Biomedical subjects

C McCaul

Publications and source records attributed to C McCaul.

3 recordsLinked to original sources

PubMed2004

Effect of intraoperative intravenous crystalloid infusion on postoperative nausea and vomiting after gynaecological laparoscopy: comparison of 30 and 10 ml kg(-1).

BACKGROUND: I.V. fluid administration has been shown to reduce postoperative nausea and vomiting (PONV). The optimum dose is unknown. We tested the hypothesis that administration of i.v. crystalloid of 30 ml kg(-1) would reduce the incidence of PONV compared with 10 ml kg(-1) of the same fluid. METHODS: A total of 141 ASA I female patients undergoing elective gynaecological laparoscopy were randomized, in double-blind fashion, to receive either 10 ml kg(-1) (n=71; CSL-10 group) or 30 ml kg(-1) (n=70; CSL-30 group) of i.v. compound sodium lactate (CSL). RESULTS: In the first 48 h after anaesthesia, the incidence of vomiting was lower in the CSL-30 group than in the CSL-10 group (8.6% vs 25.7%, P=0.01). Anti-emetic use was less in the CSL-30 group at 0.5 h (2.9% vs 14.3%, P=0.04). The incidence of severe nausea was significantly reduced in the treatment group at awakening (2.9% vs 15.7%, P=0.02), 2 h (0.0% vs 8.6%, P=0.04) and cumulatively (5.7% vs 27.1%, P=0.001). The numbers needed to treat to prevent vomiting, severe nausea and antiemetic use in the first 48 h were 6, 5 and 6, respectively. CONCLUSION: I.V. administration of CSL 30 ml kg(-1) to healthy women undergoing day-case gynaecological laparoscopy reduced the incidence of vomiting, nausea and anti-emetic use when compared with CSL 10 ml kg(-1).

Adult↗

PubMed2002

Atracurium is associated with postoperative residual curarization.

BACKGROUND: Residual paralysis following the use of neuromuscular blocking drugs remains a clinical problem. As part of departmental quality assurance, we examined the degree of postoperative residual curarization (PORC) following atracurium. METHODS: Forty patients undergoing general anaesthesia involving atracurium were studied. Quantitative neuromuscular monitoring (mechanomyography, Myograph 2000, Biometer, Denmark) was performed by assessing the response to supramaximal train-of-four (TOF) stimulation of the ulnar nerve. Anaesthesia was provided by non-participating clinicians who were blinded to the study data. A TOF ratio </=0.7 at extubation was classified as PORC. RESULTS: At antagonism of neuromuscular block, 70% (28/40) of patients had a TOF ratio </=0.7, and 65% (26/40) of patients had a TOF ratio </=0.7 at extubation. Peripheral nerve stimulator use was associated with a longer interval from antagonism of block to extubation (P=0.01), but was not associated with differences in atracurium dosage or a reduction in PORC at extubation. Patients with TOF ratio </=0.7 at extubation had surgery of shorter duration [59 (SEM 6) vs 103 (9) min, P<0.001], greater doses of atracurium relative to the duration of surgery [6 (1) vs 11 (1) micro g kg(-1) min(-1), P<0.005], and shorter intervals from administration of last dose of atracurium to antagonism of neuromuscular block [29 (2) vs 53 (9) min, P<0.005] and from antagonism to extubation [6 (1) vs 15 (4) min, P<0.01]. Duration of surgical procedure was the sole multivariate predictor of PORC [odds ratio 0.94 (95% confidence intervals 0.91-0.98), P<0.01]. CONCLUSIONS: PORC remains a clinical problem despite use of intermediate-duration neuromuscular blocking drugs and peripheral nerve stimulators. Patients undergoing procedures of short duration may be at risk of inappropriately early tracheal extubation, possibly due to work pressures. The association between suboptimal antagonism of neuromuscular blockade and short procedures needs reinforcement during postgraduate training and departmental quality assurance.

Adult↗

PubMed1996

Upper oesophageal sphincter function during general anaesthesia.

The effect of anaesthesia on the upper oesophageal sphincter response to acid in the distal oesophagus and hypopharynx, and the effect of atracurium besylate on acid migration into the hypopharynx, was studied in 102 patients undergoing elective varicose vein surgery. Group 1 (n = 48) received a general anaesthetic and the muscle relaxant atracurium besylate whereas group 2 (n = 54) received a general anaesthetic without relaxation. Upper oesophageal sphincter tone was significantly lower in patients receiving muscle relaxants ('sphinctometer output', eight versus 14, P < 0.05). Sixteen patients (16 per cent) had reflux into the distal oesophagus during anaesthesia (nine in group 1 and seven in group 2, P not significant), of whom seven had reflux to the hypopharynx. There was no difference in incidence of hypopharyngeal acid exposure between groups. Upper oesophageal sphincter tone did not alter in response to reflux into the distal oesophagus or hypopharynx in either group. The upper oesophageal sphincter fails to protect the hypopharynx under general anaesthesia even if patients do not receive a muscle relaxant.

Adult↗