Does preoperative multidisciplinary team assessment of high-risk patients improve the safety and outcomes of patients undergoing surgery?

BACKGROUND

International guidelines recommend preoperative multidisciplinary team (MDT) assessment for high-risk surgical patients. Preoperative MDT meetings can help to improve surgical care, but there is little evidence on whether they improve patient outcomes.

METHODS

This paper aims to share our experience of MDT meetings for high-risk surgical patients to underline their added value to the current standard of care. An observational study of a retrospective cohort of preoperative high-risk MDT meetings of a tertiary referral hospital between January 2015 and December 2020. For 249 patients the outcomes preoperative data, MDT decisions, and patient outcomes were collected from electronic health records.

MAIN RESULTS

A total of 249 patients were discussed at high-risk MDT meetings. Most of the patients (97%) were assessed as having an American Society of Anesthesiology score ≥ 3, and 219 (88%) had a European Society of Cardiology and European Society of Anaesthesiology risk score of intermediate or high. After MDT assessment, 154 (62%) were directly approved for surgery, and 39 (16%) were considered ineligible for surgery. The remaining 56 (23%) patients underwent additional assessments before reconsideration at a high-risk MDT meeting. The main reason for patients being discussed at the high-risk MDT meeting was to assess the risk-benefit ratio of surgery. Ultimately, 184 (74%) patients underwent surgery. Of the operated patients, 122 (66%) did not have a major complication in the postoperative period, and 149 patients (81%) were alive after one year.

CONCLUSIONS

This cohort study shows the vulnerability and complexity of high-risk patients but also shows that the use of an MDT assessment contributes too improved peri- and postoperative treatment strategies in high-risk patients. Most patients underwent surgery after careful risk assessment and, if deemed necessary, preoperative and perioperative treatment optimization to reduce their risk.

Prehospital accuracy of (H)EMS pelvic ring injury assessment and the application of non-invasive pelvic binder devices

BACKGROUND

Pre-hospital application of a non-invasive pelvic binder device (NIPBD) is essential to increase chances of survival by limiting blood loss in patients with an unstable pelvic ring injury. However, unstable pelvic ring injuries are often not recognized during prehospital assessment. We investigated the prehospital (helicopter) emergency medical services ((H)EMS)' accuracy of the assessment of unstable pelvic ring injuries and NIPBD application rate.

METHODS

We performed a retrospective cohort study on all patients with a pelvic injury transported by (H)EMS to our level one trauma centre between 2012 and 2020. Pelvic ring injuries were included and radiographically categorized using the Young & Burgess classification system. Lateral Compression (LC) type II/III -, Anterior-Posterior (AP) type II/III - and Vertical Shear (VS) injuries were considered as unstable pelvic ring injuries. (H)EMS charts and in-hospital patient records were evaluated to determine the sensitivity, specificity and diagnostic accuracy of the prehospital assessment of unstable pelvic ring injuries and prehospital NIPBD application.

RESULTS

A total of 634 patients with pelvic injuries were identified, of whom 392 (61.8%) had pelvic ring injuries and 143 (22.6%) had unstable pelvic ring injuries. (H)EMS personnel suspected a pelvic injury in 30.6% of the pelvic ring injuries and in 46.9% of the unstable pelvic ring injuries. An NIPBD was applied in 108 (27.6%) of the patients with a pelvic ring injury and in 63 (44.1%) of the patients with an unstable pelvic ring injury. (H)EMS prehospital diagnostic accuracy measured in pelvic ring injuries alone was 67.1% for identifying unstable pelvic ring injuries from stable pelvic ring injuries and 68.1% for NIPBD application.

CONCLUSION

The (H)EMS prehospital sensitivity of unstable pelvic ring injury assessment and NIPBD application rate is low. (H)EMS did not suspect an unstable pelvic injury nor applied an NIPBD in roughly half of all unstable pelvic ring injuries. We advise future research on decision tools to aid the routine use of an NIPBD in any patient with a relevant mechanism of injury.

Third generation continuous flow left ventricular assist devices; a comparative outcome analysis by device type

Background

Continuous-flow left ventricular assist devices (CF-LVADs) have become a standard of care in end-stage heart failure (HF). Device-related complications remain high. Limited data exists comparing outcomes of the HeartMate 3 (HM3) and the HeartWare HVAD (HW). We aimed to analyze HM3 and HW devices implanted over the past 10 years with a focus on long-term clinical outcomes of respective patients.

Methods

Investigator-initiated comparative, retrospective observational analysis of all patients who underwent primary implantation of a centrifugal CF-LVAD at our tertiary care academic center between January 2010 and December 2020. Data derived from a prospective registry, and included all patients receiving a HM3 or HW device. Primary endpoint was overall (all-cause) mortality and heart transplantation. Secondary endpoints included device-related major adverse cardiac and cerebrovascular events (MACCE), as well right heart failure (RHF), gastrointestinal (GI) bleeding, driveline infections, and surgical re-interventions.

Results

Out of 106 primary CF-LVAD implantations, 36 (34%) received HM3 and 70 (66%) received HW. Median follow-up time was 1.48 years [interquartile range 0.67, 2.41] and did not differ between devices (p=0.739). HM3 was more often implanted in men (91.7% vs. 72.9%, p=0.024), patients were older (median 61 years [54, 66.5] vs. 52.5 years [43, 60], p<0.001), had a higher body mass index (BMI) (median 26.7 kg/m2 [23.4, 29.0] vs. 24.3 kg/m2 [20.7, 27.4], p=0.013), had more comorbidities and were more likely targeted for destination therapy (DT) (36.1% vs. 14.3%, p=0.010). Death occurred in 33.3% of HM3 patients, compared to 22.9% of HW patients, p=0.247 (probability of survival at 2 years 54.7% vs. 74.1%, p=0.296). After adjustment for confounders, we observed a significant 6-fold risk increase in device malfunctions for HW (hazard ratio (HR) 6.49, 95% CI [1.89, 22.32], p=0.003), but no significant differences between devices in pump thrombosis (p=0.173) or overall survival (p=0.801).

Conclusions

Comparing long-term outcomes between HeartMate 3 and HeartWare HVAD for LVAD support from a prospective registry, HeartWare HVAD patients had a significantly higher risk of device malfunctions. No significant differences were evident between devices in overall survival, and in respect to most clinical outcomes.

Funding Acknowledgement

Type of funding sources: None. KM Plot primary and secondary outcomesRisk analysis on all outcomes

Prehospital time and mortality in polytrauma patients: a retrospective analysis

Background

The time from injury to treatment is considered as one of the major determinants for patient outcome after trauma. Previous studies already attempted to investigate the correlation between prehospital time and trauma patient outcome. However, the outcome for severely injured patients is not clear yet, as little data is available from prehospital systems with both Emergency Medical Services (EMS) and physician staffed Helicopter Emergency Medical Services (HEMS). Therefore, the aim was to investigate the association between prehospital time and mortality in polytrauma patients in a Dutch level I trauma center.

Methods

A retrospective study was performed using data derived from the Dutch trauma registry of the National Network for Acute Care from Amsterdam UMC location VUmc over a 2-year period. Severely injured polytrauma patients (Injury Severity Score (ISS) ≥ 16), who were treated on-scene by EMS or both EMS and HEMS and transported to our level I trauma center, were included. Patient characteristics, prehospital time, comorbidity, mechanism of injury, type of injury, HEMS assistance, prehospital Glasgow Coma Score and ISS were analyzed using logistic regression analysis. The outcome measure was in-hospital mortality.

Results

In total, 342 polytrauma patients were included in the analysis. The total mortality rate was 25.7% (n = 88). Similar mean prehospital times were found between the surviving and non-surviving patient groups, 45.3 min (SD 14.4) and 44.9 min (SD 13.2) respectively (p = 0.819). The confounder-adjusted analysis revealed no significant association between prehospital time and mortality (p = 0.156).

Conclusion

This analysis found no association between prehospital time and mortality in polytrauma patients. Future research is recommended to explore factors of influence on prehospital time and mortality.

Characteristics of helicopter emergency medical services (HEMS) dispatch cancellations during a six-year period in a Dutch HEMS region

Background

For decades, Helicopter Emergency Medical Services (HEMS) contribute greatly to prehospital patient care by performing advanced medical interventions on-scene. Unnecessary dispatches, resulting in cancellations, cause these vital resources to be temporarily unavailable and generate additional costs. A previous study showed a cancellation rate of 43.5% in our trauma region. However, little recent data about cancellation rates and reasons exist, despite revision of dispatch protocols. This study examines the current cancellation rate in our trauma region over a six-year period. Additionally, cancellation reasons are evaluated per type of dispatch and initial incident report, upon which HEMS is dispatched.

Methods

This retrospective study analyzed the data of the Dutch HEMS Lifeliner 1 (North-West region of the Netherlands, covering a population of 5 million inhabitants), analyzing all subsequent cases between April 1st 2013 and April 1st 2019. Patient characteristics, type of dispatch (primary; based on dispatcher criteria versus secondary, as judged by the first ambulance team on site), initial incident report received by the EMS dispatch center, and information regarding day- or nighttime dispatches were collected. In case of cancellation, cancel rate and reason per type of dispatch and initial incident report were assessed.

Results

In total, 18,638 dispatches were included. HEMS was canceled in 54.5% (95% CI 53.8–55.3%) of cases. The majority of canceled dispatches (76.1%) were canceled because respiratory, hemodynamic, and neurologic parameters were stable. Dispatches simultaneously activated with EMS (primary dispatch) were canceled in 58.3%, compared to 15.1% when HEMS assistance was requested by EMS based on their findings on-scene (secondary dispatch). A cancellation rate of 54.6% was found in trauma related dispatches (n = 12,148), compared to 52.2% in non-trauma related dispatches (n = 5378). Higher cancellation rates exceeding 60% were observed in the less common dispatch categories, e.g., anaphylaxis (66.3%), unknown incident report (66.0%), assault with a blunt object (64.1%), obstetrics (62.8%), and submersion (61.9%).

Conclusion

HEMS cancellations are increased, compared to previous research in our region. Yet, the cancellations are acceptable as the effect on HEMS’ unavailbility remains minimized. Focus should be on identifying the patient in need of HEMS care while maintaining overtriage rates low. Continuous evaluation of HEMS triage is important, and dispatch criteria should be adjusted if necessary.

Prehospital fluid administration in patients with severe traumatic brain injury: A systematic review and meta-analysis

BACKGROUND

Prehospital management of severe traumatic brain injury (TBI) focuses on preventing secondary brain injury. Therefore, hypotension should be prevented, or if present, should be promptly treated in order to maintain optimal cerebral perfusion pressure. Fluid resuscitation is a traditional mainstay in the prehospital treatment of hypotension, however, the choice of fluid type that is to be administered in the prehospital setting is the subject of an on-going debate. This systematic review and meta-analysis was therefore performed to assess the effect of different fluid types on outcome in patients with severe TBI.

METHODS

PubMed, Embase and Web of Science were searched for articles up to March 2020. Studies comparing two or more prehospital administered fluid types with suspected or confirmed severe TBI were deemed eligible for inclusion. Studied outcomes were mortality and (extended) Glasgow Outcome Scale (GOS). The meta-analysis tested for differences in survival between hypertonic saline (HTS) and normotonic crystalloids (i.e. normal saline or Lactated Ringer's) and between hypertonic saline with dextran (HSD) and normotonic crystalloids. The systematic review is registered in the PROSPERO register with number CRD42020140423.

RESULTS

This literature search yielded a total of 519 articles, of which 12 were included in the systematic review and 6 were included in the meta-analysis. Eleven studies found no statistically significant difference in survival between patients treated with different fluid types (e.g. normal saline and hypertonic saline). All studies assessing neurological outcome, measured through (extended) GOS, found no statistically significant difference between different fluid types. Meta-analysis showed no better survival for patients treated with HSD, when compared to normotonic crystalloids (overall RR 0.99, 95% CI 0.93-1.06). Moreover, HTS compared to normotonic crystalloids does not result in a better survival (overall RR 1.04, 95% CI 0.97-1.12).

CONCLUSIONS

This systematic review and meta-analysis did not demonstrate a survival or neurological benefit for one specific fluid type administered in the prehospital setting.

Routine lung ultrasound to detect postoperative pulmonary complications following major abdominal surgery: a prospective observational feasibility study

Background

Postoperative pulmonary complications after major abdominal surgery are associated with adverse outcome. The diagnostic accuracy of chest X-rays (CXR) to detect pulmonary disorders is limited. Alternatively, lung ultrasound (LUS) is an established evidence-based point-of-care diagnostic modality which outperforms CXR in critical care. However, its feasibility and diagnostic ability for postoperative pulmonary complications following abdominal surgery are unknown. In this prospective observational feasibility study, we included consecutive patients undergoing major abdominal surgery with an intermediate or high risk developing postoperative pulmonary complications according to the Assess Respiratory risk In Surgical patients in CATalonia (ARISCAT) score. LUS was routinely performed on postoperative days 0–3 by a researcher blinded for CXR or other clinical findings. Then, reports were drawn up for LUS concerning feasibility and detection rates of postoperative pulmonary complications. CXRs were performed on demand according to daily clinical practice. Subsequently, we compared LUS and CXR findings.

Results

A total of 98 consecutive patients with an ARISCAT score of 41 (34–49) were included in the study. LUS was feasible in all patients. In 94 (95%) patients, LUS detected one or more postoperative pulmonary complications during the first four postoperative days. On day 0, LUS detected 31 out of 43 patients (72.1%) with one or more postoperative pulmonary complications, compared to 13 out of 36 patients (36.1%) with 1 or more postoperative pulmonary complications detected with CXR RR 2.0 (95 CI [1.24–3.20]) (p = 0.004). The number of discordant observations between both modalities was high for atelectasis 23 (43%) and pleural effusion 29 (54%), but not for pneumothorax, respiratory infection and pulmonary edema 8 (15%), 3 (5%), and 5 (9%), respectively.

Conclusions

This study shows that LUS is highly feasible and frequently detects postoperative pulmonary complications after major abdominal surgery. Discordant observations in atelectasis and pleural effusions for LUS and CXR can be explained by a superior diagnostic ability of LUS in detecting these conditions. The effects of LUS as primary imaging modality on patient outcome should be evaluated in future studies.

Lung ultrasound compared with chest X-ray in diagnosing postoperative pulmonary complications following cardiothoracic surgery: a prospective observational study

Postoperative pulmonary complications are common after cardiothoracic surgery and are associated with adverse outcomes. The ability to detect postoperative pulmonary complications using chest X-rays is limited, and this technique requires radiation exposure. Little is known about the diagnostic accuracy of lung ultrasound for the detection of postoperative pulmonary complications after cardiothoracic surgery, and we therefore aimed to compare lung ultrasound with chest X-ray to detect postoperative pulmonary complications in this group of patients. We performed this prospective, observational, single-centre study in a tertiary intensive care unit treating adult patients who had undergone cardiothoracic surgery. We recorded chest X-ray findings upon admission and on postoperative days 2 and 3, as well as rates of postoperative pulmonary complications and clinically-relevant postoperative pulmonary complications that required therapy according to the treating physician as part of their standard clinical practice. Lung ultrasound was performed by an independent researcher at the time of chest X-ray. We compared lung ultrasound with chest X-ray for the detection of postoperative pulmonary complications and clinically-relevant postoperative pulmonary complications. We also assessed inter-observer agreement for lung ultrasound, and the time to perform both imaging techniques. Subgroup analyses were performed to compare the time to detection of clinically-relevant postoperative pulmonary complications by both modalities. We recruited a total of 177 patients in whom both lung ultrasound and chest X-ray imaging were performed. Lung ultrasound identified 159 (90%) postoperative pulmonary complications on the day of admission compared with 107 (61%) identified with chest X-ray (p < 0.001). Lung ultrasound identified 11 out of 17 patients (65%) and chest X-ray 7 out of 17 patients (41%) with clinically-relevant postoperative pulmonary complications (p < 0.001). The clinically-relevant postoperative pulmonary complications were detected earlier using lung ultrasound compared with chest X-ray (p = 0.024). Overall inter-observer agreement for lung ultrasound was excellent (κ = 0.907, p < 0.001). Following cardiothoracic surgery, lung ultrasound detected more postoperative pulmonary complications and clinically-relevant postoperative pulmonary complications than chest X-ray, and at an earlier time-point. Our results suggest lung ultrasound may be used as the primary imaging technique to search for postoperative pulmonary complications after cardiothoracic surgery, and will enhance bedside decision making.

Lactate clearance metrics are not superior to initial lactate in predicting mortality in trauma

PURPOSE

Despite the availability of different lactate clearance (LC) metrics for clinical use, it remains unknown which metric is superior as a clinical predictor for outcome, particularly in trauma patients. This retrospective study compared four previously described metrics of LC and examined the association between LC and outcome in trauma patients.

METHODS

Lactate values of trauma patients admitted to a level I trauma center between 2010 and 2013 were retrieved from patient records. LC was calculated according to Huckabee, Regnier et al., Billeter et al. and Zhang et al. Patients were categorized as isolated traumatic brain injury (TBI), trauma with TBI, and trauma without TBI. The primary study outcome was in-hospital mortality.

RESULTS

367 trauma patients were eligible for LC calculation. Only LC by Zhang et al. [area under the curve (AUC) > 0.622, p < 0.01], and Billeter et al. (AUC > 0.616, p < 0.05) were predictive for mortality in trauma patients with and without TBI. However, both were equally prognostic as the initial lactate value for in-hospital mortality. The prognostic value of initial lactate and lactate clearance for in-hospital mortality were not found to differ between isolated TBI, polytrauma with TBI, and trauma without TBI.

CONCLUSIONS

LC metrics based on the methods of Zhang et al. and Billeter et al. predicted mortality in trauma patients, and their prognostic value did not differ between patients with and without TBI. However, initial lactate value was equally prognostic as these LC metrics. Our findings suggest that a single initial lactate measurement may be a more clinically useful tool to predict mortality than the calculation of lactate clearance.

Quantitative agreement between [(15)O]H2O PET and model free QUASAR MRI-derived cerebral blood flow and arterial blood volume

The purpose of this study was to assess whether there was an agreement between quantitative cerebral blood flow (CBF) and arterial cerebral blood volume (CBVA) measurements by [(15)O]H2O positron emission tomography (PET) and model-free QUASAR MRI. Twelve healthy subjects were scanned within a week in separate MRI and PET imaging sessions, after which quantitative and qualitative agreement between both modalities was assessed for gray matter, white matter and whole brain region of interests (ROI). The correlation between CBF measurements obtained with both modalities was moderate to high (r(2): 0.28-0.60, P < 0.05), although QUASAR significantly underestimated CBF by 30% (P < 0.001). CBVA was moderately correlated (r(2): 0.28-0.43, P < 0.05), with QUASAR yielding values that were only 27% of the [(15)O]H2O-derived values (P < 0.001). Group-wise voxel statistics identified minor areas with significant contrast differences between [(15)O]H2O PET and QUASAR MRI, indicating similar qualitative CBVA and CBF information by both modalities. In conclusion, the results of this study demonstrate that QUASAR MRI and [(15)O]H2O PET provide similar CBF and CBVA information, but with systematic quantitative discrepancies.

Application of current guidelines for chest compression depth on different surfaces and using feedback devices: a randomized cross-over study

BACKGROUND

Current cardiopulmonary resuscitation (CPR)-guidelines recommend an increased chest compression depth and rate compared to previous guidelines, and the use of automatic feedback devices is encouraged. However, it is unclear whether this compression depth can be maintained at an increased frequency. Moreover, the underlying surface may influence accuracy of feedback devices. We investigated compression depths over time and evaluated the accuracy of a feedback device on different surfaces.

METHODS

Twenty-four volunteers performed four two-minute blocks of CPR targeting at current guideline recommendations on different surfaces (floor, mattress, 2 backboards) on a patient simulator. Participants rested for 2 minutes between blocks. Influences of time and different surfaces on chest compression depth (ANOVA, mean [95% CI]) and accuracy of a feedback device to determine compression depth (Bland-Altman) were assessed.

RESULTS

Mean compression depth did not reach recommended depth and decreased over time during all blocks (first block: from 42 mm [39-46 mm] to 39 mm [37-42 mm]). A two-minute resting period was insufficient to restore compression depth to baseline. No differences in compression depth were observed on different surfaces. The feedback device slightly underestimated compression depth on the floor (bias -3.9 mm), but markedly overestimated on the mattress (bias +12.6 mm). This overestimation was eliminated after correcting compression depth by a second sensor between manikin and mattress.

CONCLUSION

Strategies are needed to improve chest compression depth, and more than two providers should alternate with chest compressions. The underlying surface does not necessarily adversely affect CPR performance but influences accuracy of feedback devices. Accuracy is improved by a second, posterior, sensor.

Accuracy and precision of pseudo-continuous arterial spin labeling perfusion during baseline and hypercapnia: a head-to-head comparison with ¹⁵O H₂O positron emission tomography

Measurements of the cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) provide useful information about cerebrovascular condition and regional metabolism. Pseudo-continuous arterial spin labeling (pCASL) is a promising non-invasive MRI technique to quantitatively measure the CBF, whereas additional hypercapnic pCASL measurements are currently showing great promise to quantitatively assess the CVR. However, the introduction of pCASL at a larger scale awaits further evaluation of the exact accuracy and precision compared to the gold standard. (15)O H₂O positron emission tomography (PET) is currently regarded as the most accurate and precise method to quantitatively measure both CBF and CVR, though it is one of the more invasive methods as well. In this study we therefore assessed the accuracy and precision of quantitative pCASL-based CBF and CVR measurements by performing a head-to-head comparison with (15)O H₂O PET, based on quantitative CBF measurements during baseline and hypercapnia. We demonstrate that pCASL CBF imaging is accurate during both baseline and hypercapnia with respect to (15)O H₂O PET with a comparable precision. These results pave the way for quantitative usage of pCASL MRI in both clinical and research settings.

Monitoring tissue oxygenation by near infrared spectroscopy (NIRS): background and current applications

Conventional cardiovascular monitoring may not detect tissue hypoxia, and conventional cardiovascular support aiming at global hemodynamics may not restore tissue oxygenation. NIRS offers non-invasive online monitoring of tissue oxygenation in a wide range of clinical scenarios. NIRS monitoring is commonly used to measure cerebral oxygenation (rSO(2)), e.g. during cardiac surgery. In this review, we will show that tissue hypoxia occurs frequently in the perioperative setting, particularly in cardiac surgery. Therefore, measuring and obtaining adequate tissue oxygenation may prevent (postoperative) complications and may thus be cost-effective. NIRS monitoring may also be used to detect tissue hypoxia in (prehospital) emergency settings, where it has prognostic significance and enables monitoring of therapeutic interventions, particularly in patients with trauma. However, optimal therapeutic agents and strategies for augmenting tissue oxygenation have yet to be determined.

The differential effects of recombinant brain natriuretic peptide, nitroglycerine and dihydralazine on systemic oxygen delivery and gastric mucosal microvascular oxygenation in dogs

Brain natriuretic peptide has vasodilatory properties and may thus increase splanchnic perfusion and oxygenation. We compared the effects of recombinant brain natriuretic peptide on gastric mucosal microvascular haemoglobin oxygenation (reflectance spectrophotometry) and systemic variables with those of equi-hypotensive doses of two other vasodilators (nitroglycerine and dihydralazine). Chronically instrumented, healthy dogs were randomly allocated to receive on different days, one of the three drugs (nitroglycerine and dihydralazine doses titrated to reduce mean arterial pressure by ∼20%). Brain natriuretic peptide significantly increased gastric mucosal microvascular haemoglobin oxygenation selectively, i.e. without concomitant haemodynamic effects. In contrast, the other vasodilators either did not increase gastric mucosal microvascular haemoglobin oxygenation at all (nitroglycerine), or did so only with marked increases in other systemic haemodynamic variables (dihydralazine). Our data suggest a potential role of recombinant brain natriuretic peptide selectively for increasing microvascular mucosal oxygenation. Studies are required to extend these findings to the clinical setting.

Paresis of cranial nerve VI (N. abducens) after thoracic dural perforation

Epidural anesthesia is associated with the risk of unintended dural perforation and concomitant leakage of cerebrospinal fluid (CSF) from the subarachnoidal space. This may remain asymptomatic or trigger post-dural puncture headache (PDPH). Cerebral nerve lesions after attempted epidural anesthesia are very rare. Here we report a case of unilateral paresis of the cranial nerve VI (N. abducens) after attempted thoracic epidural anesthesia. Herein, diagnosis of N. abducens paresis was probably delayed because the optical symptoms, such as blurred and double vision, were attributed to optical hallucinations caused by a concomitant (S)-ketamine infusion. In all patients with optical symptoms such as blurred or double vision a paresis of the abducens nerve should be considered.

Cormack-Lehane classification revisited

BACKGROUND

The Cormack-Lehane (CL) classification is broadly used to describe laryngeal view during direct laryngoscopy. This classification, however, has been validated by only a few studies reporting inconclusive data concerning its reliability. This discrepancy between widespread use and limited evidence prompted us to investigate the knowledge about the classification among anaesthesiologists and its intra- and inter-observer reliability.

METHODS

One hundred and twenty interviews were performed at a major European anaesthesia congress. Participants were interviewed about their general knowledge on grading systems to classify laryngeal view during laryngoscopy and were subsequently asked to define the grades of the CL classification. Inter- and intra-observer reliabilities were tested in 20 anaesthesiologists well familiar with the CL classification, who performed 100 laryngoscopies in a full-scale patient simulator.

RESULTS

Although 89% of interviewed subjects claimed to know a classification to describe laryngeal view during laryngoscopy, 53% were able to name a classification. When specifically asked about the CL classification, 74% of the interviewed subjects stated to know this classification, whereas 25% could define all four grades correctly. In the simulator-based part of the study, inter-observer reliability was fair with a kappa coefficient of 0.35 and intra-observer reliability was poor with a kappa of 0.15.

CONCLUSIONS

The CL classification is poorly known in detail among anaesthesiologists and reproducibility even in subjects well familiar with this classification is limited.

The Internet as a diagnostic aid: the patients' perspective

A questionnaire-based cross-sectional study was conducted in order to determine how frequently patients attending a genitourinary (GU) medicine clinic use the Internet to diagnose their own symptoms, and to assess the accuracy of their diagnosis. Out of 223 symptomatic patients attending a GU clinic, 101 (45.3%) looked up their symptoms on the Internet. The age difference between those who looked up their symptoms and those who did not was not statistically significant ( P = 0.77). Twenty (19.8%) out of 101 patients diagnosed their own symptoms, and 14 (13.9%) patients made the correct diagnosis. Ninety-one (90.1%) patients used the Google® search engine as the starting point for their search.

Although the Internet plays an important role in providing health information, the variable quality of health information available limits its use as a diagnostic tool by patients.

Closed system anaesthesia – historical aspects and recent developments

Closed circuit anaesthesia was described decades ago but did not achieve wide popularity among anaesthesiologists mainly because reliable control of inspiratory gas concentrations was not possible. Recent innovations including fast gas analysers, electronically controlled dosage systems and algorithms for feedback control have made possible the development of sophisticated closed circuit ventilators designed for routine clinical practice. The main advantages comprise economic use of medical gases and volatile anaesthetics, reduction of anaesthetic gas loss into the atmosphere, improved airway acclimatization as well as estimations of oxygen consumption. This article reviews historical aspects, recent developments as well as advantages and limitations of closed system anaesthesia.

Kohlenmonoxid: toxisches Molekül mit antiinflammatorischen und zytoprotektiven Eigenschaften

Carbon monoxide arises during incomplete combustion of organic material, is incorporated into the circulation via the lungs and displaces oxygen from hemoglobin. Consecutively, symptoms of intoxication such as headache, vertigo, nausea, seizures and coma may result in a dose dependent fashion. Carbon monoxide is however also generated endogenously during heme degradation catalysed by heme oxgenase enzymes. The isoform hemeoxygenase-1 is inducible by oxidative stress and may mediate cytoprotection mainly attributable to endogenously produced carbon monoxide. Exogenous applied carbon monoxide has also been shown to confer protection in experimental studies. Meanwhile, in addition to the toxicological properties, antiinflammatory and cytoprotective effects of carbon monoxide have moved into the focus of scientific interest.

Partial liquid ventilation: effects of closed breathing systems, heat-and-moisture-exchangers and sodalime absorbers on perfluorocarbon evaporation

BACKGROUND AND OBJECTIVES

During partial liquid ventilation perfluorocarbons are instilled into the airways from where they subsequently evaporate via the bronchial system. This process is influenced by multiple factors, such as the vapour pressure of the perfluorocarbons, the instilled volume, intrapulmonary perfluorocarbon distribution, postural positioning and ventilatory settings. In our study we compared the effects of open and closed breathing systems, a heat-and-moisture-exchanger and a sodalime absorber on perfluorocarbon evaporation during partial liquid ventilation.

METHODS

Isolated rat lungs were suspended from a force transducer. After intratracheal perfluorocarbon instillation (10 mL kg(-1)) the lungs were either ventilated with an open breathing system (n = 6), a closed breathing system (n = 6), an open breathing system with an integrated heat-and-moisture-exchanger (n = 6), an open breathing system with an integrated sodalime absorber (n = 6), or a closed breathing system with an integrated heat-and-moisture-exchanger and a sodalime absorber (n = 6). Evaporative perfluorocarbon elimination was determined gravimetrically.

RESULTS

When compared to the elimination half-life in an open breathing system (1.2 +/- 0.07 h), elimination half-life was longer with a closed system (6.4 +/- 0.9 h, P 0.05) when compared to a closed system.

CONCLUSIONS

Evaporative perfluorocarbon loss can be reduced effectively with closed breathing systems, followed by the use of sodalime absorbers and heat-and-moisture-exchangers.

Partial liquid ventilation in acute salt water-induced lung injury

BACKGROUND AND OBJECTIVES

Salt-water aspiration results in pulmonary oedema and hypoxia. We tested the hypothesis that partial liquid ventilation has beneficial effects on gas exchange and rate of survival in acute and extended salt water-induced lung injury.

METHODS

Anaesthetized, ventilated rats (tidal volume 6 mL kg(-1), PEEP 5 cmH2O) received a tracheal salt-water instillation (3%, 8 mL kg(-1) body weight) and were randomly assigned to three groups (n = 10 per group). While lungs of Group 1 were gas-ventilated, lungs of Group 2 received a single perfluorocarbon instillation (30 min after the injury, 5 mL kg(-1) perfluorocarbon) and lungs of Group 3 received an additional continuous perfluorocarbon application into the treachea (5 mL kg(-1) h(-1)) Arterial blood gases were measured with an intravascular blood gas sensor.

RESULTS

Salt-water instillation resulted in a marked decrease in PaO2 values within 30 min (from 432 +/- 65 to 83 +/- 40 mmHg, FiO2 = 1.0, P < 0.01). Arterial oxygenation improved in all three groups irrespective of treatment. We observed no significant differences between groups in peak PaO2 and PaCO2 values.

CONCLUSIONS

Our results suggest that partial liquid ventilation has no additional beneficial effects on gas exchange after life-threatening salt water-induced lung injury when compared to conventional gas ventilation with positive end-expiratory pressure.

Lung contusion-lacerations after blunt thoracic trauma in children

Chest trauma in children is an indicator of injury severity and is associated with a high mortality rate. The aim of this study was to investigate the impact of pulmonary contusion-laceration on short and long-term outcome of pediatric patients after blunt thoracic trauma. A retrospective analysis of records of 41 children aged 10 months to 17 years who were treated for pulmonary and associated injuries between 1986 and 2000 was done concerning mode of injury, types of injuries, management and outcome. In addition, a follow-up investigation was performed 4.5+/-1 years after injury. Of the patients 27 were involved in motor vehicle accidents (MVA group) and 14 patients suffered other types of accidents (others group). The mean injury severity score (ISS) was 30+/-2 (range 9-75) with no significant difference between the groups. Patients from the MVA group suffered more frequently bilateral pulmonary lesions and needed more often chest tube placement ( p<0.05), 5 patients died (12%) all from the MVA group. The follow-up investigation of 34 patients showed unremarkable chest x-rays and normal lung function in all but 1 patient with bronchial asthma. In conclusion, children who recover after a pulmonary contusion-laceration trauma do not suffer from significant late respiratory problems.

Contraceptive knowledge and behavior of conventionalists, careerists, idealists, bouncers, desperadoes, and outsiders

The aim of the survey was to determine the contraceptive behavior and knowledge on contraceptive methods of adolescents. We defined six clusters according to personality, leisure activities, and sociodemographic characteristics: conventionalists, careerists, idealists, bouncers, desperadoes, and outsiders. 1010 Austrian adolescents aged 14-24 years participated in the survey. 96%-100% indicated that they were familiar with the condom and the contraceptive pill. The two most popular contraceptive methods cited were the condom (39%) and OC (34%). Whereas 40% of conventionalists reported that OC were their preferred method of contraception, 53% of idealists indicated that they preferred the condom. 66% of the desperadoes indicated that they considered the pill expensive. 85% of conventionalists and careerists believe that OC offer the best protection against pregnancy. Clusters with higher self-esteem and those with a higher educational level were more likely to believe that this method is unreliable. The results obtained indicate that outsiders, desperatoes, and bouncers show deficits in sex education; only careerists and idealists appeared to be better informed. Research on adolescent contraceptive behavior should drop the traditional stratifying criteria and appreciate the diversity of adolescent populations in order to be better able to classify adolescents according to their contraceptive attitudes.

Evidence-based guidelines for the management of genital chlamydial infection in general practice. (Leicestershire Chlamydia Guidelines Group)

BACKGROUND

Valid clinical guidelines can be effective in improving patient care. Genital Chlamydia trachomatis infection is the commonest curable sexually transmitted disease (STD) in England and Wales and is an important cause of pelvic inflammatory disease (PID), tubal infertility and ectopic pregnancy. No published guidelines exist on managing genital chlamydial infection in British general practice.

OBJECTIVE

We aimed to develop valid guidelines for the management of genital chlamydial infection for use in British general practice.

METHODS

A district-wide postal questionnaire survey was used to document current clinical practice. A critical review of the evidence concerning the management of genital chlamydial infection as it relates to British general practice was performed. The information gained from the critical review and survey was used to develop evidence-based guidelines within a multidisciplinary guideline recommendation group.

RESULTS

The guidelines covered the diagnosis, investigation, drug treatment and referral of adult male and female patients with genital chlamydial infection in general practice.

CONCLUSION

Valid guidelines for the management of genital chlamydial infection have been developed for use in British general practice. Appropriate dissemination and implementation of the guidelines should lead to earlier detection and treatment of men and women with chlamydial infection and thereby reduce the incidence of PID, tubal infertility and ectopic pregnancy in women.

A survey of contact tracing practice for sexually transmitted diseases in GUM clinics in England and Wales

We set out to determine current policy and practice in relation to contact tracing (partner notification) for sexually transmitted diseases (STDs) within genitourinary medicine (GUM) clinics in England and Wales. A confidential postal questionnaire survey of all GUM clinics in England and Wales was undertaken. Completed questionnaires were returned by 105 GUM clinics (a response rate of 65%). All respondents undertook routine contact tracing for gonorrhoea and chlamydia. The most popular method of contact tracing used was patient referral. The majority of contact tracing was undertaken by health advisers. Information on the time period over which contact tracing was undertaken showed wide variation. Audit data on the effectiveness of contact tracing in terms of the proportion of sexual contacts seen were available from only a minority of GUM clinics (33/79, 42%). Only chlamydia (24/79, 30%) and gonorrhoea (22/79, 28%) were the subject of any appreciable audit activity. There is wide variation in contact tracing policy and practice in GUM clinics in England and Wales. Audit of contact tracing effectiveness appears to be a minority activity. Further research is needed before an evidence-based approach to contact tracing can be implemented.

A model for the development of evidence-based clinical guidelines at local level--the Leicestershire Genital Chlamydia Guidelines Project

Clinical guidelines can be effective in achieving health gain when they are validly developed, disseminated and implemented appropriately. There is, however, a potential conflict between the need for validity through use of expert resources available at a national level, and implementation, which is undertaken at local level and depends on the local relevance of the guideline. This paper presents a model by which valid guidelines for the management of a given disease (genital chlamydial infection) by general practitioners can be developed at local level using the resources available to a district health authority department of public health. The model has three elements. First, a district-wide postal questionnaire survey was used to document current clinical practice. Secondly, a critical review of the evidence relating to the management of genital chlamydial infection as it relates to British general practice was performed. Thirdly, the information gained from the critical review and survey was used by a multidisciplinary group to develop evidence-based guideline recommendations. It is argued that the Leicestershire Genital Chlamydia Guidelines compare favourably with other recently published national guidelines in terms of their development and content. Local guideline development of guidelines for selected topics can be practical and appropriate.

GP's management of genital Chlamydia: a survey of reported practice

BACKGROUND

Genital chlamydial infection is the commonest curable sexually transmitted disease in the industrialized world. Little is known about how GPs manage this condition.

OBJECTIVES

We aimed to determine current knowledge concerning genital chlamydia among GPs and to establish how patients with this infection are managed in primary care.

METHODS

A confidential self-administered postal questionnaire survey was sent to all 494 GPs in one English health district (Leicestershire).

RESULTS

Completed questionnaires were returned by 290 GPs (a response rate of 59%). A much higher proportion of GPs had tested and/or treated female patients for chlamydia [70%, 95% confidence interval (CI) 64-75%] as opposed to male patients (20%, CI 15-25%). Female patients (70%, CI 64-75%) were also more likely to be managed in general practice than male patients (56%, CI 50-62%). A majority of GPs (66%, CI 60-72%) routinely used an appropriate method of testing for chlamydia although a high vaginal swab, an inappropriate method of testing, was used by a fifth of GPs (19%, CI 15-24%). A large number of different treatment regimes were used by GPs. The majority of GPs (85%, CI 79-89%) prescribed an appropriate antibiotic although few GPs (19%, CI 14-25%) specified a chlamydia treatment regime in accordance with accepted international guidelines with respect to drug, dosage and duration of therapy.

CONCLUSIONS

Female patients with known or suspected genital chlamydial infection are commonly managed in UK general practice. There is scope to improve the management of this infection in general practice.

Ultrasound diagnosis of birth-related spinal cord trauma: neonatal diagnosis and follow-up and correlation with MRI

Two neonates, one with complete and one with incomplete birth-related transection of the cervico-thoracic spinal cord, form the basis of this report. Ultrasound and MRI findings in primary diagnosis and follow-up are described. The aim of this contribution is to bring this serious birth complication to the attention of the reader, to present the obstetrical risk factors, to describe the clinical presentation of the newborns and to make suggestions to expand the field of indications for spinal sonography. The value of spinal ultrasound in the first six months of life is stressed, especially in comparison to MRI. For definitive assessment of the lesion (transectional or nontransectional) follow-up ultrasound studies for several weeks are required.

[Experience of parents in home monitoring of apnea for prevention of sudden infant death (SIDS)]

89 of 119 parents of infants with apnea home monitoring answered to a standard questionnaire concerning different aspects of home monitoring. In almost all cases the home monitoring was finished at the begin of the study, lasting from six months to 12 months. The indications for an apnea monitor were: apparent life threatening event (n = 8), SIDS-sibling (n = 24), sleep apnea syndrome (n = 40) and parents pressing request (n = 17). 90% of parents felt to have got enough information about the function of the apnea monitor (mostly Graseby MR-10 monitor) and what they have to do when there is an apnea alarm. 6% of parents changed the monitor because of technical problems. Most of the alarms were registrated by almost all parents between 24 h and 6 h. 35% of parents stimulated their infants in case of an apnea alarm gently to vigorously, one infant had a mouth to mouth resuscitation. Questions concerning the psychological and social impact of home monitoring on parents demonstrated that there was some stress like anxiety, sleep disturbances mainly in the mothers. We conclude from parents experience with apnea home monitoring the need for an adequate medical, technical and psychological support.

Quantification of Candida albicans morphology in vaginal smears

The morphology index (Mi) of Candida albicans cells was determined by microscopic image analysis in vaginal smears from 26 patients. The morphology of the cells typically showed a broad distribution of forms, but the mean Mi was greater than 2.0 in 23/26 instances, indicating a preponderance of pseudohyphal and hyphal forms. No association could be found between Mi and the clinical assessment of signs or symptoms of Candida infection. Comparison of these 26 patients with 43 others who had Candida-positive vaginal smears but with fewer than 15 fungal cells in the smear revealed significantly lower scores for vulvovaginal symptoms among the latter.