by X-ray diffraction. For these measurements, C3-4, T7-8 and L2-3 were chosen as representative of cervical, thoracic and lumbar discs. The fibre tilt, with respect to the axis of the spine, was significantly less in the cervical discs (at 65 degrees) than in the thoracic and lumbar discs (about 70 degrees). These findings are interpreted in relation to differing functional requirements and possible mechanisms of failure in the cervical, thoracic and lumbar regions of the spine in the light of current knowledge on the biomechanics of the intervertebral disc.