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Biomedical subjects

S S Liu

Publications and source records attributed to S S Liu.

At least 37 records · Page 2Linked to original sources
PubMed2000

Sedation during spinal anesthesia.

BACKGROUND: Central neuraxial anesthesia has been reported to decrease the dose of both intravenous and inhalational anesthetics needed to reach a defined level of sedation. The mechanism behind this phenomenon is speculated to be decreased afferent stimulation of the reticular activating system. The authors performed a two-part study (nonrandomized pilot study and a subsequent randomized, double-blind, placebo-controlled study) using the Bispectral Index (BIS) monitor to quantify the degree of sedation in unmedicated volunteers undergoing spinal anesthesia. METHODS: Twelve volunteers underwent BIS monitoring and observer sedation scoring (Observer's Assessment of Alertness/Sedation Scale [OAA/S]) before and after spinal anesthesia with 50 mg hyperbaric lidocaine, 5%. Subsequently, 16 volunteers blinded to the study were randomized to receive spinal anesthesia with 50 mg hyperbaric lidocaine, 5% (n = 10) or placebo (n = 6) and underwent BIS and OAA/S monitoring. RESULTS: In part I, significant changes in BIS scores of the volunteers occurred progressively (P = 0.003). The greatest variations from baseline BIS measurement occurred at 30 and 70 min. In part II, there were significant decreases in OAA/S and self-sedation scores for patients receiving spinal anesthesia versuscontrol patients (P = 0.04 and 0. 01, respectively). The greatest decrease in OAA/S scores occurred at 60 min. BIS scores were similar between groups (P = 0.4). CONCLUSIONS: Spinal anesthesia is accompanied by significant sedation progressively when compared with controls as measured by OAA/S and self-sedation scores. This effect was not related to block height. The late sedation observed by OAA/S at 60 min may indicate a second mechanism of sedation, such as delayed rostral spread of local anesthetics. BIS was not a sensitive measure of the sedation associated with spinal anesthesia in the randomized, blinded portion of this study.

Adult↗
PubMed2000

Consumers' perceptions of health care: the case of Hong Kong.

The health care industry in Hong Kong has undergone major changes in organization as well as philosophy of operation since the 1970s. During this period, the Hong Kong government has also experienced a political transition from colonial status to a special administrative region of Mainland China. Because of the economic downturn in East Asia, including Hong Kong, contraction of public spending has compelled the government to reconsider the alternatives for health care provision in Hong Kong. A number of multinational health care providers have entered this market and operate mainly in the private sector, including solely-owned clinics and alliances with existing hospitals. This paper provides an understanding of the evolution and development of the health care industry in Hong Kong and, on that basis, suggests elements of quality health care from the findings of a survey of patients.

Consumer Behavior↗
PubMed2000

Effect of hypertension on the development of diabetic cardiomyopathy.

The effect of hypertension on the progression of diabetic cardiomyopathy was examined by attempting to induce a similar level of diabetes in both spontaneously hypertensive rats (SHR) and Wistar rats. Streptozotocin (STZ) was injected into SHR (45 mg/kg) and Wistar rats (55 mg/kg) before (eight weeks of age) and after (twelve weeks of age) the development of hypertension in the SHR. For both groups of animals, induction of diabetes resulted in depressed weight gain, increased food and fluid consumption, hypoinsulinemia, hyperglycemia, and hypertriglyceridemia. For the rats injected at eight weeks of age, an oral glucose tolerance test (OGTT) demonstrated that although the SHR were significantly less diabetic than Wistar rats, the degree of cardiac dysfunction was equivalent in both strains. These results suggest that hypertension was interacting with the diabetic condition to impair cardiac performance. Injecting SHR at twelve weeks of age increased the severity of diabetes but interestingly did not depress heart function compared with the non-diabetic SHR group. Injecting Wistar rats at this age also increased the severity of diabetes, but unlike the SHR diabetic animals, these rats still had impaired cardiac performance. These results suggest that hypertension exacerbates the cardiac dysfunction seen during diabetes, especially when SHR rats are injected with STZ prior to the elevation of blood pressure. Moreover, in the SHR, the development of LV hypertrophy at the time of STZ injection may have compensated for the damaging effects of diabetes on the myocardium, thereby enabling the heart to perform normally.

Age Factors↗
PubMed2000

Rapid assay of A1c-type glycosylated hemoglobin in blood of diabetic rats using fast protein liquid chromatography.

AIM: To develop a fast protein liquid chromatography (FPLC) method for the assay of Alc-type glycosylated hemoglobin in diabetic rats. METHODS: Venous blood was collected from rats. After the erythrocytes were washed and sedimented, the hemolysate was prepared and diluted with isotonic saline as a sample for the assay. Samples were then separated on Mono_S_HR_5/5 cation exchange column by a lithium chloride gradient elution system. The Alc-type glycosylated hemoglobin was monitored by measuring the absorbance at 415 nm. RESULTS: The Alc-type glycosylated hemoglobin was well separated from total hemoglobin. The average HbAlc amount in diabetic rats was determined to be (3.6% +/- 0.6%, n = 7), while the corresponding figure in normal rats was (1.4% +/- 0.4%, n = 7, P < 0.01). CONCLUSION: This FPLC method is easy, rapid and reproducible, and can be used for an assay of diabetic rat HbAlc to evaluate and screen new drugs for diabetes mellitus therapy.

Animals↗
PubMed2000

[Prediction and estimation on molar response values of alkanes by using molecular path vector].

A new method based on a novel molecular topological index vector, called the molecular path vector (MPV), of alkane molecules is proposed and employed for estimation and prediction of the molar response values of various alkanes. The novel MPV, p = (P1, P2, P3, P4, P5, P6, P7, P8, P9, P10)', which derived directly from the interaction terms of molecular graph, is used to characterize well molecular structures of all alkanes from one through ten or eleven carbon atoms. It showed that there exists very good correlation between the MPV elements and molar response values on both FID and TCD detectors in classical gas chromatography. Based on the given calibration set with different sample numbers and by using the practical multiple linear regression, the quantitative structure-response relationship (QSRR) equations, for the molar response values (SM) on both FID and TCD, are respectively given as follows: SM(FID) = 15.4004881 + 17.9905995 X1 - 0.1652116 X2 - 0.6974103 X3 - 0.8452390 X4 - 0.2671000 X5 - 1.5657273 X6 + 0.0944440 X7, n = 50, m = 7, r = 0.9976, ST = 26.132, SR = 1.965 1, Ev = 99.72%, RMS = 1.801, F = 1231.71 SM(TCD) = 11.9946996 + 29.1490916 X1 - 4.7451669 X2 - 3.7673385 X3 - 1.4948330 X4 - 1.6278831 X5 - 0.7934611 X6 - 3.0566093 X7, n = 32, m = 7, r = 0.9968, ST = 15.72, SR = 1.4310, Ev = 99.59%, RMS = 1.239, F = 531.227 where the independent descriptor variables, X1-X7, refer to the elements, P1, P2, P3, P4, P5, P6, P7 in the molecular path vector for all samples in both FID and TCD training sets; n, r, ST, SR, Ev, RMS and F are the sample number, regression coefficient, total standard deviation, standard residual deviation, explained variance, rooted mean squared error and F-statistic value, respectively. To test both models by using back-propagation neural network (BPNN) with the topological structure NN(7-4-2) and the cross validation through leave-one-out (LOO) procedure, the correlation coefficient of cross validation is over 0.96. Because there exists a quite good linear relationship between the molar responses and molecular path parameters, BPNN (r = 0.989 and 0.968) does not show its nonlinear advantage over multiple linear regression(MLR) (r = 0.9976 and 0.9968) in both presently examined cases, FID and TCD in the GC technique, for molecular modelling and quantitative prediction.

Alkanes↗
PubMed1999

Clinical significance of telomerase activation and telomeric restriction fragment (TRF) in cervical cancer.

Telomerase activation was examined in 50 cases of cervical cancer, 27 normal cervix and five cervical cancer cell lines using the sensitive polymerase chain reaction (PCR)-based TRAP (telomeric repeat amplification protocol) assay. Telomeric restriction fragment (TRF) length of these specimens was measured by Southern hybridisation. Telomerase activation was common in cervical cancers and was detected in 46/50 cases (92%). Telomerase activity was weak in normal cervix and was detected only in 2/27 cases (7.4%). Telomerase activity was detected in all stages of cervical cancer suggesting that it is an early event in cancer progression. The clinical significance of telomerase activation was analysed in 47 squamous cell carcinoma of the cervix. High telomerase activity was more frequently detected in advanced diseases (100% in stage III and stage IV cervical cancers combined) compared with early diseases (68.6% in stage I and stage II cancers combined). The difference was statistically significant (P < 0.02). Telomerase activity was not statistically correlated with other clinical parameters examined. This is the first report of telomeric length in human cervical cancer. Both shortening and elongation of TRF length in cervical cancers was observed. Advanced cervical cancers tended to have a wider range of variation of TRF length compared with early disease and normal cervix. There was no obvious relationship between TRF length and the clinical parameters examined including clinical staging, differentiation status of tumour, human papilloma virus (HPV) infection, recurrence rate, tumour size and invasion depth. The clinical significance of TRF length appears to be limited in cervical cancers. Our results indicate that telomerase activity is closely associated with tumour cells and may be useful as a marker for detection of tumour cells in cervical biopsies.

Adenocarcinoma↗
PubMed1999

Abnormal expression or mutation of TP53 and HPV in vulvar cancer.

HPV (human papillomavirus) plays an important role in cervical cancer and may also play a role in vulvar cancer. TP53 mutation is common in a variety of cancers but its role in vulvar cancer is not well established. The aim of this study was to assess the prevalence of HPV infection and TP53 mutation as well as their correlation in vulvar cancer. Also, HPV detection and abnormal p53 expression were assessed in relation to age, co-existing vulvar intraepithelial neoplasia and vulvar dystrophy. Forty-eight samples of vulvar cancer were studied. DNA was extracted from formalin-fixed paraffin embedded tissue for polymerase chain reaction/Southern blot study with HPV 16 and 18 and L1 primers. Paraffin sections were immunostained (IHS) for p53 protein using three antibodies, p1801, CM1 and DO7. The p53 mutation was also screened using polymerase chain reaction (PCR) single-stranded conformation polymorphism (SSCP) and confirmed by sequencing. Overall, HPV was detected in 48% (23/48), of which 96% (22/23) were HPV 16 or 18. By IHS, p53 overexpression was detected in 46% of cases whilst TP53 mutations were identified in 21%. In HPV positive and negative tumours, p53 abnormal expression was detected in 39% and 52%, respectively, and TP53 mutation was found in 22% and 20%, respectively. Mutations were mainly found at codons 273 and 204. Age was not found to be associated with HPV detection. However, the presence of HPV (71%) or absence of abnormal p53 expression (65%) were higher in tumours with VIN3, but were not correlated with dystrophy.

Aged↗
PubMed1999

Proto-oncogenes and p53 protein expression in normal cervical stratified squamous epithelium and cervical intra-epithelial neoplasia.

The aim of this study was to study the protein expression of six proto-oncogenes (epidermal growth factor receptor (EGFR), c-fms, c-myc, c-kit, c-erbB-2 and pan-ras) and one tumour suppressor gene (TP53), by immunohistochemical staining of normal cervical stratified squamous epithelium and cervical intra-epithelial neoplasia (CIN). Paraffin sections of 45 normal cervical specimens, 38 CIN grade one (CIN1), 37 CIN2 and 43 CIN3 were studied. An immunohistochemical (IHC) score was derived from the intensity of staining and the percentages of cells stained. In normal cervical specimens, a higher IHC score was found with EGFR and c-fms in superficial (S), intermediate (I) and parabasal (PB) cells compared with basal cells. In contrast, a higher IHC score was found with c-erbB-2 in basal cells in normal cervical specimens. Dysplastic cells in CIN had a higher IHC score with c-myc and c-erbB-2 than normal S/I and PB cells. Dysplastic cells had a higher score with EGFR than normal basal cells. However, a higher IHC score with EGFR and c-fms was found in normal S/I cells than dysplastic cells. These findings suggested that EGFR and c-fms were activated in more differentiated normal cells but were less active in less differentiated normal basal cells. However, EGFR was reactivated in dysplastic cells. Meanwhile, c-erbB-2 was activated in less differentiated normal basal cells and dysplastic cells, and was less active in differentiated normal cells. c-myc was activated in dysplastic cells. c-fms was more active in more differentiated normal cells and was not activated in less differentiated or dysplastic cells. c-kit, pan-ras and TP53 were not activated in normal nor dysplastic cervical cells. These results suggest EGFR, c-erbB-2 and c-myc may be important proto-oncogenes in CIN and that antibodies or anti-genes targeted against them may alter the progress of CIN to invasive cancer.

Female↗
PubMed1999

Cooperation of a "reactive oxygen cycle" with the Q cycle and the proton cycle in the respiratory chain--superoxide generating and cycling mechanisms in mitochondria.

Based on our recent findings concerning the generating, partitioning, targeting, and functioning of superoxide in mitochondria, a hypothetical model involving a "reactive oxygen cycle" in the respiratory chain has been proposed (Liu and Huang, 1991, 1996; Liu et al., 1996; Liu, 1997, 1998) This model emphasizes that during State 4 respiration, an interaction between an electron leak (a branch of electron transfer directly from the respiratory chain to form O2*-, but not H2O) and a proton leak (a branch pathway which utilizes delta muH+ to produce heat, but not ATP) may take place in cooperation with the Q and proton cycles in mitochondria through the consumption of H+ by O2*- anions to form a protonated perhydroxyl radical, HO2, which is directly permeable across the inner mitochondrial membrane and induces proton leakage and a decrease of delta muH+. O2*- generation in the mitochondrial respiratory chain and its cycling across the inner membrane may have the role of an endogenous protonophore in regulating and partitioning energy transduction and heat production, as well as in pathogenesis of mitochondrial diseases, aging, and apoptosis. The present article summarizes the supporting experimental evidence obtained in this laboratory and presents a brief description of the theoretical basis of this model.

Animals↗
PubMed1999

The neurotoxicity of drugs given intrathecally (spinal)

Overall, most spinal drugs in clinical use have been poorly studied for spinal cord and nerve root toxicity. Laboratory studies indicate that all local anesthetics are neurotoxic in high concentrations and that lidocaine and tetracaine have neurotoxic potential in clinically used concentrations. However, spinal anesthesia (including lidocaine and tetracaine) has a long and enviable history of safety. Spinal analgesics such as morphine, fentanyl, sufentanil, clonidine, and neostigmine seem to have a low potential for neurotoxicity based on laboratory and extensive clinical use. Most antioxidants, preservatives, and excipients used in commercial formulations seem to have a low potential for neurotoxicity. In addition to summarizing current information, we hope that this review stimulates future research on spinal drugs to follow a systematic approach to determining potential neurotoxicity. Such an approach would examine histologic, physiologic, and behavioral testing in several species, followed by cautious histologic, physiologic, and clinical testing in human volunteers and patients with terminal cancer refractory to conventional therapy.

Analgesics↗
PubMed1999

Dilution of spinal lidocaine does not alter the incidence of transient neurologic symptoms.

BACKGROUND: Although it has been suggested that the dilution of 5% hyperbaric lidocaine before injection for spinal anesthesia may decrease the incidence of transient neurologic symptoms, previous studies have not noted a decreased incidence between 5% and 2% lidocaine. The aim of the current study was to determine whether the incidence of transient neurologic symptoms could be altered by further diluting spinal lidocaine from 2.0% to 0.5%. METHODS: One hundred nine patients with American Society of Anesthesiologists physical status 1 or 2 undergoing outpatient knee arthroscopy were randomized in a double-blind fashion to receive 50 mg hyperbaric spinal lidocaine as a 2.0%, 1.0%, or 0.5% concentration. On the third postoperative day, patients were contacted by a blinded investigator and questioned regarding the incidence of postoperative complications, including transient neurologic symptoms, defined as pain or dysthesia in one or both buttocks or legs occurring within 24 h of surgery. RESULTS: The incidence of transient neurologic symptoms did not differ among patients receiving 2.0% (incidence of 15.8%), 1.0% (incidence of 22.2%), and 0.5% (incidence of 17.1%) lidocaine (P = 0.756). CONCLUSIONS: For ambulatory patients undergoing arthroscopy, the incidence of transient neurologic symptoms is not reduced by decreasing spinal lidocaine concentrations from 2.0% to 1.0% or 0.5%. The incidences of transient neurologic symptoms with the 0.5%, 1.0%, and 2.0% solutions are similar to previously reported incidences for 5.0% lidocaine, suggesting that dilution of lidocaine from 5.0% to 0.5% does not change the incidence of these symptoms.

Adult↗
PubMed1999

Dose-response effects of spinal neostigmine added to bupivacaine spinal anesthesia in volunteers.

BACKGROUND: Intrathecal adjuncts often are used to enhance small-dose spinal bupivacaine for ambulatory anesthesia. Neostigmine is a novel spinal analgesic that could be a useful adjunct, but no data exist to assess the effects of neostigmine on small-dose bupivacaine spinal anesthesia. METHODS: Eighteen volunteers received two bupivacaine spinal anesthetics (7.5 mg) in a randomized, double-blinded, crossover design. Dextrose, 5% (1 ml), was added to one spinal infusion and 6.25, 12.5, or 50 microg neostigmine in dextrose, 5%, was added to the other spinal. Sensory block was assessed with pinprick; by the duration of tolerance to electric stimulation equivalent to surgical incision at the pubis, knee, and ankle; and by the duration of tolerance to thigh tourniquet. Motor block at the quadriceps was assessed with surface electromyography. Side effects (nausea, vomiting, pruritus, and sedation) were noted. Hemodynamic and respiratory parameters were recorded every 5 min. Dose-response relations were assessed with analysis of variance, paired t tests, or Spearman rank correlation. RESULTS: The addition of 50 microg neostigmine significantly increased the duration of sensory and motor block and the time until discharge criteria were achieved. The addition of neostigmine produced dose-dependent nausea (33-67%) and vomiting (17-50%). Neostigmine at these doses had no effect on hemodynamic or respiratory parameters. CONCLUSIONS: The addition of 50 microg neostigmine prolonged the duration of sensory and motor block. However, high incidences of side effects and delayed recovery from anesthesia with the addition of 6.25 to 50 microg neostigmine may limit the clinical use of these doses for outpatient spinal anesthesia.

Adult↗
PubMed1999

Comparison of three solutions of ropivacaine/fentanyl for postoperative patient-controlled epidural analgesia.

BACKGROUND: Ropivacaine, 0.2%, is a new local anesthetic approved for epidural analgesia. The addition of 4 microg/ml fentanyl improves analgesia from epidural ropivacaine. Use of a lower concentration of ropivacaine-fentanyl may further improve analgesia or decrease side effects. METHODS: Thirty patients undergoing lower abdominal surgery were randomized in a double-blinded manner to receive one of three solutions: 0.2% ropivacaine-4 microg fentanyl 0.1% ropivacaine-2 microg fentanyl, or 0.05% ropivacaine-1 microg fentanyl for patient-controlled epidural analgesia after standardized combined epidural and general anesthesia. Patient-controlled epidural analgesia settings and adjustments for the three solutions were standardized to deliver equivalent drug doses. Pain scores (rest, cough, and ambulation), side effects (nausea, pruritus, sedation, motor block, hypotension, and orthostasis), and patient-controlled epidural analgesia consumption were measured for 48 h. RESULTS: All three solutions produced equivalent analgesia. Motor block was significantly more common (30 vs. 0%) and more intense with the 0.2% ropivacaine-4 microg fentanyl solution. Other side effects were equivalent between solutions and mild in severity. A significantly smaller volume of 0.2% ropivacaine-4 microg fentanyl solution was used, whereas the 0.1% ropivacaine-2 microg fentanyl group used a significantly greater amount of ropivacaine and fentanyl. CONCLUSIONS: Lesser concentrations of ropivacaine and fentanyl provide comparable analgesia with less motor block despite the use of similar amounts of ropivacaine and fentanyl. This finding suggests that concentration of local anesthetic solution at low doses is a primary determinant of motor block with patient-controlled epidural analgesia after lower abdominal surgery.

Amides↗
PubMed1999

Hyperbaric spinal ropivacaine: a comparison to bupivacaine in volunteers.

BACKGROUND: Ropivacaine is a newly introduced local anesthetic that may be a useful alternative to low-dose bupivacaine for outpatient spinal anesthesia. However, its relative potency to bupivacaine and its dose-response characteristics are unknown. This double-blind, randomized, crossover study was designed to determine relative potencies of low-dose hyperbaric spinal ropivacaine and bupivacaine and to assess the suitability of spinal ropivacaine for outpatient anesthesia. METHODS: Eighteen healthy volunteers were randomized into three equal groups to receive one spinal administration with bupivacaine and a second with ropivacaine, of equal-milligram doses (4, 8, or 12 mg) of 0.25% drug with 5% dextrose. The duration of blockade was assessed with (1) pinprick, (2) transcutaneous electrical stimulation, (3) tolerance to high tourniquet, (4) electromyography and isometric force dynamometry, and (5) achievement of discharge criteria. Differences between ropivacaine and bupivacaine were assessed with linear and multiple regression. P < 0.05 was considered significant. RESULTS: Ropivacaine and bupivacaine provided dose-dependent prolongation of sensory and motor block and time until achievement of discharge criteria (R2 ranges from 0.33-0.99; P values from < 0.001 through 0.01). Spinal anesthesia with ropivacaine was significantly different from bupivacaine and was approximately half as potent for all criteria studied. A high incidence of back pain (28%; P = 0.098) was noted after intrathecal ropivacaine was given. CONCLUSION: Ropivacaine is half as potent and in equipotent doses has a similar profile to bupivacaine with a higher incidence of side effects. Low-dose hyperbaric spinal ropivacaine does not appear to offer an advantage over bupivacaine for use in outpatient anesthesia.

Adult↗
PubMed1999

Does epidural anesthesia have general anesthetic effects? A prospective, randomized, double-blind, placebo-controlled trial.

BACKGROUND: Clinically, patients require surprisingly low end-tidal concentrations of volatile agents during combined epidural-general anesthesia. Neuraxial anesthesia exhibits sedative properties that may reduce requirements for general anesthesia. The authors tested whether epidural lidocaine reduces volatile anesthetic requirements as measured by the minimum alveolar concentration (MAC) of sevoflurane for noxious testing cephalad to the sensory block. METHODS: In a prospective, randomized, double-blind, placebo-controlled trial, 44 patients received 300 mg epidural lidocaine (group E), epidural saline control (group C), or epidural saline-intravenous lidocaine infusion (group I) after premedication with 0.02 mg/kg midazolam and 1 microg/kg fentanyl. Tracheal intubation followed standard induction with 4 mg/kg thiopental and succinylcholine 1 mg/kg. After 10 min or more of stable end-tidal sevoflurane, 10 s of 50 Hz, 60 mA tetanic electrical stimulation were applied to the fifth cervical dermatome. Predetermined end-tidal sevoflurane concentrations and the MAC for each group were determined by the up-and-down method and probit analysis based on patient movement. RESULTS: MAC of sevoflurane for group E, 0.52+/-0.18% (+/- 95% confidence interval [CI]), differed significantly from group C, 1.18+/-0.18% (P < 0.0005), and from group I, 1.04+/-0.18% (P < 0.001). The plasma lidocaine levels in groups E and I were comparable (2.3+/-1.0 vs. 3.0+/-1.2 microg/ml +/- SD). CONCLUSIONS: Lidocaine epidural anesthesia reduced the MAC of sevoflurane by approximately 50%. This MAC sparing is most likely caused by indirect central effects of spinal deafferentation and not to systemic effects of lidocaine or direct neural blockade. Thus, lower concentrations of volatile agents than those based on standard MAC values may be adequate during combined epidural-general anesthesia.

Adult↗
PubMed1999

Sputum induction to improve the diagnostic yield in patients with suspected pulmonary tuberculosis.

OBJECTIVE: To evaluate the utility of sputum induction in the large-scale tuberculosis control program. METHODS: Prospective study on sputum induction for improving the diagnostic yield of pulmonary tuberculosis, and estimation of the direct costs for sputum induction. RESULTS: Of 1,648 tuberculosis suspects with poor or absent sputum production, induced sputum was smear-positive in 558 patients (353 previously smear-negative, 97 inadequate sputum and 108 unproductive). The direct cost per induced sputum was US $0.37. CONCLUSION: Sputum induction is an effective, low-cost, and simple technique for improving the smear-positive case detection rate in a tuberculosis control program.

Adolescent↗
PubMed1998

Standardized perioperative care protocols and reduced length of stay after colon surgery.

BACKGROUND: Recent studies have suggested that critical pathways and standard order sets decrease hospital length of stay and improve quality of care. A recently conducted prospective, randomized study at our institution found that patients undergoing elective colon resections had earlier return of bowel function if perioperative epidural anesthesia and analgesia were provided. All patients in the study were also placed on a standardized perioperative regimen. We hypothesized that the standardized perioperative protocol used in this study contributed to early return of bowel function and hospital discharge compared with similar patients managed off protocol. STUDY DESIGN: To test this hypothesis, we performed a case-controlled study comparing the hospital courses of 36 study patients to 36 control patients undergoing colorectal surgery by the same surgeons during the same calendar year. The distribution of types of operations and anesthetic techniques was similar in both groups. RESULTS: As dictated by the protocol, all study patients had their nasogastric tubes removed, were started on a low fat liquid diet, and ambulated in the first postoperative day. Nasogastric tubes were removed in control patients and study patients 2.2 +/- 0.9 (mean value +/- SD) and 1.0 +/- 0.0 days postoperatively, respectively. Control patients were started on an oral diet, usually clear liquids, an average of 2.9 +/- 1.1 days postoperatively, a specific liquid diet was started 1.0 day postoperatively in study patients (p < 0.001). Return of bowel function, as determined by bowel tones, flatus, and bowel movements, occurred approximately 1 day earlier in study patients. Study patients were discharged 1 day sooner than control patients. CONCLUSIONS: Our results suggest that the return of bowel function and the length of stay of patients undergoing colon surgery are improved if patients are entered into a standardized protocol that eliminates variation in intraoperative and postoperative anesthesia and postoperative surgical care. We believe these results can be reproduced in routine clinical surgery by having a clearly outlined protocol for perioperative care similar to that used in this study.

Analgesia, Epidural↗