Chong Tan

Plasma-Lyte 148: A clinical review

AIM To outline the physiochemical properties and specific clinical uses of Plasma-Lyte 148 as choice of solution for fluid intervention in critical illness, surgery and perioperative medicine. METHODS We performed an electronic literature search from Medline and PubMed (via Ovid), anesthesia and pharmacology textbooks, and online sources including studies that compared Plasma-Lyte 148 to other crystalloid solutions. The following keywords were used: “surgery”, “anaesthesia”, “anesthesia”, “anesthesiology”, “anaesthesiology”, “fluids”, “fluid therapy”, “crystalloid”, “saline”, “plasma-Lyte”, “plasmalyte”, “hartmann’s”, “ringers” “acetate”, “gluconate”, “malate”, “lactate”. All relevant articles were accessed in full. We summarized the data and reported the data in tables and text. RESULTS We retrieved 104 articles relevant to the choice of Plasma-Lyte 148 for fluid intervention in critical illness, surgery and perioperative medicine. We analyzed the data and reported the results in tables and text. CONCLUSION Plasma-Lyte 148 is an isotonic, buffered intravenous crystalloid solution with a physiochemical composition that closely reflects human plasma. Emerging data supports the use of buffered crystalloid solutions in preference to saline in improving physicochemical outcomes. Further large randomized controlled trials assessing the comparative effectiveness of Plasma-Lyte 148 and other crystalloid solutions in measuring clinically important outcomes such as morbidity and mortality are needed.

Postoperative wristwatch-induced compressive neuropathy of the hand: a case report

IntroductionPostoperative peripheral nerve injuries are well-recognised complications of both surgery and anaesthesia and a leading cause of litigation claims. We present a rare cause of compressive sensory and motor neuropraxia of the median, ulnar and radial nerves of the right hand resulting from a wristwatch that was worn on the first postoperative night following minor surgery. Mechanisms of this compressive neuropathy are discussed, with specific recommendations made regarding the wearing of wristwatches, jewellery and constrictive clothing in the immediate postoperative period.Case presentationA 12-year-old white boy presented with a complete glove and stocking sensory and motor neuropathy involving his right hand from a wristwatch that was worn on the first postoperative night following uneventful surgery for a minor procedure. Over the following 12 hours the oedema and erythema resolved with complete return of motor function. After 18 hours, the sensory deficit completely resolved.ConclusionsPostoperative neuropraxia is often preventable. Paediatric patients, especially if thin, may be particularly susceptible to a compression neuropathy from constrictive clothing or jewellery, in particular circumferential varieties such as wristwatches. These items should not be worn in the immediate postoperative period as pressure on peripheral nerves can result in severe and debilitating nerve injury. Education should be given to all medical staff, carers or parents of children undergoing surgery on the avoidance of wearing wristwatches, jewellery or constrictive clothing in the immediate postoperative period. Early medical evaluation of any postoperative nerve injury is of paramount importance.

Apneic Oxygenation Versus Low-Tidal-Volume Ventilation in Anesthetized Cardiac Surgical Patients: A Prospective, Single-Center, Randomized Controlled Trial

OBJECTIVES To compare the physiology of apneic oxygenation with low-tidal-volume (VT) ventilation during harvesting of the left internal mammary artery. DESIGN Prospective, single-center, randomized trial. SETTING Single-center teaching hospital. PARTICIPANTS The study comprised 24 patients who underwent elective coronary artery bypass grafting surgery. INTERVENTIONS Apneic oxygenation (apneic group: 12 participants) and low-VT ventilation (low-VT group: 12 participants) (2.5 mL/kg ideal body weight) for 15 minutes during harvesting of the left internal mammary artery. MEASUREMENT AND MAIN RESULTS The primary endpoint was an absolute change in partial pressure of arterial carbon dioxide (PaCO2). Secondary endpoints were changes in arterial pH, pulmonary artery pressures (PAP), cardiac index, and pulmonary artery acceleration time and ease of surgical access. The mean (standard deviation) absolute increase in PaCO2 was 31.8 mmHg (7.6) in the apneic group and 17.6 mmHg (8.2) in the low-VT group (baseline-adjusted difference 14.2 mmHg [95% confidence interval 21.0-7.3], p<0.001). The mean (standard deviation) absolute decrease in pH was 0.15 (0.03) in the apneic group and 0.09 (0.03) in the low-VT group baseline-adjusted difference 0.06 [95% confidence interval 0.03-0.09], p<0.001. Differences in the rate of change over time between groups (time-by-treatment interaction) were observed for PaCO2 (p<0.001), pH (p<0.001), systolic PAP (p = 0.002), diastolic PAP (p = 0.023), and mean PAP (p = 0.034). Both techniques provided adequate ease of surgical access; however, apneic oxygenation was preferred predominantly. CONCLUSIONS Apneic oxygenation caused a greater degree of hypercarbia and respiratory acidemia compared with low-VT ventilation. Neither technique had deleterious effects on PAP or cardiac function. Both techniques provided adequate ease of surgical access.