Serious adverse events attributed to remifentanil patient-controlled analgesia during labour in The Netherlands.

BACKGROUND: During labour, remifentanil patient-controlled analgesia is used as an alternative to neuraxial analgesia. Remifentanil is associated with hypoventilation and respiratory depression but the frequency of serious maternal and neonatal adverse events is unknown. The aim of this study was to estimate the number of serious adverse events attributed to the use of remifentanil patient-controlled analgesia during labour in The Netherlands and to investigate the circumstances (e.g. monitoring, practice deviations) of these events and the subsequent management. METHODS: In a nationwide survey among obstetricians, anaesthetists and clinical midwives the frequency of serious adverse events was assessed. A questionnaire was sent by email to all 61 Dutch hospitals in which remifentanil patient-controlled analgesia is, or has been, available for labour analgesia. All reported cases were assessed independently by two expert teams. RESULTS: We received information from all hospitals. After independent assessments, 17 cases of single maternal desaturation; 10 maternal cases of apnoea, bradycardia and/or cardiac arrest; and two neonatal cases of respiratory depression, over a period of more than 10 years of remifentanil patient-controlled analgesia use, were identified as a serious adverse event. All serious adverse events were resolved without irreversible damage. CONCLUSIONS: The risk of a potentially life-threatening serious adverse event attributed to remifentanil patient-controlled analgesia seems to be low. All patients recovered without deficit. Adherence to strict monitoring and the attendance of trained healthcare providers is required to safely use remifentanil for labour analgesia.

Transcranial Doppler monitoring during carotid endarterectomy helps to identify patients at risk of postoperative hyperperfusion.

OBJECTIVES: to investigate whether transcranial Doppler (TCD) monitoring can identify patients at risk of hyperperfusion, and whether active postoperative treatment of selected patients decreases the risk of intracerebral haemorrhage (ICH). DESIGN: a case cohort study of 688 patients undergoing carotid endarterectomy (CEA) with intraoperative TCD monitoring. METHODS: sixty-two patients (9%) fulfilled the TCD criteria for hyperperfusion, i.e. >100% increase of peak blood flow velocity or pulsatility index of the middle cerebral artery, compared to preclamp baseline values. In these patients, blood pressure was closely monitored and controlled postoperatively. RESULTS: postoperatively, seven of these patients (11%) exhibited clinical signs or symptoms of hyperperfusion but no cerebral haemorrhage (ICH). This is a significantly better outcome (p <0.005) compared to a 2% incidence of ICH after CEA in previous years in our hospital. CONCLUSIONS: patients at risk of hyperperfusion syndrome after CEA can be identified intraoperatively by TCD monitoring. In these selected patients, immediate and adequate postoperative treatment of hypertension results in a decreased risk of intracerebral haemorrhage.

Increased oxygen consumption after cardiac surgery is associated with the inflammatory response to endotoxemia.

OBJECTIVE: The aim of this study was to determine whether the increase in post-operative oxygen consumption (delta VO2) in cardiac surgery patients is related to endotoxemia and subsequent cytokine release and whether delta VO2 can be used as a parameter of post-perfusion syndrome. DESIGN: Prospective study. SETTING: Operating room and intensive care unit of a university hospital. PATIENTS: Twenty-one consecutive male patients undergoing elective coronary artery bypass surgery without major organ dysfunction and not receiving corticosteroids. MEASUREMENTS AND RESULTS: Plasma levels of endotoxin, tumor necrosis factor (TNF) and interleukin-6 (IL-6) were measured before, during and for 18 h after cardiac surgery. Oxygen consumption, haemodynamics, the use of IV fluids and dopamine, body temperature and the time of extubation were also measured. Measurements from patients with high delta VO2 (> or = median value of the entire group) were compared with measurements from patients with low delta VO2 (< median). Patients with high delta VO2 had higher levels of circulating endotoxin (P = 0.004), TNF (P = 0.04) and IL-6 (P = 0.009) received more IV fluids and dopamine while in the ICU, and were extubated later than patients with low delta VO2. Several hours after delta VO2 the patient's body temperature rose. Forward stepwise regression analysis showed that circulating endotoxin and TNF explained 50% of the variability of delta VO2. CONCLUSIONS: This study demonstrates that patients with high post operative oxygen consumption after elective cardiac surgery have higher circulating levels of endotoxin, TNF and IL-6 and also have more symptoms of post-perfusion syndrome. Early detection of high VO2 might be used as a clinical signal to improve circulation in order to meet the high oxygen demand of inflammation. In addition, continuous measurement of VO2 provides us with a clinical parameter of inflammation in interventional studies aiming at a reduction of endotoxemia or circulating cytokines.