Yoshiaki Terao

Quantitative analysis of the relationship between sedation and resting energy expenditure in postoperative patients.

ObjectiveTo analyze quantitatively the relationship between sedation and resting energy expenditure or oxygen consumption in postoperative patients. DesignA prospective, clinical study. SettingAn eight-bed intensive care unit at a university hospital. PatientsThirty-two postoperative patients undergoing either esophagectomy or surgery of malignant tumors of the head and neck who required mechanical ventilation and sedation for ≥2 days postoperatively. InterventionsNone. Measurements and Main ResultsA total of 133 metabolic measurements were performed. Ramsay sedation scale (RSS), body temperature, and the dose of midazolam were evaluated at the time of the metabolic cart study. All patients received analgesia with buprenorphine at a fixed dose of 0.625 &mgr;g·kg−1·hr−1 continuously. Midazolam was used for induction and maintenance of intravenous sedation after admission to the intensive care unit. The initial dose was 0.04 mg·kg−1·hr−1 and was adjusted to achieve a desired depth of sedation at 3, 4, or 5 on the RSS every 4 hrs. The degree of sedation was classified into three states: light sedation (RSS 2–3; n = 49), moderate sedation (RSS 4; n = 39), and heavy sedation (RSS 5–6; n = 45). ResultsWith increasing the depth of sedation, oxygen consumption index (mL·min−1·m−2), resting energy expenditure index (REEI; kcal·day−1·m−2), and REE/basal energy expenditure (BEE) decreased significantly. Oxygen consumption index (mean ± sd), REEI, and REE/BEE were 151 ± 18, 1032 ± 120, and 1.29 ± 0.17 in the light sedation, 139 ± 22, 947 ± 143, and 1.20 ± 0.16 in the moderate sedation, and 125 ± 16, 865 ± 105, and 1.13 ± 0.12 in the heavy sedation, respectively. ConclusionAn increase in the depth of sedation progressively decreases in oxygen consumption index and REEI in postoperative patients.

Preoperative administration of intravenous flurbiprofen axetil reduces postoperative pain for spinal fusion surgery.

PurposeThe aim of the study was to investigate postoperative analgesia and the opioid-sparing effect of the preoperative administration of intravenous flurbiprofen axetil in patients undergoing spinal fusion surgery.MethodsThirty-six patients were randomly allocated into one of three groups. Group A received preoperative flurbiprofen axetil, 1 mg·kg−1. Group B received postoperative flurbiprofen axetil, 1 mg·kg−1. Group C received a placebo. All groups were given a standardized anesthesia and intravenous morphine via a patient-controlled analgesia device for postoperative analgesia. The pain score was evaluated by a visual analog scale (VAS) at 0 (T0), 1 (T1), 2 (T2), 6 (T3), 12 (T4), and 24 (T5) h after surgery, and the morphine requirement was recorded during the study period.ResultsVAS in group A was significantly lower than that in group B at T0 and T1. VAS in group A was significantly lower than that in group C throughout the time course after surgery. Postoperative morphine consumption in group A was significantly lower than that in groups B and C at T0 to T3.ConclusionAs compared with postoperative administration, preoperative administration of intravenous flurbiprofen axetil provides better postoperative analgesia and an opioid-sparing effect in patients undergoing spinal fusion surgery under general anesthesia.

Increased incidence of emergency airway management after combined anterior-posterior cervical spine surgery.

Among some kinds of cervical spine surgeries, combined anterior-posterior cervical spine surgery (CAP-CS surgery) requires prolonged operative time and highly invasive procedure. This study was performed to determine whether CAP-CS surgery was associated with increased risk of emergency airway management compared with other cervical spine surgeries (O-CS surgeries). The records of the patients who underwent cervical spine surgery between July 2001 and March 2003 at our institution were reviewed retrospectively, and we determined whether the CAP-CS surgery was associated with an increased risk of emergency airway management in comparison with O-CS surgeries, using the logistic regression analysis. A total of 165 were eligible for inclusion in the study. A total of 127, 20, 11, 5, and 2 patients suffered from cervical myelopathy, traumatic cervical spinal cord injury, atlantoaxial dislocation, cervical spinal tumors, and cervical pyogenic spondylitis, respectively. The operative approaches were CAP-CS surgery, anterior surgery, posterior surgery, and atlantoaxial surgery in 10, 56, 88, and 11 patients, respectively. Thus, the operative approaches were CAP-CS surgery in 10 patients and O-CS surgeries in 155 patients. Postoperative emergency airway management was required in 7 of the 10 patients (70%) who underwent CAP-CS surgery, and 2 of the 155 patients (1%) who underwent O-CS surgeries. The increased risk of postoperative emergency airway management imposed by CAP-CS surgery was 178.5 by an odds ratio, with a 95% confidence interval of 25.6 to 1246. The results show that CAP-CS surgery provides a major risk factor for postoperative emergency airway management.

Sequential use of midazolam and propofol for long-term sedation in postoperative mechanically ventilated patients.

Acute withdrawal syndromes, including agitation and a long weaning time, are common adverse effects after long-term sedation with midazolam. We performed this study to determine whether the sequential use of midazolam and propofol could reduce adverse effects as compared with midazolam alone. We studied 26 patients receiving mechanical ventilation for three or more days after surgery. Patients were randomly assigned to two groups. In Group M, patients were sedated with midazolam alone. In Group M-P, midazolam was switched to propofol approximately 24 h before the expected stopping of sedation. The level of sedation was maintained at 4 or 5 on the Ramsay sedation scale. The sedation agitation scale was evaluated for 24 h after extubation. The recovery time from stopping of sedation to extubation was significantly shorter in Group M-P (1.3 ± 0.4 h) compared with Group M (4.0 ± 2.4 h). The incidence of agitation in Group M-P (8%) was significantly less frequent than that in Group M (54%). The results indicate that sequential use of midazolam and propofol for long-term sedation could reduce the incidence of agitation compared with midazolam alone.

Influence of low-molecular-weight hydroxyethyl starch on microvascular permeability in patients undergoing abdominal surgery : comparison with crystalloid

PurposeAdequate volume therapy is essential for stable hemodynamics and sufficient urinary output perioperatively. Hydroxyethyl starch (HES) has been reported to attenuate the microvascular hyperpermeability which occasionally occurs in surgical patients. This study was carried out to evaluate the effect of low-molecular-weight HES on the urinary microalbumin/creatinine ratio (MACR), a marker of microvascular permeability, in surgical patients.MethodsIn a prospective, controlled, and randomized clinical trial, 21 patients undergoing abdominal surgery were divided into two groups. Group HES (n = 10) received HES at 2 ml·kg−1·h−1 during surgery and at 1 ml·kg−1·h−1 after surgery, and additionally they received acetated Ringer’s solution (AR) at a rate to keep central venous pressure (CVP) 5 mm Hg. Group AR (n = 11) received AR at a rate to keep CVP at 3–5 mmHg. MACR, soluble intercellular adhesion molecule-1 (sICAM-1), and urinary output were measured intermittently in the perioperative period.ResultsMACR was significantly increased during surgery in both groups. There was no significant difference in MACR between the two groups throughout the study period. The serum concentration of sICAM-1 decreased during surgery in both groups, and that in group HES was significantly lower than that in group AR at the end of surgery. Postoperative urinary output in group HES was greater than that in group AR. The intensive care unit (ICU) stay in group HES was shorter than that in group AR.ConclusionAlthough low-molecular-weight HES does not improve microvascular hyperpermeability, the expansion of the intravascular volume by HES results in higher urinary output in the postoperative period than that seen with crystalloid solution. The lower concentration of sICAM-1 after surgery may be due to hemodilution.

Role of reactive oxygen in phospholipase A2 activation by ischemia/reperfusion of the rat kidney

AbstractPurpose. To investigate the role of phospholipase A2 (PLA2) in reperfusion injury of the kidney in an in vivo animal model, renal mitochondrial PLA2 activity was measured under three different conditions. Methods. Male Wistar rats (n = 72) anesthetized with pentobarbital underwent renal ischemia surgically for 45 min and were reperfused for the indicated time (renal ischemia/reperfusion). Treatments included reperfusion for various predetermined periods (phase 1), exposure to hyperbaric oxygen (phase 2), and administration of reactive oxygen species (ROS) scavenger (phase 3). Thereafter, each kidney was harvested, and mitochondrial PLA2 activity was measured by a radioisotope technique. Results. Ischemia/reperfusion resulted in time-related PLA2 activation in the renal mitochondria up to 48 h of reperfusion after renal ischemia. Renal mitochondrial PLA2 activity was further augmented by hyperbaric oxygen exposure prior to reperfusion, whereas administration of the ROS scavengers suppressed mitochondrial PLA2 activity. Conclusion. These data suggest that ROS may play an important role in the in vivo activation of PLA2 associated with renal ischemia/reperfusion.

Postoperative analgesic effect of preoperative intravenous flurbiprofen in arthroscopic rotator cuff repair

PurposeThis study was carried out to evaluate the postoperative analgesic effects of preoperative intravenous flurbiprofen in patients undergoing arthroscopic rotator cuff repair under general anesthesia.MethodsWe studied 44 patients who underwent an elective arthroscopic rotator cuff repair in a prospective, randomized, and double-blind fashion. The patients were divided into two groups. Group A (n = 22) received lipid emulsion 0.1 ml·kg−1 as a placebo, and group B (n = 22) received flurbiprofen 1 mg·kg−1 before the surgery. Intralipid or flurbiprofen was given intravenously 5 min before the surgery. General anesthesia was maintained with sevoflurane and nitrous oxide, and 10 ml of 0.75% ropivacaine was administered intraarticularly at the end of the surgery. Postoperative analgesia was supplied with intravenous 0.1 mg buprenorphine according to the patient’s demand. The effectiveness of flurbiprofen’s analgesic effect was measured by a visual analog scale (VAS) and by the amount of buprenorphine consumption at 0.5, 1, 2, 4, 6, 12, and 24 h after the surgery. Time to the first analgesic was also recorded.ResultsVAS in group B was significantly (P < 0.01) lower than that in group A during the first 6 h postoperatively. The amount of buprenorphine consumption in group B was also significantly (P < 0.01) less than that in group A within the first 2 h postoperatively. The time to first analgesic request in group B was significantly (P < 0.01) longer than that in group A.ConclusionThese results show that preoperative intravenous flurbiprofen facilitates the analgesic effect in the early postoperative period after arthroscopic rotator cuff repair.

Age-dependent relationship between bispectral index and sedation level

STUDY OBJECTIVE To determine the relationship between bispectral index (BIS) and sedation. DESIGN Prospective, observational clinical study. SETTING Intensive care unit of a public hospital in Japan. PATIENTS 22 ASA physical status I, II, and III middle-aged (18-65 yrs) and elderly (>65 yrs) patients receiving postoperative sedation with midazolam. INTERVENTIONS Patients were allocated to two groups: Group M was composed of middle-aged patients (<65 yrs) and Group H elderly patients (>65 yrs). Midazolam was administered at a bolus dose of 0.1 mg/kg, followed by a continuous dose of 0.04 mg/kg per hour, which was adjusted every two hours to achieve a target level of sedation at 3-6 on the Ramsay Sedation Scale (RSS); buprenorphine was administered at a constant rate (0.625 microg kg(-1) hr(-1)). MEASUREMENTS BIS value, RSS, midazolam dose, body temperature (BT), heart rate, dopamine dose, and mean arterial pressure were recorded every two hours by an independent nurse. Data were analyzed using Spearman rank correlation and the Mann-Whitney U test. MAIN RESULTS BIS values decreased depending on depth of sedation; a significant correlation was noted between groups in RSS and BIS. The BIS values at levels of RSS 5 and 6 were significantly lower in Group H than Group M. CONCLUSION BIS correlated with sedation depth, with BIS scores in group H than group M at a deep sedation depth.

Postoperative analgesia with minidose intrathecal morphine for bipolar hip prosthesis in extremely elderly patients.

PurposeIt is known that an optimal dose of intrathecal morphine for analgesia after total hip arthroplasty in older patients is 0.1 mg. On the other hand, minidose intrathecal morphine (0.05 mg) is useful for analgesia after the transurethral resection of the prostate in elderly patients. We evaluated the postoperative analgesic effect of minidose intrathecal morphine after bipolar hip prosthesis in seniors (age 85 years or more) undergoing spinal anesthesia.MethodsTwenty seniors undergoing bipolar hip prosthesis under spinal anesthesia were randomly allocated to one of two groups. Group A (n = 10) received intrathecal injection of 0.5% isobaric bupivacaine, 2.8 ml, and group B (n = 10) received intrathecal injection of 0.5% isobaric bupivacaine, 2.8 ml, plus morphine, 0.05 mg. Pain, nausea, and itching were evaluated using a numerical rating scale, ranging from 0 to 10, at 0, 4, 8, 12, and 24 h after the operation.ResultsThe values on the numerical rating scale for pain in group B were significantly lower than those in group A at 4, 8, and 12 h after the operation. There were no significant differences between the groups in the values on the numerical rating scale for nausea or itching throughout the time course of the study. No patient in either group showed hypoxemia or respiratory depression throughout the time course.ConclusionThe results show that minidose intrathecal morphine provides a good analgesic effect without side effects, and it would be an effective and safe procedure for bipolar hip prosthesis in seniors.

Admission microalbuminuria and neurologic outcomes in intensive care unit patients with spontaneous intracerebral hemorrhage.

This study was performed to determine the prevalence and the prognostic significance of microalbuminuria in patients admitted to intensive care unit (ICU) after spontaneous intracerebral hemorrhage (ICH). From May 2004 to April 2006, we studied 59 consecutive ICH patients verified using computed tomography and admitted to our ICU within a day after stroke. General clinical, neurologic data, and Glasgow Coma Scale (GCS) were recorded at admission to ICU. Urine was collected at admission to ICU for measuring the urinary microalbumin/creatinine ratio. At hospital discharge, neurologic outcome was assessed using Glasgow Outcome Scale. Among 59 patients, 37 (63%) had unfavorable neurologic outcomes (death, persistent vegetative state, and severe disability). The prevalence rate of microalbuminuria was 85% [95% confidence interval (CI), 76-94]. The areas under the receiver operator characteristic curves showed that the urinary microalbumin/creatinine ratio [0.81 (95% CI, 0.70-0.92)] and the GCS score [0.78 (95% CI, 0.66-0.90)] at admission were significant predictors of unfavorable neurologic outcome at hospital discharge. The threshold value, sensitivity, specificity, and likelihood ratio for the urinary microalbumin/creatinine ratio were 200 mg/g, 51% (95% CI, 39-64), 96% (95% CI, 90-100), and 11.3 (95% CI, 7.9-16.0); and those for the GCS score were 11, 46% (95% CI, 36-61), 96% (95% CI, 90-100), and 10.1 (95% CI, 7.2-14.1), respectively. This study confirmed a high prevalence of microalbuminuria in ICH patients in ICU, and suggested that the urinary microalbumin/creatinine ratio >200 mg/g was comparable to the GCS score <11 at admission to the ICU with regard to its prognostic characteristics after ICH.