Biomedical subjects

Kari Korttila

Publications and source records attributed to Kari Korttila.

4 recordsLinked to original sources

PubMed2004

A factorial trial of six interventions for the prevention of postoperative nausea and vomiting.

BACKGROUND: Untreated, one third of patients who undergo surgery will have postoperative nausea and vomiting. Although many trials have been conducted, the relative benefits of prophylactic antiemetic interventions given alone or in combination remain unknown. METHODS: We enrolled 5199 patients at high risk for postoperative nausea and vomiting in a randomized, controlled trial of factorial design that was powered to evaluate interactions among as many as three antiemetic interventions. Of these patients, 4123 were randomly assigned to 1 of 64 possible combinations of six prophylactic interventions: 4 mg of ondansetron or no ondansetron; 4 mg of dexamethasone or no dexamethasone; 1.25 mg of droperidol or no droperidol; propofol or a volatile anesthetic; nitrogen or nitrous oxide; and remifentanil or fentanyl. The remaining patients were randomly assigned with respect to the first four interventions. The primary outcome was nausea and vomiting within 24 hours after surgery, which was evaluated blindly. RESULTS: Ondansetron, dexamethasone, and droperidol each reduced the risk of postoperative nausea and vomiting by about 26 percent. Propofol reduced the risk by 19 percent, and nitrogen by 12 percent; the risk reduction with both of these agents (i.e., total intravenous anesthesia) was thus similar to that observed with each of the antiemetics. All the interventions acted independently of one another and independently of the patients' baseline risk. Consequently, the relative risks associated with the combined interventions could be estimated by multiplying the relative risks associated with each intervention. Absolute risk reduction, though, was a critical function of patients' baseline risk. CONCLUSIONS: Because antiemetic interventions are similarly effective and act independently, the safest or least expensive should be used first. Prophylaxis is rarely warranted in low-risk patients, moderate-risk patients may benefit from a single intervention, and multiple interventions should be reserved for high-risk patients.

Anesthesia, General↗

PubMed2003

An international multicenter protocol to assess the single and combined benefits of antiemetic interventions in a controlled clinical trial of a 2x2x2x2x2x2 factorial design (IMPACT).

For various diseases clinicians have to combine different drugs or interventions when a single drug or intervention does not lead to satisfactory results. However, quantifying the relative benefit of certain drugs or interventions when given alone and in combination under controlled conditions requires a complex factorial design. This paper describes such a method applied to a large multicenter trial for the prevention of postoperative nausea and vomiting (PONV), which may be of great interest for other specialties. Approximately 28 million operations are performed annually in the United States, mainly under general anesthesia with volatile anesthetics. Unfortunately, one-third of these patients suffer from PONV. This prompted extensive research of antiemetic and anesthetic drugs, but none of the interventions appeared to satisfactorily prevent PONV. Scuderi et al. were the first to almost eliminate PONV by combining various antiemetic interventions; however, the relative benefit of each intervention remained unclear. Accordingly, we have designed a large randomized controlled trial studying six different antiemetic interventions-three involving use of various antiemetic drugs and three involving choice of anesthetic drugs-to answer the following main questions: (1) What is the relative benefit of each of the antiemetic intervention? (2) Are certain combinations of antiemetic interventions more effective than others? Using a complete factorial design this leads to 2(3)=8 antiemetic combinations, which multiply with the 2(3)=8 combinations of anesthetic drugs, leading to a total of 2(6)=64 possible combinations. The six factors are the antiemetics ondansetron (versus control), dexamethasone (versus control), droperidol (versus control), and the intravenous anesthetic propofol (versus volatile anesthetics), air (versus nitrous oxide), and remifentanil (versus fentanyl). The primary outcome is freedom from PONV within the first 24 hours after anesthesia. Eligible patients are adults scheduled for elective surgery under general anesthesia with an increased risk for PONV so that the expected incidence in the control group (with none of the six antiemetic interventions) is approximately 60%. In order to allow analyses for up to three factor interactions, a sample size was estimated to be in the range of approximately 5000 patients. To the best of our knowledge this is the first randomized controlled trial of a six-way factorial design that may serve as an example for numerous other medical specialties.

Anesthesia, Inhalation↗

PubMed2002

Postoperative cognitive dysfunction in middle-aged patients.

BACKGROUND: Postoperative cognitive dysfunction (POCD) after noncardiac surgery is strongly associated with increasing age in elderly patients; middle-aged patients (aged 40-60 yr) may be expected to have a lower incidence, although subjective complaints are frequent. METHODS: The authors compared the changes in neuropsychological test results at 1 week and 3 months in patients aged 40-60 yr, using a battery of neuropsychological tests, with those of age-matched control subjects using Z-score analysis. They assessed risk factors and associations of POCD with measures of subjective cognitive function, depression, and activities of daily living. RESULTS: At 7 days, cognitive dysfunction as defined was present in 19.2% (confidence interval [CI], 15.7-23.1) of the patients and in 4.0% (CI, 1.6-8.0) of control subjects (P < 0.001). After 3 months, the incidence was 6.2% (CI, 4.1-8.9) in patients and 4.1% (CI, 1.7-8.4) in control subjects (not significant). POCD at 7 days was associated with supplementary epidural analgesia and reported avoidance of alcohol consumption. At 3 months, 29% of patients had subjective symptoms of POCD, and this finding was associated with depression. Early POCD was associated with reports of lower activity scores at 3 months. CONCLUSIONS: Postoperative cognitive dysfunction occurs frequently but resolves by 3 months after surgery. It may be associated with decreased activity during this period. Subjective report overestimates the incidence of POCD. Patients may be helped by recognition that the problem is genuine and reassured that it is likely to be transient.

Adult↗

PubMed2002

Eliminating intensive postoperative care in same-day surgery patients using short-acting anesthetics.

BACKGROUND: A multidisciplinary effort was undertaken to determine whether patients could safely bypass the postanesthesia care unit (PACU) after same-day surgery by moving to an earlier time point evaluation of recovery criteria. METHODS: A prospective, outcomes research study with a baseline month, an intervention month, and a follow-up month was designed. Five surgical centers (three community-based hospitals and two freestanding ambulatory surgical centers) were utilized. Two thousand five hundred eight patients were involved in the baseline period, and 2,354 were involved in the follow-up period. Outcome measures included PACU bypass rates and adverse events. Intervention consisted of a multidisciplinary educational program and routine feedback reports. RESULTS: The overall PACU bypass rate (58%) was significantly different from baseline (15.9%, P < 0.001), for patients to whom a general anesthetic was administered (0.4-31.8%, P < 0.001), and for those given other anesthetic techniques (monitored anesthesia care, regional or local anesthetics; 29.1-84.2%, P < 0.001). During the follow-up period, the average (SD) recovery duration for patients who bypassed the PACU was significantly shorter compared to that for patients who did not bypass, 84.6 (61.5) versus 175.1 (98.8) min, P < 0.001, with no change in patient outcome. Patients receiving only short-acting anesthetics were 78% more likely (P < 0.002) to bypass the PACU after adjusting for various surgical procedures. CONCLUSIONS: This study represents a substantial change in clinical practice in the perioperative setting. Same-day surgical patients given short-acting anesthetic agents and who are awake, alert, and mobile requiring no parenteral pain medications and with no bleeding or nausea at the end of an operative procedure can safely bypass the PACU.

Adult↗