Efficacy of a novel prewarming system in the prevention of perioperative hypothermia. A prospective, randomized, multicenter study

BACKGROUND

Perioperative hypothermia is a common complication during general anesthesia. Although rewarming of patients before surgery has been used as a preventive measure and some guidelines recommend it, the implementation of prewarming for every surgical patient is cumbersome. Therefore, we sought to determine the efficacy of two novel prewarming methods that could facilitate prewarming in daily practice.

METHODS

This was a prospective, randomized, multi-center, controlled study. After IRB approval and informed consent, 90 patients undergoing surgery of 30-120 min duration with general anesthesia were randomly assigned to three groups: 1) standard preoperative insulation (Group A); 2) passive preoperative insulation with a commercial prewarming suit (Group B); 3) active preoperative prewarming with a forced-air warmer connected to a prewarming suit (Group C). All patients received warmed IV fluids and intraoperative forced air warming after induction of anesthesia. Oral temperatures were recorded in the preoperative and postoperative periods. Intraoperative core temperatures were measured with an esophageal probe.

RESULTS

Repeated-measures analysis of variance (ANOVA) and post hoc Scheffé's test identified a significantly higher core temperature in the actively prewarmed group (Group C) compared to both passive groups (A, B) at 15, 30, 45, 60, and 75 min (P<0.05) after induction of anesthesia and at the end of surgery. During the first 30 min after admission at PACU, also higher oral temperatures were measured in Group C, compared with both passive insulation groups.

CONCLUSION

In our study active prewarming with a forced-air warmer and an insulating prewarming suit achieves significantly higher core temperatures during anesthesia and at the end of surgery and avoids hypothermia at the end of surgery compared to commercial or conventional insulation techniques.

Prospective evaluation of intraoperative hemodynamics in liver transplantation with whole, partial and DCD grafts

The interaction of systemic hemodynamics with hepatic flows at the time of liver transplantation (LT) has not been studied in a prospective uniform way for different types of grafts. We prospectively evaluated intraoperative hemodynamics of 103 whole and partial LT. Liver graft hemodynamics were measured using the ultrasound transit time method to obtain portal (PVF) and arterial (HAF) hepatic flow. Measurements were recorded on the native liver, the portocaval shunt, following reperfusion and after biliary anastomosis. After LT HAF and PVF do not immediately return to normal values. Increased PVF was observed after graft implantation. Living donor LT showed the highest compliance to portal hyperperfusion. The amount of liver perfusion seemed to be related to the quality of the graft. A positive correlation for HAF, PVF and total hepatic blood flow with cardiac output was found (p = 0.001). Portal hypertension, macrosteatosis >30%, warm ischemia time and cardiac output, independently influence the hepatic flows. These results highlight the role of systemic hemodynamic management in LT to optimize hepatic perfusion, particularly in LDLT and split LT, where the highest flows were registered.

Semicontinuous intra-abdominal pressure measurement using an intragastric Compliance catheter

OBJECTIVE

To compare intra-abdominal pressure (IAP) measurements obtained from an intragastric Compliance catheter with the pressure measured directly in the abdominal cavity.

DESIGN AND SETTING

Prospective cohort study in an operating room of the Ghent University Hospital

PATIENTS

Seven patients undergoing elective laparoscopic cholecystectomy.

INTERVENTIONS

IAP was obtained from both an intragastric catheter and directly from the peritoneal cavity at 1-minute intervals in patients undergoing elective cholecystectomy and compared using Bland-Altman analysis.

MEASUREMENTS AND RESULTS

In 156 paired measurements obtained from 7 patients the mean difference between IAPgastric and IAPref was 0.12+/-0.70 mmHg (95% CI 0.01-0.23).

CONCLUSIONS

IAP measured using an intragastric Compliance catheter reliably reflects the reference IAP in patients undergoing laparoscopic cholecystectomy.

Glycopyrrolate during sevoflurane–remifentanil-based anaesthesia for cardiac catheterization of children with congenital heart disease

BACKGROUND

Remifentanil is recommended for use in procedures with painful intraoperative stimuli but minimal postoperative pain. However, bradycardia and hypotension are known side-effects. We evaluated haemodynamic effects of i.v. glycopyrrolate during remifentanil-sevoflurane anaesthesia for cardiac catheterization of children with congenital heart disease.

METHODS

Forty-five children undergoing general anaesthesia with remifentanil and sevoflurane were randomly allocated to receive either saline, glycopyrrolate 6 microg kg(-1) or glycopyrrolate 12 microg kg(-1). After induction of anaesthesia with sevoflurane, i.v. placebo or glycopyrrolate was administered. An infusion of remifentanil at the rate of 0.15 microg kg(-1) min(-1) was started, sevoflurane continued at 0.6 MAC and cisatracurium 0.2 mg kg(-1) was given. Heart rate (HR) and non-invasive arterial pressures were monitored and noted every minute for the first 10 min and then every 2.5 min for subsequent maximum of 45 min.

RESULTS

Baseline HR [mean (SD)] of 117 (20) beats min(-1) decreased significantly from 12.5 min onwards after starting the remifentanil infusion in the control group [106 (18) at 12.5 min and 99 (16) beats min(-1) at 45 min]. In the groups receiving glycopyrrolate, no significant decrease in HR was noticed. Glycopyrrolate at 12 microg kg(-1) induced tachycardia between 5 and 9 min after administration. Systolic and diastolic arterial pressures decreased gradually, but there were no significant differences in the pressures between groups.

CONCLUSION

I.V. glycopyrrolate 6 microg kg(-1) prevents bradycardia during general anaesthesia with remifentanil and sevoflurane for cardiac catheterization in children with congenital heart disease. Administering 12 microg kg(-1) of glycopyrrolate temporarily induces tachycardia and offers no additional advantage.

Estimation of myocardial performance in CABG patients

Myocardial performance index (MPI) permits a relative easy estimation of global left ventricular (LV) systolic and diastolic function. It was shown that MPI inversely correlated strongly with the maximum derivative of LV pressure with respect to time (+dP/dtmax). The current study evaluated the change of MPI during and immediately after coronary artery bypass surgery (CABG) surgery and analyzed the relationship between MPI and hydraulic energy (exemplified by preload adjusted maximal power-PAMP) during that same period. The study was conducted in 45 patients undergoing CABG. After induction of anaesthesia, 10 min after revascularization and 2 h postoperatively, haemodynamics were assessed. Preload was characterized by LV end-diastolic area indexed for BSA (LVEDAI); afterload was estimated by arterial elastance (Ea) and indexed systemic vascular resistance (SVRI). Global myocardial performance was indicated in terms of MPI and contractility was achieved by PAMP. Myocardial performance index increased postoperatively (0.44 +/- 0.13, 0.37 +/- 0.17 and 0.50 +/- 0.16, respectively; P < 0.001). Preload adjusted maximal power did not alter significantly (1.90 +/- 1.24, 2.02 +/- 1.34 and 2.12 +/- 1.00 W cm(-2)*10(4), respectively). Left ventricular enddiastolic area indexed did not change. Arterial elastance augmented to 0.76 +/- 0.39, 0.80 +/- 0.40 and 1.01 +/- 0.43 mmHg ml(-1), respectively; P < 0.001. Systemic vascular resistance did not change. A relationship was found between 1-MPI/LVEDAI2 and PAMP (R2 = 0.50). This study shows that in the setting of CABG surgery, MPI appears to be a good measure of global LV function.

Remifentanil infusion for cardiac catheterization in children with congenital heart disease

BACKGROUND

Cardiac catheterization of children with congenital heart disease is increasingly being performed under general anesthesia. Haemodynamic stability during anesthesia and fast and adequate recovery after the procedure is crucial in these patients. We performed a pilot study to evaluate hemodynamic stability when using remifentanil for anesthesia during cardiac catheterization. We also evaluated extubation times and recovery characteristics.

METHODS

In a randomized, prospective, double-blind study 30 children (aged 1.5-20 months) received a continuous infusion of either 0.2 (group 0.2) or 0.3 microg/kg/min remifentanil (group 0.3) as part of a balanced anesthesia with 0.6 MAC sevoflurane. Heart rate, noninvasive arterial blood pressure, end tidal CO2 and pulse oxymetry were monitored throughout the procedure. Extubation times were noted, and recovery from anesthesia was evaluated using Aldrete scores.

RESULTS

: Haemodynamic response to intubation was well blunted in both groups. No significant changes in hemodynamic variables were noted from induction of anesthesia until 10 min after intubation. From then on there was a decrease in HR and systolic arterial pressure, which remained significant throughout the procedure in both groups. Extubation times were similar in both groups: 7.3 min (2,1) in group 0.2 vs. 6.6 min (2,1) in group 0.3 (NS). The number of patients with an Aldrete score of nine or more was 14 (group 0.2) vs. 15 (group 0.3), 10 min after extubation (NS).

CONCLUSION

Both dose regimens of remifentanil provided stable hemodynamic conditions during anesthesia for cardiac catheterization of children with congenital heart disease and allowed for rapid and adequate recovery.

Steroid treatment in primary intracerebral haemorrhage

The efficiency of two types of steroid treatment was assessed in primary intracerebral haemorrhages. No significant difference in clinical evolution was observed between 57 cases treated with dexamethasone, 28 cases with methylprednisolone and 44 cases without corticosteroids. In a subgroup of 46 patients with putamino-capsular bleedings the non-steroid-treated group did significantly better than the steroid-treated one. Adverse reactions occurred at the same rate in the three groups.