Search

Background: Dopamine is frequently used as inotropic agent in preterm infants. Its cardiovascular actions, as well as effects on neurovascular interactions may be neuroprotective during hypoxic-ischaemic events. Using a preterm lamb model we aimed to test the impact of intravenous dopamine on hypoxic-ischaemic brain injury. Method(s): Nine fetal lambs (91-93d gestation) were instrumented with catheters in carotid artery and jugular vein, and an umbilical cord occluder. Four days after surgery, intravenous dopamine (DA, 10 mug/kg/ min, n = 5) (or saline, n = 4) was commenced. Then a hypoxic-ischaemic insult was induced with umbilical cord occlusion for 25 min. Infusions were continued for another 72 h before euthanasia. Fetal brains were collected for immunohistopathology. Result(s): Dopamine infusion increased fetal heart rate (184 +/- 1 to 203 +/- 1 bpm, P < 0.05) while arterial pressure was unchanged. Three animals in the DA group showed tachycardic response to cord occlusion, while the other two animals showed bradycardic response similar to the saline group. In the periventricular white matter, the saline group had higher number of microglia (lectin positive) than the DA group (10 +/- 3 vs. 6 +/- 2 per 0.04 mm2, P < 0.05). The saline group tended to have shorter myelinated fibre lengths (CNPase) compared with the DA group (15.0 +/- 2.0 vs. 18.4 +/- 5.7 mum respectively, P = ns). No histological differences were evident between DA animals exhibiting a tachycardic or bradycardic response during cord occlusion. Conclusion(s): Intravenous dopamine reduces hypoxic-ischaemic white matter injury in preterm lambs, independent of the cardiovascular response during the hypoxic-ischaemia., F.Y. Wong, Ritchie Centre, MIMR, Monash University, Melbourne, VIC, Australia. E-mail: flora.wong@med.monash.edu.au, CONFERENCE ABSTRACT

Objective: Verapamil overdose can result in life-threatening shock, which may be exacerbated by refractory bradycardia and rate-dependent poor cardiac output. Emergency cardiac pacing has been rarely reported to effectively increase heart rate and blood pressure (BP). We report a case of electrical cardiac pacingresponsive hypotension in a mixed overdose. Case report: A 65-year-old female, with chronic obstructive pulmonary disease (COPD) and hypertension, presented 12 hours after overdose, including extended-release verapamil (7.2 g) and telmisartan-hydrochlorothiazide (1680/525 mg). She presented with pulse 30 bpm and systolic BP 80mmHg, peripherally vasodilated. Haemodynamic status deteriorated on arrival, with profound bradycardia (20/min) and episodes of pulseless electrical activity (PEA)-asystolic arrest requiring intermittent external cardiac massage. Resuscitation included endotracheal intubation, crystalloid resuscitation, atropine, calcium, glucagon, adrenaline, and isoprenaline boluses, vasoactive agents (adrenaline, noradrenaline, and isoprenaline) and high-dose insulin/euglycaemia. Bedside transthoracic echocardiogram demonstrated good cardiac contractility, suggesting peripheral vasodilation and heart rate-dependent hypotension. Bradycardia (20-30/min) with raterelated hypotension (80/35 mmHg) persisted despite pharmacotherapy. Transcutaneous cardiac pacing improved heart rate and BP (103/45mmHg) and a transvenous pacing wire was inserted with good capture. Mean arterial pressure was maintained >65 mmHg with paced-rate of 80/min and noradrenaline and vasopressin infusions. End organ perfusion also improved with cardiac pacing. BP fell when pacing rate was reduced. She recovered from her overdose, but died 9 days later from unrelated respiratory sepsis. Conclusion(s): There is limited literature on emergency cardiac pacing in the treatment of calcium-channel-blocker overdose-related hypotension or peri-arrest bradycardia [1]. In our case, significant h

Background: Along with catecholamine infusions, high-dose insulin euglycaemic therapy (HIET) is often used to treat beta blocker (BB) and calcium channel blocker (CCB) poisoning. Objective(s): Review clinical features and treatment of BB and CCB poi-soning in patients presenting to our toxicology service. Method(s): Retrospective, descriptive series of BB or CCB toxicity. Variables recorded include demographics, cardiovascular (CVS) drugs ingested, defined-daily-doses (DDD), vital signs, IV fluid, inotrope, and vasoactive agent doses. Result(s): Twenty-seven patients; 14 received HIET (BB in 70%, non-dihydropyridine-CCB 30%, deliberate-self-poisoning [DSP] 71%), 13 were treated with only catecholamines (BB 70%, non-dihydropyridine-CCB 30%, DSP 54%). The most frequently ingested BBs were metoprolol and atenolol. Multiple CVS drugs were ingested in 78% of cases. These included amlodipine, other vasodilators, and diuretics. There was no difference in mean age (HIET 61 years vs catecholamines 70 years). Patients receiving HIET were more commonly male (57 vs 15%, p = 0.04, OR 7.3, 95% CI 1.1-46) and ingested more than two defined-daily-doses of BB and/or non-dihydropyridine-CCB (71 vs 23%, p = 0.02, OR 8.3, 95% CI 1.4-47). Pre-treatment mean-SBP (HIET 78 mmHg vs catecholamines 76 mmHg) and median pulse (HIET 45 bpm vs catecholamines 55 bpm) were similar. The HIET group was more likely to receive multiple vasoactive therapies (100 vs 38%, p = 0.0006, OR 45, 95% CI 2.2-915) and catecholamines were commonly started before HIET. Mean time to initiation of HIET was 3.3 h; however, blood pressure improvement was often seen before this. Mean HIET infusion duration was 19.3 h. HIET patients had larger IV fluid volumes administered in the first 24 h (HIET mean 5.0 L vs catecholamines 3.1 L, p = 0.01). Mean time to stopping all IV-therapies was HIET 21 h vs catecholamines 17 h. Echocardiographic assessment occurred infrequently and mostly after catecholamines had been started. Con

Objective: Verapamil overdose can result in life-threatening shock, which may be exacerbated by refractory bradycardia and rate-dependent poor cardiac output. Emergency cardiac pacing has been rarely reported to effectively increase heart rate and blood pressure (BP). We report a case of electrical cardiac pacingresponsive hypotension in a mixed overdose. Case report: A 65-year-old female, with chronic obstructive pulmonary disease (COPD) and hypertension, presented 12 hours after overdose, including extended-release verapamil (7.2 g) and telmisartan-hydrochlorothiazide (1680/525 mg). She presented with pulse 30 bpm and systolic BP 80mmHg, peripherally vasodilated. Haemodynamic status deteriorated on arrival, with profound bradycardia (20/min) and episodes of pulseless electrical activity (PEA)-asystolic arrest requiring intermittent external cardiac massage. Resuscitation included endotracheal intubation, crystalloid resuscitation, atropine, calcium, glucagon, adrenaline, and isoprenaline boluses, vasoactive agents (adrenaline, noradrenaline, and isoprenaline) and high-dose insulin/euglycaemia. Bedside transthoracic echocardiogram demonstrated good cardiac contractility, suggesting peripheral vasodilation and heart rate-dependent hypotension. Bradycardia (20-30/min) with raterelated hypotension (80/35 mmHg) persisted despite pharmacotherapy. Transcutaneous cardiac pacing improved heart rate and BP (103/45mmHg) and a transvenous pacing wire was inserted with good capture. Mean arterial pressure was maintained >65 mmHg with paced-rate of 80/min and noradrenaline and vasopressin infusions. End organ perfusion also improved with cardiac pacing. BP fell when pacing rate was reduced. She recovered from her overdose, but died 9 days later from unrelated respiratory sepsis. Conclusion(s): There is limited literature on emergency cardiac pacing in the treatment of calcium-channel-blocker overdose-related hypotension or peri-arrest bradycardia [1]. In our case, significant h

Background: Along with catecholamine infusions, high-dose insulin euglycaemic therapy (HIET) is often used to treat beta blocker (BB) and calcium channel blocker (CCB) poisoning. Objective(s): Review clinical features and treatment of BB and CCB poi-soning in patients presenting to our toxicology service. Method(s): Retrospective, descriptive series of BB or CCB toxicity. Variables recorded include demographics, cardiovascular (CVS) drugs ingested, defined-daily-doses (DDD), vital signs, IV fluid, inotrope, and vasoactive agent doses. Result(s): Twenty-seven patients; 14 received HIET (BB in 70%, non-dihydropyridine-CCB 30%, deliberate-self-poisoning [DSP] 71%), 13 were treated with only catecholamines (BB 70%, non-dihydropyridine-CCB 30%, DSP 54%). The most frequently ingested BBs were metoprolol and atenolol. Multiple CVS drugs were ingested in 78% of cases. These included amlodipine, other vasodilators, and diuretics. There was no difference in mean age (HIET 61 years vs catecholamines 70 years). Patients receiving HIET were more commonly male (57 vs 15%, p = 0.04, OR 7.3, 95% CI 1.1-46) and ingested more than two defined-daily-doses of BB and/or non-dihydropyridine-CCB (71 vs 23%, p = 0.02, OR 8.3, 95% CI 1.4-47). Pre-treatment mean-SBP (HIET 78 mmHg vs catecholamines 76 mmHg) and median pulse (HIET 45 bpm vs catecholamines 55 bpm) were similar. The HIET group was more likely to receive multiple vasoactive therapies (100 vs 38%, p = 0.0006, OR 45, 95% CI 2.2-915) and catecholamines were commonly started before HIET. Mean time to initiation of HIET was 3.3 h; however, blood pressure improvement was often seen before this. Mean HIET infusion duration was 19.3 h. HIET patients had larger IV fluid volumes administered in the first 24 h (HIET mean 5.0 L vs catecholamines 3.1 L, p = 0.01). Mean time to stopping all IV-therapies was HIET 21 h vs catecholamines 17 h. Echocardiographic assessment occurred infrequently and mostly after catecholamines had been started. Con

We report a case of an infant with congenital diaphragmatic hernia (CDH) and hydrops fetalis who died from hypoxic respiratory failure. Autopsy revealed type B interrupted aortic arch (IAA). Microarray revealed a female karyotype with deletion of chromosome 1p21.1p12. There may be an association between 1p microdeletion, CDH, and IAA.Copyright © 2017 The Authors. Clinical Case Reports published by John Wiley & Sons Ltd.

We report a case of an infant with congenital diaphragmatic hernia (CDH) and hydrops fetalis who died from hypoxic respiratory failure. Autopsy revealed type B interrupted aortic arch (IAA). Microarray revealed a female karyotype with deletion of chromosome 1p21.1p12. There may be an association between 1p microdeletion, CDH, and IAA.Copyright © 2017 The Authors. Clinical Case Reports published by John Wiley & Sons Ltd.

A middle-aged man received a kidney transplant from a deceased multi-organ donor. The recipient suffered cardiac arrest several days post-operatively and sustained hypoxic brain injury and was declared brain dead. Following the family's consent, the allograft kidney was retrieved and re-transplanted into a man with end-stage renal failure secondary to reflux nephropathy. The liver was not transplanted due to suspicion of fatty changes based on macroscopic appearance. After transplantation of other organs, liver histology revealed coagulative parenchymal necrosis with nuclear inclusions and moderate parenchymal cholestasis, suggestive of herpes viral hepatitis. Renal implantation biopsy showed histiocytes with enlarged nuclei containing viral inclusions in the capsular fibrous tissue, with positive immunostaining for herpes simplex virus (HSV). Anti-viral therapy was commenced immediately after obtaining histological evidence of donor HSV infection. Our recipient had pre-formed immunoglobulin G antibodies to HSV-1 and HSV-2, and was immunoglobulin M negative pre-transplant. HSV viraemia was detected day 5 post-transplant with a viral load of 7688 copies/mL by polymerase chain reaction assay. The recipient completed a 30 day course of intravenous ganciclovir before switching to oral valganciclovir as standard cytomegalovirus prophylaxis. The HSV polymerase chain reaction became undetectable on day 7 of intravenous ganciclovir and has remained undetectable. The patient remains well 9 months post-transplant with an estimated glomerular filtration rate of 61 mL/min per 1.73 m2. Although renal allograft re-use has been shown to be technically possible with a good outcome in this recipient, this does raise issues including assessment of allografts that have undergone repeated severe ischaemic insults and the potential of transmission of infections.Copyright © 2015 Asian Pacific Society of Nephrology.

Background: The significance of pre-arrest factors in out-of-hospital cardiac arrests (OHCA) witnessed by emergency medical services (EMS) is not well established. The purpose of this study was to assess the association between prodromal symptoms and pre-arrest clinical observations on the arresting rhythm and survival in EMS witnessed OHCA. Method(s): Between 1st January 2003 and 31st December 2011, 1056 adult EMS witnessed arrests of a presumed cardiac aetiology were identified from the Victorian Ambulance Cardiac Arrest Registry. Pre-arrest prodromal features and clinical characteristics were extracted from the patient care record. Backward elimination logistic regression was used to identify pre-arrest factors associated with an initial shockable rhythm and survival to hospital discharge. Result(s): The median age was 73.0 years, 690 (65.3%) were male, and the rhythm of arrest was shockable in 465 (44.0%) cases. The most commonly reported prodromal symptoms prior to arrest were chest pain (48.8%), dyspnoea (41.8%) and altered consciousness (37.8%). An unrecordable systolic blood pressure was observed in 34.4%, a respiratory rate <13 or >24min-1 was present in 43.1%, and 45.5% had a Glasgow coma score <15. In the multivariable analysis, the following pre-arrest factors were significantly associated with survival: age, public location, aged care facility, chest pain, arm or shoulder pain, dyspnoea, dizziness, vomiting, ventricular tachycardia, pulse rate, systolic blood pressure, respiratory rate, Glasgow coma score, aspirin and inotrope administration. Conclusion(s): Pre-arrest factors are strongly associated with the arresting rhythm and survival following EMS witnessed OHCA. Potential opportunities to improve outcomes exist by way of early recognition and management of patients at risk of OHCA.Copyright © 2014.

A middle-aged man received a kidney transplant from a deceased multi-organ donor. The recipient suffered cardiac arrest several days post-operatively and sustained hypoxic brain injury and was declared brain dead. Following the family's consent, the allograft kidney was retrieved and re-transplanted into a man with end-stage renal failure secondary to reflux nephropathy. The liver was not transplanted due to suspicion of fatty changes based on macroscopic appearance. After transplantation of other organs, liver histology revealed coagulative parenchymal necrosis with nuclear inclusions and moderate parenchymal cholestasis, suggestive of herpes viral hepatitis. Renal implantation biopsy showed histiocytes with enlarged nuclei containing viral inclusions in the capsular fibrous tissue, with positive immunostaining for herpes simplex virus (HSV). Anti-viral therapy was commenced immediately after obtaining histological evidence of donor HSV infection. Our recipient had pre-formed immunoglobulin G antibodies to HSV-1 and HSV-2, and was immunoglobulin M negative pre-transplant. HSV viraemia was detected day 5 post-transplant with a viral load of 7688 copies/mL by polymerase chain reaction assay. The recipient completed a 30 day course of intravenous ganciclovir before switching to oral valganciclovir as standard cytomegalovirus prophylaxis. The HSV polymerase chain reaction became undetectable on day 7 of intravenous ganciclovir and has remained undetectable. The patient remains well 9 months post-transplant with an estimated glomerular filtration rate of 61 mL/min per 1.73 m2. Although renal allograft re-use has been shown to be technically possible with a good outcome in this recipient, this does raise issues including assessment of allografts that have undergone repeated severe ischaemic insults and the potential of transmission of infections.Copyright © 2015 Asian Pacific Society of Nephrology.

Background: The significance of pre-arrest factors in out-of-hospital cardiac arrests (OHCA) witnessed by emergency medical services (EMS) is not well established. The purpose of this study was to assess the association between prodromal symptoms and pre-arrest clinical observations on the arresting rhythm and survival in EMS witnessed OHCA. Method(s): Between 1st January 2003 and 31st December 2011, 1056 adult EMS witnessed arrests of a presumed cardiac aetiology were identified from the Victorian Ambulance Cardiac Arrest Registry. Pre-arrest prodromal features and clinical characteristics were extracted from the patient care record. Backward elimination logistic regression was used to identify pre-arrest factors associated with an initial shockable rhythm and survival to hospital discharge. Result(s): The median age was 73.0 years, 690 (65.3%) were male, and the rhythm of arrest was shockable in 465 (44.0%) cases. The most commonly reported prodromal symptoms prior to arrest were chest pain (48.8%), dyspnoea (41.8%) and altered consciousness (37.8%). An unrecordable systolic blood pressure was observed in 34.4%, a respiratory rate <13 or >24min-1 was present in 43.1%, and 45.5% had a Glasgow coma score <15. In the multivariable analysis, the following pre-arrest factors were significantly associated with survival: age, public location, aged care facility, chest pain, arm or shoulder pain, dyspnoea, dizziness, vomiting, ventricular tachycardia, pulse rate, systolic blood pressure, respiratory rate, Glasgow coma score, aspirin and inotrope administration. Conclusion(s): Pre-arrest factors are strongly associated with the arresting rhythm and survival following EMS witnessed OHCA. Potential opportunities to improve outcomes exist by way of early recognition and management of patients at risk of OHCA.Copyright © 2014.

Aim Congenital chylothorax is a rare but significant neonatal entity with major morbidity and mortality. The study aims to describe the related associations, management and outcomes of this condition in neonates. Methods This is a retrospective case series of all cases of congenital chylothorax admitted to a tertiary neonatal centre in the last 15 years. Results Ten cases of congenital chylothorax were identified. Eight infants were diagnosed antenatally and three infants had antenatal pleural drainage. Most infants were ventilated at birth and required immediate pleurocentesis. Post-natal management included drainage of fluid, ventilation, albumin replacement, octreotide and dietary modification with medium-chain triglyceride-enriched formula. Five infants had chromosomal aberrations identified, while a further two had dysmorphic features not substantiated with routine genetic testing. Noonan's syndrome was the single most common underlying genetic diagnosis. Associated anomalies and malformations were present in 80% of the cohort. There were two deaths in the series, both in infants with multiple co-morbidities. Conclusions Congenital chylothorax is a rare condition with overall prevalence of less than a case per year in our experience. Majority of infants had associated chromosomal anomalies and significant co-morbidities needing prolonged intensive care. © 2013 The Authors.

Aim Congenital chylothorax is a rare but significant neonatal entity with major morbidity and mortality. The study aims to describe the related associations, management and outcomes of this condition in neonates. Methods This is a retrospective case series of all cases of congenital chylothorax admitted to a tertiary neonatal centre in the last 15 years. Results Ten cases of congenital chylothorax were identified. Eight infants were diagnosed antenatally and three infants had antenatal pleural drainage. Most infants were ventilated at birth and required immediate pleurocentesis. Post-natal management included drainage of fluid, ventilation, albumin replacement, octreotide and dietary modification with medium-chain triglyceride-enriched formula. Five infants had chromosomal aberrations identified, while a further two had dysmorphic features not substantiated with routine genetic testing. Noonan's syndrome was the single most common underlying genetic diagnosis. Associated anomalies and malformations were present in 80% of the cohort. There were two deaths in the series, both in infants with multiple co-morbidities. Conclusions Congenital chylothorax is a rare condition with overall prevalence of less than a case per year in our experience. Majority of infants had associated chromosomal anomalies and significant co-morbidities needing prolonged intensive care. © 2013 The Authors.

Background: Speckle tracking echocardiography is increasingly being used to assess cardiac function in neonates. The objective was to compare speckle tracking strain indices between asphyxiated infants and healthy controls and to ascertain correlations between strain and 2D Doppler derived indices and cardiac troponin (biochemical marker of myocardial injury). Methods. Clinical and echocardiographic data from severely asphyxiated infants undergoing therapeutic hypothermia was evaluated retrospectively. This was compared with prospective data from healthy infants. Correlations between variables were assessed using Pearson's coefficient of correlation. Result(s): Twenty four infants with severe perinatal asphyxia were admitted during the study period of which 3 were not cooled and were excluded. The gestational age and birth weights of cases and controls were comparable. The mean left ventricular global longitudinal strain (GLS) from apical 4 chamber view was noted to be significantly impaired in the asphyxiated infants (- 11.01% +/- 2.48 vs - 21.45% +/- 2.74, p <0.001). Cardiac output was significantly lower in the asphyxiated infants (97 +/- 26 vs 230 +/- 60 ml/kg/min). In asphyxiated infants, GLS correlated positively with cardiac output (r2 = 0.86, p< 0.001) and negatively with serum troponin levels (r2 = 0.64, p< 0.001). GLS was less impaired in infants on inotropes compared to those not on inotropic support, -12.55% (1.9) vs -10.2% (1.3), p= 0.018. Infants who died had a lower global strain value compared to survivors, - 9.7% (1.6) vs - 12.8% (2.6), p = 0.02. Conclusion(s): 2D Speckle derived strain was impaired in asphyxiated infants. Significant correlations between GLS and cardiac output and troponin were noted. © 2013 Sehgal et al.; licensee BioMed Central Ltd.

Background: Speckle tracking echocardiography is increasingly being used to assess cardiac function in neonates. The objective was to compare speckle tracking strain indices between asphyxiated infants and healthy controls and to ascertain correlations between strain and 2D Doppler derived indices and cardiac troponin (biochemical marker of myocardial injury). Methods. Clinical and echocardiographic data from severely asphyxiated infants undergoing therapeutic hypothermia was evaluated retrospectively. This was compared with prospective data from healthy infants. Correlations between variables were assessed using Pearson's coefficient of correlation. Result(s): Twenty four infants with severe perinatal asphyxia were admitted during the study period of which 3 were not cooled and were excluded. The gestational age and birth weights of cases and controls were comparable. The mean left ventricular global longitudinal strain (GLS) from apical 4 chamber view was noted to be significantly impaired in the asphyxiated infants (- 11.01% +/- 2.48 vs - 21.45% +/- 2.74, p <0.001). Cardiac output was significantly lower in the asphyxiated infants (97 +/- 26 vs 230 +/- 60 ml/kg/min). In asphyxiated infants, GLS correlated positively with cardiac output (r2 = 0.86, p< 0.001) and negatively with serum troponin levels (r2 = 0.64, p< 0.001). GLS was less impaired in infants on inotropes compared to those not on inotropic support, -12.55% (1.9) vs -10.2% (1.3), p= 0.018. Infants who died had a lower global strain value compared to survivors, - 9.7% (1.6) vs - 12.8% (2.6), p = 0.02. Conclusion(s): 2D Speckle derived strain was impaired in asphyxiated infants. Significant correlations between GLS and cardiac output and troponin were noted. © 2013 Sehgal et al.; licensee BioMed Central Ltd.

Background: Dopamine is frequently used as inotropic agent in preterm infants. Its cardiovascular actions, as well as effects on neurovascular interactions may be neuroprotective during hypoxic-ischaemic events. Using a preterm lamb model we aimed to test the impact of intravenous dopamine on hypoxic-ischaemic brain injury. Method(s): Nine fetal lambs (91-93d gestation) were instrumented with catheters in carotid artery and jugular vein, and an umbilical cord occluder. Four days after surgery, intravenous dopamine (DA, 10 mug/kg/ min, n = 5) (or saline, n = 4) was commenced. Then a hypoxic-ischaemic insult was induced with umbilical cord occlusion for 25 min. Infusions were continued for another 72 h before euthanasia. Fetal brains were collected for immunohistopathology. Result(s): Dopamine infusion increased fetal heart rate (184 +/- 1 to 203 +/- 1 bpm, P < 0.05) while arterial pressure was unchanged. Three animals in the DA group showed tachycardic response to cord occlusion, while the other two animals showed bradycardic response similar to the saline group. In the periventricular white matter, the saline group had higher number of microglia (lectin positive) than the DA group (10 +/- 3 vs. 6 +/- 2 per 0.04 mm2, P < 0.05). The saline group tended to have shorter myelinated fibre lengths (CNPase) compared with the DA group (15.0 +/- 2.0 vs. 18.4 +/- 5.7 mum respectively, P = ns). No histological differences were evident between DA animals exhibiting a tachycardic or bradycardic response during cord occlusion. Conclusion(s): Intravenous dopamine reduces hypoxic-ischaemic white matter injury in preterm lambs, independent of the cardiovascular response during the hypoxic-ischaemia.

A young man with known steroid refractory terminal ileal Crohn's disease developed torrential gastrointestinal bleeding necessitating an emergency ileal resection. Serology was indicative of primary cytomegalovirus (CMV) infection and this was confirmed with histopathology of the resected ileum. We highlight the difficulty in clinical practice of distinguishing between CMV infection and CMV disease as well as the different investigations available to aid in the diagnosis of pathogenic CMV disease. © 2010 The Authors. Internal Medicine Journal © 2010 Royal Australasian College of Physicians.

Background: Dopamine is frequently used as inotropic agent in preterm infants. Its actions on alpha- and beta-adrenergic and dopaminergic receptors may possibly modify cardiovascular responses during hypoxic-ischaemic events. Using a preterm lamb model we aimed to test the impact of intravenous dopamine on cardiovascular parameters during hyoxicischaemia. Method(s): Six preterm fetal lambs (93 d gestation) were instrumented with catheters in carotid artery and jugular vein, and an inflatable umbilical cord occluder. Post-operatively continuous ECG and blood pressure were recorded, with daily arterial blood gases. After 4 days of recovery period, intravenous dopamine (or saline at same infusion rate) was commenced at 10 mug/kg/min. A hypoxic-ischaemic insult was induced with umbilical cord occlusion for 25 min. Dopamine was continued for another 72 hours before both ewe and foetus were euthanised. Result(s): Averaged baseline fetal heart rate (FHR) and mean arterial blood pressure (MAP) were similar between lambs given saline (control, 190 bpm and 38.7 mm Hg) and dopamine (DA, 196 bpm and 31.9 mm Hg), with no significant change after dopamine infusion was started. FHR of control group dropped significantly throughout cord occlusion to a nadir of 69.2 bpm and MAP dropped to nadir of 17.6 mm Hg (p < 0.001). In contrast, in DA group, FHR was elevated during cord occlusion to maximum of 260.3 bpm (p < 0.001), with no significant change in MAP. Conclusion(s): Intravenous dopamine modifies systemic cardiovascular response to severe hypoxic-ischaemia in preterm lambs. Whether other inotropic agents would have similar effects, and the corresponding impact on end organ injury remain to be clarified.

Study objective: To examine the effects of moderate hypothermia (33degreeC), induced by surface cooling in the ED and maintained for 12 hours in the ICU, on patients with anoxic brain injury after out-of-hospital cardiac arrest. Method(s): We conducted the study in a teaching hospital in Melbourne, Victoria, Australia. Participants were 22 adults who remained unconscious after return of spontaneous circulation following out-of-hospital cardiac arrest. This treatment group was studied prospectively, and a control group of 22 similar patients was studied by retrospective chart review. Moderate hypothermia (33degreeC) was induced in the ED by means of surface cooling and maintained for 12 hours in the ICU with rewarming to normothermia over 6 hours; control patients were maintained at normothermia. Result(s): There were no significant adverse effects of induced hypothermia. Cardiovascular changes included decreased pulse rate, but there were no significant differences in mean arterial blood pressure between the two groups. Small increases in serum potassium and decreases in pH at 18 hours in the hypothermic patients compared with normothermic controls were of no clinical significance. There were no septic complications. There was a significant increase in the number of patients with good outcome (Glasgow Outcome Coma Scale category 1 or 2) with induced hypothermia (11 of 22, versus 3 of 22 for normothermic controls; P<.05), and the mortality rate was significantly lower (10 of 22 versus 17 of 22; P<.05). Conclusion(s): Compared with historical normothermic controls, outcome was significantly improved and there was no increase in complications when moderate hypothermia was induced in comatose survivors of out-of- hospital cardiac arrest and maintained for 12 hours. Larger, prospective, randomized, controlled studies of induced moderate hypothermia in comatose survivors of out-of-hospital cardiac arrest are warranted.

Background: Monash Medical Centre (MMC) is a university-affiliated tertiary referral hospital in Melbourne, Victoria, Australia. The hospital has a large obstetric service and is the only quarternary obstetric unit in Victoria. The intensive care unit (ICU) is a busy 21-bed general unit with a broad casemix. While there is no designated state service obstetric ICU in Victoria, MMC ICU has increasingly tried to accept all obstetric patients referred, from both MMC and externally. Aim(s): To provide a local perspective on obstetric intensive care in Australia. Method(s): A retrospective audit of obstetric ICU admissions over 2 years. Result(s): Sixty women were admitted, of whom 46 were postpartum. Twenty-nine women were transferred from external sites. Mean maternal age was 30.7 years, mean gestational age 34.5 weeks and mean Acute Physiology and Chronic Health Evaluation (APACHE) version IIIj score 33. Obstetric haemorrhage was the most common admission diagnosis, followed by hypertensive spectrum disorders. Three women were admitted for induction of labour. Median length of stay was 35 h. Twenty-seven women (45%) required mechanical ventilation. No woman died in the ICU, although one died in hospital post-ICU discharge. No data were collected on neonatal outcomes. Conclusion(s): Critically ill obstetric patients can be managed successfully in a general ICU with obstetric input. It may be sensible to cluster these patients into units that are best equipped to deal with them, especially in the ante- and peripartum period. © 2011 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

Background: Dopamine is frequently used as inotropic agent in preterm infants. Its cardiovascular actions, as well as effects on neurovascular interactions may be neuroprotective during hypoxic-ischaemic events. Using a preterm lamb model we aimed to test the impact of intravenous dopamine on hypoxic-ischaemic brain injury. Method(s): Nine fetal lambs (91-93d gestation) were instrumented with catheters in carotid artery and jugular vein, and an umbilical cord occluder. Four days after surgery, intravenous dopamine (DA, 10 mug/kg/ min, n = 5) (or saline, n = 4) was commenced. Then a hypoxic-ischaemic insult was induced with umbilical cord occlusion for 25 min. Infusions were continued for another 72 h before euthanasia. Fetal brains were collected for immunohistopathology. Result(s): Dopamine infusion increased fetal heart rate (184 +/- 1 to 203 +/- 1 bpm, P < 0.05) while arterial pressure was unchanged. Three animals in the DA group showed tachycardic response to cord occlusion, while the other two animals showed bradycardic response similar to the saline group. In the periventricular white matter, the saline group had higher number of microglia (lectin positive) than the DA group (10 +/- 3 vs. 6 +/- 2 per 0.04 mm2, P < 0.05). The saline group tended to have shorter myelinated fibre lengths (CNPase) compared with the DA group (15.0 +/- 2.0 vs. 18.4 +/- 5.7 mum respectively, P = ns). No histological differences were evident between DA animals exhibiting a tachycardic or bradycardic response during cord occlusion. Conclusion(s): Intravenous dopamine reduces hypoxic-ischaemic white matter injury in preterm lambs, independent of the cardiovascular response during the hypoxic-ischaemia.

A young man with known steroid refractory terminal ileal Crohn's disease developed torrential gastrointestinal bleeding necessitating an emergency ileal resection. Serology was indicative of primary cytomegalovirus (CMV) infection and this was confirmed with histopathology of the resected ileum. We highlight the difficulty in clinical practice of distinguishing between CMV infection and CMV disease as well as the different investigations available to aid in the diagnosis of pathogenic CMV disease. © 2010 The Authors. Internal Medicine Journal © 2010 Royal Australasian College of Physicians.

Study objective: To examine the effects of moderate hypothermia (33degreeC), induced by surface cooling in the ED and maintained for 12 hours in the ICU, on patients with anoxic brain injury after out-of-hospital cardiac arrest. Method(s): We conducted the study in a teaching hospital in Melbourne, Victoria, Australia. Participants were 22 adults who remained unconscious after return of spontaneous circulation following out-of-hospital cardiac arrest. This treatment group was studied prospectively, and a control group of 22 similar patients was studied by retrospective chart review. Moderate hypothermia (33degreeC) was induced in the ED by means of surface cooling and maintained for 12 hours in the ICU with rewarming to normothermia over 6 hours; control patients were maintained at normothermia. Result(s): There were no significant adverse effects of induced hypothermia. Cardiovascular changes included decreased pulse rate, but there were no significant differences in mean arterial blood pressure between the two groups. Small increases in serum potassium and decreases in pH at 18 hours in the hypothermic patients compared with normothermic controls were of no clinical significance. There were no septic complications. There was a significant increase in the number of patients with good outcome (Glasgow Outcome Coma Scale category 1 or 2) with induced hypothermia (11 of 22, versus 3 of 22 for normothermic controls; P<.05), and the mortality rate was significantly lower (10 of 22 versus 17 of 22; P<.05). Conclusion(s): Compared with historical normothermic controls, outcome was significantly improved and there was no increase in complications when moderate hypothermia was induced in comatose survivors of out-of- hospital cardiac arrest and maintained for 12 hours. Larger, prospective, randomized, controlled studies of induced moderate hypothermia in comatose survivors of out-of-hospital cardiac arrest are warranted.

Background: Dopamine is frequently used as inotropic agent in preterm infants. Its actions on alpha- and beta-adrenergic and dopaminergic receptors may possibly modify cardiovascular responses during hypoxic-ischaemic events. Using a preterm lamb model we aimed to test the impact of intravenous dopamine on cardiovascular parameters during hyoxicischaemia. Method(s): Six preterm fetal lambs (93 d gestation) were instrumented with catheters in carotid artery and jugular vein, and an inflatable umbilical cord occluder. Post-operatively continuous ECG and blood pressure were recorded, with daily arterial blood gases. After 4 days of recovery period, intravenous dopamine (or saline at same infusion rate) was commenced at 10 mug/kg/min. A hypoxic-ischaemic insult was induced with umbilical cord occlusion for 25 min. Dopamine was continued for another 72 hours before both ewe and foetus were euthanised. Result(s): Averaged baseline fetal heart rate (FHR) and mean arterial blood pressure (MAP) were similar between lambs given saline (control, 190 bpm and 38.7 mm Hg) and dopamine (DA, 196 bpm and 31.9 mm Hg), with no significant change after dopamine infusion was started. FHR of control group dropped significantly throughout cord occlusion to a nadir of 69.2 bpm and MAP dropped to nadir of 17.6 mm Hg (p < 0.001). In contrast, in DA group, FHR was elevated during cord occlusion to maximum of 260.3 bpm (p < 0.001), with no significant change in MAP. Conclusion(s): Intravenous dopamine modifies systemic cardiovascular response to severe hypoxic-ischaemia in preterm lambs. Whether other inotropic agents would have similar effects, and the corresponding impact on end organ injury remain to be clarified.

Background: Monash Medical Centre (MMC) is a university-affiliated tertiary referral hospital in Melbourne, Victoria, Australia. The hospital has a large obstetric service and is the only quarternary obstetric unit in Victoria. The intensive care unit (ICU) is a busy 21-bed general unit with a broad casemix. While there is no designated state service obstetric ICU in Victoria, MMC ICU has increasingly tried to accept all obstetric patients referred, from both MMC and externally. Aim(s): To provide a local perspective on obstetric intensive care in Australia. Method(s): A retrospective audit of obstetric ICU admissions over 2 years. Result(s): Sixty women were admitted, of whom 46 were postpartum. Twenty-nine women were transferred from external sites. Mean maternal age was 30.7 years, mean gestational age 34.5 weeks and mean Acute Physiology and Chronic Health Evaluation (APACHE) version IIIj score 33. Obstetric haemorrhage was the most common admission diagnosis, followed by hypertensive spectrum disorders. Three women were admitted for induction of labour. Median length of stay was 35 h. Twenty-seven women (45%) required mechanical ventilation. No woman died in the ICU, although one died in hospital post-ICU discharge. No data were collected on neonatal outcomes. Conclusion(s): Critically ill obstetric patients can be managed successfully in a general ICU with obstetric input. It may be sensible to cluster these patients into units that are best equipped to deal with them, especially in the ante- and peripartum period. © 2011 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

Background: Cerebral blood flow (CBF)-metabolism coupling (FMC) is a fundamental regulatory mechanism of the mature brain, varying CBF to sustain cerebral metabolic rate of oxygen (CMRO2) and maintain cerebral oxygen extraction (OE). Previous studies suggest that FMC is immature in the preterm brain, predisposing to cerebral hypoxia. Dopamine is a natural neurotransmitter involved in mediating mature FMC, and is commonly used as inotropic agent in preterm infants. Using a lamb model we tested the impact of intravenous dopamine on FMC in the preterm brain, while manipulating CMRO2 using selective brain hypothermia. Method(s): Five preterm lambs (125-130 days gestation) were partially delivered by Caesarean section. Selective brain hypothermia was achieved by circulating ice-cold water in the pharynx with target brain temperature down to 25degreeC, measured by a fine thermistor placed beneath the dura. Cerebral arterial and venous oxygen saturations (CSaO2 and CSvO2) were analysed using blood samples from the carotid artery and superior sagittal sinus, and were used to estimate OE (OE=CSaO2-CSvO2,%). In three lambs, brain hypothermia was repeated with dopamine infusion at 20mcg/kg/min. Result(s): Mean brain temperature was reduced from 38.4 to 26.5degreeC, with no significant change in core temperature, heart rate and arterial blood pressure. Mean (SD) maximum change in OE during brain hypothermia was 11.4%, and reduced to -4.6% in lambs given dopamine infusion (P <= 0.05). Conclusion(s): Selective brain hypothermia uncouples CBF and cerebral metabolism, as indicated by increased cerebral oxygen extraction, without changes in systemic cardiovascular parameters. Dopamine infusion reduces the change in cerebral oxygen extraction during hypothermia, suggestive of an improvement in cerebral flow-metabolism coupling.

Background: Cerebral blood flow (CBF)-metabolism coupling (FMC) is a fundamental regulatory mechanism of the mature brain, varying CBF to sustain cerebral metabolic rate of oxygen (CMRO2) and maintain cerebral oxygen extraction (OE). Previous studies suggest that FMC is immature in the preterm brain, predisposing to cerebral hypoxia. Dopamine is a natural neurotransmitter involved in mediating mature FMC, and is commonly used as inotropic agent in preterm infants. Using a lamb model we tested the impact of intravenous dopamine on FMC in the preterm brain, while manipulating CMRO2 using selective brain hypothermia. Method(s): Five preterm lambs (125-130 days gestation) were partially delivered by Caesarean section. Selective brain hypothermia was achieved by circulating ice-cold water in the pharynx with target brain temperature down to 25degreeC, measured by a fine thermistor placed beneath the dura. Cerebral arterial and venous oxygen saturations (CSaO2 and CSvO2) were analysed using blood samples from the carotid artery and superior sagittal sinus, and were used to estimate OE (OE=CSaO2-CSvO2,%). In three lambs, brain hypothermia was repeated with dopamine infusion at 20mcg/kg/min. Result(s): Mean brain temperature was reduced from 38.4 to 26.5degreeC, with no significant change in core temperature, heart rate and arterial blood pressure. Mean (SD) maximum change in OE during brain hypothermia was 11.4%, and reduced to -4.6% in lambs given dopamine infusion (P <= 0.05). Conclusion(s): Selective brain hypothermia uncouples CBF and cerebral metabolism, as indicated by increased cerebral oxygen extraction, without changes in systemic cardiovascular parameters. Dopamine infusion reduces the change in cerebral oxygen extraction during hypothermia, suggestive of an improvement in cerebral flow-metabolism coupling.

The clinical heterogeneity of acute heart failure and the low number of controlled trials, to date, are the main causes of the lack of agreement on therapeutic objectives, uncertainty on the most appropriate management, and difficulties to obtain robust evidence for the treatment of this syndrome. The inappropriate use of inotropic agents is one the most common pitfalls shown by registries. Two to 10% of patients admitted for acute heart failure present with a low output syndrome, a clinical profile associated with high mortality, where inotropes may be a rational therapeutic choice. Crucial points for an effective use of inotropes are an accurate evaluation and selection of patients, tailoring of therapeutic schemes and strict patient monitoring. Beta-adrenergic agonists and phosphodiesterase inhibitors increase myocardial oxygen demand, favor arrhythmias and may cause peripheral vasodilation with a secondary decrease in coronary perfusion pressure. These effects may translate in myocardial ischemia, loss of cardiomyocytes and accelerated ventricular remodeling with worse prognosis. Levosimendan, a novel inotropic agent studied according to the principles of evidence-based medicine, augments myocardial contractility without changes in intracellular calcium concentrations, and with minimal impact on myocardial oxygen consumption. This paper, based on an expert consensus, aims to suggest criteria for the appropriate use of inotropic agents in acute heart failure, based on a critical appraisal of the existing evidence and clinical experience. © 2009 AIM Publishing Srl.