Hon-Ping Lau

Preoperative plasma N‐terminal pro‐brain natriuretic peptide as a marker of cardiac risk in patients undergoing elective non‐cardiac surgery

Plasma N‐terminal pro‐brain natriuretic peptide (NTproBNP) is a sensitive marker for heart failure. This study tested whether the preoperative plasma level of NTproBNP could predict cardiac complications in patients undergoing non‐cardiac surgery.

Successful treatment of advanced bisphosphonate-related osteonecrosis of the mandible with adjunctive teriparatide therapy.

The management of bisphosphonate‐related osteonecrosis of the jaws (BRONJ) is challenging and controversial. At present, there is no established medication treatment for the disease.

A randomised double-blind controlled study evaluating the hypothermic effect of 150 μg morphine during spinal anaesthesia for Caesarean section

We studied the hypothermic effect of adding 150 μg morphine during spinal anaesthesia in 60 parturients scheduled for elective caesarean section. All the parturients received intrathecal injection of a solution containing 150 μg morphine or normal saline in addition to 10–12 mg hyperbaric bupivacaine 0.5%. In both groups, a significant decrease in body temperature was noted. There was no difference in the area under the curve for temperature against time for the two groups; however, the maximum decrease in temperature from baseline was significantly larger after morphine than after saline injection (mean (SD) 1.11 (0.61) °C vs 0.76 (0.39) °C, respectively; p = 0.01) and the time to nadir temperature was significantly longer (59.5 (17.6) min vs 50.4 (15.9) min, respectively; p = 0.047). The lowest temperature observed in the morphine group was 34.3 °C. We conclude that intrathecal injection of 150 μg morphine intensified the intra‐operative hypothermic effect of bupivacaine spinal anaesthesia for caesarean section.

Iatrogenic Left Internal Iliac Artery Perforation During Lumbar Discectomy

Iatrogenic intra-abdominal vascular injury can result from lumbar discectomy via the posterior approach. Although it is well known and documented in the literature, few anesthesiologists have personal experience with this life-threatening incident. Here, we report a patient who sustained perforation of the left internal iliac artery at the L(4-5) level during posterior lumbar discectomy. The patient experienced refractory hypotension with tachycardia at the end of surgery, even with prompt fluid resuscitation and medical treatment. Abdominal distension and tenderness of the left lower abdominal quadrant were also noted. Emergency laparotomy was performed by the consulting vascular surgeon and revealed perforation of the left internal iliac artery. The vascular injury was successfully repaired. It is important that, as anesthesiologists, we must be aware of this potentially fatal complication. Prompt diagnosis and immediate laparotomy to control hemorrhage can result in favorable outcomes.

Delayed Airway Obstruction Secondary to Inadvertent Arterial Puncture during Percutaneous Central Venous Cannulation

We report a case of fatal respiratory complication secondary to central venous cannulation in a 63-year-old male patient, which came up gradually and insidiously following an accidental puncture of carotid artery in an attempt to cannulate the right internal jugular vein. He died 14 h after the mishap due to severe upper airway obstruction. The nature of the vascular laceration was still obscure.

Sex Differences in Conscious Sedation During Upper Gastrointestinal Panendoscopic Examination

BACKGROUND/PURPOSE Sex differences in response to noxious stimuli or analgesia have been demonstrated. We investigated sex differences in conscious sedation during upper gastrointestinal panendoscopic examination with regard to drug dose and entropy scores. METHODS We investigated sex differences in 30 men and 30 women who were undergoing conscious sedation during upper gastrointestinal panendoscopic examination. The drug mixture was prepared as 5 mg midazolam plus 1 mg alfentanil diluted with normal saline to a volume of 10 mL. An initial injection of 4 mL was followed by an additional 1 mL every 1 minute, until the modified Observer Assessment of Alertness and Sedation (OAAS) rating scale was ≤ 3 when the panendoscope was inserted. Further injection was allowed thereafter. Entropy values, including state entropy (SE) and response entropy (RE), were monitored from baseline to full recovery. RESULTS The volume of mixture needed to achieve an OAAS score of ≤ 3 was significantly lower in men than in women (4.4 ± 0.7 mL vs. 4.8 ± 0.8 mL, p = 0.034). The initial drug demand was not significantly influenced by age, body weight, or body height. The RE and SE values at the time of panendoscope insertion were not significantly different between men and women. The total volume for men was also significantly lower than that for women (5.7 ± 1.1 mL vs. 6.5 ± 1.4 mL, p < 0.01). The lowest RE and SE values during the procedure were not significantly different between men and women. CONCLUSION Women need more analgesic agents than men during panendoscopic examination. There was no significant difference between men and women with regard to anesthetic depth and response to noxious stimuli, as revealed by similar SE and RE values.

Anesthetic management for two infants undergoing surgery for tension pneumatoceles

SIR—A pneumatocele is a thin-walled air-filled cyst of the lung. It often occurs in children as a sequel of bacterial pneumonia but can also occur after blunt thoracic trauma, positive pressure ventilation and caustic aspiration. Although most pneumatoceles regress with resolution of the underlying disease, tension pneumatoceles may occasionally occur and cause cardiopulmonary instability and surgical intervention should be considered (1). Reports in the literature of anesthesia management in infants with pneumatoceles are rare. We report our experience in two infants with tension pneumatoceles. The first patient was a previously healthy 10-month-old male infant who developed pneumatoceles after resolution of pneumonia. The chest X-ray showed complete resolution of the pneumonia, although many small pneumatoceles were noted at the lower field of the left lung (Figure 1a). The patient had sudden onset of tachypnea 1 month later. Chest X-ray showed multiple, variably sized, air-filled cystic lesions occupying the left hemithorax. The heart was pushed toward the right side (Figure 1b). Computed tomography (CT) scan of the chest showed multiple pneumatoceles occupying the left pleural cavity with the largest >10 cm in diameter. The mediastinum was deviated to the right side, and the remaining left lung was severely compressed (Figure 1c). After placement of a chest tube, follow-up chest X-rays did not show complete normalization of the mediastinum (Figure 1d). The baby was taken to the operating room for definitive resection of the pneumatoceles. Before anesthesia, intra-arterial pressure and pulse oximetry were monitored. After 5 min preoxygenation, ketamine was used for induction to keep spontaneous respiration. Decreased oxygen saturation down to 80% was noted during intubation attempts. Laryngospasm developed and SpO2 became worse. Succinylcholine was given for relief of spasm and positive pressure mask ventilation was used. After tracheal tube intubation, oxygen saturation as low as 60% was noted with decrease of blood pressure (BP) and heart rate (HR) 1 . He was resuscitated with percutaneous needle decompression using three 14G venous catheters in the second intercostal space, anterior and posterior axillary lines at the fifth rib, respectively. The vital signs resumed stable after needle decompression. Through a left-sided thoracotomy, lobectomy of the left lower lung lobe was performed. The postoperative course was uneventful and he was discharged 7 days later. The second patient was a 12-day-old infant experiencing intermittent tachypnea and subcostal retraction. Chest X-ray revealed left upper lobe collapse and multiple airfilled cystic lesions over left lower lobe. The heart was pushed toward the right side (Figure 2a). CT scan of the chest showed multiple pneumatoceles occupying the left lower lobe, the mediastinum was deviated to the right side and the remaining left lung was severely compressed (Figure 2b). The baby was taken to the operating room emergently for definitive resection of multiple tension pneumatoceles. Before anesthesia, intra-arterial pressure and pulse oximetry were monitored. Anesthesia was induced with ketamine after 5 min preoxygenation. We paralyzed the patient with muscle relaxant and applied low positive pressure mask ventilation (not higher than 10 cmH2O). The tracheal tube was inserted smoothly with intentional deviation to the right side. One-lung ventilation was conformed by auscultation and by fiberoptic bronchoscopy. Oxygen saturation was kept above 95% without desaturation during the induction and hemodynamics were stable throughout with monitoring of BP, CVP, SpO2, electrocardiogram and temperature. Fentanyl and midazolam were used intraoperatively. Through a left-sided open thoracotomy, multiple cystic lesions were noted at left lower lobe and left lower 2 Figure 1 Chest images of infant 1. Pediatric Anesthesia 2007 17: 189–198