RENAL PROTECTION IN THE CARDIAC SURGERY PATIENT: PERI-OPERATIVE SODIUM BICARBONATE INFUSION (POSBI) OR NOT?

BACKGROUND: Acute renal failure following cardiac surgery is not uncommon and carries a high level of morbidity and mortality. The aim of our study was to determine whether perioperative sodium bicarbonate infusion (POSBI) would decrease acute kidney injury in cardiac surgery patients and improve post-operative outcomes. METHODS: A retrospective analysis of 318 cardiac surgery patients from 2008-2011 was performed. Clinical parameters were compared in patients receiving POSBI versus sodium chloride. Serum creatinine levels were measured in the first five post-operative days. The primary outcome measured was the number of patients developing post-operative renal injury. Secondary outcomes included three-month mortality, intensive care unit and hospital length of stay. RESULTS: Patients given POSBI showed no significant differences compared to the normal saline cohort in regards to increases in serum creatinine [< 25% rise in Cr: 93% vs 94%; > 25% rise in Cr: 6% vs 6%; > 50% rise in Cr: 1% vs 1%; > 100% rise in Cr: 1% vs 0%, all with p-value > 0.99]. There were fewer patients with AKIN stage 1 renal failure receiving POSBI [8% vs 28%, p = 0.02] however there was no difference between POSBI and sodium chloride cohorts in AKIN stages 2 and 3 renal failure. Mortality, duration of hospitalization and ICU stay were not statistically significant. CONCLUSIONS: POSBI resulted in fewer patients developing AKIN stage 1 renal failure. Despite this, there appears to be little benefit in the prevention of acute kidney injury after 48 hours or mortality reduction in cardiac surgery patients.

RESIDENT IMPLEMENTATION OF THE 2007 ACC/AHA GUIDELINES ON PREOPERATIVE CARDIAC EVALUATION IN NON-CARDIAC SURGERY PATIENTS: IS CLINICAL EXPERIENCE ENOUGH?

BACKGROUND: Preoperative evaluation of surgical patients is important, as perioperative complications are associated with increased mortality. Specialties including anesthesiology, internal medicine, cardiology, and surgery are involved in the evaluation and management of these patients. This institutional study investigated the residents' knowledge of the 2007 American College of Cardiology/American Heart Association (ACC/AHA) guidelines on perioperative evaluation of patients undergoing non-cardiac surgery. METHODS: This pilot study used a web-based survey questionnaire to assess resident's knowledge of the 2007 ACC/AHA guidelines through individual steps and corresponding branch point(s) in twelve clinical scenarios. Additionally, residents were asked if they were aware of, or if they had received lectures on ACC/AHA guidelines. Staff anesthesiologists with training in cardiac and intensive care medicine validated the scenarios. RESULTS: A total of 104 resident participants were surveyed including 35 anesthesiology residents, 41 internal medicine residents, 20 surgery residents, and 8 cardiology fellows. Awareness of the 2007 ACC/AHA guidelines by specialty was: anesthesiology (85%), internal medicine (97.6%), cardiology (100%), and surgery (70%). Only 54.3% of anesthesiology, 31.7% of internal medicine, 100% of cardiology, and 10% of surgery residents stated they received lectures. The overall mean score achieved on the eleven scenarios was 50.4% for anesthesiology, 47.0% for internal medicine, 55.7% for cardiology, and 42.3% for surgery. CONCLUSIONS: Although the majority of residents were aware of the 2007 ACC/AHA guidelines, fewer received lectures and regardless of specialty, implementation of these guidelines was poor. There exists significant room for improvement in the understanding of preoperative assessment of non-cardiac surgery patients.

Accidental dural puncture, postdural puncture headache, intrathecal catheters, and epidural blood patch: revisiting the old nemesis.

One of the controversial management options for accidental dural puncture in pregnant patients is the conversion of labor epidural analgesia to continuous spinal analgesia by threading the epidural catheter intrathecally. No clear consensus exists on how to best prevent severe headache from occurring after accidental dural puncture. To investigate whether the intrathecal placement of an epidural catheter following accidental dural puncture impacts the incidence of postdural puncture headache (PDPH) and the subsequent need for an epidural blood patch in parturients. A retrospective chart review of accidental dural puncture was performed at Hutzel Women's Hospital in Detroit, MI, USA for the years 2002-2010. Documented cases of accidental dural punctures (N = 238) were distributed into two groups based on their management: an intrathecal catheter (ITC) group in which the epidural catheter was inserted intrathecally and a non-intrathecal catheter (non-ITC) group that received the epidural catheter inserted at different levels of lumbar interspaces. The incidence of PDPH as well as the necessity for epidural blood patch was analyzed using two-tailed Fisher's exact test. In the non-ITC group, 99 (54 %) parturients developed PDPH in comparison to 20 (37 %) in the ITC [odds ratio (OR), 1.98; 95 % confidence interval (CI), 1.06-3.69; P = 0.03]. Fifty-seven (31 %) of 182 patients in the non-ITC group required an epidural blood patch (EBP) (data for 2 patients of 184 were missing). In contrast, 7 (13 %) of parturients in the ITC group required an EBP. The incidence of EBP was calculated in parturients who actually developed headache to be 57 of 99 (57 %) in the non-ITC group versus 7 of 20 (35 %) in the ITC group (OR, 2.52; 95 % CI, 0.92-6.68; P = 0.07). The insertion of an intrathecal catheter following accidental dural puncture decreases the incidence of PDPH but not the need for epidural blood patch in parturients.

Special article: mandragora: anesthetic of the ancients.

Initial attempts at surgical anesthesia began many centuries ago, with the plants of antiquity. The mandragora, or mandrake, was used as a sedative and to induce pain relief for surgical procedures. It has been depicted in tablets and friezes since the 16th century before the common era (BCE) and used for its sedative effects by Hannibal (second century BCE) against his enemies. The Romans used the mandrake for surgery. The Arabs translated the scientific work of the Ancients and expanded on their knowledge. They developed the Spongia Somnifera, which contained the juice of the mandrake plant. After the fall of the Islamic cities of Europe to the Christians, scientific work was translated into Latin and the Spongia Somnifera was used in Europe until the discovery of the use of ether for surgical anesthesia.

Anesthesia outcome prediction.

This paper studies the problem of outcome prediction in anesthesia procedures. Anesthesia depth and blood pressures are used as typical outcomes in this study. Traditional diagnosis and control in anesthesia focus on a one-drug-one-outcome scenario. It is well understood, however, that consideration of multiple outcomes is necessary and beneficial for anesthesia managements. This paper introduces a method of modeling that significantly reduces the complexity of the problem and yet retains model accuracy. Utility of the modeling method is demonstrated in the areas of anesthesia outcome prediction and decision assistance.

A comparison of a silicone wire-reinforced tube with the Parker and polyvinyl chloride tubes for tracheal intubation through an intubating laryngeal mask airway in patients with normal airways undergoing general anesthesia.

BACKGROUND: The intubating laryngeal mask airway (ILMA) is used in the management of difficult intubation. Usually, a silicone wire-reinforced tube is inserted for tracheal intubation. Because the silicone wire-reinforced tube is expensive, alternatives, such as polyvinyl chloride (PVC) and posterior beveled Parker tubes, are worth considering. We compared the blind intubation success rates among the silicone wire-reinforced tube, the Parker tube, and the PVC tube, and identified laryngeal structures preventing tracheal intubations through the ILMA. METHODS: Sixty-three adult patients were randomized into three groups: Group I (n = 20) silicone wire-reinforced tube, Group II (n = 21) Parker tube, and Group III (n = 22) PVC tube. Demographic and clinical continuous data were compared with the analysis of variance with the Scheffé test for post hoc analysis. Frequencies and percentages were compared with the chi(2) test. RESULTS: Tracheal intubation was successful from the first attempt in 18 of 20 patients in Group I (silicone wire-reinforced tube), which was significantly higher than the success rate in either Group II (12 of 22 patients) (Parker tube) or Group III (10 of 21 patients) (PVC tube). With clockwise or anticlockwise rotation of the tracheal tube, the number of successful intubations did not change in Group I, but it increased to 19 of 22 patients in Group II and to 12 of 21 patients in Group III. The rate of successful intubation between patients in Group I (90%) and Group II (86%) was not significantly different after manipulation of the tracheal tube (P = 0.72). However, the rate of successful tracheal intubations in patients of Group III (57%) was significantly lower in comparison to patients in both Group I (P = 0.02) and Group II (P = 0.03). In 3 of the 22 patients of Group II and in 9 of the 21 patients of Group III in whom blind intubation was not possible, the obstruction was due to the epiglottis tubercule. CONCLUSIONS: Manipulation improved the success rate of intubation with the Parker tube through the ILMA rendering it a possible alternative to the silicone wire-reinforced tube.

Does ondansetron or granisetron prevent subarachnoid morphine-induced pruritus after cesarean delivery?

BACKGROUND: We compared the efficacy of granisetron and ondansetron for the prevention of subarachnoid morphine-induced pruritus after cesarean delivery. METHODS: The incidence of pruritus was assessed in parturients who were randomly allocated into Group G (granisetron 3 mg IV, n = 45), Group O (ondansetron 8 mg IV, n = 42), and Group S (saline IV, n = 42). RESULTS: The incidence of pruritus was not significantly different among the 3 groups (86.6% in Group S, 83.3% in Group O, and 88% in the Group G). CONCLUSION: Neither prophylactic ondansetron nor granisetron reduced the incidence of subarachnoid morphine-induced pruritus when compared with the saline group.

Decision-oriented multi-outcome modeling for anesthesia patients.

Anesthesia drugs have impact on multiple outcomes of an anesthesia patient. Most typical outcomes include anesthesia depth, blood pressures, heart rates, etc. Traditional diagnosis and control in anesthesia focus on a one-drug-one-outcome scenario. This paper studies the problem of real-time modeling for monitoring, diagnosing, and predicting multiple outcomes of anesthesia patients. It is shown that consideration of multiple outcomes is necessary and beneficial for anesthesia managements. Due to limited real-time data, real-time modeling in multi-outcome modeling requires low-complexity model strucrtures. This paper introduces a method of decision-oriented modeling that significantly reduces the complexity of the problem. The method employs simplified and combined model functions in a Wiener structure to contain model complexity. The ideas of drug impact prediction and reachable sets are introduced for utility of the models in diagnosis, outcome prediction, and decision assistance. Clinical data are used to evaluate the effectiveness of the method.