National priorities for perioperative research in South Africa.

BACKGROUND: Perioperative research is currently unco-ordinated in South Africa (SA), with no clear research agenda. OBJECTIVE: To determine the top ten national research priorities for perioperative research in SA. METHODS: A Delphi technique was used to establish consensus on the top ten research priorities. RESULTS: The top ten research priorities were as follows: (i) establishment of a national database of (a) critical care outcomes, and (b) critical care resources; (ii) a randomised controlled trial of preoperative B-type natriuretic peptide-guided medical therapy to decrease major adverse cardiac events following non-cardiac surgery; (iii) a national prospective observational study of the outcomes associated with paediatric surgical cases; (iv) a national observational study of maternal and fetal outcomes following operative delivery in SA; (v) a stepped-wedge trial of an enhanced recovery after surgery programme for (a) surgery, (b) obstetrics, (c) emergency surgery, and (d) trauma surgery; (vi) a stepped-wedge trial of a surgical safety checklist on patient outcomes in SA; (vii) a prospective observational study of perioperative outcomes after surgery in district general hospitals in SA; (viii) short-course interventions to improve anaesthetic skills in rural doctors; (ix) studies of the efficacy of simulation training to improve (a) patient outcomes, (b) team dynamics, and (c) leadership; and (x) development and validation of a risk stratification tool for SA surgery based on the South African Surgical Outcomes Study (SASOS) data. CONCLUSIONS: These research priorities provide the structure for an intermediate-term research agenda.

Anaesthesia - what has the University of Cape Town contributed?

From humble beginnings, the University of Cape Town's Department of Anaesthesia has played a major role in the development of anaesthesia as a speciality, in South Africa and internationally. We highlight these contributions in clinical service, teaching and research, with particular emphasis on the department's leading role in the evolution of anaesthetic safety in adults and children: from the development of the treatment of malignant hyperthermia, to unique studies in mortality associated with anaesthesia, and modern contributions to improved drug safety. Innovations in anaesthetic techniques have contributed to significant surgical developments, including the first heart transplant. Furthermore, our research has contributed to major advances in obstetric and endocrine anaesthesia, and training in the department is recognised as being among the best in the world.

Obstetric anaesthesia in low-resource settings.

Close co-operation between obstetricians and obstetric anaesthesia providers is crucial for the safety and comfort of parturients, particularly in low-resource environments. Maternal and foetal mortality is unacceptably high, and the practice of obstetric anaesthesia has an important influence on outcome. Well-conducted national audits have identified the contributing factors to anaesthesia-related deaths. Spinal anaesthesia for caesarean section is the method of choice in the absence of contraindications, but is associated with significant morbidity and mortality. Minimum requirements for safe practice are adequate skills, anaesthesia monitors, disposables and drugs and relevant management protocols for each level of care. The importance of current outreach initiatives is emphasised, and educational resources and the available financial sources discussed. The difficulties of efficient procurement of equipment and drugs are outlined. Guiding principles for the practice of analgesia for labour, anaesthesia for caesarean section and the management of obstetric emergencies, where the anaesthetist also has a central role, are suggested.

Hemodynamic effects of ephedrine, phenylephrine, and the coadministration of phenylephrine with oxytocin during spinal anesthesia for elective cesarean delivery.

BACKGROUND: Hemodynamic responses to vasopressors used during spinal anesthesia for elective Cesarean delivery, have not been well described. This study compared the effects of bolus phenylephrine and ephedrine on maternal cardiac output (CO). The hypothesis was that phenylephrine, but not ephedrine, decreases CO when administered in response to hypotension during spinal anesthesia. METHODS: Forty-three patients were randomized to receive 80 microg of phenylephrine or 10 mg of ephedrine. Both pulse wave form analysis and transthoracic bioimpedance changes were used to estimate stroke volume in each patient. Hemodynamic responses to spinal anesthesia and oxytocin were also recorded. A subgroup of 20 patients was randomized to receive oxytocin compared with oxytocin plus 80 microg of phenylephrine after delivery. RESULTS: Mean CO and maximum absolute response in CO were significantly lower during the 150 s after phenylephrine administration than after ephedrine (6.2 vs. 8.1 l/min, P = 0.001, and 5.2 vs. 9.0 l/min, P < 0.0001, respectively for pulse wave form analysis, and 5.2 vs. 6.3 l/min, P = 0.01 and 4.5 vs. 6.7 l/min, P = 0.0001, respectively for bioimpedance changes). CO changes correlated with heart rate changes. Coadministration of phenylephrine obtunded oxytocin-induced decreases in systemic vascular resistance and increases in heart rate and CO. Trends in CO change were similar using either monitor. CONCLUSIONS: Bolus phenylephrine reduced maternal CO, and decreased CO when compared with ephedrine during elective spinal anesthesia for Cesarean delivery. CO changes correlated with heart rate changes after vasopressor administration, emphasizing the importance of heart rate as a surrogate indicator of CO. Coadministered phenylephrine obtunded hemodynamic responses to oxytocin.

Hemodynamic changes associated with spinal anesthesia for cesarean delivery in severe preeclampsia.

BACKGROUND: Hemodynamic responses to spinal anesthesia (SA) for cesarean delivery in patients with severe preeclampsia are poorly understood. This study used a beat-by-beat monitor of cardiac output (CO) to characterize the response to SA. The hypothesis was that CO would decrease from baseline values by less than 20%. METHODS: Fifteen patients with severe preeclampsia consented to an observational study. The monitor employed used pulse wave form analysis to estimate nominal stroke volume. Calibration was by lithium dilution. CO and systemic vascular resistance were derived from the measured stroke volume, heart rate, and mean arterial pressure. In addition, the hemodynamic effects of phenylephrine, the response to delivery and oxytocin, and hemodynamics during recovery from SA were recorded. Hemodynamic values were averaged for defined time intervals before, during, and after SA. RESULTS: Cardiac output remained stable from induction of SA until the time of request for analgesia. Mean arterial pressure and systemic vascular resistance decreased significantly from the time of adoption of the supine position until the end of surgery. After oxytocin administration, systemic vascular resistance decreased and heart rate and CO increased. Phenylephrine, 50 mug, increased mean arterial pressure to above target values and did not significantly change CO. At the time of recovery from SA, there were no clinically relevant changes from baseline hemodynamic values. CONCLUSIONS: Spinal anesthesia in severe preeclampsia was associated with clinically insignificant changes in CO. Phenylephrine restored mean arterial pressure but did not increase maternal CO. Oxytocin caused transient marked hypotension, tachycardia, and increases in CO.

The role of the anaesthetist in the management of the pre-eclamptic patient.

PURPOSE OF REVIEW: Recent literature on the anaesthetist's role in the management of the patient with severe pre-eclampsia is reviewed, with particular emphasis on the role of regional anaesthesia. RECENT FINDINGS: Laboratory findings in pre-eclamptic women include increased levels of markers of oxidative stress and circulating tyrosine kinase 1, and inflammatory activation of leucocytes. Magnesium sulphate is the most effective agent for seizure prophylaxis. The optimal pharmacological agents for acute control of blood pressure remain controversial. The benefits of epidural analgesia in labour are well established. Single-shot spinal anaesthesia for caesarean section is safe in the absence of contraindications. Successful use of combined spinal-epidural anaesthesia has been described. Most studies on maternal haemodynamics have employed heart rate and blood pressure data as surrogate measures of cardiac output. Noninvasive cardiac output studies provide further insight into the haemodynamic response during neuraxial techniques for caesarean section. SUMMARY: The value of regional anaesthesia cannot be over-emphasized. Recent research into spinal anaesthesia for caesarean section suggests a lower susceptibility to hypotension and probably less impairment of cardiac output than in healthy parturients. Noninvasive cardiac output measurement may also have advantages in critical care management.

Secondary injury in traumatic brain injury patients--a prospective study.

OBJECTIVE: Secondary insults of hypotension and hypoxia significantly impact on outcome in patients with traumatic brain injury (TBI). More than 4 hours' delay in evacuation of intracranial haematomas has been demonstrated to have an additional impact on outcome. The objective of this study was to document the incidence of these preventable secondary insults in patients admitted with moderate or severe brain injury. METHODOLOGY: All moderate and severe head injury patients admitted to Groote Schuur Hospital over a 3-month period were studied prospectively. Data were obtained from ambulance dockets, referral letters, patient charts and attending medical staff. Preventable secondary insults (hypotension, hypoxia) and time delay to assessment and surgery were documented. Outcome was assessed using the Glasgow outcome scale (GOS) at discharge or outpatient follow-up. RESULTS: Ninety-six patients were studied. Forty-nine patients experienced at least one recorded preventable event of hypoxia or hypotension. Seventeen had an intracranial haematoma requiring evacuation. The mean time interval between injury and surgery was 455 minutes. No haematoma was evacuated within 4 hours of injury. Patients referred via a primary or secondary care facility experienced a mean additional delay of 70 minutes. These results demonstrated a significant incidence of secondary injury and delay to assessment and surgery. We believe that education and a raised awareness of the impact of secondary insults may have a positive impact on TBI outcome in our referral area.