The management of cardiac surgical patients in a general surgical recovery ward.

A suitable combination of anaesthetic and surgical techniques has allowed the safe management of post-operative cardiac surgical patients to be conducted in a surgical recovery area rather than in the intensive care ward. The results of the first 103 patients so managed (aged 49 +/- 10.7 years) are presented. Coronary artery bypass grafts were performed on 98 patients, 4 patients underwent repair of atrial septal defect and on 1 patient a pulmonary valvotomy was performed. The complications and their management are described.

Protamine sulphate and heparin rebound following open-heart surgery.

The efficacy of heparin reversal was investigated in 35 patients undergoing open-heart surgery. A total protamine sulphate dose of 3.0 mgs/kg was administered in divided doses and given as a continuous infusion. On this regime complete heparin neutralisation was observed 10 min after decannulation, but heparin levels were again detectable in 29% of cases 2 hours later. This phenomenon was found to correlate with the total circulating load of heparin to be neutralised. All cases with detectable postoperative heparin levels had in-vivo protamine sulphate: heparin ratios of less than 1.6. These data suggest that in-vitro assays of protamine sulphate neutralisation of heparin may seriously underestimate the required dose of protamine sulphate following open-heart surgery.

The role of anaesthetic management in enhancing peripheral blood flow in patients undergoing free flap transfer.

An anaesthetic protocol is described that is designed to promote peripheral blood flow and prevent vascular spasm in patients undergoing free flap transfer. The technique has been used successfully over a period of 3 years at St Thomas' Hospital, London, and since its introduction vascular spasm has ceased to be a major intraoperative problem.

Operating theatres. Cutting edge.

An enhanced postoperative theatre recovery unit can provide overnight intensive care for surgical patients. Most recovery units could be adapted for this purpose. Set-up capital costs are lower than for developing separate stand-alone facilities. 24-hour staffing is required for each OIR bed, although weekend cover can be downgraded to normal recover staffing, according to demand. Overnight intensive recovery and the ICU must collaborate in critical care provision.

Fast-tracking in cardiac surgery.

Fast-tracking in cardiac surgery evolved as the pressure on bed space in intensive therapy units (ITU) grew and clinical management improved. It relies on achieving a patient condition that allows for earlier extubation and postoperative management in alternative facilities to the ITU.

The effect of concentration on vasoactivity of bupivacaine and lignocaine.

In a double-blind trial bupivacaine 0.125, 0.25 and 0.5% and lignocaine 0.5, 1 and 2% were given intradermally to 31 volunteers. Vasoconstriction was observed more frequently at low concentrations of each drug, and vasodilatation at high concentrations. These observations were highly significant (P less than 0.001). Duration of action was unaffected by concentration, except in the case of bupivacaine 0.5%, the effect of which was longer lasting than that of other solutions.

An intradermal study of the local anaesthetic and vascular effects of the isomers of bupivacaine.

1 L(-)- and D(+)-bupivacaine in eight different concentrations from 0.06 to 7.69 mmol/l (0.002--0.25%) and physiological saline were given intradermally to seventeen volunteers, using a double-blind technique. 2 Local colour changes were observed as 'nil', 'pink' or 'pale' and analgesia to pinprick was assessed every 10 min to give an estimate of apparent in vivo potency and duration of action (50% recovery). 3 Both isomers were vasodilator in all cases at 7.69 mmol/l, but the incidence of vasodilatation waned with decreasing concentration, more rapidly with L(-)-than with D(+)-bupivacaine. 4 Only L(-)-bupivacaine showed a vasoconstrictor effect. This was maximal at a concentration of 0.48 mmol/l, when the incidence of pallor was 92%. 5 L(-)-bupivacaine had a longer duration of analgesic action than the (D+)-isomer from 0.48-3.84 mmol/l; this was reflected in a higher apparent in vivo potency.

Myasthenia gravis and cardiac surgery. A case report.

This paper describes the successful management of a diabetic patient with bulbar myasthenia who underwent mitral valve replacement and coronary revascularization.

Tension pneumothorax and pulse oximetry.

A case is described of spontaneous tension pneumothorax occurring during preparation for thoracic surgery. The earliest indication of this was unexplained haemoglobin desaturation as detected by pulse oximetry. This case report provides another example of the early warning potential of pulse oximetry.

Anaesthetic management and postoperative care of cardiac surgical patients in a general recovery ward.

The postoperative care of 143 cardiac surgical patients has been successfully conducted in a general surgical recovery ward. Admission was limited to overnight stay only and all but two patients were returned to the general ward the following day. There were no deaths. The intra-operative anaesthetic management was considered to have played an important part in the success of this technique.

Extracorporeal circuit sequestration of fentanyl and alfentanil.

Fentanyl or alfentanil, in doses approximating to those used in clinical practice, was added to the priming fluid of an extracorporeal circuit before the institution of cardiopulmonary bypass (CPB). The concentrations of both drugs in the priming fluid were measured over a 20-min period. The concentration of fentanyl decreased at neutral or high pH values, suggesting drug adsorption to the circuit. The concentration of alfentanil was unaffected. The administration of fentanyl to the priming fluid may produce lower anaesthetic concentrations than anticipated.

Hypotension following cimetidine administration during cardiopulmonary bypass.

Intravenous administration of cimetidine may occasionally cause profound hypotension. Cimetidine 200 mg was administered as a bolus injection to patients whilst on cardiopulmonary bypass and subsequent changes in systemic arterial pressure were recorded. A statistically significant fall in arterial pressure was observed (p less than 0.001), which was attributable to a fall in systemic vascular resistance.

Magnesium and coronary revascularization.

Twenty patients, who underwent coronary revascularization without cardioplegic arrest, were given (during cardiopulmonary bypass) either magnesium chloride 16 mmol in 10 ml of water (magnesium group) or 10 ml of water alone (control group). Plasma and urinary magnesium concentrations were measured for 24 h after operation. ECG was recorded continuously during this period. QT intervals corrected for heart rate (QTcorr) were calculated from periodic full lead ECG. The mean plasma magnesium concentrations in the control group were less than normal throughout the study, while hypomagnesaemia did not occur in the magnesium group. Urinary magnesium excretion was higher in the magnesium group, with 58% of the administered magnesium excreted in the first 24 h. The observed incidence of frequent or ventricular arrhythmias was 22% in the magnesium group compared with 63% in the control group. No significant differences in QTcorr intervals were observed between the groups.

Adult respiratory distress syndrome following closure of a chronic ventricular septal defect: possible relationship to the use of intracardiac gelatin-resorcin-formaldehyde glue.

Gelatin-resorcin-formaldehyde glue is now widely used in cardiac surgery, particularly in Europe. A case is reported where its use may have contributed to the pulmonary dysfunction seen postoperatively after elective closure of a postinfarct ventricular septal defect. It is believed that this is a result of a relatively high exposure of the pulmonary circulation to the glue, in particular to formalin. Although not proven, the authors advise caution when using the glue within the cardiac chambers.

Logical approach to lignocaine therapy.

Plasma lignocaine concentrations were measured during and after lignocaine infusions administered for suppressing ventricular dysrhythmias. Twenty-four patients with a primary diagnosis of acute myocardial infarction without gross circulatory disturbance received, after a bolus of lignocaine, either 4 mg/min for 30 minutes, 2 mg/min for two hours, then 1 mg/min thereafter or 1 mg/min throughout. The higher dose regimen produced continous therapeutic levels of lignocaine, which were achieved only after four hours by the lower dose. On the other hand, in patients who had undergone cardiac surgery and who had circulatory and heptic dysfunction the lower dose regimen achieved therapeutic levels early. The plasma half life was longer in the surgical group (P less than 0.02). The higher initial infusion rate is recommended for patients with acute myocardial infarction without gross circulatory impairment.

Postoperative cardiac surgical care: an alternative approach .

Combined appropriate anaesthetic and surgical techniques have allowed increasing numbers of patients to be successfully managed in a general surgical recovery ward after cardiac surgery rather than in an intensive care unit. From 1983 to 1989, 933 of 1542 patients undergoing open heart surgery were transferred to the general surgical recovery ward in the immediate postoperative period. Of these, 718 (77%) had undergone coronary artery bypass grafts, sometimes combined with other procedures and 168 (18%) had had cardiac valve replacements with or without other procedures. The remaining 47 (5%) had had miscellaneous cardiac operations. Significant cardiac complications occurred in 29 (3%) patients. The 24 hour chest radiograph was reported as abnormal (mainly atelectasis and effusion) in 63% of patients. Most resolved spontaneously or with physiotherapy. Twenty nine (3%) patients were re-explored to achieve haemostasis. There were no deaths in the general surgical recovery ward. Thirty seven (4%) patients had to be transferred to the intensive care unit for various reasons. The remaining 896 patients were transferred to the general ward after one night (871 patients) or two nights (25 patients) in the general surgical recovery ward. The average duration of stay in hospital for these patients was 9.3 days. Because of the overall success of such management and the low rate of complications over 80% of patients are now managed in the general surgical recovery ward after open heart surgery. The resulting savings in capital expenditure of equipment, medical, nursing, and technical personnel are substantial, and there are major implications for the planning of new cardiothoracic units.

Factors determining the duration of tracheal intubation in cardiac surgery: a single-centre sequential patient audit.

BACKGROUND AND OBJECTIVE: The study was designed to identify those factors associated with early tracheal extubation following cardiac surgery. Previous studies have tended to concentrate on surgery for coronary artery bypass or on other selected cohorts. METHODS: Sequential cohort analysis of 296 unselected adult cardiac surgery patients was performed over 3 months. RESULTS: In total, 39% of all patients were extubated within 6 h, 89% within 24 h and 95% within 48 h. Delayed extubation (>6 h after surgery) appeared unrelated to age, gender, body mass index, a previous pattern of angina or myocardial infarction, diabetes, preoperative atrial fibrillation, and preoperative cardiovascular assessment, as well as other factors. Delayed tracheal extubation was associated with poor left ventricular, renal and pulmonary function, a high Euroscore, as well as the type, duration and urgency of surgery. Early extubation (<6 h) was not associated with a reduced length of stay in either the intensive care unit or in hospital compared with patients who were extubated between 6 and 24 h. In these groups, it is presumed that organizational and not clinical factors appear to be responsible for a delay in discharge from intensive care. Patients who were extubated after 24 h had a longer duration of hospital stay and a greater incidence of postoperative complications. Postoperative complications were not adversely affected by early tracheal extubation. CONCLUSIONS: In an unselected sequential cohort, both patient- and surgery-specific factors may be influential in determining the duration of postoperative ventilation of the lungs following cardiac surgery. In view of the changing nature of the surgical population, regular re-evaluation is useful in reassessing performance.