Peter Crichton Gordon

Intravenous Tramadol Versus Epidural Morphine for Postthoracotomy Pain Relief: A Placebo-controlled Double-blind Trial

Tramadol, an analgesic deriving only part of its effect via opioid agonist activity, might provide postoperative pain relief with minimal risk of respiratory depression.We, therefore, evaluated it for the control of postthoracotomy pain. In this randomized, double-blind study, a single intravenous (IV) bolus dose of 150 mg tramadol (Group T) was compared to epidural morphine administered as an initial 2-mg bolus and subsequent continuous infusion at a rate of 0.2 mg/h (Group M). Patients in each group could receive morphine IV from a patient-controlled analgesia (PCA) device. Pain scores, morphine consumption, arterial blood gases, and vital capacity values were recorded at regular intervals postoperatively until 8:00 AM on the first postoperative day. Both groups obtained adequate pain relief, and there were no between-group differences in pain scores or PCA morphine consumption. PaO2 was significantly higher in Group T at 2 h and PaCO2 significantly higher in Group M at 4 h postoperatively. There were no other significant respiratory differences. We conclude that a single dose of 150 mg tramadol given at the end of surgery provided postoperative analgesia equivalent to that provided by this dosage regimen of epidural morphine for the initial postoperative period. (Anesth Analg 1996;83:87-91)

Total intravenous anesthesia using propofol and alfentanil for coronary artery bypass surgery

Total intravenous anesthesia (TIVA) using alfentanil and propofol was used in 10 patients undergoing coronary artery bypass grafting. In an attempt to diminish unwanted side effects, lower doses were chosen than if either drug had been used alone. Anesthesia was induced with alfentanil, 75 micrograms/kg, followed by a sleep dose of propofol (mean dose 0.5 mg/kg). Maintenance in the precardiopulmonary bypass (CPB) period was achieved by infusions of propofol (6 mg/kg/h) and alfentanil (100 micrograms/kg/h). These were decreased by two thirds on commencement of CPB, and increased to half the initial rate on rewarming to 32 degrees C. Additional boluses of alfentanil were used to control breakthrough hypertension. The mean arterial pressure (MAP) and left ventricular stroke work index (LVSWI) fell significantly on induction. MAP but not LVSWI returned to baseline levels at skin incision. The cardiac index (CI) was maintained. A degree of myocardial depression was suggested by a fall in LVSWI despite maintaining preload, and by the failure of CI to increase in the presence of a reduced SVR. Anesthesia was satisfactory in all but one patient who developed breakthrough hypertension on sternotomy with transient ST segment depression, and awareness after CPB despite a plasma alfentanil concentration of 450 ng/mL. Mean time to wakening was 55 minutes. The study indicated that TIVA using propofol and alfentanil in the dosages described provides satisfactory basal anesthesia for coronary artery bypass surgery in patients with good left ventricular function, but requires additional pharmacologic manipulation, particularly with boluses of alfentanil, to control breakthrough hypertension.

The comparative effects of remifentanil or magnesium sulfate versus placebo on attenuating the hemodynamic responses after electroconvulsive therapy.

In this prospective, randomized, double-blind, placebo-controlled, crossover study we compared the effects of remifentanil or magnesium sulfate (MgSO4) versus placebo in attenuating the sympathetic response to electroconvulsive therapy. Twenty adults underwent a total of 115 anesthetics for therapeutic electroconvulsive therapy. Patients were randomly allocated twice into each of the three test groups: placebo control, MgSO4 30 mg/kg, or remifentanil 1.0 &mgr;g/kg. Systolic and diastolic arterial blood pressures, heart rate, and oxygen saturations were recorded before IV access was established. Anesthesia was induced with thiopental 4 mg/kg. The trial drug was then administered and neuromuscular blockade was followed with succinylcholine 0.5 mg/kg before electroconvulsive therapy was performed. All measurements were repeated at 0, 1, 3 and 10 min after the seizure ended. Remifentanil and MgSO4 produced a statistically significant attenuation of the increase in systolic arterial blood pressure at 0, 1, and 3 min (P < 0.05). Remifentanil, but not MgSO4 or placebo, attenuated the increase in heart rate at 1 and 3 min but not the peak rate. Remifentanil increased the duration of apnea (mean 90 s), with no other adverse respiratory effects. Mean seizure duration time was 33 (± 14) s, with no difference among the groups. In conclusion, remifentanil 1.0 &mgr;g/kg and MgSO4 30 mg/kg attenuated the systolic arterial blood pressure response to electroconvulsive therapy without reducing the duration of seizure activity. Because MgSO4 has less effect on HR, it might offer advantages over remifentanil in patients at risk for post-electroconvulsive therapy bradycardia.

Drug administration errors: time for national action

these include educating and raising awareness about medication safety, reading and re-reading labels on drug ampoules, checking the ampoule label with a second person or device (e.g. bar code reader), labelling all syringes in theatre, adhering to the international standard of colour-coded syringe labels, improving the organisation of drug drawers and work space, informing anaesthetists of new formulations or packaging of drugs, and establishing a mechanism for reporting and reviewing errors. In this issue of the SAMJ, Labuschagne et al. report on errors in drug administration by anaesthetists in public hospitals in the Free State province. 11 They confirm the problem of drug administration errors in anaesthesia, with nearly 40% of respondents admitting to making a drug administration error at some stage in their career. Their investigation, which polled full-time and occasional anaesthetic providers, supports the 90% incidence of responders reporting errors in previous South African surveys. 12,13 An expected finding in surveys of this nature is that a longer, full-time career in the specialty is more likely to be associated with a higher incidence of errors. This type of survey is useful to measure the occurrence of uncommon but potentially severe consequences, as it measures errors in very large numbers of cases, but lacks a denominator. 14

User applied drug labels in anaesthesia: time for action

In 1985 Professor Pat Foster from Tygerberg Hospital under the auspices of the SA Society of Anaesthesiologists (SASA) and South African Bureau of Standards (SABS) pioneered the development of a national standard of colour-coded syringe labels for anaesthetic drugs. This colour coding system has been modified and adopted by authorities in Australasia, Canada, the United Kingdom and the United States of America.

The amazing Minivent ventilator

In the mid-1960s Dr Anthony Cohen, an anaesthetist in private practice in Johannesburg, developed the Minivent respirator in response to the lack of ventilators that existed at that time in operating theatres in both private and state hospitals. The remarkable, rugged, miniature ventilator had only four components, could fit into an anaesthetist’s pocket and required no electrical power source. The pressure generated by the distension of a reservoir bag by the flow of anaesthetic gases to the patient triggered inspiration and the switch from inspiration to expiration was controlled by a pressure-sensitive magnetically operated bobbin. The device operated as a minute volume divider. Respiratory rate was obtained by counting the clicking noise from the bobbin and, provided there was no leak, tidal volume was easily calculated by dividing the gas flow by the respiratory rate. The device was widely used in numerous countries including South Africa, the United Kingdom, Australia and Canada.

Pioneers in South African Anaesthesia: Dr Heyman Harold (Heymie) Samson, anaesthetic innovator

Dr Heymie Samson (Figure 1) was born in Cape Town in 1911, matriculated at the South African College School in 1928, and studied medicine at London University. In 1938, he returned to general practice in Cape Town and married his wife, Phyllis. He volunteered for military service when war broke out in September 1939. He became the first South African to be awarded a Member of the Order of the British Empire (MBE) for gallantry in the North African Campaign. His interest in anaesthesia flourished during this period. He registered as a specialist anaesthetist in 1943, and in the same year while stationed at Voortrekkerhoogte became a founder member of the South African Society of Anaesthesiologists. After the war, he went into private practice in Johannesburg, while maintaining his academic link as an honorary member of the anaesthetic staff at the Johannesburg General Hospital until 1950. He returned to academic medicine as a part-time senior anaesthetist in the Johannesburg department in the early 1960s, a position which he held until 1980.

Pioneers in South African Anaesthesia: Thomas Voss and the “Elephant Tube”

Thomas James “Tom” Voss was born in Windhoek, Namibia, on 26 March 1926. He matriculated in South Africa from Pretoria Boys High School, and qualified with a Bachelor of Medicine, Bachelor of Surgery degree from the University of Cape Town (UCT) in 1950. After passing the Conjoint Diploma in Anaesthesia in London, he was appointed as a registrar in the Department of Anaesthesia at Groote Schuur Hospital in 1954. He was appointed as a specialist at Groote Schuur Hospital in 1958, and developed a special interest in the relatively new discipline of paediatric anaesthesia. In 1961, he became Head of Department at the Red Cross War Memorial Children’s Hospital, taking over from his mentor, Arthur Bull. In 1975, he was promoted ad hoc to Associate Professor at UCT.

Pioneers in South African Anaesthesia

Arthur Barclay Bull graduated MBChB at the University of Cape Town (UCT) in 1943. After internship at the New Somerset Hospital he joined the SA Medical Corps during the 2nd World War where be developed an interest in clinical anaesthesia. From 1948 – 1951 he underwent training as a registrar in anaesthesia at Groote Schuur Hospital. In 1953 he obtained the Diploma in Anaesthesia of the College of Physicians and Surgeons in Ireland and in 1960 became one of the 40 Foundation Fellows of the Anaesthetists of the Royal College of Surgeons in Ireland. From 1954-1955 he was appointed the Nuffield Dominion Clinical Assistant for South Africa in the Department of Anaesthesia at Oxford under Sir Robert Macintosh. In 1956 he was appointed Senior Anaesthetist at the newly opened Red Cross War Memorial Children’s Hospital. During that time he, together with Prof Pat Smythye, pioneered the use of prolonged curarisation and IPPV for treating tetanus. In 1960 he was awarded a WHO Travelling Fellowship and in 1977 an honorary fellowship from the Australian and New Zealand College of Anaesthetists. He succeeded Dr CS Jones as Head of the UCT Department in 1961, was appointed Associate Professor in 1963 and became the first holder of the UCT Chair of Anaesthetics in 1963. He served two terms as President of the SA Society of Anaesthetists and was Chairman of the SASA Committee that drew up the first Guidelines for Practice in 1987. He passed away in 2001aged 80 years.

The anaesthetist and the World Health Organization Surgical Safety Checklist

Correctly implemented, the World Health Organization Surgical Safety Checklist (WHO SSCL) may be a breakthrough in surgical patient care. The WHO SSCL was developed as part of the WHO’s World Alliance for Patient Safety Safe Surgery Saves Lives initiative. The project was led by Atul Gawande, a Boston-based endocrine surgeon, and developed over several months through discussions and meetings with surgeons, anaesthetists, operating nurses, and technical experts from around the world. It aims to reinforce accepted safety practices, and foster better communication and teamwork in theatres, thereby improving patient safety.