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P L McNicol

Publications and source records attributed to P L McNicol.

15 recordsLinked to original sources
PubMed2006

Effect of an anaesthesia department led critical care outreach and acute pain service on postoperative serious adverse events.

UNLABELLED: We examined whether a combined critical care outreach and acute pain service comprising both medical and nursing staff from the Department of Anaesthesia would decrease the incidence of postoperative serious adverse events in a hospital with an established Medical Emergency Team. We called this combined service IMPACT: Inpatient Management of acute Pain and Advice on Clinical Treatment. We conducted a prospective, before-and-after trial with a baseline phase (319 patients) of standard acute pain management followed by the IMPACT phase (271 patients), during which the IMPACT team systematically reviewed high-risk postoperative patients for the first three days after their return to the general wards. The incidence of serious adverse events decreased from 23 events per 100 patients to 16 events per 100 patients. The 30-day mortality decreased from 9% to 3%, p = 0.004. An acute pain service providing critical care outreach may improve postoperative outcome but the workload is considerable.

Aged↗
PubMed2004

The effect of critical care outreach on postoperative serious adverse events.

We proposed that critical care outreach would decrease the incidence of postoperative serious adverse events and so conducted a sequential cohort study with a surveillance-only phase (baseline) followed by an intervention phase. We studied high-risk patients in a large Australian hospital. A critical care qualified nurse reviewed patients for the first three days after return to the general wards. During the intervention phase the nurse intervened in patient care where appropriate. We examined the incidence of 11 categories of serious adverse events per 100 patients during the first three days on the general wards during the surveillance and intervention phases. The surveillance phase had 319 patients and the intervention phase 345 patients. In a subgroup analysis, there were four myocardial infarctions per 100 patients in the surveillance phase and seven per 100 patients during the intervention phase (95% confidence interval: 1-7 infarctions per 100 patients increase). For the other 10 serious adverse events there were 19 per 100 patients in the surveillance phase and 11 per 100 patients in the intervention phase (95% confidence interval: 4-11 serious adverse events per 100 patients decrease). Outreach may have led to greater detection of myocardial infarctions while reducing the incidence of other serious adverse events.

Aged↗
PubMed2001

Changes in plasma creatinine concentration after cardiac anesthesia with isoflurane, propofol, or sevoflurane: a randomized clinical trial.

BACKGROUND: Renal impairment often follows cardiac surgery. The authors investigated whether sevoflurane produces greater increases in plasma creatinine concentration than isoflurane or propofol after elective coronary artery surgery. METHODS: As part of maintenance anesthesia, including during cardiopulmonary bypass, patients were randomly allocated to receive one of three agents: isoflurane (n = 118), sevoflurane (n = 118), or propofol (n = 118). Fresh gas flows were 3 l/min. The preoperative plasma creatinine concentration was subtracted from the highest creatinine concentration in the first 3 postoperative days. A median maximum increase greater than 44 microM (0.5 mg/dl) was regarded as clinically important. Data were analyzed on an intention-to-treat basis. Subgroup analyses were performed on per-protocol patients and those with preoperative renal impairment (creatinine concentration > 130 microM [1.47 mg/dl] or urea > 7.7 mM [blood urea nitrogen, 21.6 mg/dl]). RESULTS: The differences between the groups were small, clinically unimportant, and not statistically significant for the primary analysis and subgroups. The proportions of patients with creatinine increases greater than 44 microM were 15% in the isoflurane group, 17% in the sevoflurane group, and 11% in the propofol group (P = 0.45). The median increases were 8 microM in the isoflurane group, 4 microM in the sevoflurane group, and 6 microM in the propofol group. The differences between the three median maximum increases were 1-4 microM (P > 0.45). In the subgroup with preoperative renal impairment, the median increases were 10 microM in the isoflurane group, 15 microM in the sevoflurane group, and 5 microM in the propofol group (P = 0.72). CONCLUSIONS: Sevoflurane did not produce greater increases in creatinine than isoflurane or propofol after elective coronary artery surgery.

Aged↗
PubMed2000

Postoperative fibrinolysis diagnosed by thrombelastography.

Thrombelastography is a useful method for the monitoring of bedside coagulation, especially for fibrinolysis. We report a case where thrombelastography facilitated early detection of fibrinolysis with significant clinical bleeding in a patient immediately following hip replacement surgery. The early diagnosis enabled institution of antifibrinolytic therapy and monitoring of the patient's response. It is likely to have led to less blood product transfusion and may possibly have prevented unnecessary surgical re-exploration.

Aged↗
PubMed2000

Prediction of the mediastinal drainage after coronary artery bypass surgery.

Using multiple correlation and linear regression approaches, we investigated the association between the amount of mediastinal drainage for the first 24 postoperative hours and clinical variables as well as multiple haematological tests performed at three time points: before anaesthesia induction, 10 minutes after protamine administration and just after skin closure, on 46 patients undergoing primary coronary artery bypass grafting. Three models from the three times were then developed to predict mediastinal drainage. The number of internal mammary grafts, the total number of grafts and plasma fibrinogen concentration were useful predictors of mediastinal drainage at all three times. The platelet count taken only after skin closure was found to provide additional predictive information. Each regression model explained approximately 60% of the variation in postoperative mediastinal drainage. The information obtained from these predictive models is useful in defining high-risk populations.

Aged↗
PubMed2000

The epidemiology of major early adverse physiological events after surgery.

OBJECTIVE: To study the incidence of major post-operative adverse physiological events in a tertiary hospital. METHODS: Non-cardiac, surgical in-patients were studied for the first three post-operative days. Daily assessment was by patient visit, chart review and laboratory result analysis. Pre-determined diagnostic criteria for the identification of adverse physiological events were used. RESULTS: One hundred and seven patients were studied. The mean age was 61 +/- 20 years. Forty-four were female and 63 were male. Pre-operatively, 48 patients had one or more of 34 different co-morbidities. Forty three (40%) of the 107 patients had one or more major adverse physiological events. These events included hypotension 24 (22%), altered mental state 16 (15%), oliguria 9 (8.4%), abnormal heart rate 8 (7.5%) and abnormal respiratory rate 5 (4.7%). Morbidity associated with these events included respiratory failure 5 (4.7%), prolonged altered mental state 5, (4.7%), and septic shock 3 (2.8%). There were two deaths. Adverse physiological events were common in thoracic 5/9 (56%), neurosurgical 4/10 (40%) and vascular 8/13 (62%) patients. Prolonged altered mental state was most common among orthopaedic patients 5/22 (23%). Adverse physiological events were more frequent in the elderly than the young: 14/52 (27%) in those who were less than 65 years of age versus 29/55 (53%) in those who were 65 years and older (p < 0.025). There was a non-significant increase (p < 0.1) in adverse physiological events in patients having emergency surgery 16/28 (57%) compared with those having elective surgery 27/79 (34%). CONCLUSIONS: This study reveals a high incidence of post-operative adverse physiological events in surgical patients in a university teaching hospital and identifies several high-risk groups. Further studies are needed to define the clinical significance of these events, appropriate management and prognosis.

Journal Article↗
PubMed1999

The Effect of Preoperative Aspirin and/or Heparin Therapy on Coagulation and Postoperative Blood Loss after Coronary Artery Bypass Surgery.

OBJECTIVE: To assess the effects of preoperative aspirin and/or intravenous heparin therapy on perioperative coagulation tests and postoperative blood loss for 24-hour after coronary artery bypass surgery. METHODS: Multiple conventional coagulation tests, activated clotting time, thrombelastograph, skin bleeding time and platelet aggregation were performed before induction of anaesthesia, following protamine administration and after skin closure in 45 patients. RESULTS: There was no significant difference in either coagulation tests or postoperative blood loss (median of 860 mL with a range of 275 to 2800 mL, versus 833 ml with a range of 500-1380 mL) between the aspirin and no-aspirin patients. Preoperative heparin therapy affected most coagulation tests (e.g. international normalised ratio, activated partial thromboplastin time, thrombin clotting time, prothrombin time, activated clotting time and coagulation time of thrombelastography) before anaesthesia. The effects disappeared following protamine administration and after skin closure. Post operative blood loss was not significantly increased for the heparin group compared with the no-heparin group (median of 850 mL with a range of 700-1400 mL, versus 856 mL with a range of 275-2800 mL, respectively). Similar results were seen in patients receiving preoperative co-administration of aspirin and heparin compared with patients receiving aspirin alone. There was no suppression of platelet activity in patients receiving preoperative heparin or co-administration of aspirin and heparin. However, such suppression was found in patients receiving aspirin only. CONCLUSION: This study suggests that preoperative aspirin ingestion and intravenous heparin therapy should be administered as indicated and that concerns about the risk of postoperative bleeding should not lead to modification or cessation of such therapy.

Journal Article↗
PubMed1996

Orthotopic liver transplantation in two patients with hypertrophic obstructive cardiomyopathy.

Orthotopic liver transplantation (OLT) in patients with end-stage liver disease is a procedure associated with high cardiac output, low systemic vascular resistance (SVR), coagulopathy and the potential for significant blood loss. A feature of hypertrophic obstructive cardiomyopathy (HOCM) is left ventricular outflow tract obstruction which may be exacerbated by reduced SVR, reduced filling pressures, tachycardia and positive inotropy. We report two cases of OLT in patients with HOCM. Our anaesthetic technique involved the use of halothane and vecuronium and avoidance of drugs causing tachycardia and positive inotropy. Management was aided by intraoperative transoesophageal echocardiography which showed that filling pressures poorly reflected end-diastolic volumes. Volume administration, vasoconstrictors and avoidance of inotropes and chronotropes reduced the outflow tract obstruction which was particularly severe in the reperfusion period.

Anesthesia, General↗
PubMed1995

Bupivacaine enantiomer pharmacokinetics after intercostal neural blockade in liver transplantation patients.

Bupivacaine, being a racemic local anesthetic, exists as an equal mixture of its component enantiomers R(+)- and S(-)-bupivacaine, which behave pharmacokinetically as independent drugs after injection into the body. Intercostal neural blockade using bupivacaine was performed for postoperative analgesia in 12 patients after orthotopic liver transplantation. Arterial blood, sampled serially, was assayed by enantioselective high-performance liquid chromatography for R(+)- and S(-)-bupivacaine. The average of the simultaneous R(+):S(-) ratios of blood bupivacaine concentrations in the 12 patients was 0.74 (SD 0.11); however, the use of a population mean value or a mean value for any patient denies the time-dependence of this entity. The blood enantiomer concentration difference was reflected in the maximum measured concentrations which, after the first dose, were, respectively, 0.38 (SD 0.19) and 0.52 (SD 0.28) mg.L-1.100 mg-1 RS-bupivacaine administered (P = 0.0003). The difference in blood concentrations between the enantiomers, reflected by the R(+):S(-) ratio being less than unity, could be explained by a greater mean total body clearance and a larger apparent volume distribution of R(+)-bupivacaine. Elimination of both enantiomers was prolonged in these patients after liver transplantation compared to data from the literature, but there was no tendency for either enantiomer to accumulate selectively, even upon repeated dosing. We conclude that this demonstration of differences in pharmacokinetics (and, in laboratory studies, also in pharmacodynamics) between the bupivacaine enantiomers points to the need for future studies to recognize the enantiomeric duality of this local anesthetic.

Bupivacaine↗
PubMed1994

Patterns of coagulopathy during liver transplantation: experience with the first 75 cases using thrombelastography.

Using both conventional laboratory clotting profile and thrombelastography, coagulation status was monitored intraoperatively during liver transplantation in the first 75 cases performed at the Austin Hospital between June 1988 and October 1992. Superimposed on a baseline coagulopathy due to liver disease is a specific pattern of coagulation disturbance which occurs during a liver transplant. Fibrinolysis occurs in the anhepatic stage, worsens with early reperfusion and then spontaneously resolves. In addition reperfusion is associated with a transient clotting defect. If blood loss is excessive, coagulopathy due to massive transfusion may compound the situation. Thrombelastography is a measurement technique allowing rapid on-site assessment of functional clotting status. It is particularly useful in liver transplant surgery. In combination with clinical bleeding assessment it facilitates selective use of component therapy (fresh frozen plasma, platelets and cryoprecipitate) and specific drug treatment only when it is appropriate. It also acts as a liver function test, being especially useful in assessing the graft after reperfusion.

Blood Coagulation↗
PubMed1994

Blood loss and transfusion requirements in liver transplantation: experience with the first 75 cases.

The blood loss data and transfusion requirements including blood bank, salvaged washed red cells, fresh frozen plasma and cryoprecipitate were analysed for the first 75 cases of liver transplantation performed at the Austin Hospital between June 1988 and October 1992. The mean blood loss was 8.8 litres (standard deviation 14.1) with a median value of 4.0 litres. Blood product use expressed as mean number of units (SD) was bank red blood cells 7.1 (12.7), washed red blood cells 3.9 (5.9), fresh frozen plasma 7.1 (9.1), platelets 5.1 (7.4), and cryoprecipitate 1.7 (5.1). These results demonstrate that liver transplantation can be performed without imposing excessive demands on blood transfusion services. Management should include surgical techniques to minimize bleeding and use of autologous transfusion. Use of component therapy (FFP, platelets and cryoprecipitate) should not be empirical. It should be selective on the basis of clinical bleeding assessment and guided by results of the laboratory coagulation profile and changes in thrombelastographic (TEG) parameters.

Adolescent↗