The development of a performance indicator to objectively monitor the quality of care provided by an acute pain team.

Quality assurance procedures are essential in the maintenance of clinical standards in medicine. Conventional analysis techniques have difficulty in detecting gradual changes over time. Cumulative sum techniques monitor the frequency with which an event occurs and can detect changes in its frequency as soon as they become statistically significant. This study explores the use of cumulative sum techniques to monitor the performance of an acute pain team in a teaching hospital. It shows that periods of suboptimal performance can be readily identified. The prospective use of these techniques in clinical audit may allow the earlier identification and correction of technical or organisational problems. These should lead to improvements in patient care and satisfaction.

Resuscitation of critically ill patients based on the results of gastric tonometry: a prospective, randomized, controlled trial.

OBJECTIVE: To determine whether additional therapy aimed at correcting low gastric intramucosal pH (pHi) improves outcome in conventionally resuscitated, critically ill patients. DESIGN: Prospective, randomized, controlled study. SETTING: General intensive care unit (ICU) of a university teaching hospital. PATIENTS: A total of 210 adult patients, with a median Acute Physiology and Chronic Health Evaluation II score of 24 (range, 8-51). INTERVENTIONS: All patients were resuscitated according to standard guidelines. After resuscitation, those patients in the intervention group with a pHi of <7.35 were treated with additional colloid and then dobutamine (5 microg/kg/min then 10 microg/kg min) until 24 hrs after enrollment. MEASUREMENTS AND MAIN RESULTS: There were no significant differences (p > .05) in ICU mortality (39.6% in the control group vs. 38.5% in the intervention group), hospital mortality (45.3% in the control group vs. 42.3% in the intervention group), and 30-day mortality (43.7% in the control group vs. 40.2 in the intervention group); survival curves; median modified maximal multiorgan dysfunction score (10 points in the control group vs. 13 points in the intervention group); median modified duration of ICU stay (12 days in the control group vs. 11.5 days in the intervention group); or median modified duration of hospital stay (60 days in the control group vs. 42 days in the intervention group). A subgroup analysis of those patients with gastric mucosal pH of > or =7.35 at admission revealed no difference in ICU mortality (10.3% in the control group vs. 14.8% in the intervention group), hospital mortality (13.8% in the control group vs. 29.6% in the intervention group), or 30-day mortality (10.3% in the control group vs. 26.9% in the intervention group). CONCLUSIONS: The routine use of treatment titrated against pHi in the management of critically ill patients cannot be supported. Failure to improve outcome may be caused by an inability to produce a clinically significant change in pHi or because pHi is simply a marker of disease rather than a factor in the pathogenesis of multiorgan failure.

A survey of undergraduate teaching in anaesthesia.

Currently, no well accepted and clearly defined 'core' curriculum for undergraduate anaesthesia, teaching exists. To address this deficiency, we surveyed 73 university departments of anaesthesia and intensive care. Sixty-five replied from South-east Asia (12), Australasia (13), the UK and Ireland (28) and Canada (12). A questionnaire containing 37 items ranging from departmental structure to curriculum content was used. We found significant regional differences. Overall, most departments taught pharmacology of anaesthetic drugs (83%), pre-operative assessment (92%) and care of the unconscious patient (77%). Ninety-seven per cent taught airway management and intubation and 80% taught intravenous cannulation. Basic life support was taught by 92% and advanced life support by 71%. Fewer than half taught advanced trauma life support principles (44%). Critical care teaching was less well defined, but a consensus of schools taught respiratory failure and ventilation, management of circulatory shock and principles of sepsis and multi-organ system failure. Practical clinical skills were taught mainly using patients and simulators, 46% had a skills laboratory and six employed a resuscitation officer. However, it should be noted that we did not assess the quality and outcome of teaching.

Long-term outcome and functional health status following intensive care in Hong Kong.

OBJECTIVES: To assess mortality and functional health status of patients at 1 yr following admission to a multidisciplinary intensive care unit (ICU) in Hong Kong. To determine which factors are associated with a poor long-term outcome. DESIGN: Prospective data collection and review. SETTING: A 14-bed multidisciplinary ICU in a 1,400-bed tertiary care university hospital. PATIENTS: Data from 2,268 consecutive patients admitted over a 2.5-yr period was analyzed, including follow-up at 1 yr in 853 adult survivors. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The patients' clinical details and Acute Physiology and Chronic Health Evaluation (APACHE) II scores were recorded on day 2 of admission and reviewed at time of discharge or death. The mean APACHE II score on admission was 18. Survival status at 1 yr was ascertained and the sickness impact profile (SIP) scored as a measure of functional health status for survivors. Sixty-five percent of patients survived to discharge from hospital and 44% of patients were known to survive to 1 yr; 6% of patients could not be traced at 1 yr. Functional health status was assessed in 85% of eligible adult patients. Survivors to 1 yr were younger than nonsurvivors and had lower APACHE II scores. The median SIP score was 5.1, (25th and 75th percentiles: 0 to 15), and 76% of patients had SIP scores < or = 15, i.e., normal health to moderate disability. Five percent of the patients were not working or had retired for health-related reasons. Stepwise logistic regression to identify factors associated with poor functional health status defined as a SIP score >15 at 1 yr found increasing age, cardiac/ respiratory arrest, intracranial hemorrhage, and trauma to be associated with poor outcomes. A correlation was found between APACHE II scores and SIP scores (Spearman's correlation coefficient = 0.13, p < .001). CONCLUSIONS: The SIP scores indicated that the majority of patients who survived to 1 yr after ICU admission enjoyed reasonable functional health status. A poor functional health status at 1 yr did not relate to the severity of the acute illness suffered, but appeared to relate to the prognosis of the underlying disease process.

Incident reporting in acute pain management.

Incident reporting is an effective tool for continuous quality improvement in clinical practice. A prospective study on voluntary incident reporting in pain management was conducted at a major teaching hospital in Hong Kong. Over a 12-month period, 53 incidents were reported in 1275 patients who received pain relief treatments which were supervised by the acute pain service. The majority of the incidents were first detected by the pain team. The most common incidents involved delivery circuits, delivery pump and drug administration. A large proportion (81.4%) of the incidents were thought to be preventable. Human factors were involved in 41.9% of the patients reported, most commonly associated with unfamiliar technique/inexperience, inattention and inadequate communication. Four patients developed major morbidity of which two were attributed to inadequate analgesia, while three others had major physiological changes without morbidity. Strategies have been formulated to prevent further occurrence of these incidents. We propose that incident reporting is a potentially useful tool in identifying and preventing adverse events in postoperative pain management.

A comparison of the Hamamatsu NIRO 500 and the INVOS 3100 near-infrared spectrophotometers.

Near-infrared spectroscopy is a technique used for non-invasive measurement of cerebral oxygenation and a number of commercial devices are currently available for use. We compared measurements of cerebral oxygenation made with two near-infrared spectrophotometers--the Somanetics Invos 3100 cerebral oximeter and the Hamamatsu NIRO-500 near-infrared spectrophotometer. Hypoxia was induced in six healthy male volunteers with and without occlusion of scalp blood flow. Oxygen saturation, end-tidal carbon dioxide tension, regional cerebral oxygen saturation, change in regional cerebral oxyhaemoglobin concentration and change in regional cerebral total haemoglobin concentration were measured. The INVOS 3100 displays cerebral oxygen saturation directly. The NIRO-500 displays change in total haemoglobin concentration and oxyhaemoglobin concentration, and the cerebral oxygen saturation was calculated offline. Statistical analysis disproved the assumption that the INVOS 3100 and the NIRO-500 were measuring the same changes in cerebral oxygenation. Neither machine can be confirmed for reliability against a gold standard and operational difficulties mean that neither can be recommended for routine clinical use.

Anaesthetic implications of Maffucci's syndrome.

Maffucci's syndrome is a rare, congenital disease due to neuro-ectodermal dysplasia and is characterized by enchondromatosis and multiple soft tissue haemangiomata. A case of Maffucci's syndrome with haemangiomata along the upper airways requiring laser surgery is described. The literature on Maffucci's syndrome is reviewed.

The state of health and provision of health care in Hong Kong.

In 1997, Hong Kong became a Special Administrative Region of the People's Republic of China. The new government took control of a Western style health-care system and a population whose health is comparable to the rest of the developed world. This article describes the existing health-care system, the state of public health and some of the challenges and opportunities facing the new administration.

Translation and calibration of a Chinese version of the Sickness Impact Profile for use in Hong Kong.

Because of the lack of suitable generic health status measures in Hong Kong that reflect the value structure and culture of the society, we have translated and calibrated the Sickness Impact Profile, which was originally developed in the United States. Translation consisted of a sequence of forward translations into Chinese, back translations into English and, when there was a loss of meaning or conceptual equivalence, retranslation into Chinese. Sixty Hong Kong Chinese people, including health professionals, patients, and members of the public were then recruited to determine item and dimension weights for the Hong Kong population. Individual ratings were averaged to obtain a consensus value for each item. Within-category reliability analysis for scores varied from 0.70 to 0.92 (Cronbach's alpha values) and overall internal consistency was 0.98. There were only small differences between this version and the original American English version in the ratings given to individual questions (Pearson's product moment correlation coefficient, r=0.8). We have developed a Chinese translation of the Sickness Impact Profile, which can now be used to evaluate health outcomes in Hong Kong and to compare outcomes with studies in other populations where the Sickness Impact Profile was used.

Intermittent bolus dosing of ceftazidime in critically ill patients.

Ceftazidime is frequently used in critically ill patients, particularly for the treatment of Pseudomonas aeruginosa infections. The recommended dosing regimen is based on pharmacokinetic data obtained in healthy volunteers and may not be appropriate in the critically ill. We administered ceftazidime in the maximum recommended dose (2 g i.v. every 8 h) to ten critically ill patients with normal plasma creatinine. Eighteen arterial blood samples were taken from each patient over the first 8 h for measurement of ceftazidime concentrations and subsequent compartmental pharmacokinetic analysis. An additional trough sample was taken from each patient on day 3. Although mean pharmacokinetic variables did not differ from previously reported data in normal volunteers there was wide variability in plasma drug concentrations. Three of our patients had plasma ceftazidime concentrations less than the MIC for P. aeruginosa (8 mg/L) and nine had concentrations less than 5 x MIC, which has been recommended to ensure efficacy. On day 3 trough ceftazidime concentrations were less than the MIC in four out of the seven patients in whom measurements were made and less than 5 x MIC in the remaining three. There was no clinical predictor of which patients would have low plasma concentrations. Our results show that plasma concentrations of ceftazidime are very variable when the recommended intermittent bolus dosing regimen is used and may result in inadequate plasma concentrations of drug in critical infections. This may result in treatment failure and the emergence of antibiotic resistance. A loading dose followed by continuous infusion should overcome these problems but this awaits in-vivo evaluation.

Gastric tonometry and prediction of outcome in the critically ill. Arterial to intramucosal pH gradient and carbon dioxide gradient.

Splanchnic ischaemia is thought to be of central importance in the development of multi-organ failure and hence death in critically ill patients. It has been suggested that the arterial to gastric intramucosal pH gradient and the difference in partial pressure of carbon dioxide between gastric mucosa and arterial blood are more sensitive markers of splanchnic ischaemia than gastric intramucosal pH itself and thus should be predictors of mortality in the critically ill. We studied 62 critically ill patients within 6 h of admission to the intensive care unit and found no significant difference at 0, 12 or 24 h after admission to the study in either the arterial to gastric intramucosal pH gradient or the difference in partial pressure of carbon dioxide between gastric mucosa and arterial blood between survivors and nonsurvivors. We conclude that in contrast to gastric intramucosal pH neither the arterial to gastric intramucosal pH gradient nor the difference in partial pressure of carbon dioxide between gastric mucosa and arterial blood distinguish survivors from nonsurvivors.

Critical incident reporting in the intensive care unit.

Critical incident reporting was introduced into the intensive care unit (ICU) as part of the development of a quality assurance programme within our department. Over a 3-year period 281 critical incidents were reported. Factors relating to causation, detection and prevention of critical incidents were sought. Detection of a critical incident in over 50% of cases resulted from direct observation of the patient while monitoring systems accounted for a further 27%. No physiological changes were observed in 54% of critical incidents. The most common incidents reported concerned airway management and invasive lines, tubes and drains. Human error was a factor in 55% of incidents while violations of standard practice contributed to 28%. Critical incident reporting was effective in revealing latent errors in our "system' and clarifying the role of human error in the generation of incidents. It has proven to be a useful technique to highlight problems previously undetected in our quality assurance programme. Improvements in quality of care following implementation of preventative strategies await further assessment.

Opioid requirements and responses in Asians.

The provision of good analgesia can be influenced by ethnic differences in how pain is expressed, the attitudes of patients and health professionals towards pain management and pharmacological differences in the responses to opioids. It is difficult to generalize results so that they are applicable to any ethnic group as a whole. There is also the question of how best to categorize ethnic Asians who have been in Australasia for several generations. Much of the pharmacogenetic work has focused on the metabolism of codeine, morphine and pethidine, and there are some differences between Chinese and Caucasians. Asians may receive less analgesia because they are more likely to experience, or are less tolerant of the adverse effects of opioids. Despite this, ethnic factors are probably only a small contributor to the inter-individual variation in opioid requirements. Unlike earlier studies, recent larger studies using patient-controlled analgesia have shown similar opioid usage between Asians and Caucasians in the postoperative period. An individualized pain management program is essential for any patient, whatever his or her ethnic origin. The use of patient-controlled analgesia will minimize some of the problems that may occur because of poor communication between the patient and the healthcare staff. Nevertheless, in a multicultural society like Australia's, health professionals should be conscious of the many factors that may influence the effects of prescribed treatment to manage pain in different ethnic groups.

Improvements in anaesthetic care resulting from a critical incident reporting programme.

The rôle of an anaesthetic incident reporting programme in improving anaesthetic safety was studied. The programme had been running for 4 to 5 years in three large hospitals in Hong Kong and more than 1000 incidents have been reported. The number of reports being made and frequency of the various categories of incident reported, did not alter during the study period. Sixty nine percent of incidents were considered to be preventable. Human error contributed to 76% of incidents and violations of standard practice to 30% of incidents. The programme was effective in its ability to detect latent errors in the anaesthesia system and when these were corrected, incidents did not recur. The frequency with which various contributing factors were cited did not decrease with time. With the exception of problems dealt with by specific protocol development, the study found no evidence that an increasing awareness of the problem of human error was effective in reducing this kind of problem.

Comparison of intrathoracic and intra-abdominal measurements of central venous pressure.

BACKGROUND: Complications can arise from standard intrathoracic central venous pressure (CVP) measurements in critically ill, mechanically ventilated patients. We have assessed the feasibility of catheterisation by the femoral route to measure CVP in the abdomen (ACVP). We compared measurements by the standard jugular or subclavian route (TCVP) with simultaneous ACVP measurements by the femoral route. METHODS: Between June, 1994 and May, 1995, we recruited 20 critically ill adult patients with various disorders; all patients already had a TCVP line in situ. We placed a femoral catheter in the inferior vena cava close to the right atrium under electrocardiographic guidance. The catheter position was confirmed (and corrected if necessary) by chest radiography. CVP was measured from both sites hourly for 6 h. Positive end-expiratory pressure, mean airway pressure, and intra-abdominal pressure were recorded simultaneously. FINDINGS: One patient was excluded because radiography showed that the catheter position was incorrect. For 133 paired measurements of ACVP and TCVP in the remaining 19 patients, the mean difference was 0.45 mm Hg (SD 0.89: 95% Cl 0.30-0.60); the limits of agreement were -1.33 to 2.23 mm Hg (-1.63 to 2.53). We found a small tendency for the difference between ACVP and TCVP to increase as positive end-expiratory pressure and mean airway pressure increased; the difference was statistically, but not clinically, significant. INTERPRETATION: Our study showed that for clinical purposes CVP can be measured by a femoral catheter placed in the abdominal inferior vena cava near the right atrium. This approach can replace standard TCVP measurements in critically ill, mechanically ventilated patients.

Superimposed inspiratory work of the Siemens Servo 300 ventilator during continuous positive airway pressure.

OBJECTIVE: To compare the superimposed inspired work of breathing (SIW) of the Siemens Servo 300 ventilator with the Siemens Servo 900 C ventilator. DESIGN: Comparisons made at continuous positive airway pressure (CPAP) levels of 0, 4, and 8 cmH2O, and at trigger sensitivities of -1 and -2 cmH2O, and flow triggering. SETTING: General intensive care unit in a University teaching hospital. PATIENTS: 7 patients receiving CPAP. At all levels of CPAP, the SIW was significantly less with the Siemens Servo 300 ventilator as compared to the Siemens Servo 900 C ventilator despite similar trigger sensitivities. No significant difference was found in the SIW of the Servo 300 ventilator when comparing trigger sensitivities of -1 cmH2O, -2 cmH2O, and flow triggering. Different levels of CPAP had no effect on SIW. CONCLUSIONS: The Siemens Servo 300 ventilator entails less superimposed inspiratory work of breathing than the Siemens Servo 900 C ventilator.

Pressure support ventilation during isoflurane anaesthesia.

We have studied the respiratory effects of 5 and 10 cmH2O pressure support ventilation during anaesthesia with 1.5% end-tidal concentration of isoflurane in nine healthy, spontaneously breathing, adult patients. Some of the patients demonstrated an irregular respiratory pattern with periods of apnoea and we therefore went on to study a further seven patients with a continuous 500 s recording of airflow. Pressure support ventilation augmented mean (SD) tidal volume from 212 (56) ml to 360 (88) ml at 5 cmH2O and to 509 (108) ml at 10 cmH2O (n = 16, p < 0.05). Mean (SD) respiratory rate decreased from 26 (6) min-1 to 22 (6) min-1 at 5 cmH2O and 17 (5) min-1 at 10 cmH2O pressure support (n = 16, p < 0.05). Mean (SD) inspiratory work of breathing decreased from 1.77 (0.70) J. min-1 to 0.31 (0.36) J.min-1 at 5 cmH2O and 0.16 (0.26) J.min-1 at 10 cmH2O pressure support ventilation (n = 9, p < 0.05). Analysis of the respiratory rhythm in the second group of seven patients revealed an oscillating respiratory pattern in four patients at 5 cmH2O and six of the seven patients at 10 cmH2O pressure support ventilation. The metabolic advantage of the decreased work of breathing during pressure support ventilation during anaesthesia is unlikely to balance the disadvantage of an oscillating respiratory rhythm.

Severe hyperventilation and respiratory alkalosis during pressure-support ventilation: report of a hazard.

A 53-year-old woman with a flaccid quadriparesis developed severe hyperventilation and respiratory alkalosis during pressure-support ventilation. A gas leak in the ventilator system caused a loss of positive end-expiratory pressure and autocycling of the ventilator. Large ventilator breaths were then delivered because a high level of pressure support was set in a patient with low respiratory impedance. The complication is rare and its occurrence requires a combination of patient and equipment factors. Awareness of the responsible factors will promote detection and prevention of the hazard.