Kerstin Kolodzie

Nausea and vomiting after office-based anesthesia.

Purpose of the review Safety, quality, and patient satisfaction are not only defined by the incidences of serious adverse events but also include postoperative outcomes such as postdischarge nausea and vomiting (PDNV). PDNV has a high impact on patient recovery and may influence the cost-effectiveness of office-based surgical procedures. This article reviews the incidences and risk factors for PDNV as well as medications and concepts for prophylaxis and treatment. Recent findings Patients with PDNV require a longer recovery time to resume normal activities. PDNV can delay discharge from postanesthesia care units and is one of the leading causes of unexpected hospital admission after planned outpatient surgery. New data indicate that the incidence of PDNV is higher than expected and therefore we need a model that allows us to identify patients at risk for PDNV. A PDNV prediction model will help clinicians to better identify patients at risk who might benefit from long-acting antiemetics such as transdermal scopolamine, aprepitant, and/or palonosetron. Summary PDNV is an under-recognized problem after outpatient anesthesia. Valid data for the incidence and the best treatment of PDNV after office-based anesthesia are rare. For safety, quality, and patient satisfaction, further research is needed to develop a prediction model to better identify patients at risk for PDNV in order to direct antiemetic prophylaxis for ambulatory patients undergoing office-based anesthesia.

Droperidol has comparable clinical efficacy against both nausea and vomiting

BACKGROUND Droperidol is commonly noted to be more effective at preventing postoperative nausea (PON) than vomiting (POV) and it is assumed to have a short duration of action. This may be relevant for clinical decisions, especially for designing multiple-drug antiemetic regimens. METHODS We conducted a post hoc analysis of a large multicentre trial. Within this trial, 1734 patients underwent inhalation anaesthesia and were randomly stratified to receive several antiemetic interventions according to a factorial design, one of which was droperidol 1.25 mg vs placebo. We considered differences to be significant when: (i) point estimates of one outcome are not within the limits of the confidence interval (CI) of the other outcome; and (ii) differences in risk ratio (also known as relative risks, RR) are at least 20%. RESULTS Over 24 h, nausea was reduced from 42.9% in the control to 32.0% in the droperidol group, corresponding to a relative risk (RR) of 0.75 (95% CI from 0.66 to 0.84). Vomiting was reduced from 15.6% to 11.8%, and therefore associated with a similar RR of 0.76 (0.59-0.96). In the early postoperative period (0-2 h), droperidol prevented nausea and vomiting similarly, with an RR of 0.57 (0.46-0.69) for nausea and 0.56 (0.37-0.85) for vomiting. In the late postoperative period (2-24 h), the RR was again similar with 0.83 (0.72-0.96) for nausea compared with 0.89 (0.66-1.18) for vomiting but significantly less compared with the early postoperative period. CONCLUSIONS We conclude that droperidol prevents PON and POV equally well, yet its duration of action is short-lived.

Postoperative Pulmonary Complications, Early Mortality, and Hospital Stay Following Noncardiothoracic Surgery: A Multicenter Study by the Perioperative Research Network Investigators

Importance Postoperative pulmonary complications (PPCs), a leading cause of poor surgical outcomes, are heterogeneous in their pathophysiology, severity, and reporting accuracy. Objective To prospectively study clinical and radiological PPCs and respiratory insufficiency therapies in a high-risk surgical population. Design, Setting, and Participants We performed a multicenter prospective observational study in 7 US academic institutions. American Society of Anesthesiologists physical status 3 patients who presented for noncardiothoracic surgery requiring 2 hours or more of general anesthesia with mechanical ventilation from May to November 2014 were included in the study. We hypothesized that PPCs, even mild, would be associated with early postoperative mortality and use of hospital resources. We analyzed their association with modifiable perioperative variables. Exposure Noncardiothoracic surgery. Main Outcomes and Measures Predefined PPCs occurring within the first 7 postoperative days were prospectively identified. We used bivariable and logistic regression analyses to study the association of PPCs with ventilatory and other perioperative variables. Results This study included 1202 patients who underwent predominantly abdominal, orthopedic, and neurological procedures. The mean (SD) age of patients was 62.1 (13.8) years, and 636 (52.9%) were men. At least 1 PPC occurred in 401 patients (33.4%), mainly the need for prolonged oxygen therapy by nasal cannula (n = 235; 19.6%) and atelectasis (n = 206; 17.1%). Patients with 1 or more PPCs, even mild, had significantly increased early postoperative mortality, intensive care unit (ICU) admission, and ICU/hospital length of stay. Significant PPC risk factors included nonmodifiable (emergency [yes vs no]: odds ratio [OR], 4.47, 95% CI, 1.59-12.56; surgical site [abdominal/pelvic vs nonabdominal/pelvic]: OR, 2.54, 95% CI, 1.67-3.89; and age [in years]: OR, 1.03, 95% CI, 1.02-1.05) and potentially modifiable (colloid administration [yes vs no]: OR, 1.75, 95% CI, 1.03-2.97; preoperative oxygenation: OR, 0.86, 95% CI, 0.80-0.93; blood loss [in milliliters]: OR, 1.17, 95% CI, 1.05-1.30; anesthesia duration [in minutes]: OR, 1.14, 95% CI, 1.05-1.24; and tidal volume [in milliliters per kilogram of predicted body weight]: OR, 1.12, 95% CI, 1.01-1.24) factors. Conclusions and Relevance Postoperative pulmonary complications are common in patients with American Society of Anesthesiologists physical status 3, despite current protective ventilation practices. Even mild PPCs are associated with increased early postoperative mortality, ICU admission, and length of stay (ICU and hospital). Mild frequent PPCs (eg, atelectasis and prolonged oxygen therapy need) deserve increased attention and intervention for improving perioperative outcomes.

4-chloro-m-cresol is a trigger of malignant hyperthermia in susceptible swine.

BACKGROUND 4-Chloro-m-cresol (4-CmC) induces marked contractures in skeletal muscle specimens from individuals susceptible to malignant hyperthermia (MHS). In contrast, 4-CmC induces only small contractures in specimens from normal (MHN) patients. 4-CmC is a preservative within a large number of commercially available drug-preparations (e.g., insulin, heparin, succinylcholine), and it has been suggested that 4-CmC might trigger malignant hyperthermia. This study was designed to investigate the effects of 4-CmC in vivo and in vitro in the same animals. METHODS After approval of the animal care committee, six Pietrain MHS and six control (MHN) swine were anesthetized with azaperone 4 mg/kg intramuscularly and metomidate 10 mg/kg intraperitoneally. After endotracheal intubation, lungs were mechanically ventilated (inspired oxygen fraction 0.3) and anesthesia was maintained with etomidate 2.5 mg x kg(-1) x h(-1) and fentanyl 50 microg x kg(-1) x h(-1). Animals were surgically prepared with arterial and central venous catheters for measurement of hemodynamic parameters and to obtain blood samples. Before exposure to 4-CmC in vivo, muscle specimens were excised for in vitro contracture tests with 4-CmC in concentrations of 75 and 200 microM. Subsequently, pigs were exposed to cumulative administration of 3, 6, 12, 24, and 48 mg/kg 4-CmC intravenously. If an unequivocal episode of malignant hyperthermia occurred, as indicated by venous carbon dioxide concentration > or = 70 mmHg, pH < or = 7.25, and an increase of temperature > or = 2 degrees C, the animals were treated with dantrolene, 3.5 mg/kg. RESULTS All MHS swine developed malignant hyperthermia after administration of 4-CmC in doses of 12 or 24 mg/kg. Venous carbon dioxide concentration significantly increased and pH significantly decreased. Temperature increased in all MHS animals more than 2 degrees C. Blood lactate concentrations and creatine kinase levels were significantly elevated. All MHS swine were treated successfully with dantrolene. In contrast, no MHN swine developed signs of malignant hyperthermia. After receiving 4-CmC in a concentration of 48 mg/kg, however, all MHN animals died by ventricular fibrillation. The in vitro experiments showed that both concentrations of 4-CmC produced significantly greater contractures in MHS than in MHN specimens. CONCLUSIONS 4-CmC is in vivo a trigger of malignant hyperthermia in swine. However, the 4-CmC doses required for induction of malignant hyperthermia were between 12 and 24 mg/kg, which is about 150-fold higher than the 4-CmC concentrations within clinically used preparations.

The effect of postoperative fasting on vomiting in children and their assessment of pain

Background:  Mandatory postoperative food intake has been shown to increase nausea and vomiting, and so postoperative fasting has become common practice even if patients request food or drink.

Phosphodiesterase-III-inhibition with amrinone leads to contracture development in skeletal muscle preparations of malignant hyperthermia susceptible swine

Background and objective: The phosphodiesterase‐III (PDE‐III) inhibitor enoximone‐induced marked contractures in skeletal muscle specimens of malignant hyperthermia (MH) susceptible (MHS) human beings and swine. Whether this is a substance specific effect of enoximone or caused by inhibition of PDE‐III remained unclear. Therefore, the effects of the PDE‐III inhibitor amrinone in porcine MH normal (MHN) and MHS skeletal muscles were investigated. Methods: MH‐trigger‐free general anaesthesia was performed in eight MHS and eight MHN swine. The MH status of the swine was determined by detection of the Arg615‐Cys point mutation on chromosome 6 indicating MH susceptibility. Skeletal muscle specimens were excised for the in vitro contracture tests with amrinone. Amrinone was added cumulatively every 5 min to muscle specimens in order to obtain organ bath concentrations between 20 and 400 μmol L−1. The in vitro effects of amrinone on muscle contractures and twitches were measured. Results: Amrinone‐induced contractures in all skeletal muscle preparations. MHS muscles developed contractures at significantly lower bath concentrations of amrinone than MHN muscles. Contractures of MHS compared to MHN muscles were significantly larger at bath concentrations of 80, 100, 150, 200 and 400 μmol L−1 amrinone. Muscle twitches remained unchanged up to and including 200 μmol L−1 amrinone. Conclusions: Inhibition of PDE‐III in general elicited higher contractures in MHS than in MHN muscles. Therefore, a contribution of PDE‐III and the cyclic adenosine monophosphate (cAMP) system in the pathophysiology of MH must be suspected.

Cumulative and bolus in vitro contracture testing with 4-chloro-3-ethylphenol in malignant hyperthermia positive and negative human skeletal muscles.

In this study we evaluated the in vitro effects of 4-chloro-3-ethylphenol (CEP) using cumulative (12.5–200 &mgr;mol/L) or bolus (75 and 100 &mgr;mol/L) administrations, on muscle specimens from malignant hyperthermia (MH) susceptible and MH nonsusceptible patients, respectively. In the cumulative CEP in vitro contracture test, contractures were significantly greater in the MH susceptible compared with the MH nonsusceptible muscles in all concentrations between 25 and 100 &mgr;mol/L. There was no overlap between the diagnostic groups at 75 &mgr;mol/L of CEP, so this test appears to be feasible for diagnosis of MH susceptibility. The two bolus tests are not diagnostically useful, as overlaps between the diagnostic groups were observed.

Anesthesia management of patients undergoing hyperthermic isolated limb perfusion with melphalan for melanoma treatment: an analysis of 17 cases

BackgroundHyperthermic isolated limb perfusion (HILP) is used for patients with intractable or extensive in-transit metastatic melanoma of the limb to deliver high concentrations of cytotoxic agents to the affected limb and offers a treatment option in a disease stage with a poor prognosis when no treatment is given.MethodsIn a retrospective chart review of 17 cases, we studied the anesthetic and hemodynamic changes during HILP and its management.ResultsHILP was well tolerated except in one case that is described herein. We present summary data of all cases undergoing upper and lower limb perfusion, discuss our current clinical practice of preoperative, perioperative and intraoperative patient care including the management of HILP circuit.ConclusionHILP is a challenging procedure, and requires a team effort including the surgical team, anesthesia care providers, perfusionists and nurses. Intraoperatively, invasive hemodynamic and metabolic monitoring is indispensable to manage significant hemodynamic and metabolic changes due to fluid shifts and release of cytokines.

Inhibition of sarcoplasmic Ca2+ adenosine triphosphatase in porcine skeletal muscle samples with cyclopiazonic acid enables in vitro malignant hyperthermia discrimination.

IT is generally accepted that malignant hyperthermia (MH) susceptibility is caused by an abnormal Ca metabolism within the skeletal muscle cell. Ca homeostasis in skeletal muscles is regulated by two main receptors, the ryanodine receptor type I and the dihydropyridine receptor, and by a variety of intracellular second messenger systems. They have a direct or indirect Ca releasing potency from the sarcoplasmic reticulum in common. However, it is not known whether a passive accumulation of Ca might also be a relevant mechanism in MH. Hence, the aim of this study was to examine whether the blockade of the Ca reuptake in the sarcoplasmic reticulum is a potent method to induce in vitro contractures in MH susceptible (MHS) and MH normal (MHN) skeletal muscle specimens. To answer this question in porcine in vitro contracture tests we used cyclopiazonic acid (CPA). We examined the in vitro effects of CPA in a cumulative pattern in MHS and MHN porcine skeletal muscle specimens.

Preoperative Sciatic and Femoral Nerve Blocks for Anterior Cruciate Ligament Reconstruction: A Retrospective Analysis

Objective: Uncontrolled postoperative pain and nausea and vomiting are the most common causes for hospital admission following ambulatory anterior cruciate ligament (ACL) reconstruction. Therefore, finding techniques that provide excellent postoperative pain control is of critical importance. This retrospective study compared patients who received preoperative femoral nerve blockade to those who received combined femoral and sciatic nerve blockade. We hypothesized that a combined preoperative nerve block would result in lower postoperative pain, decreased postoperative opioid consumption, and shorter recovery. Methods: The medical records of 191 patients who underwent ACL reconstruction were retrospectively analyzed. We then developed multivariable regression models for each primary outcome parameter. Results: The postoperative pain scores were lower in patients receiving a combined nerve block compared with patients receiving a femoral nerve block (P<0.001) and higher in patients receiving an autograft vs. an allograft (P=0.009). Total morphine equivalents were lower in patients receiving combined nerve block versus patients receiving femoral nerve block (P<0.001) and higher in patients with a higher BMI (P<0.001). Recovery unit length of stay was prolonged by more than 25 minutes in patients with PONV (P=0.001) and in patients who needed a postoperative nerve block in the recovery unit (P ≤ 0.001). Conclusions: A preoperative combined sciatic and femoral nerve block improved postoperative pain management, while postoperative nausea and vomiting or the need for a postoperative nerve block increased the recovery unit time.