Vomiting and Recovery after Outpatient Tonsillectomy and Adenoidectomy in Children: Comparison of Four Anesthetic Techniques Using Nitrous Oxide with Halothane or Propofol

Background: The authors' purpose in this study was to compare prospectively four different anesthetic induction and maintenance techniques using nitrous oxide with halothane and/or propofol for vomiting and recovery after outpatient tonsillectomy and adenoidectomy procedures in children.

Methods: Eighty unpremedicated children, aged 3-10 yr, were assigned randomly to four groups: group H/H, 0.5-2% halothane induction/halothane maintenance; group P/P, 3-5 mg *symbol* kg sup -1 propofol induction and 0.1-0.3 mg *symbol* kg sup -1 *symbol* min sup -1 propofol maintenance; group H/P, 0.1-0.3 mg *symbol* kg sup -1 *symbol* min sup -1 halothane induction/propofol maintenance; and group P/H, 3-5 mg *symbol* kg sup -1 propofol induction and 0.5-2% halothane maintenance. Nitrous oxide (67%) and oxygen (33%) were administered in all the groups. Other treatments and procedures were standardized intra- and postoperatively. Results of postoperative vomiting and recovery were analyzed in the first 6 h and beyond 6 h.

Results: Logistic regression showed that vomiting occurred 3.5 times as often when halothane was used for maintenance of anesthesia (groups H/H and P/H) compared with the use of propofol (groups P/P and H/P; Odds Ratio 3.5; 95% confidence interval 1.3 and 9.4, respectively; P = 0.012). A significant association between vomiting (< 6 h: yes/no) and discharge times (> 6 h: yes/no) (Odd's Ratio = 3.6; 95% confidence interval: 1.02, 12.4, respectively) (P = 0.046) was shown. However, no significant differences among the groups in the incidence of vomiting beyond 6 h, recurrent vomiting, or hospital discharge times were shown.     

The Use of Propofol, Nitrous Oxide, or Isoflurane Does Not Affect the Reproductive Success Rate following Gamete Intrafallopian Transfer (GIFT)

Background: Whether anesthetic agents administered during gamete intrafallopian transfer (GIFT) affect reproductive outcome is controversial. This multicenter pilot trial and survey had two purposes: to evaluate the effect of propofol, nitrous oxide, midazolam, and isoflurane on pregnancy outcome after GIFT, and to determine if a larger prospective, randomized study is warranted.

Methods: A written invitation was mailed to all 50 fertility programs in the United States that are members of the Society for Assisted Reproductive Technology and perform more than 30 GIFT procedures per year. They were invited to contribute information from the medical records of women who underwent GIFT during the calendar years 1993 and 1994. They were asked to document whether propofol, nitrous oxide, midazolam, a potent inhaled anesthetic agent was used during the GIFT procedure; if the woman became pregnant; and if she delivered at least one live neonate.

Results: Seven medical centers participated and contributed data from 455 women. The clinical pregnancy rate (number of pregnancies/total number of GIFT procedures) and the delivery rate (number of women who delivered at least one live baby/total number of GIFT procedures) were 35% and 32%, respectively. A statistically significant difference could not be found in the clinical pregnancy or delivery rates between those women who received propofol, nitrous oxide, midazolam, or isoflurane during GIFT and those who did not.     

Avoidance of Nitrous Oxide for Patients Undergoing Major Surgery: A Randomized Controlled Trial

Background: Nitrous oxide is widely used in anesthesia, often administered at an inspired concentration around 70%. Although nitrous oxide interferes with vitamin B12, folate metabolism, and deoxyribonucleic acid synthesis and prevents the use of high inspired oxygen concentrations, the consequences of these effects are unclear.

Methods: Patients having major surgery expected to last at least 2 h were randomly assigned to nitrous oxide-free (80% oxygen, 20% nitrogen) or nitrous oxide-based (70% N2O, 30% oxygen) anesthesia. Patients and observers were blind to group identity. The primary endpoint was duration of hospital stay. Secondary endpoints included duration of intensive care stay and postoperative complications; the latter included severe nausea and vomiting, and the following major complications: pneumonia, pneumothorax, pulmonary embolism, wound infection, myocardial infarction, venous thromboembolism, stroke, awareness, and death within 30 days of surgery.

Results: Of 3,187 eligible patients, 2,050 consenting patients were recruited. Patients in the nitrous oxide-free group had significantly lower rates of major complications (odds ratio, 0.71; 95% confidence interval, 0.56-0.89; P = 0.003) and severe nausea and vomiting (odds ratio, 0.40; 95% confidence interval, 0.31-0.51; P < 0.001), but median duration of hospital stay did not differ substantially between groups (7.0 vs. 7.1 days; P = 0.06). Among patients admitted to the intensive care unit postoperatively, those in the nitrous oxide-free group were more likely to be discharged from the unit on any given day than those in the nitrous oxide group (hazard ratio, 1.35; 95% confidence interval, 1.05-1.73; P = 0.02).     

Multivisceral Resection Does Not Affect Morbidity and Survival After Cytoreductive Surgery and Chemoperfusion for Carcinomatosis from Colorectal Cancer

Background  Carcinomatosis of colorectal origin is increasingly treated by cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CS-HIPEC). This procedure commonly involves multivisceral resection (MVR) with potentially high morbidity. We analyzed the effect of MVR on the outcome after CS-HIPEC. Methods  All patients with colorectal carcinomatosis operated between June 2001 and June 2007 were included. MVR was defined as resection of two or more organs (n = 35). Patients without any or with a single visceral resection formed a control group (n = 30). Results  Sixty-five patients underwent 72 procedures. MVR was not strongly associated with the mortality, morbidity, reoperation, or readmission. Morbidity, but not mortality, was more common in patients requiring bowel anastomosis (36 of 51 vs. 7 of 21, P = .003). Median survival from the diagnosis of carcinomatosis was not significantly different between the MVR and controls (32.8 months vs. 20.0 months, P = .787). Similarly, the median survival from the time of cytoreduction was not significantly different (20.2 vs. 14.3 months; P = .436). Independent predictors of survival in the Cox regression model were presence of residual disease >5 mm (hazard ratio = 4.5, P = .048), evidence of carcinomatosis on preoperative computed tomographic scan (6.1, P = .008), and initial diagnosis of cancer as systemic (2.6, P = .049). MVR had no statistically significant effect on survival (.441, P = .133). Conclusions  Increased risk of complications is associated with the number of intestinal anastomoses, but not with multivisceral resection in CS-HIPEC. Long-term survival is not affected by the number of resected organs.     

Bariatric Surgery Does Not Improve Semen Quality: Evidence from a Meta-analysis

Obesity Surgery - The meta-analysis aimed to explore the possible relationship between bariatric surgery and semen quality. PubMed, EMBASE, and CENTRAL were searched from database inception through...     

Pinealectomy Does Not Affect the Healing of Experimental Colonic Anastomoses

Gastrointestinal system anastomoses, especially colonic anastomoses, have significant morbidity and mortality despite recent technical improvements. Besides regulating the circadian rhythm, the pineal gland and its main neurohormone product melatonin have widespread actions in the organism. The purpose of this study was to investigate the effects of pinealectomy on the healing of colonic anastomoses. One hundred male albino Wistar rats were used in this study. The rats were separated into three groups: control, pinealectomy, and sham groups. In the control group, only colonic resection and anastomoses were performed. Following pinealectomy, colonic anastomosis was performed 2 weeks later on one half and 2 months later on the other half of the pinealectomy group. Only craniotomy was performed on the sham group, and the rats were separated and evaluated like the pinealectomy group. Colonic anastomoses were evaluated on postanastomotic day 3 and 7 by measuring the bursting pressure and the hydroxyproline levels in the anastomotic segments. There was no difference in the bursting pressure measurements between the groups on both postoperative day 3 and 7. Although hydroxyproline levels were different between groups on both postanastomotic days 3 and 7, it has been observed that neither normal nor anastomotic hydroxyproline levels influenced the anastomotic bursting pressure measurements. The percent deviation from the normal values was compared in the anastomotic segments, and no differences were found regarding the bursting pressure and hydroxyproline levels. It was concluded that pinealectomy has no effect on the healing of colonic anastomoses.     

Major Perioperative Morbidity Does Not Affect Long-Term Survival in Patients Undergoing Esophagectomy for Cancer of the Esophagus or Gastroesophageal Junction

Introduction

The incidence of cancer of the esophagus/GE junction is dramatically increasing but continues to have a dismal prognosis. Esophagectomy provides the best opportunity for long-term cure but is hampered by increased rates of perioperative morbidity. We reviewed our large institutional experience to evaluate the impact of postoperative complications on the long-term survival of patients undergoing resection for curative intent.

Methods

We identified 237 patients who underwent esophagogastrectomy, with curative intent, for cancer between 1994 and 2008. Complications were graded using the previously published Clavien scale. Survival was calculated using Kaplan–Meier methodology and survival curves were compared using log-rank tests. Multivariate analysis was performed with continuous and categorical variables as predictors of survival, and examined with logistic regression and odds ratio confidence intervals.

Results

There were 12 (5 %) perioperative deaths. The average age of all patients was 62 years, and the majority (82 %) was male. Complication grade did not significantly affect long-term survival, although patients with grade IV (serious) complications did have a decreased survival (p = 0.15). Predictors of survival showed that the minimally invasive type esophagectomy (p = 0.0004) and pathologic stage (p = 0.0007) were determining factors. There was a significant difference in overall survival among patients who experienced pneumonia (p = 0.00016) and respiratory complications (p = 0.0004), but this was not significant on multivariate analysis.

Conclusions

In this single-institution series, we found that major perioperative morbidity did not have a negative impact on long-term survival which is different than previous series. The impact of tumor characteristics at time of resection on long-term survival is of most importance.     

Omission of Nitrous Oxide during Anesthesia Reduces the Incidence of Postoperative Nausea and Vomiting: A Meta-Analysis

Background: Postoperative nausea and vomiting are important causes of morbidity after general anesthesia. Nitrous oxide has been implicated as an emetogenic agent in many studies. However, several other trials have failed to sustain this claim. The authors tried to resolve this issue through a meta-analysis of randomized controlled trials comparing the incidence of postoperative nausea and vomiting after anesthesia with or without nitrous oxide.

Methods: Of 37 published studies retrieved by a search of articles indexed on the MEDLINE database from 1966 to 1994, 24 studies (26 trials) with distinct nitrous-oxide and non-nitrous oxide groups were eligible for the meta-analysis. The pooled odds ratio and relative risk were calculated. Post hoc subgroup analysis was also performed to qualify the result.

Results: The pooled odds ratio was 0.63 (0.53 to 0.75). Omission of nitrous oxide reduced the risk for postoperative nausea and vomiting by 28% (18% to 37%). In the subgroup analysis, the maximal effect of omission of nitrous oxide was seen in female patients. In patients undergoing abdominal surgery and general surgical procedures, the effect of omission of nitrous oxide, although in the same direction, was not significant.     

Does Coronary Endarterectomy Adversely Affect the Results of Bypass Surgery?

Coronary endarterectomy (TEA) is performed infrequently during coronary artery bypass graft (CABG) surgery due to the impression that it results in higher rates of myocardial infarction (MI), operative mortality (OM), and poor long-term outcome. To assess the effectiveness of TEA, 1, 228 patients undergoing isolated CABG between 1982 and 1989 were evaluated. The incidence of OM (3.2%) and MI (6.0%) following TEA was similar to conventional CABG (OM = 3.8%, MI = 5.5%, p = NS). The incidence of low output syndrome (LOS, 15.1%) and intraaortic balloon pump insertion (IABP, 4.5%) following TEA was similar to conventional CABG (LOS = 12.6%, IABP = 6.0%, p = NS). The highest level of the cardiac specific isoenzyme (CK-MB) released following surgery was similar for the TEA group (46 ± 49) and conventional CABG group (42 ± 44, p = NS). Ventricular dysfunction, urgent surgery, left main stenosis, advanced age, and reoperative surgery were similar in the TEA and conventional CABG groups. At a mean follow-up of 4.2 years, 65.6% of all TEA patients were free of angina, 44.4% were gainfully employed, and 62% were in New York Heart Association Class I. The incidence of late myocardial infarction was 5.4%. The 5-year actuarial survival was 90%. Patients with double TEA and limited TEA (< 3 cm TEA specimens) tended to have a lower 5-year survival. With strict criteria for selection of TEA patients and with significant technical experience, the short- and long-term results of TEA are comparable to conventional CABG.     

Haemodynamic Changes with the Administration of Nitrous Oxide During Coronary Artery Surgery

Haemodynamic responses to 50% nitrous oxide in oxygen during coronary artery surgery were investigated in 10 patients. Morphine, diazepam and pancuronium were given intravenously as both induction and maintenance anaesthesia. A significant decrease was seen in heart rate, arterial pressure, pulmonary artery pressure, heart rale-systolic arterial pressure product, peripheral vascular resistance, left ventricular end-diastolic pressure, dP/dT of the left ventricle and resistance as measured in the graft to the left anterior descending coronary artery (LAD). No variations occurred in cardiac output, stroke volume, flow in the LAD-graft, pulmonary artery pressure or heart rate-systolic pulmonary artery pressure product or in dP/dT of the right ventricle. Pulmonary vascular resistance increased. It was concluded that left ventricular performance did not decrease and that no deterioration of the oxygenation to the myocardium seemed to occur.     

An Evaluation of the Effect of Anesthetic Technique on Reproductive Success after Laparoscopic Pronuclear Stage Transfer: Propofol/Nitrous Oxide Versus Isoflurane/Nitrous Oxide

Background: Laparoscopic pronuclear stage transfer (PROST) is the preferred method of embryo transfer after in vitro fertilization in many infertility programs. There are scant data to recommend the use or avoidance of any particular anesthetic agent for use in women undergoing this procedure. The authors hypothesized that propofol would be an ideal anesthetic for laparoscopic PROST because of its characteristic favorable recovery profile that includes minimal sedation and a low incidence of postoperative nausea and vomiting. The purpose of the study was to compare propofol and isoflurane with respect to postanesthetic recovery and pregnancy outcomes after laparoscopic PROST.

Methods: One hundred twelve women scheduled for laparoscopic PROST were randomized to receive either propofol/nitrous oxide or isoflurane/nitrous oxide for maintenance of anesthesia.

Results: Visual analog scale scores for sedation were lower in the propofol group than in the isoflurane group at all measurements between 30 min and 3 h after surgery. More women experienced emesis and were given an antiemetic during recovery in the isoflurane group than in the propofol group. However, the percentage of pregnancies with evidence of fetal cardiac activity was 54% in the isoflurane group compared with only 30% in the propofol group (P = 0.023). Also, the ongoing pregnancy rate was greater in the isoflurane group than in the propofol group (54% vs. 29%, P = 0.014).     

Foam During Reconstitution Does Not Affect the Potency of Botulinum Toxin Type A

BACKGROUND: Among factors that may affect the potency of botulinum toxin A (Botox), it is said that foam, together with bubbles, may cause surface denaturation of the toxin. OBJECTIVE: To determine whether the muscle relaxation effect of Botox is preserved and has the same duration when it is reconstituted in the presence of foam. METHODS: Six female volunteers, aged 42 to 56 years old, were treated for glabellar and periocular wrinkles. Each half of the face was treated with 16 U of Botox divided in four sites: three at the lateral orbital area and one at the medial brow, in the glabellar region. The right side received Botox gently reconstituted with saline to avoid foaming formation. The left side of the face was treated with Botox that was rapidly reconstituted in order to achieve as many bubbles as possible, even with shaking. Blinded observers compared pretreatment and posttreatment photographs and answered assessment-related questions. The results were analyzed clinically and statistically. RESULTS: There was no difference in muscle paralysis between treated sides in all patients, neither in early (15 days) nor late (4 months) follow-up evaluations. CONCLUSION: Botox maintains its potency even in the presence of foaming during the reconstitution process.     

Genetic Risk Score Does Not Predict the Outcome of Obesity Surgery

Background

We evaluated the benefit of using combined genetic risk score (GRS) of known single nucleotide polymorphisms (SNPs) for body mass index (BMI) and waist/hip ratio (WHR) in the prediction of weight loss and weight regain after obesity surgery.

Methods

A total of 163 consecutive morbidly obese individuals undergoing Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) in a single bariatric center in Finland were recruited. Fasting blood samples were drawn after 12 h of fasting before and 1 year after bariatric operation. Data for weight regain and medication were collected with a questionnaire after 3.1?±?2.7 years (mean ± SD) follow-up. Nonalcoholic steatohepatitis (NASH) was diagnosed with liver histology. Twenty BMI- and 13 WHR-related SNPs were genotyped. Linear regression was used to identify factors predicting weight loss and weight regain.

Results

Lower baseline BMI predicted greater decline in BMI (p?=?0.0005) and excess weight loss (EWL) (p?=?0.009). In the multiple linear regression analysis age and BMI, explained the variance of EWL during the first year while GRS, sex, fasting plasma glucose, serum insulin and NASH diagnosis did not have any effect. None of the baseline clinical variables explained BMI regain. The combined GRS did not associate with weight or BMI at baseline, with 1-year changes or with weight regain between 1 year and an average of 3.1 years follow-up.

Conclusions

In our study, we found that the genotype risk score does not predict weight loss after obesity surgery while lower baseline BMI predicted the greater weight loss.     

Parenteral Nutrition Does Not Improve Postoperative Recovery from Radical Cystectomy: Results of a Prospective Randomised Trial

Background

After radical cystectomy, patients are in a catabolic state because of postoperative stress response, extensive wound healing, and ileus.

Objective

To evaluate whether recovery can be improved with total parenteral nutrition (TPN) in patients following extended pelvic lymph node dissection (ePLND), cystectomy, and urinary diversion (UD).

Design, setting, and participants

We conducted a prospective, randomised, single-centre study of 157 consecutive cystectomy patients.

Intervention

Seventy-four patients (group A) received TPN during the first 5 postoperative days, with additional oral intake ad libitum. Eighty-three patients (group B) received oral nutrition alone.

Outcome measurements and statistical analysis

The primary outcome was the occurrence of postoperative complications. Secondary outcomes were time to recovery of bowel function, biochemical nutritional (serum albumin, serum prealbumin, serum total protein) and inflammatory (C-reactive protein) parameters, length of hospital stay, and costs attributed to the TPN. The Pearson χ² test was used for dichotomous variables; the Wilcoxon rank sum test was used for continuous variables.

Results and limitations

Postoperative complications occurred in 51 patients (69%) in group A and in 41 patients (49%) in group B (p = 0.013), a difference resulting from group A having more infectious complications than group B (32% vs 11%; p = 0.001). Serum prealbumin and serum total protein were significantly lower in group B on postoperative day 7 but not on postoperative day 12. Time to gastrointestinal recovery and length of hospital stay did not differ between the two groups. The costs for TPN were €614 per patient. A potential limitation is the use of a glucose-based parenteral nutrition without lipids.

Conclusions

Postoperative TPN is associated with a higher incidence of complications, mainly infections, and higher costs following ePLND, cystectomy, and UD versus oral nutrition alone.     

Changing from Isoflurane to Desflurane toward the End of Anesthesia Does Not Accelerate Recovery in Humans

Background: In an attempt to combine the advantage of the lower solubilities of new inhaled anesthetics with the lesser cost of older anesthetics, some clinicians substitute the former for the latter toward the end of anesthesia. The authors tried to determine whether substituting desflurane for isoflurane in the last 30 min of a 120-min anesthetic would accelerate recovery.

Methods: Five volunteers were anesthetized three times for 2 h using a fresh gas inflow of 2 l/min: 1.25 minimum alveolar concentration (MAC) desflurane, 1.25 MAC isoflurane, and 1.25 MAC isoflurane for 90 min followed by 30 min of desflurane concentrations sufficient to achieve a total of 1.25 MAC equivalent ("crossover"). Recovery from anesthesia was assessed by the time to respond to commands, by orientation, and by tests of cognitive function.

Results: Compared with isoflurane, the crossover technique did not accelerate early or late recovery (P > 0.05). Recovery from isoflurane or the crossover anesthetic was significantly longer than after desflurane (P < 0.05). Times to response to commands for isoflurane, the crossover anesthetic, and desflurane were 23 +/- 5 min (mean +/- SD), 21 +/- 5 min, and 11 +/- 1 min, respectively, and to orientation the times were 27 +/- 7 min, 25 +/- 5 min, and 13 +/- 2 min, respectively. Cognitive test performance returned to reference values 15-30 min sooner after desflurane than after isoflurane or the crossover anesthetic. Isoflurane cognitive test performance did not differ from that with the crossover anesthetic at any time.