Attitudes towards risk-reducing early salpingectomy with delayed oophorectomy for ovarian cancer prevention: a cohort study.

OBJECTIVE: To determine risk-reducing early salpingectomy and delayed oophorectomy (RRESDO) acceptability and effect of surgical prevention on menopausal sequelae/satisfaction/regret in women at increased ovarian cancer (OC) risk. DESIGN: Multicentre, cohort, questionnaire study (IRSCTN:12310993). SETTING: United Kingdom (UK). POPULATION: UK women without OC ≥18 years, at increased OC risk, with/without previous RRSO, ascertained through specialist familial cancer/genetic clinics and BRCA support groups. METHODS: Participants completed a 39-item questionnaire. Baseline characteristics were described using descriptive statistics. Logistic/linear regression models analysed the impact of variables on RRESDO acceptability and health outcomes. MAIN OUTCOMES: RRESDO acceptability, menopausal sequelae, satisfaction/regret. RESULTS: In all, 346 of 683 participants underwent risk-reducing salpingo-oophorectomy (RRSO). Of premenopausal women who had not undergone RRSO, 69.1% (181/262) found it acceptable to participate in a research study offering RRESDO. Premenopausal women concerned about sexual dysfunction were more likely to find RRESDO acceptable (odds ratio [OR] = 2.9, 95% CI 1.2-7.7, P = 0.025). Women experiencing sexual dysfunction after premenopausal RRSO were more likely to find RRESDO acceptable in retrospect (OR = 5.3, 95% CI 1.2-27.5, P < 0.031). In all, 88.8% (143/161) premenopausal and 95.2% (80/84) postmenopausal women who underwent RRSO, respectively, were satisfied with their decision, whereas 9.4% (15/160) premenopausal and 1.2% (1/81) postmenopausal women who underwent RRSO regretted their decision. HRT uptake in premenopausal individuals without breast cancer (BC) was 74.1% (80/108). HRT use did not significantly affect satisfaction/regret levels but did reduce symptoms of vaginal dryness (OR = 0.4, 95% CI 0.2-0.9, P = 0.025). CONCLUSION: Data show high RRESDO acceptability, particularly in women concerned about sexual dysfunction. Although RRSO satisfaction remains high, regret rates are much higher for premenopausal women than for postmenopausal women. HRT use following premenopausal RRSO does not increase satisfaction but does reduce vaginal dryness. TWEETABLE ABSTRACT: RRESDO has high acceptability among premenopausal women at increased ovarian cancer risk, particularly those concerned about sexual dysfunction.

A randomised controlled trial of peri-operative lidocaine infusions for open radical prostatectomy.

We allocated 76 men scheduled for radical retropubic prostatectomy to peri-operative lidocaine 2% or saline 0.9%: a pre-operative 0.075 ml.kg(-1) intravenous bolus; an intra-operative intravenous infusion at 0.075 ml.kg(-1) .h(-1) ; and 24 hours' postoperative subcutaneous infusion at 0.075 ml.kg(-1) .h(-1) . Lidocaine reduced the postoperative hospital stay by a mean (95% CI) of 1.3 (0.3-2.4) days, p = 0.017, from a mean (SD) of 4.6 (3.2) days with saline. There were no significant differences in pain at rest or on coughing at 24 h. [corrected]. Lidocaine reduced 24-h morphine consumption by a mean (95% CI) of 13.9 (2.2-25.7) mg, p = 0.021, from a mean (SD) of 52.3 (26.9) mg with saline. There were no differences in other outcomes.

The effects of plasmalyte-148 vs. Hartmann's solution during major liver resection: a multicentre, double-blind, randomized controlled trial.

BACKGROUND: The acid-base, biochemical and hematological effects of crystalloid solutions have not been comprehensively evaluated in patients with liver resection. DESIGN: multicenter, prospective, double-blind randomized controlled trial investigating the biochemical effects of Hartmann's solution (HS) or Plasmalyte-148 (PL) in 60 patients undergoing major liver resection. PRIMARY OUTCOME: base excess immediately after surgery. SECONDARY OUTCOMES: changes in blood biochemistry and hematology. RESULTS: At completion of surgery, patients receiving HS had equivalent mean standard base excess (-1.7±2.2 vs. -0.9±2.3 meq/L; P=0.17) to those treated with PL. However, patients treated with HS were more hyperchloremic (difference 1.7 mmol/L, 95% CI: 0.2 to 3.2, P=0.03) and hyperlactatemic (difference 0.8 mmol/L, 95% CI: 0.2 to 1.3; P=0.01). In contrast, patients receiving PL had higher mean plasma magnesium levels and lower ionized calcium levels. There were no significant differences in pH, bicarbonate, albumin and phosphate levels. Immediately after surgery, mean PT and aPTT were significantly lower in the PL group. Intraoperatively, the median (IQR) blood loss in the PL group was 300 mL (200:413) vs. 500 mL (300:638) in the HS group (P=0.03). Correspondingly, the postoperative hemoglobin was higher in the PL group. Total complications were more frequent in the HS Group (56% vs. 20%, relative risk 2.8; 95% CI: 1.3 to 6.1; P=0.007). CONCLUSION: In liver resection patients, HS and PL led to similar base excess values but different post operative plasma biochemistry and hematology values. Understanding of these effects may help clinicians individualize fluid therapy in these patients.

Effect of perfusion pressure on the splanchnic circulation after CPB: a pilot study.

BACKGROUND: The impact of different blood pressure targets is unknown for post cardiac surgery patient in the intensive care unit. We, therefore, investigated the effects of a mean arterial pressure (MAP) target of 65 or 85 mmHg on splanchnic oxygenation, metabolic function, cytokine regulation and gastric tonometry after cardiopulmonary bypass. METHODS: Sixteen patients were randomized to the HLH group (high-low-high) where MAP of 85-65-85 mmHg was targeted or the LHL group where MAP 65-85-65 mmHg was targeted with norepinephrine infusion. RESULTS: MAP targets were achieved in all patients at all timepoints (64 ± 3, 84 ± 4; 65 ± 5, LHL group; vs. 84 ± 3; 66 ± 2; 85 ± 5 mmHg, HLH group). At corresponding timepoints, hepatic venous saturation was 41 ± 15%; 58 ± 24%; 56 ± 21% in the LHL group vs. 50 ± 19%; 43 ± 20%; 41 ± 18% in the HLH group (P<0.05). No changes were observed in cardiac output, global or trans-splanchnic lactate levels and cytokine levels or in gastric tonometry CO2. CONCLUSION: Achieving a MAP target of 85 mmHg by means of norepinephrine infusion after CPB appears safe for the splanchnic circulation.

Missed carotid artery cannulation: a line crossed and lessons learnt.

We report a case of an infusion of intra-aortic propofol after the missed inadvertent placement of a central venous catheter into the right common carotid artery. Radiological imaging revealed bilateral ischaemic infarcts in the posterior fossa and right cerebral artery territories consistent with an embolic source. The potential causes of the neurological injuries sustained in this case are explored. Discussion focuses on the sequelae, management and prevention of an iatrogenic carotid artery injury from a central venous catheter insertion. Finally, we propose an algorithm for management of iatrogenic carotid artery cannulation.

Changing patterns in volatile anaesthetic agent consumption over seven years in Victorian public hospitals.

Evidence-based choices of volatile agents can increase health cost efficiencies. In this pharmaco-economic study, we evaluated the trends and costs of volatile agent use in Australian public hospitals. The total number of volatile agent (isoflurane, sevoflurane and desflurane) bottles ordered and inflation-adjusted costs were collected from 65 Victorian public hospitals from 2005 to 2011. Environmental costs were measured through the 100-year global warming potential index as carbon dioxide equivalents. During this time period, the aggregate inflation-adjusted expenditure was $39,209,878. Time series analysis showed that bottles of isoflurane ordered decreased by 419/year (99% confidence interval (CI): -603 to -235); costs decreased by $56,017/year (99% CI: -$93,243 to -$18,791). Bottles of sevoflurane increased by 1,330/year (99% CI: 1141 to 1,519); costs decreased by $423,3573/year (99% CI: -$720,030 to -112,783). Bottles of desflurane increased by 726/year (99% CI: 288 to 1,164); costs increased by $171,578/year (99% CI: $136,951 to $206,205). The amount of calculated greenhouse gas emissions released into the atmosphere over this period was 37,000 tonnes of carbon dioxide equivalents, with isoflurane contributing 6%, sevoflurane 17%, and desflurane 77% of this total. In conclusion, isoflurane is no longer being used in the majority of Victorian public hospitals, with sevoflurane and desflurane remaining as the primary volatile agents, utilised respectively at a ratio of 2.2 to 1, and costs at 0.8 to 1.

Pilot alternating treatment design study of the splanchnic metabolic effects of two mean arterial pressure targets during cardiopulmonary bypass.

BACKGROUND: The arterial pressure target for optimal splanchnic function during cardiopulmonary bypass (CPB) is uncertain. Thus, we aimed to compare the effects of two different arterial pressure targets during CPB on trans-splanchnic oxygenation, acid-base regulation, and splanchnic interleukin-6 (IL-6) and interleukin-10 (IL-10) flux. METHODS: Sixteen patients undergoing cardiac surgery with CPB in a university affiliated hospital were subjected to a prospective alternating treatment design interventional study. We measured arterial and hepatic vein blood gases, electrolytes, IL-6, and IL-10 while targeting a mean arterial pressure (MAP) of between 60 and 65 mm Hg for 30 min, a MAP of between 80 and 85 mm Hg for 30 min (using norepinephrine infusion), and finally 60-65 mm Hg MAP target for 30 min. RESULTS: The MAP targets were achieved in all patients [65 (4), 84 (4), and 64 (3) mm Hg, respectively; P<0.001] with a greater dose of norepinephrine infusion during the higher MAP target (P<0.001). With longer time on CPB, hepatic vein O2 saturation decreased, while magnesium, lactate, glucose, IL-6, and IL-10 increased independent of MAP target. The decrease in hepatic vein saturation was greater as the temperature increased (re-warming). Overall, there was trans-splanchnic oxygen, chloride, lactate, and IL-6 removal during CPB (P<0.001) and carbon dioxide, bicarbonate, glucose, and IL-10 release (P<0.001). Such removal or release was not affected by the MAP target. CONCLUSIONS: Targeting of a higher MAP during CPB by means of norepinephrine infusion did not affect splanchnic oxygenation, splanchnic acid-base regulation, or splanchnic IL-6 or IL-10 fluxes. Australian and New Zealand Clinical Trial Registry ACTRN 12611001107910.

Markers of coagulation activation after hepatic resection for cancer: evidence of sustained upregulation of coagulation.

We investigated the possibility that despite postoperative derangements of routine laboratory coagulation tests, markers of coagulation activation and thrombin generation would be normal or increased in patients undergoing hepatic resection for cancer In addition to the conventional coagulation tests prothrombin time and activated partial thromboplastin time, we measured select markers of coagulation activation prothrombin fragments 1 and 2 (PF1 + 2), thrombin-antithrombin complexes and plasma von Willebrand Factor antigen in 21 patients undergoing hepatic resection. The impact of hepatic resection on coagulation and fibrinolysis was studied with thromboelastography. Preoperatively, routine laboratory coagulation and liver function tests were normal in all patients. On the first postoperative day, prothrombin time was prolonged (range 16 to 22 seconds) in eight patients (38%). For these patients, thromboelastography was normal in six (75%), PF1 + 2 was elevated in four (50%), and thrombin-antithrombin complexes and von Willebrand Factor antigen were elevated in all, which was evidence of acute phase reaction, sustained coagulation factor turnover and activation. By the fifth postoperative day, despite normalisation of prothrombin time, markers of increased coagulation activity remained greater than 85% of baseline values. The findings indicate that in patients undergoing liver resection for cancer, there is significant and prolonged postoperative activation of the haemostatic system despite routine coagulation tests being normal or even prolonged. Before considering therapeutic interventions an integrated approach to interpreting haematological data with clinical correlation is essential.

Pharmacoeconomics of volatile inhalational anaesthetic agents: an 11-year retrospective analysis.

With continuously increasing expenditure on health care resources, various cost containment strategies have been suggested in regard to controlling the cost of inhalational anaesthetic agents. We performed a cost identification analysis assessing inhalational anaesthetic agent expenditure at a tertiary level hospital, along with an evaluation of strategies to contain the cost of these agents. The number of bottles of isoflurane, sevoflurane and desflurane used during the financial years 1997 to 2007 was retrospectively determined and the acquisition costs and cumulative drug expenditure calculated. Pharmacoeconomic modelling using low fresh gas flow anaesthesia was performed to evaluate practical methods of cost reduction. The use of isoflurane decreased from 384 bottles during 1997 to 204 in 2007. In contrast, use of sevoflurane increased from 226 bottles during 1998 to 875 during 2007. Desflurane use increased from 34 bottles per year during 2002 (its year of introduction) to 163 bottles per year in 2007. While the inflation-adjusted cumulative expenditure for these inhalational agents (Australian dollars) increased from $132,000 in 1997 to over $326,000 in 2007, an increase of 168%, patient workload over the same period increased by only 11%. Pharmacoeconomic modelling demonstrated that sevoflurane at 2 l/minute costs 19 times more than isoflurane at 0.5 l/minute. For the financial years 1997 to 2007, we found a progressive shift from the cheaper isoflurane to the more expensive agents, sevoflurane and desflurane, a shift associated with marked increases in costs. Low flow anaesthesia with isoflurane is one strategy to reduce costs.

Anaesthesia-related morbidity in Victoria: a report from 1990 to 2005.

This report involves a review of 736 cases of anaesthesia-related morbidity reported from 1990 to 2005 by the Victorian Consultative Council on Anaesthetic Mortality and Morbidity. Using a combination of an established classification system, emerging categorisation definitions and appropriate keywords, an analysis of the clinical issues and contributory factors was undertaken. Airway-related morbidity, respiratory complications and drug-related adverse events are the most commonly reported. Organisational issues are increasingly implicated in adverse anaesthesia outcomes.

Interpleural analgesia for attenuation of postoperative pain after hepatic resection.

SUMMARY: We performed a prospective randomised trial to evaluate the analgesic efficacy of interpleural analgesia in patients undergoing hepatic resection. The control group (n = 25) received multimodal analgesia with intravenous morphine patient-controlled analgesia; in addition, the interventional group (n = 25) received interpleural analgesia with a 20-ml loading dose of levo bupivacaine 0.5% followed by a continuous infusion of levobupivacaine 0.125%. Outcome measures included pain intensity on movement using a visual analogue scale over 24 h, cumulative morphine and rescue analgesia requirements, patient satisfaction, hospital stay and all adverse events. Patients in the interpleural group were less sedated and none required treatment for respiratory depression compared to 6 (24%) in the control group (p< 0.01). Patients in the interpleural group also had lower pain scores during movement in the first 24 h. Patients' satisfaction, opioid requirements and duration of hospital stay were similar. We conclude that continuous interpleural analgesia augments intravenous morphine analgesia, decreases postoperative sedation and reduces respiratory depression after hepatic resection.

Postoperative changes in prothrombin time following hepatic resection: implications for perioperative analgesia.

Disorders of coagulation may occur after uncomplicated hepatic resection in patients who have normal preoperative coagulation profiles and liver function tests. We present a retrospective study performed in a tertiary care university teaching hospital examining changes in liver function tests and coagulation profiles in patients undergoing hepatic resection. Data were obtained for 124 patients. When compared to the preoperative values, prothrombin times were significantly increased throughout the postoperative period. Prolongation of the prothrombin time was related to both duration of surgery and hepatic resection weight. There was no relationship between prothrombin time and patient age. Disorders of coagulation occur after hepatic resection even in patients who have normal preoperative coagulation and liver function tests. This has implications for anaesthetic practice, particularly when considering the use of an indwelling epidural catheter in patients undergoing hepatic resection.

The aetiology and pathogenesis of cardiopulmonary bypass-associated metabolic acidosis using polygeline pump prime.

OBJECTIVE: The pathogenesis of the metabolic acidosis of cardiopulmonary bypass (CPB) is not fully understood. New quantitative methods of acid-base balance now make it possible to describe it more clearly. Accordingly, we studied acid-base changes during CPB with polygeline pump prime and defined and quantified the factors which contribute to metabolic acidosis. DESIGN: Prospective cohort study. SETTING: Tertiary institution. PARTICIPANTS: 10 cardiac bypass graft surgery patients. INTERVENTIONS: Sampling of arterial blood at four time intervals: post-induction, on CPB during cooling and rewarming, and at skin closure. Measurement of serum Na+, K+, Mg++, Ca++, Cl-, bicarbonate, and phosphate concentrations, arterial blood gases, and serum albumin, lactate, and pyruvate concentrations at each collection point. Analysis of findings according to quantitative physicochemical principles, including calculation of the strong ion difference apparent, the strong ion difference effective, and the strong ion gap (SIG). MEASUREMENTS AND MAIN RESULTS: All patients developed a mild metabolic acidosis. The median serum standard bicarbonate concentration decreased from 25.0 mEq/l post-induction to 22.3 mEq/l at cooling and 22.2 mEq/l at rewarming (p < 0.05). The standard base excess decreased from a median of 1.55 mEq/l prior to CPB, to -2.50 mEq/l at cooling, -1.65 mEq/l at rewarming and, -0.85 mEq/l at skin closure (p < 0.001). This mild metabolic acidosis occurred despite a decrease in the median serum lactate concentration from 3.20 mEq/l post-induction to 1.83, 1.80, and 1.58 mEq/l at the three other time points. The increase in the median serum chloride concentration from 104.9 mEq/l post induction to 111.0, 111.1, and 110.0 mEq/l at the subsequent time points (p < 0.0001) was the main cause of the acidosis. There was also a significant increase in the SIG of 3.8 mEq/l at cooling and rewarming (p < 0.0001), suggesting a role for other unmeasured anions (polygeline) in the genesis of this acidosis. CONCLUSIONS: Using quantitative biophysical methods, it can be demonstrated that, in patients receiving a pump prime rich in chloride and polygeline, the metabolic acidosis of CPB is mostly due to iatrogenic increases in serum chloride concentration and unmeasured strong anions (SIG). Its development is partially attenuated by iatrogenic hypoalbuminaemia. Changes in lactate concentrations did not play a role in the development of metabolic acidosis in our patients.

Markers of splanchnic perfusion and intestinal translocation of endotoxins during cardiopulmonary bypass: effects of dopamine and milrinone.

OBJECTIVES: To investigate markers of splanchnic perfusion and the extent of endotoxemia during cardiopulmonary bypass (CPB) and to compare the effects of dopamine and milrinone on both splanchnic perfusion and endotoxemia. DESIGN: Prospective, randomized, blinded study. SETTING: University teaching hospital. PARTICIPANTS: Twenty-four patients scheduled for elective coronary artery bypass graft surgery (CABG). INTERVENTIONS: Patients were allocated to receive placebo (eight patients), dopamine (eight patients), or milrinone (eight patients) during CPB, and at seven times intraoperatively assays were performed of arterial and hepatic venous endotoxin levels, as well as measurements and/or calculations of intramucosal gastric pH (pHi), arterial and hepatic venous lactate-pyruvate ratio (lac/pyr), and hepatic venous oxygen saturation (S(HV)O2). MEASUREMENTS AND MAIN RESULTS: Both splanchnic and systemic endotoxin levels increased significantly, and this was unaffected by either dopamine or milrinone. Gastric pHi did not change, and there were only modest increases in lac/pyr, which remained within the normal range of less than 10 in both splanchnic and systemic blood. In the placebo group, S(HV)O2 decreased at the onset of CPB and also significantly decreased during rewarming and at the end of CPB and surgery. In the dopamine-treated patients, S(HV)O2 was greater compared with placebo and milrinone during both hypothermic and rewarming phases. CONCLUSION: Endotoxemia occurs during routine CPB. Neither pHi nor lac/pyr values showed adverse change, but hepatic venous oximetry may be a more sensitive indicator of splanchnic dysoxia in that S(HV)O2 was reduced during rewarming. Whether dopamine or milrinone confer protection against splanchnic ischemia remains uncertain.

Role of the splanchnic circulation in acid-base balance during cardiopulmonary bypass.

OBJECTIVE: The role of the splanchnic circulation in the development of the metabolic acidosis of cardiopulmonary bypass (CPB) is not fully understood. New quantitative methods of acid-base balance now offer the ability to define this phenomenon more accurately. Accordingly, we studied acid-base changes across the splanchnic circulation during CPB and defined and quantified the factors that contributed to acid-base balance. DESIGN: Prospective cohort study. SETTING: Tertiary institution. PATIENTS: Ten patients undergoing CPB for coronary artery bypass surgery. INTERVENTIONS: Sampling of arterial and hepatic venous blood at four time intervals: postinduction, on CPB during cooling and rewarming, and at skin closure. MEASUREMENTS: Measurement of serum Na+, K+, Mg++, Ca++, Cl-, HCO3-, and phosphate concentrations, arterial and hepatic venous blood gases and serum albumin, and lactate and pyruvate concentrations at each collection point. Analysis of findings according to quantitative physicochemical principles. MAIN RESULTS: All patients developed a mild metabolic acidosis with a decrease in median serum bicarbonate concentration from 24.97 mEq/L after induction to 22.29 mEq/L at cooling and 22.23 mEq/L at rewarming (p < .05). Before CPB, the pH decreased by 0.0275 (p < .05) across the splanchnic circulation, representing an increase of 2.26 nmol/L of hydrogen ions. Nevertheless, the splanchnic circulation induced a metabolic alkalosis, with a median transsplanchnic increase in the base excess of 1.50 mEq/L (p < .05). This change was largely due to a decrease in serum chloride and lactate concentration across the splanchnic circulation (p < .05). The acidifying effect of the splanchnic circulation was therefore the result of cell respiration with a median increase in carbon dioxide tension of 5.75 mm Hg (p < .05), causing the strong ion difference effective to increase by 1.94 mEq/L (p < .05). There were no other anions or acids added to the circulation by splanchnic organs (no change in strong ion gap). During and after CPB the splanchnic metabolic alkalinizing effect continued and the respiratory acidifying effect was reduced. This caused the splanchnic circulation to be pH neutral at these times. CONCLUSIONS: Using quantitative biophysical methods it can be demonstrated that the splanchnic circulation does not contribute to the metabolic acidosis of CPB, and that it continues to have a metabolic alkalinizing effect involving significant lactate extraction. However, its respiratory acidifying effect continues, although at a reduced rate.

Plasma bupivacaine levels after fascia iliaca compartment block with and without adrenaline.

Twenty children undergoing unilateral surgery on the thigh received a fascia iliaca compartment block using 2 mg.kg-1 of bupivacaine with (Group A) or without (Group P) adrenaline 1/200,000. Venous blood samples were taken as 5, 10, 15, 20, 25, 30, 40, 50 and 60 min after injection and assayed for concentrations of bupivacaine. In all subjects an adequate block was produced. Plasma concentrations of bupivacaine in Group P were significantly higher than those in Group A (P < 0.05). The median maximum plasma concentration (Cmax) was 1.1 micrograms.ml-1 (range 0.54-1.29 micrograms.ml-1) in Group P and 0.35 microgram.ml-1 (range 0.17-0.96 microgram.ml-1) in Group A. The median time taken to attain Cmax (Tmax) was 20 min (range 10-25 min) in Group P and 45 min (range 5-50 min) in Group A. The median time to first analgesia was 9.75 h (range 3-15 h) in Group P and 10.5 h (range 2.5-21 h) in Group A. The study confirmed the efficacy of the fascia iliaca compartment block in children and showed that when performed with 2 mg.kg-1 of bupivacaine it is associated with plasma concentrations of bupivacaine well within acceptable limits. The addition of adrenaline 1/200,000 to the local anaesthetic solution reduces the maximum plasma concentration reached.

Diclofenac vs oxybuprocaine eyedrops for analgesia in paediatric strabismus surgery.

Forty children undergoing strabismus surgery as day patients were randomly allocated to receive oxybuprocaine 0.4% eyedrops or 0.1% diclofenac eyedrops for perioperative analgesia. A non-invasive anaesthetic technique using the reinforced laryngeal mask airway was used. The study demonstrated that both topical analgesics provided good to excellent analgesia and the anaesthetic technique was associated with a relatively low incidence of nausea and vomiting. Complications were limited to two children who were admitted with persistent postoperative nausea and vomiting.

Diclofenac vs oxybuprocaine eyedrops for analgesia in paediatric strabismus surgery.

Forty children undergoing strabismus surgery as day patients were randomly allocated to receive oxybuprocaine 0.4% eyedrops or 0.1% diclofenac eyedrops for perioperative analgesia. A non-invasive anaesthetic technique using the reinforced laryngeal mask airway was used. The study demonstrated that both topical analgesics provided good to excellent analgesia and the anaesthetic technique was associated with a relatively low incidence of nausea and vomiting. Complications were limited to two children who were admitted with persistent postoperative nausea and vomiting.

Comparison of patient-controlled analgesia in children by i.v. and s.c. routes of administration.

Sixty children undergoing appendicectomy were allocated randomly to receive one of two PCA regimens with morphine. Group IV received standard i.v. PCA with a bolus dose of morphine 20 micrograms kg-1 and a background infusion of 4 micrograms kg-1 h-1 while group SC received PCA by the s.c. route with a bolus dose of morphine 20 micrograms kg-1 and a background infusion of 5 micrograms kg-1 h-1. In both groups there was a lockout interval of 5 min. Group SC self-administered significantly less morphine (P < 0.05) and had a significantly (P < 0.01) greater percentage of valid demands for analgesia than group IV. There were no differences in pain scores between the groups at rest or during movement. Group IV suffered significantly (P < 0.01) more hypoxic episodes than group SC. There were no differences between groups in the incidence of postoperative nausea and vomiting or oversedation. S.c. PCA appears to be as effective and safe as i.v. PCA. By giving patients feedback on the occurrence of valid demands for analgesia, s.c. PCA may produce more appropriate and effective use of PCA.